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1.
To investigate the mechanism of cystic cavity formation in the cerebral white matter of the HTX rat, a strain with inherited hydrocephalus, the authors carried out a histopathological study of the brain in pups from birth to postnatal day (P) 26. Cystic cavities were formed in the cerebral white matter on the lateral side of the basal ganglia of all HTX rats with moderate to severe ventricular dilatation and, additionally, in the white matter beneath the paramedian cortex in advanced cases at P10-26. In the initial stage of cyst formation, disarrangement of the ependymal cell layer and spongy alteration of the white matter took place in pups between P1 and P7. The ependymal disarrangement involved disruption and flattening of the ependymal cells, which were often devoid of microvilli, cilia and intercellular junctional complexes. The spongy state was due to expansion of the extracellular space and multiple microcyst formation with fluid accumulation in the early stage, and large cystic cavities in the advanced stage. The cerebrospinal fluid (CSF) in the ventricle communicated with the fluid in the cystic cavities via the disarranged ependymal cell layer. The ependymal damage was more prominent at the lateral wall of the posterior horn than at the anterior horn of the lateral ventricles. These cavities were demarcated by reactive glial cells in the advanced stage. However, the cavities enlarged in accordance with progressive dilatation of the lateral ventricles during postnatal development.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
2.
Paraoxonase 1 gene polymorphisms in patients with osteonecrosis of the femoral head with and without cerebral white matter lesions. 总被引:2,自引:0,他引:2
Georgios M Hadjigeorgiou Konstantinos Malizos Efthimios Dardiotis Konstantinos Aggelakis Maria Dardioti Aristidis Zibis Apostolos Dimitroulias Nikolaos Scarmeas Aspasia Tsezou Apostolos Karantanas 《Journal of orthopaedic research》2007,25(8):1087-1093
Cerebral white matter lesions (WML) are present in more than 50% of patients with osteonecrosis of the femoral head (ONFH). Paraoxonase 1 (PON1) gene product is a detoxifying and pesticide metabolizing enzyme. Genetic variants of the PON1 gene have been found to influence the occurrence and progression of WML. We examined whether two PON1 polymorphisms (M55L and R192Q) are associated with ONFH and influence the occurrence of WML. We studied 104 patients with ONFH and 113 healthy age- and sex-matched subjects. We used logistic regression models to examine associations and survival analyses (Cox proportional hazards models) to examine possible influence of alleles on age at onset of ONFH. We found no association of PON1 M55L alleles and genotypes with ONFH. The distribution of PON1 Q192R alleles (p = 0.001) and genotypes (QQ vs. QR/RR) (p = 0.004) were statistically different between controls and patients. Patients with QQ genotype had six times higher risk for WML at brain MRI (adjusted OR 5.95; 95% CI 1.30-27.03; p = 0.02). In Cox models, there was a significant association of allele Q with risk for ONFH indicating a possible dose effect (HR = 1.43; 95%CI = 1.04-1.97; p for trend = 0.03). We conclude that individuals with PON1 192QQ genotype may have increased risk for ONFH and WMLeOn. 相似文献
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Roberto Rivas Frederic Shapiro 《The Journal of bone and joint surgery. American volume》2002,(1):85-100
BACKGROUND: Histologic delineation of the events involved in the development of long bones and the developmental age at which these events occur is needed to elucidate the genetic and molecular mechanisms associated with these events. This report describes the sequence of histologic events involved in the formation of long bones and their epiphyses in the New Zealand White rabbit. METHODS: Prenatal studies were performed on twelve, fourteen, fifteen, sixteen, eighteen, twenty-one, twenty-four, and twenty-seven-day-old rabbit embryos, and postnatal studies were performed on newborn rabbits and on three-to-four-day-old; one, two, four, and six-week-old; and two, three, four, six, and eight-month-old rabbits. Histologic specimens from embryos were embedded in plastic and stained with toluidine blue or safranin O-fast green, and specimens from postnatal rabbits were embedded in paraffin and stained with hematoxylin and eosin or safranin O-fast green. RESULTS: Studies of twelve-day-old embryos demonstrated upper and lower limb buds filled with undifferentiated mesenchymal cells, and studies of fourteen-day-old embryos showed mesenchymal condensation and beginning cartilage formation outlining major long bones. Long-bone and epiphyseal development progressed through sixteen structural stages, and the developmental age at which these stages occurred was determined. These stages included limb-bud formation with uniform distribution of mesenchymal cells and formation of an apical ectodermal ridge (stage 1); mesenchymal condensation (stage 2); cartilage differentiation (stage 3); formation of a primary center of ossification (stage 4a); epiphyseal cartilage vascularization with formation of cartilage canals (stage 7); vascular invasion of the developing secondary ossification center (stage 9); bone formation and marrow cavitation in the secondary ossification center with formation of hematopoietic marrow (stage 10); fullest relative extent of secondary-ossification-center development in epiphyseal cartilage (stage 14); thinning of the physis (stage 15); and resorption of the physis with establishment of continuity between epiphyseal and metaphyseal circulations (stage 16). 相似文献
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The curvature of the lower lumbar facet joints in the transverse plane was measured using an innovative computed tomographic approach, and its relationship with the orientation of the joints was evaluated. Two hundred three vertebral levels were examined in 116 patients with low back pain. Reference circles were used to quantify joint curvature. The mean curvature (+/- SD) at the levels L3-L4, L4-L5, and L5-S1 conformed to circles of 27.3 mm +/- 11.5; 35.1 mm +/- 14.6; and 51.0 mm +/- 34.5 in diameter respectively. The ratio between the curvature of the facets and their orientation was 62.6% +/- 19.0; 57.8% +/- 21.6; and 64.9% +/- 48.9. From L3-L4 down to L5-S1 the curvature of the facet joints decreases. The differences between L3-L4 and L4-L5 is smaller than between L4-L5 and L5-S1. The curvatures of the joints conform to circles that are in mean approximately 40% in diameter smaller than those to which their orientations conform. 相似文献
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BACKGROUND CONTEXT: A substantial cause of neurological disability in spinal cord injury is oligodendrocyte death leading to demyelination and axonal degeneration. Rescuing oligodendrocytes and preserving myelin is expected to result in significant improvement in functional outcome after spinal cord injury. Although previous investigators have used cellular transplantation of xenografted pluripotent embryonic stem cells and observed improved functional outcome, these transplants have required steroid administration and only a minority of these cells develop into oligodendrocytes. PURPOSE: The objective of the present study was to determine whether allografts of oligodendrocyte precursors transplanted into an area of incomplete spinal cord contusion would improve behavioral and electrophysiological measures of spinal cord function. Additional treatment incorporated the use of the glycoprotein molecule Sonic hedgehog (Shh), which has been shown to play a critical role in oligodendroglial development and induce proliferation of endogenous neural precursors after spinal cord injury. SETTING: Laboratory study. METHODS: Moderate spinal cord contusion injury was produced in 39 adult rats at T9-T10. Ten animals died during the course of the study. Nine rats served as contusion controls (Group 1). Six rats were treated with oligodendrocyte precursor transplantation 5 days after injury (Group 2). The transplanted cells were isolated from newborn rat pups using immunopanning techniques. Another eight rats received an injection of recombinant Shh along with the oligodendrocyte precursors (Group 3), while six more rats were treated with Shh alone (Group 4). Eight additional rats received only T9 laminectomies to serve as noninjured controls (Group 0). Animals were followed for 28 days. RESULTS: After an initial complete hindlimb paralysis, rats of all groups receiving a contusive injury recovered substantial function within 1 week. By 28 days, rats in Groups 2 and 3 scored 4.7 and 5.8 points better on the Basso, Beattie, Bresnahan (BBB) open field locomotor score than rats in group 1 (Groups 2 and 3=18.2 and 19.4 points, respectively, after 28 days vs. Group 1=13.6 points; p=.015). Rats in Group 4 scored no better than those in Group 1 (BBB=16.4). Motor evoked potential (MEP) recordings revealed a strong trend towards significant improvement in latency measurements in all treatment groups compared with controls at 28 days, although three animals in Group 1 and two animals in Group 3 were not recordable. Histological examination demonstrated significantly more spared white matter in the same groups that correlated with the improvements in BBB scores and MEP latencies. Immunohistochemical analysis showed the survival, proliferation and migration of the transplanted cells, as well as the induction of proliferating endogenous neural precursor cells in animals treated with Shh.CONCLUSIONS: These findings suggest that the transplantation of oligodendrocyte precursors may improve axonal conduction and spinal cord function in the injured spinal cord. The benefits seem more pronounced with the addition of Shh, and the addition of Shh alone results in the proliferation of an endogenous population of neural precursor cells. 相似文献
7.
Biochemical markers of bone turnover and the volume and the density of bone in children at different stages of sexual development. 总被引:3,自引:0,他引:3
S Mora P Pitukcheewanont F R Kaufman J C Nelson V Gilsanz 《Journal of bone and mineral research》1999,14(10):1664-1671
Bone mass and biochemical markers of bone turnover increase significantly during puberty. We studied the possible relationships between markers of bone formation and bone resorption and increases in skeletal size, bone volume, and bone density in healthy children at different stages of sexual development. Serum concentrations of bone specific alkaline phosphatase (BALP) and osteocalcin (bone Gla protein, BGP), urinary levels of pyridinoline (Pyr) and deoxypyridinoline (Dpyr) and computed tomography (CT) measurements of the cross-sectional areas of the vertebrae and the femurs, the apparent density of cancellous bone in the vertebrae, and the volume and the material density of cortical bone in the femurs were determined in 126 boys and 143 girls, ages 7-18 years. Serum levels of BALP and BGP and urinary concentrations of Pyr and Dpyr peaked in early puberty and were lowest in the later stages of puberty. CT measurements for the cross-sectional areas of the vertebrae and the femurs, the femoral cortical bone areas, and the apparent density of cancellous bone increased in all children during puberty, while values for material bone density did not change significantly with the stage of sexual development. BALP and BGP showed significant inverse correlations with the material density of bone (r = -0.23 and -0.24, respectively), but no association with bone volume in the appendicular or axial skeleton. In contrast, Pyr and Dpyr correlated with femoral cross-sectional area (r = -0.24 and -0.33, respectively) and cortical bone area (r = -0.29 and -0.33, respectively), and with the apparent density of vertebral cancellous bone (r = -0.26 and -0.19, respectively), but not with the material density of bone. We conclude that, during puberty, there is a differential association between the two components of bone mass and the markers of bone formation and bone resorption; while markers of bone formation are related to the material density of bone, markers of bone resorption are related to the volume of bone. 相似文献
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【摘要】 目的:探讨青少年特发性脊柱侧凸(AIS)患者主胸弯融合后未融合上胸弯的变化及其与肩部平衡的关系。方法:回顾性分析2008年1月~2010年12月在我院接受手术治疗的AIS患者,选取年龄10~18岁,Lenke分型为Lenke 1、2、3、4型,右胸弯且Cobb角<80°,采用后路椎弓根螺钉系统固定矫形,固定融合上端椎在T4或T4以下,随访时间2年以上的患者,排除翻修手术和截骨手术患者。术前根据Lenke分型判断上胸弯是否为结构性,分成结构性上胸弯组和非结构性上胸弯组,统计比较两组术前、术后3个月和末次随访时外观肩部平衡以及影像学各项参数的变化。结果:共有62例患者纳入本研究,平均年龄14.4岁,随访时间24~62个月,平均36.4个月,其中结构性上胸弯组17例,非结构性上胸弯组45例。两组患者术后上胸弯均能自发性矫正,末次随访时,上胸弯Cobb角平均由27.9°减小至19.4°,T1倾斜角由-0.21°增加至4.7°,第一肋倾斜角(FRT)由0.4°增加至3.7°,锁骨角(CA)由-1.5°增加至0.8°,双肩高度差(CSH)由-13.0mm增加至5.2mm,改变均有统计学意义(P=0.000)。Pearson相关性分析显示,T1倾斜角的改变(术后T1倾斜角-术前T1倾斜角)与CSH变化(术后CSH-术前CSH)有较强相关性(r=0.624,P=0.000),术后主胸弯的矫正率和FRT与CSH变化为中等程度相关(r=0.437,0.345,P=0.007,0.006),术前主胸弯Cobb角与CSH变化为弱相关(r=0.262,P=0.040)。上胸弯Cobb角及柔韧性、主胸弯柔韧性、T1倾斜角等参数与CSH变化无统计学相关性。结论:AIS患者结构性与非结构性上胸弯在主胸弯矫正以后均有自发性矫正现象,但T1倾斜角、第一肋倾斜角和双肩高度差均会增加。右胸弯患者左肩被抬高的程度与T1倾斜角增加的程度、主胸弯的矫正率及术后第一肋倾斜角相关。 相似文献
10.
袁平龙艳君杨霞袁静程世平查艳 《中国骨质疏松杂志》2014,(1)
目的研究不同分期慢性肾脏病患者血清胰岛素样生长因子-1(IGF-1)的表达与骨密度(BMD)的相关性。方法选取CKD2~5期患者各25例,应用DEXA骨密度仪测定1-4腰椎前后位BMD和T值,检测血清IGF-1水平及其他相关生化指标的表达。结果 CKD5期患者BMD和T值与体检人群有明显差异(P0.05),血清IGF-1值显著减少(P0.01),血清甲状旁腺激素(iPTH)及碱性磷酸酶(ALP)明显增高(P0.01),且血清IGF-1水平与BMD呈正相关(r=0.673)。结论 BMD测定敏感性较高,是目前早期诊断肾性骨病的较好方法;血清IGF-1值不仅可反应骨转换水平高低,而且与慢性肾脏病5期患者BMD的变化相平行,对CKD患者肾性骨病早期诊治和严重程度的判断中亦具有重要临床价值。 相似文献
11.
K Moritake H Handa Y Yonekawa W Taki T Okuno 《No shinkei geka. Neurological surgery》1986,14(8):957-963
Follow-up studies over more than one and a half years (average 6.5 years) were performed in 51 patients with "moyamoya disease". Activities of daily living (ADL) was assessed and graded into five levels both at the time of admission into hospital and at the last assessment in the follow-up study, as follows. Grade I: Fully capable of work or study with no or minimal difficulty, II: Capable of limited work or study with difficulty, III: Incapable of work or study but capable of home life alone, IV: Incapable of home life without help, V: Vegetative state or dead. Patients were divided into three groups by the age of clinical onset: younger pediatric, less than 5 years old (21 patients); older pediatric, 5 to 15 years old (14 patients); and adult, 16 years old and over (16 patients). Although analysis of the angiographical and neurological pictures is important, the present paper concerns only the age of clinical onset and whether reconstructive vascular surgery was performed, because of the small number of clinical materials. Seven of 16 adults suffered hemorrhagic attacks and 2 of them died of hemorrhagic insults. In contrast, none of the pediatric cases had hemorrhagic attacks and none died. Both at the time of admission and last assessment, ADL of younger pediatric cases was much lower than that of older ones. These results suggest that clinical course in patients with "moyamoya disease" closely related with the age of the onset of illness, and the border age of onset of illness between patients with good outcome and with poor outcome is around 5 years.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
12.
K E Gregory D R Keene S F Tufa G P Lunstrum N P Morris 《Journal of bone and mineral research》2001,16(11):2005-2016
Collagen type XII is a member of the fibril-associated collagens and is characterized by a short triple-helical domain with three extended noncollagenous NC3 domains. Previous studies suggested that collagen XII is a component of cartilage but little is known about its spatial-temporal distribution. This study uses a polyclonal antibody to the purified NC3 domain to investigate its developmental distribution in rat forelimb. Collagen XII was present at the joint interzone on embryonic day 16 (E16d) and restricted to the presumptive articular cartilage by E18d. Labeling of the articular surface intensified as development progressed postnatally (day 1 [1d] to 28d) and extended approximately six cell diameters deep. In juvenile rats, collagen XII antibodies also labeled the longitudinal and transverse septa of stacked chondrocytes in the growth plate. However, collagen XII was not associated at any developmental stage with the cartilaginous secondary ossification center and was only weakly expressed in epiphyseal cartilage. Ultrastructural localization of the NC3 domain epitope showed labeling of the surface of collagen II fibrils both in tissue and in isolated fibrils. The results presented provide further evidence that articular cartilage differs substantially from the underlying epiphyseal cartilage and that different chondrocytic developmental fates are reflected in the composition of their extracellular matrix starting early in development. In addition, collagen XII was distributed in areas of cartilage with more organized fibril orientation and may have a role in promoting alignment or stabilizing such an organization, thereby creating a matrix capable of withstanding load-bearing forces. 相似文献
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R H Gelberman M I Boyer M D Brodt S C Winters M J Silva 《The Journal of bone and joint surgery. American volume》1999,81(7):975-982
BACKGROUND: Elongation (gap formation) at the repair site has been associated with the formation of adhesions and a poor functional outcome after repair of flexor tendons. Our objectives were to evaluate the prevalence of gap formation in a clinically relevant canine model and to assess the effect of gap size on the range of motion of the digits and the mechanical properties of the tendons. METHODS: We performed operative repairs after sharp transection of sixty-four flexor tendons in thirty-two adult dogs. Rehabilitation with passive motion was performed daily until the dogs were killed at ten, twenty-one, or forty-two days postoperatively. Eight tendons ruptured in vivo. In the fifty-six intact specimens, the change in the angles of the proximal and distal interphalangeal joints and the linear excursion of the flexor tendon were measured as a 1.5-newton force was applied to the tendon. The gap at the repair site was then measured, and the isolated tendons were tested to failure in tension. RESULTS: Twenty-nine tendons had a gap of less than one millimeter, twelve had a gap of one to three millimeters, and fifteen had a gap of more than three millimeters. Neither the time after the repair nor the size of the gap was found to have a significant effect on motion parameters (p > 0.05); however, the ultimate force, repair-site rigidity, and repair-site strain at twenty newtons were significantly affected by these parameters (p < 0.05). Testing of the tendons with a gap of three millimeters or less revealed that, compared with the ten-day specimens, the forty-two-day specimens failed at a significantly (90 percent) higher force (p < 0.01) and had a significantly (320 percent) increased rigidity (p < 0.01) and a significantly (60 percent) decreased strain at twenty newtons (p < 0.05). In contrast, the tensile properties of the tendons that had a gap of more than three millimeters did not change significantly with time. CONCLUSIONS: Our data indicate that, in a dog model involving sharp transection followed by repair, a gap at the repair site of more than three millimeters does not increase the prevalence of adhesions or impair the range of motion but does prevent the accrual of strength and stiffness that normally occurs with time. 相似文献
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We report an uncommon case of heterotopic ossification affecting the median nerve at the level of the distal forearm and carpal tunnel with some unusual features: its length, the concomitant involvement of the ulnar nerve at Guyon's canal and a positive family history of heterotopic ossification. 相似文献
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B Heublein A Auricchio I Wagenbreth A Haverich H A Dieterich 《The Journal of cardiovascular surgery》1992,33(1):21-27
Denervation of the heart involves an alteration (density, distribution of beta 1-beta 2-types) of beta-adrenoceptors in long-term follow-up. To elucidate the influence of these changes on left ventricular contractility and to provide an effective alternative treatment to re-transplantation in cases of chronic rejection (coronary vasculopathy-CVP, unspecific myocardial allograft failure-UMAF) a clinical study on 19 male transplant recipients after orthotopic heart transplantation without CVP and UMAF in the non-rejecting state was undertaken. Six male patients served as a control group to compare the systolic function at rest. Left ventricular end-systolic pressure-volume relationships (ESPVR) (k-slope) were registered and computer measured using a conductance catheter-technique under conditions of a transiently occluded vena cava and at a fixed heart rate (atrial pacing) in all patients (n = 25). In the transplanted patient group the acute response of enoximone (0.75 mg/kg) administered intravenously was recorded. The position of the ESPVR in the transplanted hearts were not different as compared to the data obtained from the non-transplanted hearts at rest. The k-slope increased from the baseline data after the acute infusion of enoximone in the transplanted hearts. The dosage of enoximone used produced a significant leftward shift in the ESPVR in most patients (89%). In addition, 42% of the patients showed an insignificant drop in left ventricular systolic pressure. Thus, the baseline contractile characteristics of the heart transplant recipients without chronic rejection and in the non-rejecting state is not obviously different from those in non-transplanted patients at rest independent of the time since operation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
Vladimir Ivanovich Onopriev Vladimir Moiseevich Durleshter Vadim Valerevich Ryabchun 《European journal of cardio-thoracic surgery》2005,28(1):1-6
OBJECTIVE: The aim of this study was to evaluate main results of morpho-functional state of the esophagus assessment in patients with various stages of achalasia before and after surgical treatment. METHODS: Between 1993 and 2002, a total of 65 patients with achalasia (26 males, 39 females; mean age 44.5+/-14.0 years; range 16-79) underwent specific type of surgical treatment based on the results of functional state of the esophagus assessment. Barium swallow, manometry and 24-h pH-metry were performed by standard methods; the main parameters of each study were evaluated before and after operation. Patients were divided into three groups according to the esophageal diameter (barium swallow examination data). Group I (n = 22, diameter < 4 cm), group II (n = 35, diameter from 4 to 7 cm), group III (n = 8, diameter > 7 cm, with the cardiac stenosis and S-shape deformation of the distal esophagus). All the patients in groups I and II underwent esophagocardiomyotomy with the creation of dilating antireflux cardia by Onopriev (fundoplication + esophageal ligament apparatus reconstruction). Five patients in group III with the cardiac stenosis underwent resection of the cardia with segmental esophagocardioplasty, three patients with the cardiac stenosis and sigmoid esophagus underwent resection of the stenosed cardia, extirpation of the esophageal muco-submucosal layer with subsequent replacement of it with the left colon placed in saved muscular sheath of the esophagus. RESULTS: There were no deaths or reoperations. The study showed that a decrease of both maximal and residual LES pressures after operation in group I (from 24.3+/-3.8 to 21.7+/-2.4 and from 17.2+/-2.4 to 11.8+/-1.4, respectively) and group II (from 29.6+/-2.6 to 21.7+/-2.4 and from 21.7+/-3.1 to 11.8+/-1.4, respectively) of patients with achalasia enables to eliminate obstruction and therefore to decrease esophageal diameter. CONCLUSIONS: We suggest that dilating antireflux cardia provides adequate bolus passage and properly realizes antireflux barrier function, maintaining the esophageal distal pH within the physiological ranges even without esophageal peristalsis restoration, and dilating mechanism serve to prevent the recurrence of the disease. Despite excellent relief of dysphagia and functional state of the esophagus improvement, the main values of functional state assessment results in group III of patients were beyond physiological ranges. 相似文献
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Decreased collagen organization and content are associated with reduced strength of demineralized and intact bone in the SAMP6 mouse. 总被引:1,自引:0,他引:1
Matthew J Silva Michael D Brodt Brigitte Wopenka Stavros Thomopoulos Derek Williams Maurice H M Wassen Mike Ko Nozomu Kusano Ruud A Bank 《Journal of bone and mineral research》2006,21(1):78-88
To examine the link between bone material properties and skeletal fragility, we analyzed the mechanical, histological, biochemical, and spectroscopic properties of bones from a murine model of skeletal fragility (SAMP6). Intact bones from SAMP6 mice are weak and brittle compared with SAMR1 controls, a defect attributed to reduced strength of the bone matrix. The matrix weakness is attributed primarily to poorer organization of collagen fibers and reduced collagen content. INTRODUCTION: The contribution of age-related changes in tissue material properties to skeletal fragility is poorly understood. We previously reported that bones from SAMP6 mice are weak and brittle versus age-matched controls. Our present objectives were to use the SAMP6 mouse to assess bone material properties in a model of skeletal fragility and to relate defects in the mechanical properties of bone to the properties of demineralized bone and to the structure and organization of collagen and mineral. MATERIALS AND METHODS: Femora from 4- and 12-month-old SAMR1 (control) and SAMP6 mice were analyzed using bending and torsional mechanical testing of intact bones, tensile testing of demineralized bone, quantitative histology (including collagen fiber orientation), collagen cross-links biochemistry, and Raman spectroscopic analysis of mineral and collagen. RESULTS: Intact bones from SAMP6 mice have normal elastic properties but inferior failure properties, with 60% lower fracture energy versus SAMR1 controls. The strength defect in SAMP6 bones was associated with a 23% reduction in demineralized bone strength, which in turn was associated with poorer collagen fiber organization, lower collagen content, and higher hydroxylysine levels. However, SAMP6 have normal levels of collagen cross-links and normal apatite mineral structure. CONCLUSIONS: Bones from SAMP6 osteoporotic mice are weak and brittle because of a defect in the strength of the bone matrix. This defect is attributed primarily to poorer organization of collagen fibers and reduced collagen content. These findings highlight the role of the collagen component of the bone matrix in influencing skeletal fragility. 相似文献
18.
Y Kato C Mihara J Matsuyama S Ochi H Ono S Yamaguchi R Kagawa N Sanno N Yanagawa 《Minimally invasive neurosurgery》2004,47(2):65-71
We have analyzed the historical background of women's progress in medicine in Japan and the role of female neurosurgeons as models for the next generation. Female neurosurgeons were asked to complete a questionnaire regarding their professional life in detail and the problems they are facing while managing their personal life after getting married and having a child. Some feel that there remain some constraints at work for being a female, due to their male colleagues who are not so understanding in nature.The younger generation is not so keen on joining the neurosurgical branch as their life career due to hard work and complete dedication demanded by neurosurgery. It is not easy for all to manage a neurosurgical career along together with a married life and children. Hence it is now time for those successful female neurosurgeons to become role models. Government can play an important role in these social reforms by coming up with programs to give social security to females and initiate programs for child care for married females pursuing such a demanding profession. Certain measures to encourage females to take up surgery are providing more time by arranging care for babies and families, flexibility in working hours, in addition to having a considerate husband and a considerate chief of department and senior staff. Departmental policies need to be completely impartial and should promote everyone based on their skills and knowledge. Women neurosurgeons need to get together and discuss all these issues so that the younger generation will not hesitate to take up this profession and become stalwarts of neurosurgery like their male counterparts. 相似文献
19.
Anette Lohmander Christina Persson Py Owman-Moll 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2002,36(6):332-339
The purpose of the study was to investigate the relationship between the size of oronasal openings in the hard palate and speech deficits. Audiotape recordings and plaster casts were taken according to standard procedures at 5 and 7 years of age from 22 consecutive children born with complete unilateral cleft lip and palate treated at Sahlgrenska University Hospital, G?teborg, Sweden. The soft palate had been repaired before the age of 12 months, whereas the cleft in the hard palate was left unrepaired, to be closed later. Perceptual judgements of nine speech variables at 5 and 7 years of age were correlated with measures of the area of the residual cleft in the hard palate. "Retracted oral articulation" (to velar place) found in nine of the 22 children correlated significantly with the area of the cleft at the age of 5 years but not later. The establishment of this particular speech error seems to be related to the size of an oronasal opening. 相似文献
20.
The anti-emetic efficacy of prophylactic ondansetron and tropisetron in combination with a low dose of droperidol in patients with high probability for post-operative nausea and vomiting undergoing gynaecological laparoscopy was compared. Patients were randomly allocated in a double-blind manner to receive either ondansetron 8 mg (n = 45) or tropisetron 5 mg (n = 43) at the end of surgery. A standardized general anaesthetic technique was used, including droperidol 0.75 mg. The incidence of nausea was 36% and 49% (P = 0.28), and vomiting occurred in 13% and 14% of the patients in the ondansetron and tropisetron groups, respectively. The onset time for rescue medication was significantly sooner after tropisetron than ondansetron (3 h 18 min vs. 6 h 25 min; P = 0.007). There were no statistically significant differences in efficacy between prophylactic ondansetron and tropisetron combined with droperidol in a high-risk population. However, ondansetron appeared to be more effective in preventing post-operative nausea and vomiting in the early hours after surgery compared with tropisetron. 相似文献