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71.
Manuel Sosa P. Saavedra J. del Pino-Montes J. Alegre R. Pérez-Cano G. Martínez Díaz Guerra M. Díaz-Curiel C. Valero M. Muñoz-Torres A. Torrijos J. Mosquera C. Gómez-Alonso GIUMO Study Group 《Journal of clinical densitometry》2005,8(4):430-435
Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density (BMD) to evaluate the probability of Colles' fracture. Two-hundred eighty-nine postmenopausal women (62.3 +/- 8.7 yr) with (n = 76) and without (n = 213) Colles' fracture were studied. BMD of lumbar spine and proximal femur was evaluated in all women by dual-energy X-ray absorptiometry (DXA) and speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness in the calcaneus were measured by a Sahara ultrasonometer (Hologic). Patients suffering from Colles' fracture had lower values of BMD adjusted by height at the lumbar spine, L2-L4 (0.797 g/cm2 vs 0.860 g/cm2), femoral neck (0.685 g/cm2 vs 0.712 g/cm2 ), SOS (1518 m/sg vs 1525 m/sg), and stiffness (74.6 vs 77.7) (p < 0.05). Nevertheless, BUA values were similar in both groups. After stepwise logistic regression analysis, the area found under receiver operating characteristic (ROC) curves was 0.60 for L2L4 and 0.63 for a formula combining L2L4 and height. Our data suggest that patients suffering from Colles' fracture have lower values of BMD by DXA, SOS, and stiffness. However, the ability of these techniques to discriminate is low because the values for the area under ROC curve are 0.60 for L2-L4 and 0.63 for a formula derived of the combination of L2-L4 and height. 相似文献
72.
Holger F. Boehm Felix Eckstein Caecilia Wunderer Volker Kuhn Eva-Maria Lochmueller Karin Schreiber Dirk Mueller Ernst J. Rummeny Thomas M. Link 《Journal of clinical densitometry》2005,8(4):488-494
We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL. 相似文献
73.
目的探讨小剂量阿司匹林与银可络联用对老年患者血液流变学异常的影响。方法57例老年病人并伴有高凝、高粘血症者采用小剂量阿司匹林50mg,口服,1次/d,银可络80mg,口服,3次/d。疗程为1个月。并测定治疗前后血液流变学各项参数。结果病例组治疗后血小板粘附率(PadT)、血栓长度、重量与对照组比较均有显著性差异(P均<0.01);治疗后红细胞刚性指数(IR)、血沉(ESR)、红细胞电泳时间(EFT)、全血表现粘度(BAV)与治疗前比较均有显著性差异(P均<0.001);病例组治疗后红细胞比积(HCT)、纤维蛋白原(Fib)、血浆比粘度(PV)与对照组比较均无显著性差异(P均>0.05)。结论小剂量阿司匹林与银可络联合治疗对血栓形成过程有抑制作用,红细胞变形能力和聚集性有所改善。但对Fib,PV,HCT无影响。 相似文献
74.
Abstract – In the treatment of crown fractures, adhesive fragment reattachment provides a good alternative to other restorative techniques, offering several advantages. The present paper reports a case in which the treatment of a cervical crown fracture was accomplished by reattaching the tooth fragment with a flowable resin composite. Orthodontic root extrusion was performed with a modified Hawley appliance prior to fragment reattachment. The clinical and radiographic results after 2.5 years were successful. 相似文献
75.
Receiver operating characteristic curves and accuracy parameters were computed for traditional sperm characteristics (concentration, motility, morphology) and the number of peroxidase negative cells, and the concentration of adenosine triphosphate (ATP) in semen from populations of fertile and infertile men, and men who achieved a pregnancy after varicocele treatment. The percentage and concentration per millilitre of spermatozoa with rapid linear progressive motility, and the ATP concentration, provided the best discrimination between fertile and treated fertile from infertile men. The misclassification rate was higher for sperm morphology, total progressive motility and viability, whereas sperm concentration and the total sperm count per ejaculate had the worst discriminating power. The number of peroxidase negative cells per 100 spermatozoa was highly specific in identifying men who achieved pregnancy after varicocele treatment. The lower limit of normality of sperm characteristics was remarkably different between fertile men and men achieving pregnancy after treatment or during infertility work-up. 相似文献
76.
C. Caramella F. Ferrari M. C. Bonferoni M. E. Sangalli M. De Bernardi Di Valserra F. Feletti M. R. Galmozzi 《Biopharmaceutics & drug disposition》1993,14(2):143-160
Six preparations were considered: three multiple unit dosage forms (micropellets in capsules) (D, E and G) and one matrix tablet (B) were experimental prolonged release formulations, two non-disintegrating tablets (A and C) were commercial products. The in vitro dissolution behaviour of the differing formulations was investigated using the USP XXII paddle apparatus. The in vivo study was effected on a panel of 12 healthy volunteers. The two commercial tablets (A and C) showed mean dissolution time (MDT) of 1.34 and 1.44 h and td of 91 and 92 min, respectively; for prolonged release formulations (B, E, D, and G) MDT ranged between 2.28 and 4.23 h and td between 149 and 291 min. The mean residence time (MRT) was 8.68 and 6.47 h for tablets A and C, respectively; it ranged between 9.62 and 10.24 h for the multiple unit formulations E, D, and G and was 11.27 h for matrix B. Formulation B also showed the higher apparent elimination half-life t1/2 (7.12 h), while apparent t1/2 for all the other formulations were very similar, ranging between 5.04 and 5.28 h. High variability between the various formulations was found for Cmax and AUC values, and no relationships could be established with the type of formulation. An in vitro/in vivo correlation was found for all the formulations examined on the basis of analogous parameters (MDT and MRT); (r = 0.83, p <0.05). In a few cases the Wagner-Nelson deconvolution method was applied to individual plasma level versus time curves and the corresponding absorption curves were obtained. In these cases the in vitro/in vivo correlation was tested on the basis of the comparison of the in vivo absorption curves with the in vitro dissolution profiles. This was accomplished using the ‘Levy's plot’ (per cent released versus per cent absorbed) approach and provided further support for the correlation found. 相似文献
77.
Dmitri Artemov Zaver M. Bhujwalla Ross J. Maxwell John R. Griffiths Ian R. Judson Martin O. Leach Jerry D. Glickson 《Magnetic resonance in medicine》1995,34(3):338-342
The anticancer agent temozolomide labeled with 13C (8-Carbamoyl-3-13C-methylimidazo-[5,1-d]-1,2,3,5-tetrazin-4-(3H)-one), was noninvasively detected in subcutaneous RIF-1 tumors by a selective cross polarization 13C NMR method, at a field strength of 9.4T. Pharmacokinetics of the drug, at a dose of 150 mg/kg, were determined for intravenous and intraperitoneal modes of administration (three animals per mode). The half-life of the drug in the tumors was approximately 60 min. The uptake and clearance of the drug, however, varied significantly between individual hosts, for both modes of administration. These results demonstrate the feasibility of obtaining pharmacokinetics of anticancer agents for individual tumors without the need for a label that might modify drug activity (e.g., fluorine). The variability of the in vivo measurements, even within the same tumor model, demonstrates the necessity of directly monitoring the tumor to evaluate drug pharmacokinetics. 相似文献
78.
D. McCormick 《Neuropathology and applied neurobiology》1993,19(2):146-151
There is evidence from investigations of non-CNS neoplasms that secreted proteolytic enzymes may facilitate tumour invasion by partially degrading extracellular matrix (ECM). Among the enzymes which may be involved are members of the cysteine proteinase superfamily and especially cathepsin B (CB). In the present investigation we have studied CB in human gliomas in vitro , concentrating particularly on CB secretion, as extracellular enzyme is of prime importance in this context. We have found that CB is secreted by gliomas in vitro as a latent zymogen, requiring activation. This has been confirmed by gel chromatography which indicated that CB is secreted as a 42 kDa proenzyme which may be proteolytically processed to an enzymatically active 29 kDa molecule. The inactive, high molecular weight, latent CB is stable at extracellular pH in contrast to the activated low molecular weight form which rapidly loses activity at this pH. We have also measured secretion of cysteine proteinase inhibitors (CPI), as their presence would have a direct influence on the effective activity of CB, and found that all of the gliomas secreted significant amounts of a CPI as assessed by papain inhibition. Our experiments suggest that a number of factors are involved in the regulation of extracellular glioma-derived CB activity. These include: rate of secretion of pro-CB, rate of CB activation, destabilization of CB at neutral pH and the presence of cysteine proteinase inhibitors. 相似文献
79.
本研究建立了大鼠气管上皮细胞体内-体外转化模型,大鼠气管内滴注苯并芘,三天后处死大鼠,消化气管上皮细胞,接种于无血清完全培养基。细胞形成集落后,换为选择培养基继续培养五周,统计转化率。结果显示,25mg/kg和50mg/kg的苯并芘可诱导大鼠气管上皮细胞转化及微核增加,用同样方法研究了煤焦沥青提取物,结果表明,剂量为8mg/kg和25mg/kg的煤焦沥青提取物能明显诱导大鼠气管上皮细胞转化。 相似文献
80.
G. Rosa G. Pinto P. Orsi R. A. de Blasi G. Conti R. Sanit I. La Rosa A. Gasparetto 《Acta anaesthesiologica Scandinavica》1995,39(1):90-95
Postoperative shivering may be prevented by maintaining normothermia intraoperatively or it may be treated using specific drugs. The aim of this study was to compare the efficacy of nefopam hydrochloride (nefopam) to that of clonidine and meperidine in patients undergoing elective neurosurgical procedures. Three groups of patients were included in the study. Patients in group A (60) received i.v., at random, 20 mg of nefopam, 50 mg of meperidine or 150 μg of clonidine in the immediate postoperative period. The incidence of shivering and the time at which shivering ceased were noted, along with central temperature and main haemodynamic changes. Group B (20) received i.v., at random, either 10 mg of nefopam or saline before awakening from anaesthesia. The effects of nefopam on central temperature, oxygen consumption (Vo2), carbon dioxide production (VcO2), basal metabolic rate (BMR) and energy expenditure (EE) were investigated. Group C (10) received i.v. 20 mg of nefopam during surgery: cerebrospinal fluid pressure (CSFP), cerebral perfusion pressure (CPP) and electroencephalogram (EEG) were monitored. In group A nefopam stopped shivering in 95% of patients when compared to meperidine and clonidine, which were effective in 32% and 40% of patients respectively. In group B, only 10% of patients receiving nefopam had postoperative shivering, Vo2, VcO2 and EE were significantly lower in patients treated with nefopam than those in the control group. No changes in CSFP, CPP or EEG were observed in group C. In conclusion, nefopam seems to be more effective than clonidine or meperidine in quickly suppressing shivering, without producing significant adverse reactions. 相似文献