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61.
贵阳地区1?055例骨密度检测分析 总被引:13,自引:0,他引:13
采用日本阿洛卡公司双能量骨密测量仪,选择受检者桡骨远端1/3处为测量点,对贵阳地区1055例人群成人桡骨的骨密度进行测量,取得不同性别各年龄段的骨密度值,同时计算出贵阳地区成人桡骨各年龄段的骨密度均值及标准偏差。 相似文献
62.
The current article describes the design and synthesis of a new series of phosphorus-containing fluoro-sulfonated polytriazoles through click polymerization. The synthesized copolytriazoles (PTPFDSH-70 to 90) with different degrees of sulfonation (DS) from 70% to 90% are structurally interpreted by various spectroscopic techniques (1H, 13C, and FTIR). The high molecular weight (weight average molecular weight as high as 77 500 g mol−1 with polydispersity index of 2.29) polymers exhibits excellent mechanical (elongation at break up to 95%), thermal (10% decomposition temperature: 266–317 °C), and oxidative (>14.5 h) stability. The PTPFDSH-70 to 90 possess outstanding water-holding ability in hydrated conditions (swelling ratio [in-plane]: 6.2–7.3% at 80 °C). The microstructural alterations by their thermal relaxations and transitions with increasing DS in the polymers have been thoroughly investigated by dynamic mechanical analysis. The atomic force microscopy and transmission electron microscope images of the PTPFDSH-70 to 90 polymer membranes demonstrated the phase segregated interconnected ionic cluster-like morphology between hydrophilic and hydrophobic domains. The PTPFDSH-90 (DEB:PFAZ:DSAZ = 100:10:90) polymer membrane displays the proton conductivity (176 and 190 ms cm−1 at 80 and 90 °C, respectively) higher than Nafion117 under similar test conditions. 相似文献
63.
C. Kainz C. Tempfer G. Gitsch H. Heinzl A. Reinthaller G. Breitenecker 《Archives of gynecology and obstetrics》1995,256(1):23-28
The aim of the present study was to evaluate the effect of age and human papillomavirus (HPV) infection associated cellular changes on the predictive value of cervical cytology. In a group of 671 women with Papanicolaou smears suggesting low grade squamous intraepithelial lesion (LSIL), high grade squamous intraepithelial lesion (HSIL) or invasive cervical cancer, cervical cytology was correlated with the histological finding. Predictive values were calculated and related to severity of the lesion, age and HPV associated changes. The predictive values of Papanicolaou (cervical) smears suggesting LSIL, HSIL and invasive carcinoma were 40%, 86%, and 78%, respectively. A poor predictive value of smears suggesting LSIL was found among older women. HPV associated changes were diagnosed in 80% of women 25 years of age, 66% in the age group 26 to 35 years, 51% in the age group 36 to 45 years and 38% in women aged 46 years (P = 0.03). The presence of HPV associated cellular changes led to a significantly higher number of overdiagnoses (9% with HPV infection compared to 4% without HPV infection) and HPV negative cases were more frequently associated with underdiagnosis (15% without HPV infection compared to 8% with HPV infection,P = 0.0011). This result remained significant after adjustment for age (P = 0.004). Cellular changes associated with HPV infection most frequently occurred in young women. HPV infection should therefore be acknowledged as source of overdiagnosis in the cytological evaluation of SIL especially in woung women.Supported by the Research Grant of the Mayor of Vienna (no. 1045 [to Dr. Kainz]) 相似文献
64.
Urinary delta-aminolaevulinic acid (-ALA) excretion was evaluated in random urine samples of 191 healthy children, aged 2–14 years, with blood lead levels <0.8 mol/l (mean ± SD: 0.34±0.13), erythrocyte zinc-protoporphyrin <70 mol/mol haem (mean ± SD: 50.4±8.0) and blood haemoglobin >6.8 mmol/l (mean ± SD: 8.2±0.5). It was found that uncorrected -ALA concentration and -ALA/creatinine ratio are age-dependent, whereas the ratio of -ALA/logarithm of creatinine concentration (mean ± SD: 55.3±13.5 mol/log mmol) is independent of age and sex. The authors recommend the use of this parameter for the assessment of -ALA excretion in random urine samples in children 相似文献
65.
Characteristics of bone mineral density and soft tissue composition of obese Japanese women: Application of dual-energy X-ray absorptiometry 总被引:2,自引:0,他引:2
We studied the characteristics of bone mineral density (BMD) and soft tissue composition in obese Japanese women using dual-energy
X-ray absorptiometry. Eighty-nine women, aged 45–85 years, were divided into three groups according to their body mass index
(BMI): a thin group (n = 38; BMI < 21), a standard weight group (n = 31; BMI, 21–25), and an obese group (n = 20; BMI ≥ 25). The mean BMD of the second to fourth lumbar vertebrae and BMD of the lumbar spine, thoracic spine, pelvis,
legs, and ribs of the thin group were significantly lower than those of the standard weight group or the obese group (P < 0.05), whereas no significant difference in total body BMD was observed among the three groups. There was a significant
difference in total and regional fat mass among the three groups (P < 0.05). Lean mass of legs and total lean mass showed a significant difference between the thin group and the obese group
(P < 0.05). The results showed that obesity was associated with higher BMD of weight bearing-bones and ribs, high total and
regional fat mass, and high lean mass of bilateral legs and total lean mass. We suggest that obesity may contribute to the
prevention of bone loss of weight-bearing bones and ribs and muscular atrophy of the legs.
Received: Sept. 30, 1998 / Accepted: Dec. 10, 1998 相似文献
66.
In this prospective study, birth weight of 304 babies born at Kamla Nehru Hospital Pune during study period was recorded.
From these 304 babies, babies with birth weight above 2000 grams were selected (260 babies) to prepare growth velocity curves.
Daily weight of these 260 babies was recorded for 30 days. The mean birth weight of study population was 2742.5 grams. Among
the daily weight recorded babies, all the babies lost weight ranging from 92 to 218 grams (mean 121 grams) after birth. The
weight loss continued upto 5 days. Days required to gain weight equal to birth weight ranged from 5 to 13 days. Total weight
gain observed in 30 days was 734.7 grams. Predictive value of these curves was tested in 49 infants. Deviation upto 50 grams
of predicted birth weight from actual birth weight was observed in 90% of babies on day-2, 79% on day-4, 65% on day-8 and
39% on day-30. 相似文献
67.
Frog motoneurons were intracellularly labelled with cobaltic lysine in the brachial and the lumbar segments of the spinal cord, and the material was processed for light microscopy in serial sections. With the aid of the neuron reconstruction system NEUTRACE, the dendritic tree of neurons was reconstructed and the length and surface area of dendrites measured. The surface of somata was determined with the prolate - oblate average ellipsoid calculation. Corrections were made for shrinkage and for optical distortion. The mean surface area of somata was 6710 microm2; lumbar motoneurons were slightly larger than brachial motoneurons. The mean length of the combined dendritic tree of brachial neurons was 29 408 microm and that of lumbar neurons 46 806 microm. The mean surface area was 127 335 microm2 in brachial neurons, and 168 063 microm2 in lumbar neurons. The soma - dendrite surface area ratio was 3 - 5% in most cases. Dendrites with a diameter of = 1.0 microm constituted approximately 75% of the combined dendritic length in most of the neurons. Unlike in the cat, there was no correlation between the size of stem dendrites and the extent of daughter branches. From the synaptic density estimated in earlier electron microscope investigations of frog motoneuron dendrites (Antal et al., J. Neurocytol., 15, 303 - 310, 1986; 21, 34 - 49, 1992), and from the present data, the number of synapses on the dendritic tree was calculated. The calculations indicated 26 949 synapses on the smallest and 61 519 synapses on the largest neuron if the synaptic density was multiplied by the length of the dendritic tree. If the synaptic density was multiplied by the surface area of the dendritic tree the calculation yielded 23 337 synapses for the smallest and 60 682 synapses for the largest neuron. More than 60% of the combined surface area of dendrites was >600 microm from the soma. This suggests that about two-thirds of the synapses impinged upon distant dendrites >600 microm from the soma. The efficacy of synapses at these large distances is investigated on model neurons in the accompanying paper (Wolf et al., Eur. J. Neurosci., 4 1013 - 1021, 1992). 相似文献
68.
Jeri W. Nieves Felicia Cosman Chris Mars Robert Lindsay 《Calcified tissue international》1992,51(5):352-355
Summary Forearm bone mineral density (BMD) was measured at proximal and distal sites by 125I single photon absorptiometry (SPA) and by dual energy X-ray absorptiometry (DXA) in 67 consecutive subjects, aged 18–75 years. Correlations and regression equations between these two techniques were determined. All forearm measurements were significantly correlated with each other (r=0.599–0.926; P0.0001). Although SPA and DXA correct for fat in different ways, we found similar correlation and regression equations in women with body mass index measurements above and below the mean. In addition, forearm measurements by both techniques were moderately correlated with vertebral spine and hip BMD. We conclude that overall, SPA forearm measurements in a population can be calibrated to DXA measurements if necessary, and that DXA forearm measurements are as predictive of the remainder of the skeleton as SPA measurements. 相似文献
69.
70.
VEGF,PDGF和MVD在喉癌中的表达及临床意义 总被引:3,自引:2,他引:3
目的 探讨血管内皮生长因子(vascular endothelial growth factor,VEGF),血小板来源的内皮生长因子(platelet-derived endothelial growth factor,PDGF),Ⅷ因子测定的微血管密度(microvessel density,MVD)与喉癌微血管生成、临床分期和病理分级的关系。方法 应用免疫组织化学LASB法检测1998~1999年40例喉鳞状细胞癌和11例喉正常粘膜VEGF、PDGF、微血管密度的表达情况,结合临床相关因素进行统计分析。结果 喉鳞状细胞癌中VEGF表达在肿瘤T分级、临床分期、淋巴结转移和病理分级中有统计学意义(P<0.05)。PDGF计数标识指数与病人肿瘤T分级、临床分期中差异有统计学意义(P<0.05)。MVD测定均数在早、晚期分组中有统计学意义(P<0.05)。结论 喉癌的发展、侵袭需要持续的新生血管,本实验提示肿瘤增殖与理论相符,VEGF、PDGF和MVD可作为临床预测重要参考指标。 相似文献