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71.
王文志 杨定焯 蒋建军 吴涛 程晓光 周琦 卓铁军 张华俦 项静 王洪复 区品中 刘建立 徐苓 黄公怡 黄琪仁 HS Barden LS Weynan KG Fqukner 孟迅吾 《中国神经再生研究》2008,12(50):9997-10000
背景: 不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。
目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。
设计、时间及地点:调查分析,于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。
对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析;男3 666人,女7 752人;年龄20岁~90岁;分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。
方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。
主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。
结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01 g/cm2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化 0.01 g/cm2,则骨质疏松症检出率变化4%(呈负相关)。
结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。 相似文献
72.
73.
74.
Krimer LS; Hyde TM; Herman MM; Saunders RC 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):722-731
The entorhinal cortex (ERC) has been implicated in the pathophysiology of
Alzheimer's disease, schizophrenia and other disorders affecting cognitive
functions. While powerful anatomical and histochemical methods
(immunohistochemistry, in situ hybridization, etc.) may be applied
(although with limitations) to postmortem human brain, each analysis should
utilize a cytoarchitectonic approach to provide appropriate comparisons
within the subdivisions of the ERC. Accordingly, we describe here the
normal cyto- and myeloarchitecture of the human ERC as a prerequisite for
the accompanying study of this region in schizophrenia. Our parcellation of
this cortex differs from previous treatments in three ways. First, we
adopted specific criteria of inclusion to define each subdivision of the
region. Although distinctive ERC features are most prominent in the
intermediate portion of this region, at least one of these features was
considered the minimum necessary criterion to include adjacent tissue in
the entorhinal area. Second, we used morphometric measurements (neuronal
size and density as well as subdivisional volume and laminar thickness) to
support our qualitative evaluation. Third, we have applied to the human ERC
the conventional cytoarchitectonic nomenclature of the entorhinal cortex
used previously in studies of non-human primates. This allows a more
accurate extrapolation of the available numerous experimental anatomical,
physiological and psychological data on this region to the human. As in the
monkey, the five main subareas were recognized in the human (prorhinal,
lateral, intermediate, sulcal and medial) but three required further
subdivision (intermediate, sulcal and medial). The morphometric results
obtained suggested a progression of the human entorhinal cortex from the
peripheral to the central subareas, with the intermediate subarea (281) as
the most complete entorhinal subdivision. Compared with non-human primates,
the human ERC not only retains the basic periallocortical organization but
also demonstrates further evolution. Taken together with available
experimental data on the connectivity of this brain region, these results
provide an anatomical basis for evaluating the ERC in human behavior.
相似文献
75.
Colin T Walsh Yong Wei M Guillaume Wientjes Jessie LS Au 《Journal of translational medicine》2008,6(1):4
Background
The role of basic fibroblast growth factor (bFGF) in chemoresistance is controversial; some studies showed a relationship between higher bFGF level and chemoresistance while other studies showed the opposite finding. The goal of the present study was to quantify bFGF levels in archived tumor tissues, and to determine its relationship with chemosensitivity. 相似文献76.
硝基甘油对狗缺血区冠脉循环的作用 总被引:1,自引:0,他引:1
用实验性犬冠脉狭窄模型,冠脉内恒流灌注硝基甘油0.5μg/kg.min-1,使冠脉血流量(CBF)增加、远端小动脉压(DCP)、冠脉血管总阻力(RT)、小冠脉血管阻力(RS)及冠状静脉低切血粘(ηb)减少;而主动脉压和心率无明显变化。恒流灌注硝基甘油1μg/kg.min-1时,在开始5min内冠脉循环的变化同上,并伴大冠脉血管阻力(RL)减少,10 min后出现CBF减少和RT,RL及ηb增加。结果提示,硝基甘油有缓解和加重心肌缺血的双重作用,其作用可能与剂量张扩张远端小动脉压的程度有关。 相似文献
77.
O. DANIËLS J. HOPMAN S. DE KNECHT A. VAN OORT H. BUSCH 《Acta paediatrica (Oslo, Norway : 1992)》1986,75(S329):44-52
ABSTRACT. The pulsed Doppler principle enables us to study the bloodflow velocity at specific points in the heart and great vessels. In such aorto-pulmonary connections as patent dnctus arteriosus, aorto-pulmonary window and truncus arteriosus the bloodflow velocity patterns are typical of the malformation. Based on knowledge of these abnormal flow patterns the diagnoses of these malformations can be made. 相似文献
78.
79.
Matthew J Thurtell FRACP Alison LS Chiu FRANZCO Lucy A Goold MM Gulden Akdal MD John L Crompton FRANZCO Rebekah Ahmed FRACP Simon N Madge FRCOphth Dinesh Selva FRANZCO Ian Francis FRANZCO Raf Ghabrial FRANZCO Arj Ananda FRACS John Gibson FRACP Raymond Chan FRACP Elizabeth O Thompson FRANZCR Michael Rodriguez FRCPA Peter J McCluskey FRANZCO G Michael Halmagyi FRACP 《Clinical & experimental ophthalmology》2013,41(6):567-576
80.
BR Kurnik RL Allgren FC Genter RJ Solomon ER Bates LS Weisberg 《American journal of kidney diseases》1998,31(4):674-680
Radiocontrast-induced nephropathy (RCIN) is a common cause of hospital-acquired acute renal failure and is associated with a high mortality rate. RCIN is potentially preventable, because administration of the radiocontrast agent is predictable, and a high-risk population has been identified. This multicenter, prospective, randomized, double-blind, placebo-controlled trial was performed to evaluate the efficacy of intravenous atrial natriuretic peptide (anaritide, ANP 4-28) to prevent RCIN. Patients with stable chronic renal failure (serum creatinine greater than 1.8 mg/dL or serum creatinine between 1.5 and 1.8 mg/dL with estimated creatinine clearance of < or = 65 mL/min) were assigned to receive either placebo or one of three doses of anaritide (0.01 microg/kg/min, 0.05 microg/kg/min, or 0.1 microg/kg/min) for 30 minutes before and continuing for 30 minutes after radiocontrast administration. All patients were given intravenous 0.45% saline for 12 hours before the radiocontrast procedure and continuing for 12 hours after the last dose of radiocontrast. Both ionic and nonionic radiocontrast agents were administered. RCIN was defined as either an absolute increase of serum creatinine of > or = 0.5 mg/dL or a percent increase of > or = 25% over baseline. Of the 247 patients who completed the study, 50% had diabetes mellitus. There were no statistical differences in baseline serum creatinine, change in serum creatinine, or the incidence of RCIN. The incidence of RCIN was placebo, 19%; anaritide (0.01), 23%; anaritide (0.05), 23%; anaritide (0.1), 25%. Patients with diabetes mellitus had a significantly greater incidence of RCIN: placebo, 26% versus 9%; anaritide (0.01), 33% versus 13%; anaritide (0.05), 26% versus 21%; anaritide (0.1), 39% versus 8% (diabetic v nondiabetic, P < 0.002). There was no effect in the diabetic or nondiabetic groups by anaritide on the incidence of RCIN. Comparison of the highest-risk group of patients, defined as patients with diabetes mellitus and a baseline serum creatinine > or = 1.8 mg/dL, with the lowest-risk group, defined as patients without diabetes mellitus and a baseline serum creatinine of 1.8 mg/dL or less, did not show a beneficial effect of anaritide administration. In conclusion, administration of intravenous anaritide before and during a radiocontrast study did not reduce the incidence of RCIN in patients with preexisting chronic renal failure, with or without diabetes mellitus. 相似文献