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81.
糖尿病患者第3腰椎骨密度测量的意义   总被引:1,自引:0,他引:1  
糖尿病(DM)患者继发骨质疏松较多见,为探讨早期诊断,对30例非胰岛素依赖型糖尿病(NIDDM)患者和40例正常对照者,进行血清钙(Ca)、磷(P)、碱性磷酸酶(AKP)的测定,拍照胸部、腰椎和骨盆X线片,并分别经CT进行第3腰椎骨密度(BMD)测量。结果,DM组BMD均值为127.1±25.77mg/cm3,对照组BMD均值为189.11±71.68mg/cm3,两组比较有非常显著差异(P<0.01),提示第3腰椎骨密度测量对DM患者骨质疏松的早期诊断有一定价值。  相似文献   
82.
Cholesterol is an essential component of cellular membranes, but when present in excess in the circulation, can be deposited in the arterial wall, leading to the formation of atherosclerotic lesions. The principal plasma carrier of cholesterol, low density lipoprotein (LDL), is removed from the circulation by LDL receptors in the liver. This process plays a critical role in regulating plasma LDL levels. The unique structure and composition of the LDL particle makes it particularly susceptible to modification by oxidative reactions. Current evidence suggests that the production of oxidised LDL in the intima, and the removal of oxidised LDL particles by scavenger receptors on macrophages, play a central role in the development and progression of atherosclerotic lesions.  相似文献   
83.
The construction of a needle-shaped multiwire microelectrode is described. It can be made with simple mechanical tools. The presented electrode assembly consists of 12 insulated nichrome wires (core diameter 25 μm) which are embedded in epoxylite resin. The straight-cut wire tips are aligned lengthwise and have a relative spacing of 150 μm. Outer dimensions vary from 100 × 180 μm at the level of the 1st electrode channel, to 100 × 100 μm at the level of the 12th channel at the tip. The configuration of this electrode was determined by its application: the laminar analysis of evoked potentials in the cortex of the rat. However, the number of channels, the diameter of the (nichrome) wire which determines the surface area of these channels, and the channel spacing can be easily adjusted during construction to meet other experimental requirements, such as the recording of single-unit activity. The electrode which is composed of biocompatible materials is suited for the study of field potentials and multiple-unit activity, in both acute and chronic experiments, and can be used repeatedly. To demonstrate the performance of the electrode assembly, a depth profile of field potentials is presented, accompanied by the corresponding current source density distribution. The potentials were recorded in the somatosensory cortex of the rat following stimulation of the median nerve under ketamine anesthesia.  相似文献   
84.
目的:利用计算机对乳腺钼靶片上病灶中心及病灶周围影像光密度的测定,来探索良、恶性乳腺病变之间以及各种病变病灶中心与病灶周围影像的密度差异:探讨病理基础和临床意义。材料和方法:随机选取100例临床可扪及乳腺"肿块"的女性病人,进行乳腺钼靶X线检查,将检出病变的102张钼靶片进行计算机处理后,对病灶中心及病灶周围组织影像的光密度进行测定。所有病例除炎性病变外均取得病理结果。结果:1.良性病变的病灶中心密度与病灶周围密度无显著差异(P>0.5),良性肿块(指纤维腺瘤和囊肿)的病灶中心与病灶周围密度间仅提示一种可能存在显著差异的趋势(0.1>P>0.05);2.乳腺癌病灶中心与病灶周围密度之间存在非常显著的差异(P<0.001);3.良、恶性肿瘤病灶中心密度之间存在较显著差异(P<0.05)。结论:本研究的结果有助于乳腺良、恶性病变的鉴别诊断和提高早期乳腺癌的检出率。  相似文献   
85.
背景 随着代谢性疾病发病率的上升,代谢综合征(MS)的预防与控制引起广泛的关注。而脂质比值是重要的筛查指标之一,与MS之间的关系成为热点研究话题。目的 基于贵州省多阶段横断面研究人群分析三酰甘油/高密度脂蛋白胆固醇(TG/HDL-C)、总胆固醇/HDL-C(TC/HDL-C)、低密度脂蛋白胆固醇/HDL-C(LDL-C/HDL-C)及非高密度脂蛋白胆固醇(non-HDL-C)与MS发病风险的关联及预测价值评价。方法 回顾性选取贵州省参与2010年全国疾病监测地区慢性病及危险因素调查、2013年中国慢性病及其危险因素监测、2015年中国成人慢性病与营养监测和2018年中国成人慢性病与营养监测的21 727例自然人群为研究对象,收集研究对象的基线资料,根据是否患有MS将研究对象分为MS组(n=4 981)和非MS组(n=16 746)。绘制受试者工作特征曲线(ROC曲线)分别评价男性和女性TG/HDL-C、TC/HDL-C、LDL-C/HDL-C和non-HDL-C对MS的预测价值。通过Delong检验比较脂质比值预测MS发生的ROC曲线下面积(AUC)的差异。采用多因素Logistic回...  相似文献   
86.
This paper reviews the literature on the role of dietary fat in calorie intake and body weight gain in humans and laboratory animals. An overview of 40 animal studies which compared growth on high-fat (HF) and high-carbohydrate (HC) solid/powdered diets indicated that the HF diet elicited greater weight gain in 33 out of 40 studies. Enhanced growth on the HF diet was often, but not exclusively, attributable to greater caloric intake. Additional evidence for the growth-enhancing effect of HF diets emerges from "diet option" and "supermarket" feeding studies in rats, and experimental and epidemiological studies in humans. Three principal factors that contribute to the different responses to HF and HC diets are (a) caloric density, (b) sensory properties and palatability, and (c) postabsorptive processing. It is concluded that both calorie intake and metabolic energy expenditure are biased towards weight gain when a HF diet is consumed, and that the high caloric density of high-fat diets plays a primary role in weight gain. Humans may be biologically predisposed to gain weight when a HF diet is consumed.  相似文献   
87.
目的:观测纯静脉皮瓣术后血流量和血管网面密度变化。方法:利用家兔耳背设计纯静脉皮瓣和动脉皮瓣模型①观测术后血流量;②墨汁灌注后软蜡厚蜡切片,图像分析血管网面密度。结果:①纯静脉皮瓣术后48h血流量最低,第14d恢复至术前65%。②纯静脉皮瓣术后第1~7d的血管网面密度高于动脉皮瓣(P<0.05)。结论:纯静脉皮瓣术后血流量及血管网密度变化与动脉皮瓣不同。  相似文献   
88.
Early erythroid precursors were studied in human bone marrow smears to provide more information on small proerythroblasts--"microproerythroblasts"--using a silver reaction to demonstrate silver stained nucleolar organizer regions (AgNORs) and light microscopic densitometry of large irregularly shaped nucleoli and cytoplasm stained for RNA. No significant differences were found for the density of such nucleoli and basophilic cytoplasm between characteristic large proerythroblasts with a nuclear diameter larger that 9 microm (K2 and K1 erythroblasts) and small proerythroblasts--"microproerythroblasts" representing a subpopulation of K1/2 erythroblasts (early basophilic erythroblasts), which are characterized by a smaller nuclear diameter. In addition, large irregularly shaped nucleoli of "microproerythroblasts" possessed numerous silver stained particles representing AgNORs similar to those of large proerythroblasts. The number of AgNORs in "microproerythroblasts" was slightly, but significantly, smaller than that in large characteristic proerythroblasts.  相似文献   
89.
A reduction in interleukin-6 (IL-6) activity may contribute to the beneficial effects of hormone replacement therapy (HRT) on the menopausal decline in bone mineral density (BMD). We have examined this hypothesis using a genetic strategy. The –174C (rather than G) IL-6 gene variant is associated with lower IL-6 expression. As such, we might anticipate the C allele to be associated with a greater response to HRT. We have tested this hypothesis. Mean three-site [spine (L1-L4), neck of femur, and Wards triangle] BMD was measured in 65 women in a 1-year randomised controlled trial of HRT with 0.625 mg oestrogen/day and 0.15 mg norgestrel (n=30). Baseline BMD was genotype-independent for both the control and HRT group. In the control group, the percentage change in BMD after 1 year was similar between genotypes (P=0.45). In contrast, in the HRT group, the rise was genotype-dependent. Those homozygous for the G allele showed a 3.62 (2.14)% increase in BMD compared with 10.44 (4.68)% for the C-homozygous group. Heterozygotes had an intermediate BMD increase of 5.6 (2.82)% [P=0.006 (P value for interaction between HRT and genotype was 0.04)] Although the study was limited by its small sample size, these are the first data to demonstrate the importance of IL-6 genotype in determining response to oestrogen therapy, rather than its physiological withdrawal.  相似文献   
90.
为探讨甲状腺功能亢进(甲亢)患者骨代谢指标与甲状腺激素水平的变化, 本文对70例甲亢患者及60名健康对照者采用放射免疫分析法(RIA)测定了Ⅰ型胶原羧基末端肽(ICTP), 全自动微粒子化学发光分析法测定了骨碱性磷酸酶(BAP)及甲状腺激素(T3、T4、FT3、FT4)水平, 同时用二维骨密度仪测定骨密度(BMD).结果表明: 甲亢患者血清BAP、ICTP与甲状腺激素水平均明显高于健康对照组(P均小于0.01), 骨密度(BMD)则显著低于健康对照组(P<0.01).相关分析显示, 甲亢患者血清BAP、ICTP水平与BMD呈明显负相关(r分别为-0.298和-0.276, P<0.05), 与T3呈正相关(r分别为0.452和0.531,P<0.01), 与T4亦呈正相关(r分别为0.419和0.398, P<0.01).提示甲亢患者骨转换增强, 并以骨吸收增加更为显著, 与甲亢时甲状腺激素分泌过多有关. 定量检测血清BAP、ICTP水平对于甲亢代谢性骨病的诊断、病情研究均有重要的临床价值.  相似文献   
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