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三磷酸腺苷结合盒运转体A1与颈动脉粥样硬化斑块的关系   总被引:4,自引:0,他引:4  
目的 探讨三磷酸腺苷结合盒运转体A1(ATP binding cassette transporter A1,ABCA1)在人颈动脉粥样硬化斑块中的表达变化及作用机制.方法 收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本(对照组),采用RT-PCR测定ABCA1 mRNA和视黄酸X受体α(RXRα)mRNA表达水平,并采用Western Blot检测ABCA1及RXRα的蛋白表达水平.24例人颈动脉粥样硬化斑块标本按病理分级,比较病理组织为Ⅲ级和Ⅰ级动脉粥样硬化组织间ABCA1 mRNA、RXRαmRNA表达水平及蛋白表达水平.结果 颈动脉粥样硬化斑块组的ABCA1 mRNA(0.79±0.04)和RXRα mRNA(0.73±0.04)表达与对照组相比上调,差异有统计学意义(P<0.05);ABCA1 mRNA与RXRα mRNA增加水平相关(P<0.05);颈动脉粥样硬化斑块的ABCA1蛋白表达(0.22±0.03)下调水平与对照组(0.53±0.03)相比差异有统计学意义(P<0.05);Ⅲ级和Ⅰ级动脉硬化斑块ABCA1mRNA、RXRα mRNA及蛋白表达水平差异有统计学意义(P<0.05).结论 ABCA1及RXRα蛋白表达水平下调可能是进展性动脉粥样硬化损害的关键因素.  相似文献   
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Background The Retinal Thickness Analyser (RTA) is intended to detect glaucomatous changes as well as macular pathologies at the posterior pole. We determined the diagnostic accuracy for eyes with manifest glaucoma or macular diseases.Methods We examined 71 eyes with long-term, established eye conditions. Included were 28 eyes with glaucoma, 21 with different macular diseases and 22 normal eyes. All examinations were evaluated in a blind-test by RTA experts without any clinical information on the patients. After comparison of the RTA interpretation with the clinical diagnosis, we determined sensitivity, specificity, positive and negative predictive values.Results Of 71 examinations, 15 (21%) were not interpretable. If these results are excluded, the following diagnostic accuracy values were calculated for glaucoma and macular disorders respectively: sensitivity 75 and 59%, specificity 55 and 97%, positive predictive value 48 and 90% and negative predictive value 80 and 84%. These values were not significantly different when both eyes of each patient were included in the final analysis (n=133).Conclusion The diagnostic values of the RTA determined in this case control study were not satisfactory. However, no clinical information was used in the assessment. The extent to which additional clinical information increases the diagnostic value remains to be determined.  相似文献   
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设计并试制了一种药用胶带纸层厚度在线检测系统.该系统将高精度电容传感器与计算机结合起来,同时配有丰富的外围器件,实现了多种实际生产中所需要的功能.它的出现,彻底解决了药用胶带纸胶层厚度在线检测这个难题,经过两年多的实际应用的检验,该系统实现了在线非接触测量,精度高,动态性能好,实现功能全面,价格合理,是药用胶带纸生产的必备检测仪器.由于该系统还可以很方便在纸张、塑料薄膜等其它生产线上进行推广,因而,其应用前景十分看好.  相似文献   
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Summary The prevalence of smoking, hypertension and diabetes mellitus was assessed in 221 patients suffering from internal carotid stenosis and compared with the prevalences in two sex- and age-matched control groups composed of subjects having normal Doppler findings and from non-neurological outpatients. Of the subjects with carotid stenosis 27.6% were hypertensive smokers in comparison with 9.5% and 17.2% in the two control groups. The difference of the stenosis cohort from the two control groups was significant (P<0.01 and P=0.016 respectively). There was no statistically significant differences between the occurrence of diabetes and hypertension in non-smokers and patients who smoked. In 394 investigated patients suffering from carotid stenosis or occlusion an obstruction index, based on the Doppler shift frequency, was calculated. This index was lowest in the normotentive non-smokers. It was only insignificantly higher in the hypertensive non-smokers but significantly so in the normotensive smokers. The index was highest in the hypertensive non-smokers. It was concluded that cigarette smoking, especially if associated with hypertension, is a determinant risk factor for carotid stenosis and occlusion.  相似文献   
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The central-peripheral transitional zones of rat dorsolateral vagal rootlets are highly complex. Peripheral nervous tissue extends centrally for up to several hundred micrometers deep to the brainstem surface along these rootlets. In some instances this peripheral nervous tissue lacks continuity with the peripheral nervous system (PNS) and so forms an island within the central nervous system (CNS). In conformity with the resulting complexity of the CNS-PNS interface, segments of vagal axons lying deep to the brainstem surface are myelinated by one or more intercalated Schwann cells, contained in peripheral tissue insertions or islands, at either end of which they traverse an astroglial barrier. Intercalated Schwann cells are thus isolated from contact or contiguity with the Schwann cells of the PNS generally. They are short, having a mean internodal length of around 60% of that of the most proximal Schwann cells of the PNS proper, which lie immediately distal to the CNS-PNS interface and which are termed transitional Schwann cells. The thickness of the myelin sheaths produced by intercalated Schwann cells is intermediate between that of transitional Schwann cells and that of oligodendrocytes myelinating vagal axons of the same calibre distribution. This is not due to limited blood supply or to insufficient numbers of intercalated Schwann cells, the density of which is greater than that of transitional Schwann cells. These factors are unlikely to restrict expression of their myelinogenic potential. Nevertheless, the regression data show that the setting of the myelin-axon relationship differs significantly between the two categories of Schwann cell. Thus, the myelinogenic response of Schwann cells to stimuli emanating from the same axons may differ between levels along one and the same nerve bundle. Mean myelin periodicity was found to differ between sheaths produced by intercalated and by transitional Schwann cells.  相似文献   
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There have been a few studies and inconsistent results regarding the coincidence of Parkinson's disease (PD) and atherosclerotic diseases, such as cerebrovascular disease. Carotid intima-media thickness (IMT) is a known marker for subclinical atherosclerosis. The aim of this study was to investigate the carotid IMT between PD patients and controls. We studied 43 patients with PD and 86 matched controls. The carotid IMT in PD patients was significantly smaller than in controls (0.796 +/- 0.179 mm vs. 0.913 +/- 0.237 mm, P < 0.05). In multivariate analysis, the carotid IMT was inversely associated with the duration of levodopa medication and the severity of PD. These results suggest that PD patients have a lower risk of atherosclerosis.  相似文献   
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BACKGROUND: The complaint of chronic hair loss frequently affects female subjects and there is little or no objective technology available in the general dermatology or even in the hair clinics to guide the observer in the management of the patient. The purpose of this report is to share the results of refined hair growth measurements that were collected in 92 female subjects complaining about hair loss. METHODS: Clinically they were classified as having a patterned hair loss according to Ludwig (L; n=50), diffuse hair loss (D; n=13) or no visible hair loss but complaining of hair shedding (N; n=29). Two scalp sites on the top of the head and one occipital site were investigated after clipping by close-up photography before and after a hair dye (contrast enhancement, CE). Forty-eight hours later a new photograph was taken after CE in view of phototrichogram analysis (CE-PTG). Finally a last hair clip was performed 30 days later and hair thickness and length determined for linear growth measurements (LHGR). RESULTS: Herein we confirm that the top of the head shows usually a higher hair density than occipital sites, a physiological observation that applies both to men and women. From the technological perspective, we also document that CE improves hair detection in all sites. Interestingly, in affected patients (L and D) the relative increase of hair counts after CE was much higher (range +22.4% to +28.3%) compared with apparently unaffected females (N; range +8.2% to +9.7%). This increase in hair counts was only due in part to the presence of less pigmented thinning hair (thickness less than 40 microm). Such thin hairs were found in statistically significantly higher proportions in younger patients with mildly severe (grade I) patterned alopecia (Ludwig: L). In other patients with hair loss and in more severe forms of patterned alopecia - especially in older patients - the thin hair is not detected in abnormal proportions. In all sites slower growth rates and decreased anagen percentages indicate a defective hair replacement programme distinguishing L patterns from diffuse hair loss and from apparently unaffected patients complaining of chronic hair loss. Globally, we also noted that increasing age is associated with significant regression of scalp hair (decreased hair counts, thinner hair and slower LHGR). CONCLUSION: On the basis of the present data together with female data from the literature and our own studies in male subjects, we suggest a three-step mechanism leading to hair loss 1.Shortening of growth phase the hair cycle with maintained thick hair, i.e. more frequent hair cycling that leads to more hair shedding. 2.Intermittent production of short thin hair, i.e. morphological evidence of miniaturisation. 3.Very occasional or almost no hair production, i.e. dormant follicles or irreversible follicular atrophy. Depending on the genetic background, hormonal microenvironment in the scalp and conditioning of individual hair follicle bio-responses, female and male patterned hair loss may end up into different phenotypes.  相似文献   
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