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It has previously been shown that it is possible to differentiate between squamous and columnar epithelia in rat and resected human tissues using an impedance probe to makein vitro measurements. This probe can be passed down an endoscope allowing measurements to be made in patients. However, the probe emerges parallel to the oesophageal wall, with little room to manoeuvre. The conditions of control required to give reliable readings have been investigated. The importance of pressure applied and the angle of approach to the oesophagus was assessed. Pressures in the range 26.6 Pa to 46.3 kPa and angles in the range 15–90 degrees were considered. Inin vitro studies it was observed that it was possible to obtain consistent readings with pressures greater than 2.9 kPa and with angles greater than 15 degrees between the probe and the oesophagus. These conditions can be achievedin vivo, and readings obtained from twelve patients are shown (45 readings on normal squamous, 34 on Barrett's oesophagus and 22 on stomach). At low frequencies (9.6–153.2 kHz), a Mann-Whitney test shows a significant difference (p<0.001) when comparing the means from squamous and columnar, and also when readings from Barrett's and normal gastric epithelia are compared (p<0.001).  相似文献   
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玻璃体切除术治疗外伤性眼内炎62例   总被引:3,自引:1,他引:2  
王金兰  蒋宏苏  惠延年 《医学争鸣》2000,21(2):S018-S018
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿…  相似文献   
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Large clinical trials have repeatedly proven the effectiveness of highly active antiretroviral therapy (HAART) in achieving virological suppression; however, subsequent increases in CD4 cell counts (i.e., immunological rebound) do not always follow. Thus, it remains unclear to what extent persons living with HIV/AIDS may expect significant increases in CD4 cell count upon HAART initiation, particularly outside of the highly structured environment of a clinical trial. We analyzed the patterns of CD4 and plasma viral load (PVL) change in 170 HIV-infected individuals who were ART naive and initiated HAART between 1997 and 2003. Immunological success (>50 CD4 cells/mm(3) increase) was evaluated using Kaplan-Meier survival analysis and Cox proportional hazard models. Of individuals, 80% experienced a confirmed CD4 cell count increase of >50 cells/mm(3) after HAART initiation. Multivariate analysis showed that patients with pre-HAART PVL >or=100,000 copies/ml were more likely to achieve immunological success when compared with patients with baseline PVL <10,000 copies/ml, suggesting that individuals with the highest HIV viral load levels may benefit the most from HAART initiation. Future studies of immunological rebound are warranted to further define and characterize immune responses to HAART in diverse populations in order to optimize guidelines for initiation of treatment and assessment of successful responses.  相似文献   
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Curcumin has been transformed to several diversely substituted bis-pyrrolizidino/thiopyrrolizidino oxindolo/acenaphthyleno curcuminoids via a sequential azomethine ylide cycloaddition reaction using isatins/acenaphthoquinone and proline/thioproline as the reagents. The products were separated via extensive chromatography and characterized by 1D/2D NMR and HRMS analysis.

Curcumin has been transformed to several diversely substituted bis-pyrrolizidino/thiopyrrolizidino oxindolo/acenaphthyleno curcuminoids via a sequential azomethine ylide cycloaddition reaction.  相似文献   
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Neurotransmitters other than dopamine are recognized as having modulatory roles within the basal ganglia and can influence the basal ganglia dopaminergic system to alter activity of the direct and indirect pathways. Many nondopaminergic neurotransmitter systems have been implicated in the mechanisms contributing to the motor features of Parkinson's disease (PD). Thus, it is now well established that neurotransmitter systems, including glutamatergic, GABAergic, cholinergic, noradrenergic, serotonergic, opioidergic, histaminergic, and adenosinergic systems, are affected in the pathogenesis of PD. Nondopaminergic neurotransmitter systems are thus targets for the development of novel therapies for motor symptoms and motor complications in PD. Over the last 5 years, more than 20 randomized, control trials (RCTs) in PD investigating drugs that target several of these nondopaminergic neurotransmitter systems for the treatment of motor features have been completed. There are at least 15 additional RCTs that are ongoing or planned. Here, we review these RCTs to highlight the potential nondopaminergic pharmacological therapies for treatment of motor features of PD. Nondopaminergic drugs are not expected to replace dopaminergic strategies, but further development of these drugs will likely yield novel approaches with positive clinical implications. © 2012 Movement Disorder Society  相似文献   
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Diabetes mellitus (DM) is a gradually rising metabolic disease which is currently affecting millions of people worldwide. Diabetes is associated with various complications like nephropathy, neuropathy, retinopathy, diabetic foot, cognitive impairment, and many more. Evidence suggests that cognitive dysfunction is a rising complication of diabetes which adversely affects the brain of patients suffering from diabetes. Age-related memory impairment is a complication having its major effect on people suffering from diabetes and Alzheimer's. Patients suffering from diabetes are at two times higher risk of developing cognitive dysfunction as compared with normal individuals. Multiple factors which are involved in diabetes related complications are found to play a role in the development of neurodegeneration in Alzheimer's. The problem of insulin deficiency and insulin resistance is well reported in diabetes but there are many studies which suggest dysregulation of insulin levels as a reason behind the development of Alzheimer's. As the link between diabetes and Alzheimer disease (AD) is deepening, there is a need to understand the plausible tie-ins between the two. Emerging role of major factors like insulin imbalance, advanced glycation end products and micro-RNA's involved in diabetes and Alzheimer's have been discussed here. This review helps in understanding the plausible mechanism underlying the pathophysiology of amyloid beta (Aβ) plaque formation and tau hyperphosphorylation as well provides information about studies carried out in this area of research. The final thought is to enhance the scientific knowledge on this correlation and develop future therapeutics to treat the same.  相似文献   
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