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991.
目的 探讨血清骨膜蛋白(PN)和骨硬化蛋白(SOST)与老年 2 型糖尿病(T2DM)患者骨密度的关系。方法 选取2020年8月—2022年3月海南医学院第二附属医院收治的192例老年T2DM患者作为研究对象,依据骨密度值分为骨量正常组、骨量减少组及骨质疏松组,每组64例。比较3组患者的临床资料,血清PN、SOST、25羟维生素D3[25(OH)D3]、骨钙素(OST)及I型胶原氨基端前肽(PINP)水平。多因素Logistic回归分析影响老年T2DM患者骨质疏松发生的危险因素。绘制受试者工作特征(ROC)曲线,以ROC曲线下面积(AUC)评价血清PN、SOST及两者联合对老年T2DM患者骨质疏松的诊断价值。结果 骨量正常组、骨量减少组及骨质疏松组HbA1c、HDL-C、PN、SOST、25(OH)D3、OST及PINP水平比较,差异有统计学意义(P <0.05),骨质疏松组HbA1c、PN、SOST、OST及PINP水平高于骨量正常组和骨量减少组(P <0.05),骨质疏松组HDL-C、25(OH)D 相似文献
992.
Rapid identification of low level hepatitis B-related viral genome in serum. 总被引:6,自引:1,他引:5 下载免费PDF全文
A sensitive and specific method has been developed to detect hepatitis B virus (HBV) in serum. The method involves two steps: the capture of viral genome from serum using a high affinity IgM monoclonal antibody directed against a common a domain epitope found on the envelope, and the amplification of viral DNA by the polymerase chain reaction (PCR). The amplification is initiated using "generic" primers derived from the core and pre-core sequences which are highly conserved amongst the hepadnaviruses. This rapid technique detects less than 10 infectious virions and may be useful in the study of individuals with acute and chronic liver disease of unknown etiology. 相似文献
993.
Current models hold that CD4+ depletion occurs as a result of direct and indirect effects of HIV, which both kill peripheral CD4+ cells and prevent adequate regeneration. Although age-associated involution diminishes thymic reserve and HIV is clearly thymotoxic, clinical trials have nonetheless shown that large proportions of patients who sustain adequate control of viral replication with highly active antiretroviral therapy (HAART) will demonstrate some evidence for thymic-dependent immune reconstitution, which is associated with improved immune competence. Furthermore, patients with insufficient or absent immune reconstitution following HAART generally lack evidence for thymopoiesis. Current studies are focused on improving our understanding of the causes for thymic failure in HIV infection. Recent work has demonstrated that some HIV strains, especially those that are CXCR4 trophic, are more thymotoxic and may contribute to irreversible thymic damage in this population. 相似文献
994.
活动性类风湿关节炎患者sICAM-1、sVCAM-1的变化及意义 总被引:2,自引:0,他引:2
目的 :测定活动性类风湿关节炎 (RA)患者血清中sICAM 1、sVCAM 1水平 ,探讨sICAM 1、sVCAM 1与IL 1、TNF、IFN γ及病情的关系。方法 :用酶联免疫分析法 (ELISA)检测 30例活动性RA患者与 30例健康对照者sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平。结果 :RA患者血清sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平明显高于正常对照组 (P<0 0 0 1) ,sICAM 1与IL 1、IFN γ正相关 ,与RF亦呈正相关 ,sVCAM 1与IL 1、TNF、IFN γ正相关 ,与ESR、CRP、Stock指数正相关。结论 :RA患者血清sI CAM 1、sVCAM 1水平显著升高 ,sICAM 1、sVCAM 1可能参与RA发病过程 ,sICAM 1可作为判断病情严重性的指标 ,sVCAM 1可作为观察病情活动性的指标。 相似文献
995.
Nitric oxide (NO) is an intra - and intercellular messenger with a broad spectrum of activities in the central nervous system, cardiovascular and immune systems. Mitochondrial nitric oxide synthase(mtNOS), which might be a new form of NOS in mitochondria, has been discovered to be active in the regulation of mitochondrial respiration, energy metabolism and manypathophysiological processes. In this review, the location, properties, physiological and pathophysiological significance of mtNOS were summarized. 相似文献
996.
Electrocardiographic imaging (ECGI) is a developing imaging modality for cardiac electrophysiology and arrhythmias. It reconstructs epicardial potentials, electrograms, and isochrones from electrocardiographic body-surface potentials noninvasively. Current ECGI methodology employs Tikhonov regularization, which imposes constraints on the reconstructed potentials or their derivatives. This approach can sometimes reduce spatial resolution by smoothing the solution. Accuracy depends on a priori knowledge of solution characteristics and determination of an optimal regularization parameter. These properties led us to implement an independent, iterative approach for ECGI—the generalized minimal residual (GMRes) method—which does not apply constraints. GMRes was applied to experimental data during activation/repolarization of normal and infarcted hearts. GMRes reconstructions were compared to Tikhonov reconstructions and to measured gold standards in isolated hearts. Overall, the accuracy of GMRes solutions was similar to Tikhonov regularization. However, in certain cases GMRes recovered localized potential features (e.g., multiple potential minima), which were lost in the Tikhonov solution. Simultaneous use of these two complementary methods in clinical ECGI will ensure reliability and maximal extraction of diagnostic information in the absence of a priori information about a patient's condition.© 2003 Biomedical Engineering Society.
PAC2003: 8719Hh, 8757Gg 相似文献
997.
Murine macrophages were treated with various doses of cyclosporin A (CsA) to enhance the killing of Leishmania major parasites. CsA reduced the rate of infected cells from 75% in non-treated controls to less than 15% with 1 micro g CsA/ml in a dose-dependent manner. The leishmanicidal effect was also observed when CsA was added 48 h after the infection of macrophages. In contrast, FK506, another structural non-related immunosuppressive drug with antiparasitic activities, showed no effect on the ability of macrophages to kill intracellular Leishmania parasites. Since nitric oxide has been identified as a key molecule for the leishmanicidal function of macrophages, we analyzed the role of this molecule. There was no influence on the leishmanicidal effect of CsA when L- N-(1-iminoethyl)lysine, a potent and selective inhibitor of mouse inducible nitric oxide synthase, was added. Furthermore, the presence of the macrophage-inhibiting cytokines interleukin (IL)-10 and IL-13 simultaneously or prior to CsA did not inhibit leishmania killing, while both cytokines completely prevented parasite killing by macrophages activated with gamma interferon and tumor necrosis factor (TNF). CsA was fully active on macrophages from TNF-receptor p55 knockout mice arguing against autocrine activation by TNF. We therefore conclude that the antileishmanial effect of CsA is independent of effector mechanisms employed by macrophage-activating cytokines. 相似文献
998.
Jacek Dabert Agnieszka Badek Maciej Skoracki 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(3):250-267
Two new genera and three new species of feather mites (Astigmata, Pterolichoidea, Analgoidea) are described from two closely
related species of cockatoos, Cacatua galerita (type host) and C. sulphurea (Psittaciformes, Cacatuidae): Astrolabelichus caudatus gen. nov., sp. nov. (Pterolichidae), Psittophagus lacunosus sp. nov. (Pterolichidae), and Cacatualges microdiscus gen. nov., sp. nov. (Xolalgidae). The presence of the same set of mite species on these two species of parrots points to
a very close affinity of Cacatua sulphurea and C. galerita and gives additional support for the recent hypothesis of the conspecificity of these birds. 相似文献
999.
Anna Okulewicz Jerzy Okulewicz Joanna Hildebrand Grzegorz Zaleśny 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(3):292-294
Three male specimens of the eyeworm, Oxyspirura chabaudi, were found during the post mortem examination of one individual of Turdus merula L. (Passeriformes). This is the first record of Turdus merula as a host for O. chabaudi. 相似文献
1000.
目的:探讨细胞外基质纤维连接蛋白(FN)、层黏连蛋白(LN)及三维基膜Matrigel胶对平滑肌细胞黏着斑激酶(FAK)表达的影响。方法:免疫荧光组织化学技术对生长在FN、LN和Matrigel胶里的平滑肌细胞FAK的表达进行检测。结果:生长存FN、LN和Matrigel胶里的平滑肌细胞FAK的表达依次为最高、次之和最低,各组之间有统计学意义;平滑肌细胞FAK磷酸化水平和FAK的表达呈正相关,生长在FN上的平滑肌细胞FAK(py397)的表达水平最高,生长在Matrigel胶里的平滑肌表达最低。结论:细胞外基质成分及其构筑对平滑肌细胞FAK的表达具有重要调节作用。 相似文献