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101.
Digestive Diseases and Sciences - There are limited data on noninvasive methods to identify hepatic steatosis in coexisting hepatitis B virus (HBV) infection. To evaluate the diagnostic performance...  相似文献   
102.
Five isolates of Cryptosporidium parvum collected from human, horse, and calf sources were compared for differences in sporozoite protein patterns by using two-dimensional gel electrophoresis. Silver-stained two-dimensional gels contained over 300 protein spots from detergent-solubilized sporozoites. A distinguishing 106-kilodalton peptide that shifted in isoelectric point was detected in four of the five isolates. Computerized two-dimensional gel analysis was performed to obtain objective quantitation of the pI shift. Three of these four isolates could be differentiated from one other by the pI shift in this peptide. The fifth isolate was distinguished by the absence of the 106-kilodalton peptide and the presence of a 40-kilodalton peptide that was not observed in any other isolate.  相似文献   
103.
Strain‐dependent induction of allergic rhinitis without adjuvant in mice   总被引:1,自引:0,他引:1  
BACKGROUND: To date, no murine models have been reported to show the induction of both antigen-specific IgE and nasal eosinophilia, two of the major hallmarks of allergic rhinitis, after local sensitization in the absence of adjuvants, a phenomenon which reflects natural exposure. In this report, we attempted to establish a murine model representing an initiation of allergic rhinitis. METHODS: BALB/c, CBA/J, and C57BL/6 mice were sensitized intranasally to Schistosoma mansoni egg antigen (SEA) solely. After repeated sensitization, serum Ab titers, nasal eosinophilia, and cytokine production by nasal lymphocytes were determined. RESULTS: BALB/c mice produced SEA-specific IgE after repeated sensitization. High-dose sensitization to SEA induced IgE production in CBA/J mice, while C57BL/6 mice did not show the production throughout the period observed, suggesting that IgE production was regulated genetically. BALB/c mice also exhibited nasal eosinophilia after the nasal challenge. In addition, nasal lymphocytes sensitized with SEA intranasally produced significant amount of IL-5 in vitro. CONCLUSIONS: These results suggest that intranasal sensitization with SEA in the absence of adjuvants induces a Th2 immune reaction, reflecting the hallmarks of the initiation of allergic rhinitis both in vivo and in vitro, which is genetically regulated.  相似文献   
104.
原发性肉碱缺乏致脂质沉积性肌病的临床与病理特点   总被引:1,自引:0,他引:1  
目的 分析原发性肉碱缺乏致脂质沉积性肌病(LSM)的临床与病理特点。方法 回顾性分析4例可能LSM患者的临床资料。结果 本组患者为亚急性或慢性起病,主要表现为近端肌无力,疲劳不能耐受;血清肌酶有不同程度的升高;肌电图示肌源性损害;病理检查示肌纤维内可见大量细小空泡和裂隙形成;MGT染色无破碎红纤维,油红O染色显示空泡为大量脂滴充填;受累纤维以Ⅰ型纤维为主。电镜证实肌纤维内脂滴堆积,可伴有线粒体的轻度增多。改善能量和糖皮质激素治疗有效。结论原发性肉碱缺乏致LSM是一种以易疲劳和肌无力为主要临床表现的脂质代谢障碍性肌病,病理改变以肌纤维内脂滴堆积为主,一般不伴有线粒体结构的明显异常。糖皮质激素治疗可获得良好疗效。  相似文献   
105.
目的 探讨保乳手术联合腔镜腋窝淋巴结清扫术(MALND)对乳腺癌患者上肢功能、应激反应及血管细胞黏附分子-1 (VCAM-1)、细胞间黏附分子-1(ICAM-1)水平的影响。方法 回顾性分析98例乳腺癌患者的临床资料,依据手术方式的不同分为研究组53例和对照组45例。对照组行保乳手术联合传统腋窝淋巴结清扫术(CALND),研究组行保乳手术联合MALND。比较2组术前、术后6个月上肢功能;收集2组患者术前、术后12 h焦虑自评量表(SAS)、抑郁自评量表(SDS)评分以及心率(HR)、平均动脉压(MAP)水平,并对比2组应激反应程度;比较2组患者术前、术后5 d VCAM-1、ICAM-1水平。结果 术后6个月,研究组前屈、后伸、内收、外展、内旋、外旋活动角度大于对照组,差异有统计学意义(P<0.05);术后12 h,研究组SAS、SDS评分及HR、MAP水平低于对照组,差异有统计学意义(P<0.05);术后5 d,研究组VCAM-1、ICAM-1水平低于对照组,差异有统计学意义(P<0.05)。结论 保乳手术联合MALND对乳腺癌患者上肢功能影响小,术后应激反应程度轻...  相似文献   
106.
The on-alpha ganglion cell in the area centralis of the cat retina receives approximately 450 synapses from type b1 cone bipolar cells. This bipolar type forms a closely spaced array (9 microns), which contributes from 1 to 7 synapses per b1 cell throughout the on-alpha dendritic field. Here we use a compartmental model of an on-alpha cell, based on a reconstruction from electron micrographs of serial sections, to compute the contribution of the b1 array to the on-alpha receptive field. The computation shows that, for a physiologic range of specific membrane resistance (9500-68,000 omega.cm2) and a linear synapse, inputs are equally effective at all points on the on-alpha dendritic tree. This implies that the electrotonic properties of the dendritic tree contribute very little to the domed shapes of the receptive field center and surround. Rather, these shapes arise from the domed distribution of synapses across the on-alpha dendritic field. Various sources of "jitter" in the anatomical circuit, such as variation in bipolar cell spacing and fluctuations in the number of synapses per bipolar cell, are smoothed by the overall circuit design. However, the computed center retains some minor asymmetries and lumps, due to anatomical jitter, as found in actual alpha-cell receptive fields.  相似文献   
107.
目的:观察化瘀通络方治疗大鼠局灶性脑缺血-再灌注损伤对脑组织自由基及一氧化氮合成酶(NOS)和iNOS变化的影响。方法:制备大鼠局灶性脑缺血再灌注损伤模型,给予化瘀通络方治疗后观察丙二醛(MDA)、超氧化物歧化酶(SOD)及一氧化氮合成酶(NOS)和诱导型一氧化氮合成酶(iNOS)的变化。结果:化瘀通络方可显著降低MDA含量以及iNOS和NOS活性,SOD含量升高。结论:在脑缺血再灌注损伤后,化瘀通络方能抑制脑缺血再灌注后脂质过氧化反应,促进自由基清除,对抗自由基损伤,提高脑组织自身抗氧化能力,降低NOS和iNOS介导脑缺血-再灌注时的神经损伤,保护脑细胞。  相似文献   
108.
109.
OBJECTIVE: To determine the physician gender preferences of children and the consequences of meeting/not meeting children's preferences, both in their liking and feeling comfortable in talking with the pediatrician. METHODS: A convenience sample of 125 parent-child pairs completed surveys when coming for an outpatient visit to a university-sponsored, urban pediatric practice. RESULTS: Both adolescents and preadolescents (especially females) as young as 9 years of age expressed a gender preference for their physician. Meeting those preferences significantly affected how much children both liked and felt comfortable in talking with their physician. In young teen females, gender-preferred physicians are synonymous with gender-congruent physicians; yet although their preference for gender-congruent physicians increased in early adolescence, data indicated that their preference was often not met for several years to come. CONCLUSIONS: Liking and comfort with the pediatrician are not only desirable, but may also influence the doctor-patient relationship and young people's ability to develop health communication skills that they need as adults. These results, if validated, could also lead to a rethinking of parental dominance in the role of physician selection.  相似文献   
110.
To fully understand the preliminary stages of Taenia solium oncosphere attachment in the gut, adequate tools and assays are necessary to observe and quantify this event that leads to infection. A fluorescent-based quantitative adhesion assay, using biotinylated activated-oncospheres and monolayers of Chinese hamster ovary cells (CHO-K1) or human intestinal monolayer cells (INT-407, HCT-8 or HT-29), was developed to study initial events during the infection of target cells and to rapidly quantify the in vitro adhesion of T. solium oncospheres. Fluorescein streptavidin was used to identify biotinylated activated-oncospheres adhered to cells. This adherence was quantified using an automated fluorescence plate reader, and the results were expressed as fluorescence intensity values. A series of three assays were performed. The first was to identify the optimum number of biotinylated activated-oncospheres to be used in the adhesion assay. The goal of the second assay was to validate this novel method with the established oncosphere-binding system using the immunofluorescent-antibody assay (IFA) method to quantify oncosphere adhesion. A total of 10,000 biotinylated activated-oncospheres were utilized to assess the role of sera and laminin (LM) in oncosphere adherence to a CHO-K1 cell monolayer. The findings that sera and LM increase the adhesion of oncospheres to monolayer cells were similar to results that were previously obtained using the IFA method. The third assay compared the adherence of biotinylated activated-oncospheres to different types of human intestinal monolayer cells. In this case, the fluorescence intensity was greatest when using the INT-407 cell monolayer. We believe this new method of quantification offers the potential for rapid, large-scale screening to study and elucidate specific molecules and mechanisms involved in oncosphere-host cell attachment.  相似文献   
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