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1.
功能性消化不良与幽门螺杆菌关系探讨   总被引:6,自引:0,他引:6  
功能性消化不良是一种人群中发病率很高的消化系统症状群,其发病机理未完全阐明,本文通过对2742例各类型功能性消化不良患者的胃粘膜的幽门螺杆菌感染情况作分析,发现动力障碍型HP阳性率65.3%,溃疡型HP阳性率74%,胃食管反流型HP阳性率24%,特发型HP阳性率21.4%,前两型与后两型的阳性率差异有显著性(P〈0.05),而前两型之间阳性率差异无显著性(P〉0.05),说明HP与动力障碍型和溃疡  相似文献   
2.
Sera of patients with ABPA were tested by XRIE tests incorporating their own serum (self-XRIE) to detect the presence of IgG/IgE antigen complexes to a “reference” Aspergillus fumigatus preparation. Of the 32 sera studied, 29 (90%) had visible precipitin (IgG) peaks, and 27 of these 29 as well as the three apparently precipitin-negative sera, i.e., 30 (94%), showed binding of specific IgE by autoradiography. The two precipitin-positive sera that did not show IgE binding were also skin test negative and RAST negative to this A. fumigatus antigen. Specific IgG as determined in ELISA correlated well with the grading of the XIE precipitin peaks (p < 0.05). There was also a highly significant correlation between specific IgE by RAST and grading the radioactive uptake seen in the autoradiograph (p < 0.001) indicating, for each serum, the presence of IgG antibodies to most of the components to which there was specific IgE. In the self-XRIE tests there was considerable variation of reactivity from serum to serum, in numbers of antigen/antibody peaks observed, in relative peak heights, and in the intensity of the respective staining. By comparing each test to a “reference” pattern developed with the use of an ABPA serum pool, the antigenic components of A. fumigatus were found to be of two main types: (1) antigens that appeared to be poorly precipitating (possibly low-molecular-weight components) but showed strong IgE binding (these were apparently major allergenic components and with one exception proved to be the faster migrating components) and (2) antigens that produced the strongest precipitin reactions with only weak binding of specific IgE and therefore minor allergenic components.  相似文献   
3.
Immunized rabbits that were aerosol challenged for 2 to 3 wk with pigeon dropping extract, an etiologic agent of hypersensitivity pneumonitis, developed chronic pulmonary inflammation associated with cell-mediated immunity in bronchoalveolar cells. However, prolonged aerosol challenge for 12 wk resulted in the diminution of pulmonary inflammation (modulation) and the loss of demonstrable cell-mediated immunity. This was probably not due to loss of sensitized lymphocytes that mediated pulmonary inflammation. Furthermore, rabbits undergoing modulation when they were challenged with an unrelated antigen were refractory to the development of pulmonary inflammation for at least 9 wk. After this refractory period, animals reimmunized and aerosol challenged with pigeon dropping extract displayed an anamnestic response and produced pulmonary lesions that were strikingly similar to the histopathology of human hypersensitivity pneumonitis.  相似文献   
4.
A portable device for the rapid concentration of viruses from natural freshwaters described and its performance in field use is evaluated. The system handled up to 500 litres of water in less than 90 min at a cost of only 2 pounds per sample. Where the samples contained sufficient bacteriophages for detection by direct plating the apparent phage recoveries were greater than 75%. Plant and animal viruses were also concentrated from waters with this system.  相似文献   
5.
6.
The 13C-triolein breath test is a method giving evidence of extent and rate of fatty acid oxidation in newborn infants on parenteral nutrition. The test has the special advantage of being non-invasive. Triolein labeled with the stable carbon isotope 13C and emulsified in soybean-oil is used as a tracer. 10 mg of 13C triolein per kg body weight are administered intravenously. The 13CO2 resulting from the fatty acid oxidation is analysed in expired breath by ratio-mass-spectrometry. The calculated 13C elimination is representative of the rate of fatty acid oxidation during the examination period. First studies on 15 premature infants have shown that an average of 27.0 +/- 1.8% of the dose administered is oxidized within 4 h. The present results suggest that the oxidation rate may be related to the maturity of the prematurely born infants.  相似文献   
7.
The accessibility of eukaryotic DNA is dependent upon the hierarchical level of chromatin organization. These include (1) intra-nucleosome interactions, (2) inter-nucleosome interactions and (3) the influence of non-histone chromatin architectural proteins. There appears to be interplay between all these levels, in that one level can override another or that two or more can act in concert. In the first level, the stability of the nucleosome itself is dependent on the number and type of contacts between the core histones and the surrounding DNA, as well as protein–protein interactions within the core histone octamer. Core histone variants, post-translational modifications of the histones, and linker histones binding to the DNA all influence the organization and stability of the nucleosome. When nucleosomes are placed end-to-end in linear chromatin arrays, the second level of organization is revealed. The amino terminal tails of the histone proteins make contacts with adjacent and distant nucleosomes, both within the fiber and between different fibers. The third level of organization is imposed upon these ‘intrinsic’ constraints, and is due to the influence of chromatin binding proteins that alter the architecture of the underlying fiber. These chromatin architectural proteins can, in some cases, bypass intrinsic constraints and impart their own topological affects, resulting in truly unique, supra-molecular assemblages that undoubtedly influence the accessibility of the underlying DNA. In this review we will provide a brief summary of what has been learned about the intrinsic dynamics of chromatin fibers, and survey the biology and architectural affects of the handful of chromatin architectural proteins that have been identified and characterized. These proteins are likely only a small subset of the architectural proteins encoded within the eukaryotic genome. We hope that an increased understanding and appreciation of the contribution of these proteins to genome accessibility will hasten the identification and characterization of more of these important regulatory factors.  相似文献   
8.
The expression of the nuclear protein Ki-67 (pKi-67) is strictly correlated with cell proliferation. Because of this, anti-Ki-67 antibodies can be used as operational markers to estimate the growth fraction of human neoplasia in situ. For a variety of tumours, the assessment of pKi-67 expression has repeatedly been proven to be of prognostic value for survival and tumour recurrence, but no cellular function has yet been ascribed to the Ki-67 protein. This study shows that a C-terminal domain of pKi-67 (Kon21) is able to bind to all three members of the mammalian heterochromatin protein 1 (HP1) family in vitro and in vivo. This interaction can be manipulated in living cells, as evidenced by ectopic expression of GFP-tagged HP1 proteins in HeLa cells, which results in a dramatic relocalization of endogenous pKi-67. Taken together, the data presented in this study suggest a role for pKi-67 in the control of higher-order chromatin structure.  相似文献   
9.
目的:探讨基层医院胃、十二指肠疾病幽门螺杆菌(HP)感染情况,检测方法及HP感染性胃病的临床病理形态特点。方法:采用北京同仁医院消化内科刘宾等提供的改良胃镜下HP感染的可视化诊断和Giemsa染色的HP形态学病理诊断方法,对203例上胃肠道疾病患者进行检测,并对其胃粘膜进行组织形态观察。结果:改良胃镜下HP的可视化诊断阳性率为96.55%,Giemsa染色病理诊断阳性率为95.07%,改良胃镜下HP感染的可视化诊断与病理诊断符合率为98.47%。HP感染胃粘膜有特征性组织形态改变。结论:改良胃镜下HP感染的可视化诊断及Giemsa染色HP形态学病理诊断相结合运用于胃、十二脂肠疾病的HP检测,适合普通基层医院采用。HP感染胃粘膜有特征性组织形态改变。  相似文献   
10.
目的 了解小儿上消化道疾病的发病情况和儿童胃病的HP感染情况。方法 对 180例小儿纤维胃镜检查分析及 172例胃粘膜HP检测及 16 8例胃、十二指肠粘膜病理检查结果进行总结。结果 疾病检出率为 93.3% ,其中以十二指肠炎、浅表性胃炎、消化性溃疡检出率最高 ;172例HP检测者中HP阳性 6 8例 ,阳性率为 37.8% ,其中以消化道溃疡检出率为最高 ,16 8例病理活检均为轻中度炎症。结论 HP感染在儿童慢性胃炎及消化道溃疡的致病中起重要作用 ,且随年龄增长而增加 ;儿童胃炎以轻、中度为主。  相似文献   
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