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31.
The current future understanding of inflammatory bowel disease   总被引:4,自引:0,他引:4  
Accumulating evidence indicates that the inflammatory bowel diseases result from an activation of immune and inflammatory responses initiated by a stimulation of the luminal flora or their products. Genetically determined variations in key mucosal functions, including cell activation by prototypic bacterial pattern molecules, lead to differential susceptibility to the development of these disorders, probably reflecting an interrelated activation of the innate and adaptive immune responses. The persistence and amplification of inflammation is likely to reflect the continuing presence of the driving stimulus and the complex, self-reinforcing activation of select T-helper subtypes and macrophages and other antigen-presenting cells, mediated by several cytokines. The latter include interleukins-2, 12, and 18 as well as interferon and macrophage migration inhibitory factors. The production of other broadly pro-inflammatory cytokines, most notably tumour necrosis factor and interleukins-1 and 6, enhances related inflammatory processes that eventually lead to many of the clinical manifestations of inflammatory bowel disease. The overall severity of the inflammatory process reflects a balance between leukocyte recruitment and downregulatory mucosal repair processes.  相似文献   
32.
33.

Background  

It has recently been shown that overexpression of the serine protease, matriptase, in transgenic mice causes a dramatically increased frequency of carcinoma formation. Overexpression of HAI-1 and matriptase together changed the frequency of carcinoma formation to normal. This suggests that the ratio of matriptase to HAI-1 influences the malignant progression. The aim of this study has been to determine the ratio of matriptase to HAI-1 mRNA expression in affected and normal tissue from individuals with colorectal cancer adenomas and carcinomas as well as in healthy individuals, in order to determine at which stages a dysregulated ratio of matriptase/HAI-1 mRNA is present during carcinogenesis.  相似文献   
34.
Background: General anaesthesia (GA) for cardiac magnetic resonance imaging (MRI) in patients with congenital heart disease (CHD) is challenging for the anaesthesiologist.  相似文献   
35.
Muscle sufficiency was significantly lower in 1336 children with chronic malnutrition of moderate to severe degree. Eighteen children with a chronic moderate degree of malnutrition and 8 well-nourished, age-matched controls were selected for biochemical and 31-phosphorus magnetic resonance spectroscopy (31 -P MRS) studies. The results showed that: (a) serum total protein, albumin, iron, calcium and inorganic phosphate were similar in both groups; (b) serum enzyme levels were significantly increased in the malnourished group; (c) 31-P MRS showed significantly higher means for total ATP, β-ATP, a-ATP and inorganic phosphate for the malnourished compared to the control group. In chronic malnutrition, proteins are maintained by degradation in muscle resulting in release of amino acids and enzymes. 31-P MRS studies showing increases in total ATP, β-ATP and inorganic phosphate and a decrease in phosphocreatine suggest that ATP is maintained at the cost of phosphocreatine.  相似文献   
36.
谭力  许丹科  刁勇  袁倚盛 《药学学报》1993,28(4):286-289
建立了人血浆洛美沙星的反相离子对高效液相色谱测定方法。该法简便易行,精密度好,方法回收率95~102%,日内、日间RSD为2.1~7.8%,血药浓度在0.125~5.012 μg/ml范围内呈线性关系,相关系数0.9998,当S/N=2时,最小检测浓度为25 ng/ml。健康志愿者口服400 mg洛美沙星,药代动力学过程符合一室模型,消除相半衰期为5.5 h。  相似文献   
37.
38.
For a brief period from the 1930s through the early 1940s, public health advocates made pneumonia a leading public health concern. Predicated on the need for antipneumococcal antiserum, but also incorporating physician reeducation, state "pneumonia control programs" were established nationwide. However, with the advent of penicillin and the sulfonamides, the pneumonia control programs soon collapsed. Pneumonia reverted to the domain of the private practitioner, which was devoid of state oversight. With the emergence of pneumococcal antibiotic resistance in the 1990s, the possibility again arose that pneumonia could become a public health concern, given the nationwide need to curb unnecessary antibiotic usage and to encourage vaccination. An understanding of the history of pneumonia's changing status could shed light on current attempts to reformulate the disease and elucidate the contested domains of private practice and public health.  相似文献   
39.

Background

The Rh blood system is one of the most polymorphic and immunogenic systems known to humans. The expression of Rh blood group antigen is complex. The Rh D antigen is the most important of the antigens that constitute the Rh antigen system. In most cases, D antigen can easily be detected. However, due to variability of expression, weak forms antigen are encountered. The reactivity of weak D with antisera is variable and presents as a problem in blood banking.

Methods

A retrospective analysis for a five-year period was done. Blood samples that were negative for Rh D by immediate spin tube method were tested for weak D antigen by additional lab tests.

Result

Of 34932 serial Rh grouping tests done in our Blood Bank, the incidence of weak D Rh antigen was 0.189%. All these were confirmed by the antiglobulin test.

Conclusion

These patients present as a problem for the blood banker and a curiosity to the clinician. Although uncommon, all health care workers should be aware of this entity to avoid anti D alloimmunisation.Key Words: Weak D, Rh Blood Group  相似文献   
40.
New life in a sleeper: thalidomide and Crohn's disease   总被引:1,自引:0,他引:1  
Sands BE  Podolsky DK 《Gastroenterology》1999,117(6):1485-1488
  相似文献   
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