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Extensive studies in rodents suggest that serotonin (5-HT) modulates nociceptive responses through the stimulation of several receptor types. However, it remains to demonstrate that these receptors participate in the control of nociception under physiological conditions. Pain behaviors of mutants which do not express 5-HT1A, 5-HT1B, 5-HT2A or 5-HT3A receptors, or lacking the 5-HT transporter, compared to paired wild-type mice of the same genetic background, were examined using validated tests based on different sensory modalities. Mechanical (von Frey filaments, tail pressure, tail clip tests), thermal (radiant heat, 46 °C water bath, hot-plate test) and formalin-induced nociception were determined in 2- to 3-month-old males. 5-HT1A knock-out mice differed from wild-types by higher thermal sensitivity (hot-plate test only), and 5-HT1B knock-out mice by higher thermal and formalin sensitivity. Both 5-HT2A and 5-HT3A knock-out mice differed from wild-types by a dramatic decrease in the formalin-induced nociceptive responses for phase II (16–45 min after injection/inflammatory phase). In contrast, neither mechanical, thermal nor formalin-induced nociception differed between mutants lacking the 5-HT transporter and paired wild-type mice. Although differences in spontaneous locomotor activity in 5-HT1B−/− (increase) and 5-HT3A−/− (decrease) knock-out mice versus paired wild-types might have confounded differences in nociception, acute 5-HT receptor blockade by selective antagonists was found to replicate in wild-type mice the effects on pain behavior, but not on locomotor activity, of the respective gene knock-out in mutants. These results support the conclusion that the complex control of pain mechanisms by 5-HT, acting at multiple receptors, is physiologically relevant in mice.  相似文献   
63.
Sixty isolates of Enterobacteriaceae resistant to beta-lactam antibiotics were collected over a period of 2 years in Switzerland and screened by hybridization for the carriage of SHV genes. Thirty-four positive strains were found, and their SHV genes were amplified and sequenced. SHV extended-spectrum beta-lactamases (ESBLs) were found: 13 strains contained SHV-2a, 12 harbored SHV-2, and SHV-5 was found twice. Four strains were shown to contain SHV-1. In addition, we report two new SHV variants, termed SHV-11 (non-ESBL) and SHV-12 (ESBL). In spite of the carriage of SHV ESBLs, many strains showed only low resistance to one or more third-generation cephalosporins. In addition, 26 did not transfer the blaSHV gene in mating experiments.  相似文献   
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Summary Two patients, suffering from AML and AMMoL respectively, experienced acute GVHD after transfusion of nonirradiated blood products. One of the patients, who surprisingly showed normal granulocyte counts during the acute phase of GVHD, survived and is disease-free eight months after initial diagnosis was made.Vorgetragen auf der Sitzung Aktuelle Mitteilungen der 26. Jahrestagung der Deutschen und Österreichischen Gesellschaft für Hämatologie und Onkologie im Oktober 1981 in München  相似文献   
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Summary The incidences of the cancer of the oesophagus, stomach, small intestines, colon, and rectum for the years 1971–1977 in the regional district of North Baden, Federal Republic of Germany are presented and their relation to environmental factors are discussed briefly. The age specific incidence as well as the age standardized incidence and the sex ratios show remarkable differences due to the specific tumor localizations. The colon cancer incidence in the female population increases steeply during the period considered. The risk of developing rectal cancer also increases. The results of the pathoanatomic registry are well comparable with the data from clinical registries.Supported by the DFG (SFB 136)  相似文献   
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Trichinella infection and clinical disease   总被引:1,自引:0,他引:1  
Trichinellosis is caused by ingestion of insufficiently cooked meat contaminated with infective larvae of <it>Trichinella</it> species. The clinical course is highly variable, ranging from no apparent infection to severe and even fatal disease. We report two illustrative cases of trichinellosis. Returning to Denmark a few days after having eaten roasted pork in the Republic of Serbia, a female patient suffered from severe vomiting, epigastric pain, diarrhoea, and later myalgia, generalized oedema, and prostration. A biopsy showed heavy infestation with <it>Trichinella spiralis</it>, 2000 larvae/g of muscle. Life-threatening cardiopulmonary, renal and central nervous system complications developed. The patient recovered after several months. Her husband, who also ate the pork, did not have clinical symptoms, but an increased eosinophil count and a single larva in a muscle biopsy confirmed infection. The epidemiology, clinical manifestations, diagnosis, treatment and prevention of trichinellosis are reviewed.   相似文献   
70.
The intracardiac injection model is a commonly used in vivo model to test therapeutic response in bone metastases. However, few studies have critically compared the performance of different imaging methods in terms of sensitivity and quantitative assessment of osteolytic lesions. We performed in vivo optical and plain radiographic imaging of bone metastases followed by high-sensitivity ex vivo micro-computed tomography (micro-CT) imaging. This approach allowed for quantitative assessment of in vivo imaging techniques using fluorescence and plain radiography. Comparison of lesions detected in vivo by fluorescent optical imaging with ex vivo micro-CT revealed that the limited spatial resolution of fluorescent optical imaging may underestimate the number of bone metastases. Radiography was compared with micro-CT for the detection of osteolytic lesions. When using dichotomous yes/no grading, there was a 64% agreement in detection of osteolytic lesions. When subjective semiquantitative grading methods were used to assess the extent of osteolytic lesions, a positive association between the micro-CT grades and the square root of the radiography-based grades was observed (p < 0.05). Micro-CT also showed a significant association with fluorescent optical values; however, no such association was observed between lesion scores based on radiographs and those based on fluorescent imaging. The findings reveal an approximate two-fold sensitivity for micro-CT compared to plain radiography in the detection of osteolytic lesions. Significant associations between micro-CT-based osteolytic lesion grade and tumor growth characterized by increased fluorescent area document the value of these two techniques for the assessment of osteolytic bone metastases.  相似文献   
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