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101.
Chicken carcasses from a supermarket and from a poultry abattoir were examined using methods designed to isolate as many strains of campylobacters and related organisms as possible. Strains of arcobacter, but no campylobacters, were isolated from every carcass after enrichment. Campylobacter jejuni subsp. jejuni was isolated from all carcasses examined by direct plating and other Campylobacter-like strains were isolated from nine out of 15 abattoir carcasses by direct plating but not after enrichment. Only the Camp. jejuni subsp. jejuni strains could be identified to species level using a readily available identification scheme and/or a commercial identification kit. Examination of caecal contents from the 15 abattoir poultry yielded Camp. jejuni subsp. jejuni and Campylobacter-like strains from 15 and eight by direct plating, and from six and nine after enrichment, respectively. Four sites in the intestine of the abattoir birds (60 samples) were examined for arcobacters and only one strain was isolated. This indicates that arcobacters are probably not normal inhabitants of the poultry intestine. Poultry is a rich source of other campylobacteria besides the thermophilic Campylobacter spp. 相似文献
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We describe three case reports of hematomas in the abdominal wall muscles and discuss etiology, diagnostic findings and treatment. Abdominal wall hematomas are uncommon, and the condition is often misdiagnosed. One of our patients was laparotomised owing to suspected appendicitis, and one patient presented a tuberculous abscess that may have been an infected hematoma. Ultrasonographic examination or CT gives the correct diagnose. Conservative management is the treatment of choice unless bleeding is severe or the course is complicated by infection. 相似文献
109.
The extracellular environment controls many cellular activities thereby linking external material cues to internal cell function. By better understanding these processes, synthetic extracellular material niches can be tailored to present cells with highly regulated physical and/or chemical cues that promote or suppress selected cell functions. Here, poly(ethylene glycol) (PEG) hydrogels were functionalized with fluvastatin-releasing grafts and growth factor binding heparin domains to enable the dynamic exchange of information between the material and cells from the outside-in and inside-out (i.e., bidirectional signaling). By incorporating a fluvastatin-releasing graft and carefully controlling the dose and temporal release, materials were designed to promote bone morphogenic protein (BMP2) and alkaline phosphatase (ALP) production by human mesenchymal stem cells (hMSCs). When the release of fluvastatin was controlled to occur over 2 weeks, BMP2 and ALP production was increased 2.2-fold and 1.7-fold, respectively, at day 28 compared to hMSCs cultured in the absence of fluvastatin. By introducing a heparin functionality into the gel to sequester and localize the hMSC-produced BMP2, the osteogenic differentiation of hMSCs was further augmented over fluvastatin delivery alone. Osteopontin and core binding factor α1 gene expression was 6-fold and 4-fold greater for hMSCs exposed to fluvastatin in the presence of the heparin functionalities, respectively. These results demonstrate how multifunctional gels that interact with cells in a bidirectional manner can efficiently promote selected cell functions, such as the osteogenic differentiation of hMSCs. 相似文献
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KW Mahaffey CB Granger R Collins CM O'Connor EM Ohman SD Bleich JJ Col RM Califf 《Canadian Metallurgical Quarterly》1996,77(8):551-556
Intravenous heparin is routinely given after thrombolytic therapy for patients with acute myocardial infarction in the United States and in some, but by no means all, other countries. Several trials have documented improved infarct-artery patency in patients treated with heparin; however, none was large enough individually to assess the effect of heparin on clinical outcomes. We performed a systematic overview of the 6 randomized controlled trials (1,735 patients) to summarize the available data concerning the risks and benefits of intravenous heparin versus no heparin after thrombolytic therapy. Mortality before hospital discharge was 5.1% for patients allocated to intravenous heparin compared with 5.6% for controls (relative risk reduction of 9%, odds ratio 0.91, 95% confidence interval 0.59 to 1.39). Similar rates of recurrent ischemia and reinfarction were observed among those allocated to heparin therapy or control. The rates of total stroke, intracranial hemorrhage, and severe bleeding were similar in patients allocated to heparin; however, the risk of any severity of bleeding was significantly higher (22.7% vs 16.2%; odds ratio 1.55, 95% confidence interval 1.21 to 1.98). There was no significant difference in the observed effects of heparin between patients receiving tissue-type plasminogen activator and those receiving streptokinase or anisoylated plasminogen streptokinase activator complex, or between patients who did and did not receive aspirin. The findings of this overview demonstrate that insufficient clinical outcome data are available to support or to refute the routine use of intravenous heparin therapy after thrombolysis. It is not known if these findings are due to lack of statistical power, inappropriate levels of anticoagulation, or lack of benefit of intravenous heparin. Large randomized studies of heparin (and of new antithrombotic regimens) are needed to establish the role of such therapy. 相似文献