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61.
62.
Bacteria were isolated from 153 (47.5%) swabs of the appendix fossa in 322 patients undergoing appendicectomy. The commonest organism was Bacteroides species found in 78% of specimens. Other Gram-negative bacilli such as Klebsiella, or Enterobacter, and Esch. coli were present in 29 and 27% respectively. Gram-positive cocci were less frequently isolated.A positive culture was obtained more commonly in perforated appendicitis (79%) than where chronic fibrosis, lymphoid hyperplasia, or acute appendicitis was present or when the appendix was normal. Bacteroides was isolated twice as often in perforated appendicitis.The incidence of wound infection was 19% and varied according to the state of the appendix, being 63% in perforated appendicitis and 9.5% where lymphoid hyperplasia was present. Bacteroides was isolated from over 90% of the wound infections.In the patients with perforated appendicitis where effective chemotherapy was given the incidence of wound infection was 15% whereas in untreated or inappropriately treated patients it was over 50%.The isolation of bacteroides requires special precautions to be taken both in the collection of the specimen and laboratory culture. It is important that the chemotherapy of postappendicectomy infections include an antibiotic active against bacteroides.  相似文献   
63.
An intact Haemophilus ducreyi flp operon is essential for microcolony formation in vitro. tadA is the 9th of 15 genes in the operon and has homology to NTPases of type IV secretion systems. Fifteen human volunteers were experimentally infected with both H. ducreyi 35000HP and the tadA mutant, 35000HP.400. Papules developed at similar rates at sites inoculated with the mutant and parent, while pustules formed at 36.4% of parent sites and at 0% of mutant sites (P = 0.001). Compared to 35000HP, 35000HP.400 had only a modest but significant reduction in lesion scores in the temperature-dependent rabbit model of chancroid. These data suggest that proteins secreted by the flp locus are required for full expression of virulence by H. ducreyi in humans but have less of a role in virulence in an animal model of infection.  相似文献   
64.
Until now, no pathologic explanation could be found for the postoperative obstipation occurring in some patients with intestinal aganglionosis. Twenty-two of 108 infants treated for intestinal aganglionosis suffered from postoperative obstipation. Resected material from these 22 patients and from 17 control subjects was investigated with monoclonal anti-neurofilament antibody staining. An abnormal staining pattern was revealed in 18 of the constipated patients. Consequently, this new immunohistochemical staining technic has revealed a hitherto unsuspected cause for postoperative obstipation in aganglionosis. The monoclonal antibody may provide early warning of such postoperative constipation.  相似文献   
65.
IFN-gamma is a potent pro-inflammatory cytokine thought to be involved in the pathogenesis of Crohn's disease. To further define the role of IFN-gamma in intestinal inflammation, we studied the effects of intra-colonic 2,4,6-trinitrobenzene sulfonic acid (TNBS) instillation in mice with a functionally inactivated IFN-gamma receptor 1 (IFN-gammaR1(- / -)). Our results indicate that IFN-gamma is not necessary for the induction of hapten-induced colitis: after TNBS administration both wild-type and IFN-gammaR1(- / -) mice lost body weight, and the histological features of TNBS-induced colitis were comparable. Colons of IFN-gammaR1(- / -) mice contained a greater number of cells, represented by macrophages and CD4(+) T cells; caudal lymph node cells produced more IFN-gamma and TNF-alpha upon stimulation in vitro. Moreover, IL-18 and IL-12 p40 RNA levels were comparably up-regulated after TNBS treatment in IFN-gammaR1(- / -) wild-type mice. These findings demonstrate that IFN-gamma is dispensable for the development of TNBS-induced colitis. Importantly, the production of Th1 cytokines (e. g. IFN-gamma and TNF-alpha) by caudal lymph node T lymphocytes was enhanced rather than decreased in IFNgammaR1(- / -) mice with no evidence for default Th2 development.  相似文献   
66.
67.
Phenylketonuric and hyperphenylalaninaemic patients in the population of the Republic of Ireland were screened for mutations at the human phenylalanine hydroxylase (PAH) locus. A composite data set for the island of Ireland was generated by merging the findings of this study with extant data for Northern Ireland. Analysis of this data on the basis of the four historic provinces (Munster, Leinster, Connacht and Ulster) revealed genetic diversity that is informative in terms of demographic forces that shaped the Irish population. R408W, the predominant Irish PAH mutation associated with haplotype 1.8, reached its highest relative frequency in the most westerly province, Connacht. This suggests that the gradient of R408W-1.8 observed across north-western Europe continues into Ireland and peaks in Connacht. Spatial autocorrelation analysis demonstrated that the gradient is consistent with a localised cline of R408W-1.8 likely to have been established by human migration. This and parallel allele frequency clines may represent the genetic traces of the Palaeolithic colonisation of Europe, a pattern not substantially altered in north-western Europe by subsequent Neolithic migrations. An analysis of mutant allele distributions in Ulster, Scotland and the rest of Ireland confirmed that Ulster has been a zone of considerable admixture between the Irish and Scottish populations, indicating a proportion of Scottish admixture in Ulster approaching 46%. Mutations primarily associated with Scandinavia accounted for 6.1% of mutations overall, illustrating the influence of Viking incursions on Irish population history.  相似文献   
68.
69.
Alcohol use disorders in persons with co-occurring psychiatric disorders are associated with high rates of psy-chosocial instability and poorer treatment outcomes. Thus, assessment of alcohol use and abuse should become an integral part of psychiatric care. Because setf-report-based measures are frequently used, issues of reliability and validity in this population should be critically examined. The purpose of this article is to review and critique the existing empirical literature that has evaluated the psychometric integrity of self- report-based measures in psychiatric settings, and to outline a research agenda that promises to enhance the accuracy of alcohol assessment by persons receiving psychiatric treatment.  相似文献   
70.
Adenocarcinoma of the esophagus, or GEJ, has a poor prognosis. Early lesions [i.e. high grade dysplasia (HGD) or T1-carcinoma] are potentially curable. Local endoscopic therapies are promising treatment options for superficial lesions; however, for deeper lesions, surgical resection is considered to be the treatment of choice. To contribute to therapeutic decision-making, we retrospectively analysed the outcome of transhiatal esophagectomy in 120 patients with pathologically proven HGD (n=13) or T1-adenocarcinoma (n=107) of the distal esophagus or gastro-esophageal junction (GEJ). Tumors were subdivided into six different depths of invasion (T1-mucosal m1-m3, T1-submucosal sm1-sm3), and the frequency of lymphatic dissemination and time to locoregional and/or distant recurrence were analysed. Only one of the 79 T1m1-3/sm1 tumors (1%) showed lymph node metastases as compared with 18 out of 41 T1sm2-3 tumors (44%). There was a significant difference in recurrence-free period between T1m1-m3/sm1 versus T1sm2-sm3 tumor patients (P log rank <0.0001), with 5-year recurrence-free percentages of 97% and 57%, respectively. In multivariate analysis including age, gender, tumor differentiation grade, N-stage and depth of invasion, only N-stage was an independent prognostic factor for recurrence-free period (hazard rate=5.9, 95% CI 1.7–20.7). However, if N-stage was excluded from analysis, only depth of invasion (T1sm2-3 versus T1m1-m3/sm1) was an independent prognostic factor for recurrence-free period (hazard rate=7.5, 95% CI 2.0–27.7). These data indicate that T1m1-m3/sm1 adenocarcinomas of esophagus or GEJ show a very low risk of lymphatic dissemination and are therefore eligible for local endoscopic therapy. After transhiatal surgical resection, almost half of the patients with T1sm2-sm3 lesions develop recurrent disease within 5 years, and therefore need additional therapy to improve survival.  相似文献   
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