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To determine whether acetyl salicylic acid (ASA) in a daily dose of 1500 mg versus untreated controls is effective in patients with peripheral arterial disease a prospective randomized but not placebo-controlled one single centre trial was undertaken. Patients were assigned to one of two groups by means of multi-dimensional contingency tables whereas the risk factors age, sex, height, body weight, diabetic metabolic state, hypertension, history of myocardial infarction, smoking habits and preoperative clinical status according to the Fontaine classification where found in the state of balance. 298 patients with arterial occlusions in the iliaco-femoro-popliteal level were recruited during 1971-1974, the primary end points were probability of patency and probability of survival. In regard as well as to the probability of patency (p less than 0.56 Breslow, p less than 0.66 Mantel) as to the probability of survival (p less than 0.10 Breslow, p less than 0.70 Mantel) no statistical significant difference was detected. In conclusion ASA, in the doses administered here, was unable to improve patency or prolong patient survival, an outcome, which is at variance with results obtained by others.  相似文献   
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Appropriate follow-up of patients with needle core breast biopsies (NCBB) showing atypical hyperplasia remains unclear because previous studies show that subsequent open biopsies in variable proportions of these patients reveal ductal carcinoma in situ (DCIS) or even invasive carcinoma, indicating significant sampling artifact. NCBB with diagnoses of atypia were morphologically classified into groups as follows: I, ALH (n = 24); II, ADH with minimal cytologic atypism (n = 90); III, atypia, other (9 columnar, 2 apocrine, 11 atypical papillary); IV, severe ADH/borderline DCIS (n = 31). Mammographic and histologic features, including the number of foci of atypia in the NCBB and the calcification span, were then correlated with presence of DCIS or invasive tumor in subsequent open excisions. Open excisional biopsies showed more severe lesions in 12% of Group I-III cases (8% in Group I, 9% in Group II, and 27% in Group III), of which 15 were DCIS and one was an invasive tubular carcinoma (0.3 cm). Of the DCIS, 60% (n = 9) were < or =5 mm, and 13 of 15 (87%) were low grade. The NCBB cavity was immediately adjacent to the more severe lesions in 88% (n = 14) of cases, in keeping with sampling error. The subset showing severe ADH with borderline nuclear features in contrast was associated with a high likelihood (63%) of DCIS in follow-up excisions. NCBB with atypical papillary features also showed a high frequency of DCIS (4/11, 36%) in subsequent open excisions. Other factors associated with more severe lesions on open biopsy included the number of atypical foci in the NCBB (>4, P <.05) and the mammographic calcification span (>2.0 cm, P <.0001). Atypical lesions diagnosed in NCBB samples are radiographically and morphologically heterogeneous, accounting for the variable frequency of DCIS or invasive neoplasm identified in subsequent open excisions, which are usually focal, low grade, and a consequence of sampling artifact (i.e., adjacent to the NCBB cavity). DCIS is more likely if microcalcifications are mammographically extensive or if atypia is multifocal or is associated with borderline cytologic features.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Der Anteil älterer Personen in der Bevölkerung wächst stetig. Gleichzeitig steigen im Alter die Risiken für...  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Kommunale AkteurInnen erfahren bei der Entwicklung und Auswahl von Maßnahmen der Prävention und...  相似文献   
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BACKGROUND: Allele frequencies of single-nucleotide polymorphisms (SNPs) can be quantified from DNA pools. The conventional preparation of DNA pools requires DNA isolation and quantification for each blood sample. We hypothesized that pooling of whole blood samples according to their leukocyte count, which determines DNA content, would be as reliable as the conventional pooling method but much less tedious to perform. METHODS: We collected 100 whole blood samples and measured the leukocyte count. Samples were frozen until further use. After thawing, pools were generated by combining aliquots containing an equal number of leukocytes. In parallel, DNA was extracted from another aliquot, DNA concentration was measured, and DNA concentration-based pools were assembled. All original samples were genotyped directly using 4 different SNP assays to obtain the exact allele frequencies in the pool. In addition, samples of known genotypes were mixed according to the DNA concentration or the leukocyte count to generate artificial samples of known allele frequencies. We analyzed pools and mixes in triplicate by pyrosequencing and calculated allelic frequencies. RESULTS: Leukocyte and DNA pooling provided equally accurate and precise SNP frequencies comparable to published data. CONCLUSION: DNA and leukocyte pooling are both suitable strategies to determine allele frequencies in frozen samples. The leukocyte pooling approach is much less tedious, quicker, and less expensive. It should be always considered if leukocyte counts are available.  相似文献   
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Organisms live in continuos interaction with their environment; this interaction is of vital importance but at the same time can be life threatening. The largest and most important interface between the organism and its environment is represented by surfaces covered with epithelial cells. Of these surfaces, mucosae comprise in humans approximately 300 m2, and the skin covers approximately 1.8 m2 surface of the human body. Mucosal tissues contain two effector arms of the immune system, innate and adaptive, which operate in synergy. Interaction with commensal bacteria, which outnumber the nucleated cells of our body, occurs physiologically on epithelial surfaces; this interaction could pose the risk of inflammation. The mucosal immune system has developed a complex network of regulatory signalling cascades that is a prerequisite for proper activation but also for a timely inactivation of the pathway. As demonstrated in gnotobiotic animal models of human diseases, impaired regulation of mucosal responses to commensal bacteria plays an important role in the development of several inflammatory and autoimmune diseases.  相似文献   
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