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91.
The silver(i) and iodine(i) complexes of the 2-substituted pyridines 2-(diphenylmethyl)pyridine (1) and 2-(1,1-diphenylethyl)pyridine (2), along with their potential protonated side products, were synthesised to investigate the steric limitations of iodine(i) complex formation. The complexes were characterised by 1H and 1H–15N HMBC NMR, X-ray crystallography, and DFT calculations. The solid-state structures for the silver(i) and iodine(i) complexes were extensively compared to the literature and analysed by DFT to examine the influence of the sterically bulky pyridines and their anions.

The silver(i) and iodine(i) complexes of two sterically bulky 2-substituted pyridines, along with their potential protonated side products, were synthesised to investigate the steric limitations of iodine(i) ion formation.  相似文献   
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PURPOSE: Aortic aneurysms have a high fatality rate that could be reduced with control of risk factors and use of available screening methods for detection of early changes in aortic walls. The available data on familial risks, a potential indication for screening, are mainly limited to abdominal aortic aneurysms. METHODS: A nationwide Swedish cohort was constructed by linking the Multigeneration Register on 0- to 69-year-old siblings to the Hospital Discharge Register and the Cause of Death Register for data on aortic aneurysms from years 1987 to 2001. Standardized incidence ratios (SIRs) were calculated for affected siblings by comparing with those whose siblings had no aneurysm. RESULTS: A total of 71 affected siblings were identified with a familial SIR of 8.71; when one sibling was diagnosed before age 50 years, the SIR was 19.69. For concordant thoracic or concordant abdominal aneurysms, the SIRs were 21.68 and 13.06, respectively. For brothers, the risk of abdominal aneurysms was 14.63, and 49.50 for diagnosis before age 50 years. Familial risks and the effects of early diagnostic age were shared by the anatomic subtypes of aneurysms. Within limits of the sample size, no gender differences could be observed. Affected siblings constituted 2.2% of all diagnosed patients. CONCLUSIONS: A family history of any aortic aneurysms and age groups younger than 50 years should be considered in recommendations for screening. The high familial risks are likely to be the result of heritable genes, the identification of which would allow gene testing and preventive counseling.  相似文献   
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We studied the origin of transferrin receptor (CD71) positive cells in blood from seven women pregnant with a male fetus in order to explore if fetal cells could be detected among them. We used a technique that allows direct chromosomal analysis by in situ hybridization on immunologically and morphologically classified cells. Enrichment was performed by magnetic activated cell sorting (miniMACS)® using an anti-CD71 monoclonal antibody. The cells were immunophenotyped by alkaline phosphatase anti-alkaline phosphatase immunostaining with the same antibody. The origin of the immunophenotyped cells was studied by in situ hybridization using an X cosmid Y repeat chromosome specific probe cocktail. CD71 positive cells were found in six of the seven women at the range of 4 to 43 in respective samples. Over 90% of the CD71 positive cells were nucleated erythrocytes. None of the detected positive cells were shown to be fetal. Thus, the use of transferrin receptor antigen alone in combination with the miniMACS® may not be sufficient for enrichment of fetal cells.  相似文献   
95.
We explored sex ratio at birth, defined as the proportion of male live births, in women with anorexia nervosa, bulimia nervosa, binge eating disorder, and eating disorders not otherwise specified-purging type (EDNOS-P) relative to a referent group in a large population-based sample of 38,340 pregnant women in Norway. Poisson regressions were adjusted for mother's age, pre-pregnancy BMI, lifetime smoking status, maternal education, income, marital status, gestational age, and parity. Lower proportions of male live births were observed in the anorexia and bulimia groups, while binge eating disorder and EDNOS-P were associated with a higher proportion of male births. These data suggest that maternal eating disorders may influence offspring sex and that the direction of effect may vary by eating disorder subtype. If confirmed, this finding could provide evidence in formulating hypotheses regarding the consequences of eating disorders and determinants of sex ratio at birth.  相似文献   
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Background: Colorectal adenomas are the usual precursors to carcinoma in sporadic and hereditary colorectal cancers (CRC).Methods: A total of 220 CRC patients (stages 0, I, and II) were randomized prospectively in a double-blind pilot study of calcium chemoprevention by using recurrent colorectal adenomas as a surrogate end point. This trial is still in progress, and we report the preliminary findings on adenoma recurrence rates.Results: Synchronous adenomas were present in 60% of patients, and cancer confined in a polyp was present in 23% of patients. The overall cumulative adenoma recurrence rate was 31% (19% in the first year, 29% for 2 years, and 35% for 3 years). The recurrence rates were greater for patients with synchronous adenomas: 38% at 3 years (P = .01). Lower stage was associated with higher adenoma recurrence rates (P = .04). Factors including age, sex, site of primary cancer, and whether the cancer was confined to a polyp were not significantly associated with differences in adenoma recurrence rates.Conclusions: The substantial adenoma recurrence rate in patients resected of CRC justifies colonoscopic surveillance on a periodic basis. Patients with higher rates of adenoma recurrences, such as CRC with synchronous adenomas, are ideal subjects for chemoprevention trials.  相似文献   
99.
Subendothelial mast cells have been implicated in the pathogenesis of allergic inflammation, in atherosclerosis, and in the regulation of vascular tone. Because endothelin-1 (ET-1) is an important regulator of vascular tone and has also been implicated in the pathogenesis of atherosclerosis, we studied the role of mast cells in the metabolism of endothelial cell-derived ET-1. In mast cell-endothelial cell cocultures, activation of the mast cells with ensuing degranulation was accompanied by the increased expression of ET-1 mRNA in the endothelial cells, yet the immunoreactive ET-1 protein in the coculture medium disappeared almost completely during the 24-hour coculture. Activation of the mast cells with the ensuing degranulation resulted in proteolytic degradation of ET-1 by the 2 neutral proteases, chymase and carboxypeptidase A, of the exocytosed mast cell granules. With synthetic ET-1 and purified mast cell granule enzymes, efficient degradation of ET-1 by chymase and carboxypeptidase A was verified. These in vitro results imply a novel role for mast cell-derived neutral proteases in ET-1 metabolism and suggest that activated subendothelial mast cells are important local regulators of ET-1 metabolism.  相似文献   
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