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1.
Stomatococcus mucilaginosus was isolated from the blood of a patient with endocarditis and a past history of drug abuse and aortic valve replacement. At autopsy, Gram stain of the aortic valve revealed gram-positive cocci. Our isolate was atypical for S. mucilaginosus in that colonies were nonmucoid and nonadherent to agar surfaces. Cellular capsules were demonstrated by light and electron microscopy. Phenotypic characteristics identified by conventional methods as well as profile numbers obtained by using two commercial identification systems for staphylococci, the API Staph-Ident and the dms Staph Trac, are presented. Practical tests that differentiate S. mucilaginosus from the genera Micrococcus and Staphylococcus include growth on nutrient agar containing salt and lysostaphin susceptibility. Additional tests that helped differentiate our isolate from group D streptococci included hydrolysis of L-pyrrolidonyl-beta-naphthylamide and streptococcal serogrouping.  相似文献   
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The aromatic amine ortho-toluidine has been recognized by IARC as an animal carcinogen for the past decade. Three recent epidemiological studies of worker populations have now implicated this chemical as a human bladder carcinogen. In a study by E. Ward, A. Carpenter, S. Markowitz, D. Roberts, and W. Halperin ((1991), J. Natl. Cancer Inst. 83, 501–506), workers definitely exposed to ortho-toluidine for at least 10 years experienced a Standardized Incidence Ratio (SIR) of 27.2 (90% CI = 11.8–53.7). The other major exposure was to aniline, which significant epidemiological studies have failed to confirm as a human carcinogen. In retrospect, studies by G. F. Rubino, G. Scansetti, G. Piolatto ((1982) Environ. Res. 27, 241–254) and M. J. Stasik ((1988) Int. Arch. Occup. Environ. Health 60, 21–24) also support the hypothesis that ortho-toluidine is a human bladder carcinogen. Animal studies of both ortho-toluidine and its possible confounders in these epidemiological investigations further confirm this hypothesis. When evaluated in a suitably comprehensive way, according to the traditional standards for assessing causality outlined by A. B. Hill ((1977) A Short Textbook of Medical Statistics, pp. 288–294, Lippincott, Philadelphia) the evidence that ortho-toluidine causes human bladder cancer has become much more conclusive. In this case, animal tests have proven a good predictor of human carcinogenicity.  相似文献   
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报道了氯仿重结晶的棉酚的化学性质,样品在不同温度下干燥恒重后,经熔点、薄层层析、紫外光谱、红外光谱、X-射线衍射、热重量分析、元素(C,H,Cl)分析及棉酚合量测定等一系列的分析,确证了在60℃以下棉酚与氯仿成溶剂化物(solvate)。随着干燥温度的升高或在室温长时间的贮存,此现象逐渐消失,100℃真空干燥恒重后成为纯棉酚。  相似文献   
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The experience of the Charity Hospital surgeons in dealing with desmoid tumors is examined retrospectively over a 30-year period. Sixteen cases are presented. A 33 per cent rate of recurrence was noted despite excisions with margins free of tumor in each instance. In accordance with chi-square analysis, unequivocal statistical significance is given to the fact that women who have been pregnant are more likely to have abdominal than extraabdominal desmoid tumors. It was also found to be significant that parous women in whom desmoids develop are more likely to have the tumor within 10 years of their last pregnancy.  相似文献   
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The influence of family history on DNA repair synthesis, unscheduledDNA synthesis (UDS), was assessed in volunteers with or withouta family history of cancer. UDS, following treatment of mononuclearleukocytes with N-acetoxy-2-acetylaminofluorene, was measuredas the incorporation of [3H] into DNA in the presence of hydroxyurea.The positive family history group (n=71) had an average of 2.4first-degree relatives with cancer, defined as any major cancer,excluding skin cancer: 31 participants reported that canceroccurred in both their parents. The ‘no family history’comparison group (n=29) had no family history of cancer throughthe second degree. There was a significant reduction in UDSin cells from individuals with family history, compared to thosewith no family history (P>0.002). This relationship was notexplained by factors known to influence UDS, such as age, smokingor hypertension. We conclude that reduced UDS in mononuclearleukocytes is associated with a family history of any majorcancer, and is not confined to a history of cancer of any singleorgan site. This conclusion is further supported by the observationthat individuals (n=13) with parents who had an earlier onsetof cancer (<60 years) also had a significantly lower DNArepair synthesis than those (n=18) whose parents had later diagnosisof cancer (>60 years).  相似文献   
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OBJECTIVE--To describe the geographic distribution of measles cases in the United States by county for the 10-year period from 1980 through 1989. DESIGN--Ecological analysis of national measles surveillance data. METHODS--Measles cases reported to the Morbidity and Mortality Weekly Report from 1980 through 1989 were analyzed. Data from the 1980 and 1990 US censuses were used to produce demographic profiles for each of the 3137 countries. Outcome variables examined included mean annual incidence and number of years reporting measles, with use of Spearman's rank correlation coefficients to examine the association between the demographic and the two outcome variables. RESULTS--A total of 56,775 measles cases were reported during the decade. Of the nation's 3137 counties, 1690 (53.9%) did not report any cases; only 17 (0.5%) reported measles in all 10 years. Counties reporting measles more frequently during the decade had higher median populations, population densities, and percentage of black and Hispanic populations than those counties reporting less frequently. Population size, population density, and percentage of Hispanic population were associated with number of years reporting measles and mean annual measles incidence rate. Measles cases in counties reporting measles every year predominantly occurred in unvaccinated preschoolers; cases in counties reporting less frequently predominantly occurred in vaccinated school-aged children. CONCLUSIONS--This analysis illustrates the focal nature of measles in the United States during the past decade. Most counties have not reported a single case of measles during the entire decade, and only 17 counties reported measles every year. Targeted strategies are needed to improve age-appropriate immunization levels among preschool-aged children living in large inner-city areas.  相似文献   
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Siberian ginseng ([SG]; Eleutherococcus senticosus) is a commonly used herbal preparation. The objective of this study was to assess in normal volunteers (n = 12) the influence of a standardized SG extract on the activity of cytochrome P450 CYP2D6 and 3A4. Probe substrates dextromethorphan (CYP2D6 activity) and alprazolam (CYP3A4 activity) were administered orally at baseline and again following treatment with SG (1 x 485 mg twice daily) for 14 days. Urinary concentrations of dextromethorphan and dextorphan were quantified, and dextromethorphan metabolic ratios (DMRs) were determined at baseline and after SG treatment. Likewise, plasma samples were collected (0-60 h) for alprazolam pharmacokinetics at baseline and after SG treatment to assess effects on CYP3A4 activity. Validated high performance liquid chromatography methods were used to quantify all compounds and relevant metabolites. There were no statistically significant differences between pre- and post-SG treatment DMRs indicating a lack of effect on CYP2D6 (P > 0.05). For alprazolam there also were no significant differences in the pharmacokinetic parameters determined by noncompartmental modeling (C(max), T(max), area under the curve, half-life of elimination) indicating that SG does not significantly induce or inhibit CYP3A4 (P > 0.05). Our results indicate that standardized extracts of SG at generally recommended doses for over-the-counter use are unlikely to alter the disposition of coadministered medications primarily dependent on the CYP2D6 or CYP3A4 pathways for elimination.  相似文献   
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We describe a case of a full-term infant with severe respiratory failure and pulmonary insufficiency caused by an anomaly consisting of a single, unilobar lung arising from the trachea and situated in the middle mediastinum. Plain film, echocardiogram, and surgical aspects will be described and correlated with the post mortem findings and embryologic considerations. We were unable to find a similar case reported in the literature and conclude that this rare lesion represent an intermediate form between total and unilateral pulmonary agenesis. Presented at the Society for Pediatric Radiology, Washington D.C. 12 April 1986  相似文献   
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