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101.
Both the phytopathogenic fungus Ramularia collo-cygni and the hyperparasite R. uredinicola biosynthesize a number of red and yellow anthraquinone derivatives called rubellins. The new compounds uredinorubellins I and II, which were isolated from R. uredinicola, contribute to understanding the biosynthesis pathway that leads from simple anthraquinones to the rubellins. In addition, we isolated for the first time such simple compounds as chrysophanol and helminthsporin from both Ramularia species. A blue compound isolated from the mycelium of R. collo-cygni was revealed to be a unique 9,4-anthracenedione derivative. Structure elucidation by (1)H and (13)C NMR of the new but unstable compound caeruleoramularin was possible only by feeding the fungus different labeled (13)C acetates. The photodynamic activity of the uredinorubellins was comparable to rubellin D, whereas chrysophanol and caeruleoramularin did not display such activity.  相似文献   
102.
Abstract Weight gain during pregnancy is of great importance for the health of mother and child. There is considerable individual variability with regard to the weight gain, with maternal height and pre-pregnancy body weight being important determinants. We aim to assess the usefulness of the maternal body mass index (BMI) and other ways of combining maternal weight and height in predicting weight gain during pregnancy. We analyzed data of more than 2.2 million pregnancies taken from the German perinatal statistics of 1995-2000. We found that BMI is not useful as a predictor of weight gain during pregnancy. We developed an alternative system of using maternal weight and height to predict weight gain by classifying pregnant women according to their weight and height. This allows an assessment of weight gain by comparing a given pregnant woman to other women with similar weights and heights.  相似文献   
103.
OBJECTIVE: The pathogenesis of endometriosis is related to functional changes in CD3+ and CD14+ cells observed both at the local and systemic level. Here we investigated whether, and if so, how the body compartment influences cytokine expression in stimulated peritoneal and peripheral CD3+ and CD14+ cells of women with endometriosis. STUDY DESIGN: Isolated peripheral blood (PB) and peritoneal fluid (PF) mononuclear cells from women with endometriosis were cultured under non-adherent conditions and stimulated with PMA and ionomycin for 6h to induce intracellular cytokine synthesis of TNF-alpha, IFN-gamma, and IL-8 by CD3+ cells or with LPS for 9h to produce TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 by CD14+ cells. RESULTS: The percentages of positive CD3+ cells stained for TNF-alpha and IFN-gamma were significantly higher and those stained for IL-8 were significantly lower in PF compared with PB, this being independent of the stage of endometriosis. In contrast, the percentages of CD14+ cells producing TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 were significantly higher in PB than PF of women with endometriosis. CONCLUSIONS: Monocytes/macrophages and lymphocytes derived from the peripheral and peritoneal compartments of women with endometriosis differentially respond to stimulated cytokine synthesis induction. However, it is difficult to state whether the observed phenomenon is more related to body compartment influence per se or to the presence of endometriosis.  相似文献   
104.
OBJECTIVES: to confirm that fetal echocardiography is indeed possible in late first trimester and that it improves the standard of the so-called "genetic" ultrasound scan. MATERIAL AND METHODS: Early echocardiography was performed in 75 fetuses from high and low risk pregnancies. All fetuses underwent echocardiography examination in 18-22 weeks of gestation and established follow up. RESULTS: The most suitable method of visualization seems to be transabdominal examination, between 13.0-13.6 weeks of gestation, an transvaginal one, between 12.0-12.6 weeks of gestation, with 90% effectiveness. In researched group of 75 fetuses (with established follow up) there were four heart defects (5.3%). Three of them were diagnosed before 14th week of gestation. One case (tetralogy of Fallot) was overlooked. There were two false positive diagnosis verified at 20th week of gestation. CONCLUSIONS: Early echocardiography, especially between 12.0-13.6 weeks of gestation, is a possible and valuable method of diagnosis. Reference evaluation should be performed between 18 and 22 weeks of gestation. In cases with suspected anomalies karyotyping is recommended. Congenital heart disease diagnosed at late first trimester should be treated as the next potential marker of genetic disorder.  相似文献   
105.
OBJECTIVE: Well-known natural unspecific antimicrobial factors acting in the vagina are additionally reinforced during menstrual bleeding by hemocidins--a recently discovered novel class of microbicidal peptides generated proteolytically from hemoglobin. The aim of the presented research was to investigate the relation between the average length of menstrual bleeding and the frequency of urogenital infections. We expected that the shorter menstrual bleeding might increase the risk of urogenital infections because is synonymous with the shorter period of exposition on bactericidal action of hemocidins. STUDY DESIGN: The study contains statistical analysis of an average declared length of menstrual bleeding in the group of 267 young, sexually active women with the symptoms of urogenital infections. The control group consisted of 300 young healthy women. RESULTS: The length of menstrual bleeding in the group of patients with urogenital infections (average 4.35 days) was statistically significantly shorter than in the control group (average 4.95 days). The average length of the menstrual cycle was equal and counted ca. 28 days in both groups. CONCLUSION: The length of menstrual bleeding seems to be a significant factor in the vaginal ecology maintenance.  相似文献   
106.
When the administration of exogenous mineralocorticoid hormones was discontinued in adrenalectomized dogs maintained on glucocorticoid, net acid excretion decreased due largely to a reduction in urinary ammonium excretion (UNH4+V), and hyperchloremic hyperkalemic metabolic acidosis occurred and persisted. The reduction in UNH4+V was not associated with an increase in urine pH (UpH) or a decrease in urine flow, but correlated with the severity of hyperkalemia and was mitigated by dietary potassium restriction. UpH decreased to values as low as 5.3. During acidosis, UpH varied directly with UNH4+V, but in relation to UNH4+V, UpH exceeded that in acid-fed mineralocorticoid-replete dogs. Extrapolated to UNH4+V=0, however, UpH was not significantly different in the two groups (5.27 vs. 5.44). When distal delivery of sodium was increased by infusion of sodium phosphate, titratable acid excretion increased in both groups but pateaued at lower rates in the mineralocorticoid-deficient dogs. These results suggest that in mineralocorticoid-deficient dogs, renal ammonia production is diminished, in part due to potassium retention and hyperkalemia; renal hydrogen ion secretory capacity is reduced even when sodium and buffer delivery to the distal nephron is not reduced; and the ability of the kidney to generate normally steep urine-to-blood hydrogen ion concentration gradients is unimpaired.  相似文献   
107.
Nonrandomized studies of treatments from electronic healthcare databases are critical for producing the evidence necessary to making informed treatment decisions, but often rely on comparing rates of events observed in a small number of patients. In addition, studies constructed from electronic healthcare databases, for example, administrative claims data, often adjust for many, possibly hundreds, of potential confounders. Despite the importance of maximizing efficiency when there are many confounders and few observed outcome events, there has been relatively little research on the relative performance of different propensity score methods in this context. In this paper, we compare a wide variety of propensity‐based estimators of the marginal relative risk. In contrast to prior research that has focused on specific statistical methods in isolation of other analytic choices, we instead consider a method to be defined by the complete multistep process from propensity score modeling to final treatment effect estimation. Propensity score model estimation methods considered include ordinary logistic regression, Bayesian logistic regression, lasso, and boosted regression trees. Methods for utilizing the propensity score include pair matching, full matching, decile strata, fine strata, regression adjustment using one or two nonlinear splines, inverse propensity weighting, and matching weights. We evaluate methods via a ‘plasmode’ simulation study, which creates simulated datasets on the basis of a real cohort study of two treatments constructed from administrative claims data. Our results suggest that regression adjustment and matching weights, regardless of the propensity score model estimation method, provide lower bias and mean squared error in the context of rare binary outcomes. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
108.
ObjectiveTo predict future medical expenditures, health care utilization, and mortality in Switzerland using an updated chronic disease score (CDS), a chronic morbidity measure based on pharmacy data.Study Design and SettingWe performed a cohort study using medical claims data from insured persons enrolled in 2009 and 2010. Patient's characteristics, chronic conditions, and health care costs from baseline were used to calculate each patient's disease score. Two-part regression models were fit to predict health care expenditures, utilization, and mortality during the following year using the score's baseline values. We calculated the proportion of explained variation for each regression model to assess their performance.ResultsThe CDS model, controlled for sociodemographics and health insurance plan, showed a significant improvement in explained variance of health care costs, outpatient costs, and outpatient visits in 2010. Future outpatient visits were predicted best with an R2 of 29.2% (age group: 18–65 years) and 22.9% (>65 years), and models predicted future mortality with a c-statistic of 0.8.ConclusionThe CDS showed reasonable predictive validity of future health care utilization and medical expenditure based on pharmacy dispensing data, which may support health care decision makers in the planning delivery systems and resource allocation.  相似文献   
109.
This paper investigates if respondents' choice to not consider all characteristics of a multiattribute health service may represent preferences. Over the last decade, an increasing number of studies account for attribute non‐attendance (ANA) when using discrete choice experiments to elicit individuals' preferences. Most studies assume such behaviour is a heuristic and therefore uninformative. This assumption may result in misleading welfare estimates if ANA reflects preferences. This is the first paper to assess if ANA is a heuristic or genuine preference without relying on respondents' self‐stated motivation and the first study to explore this question within a health context. Based on findings from cognitive psychology, we expect that familiar respondents are less likely to use a decision heuristic to simplify choices than unfamiliar respondents. We employ a latent class model of discrete choice experiment data concerned with National Health Service managers' preferences for support services that assist with performance concerns. We present quantitative and qualitative evidence that in our study ANA mostly represents preferences. We also show that wrong assumptions about ANA result in inadequate welfare measures that can result in suboptimal policy advice. Future research should proceed with caution when assuming that ANA is a heuristic.  相似文献   
110.
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