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排序方式: 共有793条查询结果,搜索用时 15 毫秒
41.
Perkonigg A Yonkers KA Pfister H Lieb R Wittchen HU 《The Journal of clinical psychiatry》2004,65(10):1314-1322
BACKGROUND: There is some evidence that the onset and course of premenstrual syndrome is related to stress; however, few studies have explored the role of traumatic events and post-traumatic stress disorder (PTSD) as risk factors for the development of premenstrual dysphoric disorder (PMDD). METHOD: A community cohort of 1488 women (aged 14-24 years at baseline) were prospectively and longitudinally evaluated up to 3 times over a period of about 42 months from 1995 to 1999. The DSM-IV version of the Munich-Composite International Diagnostic Interview was used to establish PMDD and PTSD diagnostic status; stressful life events and conditions were assessed with the Munich Events List and the Daily Hassles Scale. Prevalence and incidence of either threshold or subthreshold PMDD from baseline to the second follow-up were calculated. Risk factors, including prior comorbid mental disorders and traumatic events, were examined using logistic regression analysis. RESULTS: The incidence of threshold PMDD was 3.0%. The most powerful predictors were subthreshold PMDD at baseline (OR = 11.0, 95% CI = 4.7 to 25.9). Traumatic events greatly increased the odds of developing PMDD at follow-up (OR = 4.2, 95% CI = 1.2 to 12.0). Other predictors were a history of anxiety disorder (OR = 2.5, 95% CI = 1.1 to 5.5) and elevated daily hassles scores (OR = 1.6, 95% CI = 1.1 to 2.3). Both were also associated with the risk of developing subthreshold PMDD, although the association was less robust. CONCLUSIONS: Traumatic events and pre-existing anxiety disorders are risk factors for the development of PMDD. The underlying mechanisms are unknown, making further investigation necessary. 相似文献
42.
Data from Berlin (Germany) show a significant correlation between the increase in the stork population around the city and the increase in deliveries outside city hospitals (out-of-hospital deliveries). However, there is no correlation between deliveries in hospital buildings (clinical deliveries) and the stork population. The decline in the number of pairs of storks in the German state of Lower Saxony between 1970 and 1985 correlated with the decrease of deliveries in that area. The nearly constant number of deliveries from 1985 to 1995 was associated with an unchanged stork population (no statistical significance). However, the relevance of the stork for the birth rate in that part of Germany remains unclear, because the number of out-of-hospital deliveries in this area is not well documented. A lack of statistical information on out-of-hospital deliveries in general is a severe handicap for further proof for the Theory of the Stork. 相似文献
43.
Lung cancer continues to be the leading cause of cancer death in industrialized countries and there is an urgent need for the development of preventive treatments that inhibit the progression of initiated cells into overt lung cancer in smokers who quit. Murine pulmonary adenocarcinoma models are widely used to test prospective cancer preventive agents. These tumors are of alveolar type II cell lineage, express growth-regulating signal transduction pathways that are stimulated by epidermal growth factor and protein kinase C while being inhibited by agents that increase intracellular cyclic AMP (cAMP). By contrast, pulmonary adenocarcinomas induced in hamsters are derived from bronchial and bronchiolar Clara cells, are under beta-adrenergic receptor control and their development is promoted by agents that increase intracellular cAMP. Adenocarcinomas of either cell lineage develop in humans, raising the possibility that agents with strong chemopreventive activity in murine lung cancer models due to stimulation of cAMP may selectively promote human pulmonary adenocarcinomas derived from Clara cells. We therefore compared the effects of the beta-adrenergic agonist isoproterenol and the activator of cAMP forskolin under controlled in vitro conditions on the human pulmonary adenocarcinoma cell line NCI-H322 which expresses a Clara cell phenotype versus the human pulmonary adenocarcinoma cell line A549 which expresses features of alveolar type II cells. Our data show that isoproterenol significantly stimulated cAMP, ERK1/2 activity and DNA synthesis in NCI-H322 cells and that this response involved transactivation of the EGF receptor. By contrast, we found that isoproterenol had no effect on A549 cells whereas forskolin significantly inhibited DNA synthesis and ERK1/2 activity. Our findings are consistent with the interpretation that human pulmonary adenocarcinomas of Clara cell lineage are highly sensitive to the cancer promoting effects of beta-adrenergic agonists and other agents that stimulate cAMP whereas human cancers of the same histological family but derived from alveolar type II cells are resistant to beta-adrenergic agonists and respond with a reduction in cell growth to stimulation of cAMP. Our findings suggest that some widely advertised cancer preventive agents such as green tea, retinoids and beta-carotenes are unsafe to be used by smokers or by ex-smokers due to their tumor promoting effects via stimulation of cAMP on initiated cells of Clara cell lineage. 相似文献
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The International Reflux Study in Children was set up to compare prospectively the outcome of medical or surgical management of children with grade III or IV vesicoureteral reflux and a history of symptomatic urinary tract infection. Development of new radiological scars was the main end point. Of the 306 children randomized, 302 (153 medical, 149 surgical) were available for radiological follow-up at 5 years. New scars had developed in 19 medically and 21 surgically treated children. Among 223 patients (113 medical, 110 surgical) who continued follow-up with urography at 10 years, only 2 further new scars developed. Overall, 47 new scars were acquired in 42 patients (20 medical, 22 surgical), 25 of them in children with unscarred kidneys at entry (13 medical, 12 surgical). New scars occurred mostly in children under 5 years of age and were observed more frequently in children with grade IV than grade III reflux. We conclude that with careful management, only a small proportion of children with severe reflux developed new scars and rarely after the first 5-year follow up period, and that there was no difference between children treated medically or surgically.The authors are the writing committee of the European arm of the International Reflux Study in Children. H. Olbing is deceased. Co-ordinating center, Essen, Germany: chairman H. Olbing, scientific co-ordinator T. Tamminen-Möbius, statistics H. Hirche, documentation H. Lax. Participating university hospitals and investigators: Bonn, Germany: R. Mallmann, D. Emons; Brussels, Belgium: M. Hall, A. Piepsz, C. Schulmann; Essen, Germany: H.J. Bachmann, W. Rascher, E. Brunier, C. Reiners, J. Behrendt, P. Mellin (deceased); Gothenburg, Sweden: U. Jodal, K. Hjälmås, E. Hanson, N. Nilsson, J. Bjure (deceased), R. Sixt; Hamburg, Germany: R. Busch, C. Montz; Helsinki, Finland: O. Koskimies, S. Wikström, E. Marttinen, A. Kivisaari, T. Korppi-Tommola; Oulu, Finland: J. Seppänen (deceased), N.P. Huttunen, U. Seppänen, J. Heikkilä; Stockholm, Sweden: A. Aperia, G. Löhr, P. Herin, U. Freyschuss, L. Blom, U. Erasmi, B. Söderborg. Consultants: I. Claesson, K.-D. Ebel, R.A. Lebowitz, K. Parkkulainen, J.M. Smellie, I. Wikstad, and J. Winberg (deceased) 相似文献
47.
Mittag O Böhmer S Deck R Ekkernkamp M Hüppe A Telbis-Kankainen H Raspe A Raspe H 《Sozial- und Pr?ventivmedizin》2003,48(1):55-64
OBJECTIVES: Traditional pretests are used in the development of survey items to identify technical and comprehension problems. Cognitive processes involved in answering survey questions are not the object of this kind of test. METHODS: Cognitive survey methods were used here to test a questionnaire screening for rehabilitation needs in people suffering from back pain. Essential techniques of cognitive testing (think-aloud, probing, confidence ratings) are outlined. We applied these techniques to 20 patients suffering from either acute or chronic back pain in order to test the survey. RESULTS: The main goal, i.e., identifying problems in item formulation by means of cognitive testing, was achieved. Almost one third of the survey questions were rephrased according to the results of the study. Some of the improvements of the questionnaire are illustrated. CONCLUSIONS: The increased effort required to perform cognitive testing as compared to traditional pretesting pays off. The two methods have specific pros and cons and cannot replace one another. 相似文献
48.
U. Wendel K. Becker Hildegard Przyrembel Monika Bulla C. Manegold Angelika Mench-Hoinowski U. Langenbeck 《European journal of pediatrics》1980,134(1):57-63
We report biochemical data on a child with MSUD who underwent peritoneal dialysis for severe metabolic imbalance. In confirmation of earlier data, the BCKA/BCAA ratios in blood had been found to be fairly stable in this patient during long-term dietary therapy.The child became comatose at comparatively low levels of leucine and KICA (ca. 2 mM each). At this time the blood/cerebrospinal fluid ratio for BCAA's and BCKA's was markedly diminished. During peritoneal dialysis, peritoneal clearance was highest for KIVA, but less for MEVA and BCAA's (40–50% or urea clearance), and least for the allegedly most toxic metabolite, KICA. The differences for BCKA's may be due to their differential protein binding. Given these individual differences, 1.8 to 8.7 initial plasma volumes were cleared in 14h with 24.21 of dialysis fluid. In the same time, urinary excretion of BCAA's and BCKA's was much less efficient.The data are discussed with regard to the pathobiochemical significance of high tissue levels of branched chain acids. A quantitative comparison between peritoneal dialysis and exchange transfusion is not yet possible.Abbreviations
BCAA's
branched-chain -amino acids
-
BCKA's
branched-chain -keto acids
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KICA
-keto-isocaproic acid
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KIVA
-keto-isovalerio acid
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MEVA
-keto--methyl-n-valeric acid
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MSUD
maple syrup urine disease
With support of the Landesamt für Forschung des Ministeriums für Wissenschaft und Forschung des Landes Nordrhein-Westfalen. U.L. was supported by Deutsche Forschungsgemeinschaft, Bad Godesberg, G.F.R. (DFG La 201, Schwerpunkt Biochemische Humangenetik and SFB 33 Nervensystem und biologische Information) 相似文献
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Hilgendorf I Freund M Jilg W Einsele H Gea-Banacloche J Greinix H Halter J Lawitschka A Wolff D Meisel R 《Vaccine》2011,29(16):2825-2833
Patients lose protective immunity to vaccine-preventable diseases after haematopoietic stem cell transplantation (HSCT). Therefore, revaccination of HSCT recipients represents an important strategy for reducing morbidity and mortality associated with these infections. Since there is little consensus on vaccine recommendations and practices for allogeneic HSCT recipients with active chronic graft-versus-host disease (GVHD) the German-Austrian-Swiss-Consensus Conference on Clinical Practice in Chronic GVHD developed an immunization schedule with the aim to provide optimal patient care. The proposed vaccine recommendations include immunization against Haemophilus influenzae type b, pertussis, pneumococci, meningococci, tetanus, diphtheria, hepatitis A and B, measles, mumps and rubella, influenza, poliomyelitis, varicella-zoster virus, human papilloma virus, and tick-borne encephalitis with a particular focus on vaccination of patients with active chronic GVHD. 相似文献