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Objective: To determine whether genetic amniocentesis performed in the second trimester of pregnancy is associated with the risk of preterm delivery. Study design: Case–control study performed in several departments of obstetrics and gynaecology of nine European countries. Three thousand and ninety-one preterm births and 5298 controls randomly selected from singleton births born at term during 1994–1997 were analysed. Logistic regression models were used to compare preterm births altogether and, separately, spontaneous preterm delivery and induced preterm delivery. Results: An increased risk of preterm delivery was found in women having second trimester genetic amniocentesis after taking account of other risk factors and confounding variables (odds ratios (OR)=1.59, 95% confidence intervals (95% CI): 1.31–1.92). The association was statistically significant and similar for spontaneous preterm delivery and induced preterm delivery. Conclusion: The study shows an association between preterm delivery and genetic amniocentesis. In view of the wide use of amniocentesis, further research on the etiologic role of this prenatal diagnostic technique is needed.  相似文献   
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Patterns of EEG dysfunction in clinical psychiatry are badly documented. Population variables in patients admitted to the psychiatric ward of a general hospital (n = 1,285) compared to a sample referred for EEG recording (n = 1,200) are reported. Prevalence of EEG dysfunction in referrals is high (42.5%) and the reported selection criteria appear clinically valid. The type of EEG dysfunction largely depends on age and recognizable patterns in general hospital psychiatry include drug effects, epilepsy in mental retardation and organic brain syndromes in the elderly. Similar data in other types of mental institutions are highly mandatory.  相似文献   
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Akt/PKB is a serine/threonine protein kinase that regulates cell cycle progression, apoptosis and growth factor mediated cell survival in association with tyrosine kinase receptors. The protein is a downstream effector of erbB-2 with implications in breast cancer progression and drug resistance in vitro. We aimed to examine the role of Akt-1 in breast cancer patients, by determining whether the expression (Akt-1) and/or activation (pAkt) were related to prognostic markers and survival. The expression of erbB-2, heregulin beta 1 and Bcl-2 was also assessed by flow cytometry or immunohistochemistry. This study comprised 93 patients, aged <50 who were treated with tamoxifen and/or goserelin. We found that pAkt was associated with lower S-phase fraction (P=0.001) and the presence of heregulin beta 1-expressing stromal cells (P=0.017). Neither Akt-1 nor pAkt was related with other factors. Tumour cells-derived heregulin beta 1 was found mainly in oestrogen receptor negative (P=0.026) and node negative (P=0.005) cases. Survival analysis revealed that pAkt positive patients were more prone to relapse with distant metastasis, independently of S-phase fraction and nodal status (multivariate analysis; P=0.004). The results suggest that activation of Akt may have prognostic relevance in breast cancer.  相似文献   
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BACKGROUND: The prevalence of chronic obstructive pulmonary disease (COPD) according to guidelines of today seems considerably higher than has been reported also in recent literature. AIM: To estimate the prevalence of COPD as defined by British Thoracic Society (BTS) criteria and the recent global initiative for chronic obstructive lung disease (GOLD) criteria. Further aims were to assess the proportion of underdiagnosis and of symptoms in subjects with COPD, and to study risk factors for COPD. METHODS: In 1996, 5892 of the Obstructive Lung Disease in Northern Sweden (OLIN) Study's first cohort could be traced to a third follow-up survey, and 5189 completed responses (88%) were received corresponding to 79% of the original cohort from December 1985. Of the responders, a random sample of 1500 subjects were invited to a structured interview and a lung function test, and 1237 of the invited completed a lung function test with acceptable quality. RESULTS: In ages >45 years, the prevalence of COPD according to the BTS guidelines was 8%, while it was 14% according to the GOLD criteria. The absolutely dominating risk factors were increasing age and smoking, and approximately a half of elderly smokers fulfilled the criteria for COPD according to both the BTS and the GOLD criteria. Family history of obstructive airway disease was also a risk factor, while gender was not. Of those fulfilling the BTS criteria for COPD, 94% were symptomatics, 69% had chronic productive cough, but only 31% had prior to the study been diagnosed as having either chronic bronchitis, emphysema, or COPD. The corresponding figures for COPD according GOLD were 88, 51, and 18%. CONCLUSIONS: In ages >45 years, the prevalence of COPD according to the BTS guidelines was 8%, and it was 14% according to the GOLD criteria. Fifty percent of elderly smokers had developed COPD. The large majority of subjects having COPD were symptomatic, while the proportion of those diagnosed as having COPD or similar diagnoses was small.  相似文献   
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