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991.
Purpose: A matched case–control study of all pregnancies obtained after either IVF or ICSI was conducted to investigate the perinatal outcome. Methods: Three hundred eleven singleton and 115 twin pregnancies obtained after assisted reproduction were studied. Controls were selected from a regional register and were matched for maternal age, parity, singleton or twin pregnancy, and date of delivery. Results: No significant difference was observed for gestational age at delivery, birth weight, incidence of congenital anomalies, and incidence of perinatal mortality between ART (singleton and twin) pregnancies and spontaneous controls. ART twin pregnancies showed a higher incidence of preterm deliveries than control pregnancies (52 vs 42%; P < 0.05) and needed more neonatal intensive care (47 vs 26%; P < 0.05). Conclusions: From this case–control study it is concluded that the perinatal outcome of ART singleton pregnancies is not different from that in matched controls. ART twin pregnancies showed a higher incidence of preterm deliveries than control pregnancies and needed more neonatal intensive care.  相似文献   
992.
Eighteen obese women (body mass index 30 +/- 6.1 kg/m2) with hyperinsulinaemia and with the polycystic ovary syndrome took octreotide at the dose of 100 mug s.c. The effect of the drug was assessed on plasma levels of gonadotropins luteinising hormone (LH), follicle stimulating hormone (FSH), of insulin, insulin-like growth factor-1 (IGF-1), androstenedione, testosterone, dehydroepiandrosterone sulphate (DHEAS), sex hormone binding globulin (SHBG) and insulin-like growth factor-binding protein-3 (IGFBP-3). Octreotide significantly reduced LH (31.8%), insulin (52%), IGF-1 (14%), androstenedione (22.6%) and testosterone (20%) and increased IGFBP-3 (25%).  相似文献   
993.
De Serres G  Gay NJ  Farrington CP 《American journal of epidemiology》2000,151(11):1039-48; discussion 1049-52
Elimination of an infectious disease is often understood to mean the total absence of cases in a population. This situation can occur only if the entire population is immune as a result of either natural disease or vaccination. However, this costly and unrealistic scenario is not necessary to ensure elimination, more appropriately defined as a situation in which sustained transmission cannot occur and secondary spread from importations of disease will end naturally, without intervention. The authors describe the size and duration of outbreaks caused by imported infections after indigenous transmission has been eliminated. They show that the status of the elimination process can be monitored by assessing the proportion of cases imported and the distribution of outbreak sizes. Measles in Canada, the United States, and the United Kingdom provides a good example of the relevance of these criteria. Surveillance of the size and duration of these outbreaks enables maintenance of elimination to be monitored.  相似文献   
994.
In vitro exposure to ecstasy (3,4-methylenedioxymethamphetamine, MDMA) alters some immune parameters such as T-cell regulatory function, cytotoxic T-lymphocyte activity, natural killer cell activity and macrophage function. Administration of MDMA in rats produces a suppression of lympho-proliferation response and a decrease in circulating lymphocytes, accompanied by an increase in plasma corticosterone. It was postulated a direct action of MDMA on lymphocytes or rather an indirect action mediated by the hypothalamic pituitary adrenal axis (HPA-AXIS) and/or the sympathetic nervous system (SNS). Acute MDMA treatment effected on healthy-volunteers produces an immune dysfunction associated with pharmaceutical characteristics and so with MDMA plasma concentrations. There is a decrease in CD4+ T-cells and functional responsiveness of lymphocytes, while percentage of natural killer cells increases. A contemporary rise of cortisol plasma concentrations supports the hypothesis of MDMA-induced release of corticotrophin-releasing factor from the hypothalamus and subsequent HPA-axis and SNS activation.  相似文献   
995.
We studied the influence of oligofructose (OFS), a nondigestible fructan, on lipid metabolism in obese fa/fa Zucker rats. The addition of 10 g/100 g OFS to the diet slowed the increase in body weight without modifying serum triglycerides or glucose concentrations after 7 wk of treatment. However, an oral load of 2 g glucose and 5 g corn oil/kg body weight increased triglyceridemia more in OFS-fed rats than in control rats. After 10 wk, OFS decreased the hepatic concentration of triglycerides 57% relative to controls. The less severe steatosis was confirmed by histologic analysis. Among the key enzymes involved in fatty acid synthesis and esterification, only malic enzyme activity was significantly lower in OFS-fed rats than in controls. The epididymal fat mass was significantly lower in OFS-fed rats. In conclusion, dietary enrichment with OFS can counteract both the fat mass development and the hepatic steatosis that occur in obese Zucker rats. Future studies will be designed to clarify in obese animals the influence of dietary OFS on postprandial triglyceridemia, which is an important variable associated with the development of atherosclerosis in humans, and to analyze the biochemical mechanism underlying the "hepatoprotective" effect of OFS.  相似文献   
996.
997.
The prognosis of Marfan syndrome in both adult and pediatric patients is primarily related to the cardiovascular complications. In infantile Marfan syndrome, although involvement of the mitral valve is the most frequently encountered cardiovascular lesion, the aortic root can be more worrisome because of its excessive dilatation, leading to aortic insufficiency or dissection. If the role of elective surgery is relatively well defined for adult patients, it is still debated during childhood. We report two patients, aged 22 months and 5 years, each presenting an aortic root aneurysm related to Marfan syndrome, and each treated with the Bentall procedure without specific age-related mortality or morbidity. These two patients experienced normal growth and were free of any complication for a follow-up period of 8 and 2 years, respectively. More than an absolute value of the aortic root dimension, it is the conjunction of the rate of progression of the aortic root dilatation, the degree and the duration of the aortic valve regurgitation, and its resulting left ventricular dysfunction that must be taken into consideration in choosing the surgical option.  相似文献   
998.
This study reports the evaluation of the results of 80 stapedotomies in patients with bilateral otosclerosis. All pre- and postoperative audiological data, together with all relevant information of the operations, were stored in a database and analysed retrospectively. A new approach has been developed in order to evaluate the benefit of second ear stapes surgery in a more disability-orientated way using the AMA-criteria in the Guides to the Evaluation of Permanent Impairment. In all patients the percentage of Binaural Hearing Impairment (BHI) and the percentage of Impairment of the Whole Person (IWP) were determined according to the AMA-criteria. In patients who had both operations at the Academic Medical Centre it was found after the first operation that there was an important decrease in the BHI-percentage (from 26% to 10%) as well as for the IWP-percentage (from 9% to 4%). In addition, the percentages dropped significantly after the second operation (from 11% to 7% and from 4% to 2%, respectively). During follow-up there were no serious complications. It is concluded that bilateral stapedotomy is a safe procedure with good results.  相似文献   
999.
Objective. The European Eureka project ‘Artificial larynx’ aims at realizing an implantable artificial larynx, consisting of artificial vocal folds, artificial epiglottis, tissue connector for tracheal fixation and valve mechanism to switch between breathing and speaking. The last part has been realized. Because its functioning is identical to a tracheostomal valve, it was tested as such. Materials and methods. The device consists of two valves: a speech valve, that will be open during normal breathing and closed by strong expiration and a cough valve that opens during coughing and closes automatically during inhalation. Magnets keep the valves in the breathing position. The magnetic force can be varied. Several prototypes have been tested in vitro and in situ. Results. The prototypes showed good in vitro behaviour. The range of adjustability of speech and cough was wide enough, flow resistance acceptable. This was confirmed by preliminary in vivo experiments. Patients were enthusiastic; hands-free speaking and coughing is possible. Conclusion. Numerous problems have to be solved to produce an artificial larynx. Each solution generated up till now, however, can already be applied to improve the existing rehabilitation process of laryngectomized patients.  相似文献   
1000.
We report a 3-year, 5-month-old boy with an adrenocortical carcinoma. These tumours are rare and highly malignant in childhood. In most cases they are functional, secreting adrenocortical hormones. In this case there was a misleading coexistence with a second abdominal neoplasm, which was a ganglioneuroma; this is a rare benign tumour arising from the sympathetic nervous system. The imaging investigations and their findings are discussed and correlated with pathology. Received: 15 January 1997 Accepted: 15 October 1997  相似文献   
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