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991.
RA Dr. U. Baur 《Der Gyn?kologe》2005,38(2):172-173
Ohne Zusammenfassung 相似文献
992.
RA R.-W. Bock 《Der Gyn?kologe》2004,37(1):51-55
Risk management in clinics—and also in private practice—represents an instrument for damage prevention by actively seeking risk fields. That dealing with the occurrence of a complication or incident in itself constitutes a risk field is often underrated. Clinics are equipped to react appropriately to deviations from the planned treatment course or in emergency situations. Risk management analyses, however, indicated that often there are no established procedures for managing the legal consequences of incidents beyond the requirements of medical attention. This can result in far-reaching detrimental consequences for those directly involved, for the specialist department, and the entire clinic. As a result, methods to minimize risks and damage should be implemented, also in view of possible legal consequences. Precisely this is the goal of risk management. 相似文献
993.
水通道蛋白9表达与大鼠缺血性脑水肿形成的关系 总被引:1,自引:0,他引:1
目的:研究水通道蛋白9(Aquaporin9,AQP9)在大鼠缺血性脑组织中的表达及其与脑水肿形成之间的关系.方法:采用线拴法制作大鼠局灶性脑缺血模型,通过光镜、电镜技术观察脑水肿区的病理变化,干湿重法检测脑含水量,采用原位杂交、免疫组化方法观察AQP9及其mRNA在脑组织中的表达.结果:缺血后细胞及血管周围间隙明显扩大,部分细胞坏死,胶质细胞增生;大鼠穹隆下器官、脉络丛、大脑皮质、视上核、海马等部位AQP9及其mRNA的表达上调,48~72h达峰值;脑组织含水量亦在72h达高峰.结论:随缺血性脑水肿的出现,AQP9及其mRNA表达上调,提示AQP9可能在缺血性脑水肿的形成中发挥重要作用. 相似文献
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997.
Rodent non-genotoxic hepatocarcinogens such as nafenopin suppress
spontaneous and transforming growth factor beta1 (TGFbeta1)-induced rat
hepatocyte apoptosis as well as inducing DNA synthesis. We wished to
determine if these two processes are associated. In primary rat
hepatocytes, nafenopin suppressed apoptosis from 1.9 to 0.63% but more
apoptotic bodies were bromodeoxyuridine (BrdU)-labelled (0.35%) than
predicted statistically from a random distribution of apoptosis within the
cycling and non-cycling populations (0.10%). In contrast, TGFbeta1 induced
hepatocyte apoptosis (7.8%) but fewer hepatocytes were BrdU- labelled
(0.29%) than predicted (0.82%). Western blot analyses showed that nafenopin
and TGFbeta1 had opposing effects on cyclin-dependent kinase 4 (CDK4)
protein: nafenopin elevated CDK4 compared with controls, whereas TGFbeta1
caused a reduction. These data suggest that non-genotoxic hepatocarcinogens
suppress apoptosis in the non-cycling population of hepatocytes and elevate
CDK4 levels, possibly allowing potentially tumourigenic cells to enter the
cell cycle.
相似文献
998.
RA Clarke ZH Fang PJ Marr CS Lee JH Kearsley G Papadatos 《Journal of Medical Imaging and Radiation Oncology》2002,46(3):329-335
The ataxia telangiectasia (A–T) gene (ATM) is a dominant breast cancer gene with tumour suppressor activity. ATM also regulates cellular sensitivity to ionising radiation (IR) presumably through its role as a facilitator of DNA repair. In normal cells and tissues the ATM protein is rapidly induced by IR to threshold/maximum levels. The kinase function of the ATM protein is also rapidly activated in response to IR. The fact that women carriers of ATM mutations can have an increased risk of developing breast cancer and that many sporadic breast tumours have reduced levels of the ATM protein broadens the scope of ATM's tumour suppressor within the breast. This report describes the downregulation of ATM protein levels in a radiosensitive breast cancer patient. Postinduction ATM levels were up to tenfold lower in the patient's fresh tissues compared to normal controls. These results might indicate a much broader role for ATM anomalies in breast cancer aetiology. 相似文献
999.
JW Kendig RM Ryan RA Sinkin WM Maniscalco RH Notter R Guillet C Cox HS Dweck MJ Horgan LJ Reubens H Risemberg DL Phelps 《Pediatrics》1998,101(6):1006-1012
INTRODUCTION: Previous trials of surfactant therapy in premature infants have demonstrated a survival advantage associated with prophylactic therapy as an immediate bolus, compared with the rescue treatment of established respiratory distress syndrome. The optimal strategy for prophylactic therapy, however, remains controversial. When administered as an endotracheal bolus immediately after delivery, surfactant mixes with the absorbing fetal lung fluid and may reach the alveoli before the onset of lung injury. This approach, however, causes a brief delay in the initiation of standard neonatal resuscitation, including positive pressure ventilation, and is associated with a risk for surfactant delivery into the right main stem bronchus or esophagus. As an alternative approach, surfactant prophylaxis may be administered in small aliquots soon after resuscitation and confirmation of endotracheal tube position. Although this strategy has substantial logistical advantages in clinical practice, its efficacy has not been established. OBJECTIVE: The purpose of this study was to determine whether the established benefits of the immediate bolus strategy for surfactant prophylaxis could still be achieved using a postventilatory aliquot strategy after initial standard resuscitation and stabilization. DESIGN: Multicenter randomized clinical trial with patients randomized before delivery to immediate bolus or postventilatory aliquot therapy. PARTICIPANTS: Inborn premature infants delivered to mothers at an estimated gestational age of 24[0/7] to 28[6/7] weeks. INTERVENTIONS: Those infants who were randomized to the immediate bolus strategy were intubated as rapidly as possible after birth, and a 3-mL intratracheal bolus of calf lung surfactant extract (Infasurf) was administered before the initiation of positive pressure ventilation. Those infants who were randomized to the postventilatory aliquot strategy received standard resuscitation measures with intubation by 5 minutes of age, if not required earlier. At 10 minutes after birth, 3 mL of surfactant was administered in 4 divided aliquots of 0.75 mL each. Patients in both groups were eligible to receive up to three additional doses of surfactant as rescue therapy in the neonatal intensive care unit, if needed. OUTCOME MEASURES: The primary outcome variable was survival to discharge to home. Secondary variables included neonatal complications and requirement for oxygen therapy at 36 weeks' postmenstrual age. RESULTS: Among three centers, 651 infants were enrolled and randomized before delivery. Survival to discharge to home was similar for the two strategies for surfactant therapy as prophylaxis: 76% for the immediate bolus group and 80% for the postventilatory aliquot group. In a secondary analysis, the rate of supplemental oxygen administration at 36 weeks' postmenstrual age was 18% for the immediate bolus group and 13% for the postventilatory aliquot group. CONCLUSIONS: Survival to discharge to home was similar with immediate bolus and postventilatory aliquot strategies for surfactant prophylaxis. Because of its logistical advantages in the delivery room and its beneficial effects on prolonged oxygen requirements, we recommend the postventilatory aliquot strategy for surfactant prophylaxis of premature infants delivered before 29 weeks' gestation. 相似文献
1000.
OBJECTIVE: Premature infants are susceptible to bronchopulmonary dysplasia (BPD), a chronic lung disease of infancy that appears to be caused in part by oxidative stress from hyperoxia. To investigate the possible role of nitric oxide-derived oxidants such as peroxynitrite in the etiology of BPD, we measured levels of plasma 3-nitrotyrosine, which is produced by the reaction of peroxynitrite with proteins. PATIENTS AND METHODS: Ten premature infants who developed BPD, defined as requiring supplemental oxygen beyond 36 weeks' postmenstrual age, were identified retrospectively from a group of subjects enrolled in a clinical trial of antenatal therapy. Serial plasma samples had been collected on these infants during the first month of life as part of the trial. Sixteen comparison premature infants were identified from the same population: 5 had no lung disease, 6 had respiratory distress syndrome that resolved, and 5 had residual lung disease at 28 days of life that resolved by 36 weeks' postmenstrual age. Plasma 3-nitrotyrosine levels were measured using a solid phase immunoradiochemical method. RESULTS: All 3-nitrotyrosine values in infants without BPD were <0.25 ng/mg protein, and levels did not change with postnatal age. Plasma 3-nitrotyrosine concentrations were significantly higher in infants with BPD, increasing approximately fourfold during the first month of life. For the 20 infants who had blood samples available at 28 days of life, plasma 3-nitrotyrosine levels correlated with the fraction of inspired oxygen that the infant was receiving (r = 0.7). CONCLUSION: Plasma 3-nitrotyrosine content is increased during the first month of life in infants who develop BPD. This suggests that peroxynitrite-mediated oxidant stress may contribute to the development of this disease in premature infants and that 3-nitrotyrosine may be useful as an early plasma indicator of infants at risk for developing BPD. 相似文献