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排序方式: 共有1717条查询结果,搜索用时 15 毫秒
71.
Jiyoung Ahn Christine B Ambrosone Peter A Kanetsky Chunqiao Tian Teresa A Lehman Silke Kropp Irmgard Helmbold Dietrich von Fournier Wulf Haase Marie Luise Sautter-Bihl Frederik Wenz Jenny Chang-Claude 《Clinical cancer research》2006,12(23):7063-7070
PURPOSE: Because radiotherapy exerts cytotoxic effects via generation of massive oxidative stress, we hypothesized that catalase, manganese superoxide dismutase, myeloperoxidase (MPO), and endothelial nitric oxide synthase (eNOS) genotypes might result in greater risk of radiotoxicity. EXPERIMENTAL DESIGN: Cases (n = 446) were Caucasian women with breast cancer who received radiotherapy following lumpectomy. Genotypes were determined by matrix-assisted laser desorption/ionization time-of-flight. The development of acute reactions (moist desquamation) associated with genotypes was modeled using the Cox proportional hazards model, accounting for cumulative biologically effective radiation dose. RESULTS: Genotypes associated with higher levels of reactive oxygen species (ROS) were not associated with risk of radiotoxicity. However, relationships between overweight/obesity [body mass index (BMI), >25] and radiotoxicity risk seemed to be modified by eNOS and MPO genotypes associated with higher generation of nitric oxide and ROS, respectively. Women with high BMI (>25) and eNOS GG genotypes were at more than a 6-fold increase in risk (hazard ratio, 6.39; 95% confidence interval, 2.53-16.15) compared with those with BMI <25, and for MPO, those with high BMI (>25) and GG genotypes also had greater risk of radiotoxicity (hazard ratio, 3.61; 95% confidence interval, 1.78-7.35) compared with those with BMI <25. Overweight/obesity was not a strong risk factor among women with other eNOS and MPO genotypes. Exploratory analysis using classification and regression trees indicated that total number of risk alleles contributed, in part, to acute toxicity outcomes among a subgroup of women. CONCLUSIONS: Associations between BMI and radiotoxicity risk may be most apparent among women with genotypes related to higher levels of oxidative stress. Regression trees may be useful in future studies to examine the contributions of multiple factors to individual susceptibility to adverse effects of cancer treatment. 相似文献
72.
OBJECTIVE: Subject of the study was the significance of umbilical artery Doppler velocimetry findings for the further course of pregnancy and fetal outcome in cases of twin pregnancies. METHODS: In 206 cases of twin pregnancy, the umbilical artery was examined using Doppler velocimetry in the median 9 days prior to delivery, and the result was correlated with the further course of pregnancy and fetal outcome. 174 pregnancies showed normal Doppler findings of the umbilical artery (group A), 32 twin pregnancies showed pathological Doppler findings of at least one twin (group B). The median of the maternal age and the parity between the groups were not different. RESULTS: In group B (pathological Doppler findings), intrauterine growth retardation and pre-eclampsia occurred 5 times more often than in group A (normal Doppler findings). The total rate of cesarean sections was not different between the study populations; the rate of deliveries by cesarean section in group B was significantly increased by a factor of 2.4 due to a pathological CTG. The median birth weight and the gestational age at birth were significantly lower in group B (1,660 g; 35 weeks) as compared to group A (2,460 g; 37 weeks; p<0.001). In group B, the rate of premature deliveries up to reaching the 34th week of gestation was 3. 4 times higher; the rate of SGA newborns was 6.3 times higher. Perinatal mortality was increased by a factor of 1.5 in group B compared to group A. CONCLUSION: The Doppler velocimetry findings have considerable effects on the further course of a multiple pregnancy. In case of pathological Doppler findings, early hospitalization and close monitoring of the pregnancy should be performed. In cases of additional pathological findings (maternal illness, pathological Doppler findings of fetal blood vessels), termination of the pregnancy has to be considered. 相似文献
73.
74.
Background: Anaesthetic practice for caesarean section has changed during the last decades. There is a world-wide shift in obstetric anaesthetic practice in favour of regional anaesthesia. Current data concerning anaesthetic practice in patients under-going caesarean section from Germany are not available. A comparison with figures from the UK, USA, Norway and other European countries might be of general interest.
Methods: Questionnaires on the practice of anaesthesia for caesarean section and anaesthetic coverage of the obstetric units were sent to 1178 university, tertiary care, district, community and private hospitals in Germany.
Results: The 532 completed replies of this survey represent 46.9% of the German obstetric units. Most hospitals (42.3%) have delivery rates between 500 and 1000 per year. General anaesthesia is the most common anaesthetic technique for elective (61%), urgent (83%) and emergency caesarean section (98%). Epidural anaesthesia is performed in 23% of scheduled and 5% of non-scheduled caesarean sections, and spinal anaesthesia in 14% and 10%, respectively. Acid aspiration prophylaxis before elective caesarean section is used in 68.7% of the departments. The majority of the departments provide a 24-hour anaesthetic coverage; however, in only 6.2% of the units, this service is assigned to obstetric anaesthesia, exclusively.
Conclusion: Compared to data from 1978, anaesthetic practice for caesarean section has changed with an increase in regional anaesthesia. However, German anaesthetists prefer general anaesthesia for caesarean section. In contrast, anaesthetists in other countries predominantly use regional techniques, and the difference to German practice is striking. International consensus discussion and recommendations as well as comparable European instruments of quality control in obstetric anaesthesia are desirable. 相似文献
Methods: Questionnaires on the practice of anaesthesia for caesarean section and anaesthetic coverage of the obstetric units were sent to 1178 university, tertiary care, district, community and private hospitals in Germany.
Results: The 532 completed replies of this survey represent 46.9% of the German obstetric units. Most hospitals (42.3%) have delivery rates between 500 and 1000 per year. General anaesthesia is the most common anaesthetic technique for elective (61%), urgent (83%) and emergency caesarean section (98%). Epidural anaesthesia is performed in 23% of scheduled and 5% of non-scheduled caesarean sections, and spinal anaesthesia in 14% and 10%, respectively. Acid aspiration prophylaxis before elective caesarean section is used in 68.7% of the departments. The majority of the departments provide a 24-hour anaesthetic coverage; however, in only 6.2% of the units, this service is assigned to obstetric anaesthesia, exclusively.
Conclusion: Compared to data from 1978, anaesthetic practice for caesarean section has changed with an increase in regional anaesthesia. However, German anaesthetists prefer general anaesthesia for caesarean section. In contrast, anaesthetists in other countries predominantly use regional techniques, and the difference to German practice is striking. International consensus discussion and recommendations as well as comparable European instruments of quality control in obstetric anaesthesia are desirable. 相似文献
75.
K. Wulf 《Archives of dermatological research》1954,197(3):209-255
Ohne ZusammenfassungMit 4 Textabbildungen. 相似文献
76.
77.
The shielding effect of various types of human hair and the influence of a shampoo on the transmission of grenz rays were determined by ionization chamber measurements. The mean transmission proved to be 53.7% with clean hair and 48.1% with hair shampooed one week before. P less than 0.05 (n = 50) (Pratt's test). A relationship was found between weight of hair layer and transmission. In clinical practice, the thickness of the hair should be assessed, and the normal skin dose multiplied by 1.5 for patients with a thin hair layer, by 2 in the case of a medium, and by 3 in the case of a thick hair layer. 相似文献
78.
Utian WH MacLean DB Symonds T Symons J Somayaji V Sisson M 《Journal of sex & marital therapy》2005,31(4):271-283
The currently accepted gold standard for diagnosis of female sexual dysfunction (FSD) is a nonstandardized interview by a clinician whose field of expertise is FSD. However, the limited number of experts in the field has implications for running efficient large-scale clinical trials. Therefore, we developed a structured diagnostic method (SDM) to enable diagnosis of FSD in postmenopausal women by health care professionals who are not FSD experts. Our study objectives were to evaluate both convergent validity and intrarater reliability of the SDM. The results showed that the method had good convergent validity and excellent intrarater reliability. Thus, we conclude that the SDM can reliably diagnose FSD status and FSD subtypes in postmenopausal women. 相似文献
79.
Morin AM Eberhart LH Behnke HK Wagner S Koch T Wolf U Nau W Kill C Geldner G Wulf H 《Anesthesia and analgesia》2005,100(5):1503-10, table of contents
Continuous peripheral nerve blocks offer the benefit of extended postoperative analgesia and accelerated functional recovery after major knee surgery. Conventional nerve localization is performed over a stimulating needle followed by blind insertion of the peripheral catheter. Correct catheter placement is confirmed by testing for satisfactory analgesia. Stimulating catheters offer the advantage of verifying correct placement close to the nerve during catheter placement. The aim of this randomized trial was to determine whether accurate catheter positioning under continuous stimulation accelerates the onset of sensory and motor block, improves the quality of postoperative analgesia, and enhances functional recovery. We compared femoral nerve catheters inserted under continuous stimulation with catheters that were placed using the conventional technique of blind advancement in 81 patients undergoing major knee surgery. Time of catheter placement was similar in both groups with 4 min (3/7.3; median, 25th/75th percentile) in the conventional group and 5 min (4/8.8) in the stimulating catheter group. In both groups, 42% of the catheters could be correctly placed (motor response of the patella with a current < or =0.5 mA) at first attempt. In 22 patients (58%) of the stimulating catheter group, the catheter had to be redirected 1-20 times, including 2 that could not be correctly placed within 20 min. The onset time of sensory and motor block was almost similar in both groups. There were no differences in the postoperative IV opioid consumption, and visual analog scale pain scores at rest and movement, or maximal bending and stretching of the knee joint during the 5 days after surgery. We conclude that with continuous femoral nerve blocks, blind catheter advancement is as effective as the stimulating catheter technique with respect to onset time of sensory and motor block as well as for postoperative pain reduction and functional outcome. 相似文献
80.