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71.
72.
Carrie L. Randall PhD Raymond F. Anton MD Howard C. Becker PhD 《Alcoholism, clinical and experimental research》1988,12(3):412-416
The purpose of this study was to determine the role of alcohol-induced maternal hypothermia in the teratogenic actions of alcohol. C57BL/6J mice were administered an acute dose of alcohol (5.8 g/kg orally) or isocaloric sucrose on day 10 of gestation. One half of each group was placed for 6 hr in an incubator set at 32 degrees C and the other half was housed in the incubator at room temperature (22 degrees C). As expected, acute prenatal alcohol exposure at this time of gestation was associated with decreased birth weight and an increase in limb and kidney malformations. The significant alcohol x environmental temperature interaction on these dependent variables indicated that the teratogenic insult was not attenuated, but was in fact even greater for the 32 degrees C/alcohol group. An absence of a main effect of environmental temperature indicated that the 32 degrees C environment, per se, was not teratogenic. Thus, maternal hypothermia is probably not an etiological factor in animal models of fetal alcohol syndrome. Moreover, antagonism of alcohol-induced maternal hypothermia exacerbates the teratogenic actions of alcohol observed at room temperature. 相似文献
73.
The early and late results of bypass surgery in 124 patients with unresectable oesophageal cancer are reported. Patients were grouped according to the extent of disease: group A, tumour localized to the oesophagus where severe pulmonary disease contra-indicated oesophagectomy (n = 9); group B, tumour less than or equal to 10 cm in length with mediastinal invasion (n = 81); group C, tumour greater than 10 cm in length with mediastinal invasion and/or fixed malignant lymph nodes (n = 33). Extent of disease was not recorded in one patient. The operative mortality was 4 per cent but 9 other patients died in hospital (hospital mortality, 11 per cent). Mortality was increased in patients undergoing colon bypass and in those with a large tumour load but these differences failed to reach statistical significance. The most frequent complication was neck sepsis, secondary to leakage from the proximal end of the excluded oesophagus. Eighty-nine per cent of the survivors could eat a normal, unrestricted diet on discharge and eighty-two per cent of survivors had complete and lasting relief from dysphagia. Median survival after bypass was 5 months but survival was significantly improved by radiotherapy to the tumour (P less than 0.001). Gastric bypass with radiotherapy is indicated in patients with extra-oesophageal spread of malignancy and in patients with tumours localized to the oesophagus who are unfit for resection. Bypass surgery may be contra-indicated in patients with a primary tumour greater than 10 cm in length and/or fixed lymph node metastases because mortality is increased and survival after operation is short. 相似文献
74.
Urine testing for drug use in the workplace is now widespread, with the prevalence of positive drug tests in the work force being 0% to 15%. The prevalence of marijuana use is highest of the illicit drugs being tested. Highly prevalent drugs can be reliably tested. Although it is prudent to rid the workplace of drug use, there is little scientific study on the relationship of drug use and workplace outcomes, such as productivity and safety. Probable-cause testing and preemployment testing are the most common applications. Random testing has been less accepted owing to its higher costs, unresolved legal issues, and predictably poor test reliability. Legal issues have focused on the right to privacy, policy agreements, discrimination, and the lack of due process. The legal cornerstone of a good program is a policy that is planned and agreed on by both labor and management, which serves both as a contract and as a procedure in which expectations and consequences are known. Moreover, NIDA is certifying laboratories doing employee drug testing. Testing methods, when done correctly, are less prone to error than in the past, but screening tests can be defeated by adulterants. Although the incidence of false-positive results is low, such tests are less reliable when the prevalence of drug abuse is also low. 相似文献
75.
Background
While the mortality of esophageal surgery has decreased due to technological advancements, there is still a complication rate of about 30%. One of the main complications is the anastomotic leakage associated with a significant rate of morbidity and mortality. To close the leakage the efficacy of self-expanding stents (SES) has been shown in different studies. However, the high rate of stent migration limits the use of commercial available stents. In our case we were faced with the problem that the diameter of all available stents was too small to attach tightly to the mucosal wall of the esophagogastric anastomosis. 相似文献76.
77.
D M Becker T J Saunders B Wispelwey D C Schain 《The American journal of the medical sciences》1992,303(6):395-397
Recently, the authors managed three patients with AIDS and venous thromboembolism. All three were active, ambulatory, and without known risk factors for pulmonary embolism or deep venous thrombosis. One patient had a low titer for IgG anticardiolipin antibody (1:13). Two had low normal values for free protein S, and the third patient had a very low value (5%). Clinicians caring for AIDS patients should be alert to the possibility that venous thromboembolism may complicate HIV infection. 相似文献
78.
We surveyed approximately 850 physicians in eight surgical specialties to investigate physicians' work in performing invasive services. Building on our analysis of physician work, we developed a relative value scale of physicians' services based on resource costs. First, we found that physician charges are not set in proportion to the resources required to perform a given procedure: there is a threefold variation, across hospital-based invasive procedures, in the ratio of charges to resource-based relative values. Second, for most procedures, the preoperative and postoperative periods represent 60% to 75% of a physician's total service time, but only 35% to 50% of the total service work. Lastly, intraoperative work per unit of time varies greatly. Work per minute for invasive procedures is two to three times that of medical office visits and is strikingly greater for some specialties. The Resource-Based Relative Value Scale, at a minimum, represents a useful tool for payers to identify procedures with potentially aberrant charges and also offers unique insights into the nature of physicians' work. 相似文献
79.
For the first time histomorphological findings of the uteroplacental vessels were correlated with Doppler flow parameters of this vascular area in a combined study. The study group consisted of 58 women with a pregnancy-induced hypertension or an otherwise presumed uteroplacental perfusion impairment delivered by cesarean section. The control group included 50 healthy pregnancies, delivered by cesarean section due to presentation anomalies or failure to proceed. After removal of the placenta a placental bed biopsy containing the uteroplacental vessels of the decidual and inner myometrial layer was taken. The occurrence of accepted histological signs of low uteroplacental perfusion was compared to Doppler flow velocity wave forms in uteroplacental arteries. The accuracy of doppler-sonographic findings of uteroplacental circulatory impairment confirmed by the histomorphological results was high, even in cases not complicated by hypertension. The good accordance of Doppler flow parameters with morphological findings offers new perspectives for differentiated insights in pregnancy courses with and without signs of uteroplacental insufficiency. 相似文献
80.
Nervous control of gastric and pancreatic secretory response to 2-deoxy-D-glucose in the dog 总被引:1,自引:0,他引:1
The relative contribution of the vagus and splanchnic nerves as mediators of the action of 2-deoxy-D-glucose (2-DG) on the stomach and the pancreas is largely unknown. In conscious dogs with gastric and pancreatic fistulas, the effect of 2-DG (100 mg kg-1, given as an intravenous bolus) on gastric acid and pancreatic exocrine secretion was tested before and after bilateral truncal vagotomy and after truncal vagotomy plus celiac and superior mesenteric ganglionectomy (i.e. extrinsic denervation of the stomach and the pancreas). In another set of dogs, only ganglionectomy was performed and the same experiments were done as in the first set of dogs. With the extrinsic nerves intact, 2-DG caused a rapid (within 15 min) and prolonged increase in gastric acid output as well as in pancreatic flow rate, bicarbonate and protein output. Truncal vagotomy abolished the gastric acid and pancreatic secretory response to 2-DG; additional ganglionectomy had no further effect. Ganglionectomy alone did not significantly alter 2-DG-stimulated gastric acid output, pancreatic flow rate and bicarbonate output; protein output, however, was significantly diminished by 57%. These results indicate that (a) intravenous 2-DG is a potent stimulant of gastric acid and pancreatic bicarbonate and protein output; (b) the vagus nerves are the major mediators of the gastric and pancreatic secretory response to 2-DG; (c) the sympathetic nerve fibers running through the celiac and superior mesenteric ganglia are probably not involved in the mediation of the 2-DG-induced gastric acid and pancreatic bicarbonate secretion. The diminished protein response to 2-DG after ganglionectomy is probably due to cut vagal fibers running through these ganglia. 相似文献