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71.
72.
Based on a standardized in-vitro method for quantifying the activity of prostaglandin-synthetase by means of coupling malondialdehyde with 2-thiobarbituric acid the possibility of using this method also as ex-vivo technique is described. By this, more favourable prerequisites to pharmacological valuation of the effects of potential antiinflammatory substances exists compared to the application of in-vitro results, only.  相似文献   
73.
Dose-response curves of angiotensin I (AI, 1.0-1000.0 pmol) and angiotensin II (AII, 1.25-1250.00 pmol) were obtained in isolated rat hearts subjected to control conditions, mild hypoxia (PO2 = 145 mm Hg), reoxygenation, ischemic (perfusion pressure = 35 mm Hg) and reperfusion. Both AI and AII caused dose-dependent coronary flow (CF) of 26 +/- 3 and 27 +/- 2%, respectively. The effects of both AI and AII were substantially attenuated during hypoxia, but were fully restored upon reoxygenation. During ischemia, the effect of AII was unaltered while the effect of AI was enhanced compared to the control (P less than 0.05). This enhancement was reversible on reperfusion. Cardiac conversion of AI, calculated from ED50 values for AI and AII, was significantly increased during ischemia (P less than 0.05). Infusion of saralasin (0.5-5.0 micrograms/min) did not increase CF in any of the groups. We conclude that (1) the coronary vasoconstrictive effect of AII is preserved in ischemia but attenuated in hypoxia and (2) cardiac conversion of AI to AII is enhanced in hearts injured by ischemia.  相似文献   
74.
A case of testicular cancer in 2 brothers is reported and a review of the literature about testicular malignancies and etiologic factors in closely related family members is given. The familial incidence of testicular tumor is found to be 3% in twins and 0.6-2.1% in less closely related men. Tumors were of the same histology in 70-77% of the twins, whereas in brothers and in other degrees of relationship tumors of different histology mostly occur. Following the diagnosis of the tumor in the first man, the average interval to presentation of the tumor in the relative was 3.7 years in twins, 7.7 years in nontwin brothers and 13.5 years for less closely related men. The need for a thorough checkup of other family members is advised.  相似文献   
75.
This study compares the weight of the human brain to gestational age and body dimensions. A new formula for calculating the rate of growth is proposed. It consists of a second order polynomial function: Y = A0 + A1X + A2X2, in which Y is brain weight, body weight, height, or body surface area; X is gestational age in weeks and A0, A1, and A2 are statistically estimated coefficients. In utero, the growth rate is most rapid for body weight, followed in decreasing order by brain weight, body surface area, and height. Brain growth is the same for both sexes in black and white races; it accelerates between the 20th and 45th weeks of gestation. The size of the newborn infant brain is directly related to gestational age and body size and is not determined by sex or race.  相似文献   
76.
BACKGROUND: The efficacy of nasal continuous positive airway pressure (nCPAP) as a prophylactic method for preventing cardiopulmonary complications after major vascular surgery has not been investigated. PATIENTS/METHODS: In a prospective randomized trial, 204 patients undergoing elective midline laparotomy for vascular surgery were randomized to receive standard therapy ( n=105) or additional prophylactic nCPAP ( n=99) for the first postoperative night. Postoperative oxygenation, incidence of severe cardiac, and pulmonary complications, length of intensive care surveillance and length of total postoperative hospital stay (LOS) were compared. RESULTS: Prophylactic nCPAP significantly reduced the number of patients with severe oxygenation disturbances defined as paO(2) < 70 mmHg with FiO(2) > or = 0.7 (5 versus 17, P=.01). There were no differences with respect to death, cardiac and pulmonary complications, length of intensive care surveillance or LOS. CONCLUSION: Prophylactic 12 h nCPAP significantly reduces the occurrence of postoperative oxygenation disturbances but has no effect on cardiac or pulmonary complications, need for intensive care, LOS or mortality after major vascular surgery.  相似文献   
77.
Interest in inguinal hernia surgery has increased significantly with the introduction of new operating techniques during the past decade. This multicenter study compared short-term results in patients treated by the laparoscopic transabdominal preperitoneal patch technique (TAPP; n=518) and the Shouldice technique (n=524). We evaluated demographics, operative data, complications, hospital stay, postoperative pain, use of analgesics, functional status, sick leave, and complaints up to 3 months postoperatively. The median operating time was shorter in the Shouldice group (55 vs. 65 min), but there were no significant differences in complication rates, and major complications were rare. The hospital stay was 1 day or less in over 98% of cases in both groups, but more operations were performed on outpatient basis in the Shouldice group. In the TAPP group postoperative pain and analgesic consumption were less, postoperative functional status was better, and sick leave was shorter (10 vs. 14 days). These results show that the two methods are equally safe and have few major complications. The TAPP operation is associated with less postoperative pain, better postoperative functional status, and shorter sick leave, but at the price of a longer operating time. Electronic Publication  相似文献   
78.
79.
In 50 children, 4 months to 12 years of age, with minor head trauma non-target visual event-related potentials were performed and compared to a second registration of the potentials some months later. On following-up there was a clear tendency for a relative improvement of the latencies of the endogenous potentials. In this way non-target visual event-related potentials proved to be of value in the investigation of mental impairment in early childhood.  相似文献   
80.
Summary The prevalence of smoking, hypertension and diabetes mellitus was assessed in 221 patients suffering from internal carotid stenosis and compared with the prevalences in two sex- and age-matched control groups composed of subjects having normal Doppler findings and from non-neurological outpatients. Of the subjects with carotid stenosis 27.6% were hypertensive smokers in comparison with 9.5% and 17.2% in the two control groups. The difference of the stenosis cohort from the two control groups was significant (P<0.01 and P=0.016 respectively). There was no statistically significant differences between the occurrence of diabetes and hypertension in non-smokers and patients who smoked. In 394 investigated patients suffering from carotid stenosis or occlusion an obstruction index, based on the Doppler shift frequency, was calculated. This index was lowest in the normotentive non-smokers. It was only insignificantly higher in the hypertensive non-smokers but significantly so in the normotensive smokers. The index was highest in the hypertensive non-smokers. It was concluded that cigarette smoking, especially if associated with hypertension, is a determinant risk factor for carotid stenosis and occlusion.  相似文献   
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