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981.
The renal and hemodynamic effects of dopamine were measured during the immediate postoperative period in six infants following repair of congenital cardiac defects. Dopamine was infused at rates of 5, 10, and 15 micrograms/kg/min. Cardiac index (CI) increased significantly at a dopamine infusion rate of 15 micrograms/kg/min. The glomerular filtration rate (GFR) and urine output increased at dopamine infusion rates of 5 and 10 micrograms/kg/min and returned to baseline at 15 micrograms/kg/min. No significant changes occurred in right atrial pressure (RAP), left atrial pressure (LAP), systemic artery pressure, systemic vascular resistance (SVR), or pulmonary vascular resistance (PVR). Heart rate (HR) increased slightly at a dopamine infusion rate of 15 micrograms/kg/min. Pulmonary artery pressure (PAP) increased significantly in only one patient. These data demonstrate that infants require high doses of dopamine to produce the hemodynamic effects seen in adults and that these higher doses may be used without adverse renal effects.  相似文献   
982.
Re-orchiopexy was performed in 33 boys (42 testes) in order to place an undescended testis in the scrotum after failure of the initial operation. Success was achieved in 80.9%. Seven of the 10 testes, reported to have short spermatic vessels at the first surgery, had no elongation of the vessels and only 1 of these resulted in a high scrotal location of the testis. It appears that most orchiopexy failures are the result of technical failures of the initial procedure. Standard orchiopexy with extensive mobilization of the spermatic vessels and testis can successfully correct most of the undescended testes. However, the preferred management for the intra-abdominal testis with short vessels may be transection of the spermatic vessels rather than a planned two-stage technique.  相似文献   
983.
A technique is described that allows an end-to-end anastomosis between a vascular prosthesis and a vessel that is much smaller in diameter. This procedure involves enclosing the prosthesis and the vessel while keeping the vascular axis straight without any kinking. In addition, this technique makes little demand on the extensibility of the natural tissue in order to adapt to the prosthesis, which is inextensible.  相似文献   
984.
The authors present two cases of Acland's flap. This flap described and published in 1981, is a very good flap, but the myocutaneous flaps have limited its use. However, the authors believe that there are indications for this saphenous flap. The vascular supply for this flap is a saphenous artery, the last branch of the femoral artery, before it becomes the popliteal artery. The authors report two cases: one neurovascular island flap for the posterior side of the knee, and the other case is a free flap for forearm. This flap is part of a particularly rich arterial network on the medial side of the thigh and of the knee. Masquelet, in 1986, showed that it is possible to raise a periosteal flap or a vascularized tendon flap.  相似文献   
985.
986.
The content of rhodopsin in the eyes of 15 donors (30 eyes) was determined. Both retinal and pigment epithelial fractions were collected from each globe, extracted using 1% CTAB, and the rhodopsin difference spectrum of each fraction was obtained separately. The total amount of rhodopsin, obtained by summing the amounts recovered from the retinal and PE fractions, ranged from 2.00 to 11.94 (median: 6.40) nmoles/eye. Previously reported mean values of about 3.5 to 4.0 nmoles per retina have been obtained using a variety of methods. The present higher values, perhaps largely dependent on procedural details described herein, appear plausible given the known concentrations of rhodopsin in rod outer segments, rod outer segment volumes, and number of rods in the human retina.  相似文献   
987.
Despite standards of living and life expectancy amongst the highest in Europe, Switzerland exhibits fairly substantial social inequities in health. As regards male mortality by socio-economic group, these differentials are both marked and independent of cause of death. There is a wealth of information on morbidity and disability supporting the hypothesis that people in lower socio-economic groups tend to age faster and suffer more at younger ages. It is similarly evident that infants of low class mothers, particularly those unwed, underprivileged immigrant, are at excess risk. The Swiss results are of political and scientific interest in that they suggest that the average wealth of a community does not determine health differentials.  相似文献   
988.
989.
Efficacy of diltiazem in the treatment of diffuse oesophageal spasm   总被引:1,自引:1,他引:0  
Calcium antagonist relax smooth muscle, a possible useful concept in treatment of diffuse oesophageal spasm. Therefore the effects of oral diltiazem (60 mg t.d.s.) and placebo were compared in eight patients with diffuse oesophageal spasm in a 10-week double-blind crossover study. The patients recorded the severity of chest pain and/or dysphagia in daily pain diaries using visual analogue scales. Chest pain index and dysphagia index were calculated by multiplying frequency with daily intensity of each individual symptom. When compared to placebo, diltiazem did not significantly change the overall dysphagia index and chest pain index. An individual sizeable reduction of dysphagia was attained on diltiazem in four out of six patients and in six out of eight patients suffering from chestpain. Side effects were not seen during diltiazem therapy. Diltiazem, in our study, did not yield in a significant improvement of symptoms in diffuse oesophageal spasm. Diltiazem, however, can offer relief in selected individual patients suffering from diffuse oesophageal spasm.  相似文献   
990.
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