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31.
Effect of conjugated estrogens on platelet function and prostacyclin generation in CRF 总被引:2,自引:0,他引:2
M Heistinger F Stockenhuber B Schneider I Pabinger B Brenner B Wagner P Balcke K Lechner P A Kyrle 《Kidney international》1990,38(6):1181-1186
In a double-blind, randomized, placebo-controlled cross-over study, we investigated in seven patients with chronic renal failure the effect of conjugated estrogens (0.6 mg/kg/day for 5 days) on template bleeding time and on thromboxane A2 (TxA2), beta-thromboglobulin (beta-TG) and prostacyclin (PGI2) concentrations in blood emerging from the template bleeding time incisions. Administration of conjugated estrogens resulted in a significant shortening of the bleeding time in six out of seven patients with a maximum effect 7 and/or 14 days following treatment. Both TxA2 (measured as thromboxane B2, TxB2) and beta-TG release in bleeding time blood were significantly higher following administration of conjugated estrogens as compared to placebo administration. No difference was seen in endothelial PGI2 (measured as 6-keto-prostaglandin F1 alpha) formation when patients were treated with conjugated estrogens as compared to placebo administration over the 28 day observation period. We conclude that in patients with chronic renal failure, infusion of conjugated estrogens results in a significant shortening of the bleeding time together with an increase in platelet reactivity, as indicated by an increase of TxA2 and beta-TG concentration in the microvasculature. No effect was seen on PGI2 production, thereby excluding a major effect on vascular prostaglandin metabolism. 相似文献
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33.
J T Johnson R L Wagner D E Schuller J Gluckman J Y Suen N L Snyderman 《Archives of otolaryngology--head & neck surgery》1992,118(5):488-490
The leading cause of postoperative morbidity in patients undergoing major head and neck surgical procedures is postoperative infection. This prospective randomized multi-institutional clinical trial was designed to compare the effectiveness of clindamycin phosphate and high-dose cefazolin sodium therapy in preventing postoperative wound sepsis in patients undergoing contaminated head and neck surgical procedures in which flap reconstruction was required. Either clindamycin phosphate (900 mg) or cefazolin sodium (2 g) therapy was instituted intravenously prior to surgery and continued every 8 hours, for a total of 24 hours. The patients received postoperative follow-up, and the wounds were graded according to the worst condition observed. One hundred cases were evaluated. Fifty-one patients received clindamycin and 49 patients received high doses of cefazolin; wound infection developed in 10 patients (19.6%) and 11 patients (21.6%), respectively. This difference was not statistically significant. The average duration of surgery was approximately 8 hours for both the infected and the noninfected groups of patients. High-dose cefazolin and clindamycin have similar efficacy when administered prophylactically under these circumstances. Reconstruction with free vascularized tissue may aid in reducing postoperative wound infection. 相似文献
34.
A 6 1/2-year-old white male child had developed bilateral dacryocystitis 1 year earlier, approximately 6 months after resolution of the acute phase of Kawasaki's disease. The patient had had no previous history of dacryostenosis or epiphora. After he failed to respond to appropriate antibiotic therapy, probing was partially successful on the right side, but complete obstruction persisted on the left side. At age 7 1/2 years, dacryocystorhinostomy was performed successfully on the left side. To our knowledge, dacryocystitis has not been reported previously following Kawasaki's disease. Other reported ocular complications of Kawasaki's disease, with the exception of a case of bilateral conjunctival scarring, have occurred in the acute phase of the disease. 相似文献
35.
D J Ballard D S Strogatz E H Wagner D S Siscovick S A James D G Kleinbaum C A Williams L M Cutchin M A Ibrahim 《American journal of preventive medicine》1986,2(5):278-284
As part of the Edgecombe County High Blood Pressure Control Program, a medical record review was conducted within a multispecialty private group practice in the county. The purposes of the review were to assess the relationship between the process of medical care and blood pressure control and to explore the variation in level and impact of medical care by race and sex. At the end of a three-year period, 41 percent of 628 hypertensive patients from the practice had uncontrolled diastolic blood pressure (DBP), as defined by Hypertension Detection and Follow-up Program criteria. The percentage of uncontrolled hypertensives ranged from 53 percent for black men to 34 percent for white women. Hypertensive patients whose physicians were more aggressive in their use of antihypertensive drug therapy were more likely to be controlled. The effect of the level of physician drug aggressiveness tended to be more pronounced for blacks than for whites. Differences by race in exposure to and efficacy of aggressive drug treatment may influence racial variation in blood pressure control. 相似文献
36.
Phrenic and cervical sympathetic nerve responses to hypercapnia were examined before and after anesthesia in twelve midcollicularly decerebrated, vagotomized, glomectomized, paralyzed and ventilated cats. We measured responses of integrated phrenic and cervical sympathetic nerve activities to increases in end-tidal PCO2 (PETCO2) from apneic threshold to approximately 30 torr above threshold. All cats were studied first in the unanesthetized state. Six cats were then restudied after a quarter of a usual dose of chloralose/urethane (10 mg/kg and 62.5 mg/kg, respectively) and then after half the usual dose of chloralose/urethane (20 mg/kg and 125 mg/kg). The other six animals were restudied after quarter of a standard dose of pentobarbital (9 mg/kg), after half the standard dose (18 mg/kg) and then after the full (35 mg/kg) dose. Both anesthetic agents led to significant increases in apneic thresholds for both phrenic and sympathetic nerve activities. These agents also caused dose-dependent decreases in peak, tonic and respiratory-related sympathetic nerve activities. Peak (tidal) phrenic nerve activities, in comparison, were much less affected by the anesthetic agents. CO2 response curves showed that both of these anesthetic agents depressed, at any given level of PETCO2, respiratory-related sympathetic nerve responses more than the responses found in the phrenic nerve. We conclude that the relations between peak, tonic (i.e. between phasic bursts) and respiratory-related sympathetic nerve activities and phrenic nerve activity can be altered by anesthesia. 相似文献
37.
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39.
Evaluation of intrinsic and extrinsic motivation interventions with a self-help smoking cessation program 总被引:8,自引:0,他引:8
Personalized feedback and a financial incentive, developed from an intrinsic/extrinsic motivation framework, were evaluated as adjuncts to self-help materials for smoking cessation. Ss (N = 1,217) were randomized to 4 treatment groups and were followed up at 3 and 12 months. Consistent with hypotheses derived from the motivation framework, the financial incentive increased the use of self-help materials, did not increase cessation rates among program users, and was associated with higher relapse rates among those who did manage to quit. The personalized feedback increased both smoking cessation and use of the materials 3 months after distribution of the materials. Continuous abstinence (abstinence at 3 and 12 months) in the group that received the personalized feedback alone was twice the rate of the other groups. 相似文献
40.
With increasing numbers of primary anterior cruciate ligament reconstruction, the incidence of unsatisfactory results and graft failures will increase. The goals of revision reconstruction are similar to those of primary reconstruction and include stabilization of the knee, prevention of secondary degenerative changes, and recovery of knee function. Besides the recurrent tear there are specific technical failures, such as tunnel malplacement and unrecognized associated ligamentous pathologies, which might lead to graft failure. Thus, preoperative planning includes a detailed analysis of failure mechanisms by thorough preoperative history taking, comprehensive physical examination, and appropriate radiographic evaluation. The treatment algorithm addresses issues of hardware removal, need for a staged procedure or concomitant surgery, graft source, tunnel placement, and graft fixation. Correct placement of tunnels and graft fixation are the essential surgical steps, which might also influence graft selection. Successful revision ACL surgery requires a motivated and compliant patient and an experienced surgeon who is proficient in a variety of different surgical techniques. However, since clinical outcome is reported to be inferior in revision compared to primary ACL reconstruction the importance of counseling the patient preoperatively regarding less satisfactory results than in most primary ACL reconstructions must be emphasized. This article describes indications, analysis and surgical procedures for revision anterior cruciate ligament reconstruction. 相似文献