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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
G L Hines Y Mishriki L Williams K Monroe N Metwally 《The Journal of cardiovascular surgery》1991,32(4):485-490
This study attempted to evaluate the efficacy of chronic extra-aortic counterpulsation with a latissimus dorsi neuro vascular flap. Five dogs had a preliminary procedure consisting of the creation of a latissimus dorsi flap and a thoracotomy in which the flap was wrapped around the descending aorta just distal to the left subclavian artery. An epicardial lead was placed on the left ventricle and a nerve stimulating lead placed around the thoraco-dorsal nerve. Three weeks later, both leads were connected to a cardiomyostimulator programmed to function in a counterpulsation mode with a 1:2 assist frequency. Hemodynamic measurements were made at 6 and 8 and 10 and 12 weeks and the dogs were sacrificed. Three dogs had all sets of hemodynamic measurements made. Two of the three dogs demonstrated diastolic augmentation at 6 and 8 and 10 and 12 weeks average 20 to 25 mmHg. The third dog failed to demonstrate any change. All dogs were sacrificed at 12 weeks and specimens were submitted for histologic evaluation. The muscle flap was preserved in all animals. The aorta subjacent to the flap showed, (1) normal intima with no evidence of disruption or thrombus in all animals, (2) in the animals in whom counterpulsation was observed, there appeared to be thinning of the media in the aorta subjacent to the muscle flap, and (3) no evidence of distal emboli. This study demonstrated that chronic counterpulsation can be obtained with a latissimus dorsi flap. The actual hemodynamic benefits are not determined from this study. The medial thinning in the aortic wall may limit the long-term benefit of this procedure. 相似文献
982.
Fluconazole resistance in AIDS patients. 总被引:14,自引:0,他引:14
983.
The purpose of this study was to correlate histologic findings in temporomandibular joint (TMJ) condyles and discs with their macroscopic appearance at surgery. The 24 patients with internal derangement of the joint included 20 women and 4 men (mean age, 37 years; range, 18 to 61 years). The tissue lesions varied in degree from mild soft-tissue fraying and bone remodeling to extensive resorption and new cartilage and bone formation with high phosphatase enzyme activities, and even to loss of articular soft tissue and breakdown of cortical bone. Reactions may arise in the hard tissues before they occur in the articular surface layers. 相似文献
985.
Twenty patients with sympathetic maintained pain (SMP) underwent surgery to treat an associated nerve injury. In each patient, an axillary catheter technique was used to maintain anesthesia and sympatholysis for up to 4 days following surgery. In no instance was the SMP exacerbated by the operation. The use of prolonged sympathetic blockade as an adjunct increases the margin of safety in surgery for these patients when nonoperative measures cannot relieve the pain or restore function. 相似文献
986.
Angiolymphoid hyperplasia with eosinophilia of the orbit associated with obstructive airway disease 总被引:2,自引:0,他引:2
Two patients with angiolymphoid hyperplasia with eosinophilia isolated to the orbit had eyelid swelling, a superior orbital mass, and histories of intermittent obstructive airway disease. One patient later developed a transient peripheral blood eosinophilia as high as 36%. One lesion recurred 38 months postoperatively and responded to systemic corticosteroid therapy. 相似文献
987.
B M Cohen G Stramentinoli A L Sosa S M Babb V Olgiati 《European journal of pharmacology》1989,170(3):201-207
alpha 1- and beta-adrenoceptors were studied ex vivo in the brains of rats receiving repeated daily treatment with the standard antidepressant imipramine or the atypical antidepressant S-adenosyl-L-methionine (SAM), which has minimal effects on monoamine reuptake or turnover. Consistent with past studies, a decrease in the density of beta receptors at three weeks and an increase in the affinity of alpha 1 receptors for the agonist phenylephrine at one week of treatment was observed with imipramine. By comparison, an increase in the density of beta receptors and a decrease in the affinity of alpha 1 receptors for phenylephrine was observed at one week of treatment with SAM. These changes were no longer apparent at three weeks of treatment. The results suggest that treatment with SAM does lead to changes in adrenergic neurotransmission, but that down regulation of beta receptors or increased agonist affinity of alpha 1 receptors may not be necessary for the production of antidepressant effects. 相似文献
988.
989.
The authors describe a very rare case of choreoathetotic movements which appeared in an epileptic in strict relationship to a toxic concentration of diphenylhydantoin in the serum. These movements were reversible and disappeared after reduction of drug dose and its serum concentration falling to the therapeutic range. 相似文献
990.