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31.
The efficacy of intravenous thrombolytic agents in preserving left ventricular function and in decreasing mortality from an acute myocardial infarction was demonstrated in the 1980s. The 1990s will concentrate on adjunctive therapy to thrombolysis in the treatment of an acute myocardial infarction. 相似文献
32.
33.
Plasma levels and vascular effects of vasopressin in patients undergoing coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Susana Novella Ana Cristina Martínez Rosa María Pagán Medardo Hernández Albino García-Sacristán Angel González-Pinto José María González-Santos Sara Benedito 《European journal of cardio-thoracic surgery》2007,32(1):69-76
OBJECTIVE: Recent studies have suggested that endogenous vasopressin (AVP) acts as a spasmogen during coronary artery bypass grafting (CABG). Given that AVP could induce vasospasm in the grafted vessel, we assessed the release of this peptide during and after CABG, and explored ways of counteracting its contractile effect on the internal mammary artery (IMA). METHODS: Plasma levels of AVP were determined by radioimmunoassay in 16 patients before, during and after CABG. Using isometric force recording techniques, we also investigated the mechanisms involved in the contractile effect of AVP in ring preparations of IMA specimens taken from 95 patients. RESULTS: Plasma AVP levels peaked after the start of cardiopulmonary bypass (CPB) and correlated well with serum osmolality (Pearson's r=0.9490; P<0.0001; n=16). An inverse correlation was observed between plasma AVP levels recorded at this stage and the maximal contraction induced in vitro by AVP in vascular rings from the same patients (Pearson's r=-0.6968; P<0.01; n=16). No change in the AVP response was produced by endothelium removal, exposure to the NO precursor (3 x 10(-4)M L-arginine), inhibition of nitric oxide (NO) synthase (3 x 10(-5) M L-NAME) or soluble guanylate cyclase (3 x 10(-6) M 1H-[1,2,4]oxadiazol [4,3,-alpha]quinoxalin-1-one (ODQ)), removal of the superoxide anion (100 U/ml superoxide dismutase (SOD) plus 1200 U/ml catalase) or hydroxyl radical (10(-4) M deferoxamine), or specific alpha1 - (10(-6) M prazosin) or endothelin (10(-5) M bosentan) receptor antagonism. In contrast, adenylate cyclase activation (3 x 10(-8) M forskolin) reduced the contractile response to AVP, while prostanoid synthesis (3 x 10(-6) M indomethacin) inhibition and blockade of Ca2+ -activated potassium channels (KCa) (10(-3) M tetraethylammonium (TEA)) enhanced AVP contraction. Age, gender and smoking also modified the AVP response. CONCLUSION: Our findings suggest a role for AVP as a modulator of vascular tone in human IMA. The effect of AVP is dependent on prostanoids and Ca2+ -activated K+ channels, so its dysfunction in pathophysiological cardiovascular processes could mean that AVP, among other factors, produces vasospasm in IMA grafts. 相似文献
34.
Summary Three species of digeneans including 1 Gorgoderidae (Plesiochorus cymbiformis) from the urinary bladder, 1 Plagiorchiidae (Enodiotrema megachondrus) from the duodenum, and 1 Pachypsolidae (Pachypsolus irroratus) from the stomach were recovered from 2 of 3 olive ridley turtles (Lepidochelys olivacea) found stranded along the Pacific coast of Costa Rica. All trematodes represent new locality records. Histopathological changes
associated with eggs of cardiovascular flukes (Digenea, Spirorchiidae) were described from the lungs, spleen, and intestine
of a single turtle. 相似文献
35.
36.
E Moreno González I Landa Garcia J Calleja Kempin M Gomez Gutierrez J Arias Diaz D Riano Carrera F Parez Cerda P Moral Gutierrez F Guillen Ramirez I Garcia Garcia 《Der Chirurg》1990,61(10):701-704
Between 4/1986 to 1/1989, 74 orthotopic liver transplantation were performed in 62 patients (62 first liver transplants, 10 as second graft and two as a third graft); 57 in adults and 17 in children. The main indication for the operation was liver cirrhosis (61.4%) (the most frequent etiology was alcoholic cirrhosis, 28.5%). Six cirrhotic patients had a hepatocarcinoma (9.6%). Two received a liver and kidney transplant due to terminal renal insufficiency and hemodialysis. The most frequent indication in children was biliary atresia (33.3%). Six patients had a fulminal liver failure (9.6%). AB0 blood group compatibility was identical in 87.5%, compatible in six and incompatible in three patients. Total orthotopic liver transplantation was performed in 67 patients, and size-reduced liver was indicated in 7 patients. Extracorporeal veno-venous bypass was used in adults but never in children. In 93.1% of the transplants a single hepatic artery was anastomosed to the recipient and in 6.9% a double anastomosis was performed. In 62.5% of the patients a end-to-end choledocho-choledochostomy was performed and in 34.8% hepatico-jejunostomy was indicated. Three months postoperative mortality rate was 12.9%. Arterial stenosis and thrombosis were the most frequent complication. 相似文献
37.
To evaluate the effects of irradiation on heterotopically placed vascularized knee isografts, a single dose of 10 Gy of total-body irradiation was given to Lewis donor rats. Irradiation was delivered either 2 or 6 days prior to harvesting or subsequent transplantation, and evaluated at 1, 2, and 4 weeks after grafting. Irradiation caused endothelial depopulation of the graft artery, although vascular pedicle patency was maintained throughout the study. Bone graft viability and mineralization were normal. Dramatic changes in the bone marrow were seen that included an increase of its fat content (P less than 0.001), and a concomitant decrease in bone marrow-derived immunocompetent cells. These changes were more prominent in recipients of grafts from day -6 irradiated donor rats. Total-body irradiation did not prejudice the use of vascularized bone grafts, and exhibited an associated immunosuppresant effect over the vascular endothelium and bone marrow. This may be a further rational conditioning procedure to avoid recipient manipulation in vascularized bone allotransplantation. 相似文献
38.
Minorities and AIDS: knowledge, attitudes, and misconceptions among black and Latino adolescents. 总被引:4,自引:2,他引:2
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White adolescents in San Francisco high schools were more knowledgeable than Black adolescents about the cause, transmission, and prevention of AIDS (acquired immunodeficiency syndrome), and Black adolescents were more knowledgeable than their Latino peers. Black and Latino adolescents were approximately twice as likely as White adolescents to have misconceptions about the casual transmission of AIDS. Less knowledge about AIDS and prevalent misconceptions were associated with greater levels of perceived risk of contracting AIDS. 相似文献
39.
40.
The surgical treatment of rectal cancer of the middle third remains controversial. We treated 30 consecutive patients with preoperative radiotherapy (45 Gy) and low anterior resection. Anastomoses were performed with a stapler. Intraoperative frozen-section examination of the rectal margin established that it was free of tumor. Two patients died of surgery-related causes. Median follow-up of the remaining patients is now 52 months (range: 26 to 76 months). Eight patients had recurrences documented at surgical re-exploration: two local (pelvic) only, three local and distant, and two distant only. Local recurrences happened despite a frozen-section examination of the rectal margin negative for tumor. Six of the eight patients who experienced a recurrence have died of disease progression. Distant metastases were found in six other patients during follow-up; they subsequently died. Thus, our therapeutic approach was not associated with decreases in local or overall recurrences. 相似文献