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991.
In 19 pregnancies at risk for 21-hydroxylase deficiency (21OHD) in 18 families with at least one affected child, prenatal diagnosis was performed by RFLP analysis using the enzymes Taq I and EcoRI and the DNA probes specific for the 21OH genes, the closely linked complement C4 genes and the highly polymorphic HLA class II genes DRB, DQB, and DPB. For fetal DNA analysis either chorionic villi or cultivated amniotic cells were used. In all 19 cases, a clear prenatal diagnosis was possible either with the 21OH probe alone or in most cases, by combining the results of the different closely linked loci. 相似文献
992.
营养药理学--谷氨酰胺、n-3脂肪酸和精氨酸等简介 总被引:5,自引:2,他引:3
引言营养不良总是影响外科患者的预后,20世纪初就有人注意到伴有营养不良(以体重降低20%为依据)的消化性溃疡患者术后恢复较慢。后来几十年的研究证明,特殊营养素(如某些维生素和矿物质)缺乏能导致疾病,给予补充则可恢复健康。近年来研究发现,低蛋白血症等营养不良指标与并发症的发生率和死亡率相关。20世纪60年代至70年代的研究表明,对于严重烧伤儿童,只增加营养素(蛋白)的相对浓度而不增加总热卡摄入,可纠正免疫功能低下,提高生存率,改善患儿预后。谷氨酰胺、n-3脂肪酸和精氨酸对疾病的影响引起人们的特别关注,许多学者致力于研究这些营养… 相似文献
993.
BACKGROUND. This prospective study was designed to test the hypothesis that the assessment of left ventricular systolic function at the time of emergency room (ER) presentation provides valuable diagnostic and prognostic information in patients with cardiac-related symptoms. METHODS AND RESULTS. The study is based on a 2-year follow-up of 171 consecutive patients evaluated in the ER for such symptoms. In the course of follow-up, one third of the patients (55 of 171) suffered a major cardiac event. For those with left ventricular systolic dysfunction (LVSD), the age-adjusted rate of early events (occurring within 48 hours of presentation) was more than eight times higher than for those without LVSD (26.9% versus 3.3%, p less than 0.01). For events occurring after 48 hours of ER presentation, LVSD was associated with a nearly fourfold excess of cardiac events (23.9% versus 6.4%, p less than 0.01). Other than advanced age, the most important confounder for early events included an abnormal electrocardiogram diagnostic for acute myocardial infarction. Confounders for late events included advanced age and a history of hypertension. LVSD on two-dimensional echocardiography (2DE) was the only finding associated with early and late events after controlling for other risk factors. In addition, the prediction of these events derived from the combination of historical, clinical, electrocardiographic, and 2DE findings was significantly improved when accounting for the presence or absence of LVSD (p less than 0.01). CONCLUSIONS. We conclude that the 2DE assessment of left ventricular systolic function provides valuable diagnostic and prognostic information in subjects presenting to the ER with cardiac-related symptoms. 相似文献
994.
Using in vivo microdialysis, this study attempted to determine whether a neurochemical predisposition to self-administer morphine could be identified. Extracellular levels of dopamine and its metabolites were measured bilaterally in the mesocorticolimbic and nigrostriatal systems of naive rats that were subsequently trained to self-administer morphine intravenously. There were several significant relationships between dopamine metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) levels and rates of morphine self-administration during both acquisition and asymptotic phases of testing. DOPAC and HVA levels in the striatum were inversely correlated with self-administration rates during the asymptotic phase whereas hemispheric asymmetries in striatal metabolite levels were inversely correlated with self-administration during the acquisition phase. DOPAC and HVA levels in in the right but not in the left side of the medial prefrontal cortex were positively correlated with self-administration rates during the acquisition phase; right/left asymmetries in cortical metabolite levels were also correlated with acquisition rates. There were no significant relationships between neurochemical indices and rates of bar-pressing for water. These results suggest that the normal variability in drug seeking behavior is at least in part attributable to individual differences in the organization and activity of brain dopamine systems. Furthermore, different mechanisms appear to be responsible for the initiation and maintenance of morphine intake: DA release in the nucleus accumbens appears to be a critical component of both mechanisms; DA release in the striatum appears to modulate maintenance and, in relationship to striatal lateralization, modulate initiation; DA release in the right but not in the left medial prefrontal cortex appears to be an important predictor of initiation. 相似文献
995.
This report describes injury to the hepatic artery with pseudoaneurysm formation and hemobilia following the use of laser-assisted dissection to perform laparoscopic cholecystectomy.A 57-year-old woman was referred emergently 2 weeks after laser laparoscopic cholecystectomy with upper abdominal pain, upper gastrointestinal bleeding, and jaundice. A selective hepatic arteriogram showed a right hepatic artery pseudoaneurysm which was embolized. Two weeks later the patient had recurrent hemobilia as the result of blood flow restoration in the pseudoaneurysm and a fistula to the cystic duct remnant. She was treated with two additional embolizations and direct injection of the aneurysm with thrombogenic material. Follow-up at 2 years showed no further recurrence.Since the laser has never been shown to have advantages over electrocautery, its use during laparoscopic cholecystectomy is difficult to justify.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), San Francisco, California, USA, October 1993 相似文献
996.
997.
Megestrol acetate in cancer anorexia and weight loss. 总被引:9,自引:0,他引:9
N S Tchekmedyian M Hickman J Siau F A Greco J Keller H Browder J Aisner 《Cancer》1992,69(5):1268-1274
High-dose megestrol acetate has been associated with increased appetite and weight. To examine the effects of high-dose megestrol acetate in the treatment of anorexia and weight loss in patients with advanced hormone-insensitive malignant lesions, a randomized double-blind placebo-controlled trial was conducted. Patients receiving megestrol acetate for 1 month reported a significant improvement in appetite and adequacy of food intake compared with those receiving placebo. A three-item scale measuring appetite, adequacy of food intake, and concern about weight revealed a higher improvement with megestrol acetate than with placebo. Patients who worsened while receiving placebo had similar favorable changes after the cross over to megestrol acetate. These data indicate that megestrol acetate may improve appetite and food intake in patients with advanced cancer. 相似文献
998.
999.
Recreational use of cocaine dates back to the Incas in South America 5000 years ago. Cocaine is derived from the leaves of Erythroxylon coca, a shrub native to South America. In the late 1800s, Sigmund Freud popularized the drug in Europe. He used cocaine to treat depression, asthma, cachexia, and for overcoming morphine addiction. Also in this period cocaine rapidly gained acceptance in surgical procedures as a local anesthetic and vasoconstrictor. Cocaine reached the United States in the early 1900s, and its popularity led President Taft to declare it public enemy number one in 1910. Cocaine became popular again in the 1980s. Currently cocaine use is responsible for more ED visits then any of the other illicit drugs. Because most cocaine users are young, they are at a lower risk for coronary artery atherosclerotic disease. An estimated 25 million people between the ages of 26 and 34 years have used cocaine at least once, 20% were women and 30% men. Habitual users of cocaine are estimated to number 1.5 million. Most cocaine-induced chest pains do not progress to MI, and in fact many originate in the chest wall. The chest pains due to cocaine, however, are induced by myocardial ischemia, a result of vasospasm and not a thrombotic occlusion of a coronary artery that has a ruptured atheromatous plaque. ECG findings can be misleading in the diagnosis because the early repolarization syndrome, a normal variant, is a frequent finding in young African American men. Measurement of cardiac troponin levels is the most reliable diagnostic test. Percutaneous coronary intervention and angioplasty, rather than thrombolysis, is the treatment of choice because intense coronary vasospasm is the primary pathophysiology in cocaine-induced MI. 相似文献
1000.
The ability of Adriamycin (AD) to enhance the known in vitro and in vivo tumoricidal effects of photodynamic therapy (PDT) on the H-MESO-1 human malignant mesothelioma cell line was investigated. In vitro cytotoxicity was determined by incubating H-MESO-1 cells in microtiter plates (2 x 10(5) cells/well, 6 wells/group) with the photosensitizer Photofrin II (PF) and varying concentrations of AD (0, 2.5, 5.0, and 10.0 micrograms/ml) for 24 hr followed by exposure to gold vapor laser light (GVL) at a fluence of 6000 J/M2. [3H]Thymidine (1 microCi) was added to each well 24 hr after treatment. Cells were harvested and counted for thymidine incorporation 24 hr later. PDT alone resulted in a decrease in thymidine incorporation of 23% while the addition of AD to PDT at AD concentrations of 2.5, 5.0, and 10.0 micrograms/ml resulted in decreases of 62, 85, and 69%, respectively (P = 0.005) as compared to untreated controls. H-MESO-1 tumor bearing nude mice (n = 5) were injected ip with PF (5 mg/kg) and AD (5 mg/kg) 24 hr prior to illumination of the tumor site with GVL (120 J/cm2). Control groups (n = 5) received PDT, AD, and/or GVL alone. Tumor surface area was measured as the product of the greatest perpendicular dimensions every 5 days for 30 days. Administration of PDT without AD resulted in a decrease in tumor surface area of 50% on Day 10 with regrowth of tumor by Day 30 while AD alone with or without GVL had no impact on tumor growth.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献