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排序方式: 共有2152条查询结果,搜索用时 15 毫秒
991.
M Knauth CR Wirtz VM Tronnier A Staubert S Kunze K Sartor 《Canadian Metallurgical Quarterly》1998,38(3):218-224
The outcome of 703 patients who underwent surgery following aneurysmal subarachnoid hemorrhage were analyzed with regards to age, associated medical conditions, vasospasm and clinical status at the time of operation. Patients with Hunt and Hess grade I, II, and III had a 96%, 90% and 93% favorable (good and fair) outcome respectively. In contrast only 58% of patients with grade IV had the same result. The outcome was unfavorable in 13% of the patients who were older than 60 years of age and only in 9% of the patients between 30-59 years of age. All the patients younger than 30 years old had a good outcome. Associated medical condition increased the incidences of poor outcome (7% vs. 12%). Patients harboring vertebro basilar aneurysms had a poorer outcome, as opposed to those with aneurysms located in the anterior circulation (20% vs. 8%). The presence of angiographic vasospasm alone did not influence outcome. A proposed point value was given for each of the adverse factors and from this the optimal surgical time was determined for each individual patient. This concept of Risk Score Estimation approach may improve the management outcome of patients with ruptured intracranial aneurysms. 相似文献
992.
OBJECTIVES: The present study was conducted to compare pharmacokinetic behaviors of nicardipine enantiomers given in different doses with different formulations of racemic nicardipine in healthy volunteers. METHODS: One or two 20-mg racemic nicardipine tablets, and a 40-mg sustained-release capsule of nicardipine were administered to eight healthy volunteers in a crossover fashion and pharmacokinetic parameters were evaluated. Enantiomer concentrations were determined by GC-MS combined with chiral stationary phase HPLC. RESULTS AND CONCLUSIONS: Serum concentration of (+)-nicardipine was approximately 2-3 times higher than that of (-)-nicardipine in 20- and 40-mg doses of conventional formulations and a non-linear increase in bioavailability with dose was demonstrated. The value for AUC of (+)-nicardipine was approximately 2.3-2.8 times greater than that of the (-)-nicardipine (P < 0.05) when 20 and 40 mg racemic nicardipine were administered in a conventional preparation. Relative bioavailability of the sustained-release preparation vs the conventional preparation was 28% and 44% for (+)- and (-)-nicardipine, respectively, for the 40-mg dose. 相似文献
993.
BM Cheung R Leung S Shiu KC Tan CP Lau CR Kumana 《Canadian Metallurgical Quarterly》1998,16(8):1137-1140
OBJECTIVES: To compare the distributions of the genotypes and alleles of the M235T polymorphism of the angiotensinogen gene for hypertensive patients and normotensive controls. DESIGN: A study of association of genetic polymorphisms. SETTING: An outpatient clinic run by a university department handling referrals from primary care. PATIENTS: Two hundred and four subjects, 103 normal controls and 101 patients with newly diagnosed or documented hypertension. METHOD: Genomic DNA was extracted from peripheral blood leucocytes, amplified by polymerase chain reaction and digested with the restriction enzyme Tth 111 I. Methionine (M) and threonine (T) alleles were identified after electrophoresis. MAIN OUTCOME MEASURES: Prevalences of angiotensinogen genotypes and alleles for hypertensive patients and controls. Results: MM, TM and TT genotypes occurred in 3, 24 and 73% of controls and 1, 22 and 77% of hypertensive patients, respectively. The prevalences of the M and T alleles were 0.15 and 0.85 among controls and 0.12 and 0.88 among hypertensive patients. The prevalences of the angiotensinogen genotypes and alleles for controls and hypertensive patients did not differ significantly. CONCLUSIONS: Our findings differed from previous reports and suggested that this polymorphism is not associated with hypertension in this population. 相似文献
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999.
MA Wirth CM Agrawal JD Mabrey DD Dean CR Blanchard MA Miller CA Rockwood 《Canadian Metallurgical Quarterly》1999,81(1):29-37
OBJECTIVE: As anorectic and bulimic patients present similar clinical and neurobiological symptoms, the purpose of this study was to compare brain glucose metabolism at rest in these patients. METHODS: Positron emission tomography with (18-F)-fluorodeoxyglucose was used to evaluate cerebral glucose metabolism (CMRglu) in 10 normal-weight bulimic women, in 10 underweight anorectic patients, and in 10 age- and sex-matched healthy volunteers. RESULTS: Absolute global cortical glucose activity was significantly lower in anorectic patients compared with bulimic and control subjects. Anorectic patients compared with normal control subjects also showed higher relative CMRglu in the inferior frontal cortex and in the basal ganglia, and putamen and caudate relative hypermetabolism when compared with bulimic patients. Thus, both eating disorder groups differed from control subjects in low relative parietal values of glucose. DISCUSSION: While absolute global metabolism seems to be related to weight loss, we can hypothesize either a common parietal cortex dysfunction in eating disorders or a particular sensitivity of this cortex to consequences of eating disturbances. 相似文献
1000.
BACKGROUND: Compromised splanchnic perfusion and the resulting intestinal mucosal injury leads to a decreased mucosal barrier function, which allows translocation of intestinal flora and endotoxemia. The authors evaluated the effects of milrinone on splanchnic oxygenation, systemic inflammation, and the subsequent acute-phase response in patients undergoing coronary artery bypass grafting. METHODS: This open, placebo-controlled randomized clinical study enrolled 22 adult patients in two groups. Before induction of anesthesia, baseline values were obtained and patients were randomized to receive milrinone (30 microg/kg bolus administered progressively in 10 min, followed by a continuous infusion of 0.5 microg x kg(-1) x min(-1)) or saline. The following parameters were determined: hemodynamics; systemic oxygen delivery and uptake; arterial, mixed venous and hepatic venous oxygen saturation; intramucosal pH (pHi); and mixed and hepatic venous plasma concentrations of endotoxin, interleukin 6, serum amyloid A, and C-reactive protein. RESULTS: Milrinone did not prevent gastrointestinal acidosis as measured by pHi, but its perioperative administration resulted in significantly higher pHi levels compared with control. Venous and hepatic venous endotoxin and the interleukin 6 concentration were reduced significantly in the milrinone group. Serum amyloid A values were attenuated in the milrinone group 24 h after surgery. No significant differences could be seen in routinely measured oxygen transport-derived variables. CONCLUSIONS: Perioperative administration of low-dose milrinone may have antiinflammatory properties and may improve splanchnic perfusion in otherwise healthy patients undergoing routine coronary artery bypass grafting. 相似文献