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101.
Pure autonomic failure is characterized by orthostatic hypotension, sweating disorder, urinary incontinence, and syncope. A 64 year-old man with pure autonomia failure was scheduled for suprapubic prostatectomy. We monitoring direct arterial pressure and inserted pulmonary artery catheter prior to the induction of anesthesia. General anesthesia was induced with diazepam 10 mg, fentanyl 0.3 mg, and vecuronium 8 mg for tracheal intubation. Anesthesia was maintained with sevoflurane (0.2-1.5%), 60% nitrous oxide in oxygen supplemented with intermittent epidural anesthesia. During anesthesia, blood loss was immediately replaced with banked blood because autonomic failure could not compensate hypovolemia well. Epidural anesthesia in this patient was considered to cause less hypotension than in patients with normal autonomic function. Therefore, we think epidural anesthesia is a useful anesthesia method for patients with pure autonomic failure. The emergence from anesthesia was smooth and no complications were seen during the perioperative period.  相似文献   
102.
BACKGROUND: Vesnarinone, an inotropic drug, was shown in a short-term placebo-controlled trial to improve survival markedly in patients with severe heart failure when given at a dose of 60 mg per day, but there was a trend toward an adverse effect on survival when the dose was 120 mg per day. In a longer-term study, we evaluated the effects of daily doses of 60 mg or 30 mg of vesnarinone, as compared with placebo, on mortality and morbidity. METHODS: We enrolled 3833 patients who had symptoms of New York Heart Association class III or IV heart failure and a left ventricular ejection fraction of 30 percent or less despite optimal treatment. The mean follow-up was 286 days. RESULTS: There were significantly fewer deaths in the placebo group (242 deaths, or 18.9 percent) than in the 60-mg vesnarinone group (292 deaths, or 22.9 percent) and longer survival (P=0.02). The increase in mortality with vesnarinone was attributed to an increase in sudden death, presumed to be due to arrhythmia. The quality of life had improved significantly more in the 60-mg vesnarinone group than in the placebo group at 8 weeks (P<0.001) and 16 weeks (P=0.003) after randomization. Trends in mortality and in measures of the quality of life in the 30-mg vesnarinone group were similar to those in the 60-mg group but not significantly different from those in the placebo group. Agranulocytosis occurred in 1.2 percent of the patients given 60 mg of vesnarinone per day and 0.2 percent of those given 30 mg of vesnarinone. CONCLUSIONS: Vesnarinone is associated with a dose-dependent increase in mortality among patients with severe heart failure, an increase that is probably related to an increase in deaths due to arrhythmia. A short-term benefit in terms of the quality of life raises issues about the appropriate therapeutic goal in treating heart failure.  相似文献   
103.
104.
OBJECTIVE: To determine the clinical and microbiologic benefit of adding amikacin to a four-drug oral regimen for treatment of disseminated Mycobacterium avium infection in HIV-infected patients. DESIGN: A randomized, open-labeled, comparative trial. SETTING: Outpatient clinics. PATIENTS: Seventy-four patients with HIV and symptomatic bacteremic M. avium infection. INTERVENTIONS: Rifampin 10 mg/kg daily, ciprofloxacin 500 mg twice daily, clofazimine 100 mg every day, and ethambutol 15 mg/kg orally daily for 24 weeks, with or without amikacin 10 mg/kg intravenously or intramuscularly 5 days weekly for the first 4 weeks. MAIN OUTCOME MEASURE: Clinical and microbiologic response at 4 weeks; quantitative level of bacteremia with M. avium. RESULTS: No difference in clinical response was noted with the addition of amikacin to the four-drug oral regimen, and only 25% in either group had a complete or partial response at 4 weeks. A comparable quantitative decrease in bacteremia was noted in both treatment groups, with 16% of patients being culture-negative at 4 weeks and 38% at 12 weeks. Toxicities were mainly gastrointestinal. Amikacin was well tolerated. Median survival was 30 weeks in both groups. CONCLUSIONS: The addition of amikacin to a four-drug oral regimen of rifampin, ciprofloxacin, clofazimine, and ethambutol did not provide clinical or microbiologic benefit.  相似文献   
105.
BACKGROUND: There is increasing use of highly sensitive testing with polymerase chain reaction (PCR) to study white cell microchimerism after transfusion and transplantation. This study investigated possible artifactual sources of allogeneic sample contamination before PCR testing. STUDY DESIGN AND METHODS: Quantitative Y-chromosome PCR was used to study microchimerism among transfused patients with sickle cell disease (SCD) and thalassemia by using residual specimens from the clinical laboratory. High levels of circulating male white cells among transfused patients with SCD but not thalassemia led to concern over the artifactual origin of male cells. To investigate, paired specimens were collected from 26 female SCD patients: one specimen underwent processing only for PCR, while the other underwent testing in the clinical laboratory before PCR as a process control. All laboratory instruments were also assessed for their ability to impart male allogeneic cells to aliquots of female blood. RESULTS: Thirty-three (31%) of 107 SCD samples, but 0 of 20 thalassemia samples, gave a high-level PCR signal. One of 26 paired samples that was not exposed to clinical laboratory equipment had low-level PCR positivity while 10 of the 26 became strongly positive after testing on a blood cell analyzer and a reticulocyte analyzer. Sixteen of 32 female samples became positive after reticulocyte analysis, while none became positive after blood cell analysis. Samples from thalassemia patients tested PCR-negative because reticulocyte counts had not been performed. CONCLUSION: Allogeneic cell contamination is common with clinical laboratory equipment. These samples may not be suitable for microchimerism studies. In addition to method controls, process controls should be employed where appropriate.  相似文献   
106.
The effect of 6 weeks' streptozotocin (STZ)-induced (70 mg/kg) diabetes and aminoguanidine (AG) treatment (50 mg/kg s.c. or 250-750 mg/l given in drinking water) on arteriolar reactivity to vasoactive substances was investigated in conscious rats. Studies were performed in untreated control rats (n = 13), STZ-induced diabetic rats (n = 11), AG-treated control rats (n = 12), and AG-treated diabetic rats (n = 12). Rats were provided with a dorsal microcirculatory chamber that allowed intravital microscopy of striated muscle arterioles of varying diameter (A1, large; A2, intermediate; and A3, small arterioles) in conscious animals. The mean arterial pressure (MAP) and arteriolar diameter responses to intravenous infusion of the following drugs were examined: the endothelium-dependent vasodilator acetylcholine (ACh; 3, 10, and 30 microg x kg(-1) x min(-1)), the potassium-channel opener levcromakalim (LC; 30 microg/kg), and the vasoconstrictor agents ANG II (0.1 and 0.3 microg x kg(-1) x min(-1)) and norepinephrine (NE; 0.2, 0.6, and 2.0 microg x kg(-1) x min(-1)). Baseline MAP was lower in both diabetic groups versus the nondiabetic groups (P < 0.05). AG treatment had no influence on baseline MAP. The absolute change in MAP after drug infusion tended to be lower in the diabetic rats than in their nondiabetic littermates. Arteriolar vasodilatory responses to ACh and LC were attenuated in the diabetic animals (1 +/- 7 vs. 19 +/- 7% [P < 0.05] and 7 +/- 3 vs. 34 +/- 8% [P < 0.01] in A2, respectively). AG treatment of diabetic animals did not prevent the development of this disturbance. Vasoconstrictor responses were not influenced by the diabetic state. In the intermediate arterioles of AG-treated control rats, a hyperresponse was observed after ANG II infusion (-10 +/- 2 vs. -2 +/- 2%; P < 0.05) and a hyporesponse was observed after ACh and LC infusion (2 +/- 3 and 15 +/- 6%, respectively; P < 0.05 vs. untreated control rats). These data indicate that 6 weeks of experimental diabetes is associated with a decreased endothelium-dependent and -independent vasodilatation. AG treatment had no beneficial effect on this disturbance.  相似文献   
107.
5 experiments investigated children's understanding that expectations based on prior experience may influence a person's interpretation of ambiguous visual information. In Experiment 1, 4- and 5-year-olds were asked to infer a puppet's interpretation of a small, ambiguous portion of a line drawing after the puppet had been led to have an erroneous expectation about the drawing's identity. Children of both ages failed to ascribe to the puppet an interpretation consistent with the puppet's expectation. Instead, children attributed complete knowledge of the drawing to the puppet. In Experiment 2, the task was modified to reduce memory demands, but 4- and 5-year-olds continued to overlook the puppet's prior expectations when asked to infer the puppet's interpretation of an ambiguous scene. 6-year-olds responded correctly. In Experiment 3, 4- and 5-year-olds correctly reported that an observer who saw a restricted view would not know what was in the drawing, but children did not realize that the observer's interpretation might be mistaken. Experiments 4 and 5 explored the possibility that children's errors reflect difficulty inhibiting their own knowledge when responding. The results are taken as evidence that understanding of interpretation begins at approximately age 6 years.  相似文献   
108.
There are many questions and no clear answers raised by these children. These syndromes, however, seem to be biologic experiments of nature and present unique opportunities to study the various elements involved in the pathogenesis of arthritis. Pediatric rheumatologists are in a unique position to study these syndromes.  相似文献   
109.
"Odin是仅有的一辆全面应用LabVIEW的赛车,并且取得了第三名的成绩,仅比领先者慢了几分钟。"DARPA城市挑战赛要求路上车辆在城市环境中无人驾驶行驶。在整个赛程中,全自主的无人车要在不到6小时中行驶60英里,并在道路、十字路口、停车场等交通环境里行驶。比赛开始时,一份任务文档规定了比赛道路  相似文献   
110.
A study of six brands of silicate of soda used in a typical ceramic casting slip discloses the effect of the Na2O to SiO2 ratio on hydrometer readings, pH, viscosity, casting rate, water retention, drying shrinkage, dry strength, firing shrinkage, fired strength, and fired absorption. The effect of varying the amount of electrolyte both above and below that required for complete deflocculation is also reported.  相似文献   
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