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101.
A chiral poly(3-substituted isobutyl D -aspartate) 12 was synthesized by polymerization of the chiral β-lactam 11 derived from D -glyceraldehyde. The new polyamide was characterized by elemental analyses, and infrared, 1H- and 13C nuclear magnetic resonance spectroscopies. The molecular weight was estimated as 543 000 and 230 000 on the basis of viscosimetric measurements and gel-permeation chromatography, respectively. Polyamide 12 is soluble in a variety of organic solvents including chloroform.  相似文献   
102.
In order to investigate the efficacy of propafenone in the prevention of paroxysmal flutter or fibrillation, we treated 21 patients without left ventricular disfunction. Age was 60 +/- 14 (mean +/- sd) years, left atrial diameter by echocardiography 37 +/- 7 mm, cardiothoracic index 0.48 +/- 0.05 (0.41-0.57) and P wave duration 100 +/- 17 ms. The frequency of recurrences before treatment was: daily in five (23%), weekly or more in eight (38%), monthly-weekly in seven (33%) and quarterly-monthly in one (5%). Propafenone (671 +/- 187 mg/24 h) was given after recurrences were demonstrated under treatment with 1-3 antiarrhythmic drugs per patient. During 8.9 +/- 3.5 months of follow-up (range 6-19) 5 patients (23%) were completely free of recurrences; in seven (33%) the incidence decreased by greater than 50% with a marked decrease in duration. Side effects appeared in 12 cases (57%), leading to its discontinuation in four (19%). Arrhythmogenic effects were observed in 2 cases (9%). Propafenone is effective in greater than 50% of patients with paroxysmal atrial flutter or fibrillation, resistant to other antiarrhythmic agents. The incidence of side effects is high, but they are usually not severe and reversible.  相似文献   
103.
A commercial double-test tablet (Rosco PGUA/indole) for detection of beta-glucuronidase (beta-GUR) activity and indole production was evaluated on a collection of 393 isolates of Enterobacteria. Both beta-GUR and indole were positive on 96.6% of Escherichia coli strains. beta-GUR, only, was also detected in 25 Shigella spp., four Enterobacter cloacae, eight Citrobacter freundii, and five Salmonella enteritidis strains, none of which were indole producers. An additional 261 consecutive clinical isolates of oxidase-negative nonswarming Gram-negative bacilli were studied in a parallel comparative field trial against conventional identification methods. For 200 strains, the standard method and PGUA/indole test were performed from the primary culture plate. The remaining 61 (23.4%) required subculture before testing. Sensitivity, specificity, positive predictive value, and negative predictive value of PGUA/indole test in the screening for E. coli were, respectively, 94.1%, 100%, 100%, and 87.1%. In our experience, PGUA/indole test is a rapid, precise, simple-to-perform, and economical method for screening E. coli. However, the need for a large inoculum may limit its application on primary cultures.  相似文献   
104.
Clinical manifestations and surgical results are analyzed in a retrospective study of 16 patients with a Zenker's diverticulum. Pharyngoesophageal diverticulum are an uncommon anomaly, producing cervical dysphagia and recurrent airway infections. Treatment should be surgical, as earliest as possible. Morbidity is very low and mortality very rare.  相似文献   
105.
The authors describe the first three cases with a serologically confirmed hantaviral aetiology in the Czech Republic. It is the causal agent of haemorrhagic fever with renal syndrome, western type (strain CG 18-20, identical with the Puumala prototype). All patients come from a locality where since 1984 very actively a natural focus of hantaviral infection was investigated in small mammals, and where formerly groups of farmers were found with a high herd immunity with hantavirus. The disease was present in a mild to medium severe form with some sequelae. In the discussion the authors draw attention to the necessity of wider use of aetiological diagnosis in suspect diseases.  相似文献   
106.
107.
Alprazolam, a new benzodiazepine from triazolobenzodiazepine group, produced anxiolytic action in the conflict test with potency similar to that of diazepam. The myorelaxant activity of the drug was relatively weak. Unlike desipramine, alprazolam failed to reduce the immobility of rats in the forced swim test and was unable to prevent clonidine-induced hypothermia. Alprazolam, unlike desipramine, failed also to potentiate behavioral effect of noradrenaline injected into the hippocampus. Alprazolam after acute but not chronic administration antagonized the synchronizing effect of clonidine on EEG pattern. On the other hand, alprazolam similarly to tricyclic antidepressants, prevented the suppression of dominance behavior by clonidine in rats competing for food. The results indicate that alprazolam acts only weakly upon noradrenergic mechanisms related to depression and to antidepressant action of drugs.  相似文献   
108.
INTRODUCTION: Major or complicated pancreatic trauma in children is uncommon and management strategies remain controversial. The aim of this study was to evaluate our experience with both early and delayed surgery in these pediatric cases. METHODS: We carried out a retrospective analysis of data of pediatric patients with major or complicated pancreatic injury operated on between January 1994 and December 2005 in our pediatric trauma center. RESULTS: Thirteen children (9 boys and 4 girls) with a mean age of 8.5 years (range 3 - 16 years) were operated for major or complicated pancreatic injury. The extent of injury was: grade II (major contusion without duct injury or tissue loss) in 4 children; grade III (distal transection) in 5 children and grade IV injury (proximal transection) in four patients. Pseudocyst developed in 8 children: 4 with grade II injury, 2 with grade III injury and 2 with grade IV injury (one with abdominal pseudocyst and one with an abdominal and a mediastinal pseudocyst). Early diagnosis and operation was achieved in 5 cases, while delayed diagnosis and operation occurred in 8. Three children underwent cystogastrostomy; 6 had a spleen-sparing distal pancreatectomy and 4 had resection with Roux-en-Y jejunostomy drainage. Endoscopic retrograde cholangiopancreaticography (ERCP) was the most useful diagnostic tool in assessing ductal injury. There were no deaths or long-term morbidity in our group of patients. CONCLUSIONS: Our results support the view that early operation is important in ductal pancreatic injury. We recommend transferring children with a suspected ductal injury to a tertiary center with experience in both pediatric ERCP and pancreatic surgery.  相似文献   
109.
The present study describes, in animals, a novel approach to the in vivo, noninvasive determination of alcohol in the body. The concentration of ethanol in vapor above the lacrimal fluid in the eye was analyzed in situ by the use of a fast (1-min) gas sensor method developed previously for biological liquids. After an oral dose of 1 g/kg to 11 animals, eye vapor measurements and blood samples were obtained over 4 hr. The correlation of 61 blood ethanol concentrations obtained by the two methods yielded a correlation coefficient of 0.92 and a slope of 0.99. The metabolic rates of ethanol determined by gas chromatographic analysis of blood and by ethanol eye vapor analysis are virtually identical. The data suggest that ethanol eye vapor analysis may be an attractive, noninvasive method for the determination of ethanol in animals. The method is not subject to false high readings due to alcohol in the buccal cavity and thus might constitute an alternative to breath analysis in the human. In a separate series, ethanol was determined by head space gas chromatography in samples of blood and lacrimal fluid while the animals were under ketamine anesthesia. The correlation of ethanol concentrations in blood and lacrimal fluid (r = 0.99) shows that ethanol is distributed in lacrimal fluid which comprises part of total body water.  相似文献   
110.
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