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11.
Plasmids in group JK coryneform bacteria isolated in a single hospital   总被引:4,自引:0,他引:4  
Investigation of 39 JK-type coryneform isolates from patients at a single hospital revealed that 23 possessed plasmids, which formed six groups on restriction endonuclease analysis. Four of the groups were associated with production of similar bacteriocin-like substances, and shared a minimum of 6.4 kilobase pairs of DNA. These plasmids, found in isolates from different patients, provide strong direct evidence that person-to-person transmission of JK bacteria had occurred within the hospital.  相似文献   
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Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.  相似文献   
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This article examines recent developments in the role of general hospitals in providing treatment for alcoholism. It employs data on 5,000 U.S. short-term general hospitals and on all patients discharged from a subsample of 400 of these hospitals in the years 1980 through 1985. The article describes the growth in alcoholism treatment resources in short-term hospitals (1980-85) and examines linked hospital and patient data for the 400 hospitals in the subsample to describe patient diagnoses and resource use (1980 and 1985). Patients are classified by the stage of their alcohol problem, and hospital use is examined for patients in different stages.  相似文献   
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Heavy-resistance exercise utilizing very short rest periods is commonly used by body builders to prepare for competition. The purpose of this study was to compare the acute responses of this type of heavy-resistance exercise protocol in competitive body builders (BB) and power lifters (PL). Nine male BB and eight PL were matched for age, size and experience. A ten-station heavy-resistance exercise protocol was used. Each subject performed three sets of 10 repetition maximum (RM) with 10-s rest between sets and alternated 30-s and 60-s rest periods between exercises. No differences were observed in total work between the groups, but BB used a significantly (P less than 0.05) higher percentage of their 1 RM in the bench press and leg press exercises. Heart rate, ratings of perceived exertion (RPE), and lactate levels were obtained during the exercise protocol; significant (P less than 0.05) increases were observed above rest for these variables. RPE was significantly correlated with lactate levels (r = 0.84). Plasma epinephrine, norepinephrine, dopamine, cortisol, and lactate levels significantly increased from pre- to 5 min post-exercise. Mean plasma volumes were reduced -16.6 (+/- 3.64)% and -20.6 (+/- 8.32)% following the exercise protocol for BB and PL, respectively. Significant (P less than 0.05) decreases in eosinophil counts were observed following exercise. No significant differences were observed between BB and PL for any of the physiologic responses measured. PL exhibited a higher incidence (100%) of clinical symptoms of dizziness and nausea compared to BB (11.1%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
15.
Plasmid profiles have been established for 68 isolates of Staphylococcus aureus from 13 episodes of epidemic spread in hospital wards between 1958 and 1962. Despite the original lack of care in preservation of strains the profiles give, in general, the same epidemiological patterns as were established originally on the basis of phage type, antibiotic sensitivity, ward and date of isolation.  相似文献   
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
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Eight patients with malignant gliomas were monitored with clinical examinations to study the effects of the combination of intravenous administration of carmustine and infraophthalmic intra-arterial administration of cisplatin on retinal and optic nerve function. Three patients developed a severe macular retinal pigment abnormality in the eye ipsilateral to the intra-arterial infusion. Electrophysiologic studies disclosed no evidence of a generalized disturbance in the photoreceptors, middle retinal layers, or retinal pigment epithelium. In contrast to previous studies involving patients whose visual loss was caused by vaso-occlusive lesions in the retina and optic nerve, our study involved patients with clinically significant maculopathy, that was not vascular in origin and that developed after treatment with carmustine and cisplatin. We suggest that the deficit may result from a localized retinal pigment disturbance in the macula.  相似文献   
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