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1.
A. Hedberg H-G. Hårdemark B. Olsson-Liljequist J. Sjölin 《Clinical microbiology and infection》2004,10(8):765-768
Cerebrospinal fluid (CSF) concentration-time curves of rifampicin and fusidic acid were studied in a patient with post-operative meningitis caused by Staphylococcus epidermidis. The patient was treated with this combination of antimicrobial agents because of a severe hypersensitivity reaction to vancomycin. Peak CSF concentrations of rifampicin exceeded the MIC by > 60-fold, while those of fusidic acid just reached the MIC. CSF concentrations of fusidic acid were relatively stable within the range reported for patients with uninflamed meninges, but serum levels were surprisingly low. An increase in the metabolism of fusidic acid induced by rifampicin cannot be excluded. 相似文献
2.
The effect of three beta-lactamase inhibitors, clavulanic acid, sulbactam and tazobactam used in clinical practice were compared for their activity against purified beta-lactamases from Bacteroides uniformis, Clostridium butyricum and Fusobacterium nucleatum. The enzymes from B. uniformis and C. butyricum were produced in fermenters under controlled growth conditions and the enzyme from F. nucleatum was produced in batch cultures. Purification of the beta-lactamases was achieved by anion-exchange chromatography, gel filtration and FPLC-technique. The degree of inactivation of beta-lactamase activity was determined spectrophotometrically with nitrocefin as the substrate. The inhibitors in various concentrations were preincubated at 30 degrees C together with the enzyme for different time periods (0.5-120 min) before determination of the remaining beta-lactamase activity. The inhibitors all decreased the activity of the beta-lactamases investigated. Clavulanic acid and sulbactam were capable of reducing the enzyme activity of the B. uniformis beta-lactamase more effectively than the C. butyricum and F. nucleatum beta-lactamases. All beta-lactamases tested were more susceptible to tazobactam than to clavulanic acid and sulbactam. 相似文献
3.
In the present study, we have followed a national cohort of dentists, academics, i.e. people with three or more years of post-high school education, and the general population for a period of ten years, and identified all cases of recognized suicide during the period 1961 to 1970. The aim of the study was to assess whether suicide rates are higher among dentists even after adjustment for socioeconomic factors. Results show an elevated standardized mortality ratio (SMR) for male dentists compared to other male academics. Female dentists did not exhibit any increased risk. It is suggested that enhanced interest should be given to the possible etiologic role of not only psychosocial factors but also to psychoorganic consequences of mercury exposure among dentists. 相似文献
4.
G Samuelsson M H Farah P Claeson M Hagos M Thulin O Hedberg A M Warfa A O Hassan A H Elmi A D Abdurahman 《Journal of ethnopharmacology》1992,37(2):93-112
Thirty-five plants are listed, which are used by traditional healers in the central and southern parts of Somalia. For each species are listed: the botanical name with synonyms, collection number, vernacular name, medicinal use, preparation of remedy and dosage. Results of a literature survey are also reported including medicinal use, substances isolated and pharmacological effects. 相似文献
5.
The influence of serotonin on intravascular volume in the total capacitance circulation has not previously been examined. Thus, blood was drained from the venae cavae to an extracorporeal reservoir and returned to the right atrium at a constant rate so that total intravascular volume changes could be recorded as the inverse of changes in reservoir volume in 31 anaesthetized dogs. Serotonin (588 +/- 47 micrograms) in the left atrium was associated with an initial decrease in intravascular volume of 39 +/- 12 ml (P less than 0.01) followed by an increase of 129 +/- 31 ml (P less than 0.01) above control at 20 min. Mean arterial pressure increased from a control of 74 +/- 4 mmHg to 99 +/- 7 mmHg (P less than 0.01) initially and then decreased to 64 +/- 5 mmHg (P less than 0.05) at 20 min. Following ganglionic blockade with mecamylamine, serotonin caused only a decrease in intravascular volume, which was 73 +/- 12 ml (P less than 0.01) at 20 min. 5-HT2 and alpha-adrenergic blockade with ketanserin did not attenuate the early decrease in intravascular volume. 5-Carboxamidotryptamine (82 +/- 39 micrograms), a 5-HT1 agonist, was associated with only an increase in intravascular volume, which was 82 +/- 13 ml (P less than 0.01) at 20 min and which was abolished after ganglionic blockade. Thus, serotonin causes a biphasic change in total intravascular volume. The initial decrease in intravascular volume is not mediated by a reflex or by 5-HT1, 5-HT2, or alpha-adrenergic receptor stimulation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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8.
The purpose of the study was to investigate to what extent the physical activity pattern in adulthood can be predicted by physical characteristics, performance and activity in adolescence. A group of 62 men and 43 women completed a questionnaire concerning physical activity during their leisure time at the ages of 16 and 27 years. An activity index produced from the questionnaire. At the age of 16 years, the subjects were also tested for strength (strength test battery) and running performance (9-min run). Maximal oxygen uptake (
) was estimated from a submaximal test and a muscle biopsy specimen was taken and analysed for fibre types (percentages of types I, IIA, 1113). The proportion of subjects engaged in some kind of physical activity during their leisure time was approximately 70% among the women and 80% among the men at both ages. The time spent on physical activity (minutes per week) decreased with age for the men but not for the women. The women devoted less time. to physical activity than the men both at age 16 and 27 years. The attitude to endurance activities had changed to a more positive attitude among the women and to a less positive attitude among the men at age 27 years. The aerobic potential (
and percentage of type I fibre), running performance, strength performance, physical activity and marks in physical education at age 16 years explained 82% of the physical activity level in adulthood for the women and 47% for the men. The aerobic potential at age 16 years alone explained 31% of the adult physical activity level in the women and 24% in the men. Strength performance, physical activity and marks in physical education at age 16 years further increased the predictive value for the physical activity level in adulthood for the women but not for the men. It is suggested that the major portion of the variation in physical activity level in adult women, but not in the adult men, could be predicted from physical characteristics, physical performance, and the activity level in adolescence. 相似文献
9.
The expression of hypoxia-inducible factor 1alpha is a favorable independent prognostic factor in renal cell carcinoma. 总被引:4,自引:0,他引:4
Anders Lidgren Ylva Hedberg Kjell Grankvist Torgny Rasmuson Janos Vasko B?rje Ljungberg 《Clinical cancer research》2005,11(3):1129-1135
PURPOSE: Renal cell carcinoma (RCC) is the most common malignancy of the kidney composed of specific tumor types. The sporadic conventional RCCs are, in contrast to the other RCC types, characterized by a high rate of von Hippel-Lindau (VHL) mutations and hypermethylation. The majority of these tumors lack functional VHL protein (pVHL) that leads to increased hypoxia-inducible factor 1alpha (HIF-1alpha) expression. The pVHL is the physiologic regulator of the activity of HIF-1alpha by targeting it to the proteasome for degradation under normoxia. Both pVHL and HIF-1alpha target other genes that are important for cancer survival and proliferation. Expression of HIF-1alpha has been linked to poor prognosis in different malignancies, although few studies have been done on the relation between HIF-1alpha and clinical variables in RCC. EXPERIMENTAL DESIGN: HIF-1alpha protein expression was analyzed in tumor tissue from 92 patients with RCC. HIF-1alpha was quantified by Western blot relative to a positive control. RESULTS: The HIF-1alpha protein was expressed as two bands which strongly correlated (r = 0.906, P < 0.001); therefore, they were added and the sum evaluated against clinicopathologic variables. There was no association between HIF-1alpha and gender, stage, grade, tumor size, or vein invasion. Conventional RCCs had significantly higher HIF-1alpha expression compared with papillary and chromophobe RCCs and kidney cortex. In conventional RCC, HIF-1alpha was an independent prognostic factor. CONCLUSION: HIF-1alpha levels varied significantly between the different RCC types. In conventional RCC, HIF-1alpha was an independent prognostic factor. These data indicate that HIF-1alpha is involved in tumorogenesis and progression of RCC. Evaluation of other HIF target gene products and correlation to angiogenesis seems warranted. 相似文献