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Thirty-eight nontoxigenic strains ofCorynebacterium diphtheriae isolated between 1987 and 1992 from clinical specimens of French patients were typed by biotyping, antibiograms, bacteriophage typing, ribotyping, and restriction analysis by pulsed-field gel electrophoresis (PFGE). Excellent correlation occurred between the genotypes defined by PFGESfil profiles or by ribotypeBstEll profiles. Genotyping revealed seven genotype patterns among the 26 biotype mitis isolates, five among the nine biotype gravis isolates, and three among the three biotype belfanti isolates. Phage typing was nonreactive for nine of the 38 isolates. A combination of all the typing methods led to the identification of 19 different types ofCorynebacterium diphtheriae.  相似文献   
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The essential amino acid, tryptophan, has been shown to lower blood pressure in rats when administered orally or intravenously. In order to potentially enhance this action, a brain-targeting chemical delivery system (CDS) approach was applied to this compound. The CDS is based on a dihydropyridine----pyridinium ion redox system, chemically analogous to the naturally occurring NADH----NAD+ system. The dihydropyridine moiety containing carrier is chemically attached to the amino group by an amide-type bonding while the carboxylic acid functionality is esterified to various alcohols. Physicochemical studies of the new derivatives were performed. The determined chromatographic Rm values indicate an increased lipophilicity for the CDSs compared to the parent compound. Oxidation stability studies performed on selected compounds using a ferricyanide-mediated method showed that the CDSs are oxidized to the respective quaternary salt forms. Activity studies performed in deoxycorticosterone acetate induced hypertensive rats, demonstrated that the delivery system for tryptophan reduced blood pressure more efficiently for a longer time than did the parent compound.  相似文献   
15.
The promoting effect of cyclic monoterpenes, 1% limonene (CAS 5989-27-5) and 1% cineole (CAS 470-82-6), on percutaneous absorption of nonsteroidal anti-inflammatory drugs was investigated in the rats. Compared with 1% laurocapram, drug absorption from the gel ointments was significantly more enhanced by addition of 1% limonene, while without any enhancer only ibuprofen penetrated across the skin in the limited amount. When using formulation with propylene glycol or 50% propylene glycolethanol solution, instead of carboxyvinyl polymer gel, percutaneous absorption significantly decreased and neither limonene nor cineole or laurocapram were capale to promote percutaneous absorption of flufenamic acid to sufficient serum level. Cineole and limonene were also evaluated in permeation experiments in vitro. Enhancement ability of limonene in the gel oinment was approximately 5 times higher comparing with enhancement ratio of cineole, while in 100% propylene glycol enhancement ability of both cyclic monoterpenes was equal. Good correlation was observed between in vivo and in vitro experiments. Evaluation of solubility proved that in the gel ointment simulated as water-ethanol solution were relatively best condition for percutaneous absorption of flufenamic acid when comparing with propylene glycol or 50% propylene glycol-ethanol solution.  相似文献   
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We report the first case of a human immunodeficiency virus (HIV)-related primary hepatic leiomyoma in an adult patient. The diagnosis was made at autopsy and confirmed by immunohistochemistry. Epstein Barr virus (EBV) was identified in tumour cells by in situ hybridization. Review of the literature revealed 13 cases of visceral myogenic tumours occuring in acquired immunodeficiency syndrome children, and only 2 cases in adults. One was a spinal epidural leiomyoma, the other multiple smooth muscle tumours of the colon and adrenal gland. This is the first report of EBV in smooth muscle neoplastic cells in an HIV-infected adult patient.  相似文献   
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This paper explores the connection between alcohol-related mortality, drinking behavior, and macroeconomic conditions in Finland using both aggregate and microlevel data from recent decades. The aggregate data reveal that an improvement in economic conditions produces a decrease in alcohol-related mortality. Microlevel data show that alcohol consumption increases during economic expansion while the probability of being a drinker remains unchanged. This demonstrates that alcohol-related mortality and self-reported alcohol consumption may be delinked in the short-run business cycle context. One explanation for this paradox is that most harmful forms of drinking are not captured in survey-based data used to study the effect of macroeconomic conditions on alcohol consumption. Our evidence does not overwhelmingly support the conclusions reported for the United States that temporary economic downturns are good for health.  相似文献   
18.
Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal cancer response to preoperative radiotherapy (RT). Methods and material Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I), or to short RT and 4–5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37°C, and the BrdUrdLI was calculated as a percentage of BrdUrd-labeled cells. Results Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios were calculated separately for fast (BrdUrd LI > 8.5%) and slowly (BrdUrd LI ≤ 8.5%) proliferating tumors and correlated with overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation was observed only in slowly proliferating tumors. Conclusions Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI was correlated to inhibition of proliferation in responsive tumors. The paper was presented at ECCO 13, October 30 to November 03, 2005 in Paris, France  相似文献   
19.
Staphylococcal necrotizing pneumonia producing the Panton Valentine leukotoxin (PVL) has been described for many years. The french reference center for staphylococcal toxaemia defined it with precision in 1999. A 10-year-old child, died in 36 hours from respiratory distress and shock. Staphylococcal pneumonia was suspected then confirmed: S. Aureus producing PVL was isolated in lung, blood and articulations.  相似文献   
20.
Fifty-four patients with complicated UTI were administered ciprofloxacin in doses of 500 mg (30 subjects) and 250 mg (24 subjects) at 12-hour intervals. While a positive effect was noted in 96–100% upon termination of therapy, the effect was still present 3 weeks later in 90% of the high-dose, but only in 71% of the low-dose group. In 23 patients with uncomplicated UTI, a positive effect of the three-day therapy with 100 mg of ciprofloxacin at 12-hour intervals was observed in 91% of subjects. Intolerance to the agent was found in one case only. Development of resistance to ciprofloxacin was not observed.  相似文献   
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