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Human pharmacokinetics and distribution in various tissues of ceftriaxone   总被引:3,自引:0,他引:3  
Multiple-dose pharmacokinetics of ceftriaxone were investigated in 7 patients with bronchopneumonia using an intramuscular regimen of 1 g given every 24 h for 7 days. Serum, sputum, and urine samples were collected serially following the first dose (day 1) and last dose (day 7). Mean peak serum concentrations of ceftriaxone occurred at 2 h on both days and were 67.8 and 75.1 micrograms/ml, respectively, on day 1 and day 7. Ceftriaxone had a half-life of 6.9 h on day 1 and 7.4 h on day 7. The half-life of ceftriaxone in sputum was 5.9 and 6.6 h, respectively, on days 1 and 7. Approximately 50% of the dose of ceftriaxone was recovered in the urine within 24 h on day 1, 60% on day 7. Tissue distribution of ceftriaxone was determined in 103 patients following intramuscular administration of a single 1-gram dose at different times up to 24 h prior to surgery. High concentrations of ceftriaxone were found in lung, tonsil, middle ear mucosa, and nasal mucosa, and therapeutic levels of ceftriaxone persisted for 24 h after administration.  相似文献   
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A patient without evident immune deficiency who received a transfusion of blood from a second-degree family member developed fatal transfusion- associated graft-versus-host disease (TA-GVHD). The donor was homozygous for an HLA haplotype for which the recipient was heterozygous (one-way HLA match). All 39 reported cases of TA-GVHD in immunocompetent patients were reviewed to ascertain the predisposing factors and to define the indications for irradiating blood for this population. HLA typing was described in 15 cases; in 13, including seven related and six unrelated donors, a one-way HLA match was present. Thirty-one (79%) of the 39 cases were reported from Japan (and 196 other cases are cited in the Japanese literature), but a one-way HLA match among unrelated donors at HLA-A, -B, -DR loci is only approximately two to four times more likely in Japanese persons than in whites. Fresh blood (< 96 hours old) was used in 29 (94%) of the 31 cases reported from Japan and in 33 (87%) of 38 cases overall (in one case, the age of the blood used was not reported). Thus, factors that appear to predispose to TA-GVHD in immunocompetent patients are a one- way HLA match, fresh blood, and, possibly, Japanese ancestry. Irradiating cellular blood components from all blood relatives of transfusion recipients will not completely eliminate the risk of TA- GVHD.  相似文献   
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Aim:   Coronary artery calcification (CAC) has been associated with higher mortality in chronic renal disease. The purpose of this study was to assess coronary artery calcium score (CaCs) in haemodialysis patients and to correlate calcium scores with clinical parameters and mortality.
Methods:   A cross-sectional study was conducted in 59 haemodialysis patients. CaCs was assessed by multidetector-row computed tomography and stratified as: CaCs of less than 10 Agatston units (U), no calcification; CaCs of 10–400 U, mild-to-moderate; and CaCs of more than 400 U, severe calcification. The effects of age, haemodialysis duration and biochemical and inflammatory markers on CaCs logarithm were evaluated by multiple linear regression analysis. Cox regression analysis was used to measure the impact of CaCs of more than 400 on 2-year mortality.
Results:   Coronary calcifications were detected in 64.5% of patients, and the median of CaCs was 31.7 U (0–589.7) with a range of 0–5790.0 U. Twenty-one (35.5%) patients had mild-to-moderate and 17 (29%) severe CaCs. Patients with severe CaCs were older and showed a higher prevalence of ischaemic heart disease and a higher body mass index ( P  = 0.04). A trend towards higher C-reactive protein levels was found in patients with severe CaCs. Advanced age was the only variable that influenced CaCs logarithm independently. The effect of severe CaCs on 2-year mortality did not persist after adjustment for other covariates.
Conclusion:   Coronary calcification was highly prevalent in these uraemic patients on chronic haemodialysis. A correlation was evidenced between CaCs and advanced age, but severity of the CAC score did not have an impact on 2-year mortality of this cohort.  相似文献   
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Atresia of the submandibular ducts (particularly the duct orifice) is a rare occurrence that is mainly observed in newborns or infants; moreover, its differential diagnosis with other anomalies of the oral floor is sometimes difficult. Given the lack of data concerning the differences between atresia of the orifice of Wharton's duct and other anomalies of the submandibular duct system, we describe here the findings of videosialoendoscopic assessment of the salivary duct system in an infant who underwent traditional surgery for bilateral atresia of the orifice of Wharton's duct. During sialoendoscopy, a trifurcation of the main duct, a normal variant of the more common bifurcation of the secondary branches of the salivary duct system, was observed bilaterally. No other ductal anomalies were encountered. Complete resolution of the symptoms and complete patency of both ducts at 19-month follow-up evaluation were observed. In conclusion, although spontaneous resolution of the disease during feeding is possible, minimal incision of the orifice of the imperforated submandibular duct together with diagnostic videosialoendoscopy of the main salivary duct system may be considered as part of the modern approach to salivary obstructive disorders in pediatric age as is currently the case for sialolithiasis and recurrent juvenile parotitis.  相似文献   
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Oral Diseases (2010) 16 , 160–166 Objective: The aim of this comparative study was to analyze cytopathologically and chemico‐physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. Materials and methods: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back‐scattered) scanning electron microscope (SEM) and X‐ray microanalysis to study piercing fragments. Results: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X‐ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. Conclusions: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted.  相似文献   
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