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21.
Cefepime (BMY 28142) was compared with ceftazidime, cefotaxime, and moxalactam for efficacy in treating experimental meningitis in mice and neonatal rats. Mice were infected intracranially with Streptococcus pneumoniae, S. agalactiae, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa and treated intramuscularly. Five- to eight-day-old neonatal rats were injected intracisternally with Haemophilus influenzae, S. pneumoniae, and S. agalactiae and treated intraperitoneally. Cefepime was found to be the most active compound against induced meningitis in mice infected with S. agalactiae. Cefepime was as active as cefotaxime against Staphylococcus aureus meningitis, slightly more active than cefotaxime against S. pneumoniae and E. coli, and as active as ceftazidime against K. pneumoniae and P. aeruginosa meningitis. Cefepime was found to be the most active compound against S. pneumoniae and S. agalactiae meningitis in neonatal rats. Against H. influenzae, cefepime was as active as moxalactam and cefotaxime. Ceftazidime was the least active compound. The pharmacokinetics of cefepime in neonatal rats were similar to those of ceftazidime. Both compounds penetrated well into cerebrospinal fluid and brain tissues of uninfected neonatal rats. Relative concentrations were twice as high as those of cefotaxime and moxalactam.  相似文献   
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目的:研究证实,在众多生长因子中,肝细胞生长因子无论在体外还是体内都可以激活静止状态的肌卫星细胞,修复受损肌肉。采用脂多糖刺激体外培养的骨骼肌卫星细胞,观察肌卫星细胞产生肝细胞生长因子以及肌卫星细胞增殖分化的变化。方法:实验于2006-07/2007-05在华中科技大学同济医学院同济医院创伤外科实验室完成。①实验材料:健康SD成年雄性大鼠,体质量150~200g,由华中科技大学同济医学院实验动物中心提供。实验过程中对动物处置符合实验动物伦理学标准。②实验方法:分离SD大鼠后肢部分股四头肌肉进行骨骼肌卫星细胞的培养。取第2代细胞爬片,待细胞增殖到80%密度时,丙酮固定细胞,常规处理后进行α-sarcometricactin细胞免疫化学染色鉴定,以成纤维细胞作为阴性对照。取第3代骨骼肌卫星细胞,应用0,5,10,20mg/L脂多糖刺激体外培养的大鼠骨骼肌卫星细胞,采用ELISA方法测细胞培养液中的肝细胞生长因子的浓度。取第4代骨骼肌卫星细胞,用含体积分数为0.10胎牛血清的培养基配制成单个细胞悬液,调整浓度为5×107L-1,分成两组,一组加入10mg/L脂多糖,另一组不加任何干预。采用噻唑蓝(MTT)法测定卫星细胞的增殖率。结果:①以未经脂多糖处理的无血清培养基培养的肌肉卫星细胞培养液为对照,将对照组和5,10,20mg/L脂多糖处理组比较,各实验组肝细胞生长因子浓度明显高于对照组(P<0.05)。②5,10,20mg/L脂多糖刺激骨骼肌卫星细胞分泌的肝细胞生长因子水平差异无显著性。③肝细胞生长因子在脂多糖刺激后36h分泌浓度最高。④脂多糖刺激肌卫星细胞的增殖分化明显高于未经刺激的肌卫星细胞。结论:①脂多糖可诱导骨骼肌卫星细胞自分泌肝细胞生长因子。②不同质量浓度脂多糖培养基中肝细胞生长因子水平差异无统计学意义。③脂多糖具有促进骨骼肌卫星细胞增殖分化的效应。  相似文献   
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Background

Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil.

Methods

This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units.

Results

Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection.

Conclusions

Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters ≥ 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission.  相似文献   
27.
Lectin-mediated drug targeting: history and applications   总被引:8,自引:0,他引:8  
  相似文献   
28.
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts  相似文献   
29.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
30.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
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