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81.
OBJECTIVES: To assess the clinical outcome and risk of failure after oral vs. intravenous treatment in otitis media caused by penicillin-resistant pneumococci. To determine the possible correlations between pneumococcal minimal inhibitory concentration (MIC) to penicillin and clinical outcome. DESIGN: Retrospective study of 156 cases collected between 1993 and 1995. Mean follow-up: 5 months. Setting. Two tertiary academic medical centers in Paris, France. PATIENTS AND METHODS: Pneumococcus was isolated from 191 of 570 ear samples obtained from children with otitis media and shown to be penicillin-resistant in 156. Medical history, antibiotic therapy during the previous 3 months and day-care center attendance were reviewed. For the current episode microbiologic characteristics of the isolated strains, type of treatment, therapy efficacy and clinical outcome were analyzed. Patients were predominantly young (76.3% were <1 year old) and bacteriologic samples were taken mainly because of previous treatment failure. RESULTS: Among 156 children with pneumococcal penicillin-resistant otitis media, 72.2% attended day-care centers, 71.8% had been previously treated with aminopenicillin and 52.5% with cephalosporins. Failure of previous empirical oral therapy was noted in 84% (one-third of these had been receiving amoxicillin-clavulanate). Patients treated intravenously had had a more protracted otitis but no greater number of previous episodes of acute otitis media than those receiving oral therapy. Acute mastoiditis occurred in 4 infants resulting in mastoidectomy. Oral treatment (mainly with high dose amoxicillin,120 to 150 mg/kg/day) and intravenous therapy (cephalosporin or glycopeptide) had been used in 59 and 41%, respectively. Mean duration of therapy was 10.7 days. Three failures (1.9%) and 10 recurrences (6.4%, average 28 days) occurred. No statistical difference was found between intravenous and oral therapy with respect to risk of recurrence. A high penicillin MIC value was correlated with previous antibiotic treatment but not with clinical outcome. CONCLUSIONS: Oral therapy appears to be as effective as intravenous therapy for the treatment of penicillin-resistant pneumococcal otitis media. Intravenous treatment should not necessarily be dictated by the penicillin susceptibility value but should be considered in cases of failure to thrive, persistent otitis or other complications.  相似文献   
82.
介绍了圆片级可靠性技术产生的背景,对其特点和作用作了详细的论述。测试内容上着重介绍了金属化完整性测试、氧化层完整性测试、连接完整性测试和热载流子注入测试,根据测试数据,对1.0μm工艺线单一失效机理的可靠性进行了评价,对不同测试结构的作用进行了说明。  相似文献   
83.
More than 35% of atria in Hong Kong can be classified as linear with large transverse dimensions. The smoke filling process due to fires in these atria was studied. Both the zone model and the computational fluid dynamics (CFD) field model were used. A linear atrium of volume 7,500 m3 was taken as an example. The multicell concept was used while simulating the smoke filling process with the zone model. Results were also justified by studying the smoke filling patterns in a scale model. The effects of the space volume on the smoke filling process was studied in three larger atria with volumes of 15,000, 22,500, and 30,000 m3. Finally, natural smoke-control systems, using horizontal ceiling vents in the first atrium, were studied.  相似文献   
84.
Non-infectious virus-like particles of SIVsmB7 that expresses env and gag gene products but are defective in pol and vpx/vpr were assessed for their ability to induce protective immunity against infection with pathogenic SIVsmE660 in rhesus macaques. Animals were immunized in three groups: group A was primed with cell-associated SIVsmB7 and boosted with cell-free SIVsmB7; group B was primed with cell-free SIVsmB7 and boosted with cell-free SIVsmB7 conjugated to iron oxide microbeads; group C was primed with cell-free SIVsmB7 mixed with Titer Max adjuvant and boosted with cell-free SIVsmB7 mixed with SAF-M adjuvant followed by secondary boosting with cell-free SIVsmB7 conjugated to microbeads. Animals were challenged intravenously with 20 animal infectious doses of SIVsmE660 grown in rhesus peripheral blood mononuclear cells 3 weeks after final boosting. All animals became infected as evidenced by quantitative virus cultivation. Sera from immunized animals contained low-titer antibodies by ELISA and low or undetectable neutralizing antibodies on the day of challenge but strong anamnestic antibody responses were observed following challenge. Interestingly, 2 of 3 animals in group A showed evidence of transient viremia and more stable CD4 counts following challenge as compared to the other immunized animals and to non-immunized controls. Thus, immunization with cell-associated SIVsmB7 did not provide sterilizing immunity against challenge with a highly pathogenic SIV strain but might have caused virus clearance later in infection.  相似文献   
85.
OBJECTIVE: To determine the changes in cardiovascular risk factors and psychological and physical symptoms that occur during the perimenopause. DESIGN: Cohort study of 541 healthy middle-aged premenopausal women followed up through the menopause. SETTING: General community. PARTICIPANTS: After a baseline evaluation taken at study entry, 152 women ceased menstruating for 3 months (not due to surgery) and were not using hormone replacement therapy, and were reevaluated in a similar protocol (perimenopausal examination); 105 of the 152 were evaluated a third time when they had ceased menstruating for 12 months and were not using hormone replacement therapy (postmenopausal examination). One hundred nine premenopausal women who were repeatedly tested constituted a comparison group. MAIN OUTCOME MEASURES: Levels of lipids and lipoproteins, triglycerides, fasting glucose and insulin, blood pressure, weight, height, and standardized measures of psychological symptoms. RESULTS: Women who became perimenopausal showed increased levels of cardiovascular risk factors, which were similar in magnitude to those experienced by the comparison group of premenopausal women. Perimenopausal women reported a greater number of symptoms, especially hot flashes, cold sweats, joint pain, aches in the skull and/or neck, and being forgetful; reports of hot flashes at the perimenopausal examination were associated with low concentrations of serum estrogens. Menopausal status was not associated with depressive symptoms. Perimenopausal women who became postmenopausal showed a decline in the level of high-density lipoprotein-2-cholesterol (means, 0.53 to 0.43 mmol/L [20.6 to 16.7 mg/dL]) and a gradual increase in the level of low-density lipoprotein cholesterol (means, 3.14 to 3.33 mmol/L [121.3 to 128.8 mg/dL]), whereas symptom reporting declined. CONCLUSIONS: During mid-life, women experience adverse changes in cardiovascular risk factors and a temporary increase in total number of reported symptoms, with no change in depression. Preventive efforts to reduce the menopause-induced increase in cardiovascular risk factors should begin early in the menopausal transition.  相似文献   
86.
The dynamics of the transition of Y.pseudotuberculosis to the latent (noncultivable) state in sterile soil extraction and in soil extraction, containing Scenedesmus algae or their exometabolites, was evaluated by the bacteriological method and with the use of polymerase chain reaction. The formation of Y.pseudotuberculosis latent forms achieved its highest rate under the action of algal exometabolites (on day 11), while in the presence of algal cells such formation was delayed to 3-5 months. The partial reversion of Y.pseudotuberculosis nonculativable forms to vegetative, bacteriologically detectable forms occurred under the action of fetal serum, as well as live or killed infusoria. Transmission electron microscopy demonstrated that noncultivable Y.pseudotuberculosis had a round form, diminished cell size, denser cytoplasm and enlarged cytoplasmic space. The reversible transition of bacteria to the latent state is regarded as their adaptation to unfavorable factors during their existence in soils and water reservoirs.  相似文献   
87.
The purpose of this study was to estimate the risk of suicide for patients with Parkinson's disease (PD) in Denmark compared with that in the background population. The study involved 458 patients with a PD diagnosis, 226 men and 232 women. The follow-up period to either death or end of follow-up on December 31, 1990 was 0 to 17 years, mean 5.7 years. Deaths in the follow-up period amounted to 254, 135 men and 119 women. Two women committed suicide. The number of expected suicides was 1.06 for men and 0.55 for women, a total of 1.62. Neither for men nor for women was the difference between expected and observed suicides statistically significant.  相似文献   
88.
Fibroblast Growth Factors 3 (FGF-3) and 4 (FGF-4) were compared for the effects they each exert on EF43 mouse cells. This non-transformed mammary cell line appears to be myoepithelial mainly because it expresses alpha-smooth muscle actin. The EF43 cells were infected with similar vectors that carry either the short fgf-3 sequence (the product of which goes into the secretory pathway), fgf-4 or the selection gene only as control. In syngeneic animals, EF43.fgf-3 cells were tumorigenic only when orthotopically implanted whereas EF43.fgf-4 cells invariably gave rise to aggressive tumors. However, both tumor types were metastatic as evidenced by the blue micrometastases observed when the implanted cells expressed lacZ. In vitro, the FGF-3 producing cells were strongly invasive in matrigel coated chambers whereas the EF43.fgf-4 cells only were invasive in type I-collagen gels. Interestingly, FGF-3 production greatly stimulated the synthesis of pro-MMP-9 (Matrix Metalloprotease-9) and, to a lesser extent, that of pro-MMP-2. FGF-3 also up-regulated the production of plasminogen activators. In contrast, FGF-4 had no effect on these secretions and the medium conditioned by the EF43.fgf-4 cells displayed the largest plasminogen activator-inhibitor activity. These results show that FGF-3 and FGF-4 have distinct mechanisms of action on myoepithelial cells.  相似文献   
89.
The hemagglutinating virus of Japan (HVJ)-liposome method involves the entrapment of DNA and nuclear protein within liposomes and the use of HVJ to enhance liposome fusion with cell membranes. This method has been used successfully for in vivo gene transfer to various types of tissue. In this study, we investigated whether this method transfers genes effectively to normal and malignantly transformed keratinocytes in vivo. We applied HVJ-liposome complex (HLC) containing the beta-galactosidase gene to the tape-stripped skin of hairless rats and detected the enzyme activity in the keratinocytes of the treated skin. Comparison of this method with the naked DNA injection method, which was shown recently to be useful for in vivo gene transfer to keratinocytes, demonstrated that the transfer efficiency of the latter was about 5 times higher than that of the former. We assessed the efficacy of the HVJ-liposome method for gene transfer to transformed keratinocytes by examining the effect of HLC containing the herpes simplex virus thymidine kinase gene on the growth of mouse squamous cell carcinomas. Local injection of HLC into the tumors followed by administration of ganciclovir to mice resulted in tumor growth inhibition. These results indicate that the HVJ-liposome method is suitable for in vivo gene transfer to keratinocytes; also that this method may prove a good tool for basic research into keratinocyte biology and future keratinocyte gene therapy.  相似文献   
90.
The conversion of proparathyroid hormone to parathyroid hormone (PTH) was studied in vitro employing pancreatic trypsin as a prototype converting enzyme. Digestion of intact radiolabeled bovine prohormone with trypsin (0.1%) (w/w) resulted in release of a peptide comigrating with intact hormone marker in systems resolving both on the basis of charge (urea polyacrylamide gels, pH 4.4) and size (sodium dodecyl sulfate-urea polyacrylamide gels, pH 7.2). Tryptic digestions of a synthetic analogue of bovine prohormone, ProPTH-(-6 + 34), consisting of the prohormone hexapeptide covalently bonded to the NIH2 terminus of the active fragment of the hormone, released in high yield the hexapeptide and the intact active hormone fragment before any other smaller fragments. Analyses of digestions were by: (i) thin-layer chromatography and amino acid analysis of digestion products; (ii) comparison of the biological activity of the prophormone substrate and the products of digestion; and (iii) peptide end-group analysis by the Edman method during progressive tryptic hydrolysis over 22 h. The latter experiments demonstrated cleavage of more than 75% of the hexapeptide-hormone peptide bond before cleavage of other trypsin-sensitive sites within the molecule. It is concluded that the specificity of cleavage at the hexapeptide-hormone bond in the process of intracellular hydrolysis of proparathyroid hormone resides primarily in the sequence and/or conformation of the precursor molecule; inasmuch as conversion of prohormone to hormone can be efficiently accomplished by pancreatic trypsin in vitro, there is, therefore, no need to postulate the existence of an intracellular converting enzyme within the parathyroid cell that possesses unique hydrolytic specificity.  相似文献   
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