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91.
PURPOSE: To assess the in vitro susceptibility of the most common ocular bacterial isolates to several antibiotics and verify changing trends in the antibiotic susceptibility in a 15-year period. DESIGN: Experimental study. METHODS: All cultures positive for Staphylococcus aureus, coagulase-negative Staphylococcus (CNS), Streptococcus sp, and Pseudomonas sp in conjunctival (n = 4,585) and corneal (n = 3,779) samples from patients seen at the Federal University of S?o Paulo from 1985 to 2000 were evaluated. Cultures were performed in liquid and solid media, and susceptibility tests were done to amikacin, gentamicin, neomycin, tobramycin, ciprofloxacin, norfloxacin, ofloxacin, cephalothin, and chloramphenicol. RESULTS: Amikacin and neomycin showed an improvement of their sensitivity during the study period (88%-95% and 50%-85%, respectively) for corneal and conjunctival samples. Gentamicin and tobramycin revealed a decrease of sensitivity in time, from 95% to less than 80% in corneal and conjunctival samples. Ciprofloxacin, norfloxacin, and ofloxacin had good sensitivity to all evaluated bacteria, better in conjunctiva (95%) than in cornea (90%). Sensitivity of S. aureus to cephalothin decreased during the study but was still 98% for CNS. Chloramphenicol had good sensitivity to S. aureus (85% in corneal and 92%in conjunctival samples), CNS (87% and 88.5%), and Streptococcus sp (95% and 96%). CONCLUSIONS: Gentamicin, tobramycin, and cephalothin decreased their in vitro susceptibility to all tested pathogens. The fluoroquinolones remained a good choice in the treatment of ocular infections, with high suscep-tibility to all pathogens tested. Chloramphenicol also revealed an increase in its susceptibility to all bacteria evaluated.  相似文献   
92.
PURPOSE: To investigate the effect of orally administered trimethoprim-sulfamethoxazole (TMP-SMZ) on the prevalence, species distribution, and resistance of the conjunctival bacterial flora in adults with human immunodeficiency virus (HIV) infection. DESIGN: Cross-sectional study, with clinical and experimental laboratory investigation. METHODS: Samples from the inferior conjunctival fornix were collected and submitted for culture to evaluate aerobic flora. RESULTS: Sixty samples were collected. Negative cultures were found in 17 (56.7%) eyes of the TMP-SMZ group and in 10 (33%) of the control group (P = .036). All Staphylococcus species isolates in the TMP-SMZ group were resistant to the drug, whereas 50% of the control group presented this finding (P = .025). In the study group, all bacteria were resistant to TMP-SMZ, compared with only 47% of the microorganisms in the control group. CONCLUSION: Orally administered TMP-SMZ in patients with HIV infection seems to exert a selection pressure in the microorganisms present on the conjunctiva.  相似文献   
93.
BACKGROUND: Great public concern about health effects of dioxins emitted from municipal solid waste incinerators has increased in Japan. This paper investigates the association of adverse reproductive outcomes with maternal residential proximity to municipal solid waste incinerators. METHODS: The association of adverse reproductive outcomes with mothers living within 10 km from 63 municipal solid waste incinerators with high dioxin emission levels (above 80 ng international toxic equivalents TEQ/m3) in Japan was examined. The numbers of observed cases were compared with the expected numbers calculated from national rates adjusted regionally. Observed/expected ratios were tested for decline in risk or peak-decline in risk with distance up to 10 km. RESULTS: In the study area within 10 km from the 63 municipal solid waste incinerators in 1997-1998, 225,215 live births, 3,387 fetal deaths, and 835 infant deaths were confirmed. None of the reproductive outcomes studied here showed statistically significant excess within 2 km from the incinerators. However, a statistically significant peak-decline in risk with distance from the incinerators up to 10 km was found for infant deaths (p=0.023) and infant deaths with all congenital malformations combined (p=0.047), where a "peak" is detected around 1-2 km. CONCLUSION: Our study shows a peak-decline in risk with distance from the municipal solid waste incinerators for infant deaths and infant deaths with all congenital malformations combined. However, due to the lack of detailed exposure information to dioxins around the incinerators, the observed trend in risk should be interpreted cautiously and there is a need for further investigation to accumulate good evidence regarding the reproductive health effects of waste incinerator exposure.  相似文献   
94.
Adenovirus-mediated wild-type p53 gene transfer induces apoptosis in a variety of human cancer cells. Although clinical trials have demonstrated that a replication-deficient recombinant adenovirus expressing the wild-type p53 gene (Ad-p53) is effective in suppressing growth of non-small cell lung cancer (NSCLC), we often experienced late resistance to this treatment. To elucidate the mechanism of late resistance to Ad-p53 in human lung cancer cells, we generated 5 different resistant variants from p53-susceptible H1299 NSCLC cells by repeated infections with Ad-p53. We first examined the transduction efficiency of adenoviral vector by Ad-LacZ transduction followed by X-gal staining in parental and 5 resistant H1299 cell lines. Their sensitivity to viral infection decreased in correlation with the magnitude of resistance, and Ad-p53-mediated tumor suppression could be restored by dose escalation of Ad-p53 in the resistant variants. The expression of Coxsackie and adenovirus receptor (CAR) and alphaV integrins, which are cellular receptors for attachment and internalization of the virus, respectively, was next investigated in these cell lines. Flow cytometry revealed that alphaVbeta3 and alphaVbeta5 integrin expression was consistent, while p53-resistant cell lines showed that diminished CAR expression correlated with the magnitude of the resistance. Our results demonstrated that decreased CAR expression could be one of the mechanisms of late resistance to Ad-p53, which may have a significant impact on the outcome of adenovirus-based cancer gene therapy.  相似文献   
95.
OBJECTIVE: In 196 type 1 diabetic subjects and 195 nondiabetic subjects aged 30-55 years, we examined whether C-reactive protein (CRP) is elevated in diabetes and whether CRP is associated with coronary artery calcification (CAC). RESEARCH DESIGN AND METHODS: CRP was measured with a highly sensitive immunoassay. CAC was measured using electron beam computed tomography. RESULTS: CRP was elevated in diabetic women compared with nondiabetic women (median 1.62 vs. 0.85 mg/l, P < 0.001) independently of other factors, but was similar in diabetic and nondiabetic men (median 0.82 vs. 0.81 mg/l). Insulin dose per day was positively correlated with CRP in diabetic women (Spearman's rho = 0.36, P = 0.0003) but much less so in men (rho = 0.16, P = 0.09). Being in the top tertile for CRP was associated with CAC in diabetic and nondiabetic men even after adjustment for other risk factors (adjusted odds ratio [OR] = 4.6 and 4.3, respectively, P = 0.02 for both). In nondiabetic women, being in the top tertile for CRP was associated with CAC (OR 3.1, P = 0.04), but not independently of BMI (OR = 1 after adjustment). Among diabetic women the association was not significant even before adjustment for BMI (OR = 2.6, P = 0.07). CONCLUSIONS: Elevated CRP in diabetic women might reflect a particular sensitivity to insulin levels or might reflect insulin resistance. In general, CRP is an important marker of subclinical atherosclerosis, but the clinical significance of elevated CRP in diabetic women needs to be addressed in prospective studies, since CRP was not clearly associated with CAC in this group.  相似文献   
96.
Cardiopulmonary bypass technology transfer: musings of a cardiac surgeon   总被引:1,自引:0,他引:1  
The development of cardiopulmonary bypass (CPB) has been one of the greatest technical advancements in cardiovascular medicine. With heparin anticoagulation, this device can safely replace the circulatory and gas-exchanging functions of the heart and lung, facilitating complex cardiac operations. Limitations still exist however, related to blood reactions at the biomaterial surface, such as cell activation, inflammation and low-grade thrombosis. In this brief review, the thought processes which paralleled the development of CPB biocompatible surfaces such as heparin-coating, will be explored, as well as current theories on the suspected mechanisms by which heparin-coated surfaces act as an anti-inflammatory device during CPB. Results with new surfaces for CPB designed to capitalize on superior protein adsorption properties, such as surface modifying additive (SMA) and poly (2-methoxyethylacrylate) (PMEA), will also be described. Finally, the significance of biomaterial-independent blood activation will be discussed, emphasizing the current need to develop strategies utilizing optimal biomaterials, modified surgical technique and pharmacologic therapy to minimize the systemic complications of CPB.  相似文献   
97.
OBJECTIVE: We compared patient outcomes using two protocols: one routinely and the other selectively evaluating the calves completely during sonographic assessment of the lower extremities in patients with suspected deep venous thrombosis. SUBJECTS AND METHODS: In this randomized prospective study, patients were assigned to two groups. In one group, the deep calf veins were routinely evaluated in their entirety, and in the other group the calf was not evaluated unless the patient had symptoms or physical signs in the calf, in which case only the areas of symptoms or physical signs were evaluated. Patients were followed up for 3 months by medical record review, physician surveys, and telephone calls. An adverse outcome was a propagated deep venous thrombosis into the thigh or a pulmonary embolus. Examination times were recorded when possible. RESULTS: Of the 235 patients in the group in which the deep calf veins were routinely evaluated, we saw no adverse outcomes (0.0%; 97.5% one-sided confidence interval [CI], 0.6-1.6%). Of the 261 patients in the group in which the calf was only evaluated if there were signs or symptoms, we saw two adverse outcomes (0.8%; 95% CI, 0.1-2.7%). CONCLUSION: We found no significant difference in adverse outcomes in patients undergoing a protocol in which the deep calf veins were routinely evaluated or a protocol in which the calf was evaluated only if physical signs or symptoms were present.  相似文献   
98.
OBJECTIVES: The physical and mental condition of elderly people changes every day and we hypothesized that this influences food intake and swallowing functions. The present study was undertaken to clarify relationships between daily living conditions and swallowing function. METHODS: The subjects were users (105 males and 219 females) of 6 day-service centers. We performed a survey of IADL (Instrumental Activities of Daily Living), mobility, eating and swallowing behavior, and general health. In addition, we used RSST (Repetitive Saliva Swallowing Test) as a screen for functional dysphasia. RESULTS: Women who had normal food ingestion and swallowing functions were capable of doing shopping, housework and taking care of money independently. Males and females who were capable of moving around from place to place had normal food ingestion and swallowing functions. With regard to daily eating habits and health condition, males and females who had normal food ingestion and swallowing functions were able to consume ordinary food, able to eat without any help, and often laugh. CONCLUSION: It was concluded that a normal swallowing condition in the elderly is related to laughing often, being independent in daily life, moving around and eating ordinary meals without any help.  相似文献   
99.
This study aimed to identify changes in knowledge and practices learned to prevent dengue fever in two areas of Catanduva, S?o Paulo State, from 1999 to 2001: a study area and a control area. The study included an initial quantitative survey, qualitative research, a preliminary diagnosis presented to the community to launch a discussion aimed at defining future actions, implementation of the actions in the study area with community participation (but without changes in the control area), and a final comparison of the two areas. Changes in the study area included: vector control workers began demonstrating preventive measures without removing potential breeding places or using larvicide; use of educational aids specific to the local reality; activities related to the residents priorities; and activities such as music, theater skits, scavenger hunts, and games to demonstrate the vector cycle. Potential domiciliary breeding sites were significantly reduced; the proportion of houses without breeding sites was significantly increased; and there was an increase in the percentage of individuals who recognized the larval form of the vector in the study area as compared to the control area.  相似文献   
100.
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