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1.
In an urban school district, 636 students in grades 9-12 were tested for Chlamydia trachomatis and Neisseria gonorrhoeae by ligase chain reaction assays using specimens collected for routine urinalyses during sports physical examinations. Chlamydia and gonorrhea prevalences were 2.8% and 0.7% among males, and 6.5% and 2.0% among females, respectively. Among athletes infected with either sexually transmitted disease (STD), 93.1% reported no symptoms, and treatment was documented for 75.9%. Sports physicals offered a unique opportunity to screen and treat adolescents for STDs and to provide STD-prevention counseling.  相似文献   
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The efficacy of an oral formulation of praziquantel (Equitape, Horse paste, Fort Dodge) in the reduction of cestode egg counts and serum antibody level against Anoplocephala perfoliata was assessed in 44 donkeys under field conditions. The donkeys were confirmed both by faecal examination and serum antibody assessed by an enzyme-linked immunosorbent assay to have natural infection with tapeworms. The donkeys were randomly allocated into treatment (n?=?22) and control (n?=?22) groups. The treatment group was treated with both praziquantel and ivermectin (Ivomec, Merial) at a dose rate of 1 mg/kg and 200 μg/kg, respectively while the control group was treated only with ivermectin. Faecal samples were collected before treatment (day-0) and 2, 6, 8, 12, and 16 weeks post-treatment while blood samples were collected before treatment and 8 and 16 weeks after treatment and analysed. The results of the study demonstrated that praziquantel paste was highly effective in reducing cestode eggs in donkeys and had an efficacy of more than 99 % until week 16 (day?112). No cestode egg reappearance by 16 weeks post-treatment in any animal in the treatment group was observed while donkeys in the control group continued shedding cestode eggs. The immunological assay also showed a significant reduction in serum antibody level against A. perfoliata in treated donkeys compared to the control group (p?=?0.0001). This marked decrease in serum antibody level indicates reduced risk of cestode-associated colic and other gastrointestinal disorders and clinical diseases. No adverse reactions or clinical effects were encountered in any animal within either group throughout the trial period.  相似文献   
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The vascular effects of ionizing radiation were examined in K1735 murine melanoma tumors. Single-fraction and fractionated radiation virtually arrested growth of these tumors for about a week, after which they resumed more rapid growth. Tumor microvessel density (MVD) and blood perfusion was unchanged seven days after radiation but decreased at later time points after irradiation, when they had grown 10-fold or more. Together with the finding of severe tumor hypoxia and VEGF induction in the latter tumors, the evidence pointed to vascular insufficiency and inhibited neovascularization in tumors that had grown substantially after radiation. Endothelial cell (EC) death detected by TUNEL staining only transiently increased the day following radiation, whereas EC proliferation detected by Ki-67 staining was increased in irradiated tumors that had grown substantially. The fact that increased EC proliferative activity produced fewer vessels suggests that angiogenesis is defective or ineffective after radiation. These results complement recent genetic evidence that EC damage from radiation plays a major role in tissue damage and antitumor efficacy to highlight the importance of EC and vasculature in radiation response. Our studies further show that radiation impact on tumor vasculature extends beyond near-term induction of EC death to more prolonged effects on their ability to support angiogenesis.  相似文献   
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Objectives To investigate xanthine oxidase (XO) polymorphism in Ethiopians and influence of environmental factors, smoking habit and gender-related differences on enzyme activity among Ethiopians living in Ethiopia or Sweden.Methods One hundred healthy unrelated Ethiopians living in Ethiopia and 73 living in Sweden participated in the study. Subjects received a 100-mg oral dose of caffeine before bedtime. All urine voided in the following 8 h was collected and the concentrations of 1-methyluracil (1U) and 1-methylxanthine (1X) (mol/l) were analyzed by means of high-performance liquid chromatography. The 1U/(1X+1U) metabolic ratio (MR) was calculated and used as an index of XO activity.Results XO activity was not normally distributed (P<0.0001; Shapiro-Wilk's test). The incidence of putative XO poor metabolizers in Ethiopians was 4%. The effect of differences in country of residence, gender and smoking habit was analyzed using three-way ANOVA/MANOVA. The post-hoc test (P<0.05) and Kruskal-Wallis ANOVA (P<0.004), median test showed a significant difference in XO activity among Ethiopians living in Ethiopia compared with those living in Sweden, the activity being higher in Ethiopians living in Ethiopia. The 95% CI for differences between the two means was (0.012; 0.044). No significant difference was observed in XO MR between men and women or between smokers and non-smokers, the 95% CI for the differences being (–0.059; 0.037) and (–0.010; 0.016) respectively.Conclusion The XO activity is polymorphic in Ethiopians. Neither gender nor smoking-related differences influenced XO activity but the difference in activity between Ethiopians living in Sweden or in Ethiopia indicates influence of other environmental factors such as dietary habits on XO activity.  相似文献   
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OBJECTIVE: Evaluation and monitoring of Human Immunodeficiency Virus (HIV) testing reagents at the point of service is helpful to prevent the occurrence of problems related to testing and interpretation. To evaluate the implementation of HIV rapid test kits at the point of services in voluntarily counseling and testing (VCT) and diagnostic centers in Ethiopia. METHODS: The assessment was the third phase of evaluation of HIV rapid test kits in Ethiopia followed from phase-I and phase-II. Known proficiency testing panels, well-structured questionnaire (addressing type of tests, human resource and problems related to tests), onsite supervision and retesting of samples collected from sites were used to evaluate the performances of reagents and laboratories. RESULTS: Forty-four health institutions were included. Thirty-six (90.0%) health institutions had trained human resource on HIV testing. In 27 (61.4%) three types of HIV rapid test kits (Determine, Capillus and Unigold) were available. Serial-algorithm was used in all the laboratories. In 31 (70.4%) of them external quality control specimens were not used. Twenty two (50.0%) of the laboratories reported frequent shortage of reagents. All (100%) were able to identify negative specimens distributed. Positive proficiency panel samples were identified in 37 (94.8%) of the 39 laboratories. There was 98.3% agreement at a screening level between the sites and the central laboratory. Rate of discrepancy between screening and confirmatory assays was found to be 3.0% and 2.1% at the sites and at central laboratory, respectively. CONCLUSION: The test kits showed a good performance at the point of services in the field sites. However, continuous assessment of HIV test kits at the point of service and training of professionals on newly arrived techniques are recommended to have effective testing performance with acceptable sensitive and specific testing algorithm. Effective quality assurance program should be in place to support programs such as VCT, prevention of mother-to-child-transmission and antiretroviral therapy.  相似文献   
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Summary. A one-year birth cohort was studied in Jimma town, South West Ethiopia, in 1992-93. We report here on the design and on the methods used in the study and describe the principal health outcomes. Infants were visited bimonthly until their first birthday. Background data on the physical, cultural and economic environment of the home were collected at the first visit, and data on nursing and weaning, on traditional surgical and other practices, and on vaccination at the first visit and at each subsequent visit. Length, weight and mid upper arm circumference were measured, and details of the mother's handling of illness episodes recorded. Of 1563 children born, 86% were successfully followed to the end of their first year or to an earlier death. There were 141 deaths, indicating an infant mortality of 115/1000 (estimated probability of surviving to 1 year 0.8851, with s.e. 0.0101). The mean length and weight of the singleton infants at the end of their first year was -1.41 and - 1.52SD from the median of the NCHS/WHO reference population. Weights throughout the first year were analysed in more detail using a Reed model, fitted as a random coefficient regression model in ML3-E. There were clear differences in growth across the different ethnic groups, with the best growing group weighing on average about l kg more at the end of the first year than the groups growing least well.  相似文献   
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Experiments showed that the intraoral iodide permeability (Ip) method can be used in a reproducible and sensitive manner with solid foods. Ingestion of 5-gram portions of cookies made with defined concentrations of sucrose or fat led to an increased Ip (due to demineralization) of Streptococcus mutans-covered bovine enamel blocks in vivo. Demineralization increased with time to a maximum of 45 min, and the pH of the plaque dropped accordingly. Continued exposure in the mouth beyond 45 min led to an elevation of the pH and a decrease in delta Ip consistent with remineralization of the enamel. Control blocks worn without ingestion of cookies exhibited negative delta Ip values. Demineralization increased with increasing sucrose content of the cookies and reached a plateau when cookies containing 1.08 g sucrose per morsel were administered. Cookies prepared without added sucrose gave a high delta Ip. High fat content raised the delta Ip when sucrose was low. These findings are consistent with clinical and other observations, and emphasize the complex relation between foods and enamel demineralization.  相似文献   
10.
This study identified factors that are associated with dental fluorosis among school adolescents in an endemic area using a control design. Data were collected using a directed self-administered questionnaire. Dental fluorosis was confirmed by a dentist. Out of the 472 students who participated in the study, 398 had dental fluorosis and the remaining 74 were free of dental fluorosis. A logistic regression analysis revealed children born in Wonji compared to those born elsewhere [Adjusted OR (95% CI): 5.12 (2.68, 9.75)]; males compared to female [Adjusted OR (95% CI): 2.76 (1.52, 5.00)]; and those who obtained their regular drinking water from pipe distribution compared to those who obtained water from other sources [Adjusted OR (95% CI): 3.5 (1.24, 10.02] were more likely to have dental fluorosis. Students in the age group 13-14 year compared to those in 11-12 year were less likely to have dental fluorosis [Adjusted OR (95% CI): 0.43 (0.25, 0.76)]. The findings indicate that the risk of dental fluorosis is still much higher for the population in Wonji and recommend strengthening appropriate intervention systems at household and community levels.  相似文献   
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