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11.
Media reports have described recreational use of HIV antiretroviral medication in South Africa, but little has been written about this phenomenon in the scientific literature. We present original, qualitative data from eight semi-structured interviews that characterize recreational antiretroviral use in Soweto, South Africa. Participants reported that antiretrovirals, likely efavirenz, are crushed, mixed with illicit drugs (in a mixture known as whoonga), and smoked. They described medications being stolen from patients and expressed concern that antiretroviral abuse jeopardized the safety of both patients and users. Further studies are needed to understand the prevalence, patterns, and consequences of antiretroviral abuse and diversion.  相似文献   
12.
Introduction: Low-back disorders (LBDs) are the most common musculoskeletal problem among farmers, with higher prevalence rates than in other occupations. Farmers who operate tractors and other types of machinery can have substantial exposure to whole-body vibration (WBV). Although there appears to be an association between LBDs and WBV, the causal relationship is not clear. Objective: This scoping review investigates the association between WBV and LBDs specifically among farmers. Methods: Nine databases were searched using groups of terms for two concepts: ‘farming’ and ‘low back disorder’. Screening, data extraction, and quality assessment were performed by two reviewers independently. Included studies met the following criteria: focused on adult farmers/agricultural workers; assessed exposure to operating farm machinery such tractor, combine, or all-terrain vehicle; assessed LBDs as an outcome; and reported an inferential test to assess the relationship between WBV and LBD. Results: After 276 full texts screened, 11 articles were found to analyze WBV as a risk factor for LBDs. Three were case–control, five cross-sectional, and three retrospective cohorts. Four studies showed no association between WBV and LBDs, four a positive association, and three results were mixed depending on the exposure/outcome measure. Conclusion: A firm conclusion is difficult due to heterogeneity in, LBDs definition, type of farm commodity, study design, and statistical strategy. Direct comparisons and synthesis were not possible. Although retrospective cohort studies tended to show a relationship, future studies with a prospective cohort design could help clarify this association further.  相似文献   
13.
Primary intraosseous synovial sarcoma is an extremely rare malignancy that occurs primarily in young adults. We present a case of a primary intraosseous synovial sarcoma of the right distal ulna in a 19-year-old female. It has a propensity to mimic other radiologic and pathologic diagnosis. Histopathology after a surgical excisional biopsy with a wide margin plus adjunct radio and chemotherapy are necessary to improve prognosis.  相似文献   
14.
Background: People consume nitrates, nitrites, nitrosamines, and NOCs compounds primarily through processed food. Many studies have yielded inconclusive results regarding the association between cancer and dietary intakes of nitrates and nitrites. This study aimed to quantify these associations across the reported literature thus far. Methods: We performed a systematic review following PRISMA and MOOSE guidelines. A literature search was performed using Web of Science, Embase, PubMed, the Cochrane library, and google scholar up to January 2020. STATA version 12.0 was used to conduct meta-regression and a two-stage meta-analysis. Results: A total of 41 articles with 13 different cancer sites were used for analysis. Of these 13 cancer types/sites, meta-regression analysis showed that bladder and stomach cancer risk was greater, and that pancreatic cancer risk was lower with increasing nitrite intakes. Kidney and bladder cancer risk were both lower with increasing nitrate intakes. When comparing highest to lowest (reference) categories of intake, meta-analysis of studies showed that high nitrate intake was associated with an increased risk of thyroid cancer (OR = 1.40, 95% CI: 1.02, 1.77). When pooling all intake categories and comparing against the lowest (reference) category, higher nitrite intake was associated with an increased risk of glioma (OR = 1.12, 95% CI: 1.03, 1.22). No other associations between cancer risk and dietary intakes of nitrates or nitrites were observed. Conclusion: This study showed varied associations between site-specific cancer risks and dietary intakes of nitrate and nitrite. Glioma, bladder, and stomach cancer risks were higher and pancreatic cancer risk was lower with higher nitrite intakes, and thyroid cancer risk was higher and kidney cancer risk lower with higher nitrate intakes. These data suggest type- and site-specific effects of cancer risk, including protective effects, from dietary intakes of nitrate and nitrite.  相似文献   
15.
ABSTRACT. The present study was designed to validate and standardize a short psychomotor screening test on Australian four-year-old-preschool children and to assess their home environment using Caldwell's HOME Inventory. The Adelaide Psychomotor Screen (APS) is a short, 10--15 minute screening test which uses 13 separate items to assess "General" development, "Gross Motor" development, "Social/Emotional Behaviour" and "Speech".
In the area of "General" development, 12 children screened as "abnormal" and 54 children screened as "normal" were further assessed by a psychologist on the McCarthy Scales of Children's Abilities. There was a high correlation between the APS "General" scores and the McCarthy (General Cognitive Index) scores (r = 0.75, p<0.001 for the younger children, and r = 0,90, p <0.001 for the older children).
Caldwell's HOME Inventory takes an hour to complete, and involves a visit by the assessor to each home. The correlation between the HOME total scores and the McCarthy (General Cognitive Index) scores was r =0.06, p < 0.001. It is suggested that the HOME Inventory may be more valuable as a predictor of a child's future development than an index of his present developmental status.
It is suggested that nurses and teachers used the APS as a screening test of the individual child, and use the HOME inventory as an assessment of the home environment.  相似文献   
16.
Pharmacokinetics of chloroquine: saliva and plasma levels relationship   总被引:1,自引:0,他引:1  
The use of saliva levels as an alternative to plasma levels in monitoring chloroquine therapy was studied in five healthy volunteers. Subjects took two (250 mg) tablets of chloroquine diphosphate (300 mg chloroquine base) with 200 ml of water. Saliva and blood samples were collected at intervals over 6 days. Plasma was separated from blood samples after centrifugation while saliva samples were centrifuged to remove mucoid sediments. Both the plasma and saliva samples were analysed for chloroquine by a combination of thin-layer chromatography and spectrophotometry. Regression analysis was used to determine the correlation between saliva and plasma chloroquine levels. A significant correlation (r = 0.97, p less than 0.05) was observed between saliva and plasma levels of chloroquine. The saliva: plasma concentrations ratio was found to be 0.53. From the saliva: plasma relationship, the extent of chloroquine binding to plasma proteins was estimated to be 47%. The Cmax and AUC0-6 day values obtained from saliva data was about half those from plasma, while the Tmax obtained from both fluids remained the same. The saliva clearance rate (Cls/F) of chloroquine was about twice the plasma clearance rate (Cl/F). (Cls/F: 0.46 +/- 0.051/day/kg; 0.27 +/- 0.021/day/kg). However, the predicted Cl/F (0.27 +/- 0.031/day/kg) from saliva data was in agreement with Cl/F from plasma data. This was also true of the volume of distribution. The collection of saliva for measuring chloroquine levels provides a painless, non-invasive alternative to plasma sampling, and it is useful in predicting chloroquine pharmacokinetics.  相似文献   
17.
Ten healthy, male volunteers (aged 19-27 yr; weight 62-67 kg) were randomly distributed into control and test groups of five subjects each in a controlled study on the effect of ranitidine on chloroquine disposition. The control group subjects received two tablets of chloroquine sulfate (300-mg base) only. The test group subjects received ranitidine 250 mg hs for four days prior to the administration of chloroquine sulfate and throughout the sample collection period. Blood samples (5 ml) were collected from the time of the chloroquine administration to the seventh day after drug administration. The samples were analyzed for chloroquine content by a combination of thin-layer chromatography and ultraviolet spectrophotometry. The Wilcoxon test at 0.05 significance level was used to compare the disposition parameters between control and test groups. Ranitidine therapy was associated with no significant alterations in chloroquine oral clearance rate, elimination rate constant, and apparent volume of distribution. Unlike cimetidine, ranitidine does not interact pharmacokinetically with chloroquine. Ranitidine, therefore, may be the H2-receptor antagonist of choice for ulcer patients receiving chloroquine.  相似文献   
18.
Uniformed services personnel are at an increased risk of HIV infection. We examined the HIV/AIDS knowledge and sexual risk behaviors among female military personnel to determine the correlates of HIV risk behaviors in this population. The study used a cross-sectional design to examine HIV/AIDS knowledge and sexual risk behaviors in a sample of 346 females drawn from two military cantonments in Southwestern Nigeria. Data was collected between 2006 and 2008. Using bivariate analysis and multivariate logistic regression, HIV/AIDS knowledge and sexual behaviors were described in relation to socio-demographic characteristics of the participants. Multivariate logistic regression analysis revealed that level of education and knowing someone infected with HIV/AIDS were significant (P < 0.05) predictors of HIV knowledge in this sample. HIV prevention self-efficacy was significantly (P < 0.05) predicted by annual income and race/ethnicity. Condom use attitudes were also significantly (P < 0.05) associated with number of children, annual income, and number of sexual partners. Data indicates the importance of incorporating these predictor variables into intervention designs.  相似文献   
19.
In this study a qualitative approach is used to investigate relevant beliefs and norms concerning the consumption, initiation, and perceived addiction of codeine and promethazine hydrochloride cough syrup (CPHCS) among 61 college-age students who identified themselves as current CPHCS users. In general, a majority of students stated that doctors and pharmacists were the greatest facilitators of CPHCS acquisition. A majority of students believed that their friends felt codeine promethazine use was "normal" and "cool" among college students their age, and that reinforcing factors, such as peer pressure and curiosity, contributed to initial CPHCS use.  相似文献   
20.
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