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101.
Human infection by leptospires has highly variable clinical manifestations, which range from subclinical infection to fulminant disease. We conducted a population-based, cross-sectional seroepidemiologic study in Peru to determine potential relationships of environmental context to human exposure to Leptospira and disease associated with seroconversion. Three areas were studied: a flooded, urban slum in the Peruvian Amazon city of Iquitos; rural, peri-Iquitos villages; and a desert shantytown near Lima. Seroprevalence in Belen was 28% (182/650); in rural areas, 17% (52/316); and in a desert shantytown, 0.7% (1/150). Leptospira-infected peridomestic rats were found in all locales. In Belen, 20 (12.4%) of 161 patients seroconverted between dry and wet seasons (an incidence rate of 288/1,000). Seroconversion was associated with history of febrile illness; severe leptospirosis was not seen. Human exposure to Leptospira in the Iquitos region is high, likely related both to the ubiquity of leptospires in the environment and human behavior conducive to transmission from infected zoonotic sources.  相似文献   
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STUDY OBJECTIVE: To investigate the association between multiple indicators of socioeconomic status (SES) over the life course and three stages of cigarette use: initiation, regular use, and cessation. DESIGN: Prospective birth cohort study. SETTING: Providence, Rhode Island. PARTICIPANTS: Subjects (n=657) aged 30 to 39 were offspring of participants in the Brown University cohort of the United States National Collaborative Perinatal Project started in 1959. MAIN RESULTS: A significantly increased risk of smoking initiation was observed among people from lower socioeconomic backgrounds. Low SES in childhood also increased the risk for progression to regular smoking, and was associated with a reduced likelihood of smoking cessation. Progression to regular smoking and smoking persistence were also associated with lower adult SES. CONCLUSIONS: Socioeconomic conditions over the life course accumulate to produce increased rates of smoking uptake and reduced rates of cessation among lower SES people. Addressing SES gradients in smoking will require persistent and extended intervention over multiple life stages.  相似文献   
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Helicobacter pylori (HP) infection can cause hypochlorhydria, a positive risk factor for Mycobacterium tuberculosis (MTB) infection. This study examined the association between HP and MTB infections among persons attending the Policlinico Peruano Japonés Gastrointestinal Clinic in Lima, Peru. From 23 June 2000 to 18 August 2000, consenting 18-55 year olds who attended the clinic for gastric biopsy gave blood for HP serologic testing, underwent tuberculin skin testing (TST) and completed a social and medical history. Of 128 participating patients, 78 (61%) were TST positive for MTB, and 107 (84%) were infected with HP by serology. Of the patients who were HP positive, 67 (63%) developed positive TST reactions compared to 11 (52%) of 21 HP-seronegative subjects (OR 1.29; 95% CI 0.54-3.11; P = 0.6). There was no association after adjusting for covariates of H. pylori infection (OR 0.78; 95% CI 0.23-2.71; P = 0.7). However, study power was limited by high prevalence of the two infections.  相似文献   
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A recently described one-day regimen of praziquantel (PZQ) therapy for neurocysticercosis (NCC), three doses of 25 mg/k given at 2 h intervals, was applied in eight patients with viable NCC cysts without any evidence of inflammation. Resolution of lesions in computed tomography (CT) was observed in all five patients with a single cyst, whereas all cysts survived in three patients with multiple brain parasites. One-day praziquantel is a good regimen for patients with a single viable brain cysticercus but is poorly effective for multiple cysts.  相似文献   
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During 1998, the Department of Health proposed to use survival rates of cervical and breast cancer in the 1989/90 incidence cohort as indicators of care. Valid interpretation was of concern within Trent and the Trent Cancer Registry responded by performing additional analyses. Trent Cancer Registry registrations for 1989/90 were re-analysed and the stability of districts' ranks for that cohort was investigated using random simulation techniques. Stability of ranks across more recent cohorts was investigated and attempts made to use all available information.The Department of Health's analyses were confirmed by our re-analysis of the 1989/90 cohort: Rotherham residents appeared to have the "worst" survival for cervical cancer, and Sheffield residents for breast cancer, although not statistically significantly so. Random simulations indicated that ranks based on a single cohort are not stable: for example Sheffield (ranked tenth for 1-y breast cancer survival) was ranked third or better in 6% of randomisations. Ranks were also unstable across cohorts: for example Rotherham 1-y cervical cancer survival was ranked tenth for 1989/90, fifth for 1991/92 and tenth for 1993/94. Analysis of 3-y running averages provided better information than the league table approach. Most districts improved over time, to different degrees, and similar sized gaps remained between the "best" and the "worst" districts. This analysis illustrates the need to be circumspect when interpreting "league tables" based on a single year or cohort analysis. League tables are based on ranks: clearly a large difference in rank may reflect only trivial (ie medically unimportant) differences in actual outcome. Lack of a statistically significant difference in survival between two districts does not mean their survival is equivalent. Even for a common cancer, like breast cancer, rankings were unstable from cohort to cohort. At the Registry we propose to perform these trend analyses routinely in future, adjusting, when possible, for the effects of deprivation and stage at diagnosis.  相似文献   
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OBJECTIVES: This study examined the risk of psychiatric disorders among individuals with same-sex sexual partners. METHODS: Data are from the National Comorbidity Survey, a nationally representative household survey. Respondents were asked the number of women and men with whom they had sexual intercourse in the past 5 years. Psychiatric disorders according to Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (DSM-III-R) criteria were assessed with a modified version of the Composite International Diagnostic Interview. RESULTS: A total of 2.1% of men and 1.5% of women reported 1 or more same-sex sexual partners in the past 5 years. These respondents had higher 12-month prevalences of anxiety, mood, and substance use disorders and of suicidal thoughts and plans than did respondents with opposite-sex partners only. Decomposition showed that the elevated same-sex 12-month prevalences were largely due to higher lifetime prevalences. Ages at onset and persistence of disorders did not differ between the same-sex and opposite-sex subsamples. CONCLUSIONS: Homosexual orientation, defined as having same-sex sexual partners, is associated with a general elevation of risk for anxiety, mood, and substance use disorders and for suicidal thoughts and plans. Further research is needed to replicate and explore the causal mechanisms underlying this association.  相似文献   
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In this study, a behavioral intervention known as the STD/HIV Intervention Program (SHIP) was implemented at the Navy preventive medicine technician (PMT) school as a "train-the-trainer" course. Course evaluation questionnaires were administered to PMT students immediately after the training. Follow-up interviews evaluating the SHIP course were conducted with PMTs (N = 73) 1 year after the training. PMT students were fairly satisfied with SHIP overall, as well as with specific components of the course. As hypothesized, the SHIP train-the-trainer course was considered useful by most PMTs in their first duty assignments after completing PMT school.  相似文献   
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