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151.
Hypersensitivity pneumonitis (HP) is an immunoallergic disease characterized by a prominent interstitial infiltrate composed predominantly of lymphocytes secreting inflammatory cytokines. Dendritic cells (DCs) are known to play a pivotal role in the lymphocytic response. However, their cross talk with microorganisms that cause HP has yet to be elucidated. This study aimed to investigate the initial interactions between human monocyte-derived DCs (MoDCs) and four microorganisms that are different in nature (Saccharopolyspora rectivirgula [actinomycetes], Mycobacterium immunogenum [mycobacteria], and Wallemia sebi and Eurotium amstelodami [filamentous fungi]) and are involved in HP. Our objectives were to determine the cross talk between MoDCs and HP-causative agents and to determine whether the resulting immune response varied according to the microbial extract tested. The phenotypic activation of MoDCs was measured by the increased expression of costimulatory molecules and levels of cytokines in supernatants. The functional activation of MoDCs was measured by the ability of MoDCs to induce lymphocytic proliferation and differentiation in a mixed lymphocytic reaction (MLR). E. amstelodami-exposed (EA) MoDCs expressed higher percentages of costimulatory molecules than did W. sebi-exposed (WS), S. rectivirgula-exposed (SR), or M. immunogenum-exposed (MI) MoDCs (P < 0.05, Wilcoxon signed-rank test). EA-MoDCs, WS-MoDCs, SR-MoDCs, and MI-MoDCs induced CD4+ T cell proliferation and a Th1-polarized immune response. The present study provides evidence that, although differences were initially observed between MoDCs exposed to filamentous fungi and MoDCs exposed to bacteria, a Th1 response was ultimately promoted by DCs regardless of the microbial extract tested.  相似文献   
152.
OBJECTIVE:: To assess hospitalization trends in HIV-infected children on antiretroviral therapy (ART) in Thailand, an important indicator of morbidity, ART effectiveness, and health service utilization. DESIGN:: Prospective observational cohort METHOD:: Children initiating ART in 1999-2009 were followed in 40 public hospitals. Hospitalization rate per 100 person-years were calculated from ART initiation to last follow-up/death. Costs to the healthcare provider were calculated using WHO inpatient estimates for Thailand. Zero-inflated Poisson models were used to examine risk factors for early (<12 months of ART) and late hospitalization (≥12 months) and frequency of admissions. RESULTS:: A total of 578 children initiated ART, median follow-up being 64 months [interquartile range (IQR) 43-82]; 211 (37%) children were hospitalized with 451 admissions. Hospitalization rates declined from 63 per 100 person-years at less than 6 months to approximately 10 per 100 person-years after 2 years of ART, and costs fell from $35 per patient-month to under $5, respectively. Age less than 2 years, US Centers of Disease Control and Prevention stage B/C, and stunting at ART initiation were associated with early hospitalization. Among those hospitalized, baseline CD4 cell percentage less than 5%, wasting, initiation on dual therapy, late calendar year, and female sex were associated with higher incidence of early admissions (P?<0.02). There were no predictors of late hospitalization, although previous hospitalization in less than 12 months of ART was associated with three times higher incidence of late admissions (P?相似文献   
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In Hamburg, Germany, the initiation of HIV post-exposure prophylaxis (HIV PEP) in cases of sexual violence is often carried out by forensic medical specialists (FMS) using the city’s unique Hamburg Model. FMS-provided three-day HIV PEP starter packs include a combination of raltegravir and emtricitabine/tenofovir. This study aimed to investigate the practice of offering HIV PEP, reasons for discontinuing treatment, patient compliance, and whether or not potential perpetrators were tested for HIV. We conducted a retrospective study of forensic clinical examinations carried out by the Hamburg Department of Legal Medicine following incidents of sexual violence from 2009 to 2016. One thousand two hundred eighteen incidents of sexual violence were reviewed. In 18% of these cases, HIV PEP was initially prescribed by the FMS. HIV PEP indication depended on the examination occurring within 24 h after the incident, no/unknown condom use, the occurrence of ejaculation, the presence of any injury, and the perpetrator being from population at high risk for HIV. Half of the HIV PEP recipients returned for a reevaluation of the HIV PEP indication by an infectious disease specialist, and just 16% completed the full month of treatment. Only 131 potential perpetrators were tested for HIV, with one found to be HIV positive. No HIV seroconversion was registered among the study sample. Provision of HIV PEP by an FMS after sexual assault ensures appropriate and prompt care for victims. However, patient compliance and completion rates are low. HIV testing of perpetrators must be carried out much more rigorously.  相似文献   
155.
Rare earth atoms exhibit several interesting properties, for example, large magnetic moments and luminescence. Introducing these atoms into a different matrix can lead to a material that shows multiple interesting effects. Holmium atoms were incorporated into an iron oxide nanoparticle and the concentration of the dopant atom was changed in order to determine its influence on the host crystal. Its magnetic and magneto-optical properties were investigated by vibrating sample magnetometry and Faraday rotation measurements. The luminescent characteristics of the material, in solution and incorporated in a polymer thin film, were probed by fluorescence experiments.  相似文献   
156.
Some individuals exhibit a weak satiety response to food and may be susceptible to overconsumption. The current study identified women showing consistently low or high satiety responses to standardised servings of food across four separate days and compared them on behavioural, psychological and physiological risk factors for overeating and future weight gain. In a crossover design, 30 female participants (age: 28.0 ± 10.6; body mass index (BMI): 23.1 ± 3.0) recorded sensations of hunger in the post-prandial period following four graded energy level breakfasts. Satiety quotients were calculated to compare individuals on satiety responsiveness across conditions. Body composition, resting metabolic rate (RMR), energy intake, food reward and craving, and eating behaviour traits were assessed under controlled laboratory conditions. A distinct low satiety phenotype (LSP) was identified with good consistency across separate study days. These individuals had a higher RMR, greater levels of disinhibition and reported feeling lower control over food cravings. Further, they consumed more energy and exhibited greater wanting for high-fat food. The inverse pattern of characteristics was observed in those exhibiting a consistently high satiety phenotype (HSP). Weak satiety responsiveness is a reliable trait identifiable using the satiety quotient. The LSP was characterised by distinct behavioural and psychological characteristics indicating a risk for overeating, compared to HSP.  相似文献   
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Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, whereas in the test group solid feed was provided. Maternal antibodies for alpha toxin were present in 45% of the veal calves and 66% of the beef calves. In beef calves a fluent transition from maternal to active immunity was observed for alpha toxin, whereas almost no veal calves developed active immunity. Perfringolysin antibodies significantly declined both in veal and beef calves. In the second study all calves were seropositive for alpha toxin throughout the experiment and solid feed intake did not alter the dynamics of alpha and perfringolysin antibodies. In conclusion, the present study showed that veal calves on a traditional milk replacer diet had significantly lower alpha toxin antibodies compared to beef calves in the risk period for enterotoxaemia, whereas no differences were noticed for perfringolysin.  相似文献   
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