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Child undernutrition is responsible for 45% of all under-five deaths in low- and middle-income countries (LMICs) and numerous morbidities. Although progress has been made, high levels of child undernutrition persist in Zambia. Existing studies have explored primary caretakers' (PCs) explanatory models of child undernutrition in LMICs, without comparison with those of health care providers (HCPs). This paper examines and compares the perceived causes of child undernutrition among PCs and HCPs in Zambia. We conducted a qualitative study, using semistructured one-to-one and group interviews, with 38 PCs and 10 HCPs to explore their perceptions of child undernutrition and its perceived causes in Lusaka district, Zambia. Interview data were analysed with thematic analysis. Our findings indicate that PCs and HCPs in Lusaka district have divergent explanatory models of child undernutrition and perceive parental agency differently. In divergently framing how they conceptualise undernutrition and who is able to prevent it, these models underpin different attributions of causality and different opportunities for intervention. PCs highlighted factors such as child food preferences, child health, and household finances. Contrarily, HCPs stressed factors such as ‘improper feeding’, only highlighting factors such as wider economic conditions when these impacted specifically on health care services. One factor, identified by both groups, was ‘inadequate mothering’. To accelerate the reduction of child undernutrition, interventions must address divergences between PCs and HCPs' explanatory models. Additionally, attention needs to be paid to how wider socio-economic and cultural contexts not only impact childhood undernutrition but shape attributions of causality.  相似文献   
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An IgM antibody capture assay for detection of cytomegalovirus (CMV) IgM antibody (MACRIA) was developed. It was shown to be of similar sensitivity to the indirect immunofluorescence test but has the advantage that rheumatoid factor does not react in it and pretest fractionation of serum is not required. It does, however, give false results with some Paul Bunnell-positive sera. The assay was used to measure the IgM response in 28 renal transplant patients followed prospectively. Seven patients (100%) with primary infections and six of 13 (46%) patients with secondary infections developed IgM by MACRIA. Nine of 13 (69%) patients with CMV IgM-positive sera had symptoms other than pyrexia associated with CMV infections, while only one of seven (14%) IgM-negative infections were symptomatic. Four of seven irreversible rejection episodes were associated with CMV IgM. The possible significance of CMV IgM production is discussed.  相似文献   
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We present two children discovered to have a total cataract in one eye with a posterior subcapsular cataract in the other eye. Sequential photography documented rapid progression of the posterior subcapsular cataract to a preexisting posterior capsule defect and subsequently to a white, mature cataract. We propose that early intervention be considered in cases with any posterior subcapsular changes (no matter how subtle) and history of total cataract in the fellow eye, especially in any situation where loss of follow-up is likely to occur. In the event surgery is not advised, parents should be warned about possible cataract progression and the importance of regular follow-up examinations.  相似文献   
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BACKGROUND: The independent influence of childhood social circumstances on health in later life remains uncertain. We examined the extent to which childhood socio-economic circumstances are related to the risk of coronary heart disease (CHD) in older British men, taking account of adult social class and behavioural risk factors. METHODS: A socio-economically representative sample of 5552 British men (52-74 years) with retrospective assessment of childhood socio-economic circumstances (father's occupation and childhood household amenities) who were followed up for CHD (fatal and non-fatal) for 12 years. RESULTS: Men whose childhood social class was manual had an increased hazard ratio (HR) 1.34 (95% CI 1.11-1.63)-this effect was diminished when adjusted for adult social class and adult behavioural risk factors (cigarette smoking, alcohol, physical activity and body weight) (HR 1.19; 95% CI 0.97-1.46). Men whose family did not own a car in their childhood were at increased CHD risk even after adjustments for adult social class and behaviours (HR 1.35, 95% CI 1.04-1.75). Men with combined exposure to both childhood and adult manual social class had the highest risk of CHD (HR 1.51; 95% CI 1.19-1.91); this was substantially reduced by adjustment for adult behavioural risk factors (adjusted HR 1.28; 95% CI 0.99-1.65). CONCLUSIONS: Less affluent socio-economic conditions in childhood may have a modest persisting influence on risk of CHD in later life.  相似文献   
78.
Evidence-based practice is an increasingly popular term, used in a variety of clinical settings and situations. Practitioners are encouraged to use best evidence as part of clinical decision-making when caring for individual patients. This evidence, combined with practitioner expertise and knowledge, aims to inform practice, ensuring that accurate, effective and safe treatment options are utilized.  相似文献   
79.
Nucleation of protein fibrillation by nanoparticles   总被引:2,自引:0,他引:2  
Nanoparticles present enormous surface areas and are found to enhance the rate of protein fibrillation by decreasing the lag time for nucleation. Protein fibrillation is involved in many human diseases, including Alzheimer's, Creutzfeld-Jacob disease, and dialysis-related amyloidosis. Fibril formation occurs by nucleation-dependent kinetics, wherein formation of a critical nucleus is the key rate-determining step, after which fibrillation proceeds rapidly. We show that nanoparticles (copolymer particles, cerium oxide particles, quantum dots, and carbon nanotubes) enhance the probability of appearance of a critical nucleus for nucleation of protein fibrils from human beta(2)-microglobulin. The observed shorter lag (nucleation) phase depends on the amount and nature of particle surface. There is an exchange of protein between solution and nanoparticle surface, and beta(2)-microglobulin forms multiple layers on the particle surface, providing a locally increased protein concentration promoting oligomer formation. This and the shortened lag phase suggest a mechanism involving surface-assisted nucleation that may increase the risk for toxic cluster and amyloid formation. It also opens the door to new routes for the controlled self-assembly of proteins and peptides into novel nanomaterials.  相似文献   
80.
We present a detailed structural characterization of the intermediate state populated during the folding and unfolding of the bacterial immunity protein Im7. We achieve this result by incorporating a variety of experimental data available for this species in molecular dynamics simulations. First, we define the structure of the exchange-competent intermediate state of Im7 by using equilibrium hydrogen-exchange protection factors. Second, we use this ensemble to predict Phi-values and compare the results with the experimentally determined Phi-values of the kinetic refolding intermediate. Third, we predict chemical-shift measurements and compare them with the measured chemical shifts of a mutational variant of Im7 for which the kinetic folding intermediate is the most stable state populated at equilibrium. Remarkably, we found that the properties of the latter two species are predicted with high accuracy from the exchange-competent intermediate that we determined, suggesting that these three states are characterized by a similar architecture in which helices I, II, and IV are aligned in a native-like, but reorganized, manner. Furthermore, the structural ensemble that we obtained enabled us to rationalize the results of tryptophan fluorescence experiments in the WT protein and a series of mutational variants. The results show that the integration of diverse sets of experimental data at relatively low structural resolution is a powerful approach that can provide insights into the structural organization of this conformationally heterogeneous three-helix intermediate with unprecedented detail and highlight the importance of both native and non-native interactions in stabilizing its structure.  相似文献   
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