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1.
Over 36 million people worldwide are infected with HIV. Antiretroviral therapy (ART) has proven to be highly effective to prevent HIV-1 transmission, clinical progression and death. Despite this success, the number of HIV-1 infected individuals continues increasing and ART should be taken for life. Therefore, there are two main priorities: the development of preventive vaccines to protect from HIV acquisition and achieve an efficient control of HIV infection in the absence of ART (functional cure). In this sense, in the last few years, there has been a broad interest in new and innovative approaches such as mRNA-based vaccines. RNA-based immunogens represent a promising alternative to conventional vaccines because of their high potency, capacity for rapid development and potential for low-cost manufacture and safe administration. Some mRNA-based vaccines platforms against infectious diseases have demonstrated encouraging results in animal models and humans. However, their application is still limited because the instability and inefficient in vivo delivery of mRNA. Immunogens, design, immunogenicity, chemical modifications on the molecule or the vaccine delivery methods are all crucial interventions for improvement. In this review we, will present the current knowledge and challenges in this research field. mRNA vaccines hold great promises as part of a combined strategy, for achieving HIV functional cure.  相似文献   
2.
Fetal scalp blood sampling (FSBS), in conjunction with fetal heart rate monitoring, is a method of fetal surveillance that may avoid cesarean delivery of the healthy fetus or indicate the need for immediate delivery of a compromised fetus. Some researchers have recently begun to question the efficacy of FSBS. In this article, three nurse-midwives discuss FSBS as a tool in assessing fetal well-being during labor and consider whether FSBS is a nurse-midwifery procedure.  相似文献   
3.
Immunologic and pharmacologic concepts of monoclonal antibodies   总被引:2,自引:0,他引:2  
While monoclonal antibodies have solved many of the difficulties of using immunologic reagents for radioimmunodiagnosis and therapy, in the 13 years since their introduction a number of persistent problems remain, most notably a low yield of antibody-producing cells from the fusion process, difficulty in obtaining high-affinity antibodies, and the potential immunogenicity of murine immunoglobulins (Igs). Several solutions are under development, including fusion techniques that enrich for cells producing desired antibodies, production of human-mouse chimeric antibodies by recombinant DNA technology, and the generation of human monoclonal antibodies by promising new approaches. Until these upcoming methodologies are established, and to better direct their development and application, a sound understanding of the pharmacology of presently available native and modified monoclonal antibodies is crucial. Although much has been already determined in this area, a great deal of further clarification remains necessary.  相似文献   
4.
Background: This is the second of two papers using qualitative methods from a study of an intervention for family members affected by close relatives' substance misuse problems.

Participants: 168 primary healthcare professionals (PHCPs: GPs, practice nurses and health visitors) working in general practices in two areas of England, and who took part in the study.

Data sources: Recruitment and post-session forms completed by PHCPs; telephone interviews with each PHCP 12 weeks after recruitment of a family member; interviews with PHCPs at the end of the study.

Results: At the end of the project PHCPs were overwhelmingly positive about the family member intervention and about primary care as the appropriate site. Difficulties were encountered, however, in identifying and engaging affected family members, who were often excluded on grounds of the complexity of their problems or the level of their distress. Shortage of PHCP time and other practice-related factors added to the difficulty. Active work by a PHCP was often necessary in order to make the link between presenting symptoms of physical or mental ill-health and the existence of a family substance misuse problem. When family members were identified and recruited, PHCPs were usually positive about what was achieved. Nearly all were in favour of an approach that combined giving a self-help manual with some follow-up contact with a family member as needed.

Conclusions: Taken in conjunction with statistical outcome findings of significant reductions in symptoms and changes in ways of coping, plus qualitative analysis of the views of family members, the present results encourage the view that a flexible form of this intervention should be developed for use in primary healthcare, and that further work should build on existing strengths and attempt to overcome weaknesses identified.  相似文献   
5.
Government reform of the NHS in the UK has sought to increase the involvement of doctors (clinicians) in hospital management. Using frameworks from the psychological contract and organisational misbehaviour literatures, this paper examines the processes involved when clinicians assume management roles. This literature seeks to explain breaches to expectations regarding prior agreements with management and subsequent actions of 'getting even' as a result of breaches to the employment relationship. A qualitative methodology using interviews was undertaken, which identified two distinct groups of clinician-manager. Investors actively pursued a management opportunity as an alternative to clinical medicine, whilst reluctants tended to assume a management role to protect particular specialities from outside influence or from those they thought would be inappropriate clinician-managers. Investors and reluctants often had very little prior experience of management and managers and had problems reconciling their dual clinician-management role. Poor relationships with hospital managers who often had no understanding of their dual responsibilities led to tensions and conflict, which questions continued developments in this important area of UK health policy. Suggestions for improving this process are outlined.  相似文献   
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The Minnesota Heart Health Program (MHHP) is a research and demonstration project of population-wide primary prevention of cardiovascular disease. Study goals are to achieve reductions in cardiovascular disease risk factors and morbidity and mortality in three education communities compared with three reference communities. The program in the first of the three intervention communities, Mankato, has been operating for 3 of the planned 5 years. Early objectives of the program have been achieved based on data obtained from population-based random samples surveyed in education and comparison communities. After 2 years of participation, Mankato was significantly more exposed to activities promoting cardiovascular disease prevention. In this town of 38,000 inhabitants, 190 community leaders were directly involved as program volunteers, 14,103 residents (over 60% of adults) attended a screening education center, 2,094 attended MHHP health education classes, 42 of 65 physicians and 728 other health professionals participated in continuing education programs offered by MHHP, and distribution of printed media averaged 12.2 pieces per household. These combined educational strategies have resulted in widespread awareness of MHHP and participation by the majority of the Mankato adult population in its education activities.  相似文献   
9.
It has been inferred that residue changes that affect T cell recognition of synthetic peptides will have a similar effect in the intact protein. However, since small peptides do not require antigen processing it is possible that residue changes in synthetic peptides will not have an equivalent effect in the intact protein. Mutant proteins of staphylococcal nuclease (Nase) and 15mer synthetic peptides with corresponding substitutions were compared to determine if residue changes within an immunodominant epitope have an effect on the generation of naturally processed peptides. Five different substitutions in the synthetic peptide resulted in loss of reactivity of individual Nase-specific clones. When the same single amino acid changes were made in the intact protein, the naturally-processed peptides were also unable to stimulate the Nase-specific clones. However, two other substitutions in the synthetic peptide were stimulatory for a T cell clone even though the same changes in the intact protein were non-stimulatory. These results suggest that certain residue changes affect recognition of the naturally processed peptide but not the synthetic peptide with the same amino acid change. In addition, these results demonstrate that the effects of amino acid substitutions in synthetic peptides on T cell recognition may not always reflect the effects of these substitutions in the intact protein. Substitutions located outside Nase-specific T cell epitopes were also examined. Thirty different mutant proteins were all stimulatory. Moreover, a number of these mutants proteins were 50- to 100-fold more efficient in their stimulatory capacity than the native Nase protein.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Clinical studies suggest that deprenyl may retard the progression of Parkinson's disease, an effect that may be related to its monoamine oxidase (MAO) inhibiting properties. Deprenyl also protects against the neurodegenerative effects of the noradrenergic toxin DSP-4. In this study we investigated the role of MAO B inhibition in this protection. C57BL/6 mice were given DSP-4 (50 mg/kg i.p.) 1 h. 24 h or 4 days after the administration of deprenyl (10 mg/kg i.p.) or the selective MAO B inhibitor MDL 72974 (1.25 mg/kg), and then killed 1 week later for assay of hippocampal norepinephrine. The MAO B inhibiting effects of deprenyl or MDL 72974 were also determined after these same intervals of time. Deprenyl and MDL 72974 produced comparable degrees of enzyme inhibition 1 h (greater than 95%), 24 h (greater than 90%) or 4 days (greater than 70%) after their administration. Given 1 h before, deprenyl totally blocked the norepinephrine-depleting effects of DSP-4, but this protection declined sharply when 24 h or 4 days was allowed to elapse between deprenyl and DSP-4 administration. MDL 72974 failed to protect at any time point. In vitro, we detected no activity using DSP-4 as a substrate for MAO. These findings suggest that the ability of deprenyl to protect against DSP-4-induced neuronal degeneration may not depend on its MAO B inhibiting properties.  相似文献   
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