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ContextFear has been cited as the primary barrier to return to sport (RTS) by athletes after anterior cruciate ligament reconstruction (ACLR). Understanding the neural factors that contribute to fear after ACLR may help us to identify interventions for this population.ObjectiveTo characterize the underlying neural substrate of injury-related fear in patients after ACLR versus healthy matched control individuals during a picture imagination task (PIT) consisting of sport-specific images and images of activities of daily living (ADL).DesignCase-control study.SettingResearch laboratory.Patients or Other ParticipantsA total of 24 right-hand–dominant participants (12 with left-sided ACLR and 12 control individuals) were enrolled. Participants underwent full-brain functional magnetic resonance imaging.Main Outcome Measure(s)Functional data were acquired using blood oxygen level–dependent (BOLD) echoplanar imaging. Independent t tests were conducted to identify between-groups differences in BOLD signal changes during all images of the PIT. Paired t tests were computed to examine differences in BOLD signal change between sport-specific and ADL images in the ACLR group.ResultsIncreased activation in the inferior parietal lobule and the mediodorsal thalamus was observed during PIT in the ACLR group. An inability to suppress the default mode network in the ACLR group was noted. The ACLR group exhibited increased activation in the cerebellum and inferior occipital regions during the sport-specific images versus the ADL images, but no other regions of interest demonstrated differences.ConclusionAfter ACLR, patients may be more predisposed to fear, anxiety, and pain during sport-specific activities and ADLs. Psychosocial interventions may be warranted after ACLR to reduce injury-related fear and mitigate potentially maladaptive neuroplasticity.  相似文献   
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OBJECTIVE: To analyze the fine specificity of IgG autoantibodies in sera from rheumatoid arthritis (RA) patients for type II collagen (CII) epitopes that are arthritogenic in collagen-induced arthritis (CIA), a relevant murine model of RA. METHODS: For enzyme-linked immunosorbent assay (ELISA) analysis of conformation-dependent autoantibody binding, recombinant chimeric collagens that harbor the respective CII epitopes as an insertion within the frame of a constant type X collagen triple helix were constructed. In addition, synthetic peptides mimicking the native collagen structures were applied for the first time in the ELISA assessment of humoral CII autoimmunity. RESULTS: The pathogenicity of IgG responses to certain CII determinants in CIA was demonstrated by arthritis development in BALB/c mice upon the combined transfer of 2 mouse monoclonal antibodies specific for precisely mapped conformational CII epitopes (amino acid residues 359-369 [C1(III)] and 551-564 [J1]), whereas antibodies to another epitope (F4) were not arthritogenic. To test whether human autoimmune responses are similarly directed to these conserved CII determinants, serum IgG was analyzed. The prevalence of sera with increased IgG binding to the C1(III) epitope was significantly higher in RA compared with sera from healthy donors or from patients with other rheumatic conditions, e.g., osteoarthritis (OA), systemic lupus erythematosus (SLE), or relapsing polychondritis (RP), whereas levels of antibodies specific for the nonarthritogenic F4 epitope were associated with OA rather than RA. CONCLUSION: Autoimmunity to CII, although detectable in different rheumatic conditions, differs in fine specificity between distinct disease entities. In RA, in contrast to degenerative joint disease, RP, and SLE, autoantibody responses are directed to an evolutionary conserved CII structure that is also targeted by pathogenic autoimmune responses in murine models of arthritis.  相似文献   
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In the context of the shortage of resources to close the alarming treatment gap of mental disorders, interventions to promote mental health have become a priority of policy makers in low and middle-income countries (LMICs) like India. In this paper, we document an attempt to identify key strategies to promote positive mental health of young people in the state of Kerala, India. Our results could be used for integrating the concept of positive mental health into public health interventions in the state. Focus group discussions among different groups of stakeholders were used to gather information about their attitudes, perceptions or opinions followed by a Delphi exercise involving policy-makers and experts to come to a consensus approach. In-depth exploration of possible policy options was made possible with the participation of experts in related fields using qualitative techniques. Findings from this qualitative study suggest that a life cycle approach may be helpful in identifying areas for possible effective policy interventions for promoting mental health in young people. Improving education and employment opportunities at a macro-level will have a positive impact on mental health. In conclusion, the promotion of mental health among young people should find a prominent place in health policies at national level.  相似文献   
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Ultrasmall superparamagnetic iron oxide nanoparticles (USPION) possess reactive surfaces, are metabolized and exhibit unique magnetic properties. These properties are desirable for designing novel theranostic biomedical products; however, toxicity mechanisms of USPION are not completely elucidated. The goal of this study was to investigate cell interactions (uptake and cytotoxicity) of USPION using human coronary artery endothelial cells as a vascular cell model. Polyvinylpirrolidone-coated USPION were characterized: average diameter 17 nm (transmission electron microscopy [TEM]), average hydrodynamic diameter 44 nm (dynamic light scattering) and zeta potential −38.75 mV. Cells were exposed to 0 (control), 25, 50, 100 or 200 μg/mL USPION. Concentration- and time-dependent cytotoxicity were observed after 3-6 hours through 24 hours of exposure using Alamar Blue and Real-Time Cell Electronic Sensing assays. Cell uptake was evaluated by imaging using live-dead confocal microscopy, actin and nuclear fluorescent staining, and TEM. Phase-contrast, confocal microscopy, and TEM imaging showed significant USPION internalization as early as 3 hours after exposure to 25 μg/mL. TEM imaging demonstrated particle internalization in secondary lysosomes with perinuclear localization. Three orthogonal assays were conducted to assess apoptosis. TUNEL staining demonstrated a marked increase in fragmented DNA, a response pathognomonic of apoptosis, after a 4-hour exposure. Cells subjected to agarose gel electrophoresis exhibited degraded DNA 3 hours after exposure. Caspase-3/7 activity increased after a 3-hour exposure. USPION uptake resulted in cytotoxicity involving apoptosis and these results contribute to further mechanistic understanding of the USPION toxicity in vitro in cardiovascular endothelial cells.  相似文献   
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Mammals develop in a physiologically hypoxic state, and the oxygen tension of different tissues in the embryo is precisely controlled. Deviation from normal oxygenation, such as what occurs in placental insufficiency, can disrupt fetal development. Several studies demonstrate that intrauterine hypoxia has a negative effect on kidney development. As nascent nephrons are forming from nephron progenitors in the nephrogenic zone, they are exposed to varying oxygen tension by virtue of the development of the renal vasculature. Thus, nephrogenesis may be linked to oxygen tension. However, the mechanism(s) by which this occurs remains unclear. This review focuses on what is known about molecular mechanisms active in physiological and pathological hypoxia and their effects on kidney development.  相似文献   
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Little is known about the therapeutic processes contributing to efficacy of psychological interventions for patients with cancer. Data from a randomized clinical trial yielding robust biobehavioral and health effects (B. L. Andersen et al., 2004, 2007) were used to examine associations between process variables, treatment utilization, and outcomes. Novel findings emerged. Patients were highly satisfied with the treatment, but their higher levels of felt support (group cohesion) covaried with lower distress and fewer symptoms. Also, specific treatment strategies were associated with specific outcomes, including lower distress, improved dietary habits, reduced symptomatology, and higher chemotherapy dose intensity. These data provide a comprehensive test of multiple therapeutic processes and mechanisms for biobehavioral change with an intervention including both intensive and maintenance phases.  相似文献   
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Children with autism spectrum disorder (ASD) and their families may benefit from the provision of additional supports in health care settings, particularly when preparing for and attending medical appointments. This review examined literature that describes experiences in medical care settings from the perspective of patients under age 18 with ASD and their caregivers. A scoping review was conducted to examine the experiences of children with ASD and their families in medical care settings. Twenty‐nine studies meeting inclusion criteria were identified and reviewed. The review indicated a number of challenges (e.g., parent‐reported problems in parent‐provider communication and overwhelming environments) as well as factors that facilitate positive experiences (e.g., providing positive reinforcement and explaining exam steps) during medical appointments. Children with ASD and their families are faced with many challenges while receiving care in medical settings. The present review identified many challenges families face, as well as facilitators of positive experiences. Understanding the unique experiences of patients with ASD and their parents will help to improve experiences in medical care settings for children, caregivers, and health care providers.  相似文献   
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