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71.
Peer victimization is associated with several mental health and behavioral problems during childhood and adolescence. Identifying prospective associations between victimization and factors known to protect against these problems may ultimately contribute to more precise developmental models for victimization’s role in behavioral and mental health. This study tested prospective associations between peer victimization and dispositional mindfulness, defined by non-judgmental and accepting awareness of the constant stream of lived experience, during early adolescence. It was hypothesized that victimization would predict lower levels of mindfulness over a 4-month period. Study participants were 152 seventh and eighth grade students (female?=?51%, Caucasian?=?35%, Hispanic/Latino?=?34%, African-American?=?13%, and multi-ethnic or other?=?18%) participating in a social-emotional learning intervention feasibility trial. A structural equation model tested associations between mindfulness, victimization, and covariates at baseline, and mindfulness and victimization at 4-month posttest. As hypothesized, baseline victimization predicted significantly lower levels of mindfulness at 4-month posttest. Baseline mindfulness did not predict victimization. Results may reflect victimized youths’ mindful awareness being recurrently diverted away from the present moment due to thoughts of prior and/or impending victimization. Study implications may include implementing mindful awareness practices as an intervention strategy for victimized youth to enhance and/or restore this promotive factor.  相似文献   
72.
Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a physical and cognitive disabling illness, characterized by severe fatigue and a range of physiological symptoms, that primarily affects women. The immense variation in clinical presentation suggests differences in severity based on symptomology and physical and cognitive functional capacities. In this article, we examine a number of severity scales used in assessing severity of patients with CFS/ME and the clinical aspects of CFS/ME severity subgroups. The use of severity scales may be important in CFS/ME because it permits the establishment of subgroups that may improve accuracy in both clinical and research settings.  相似文献   
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74.

Integrative Data Analysis (IDA) encompasses a collection of methods for data synthesis that pools participant-level data across multiple studies. Compared with single-study analyses, IDA provides larger sample sizes, better representation of participant characteristics, and often increased statistical power. Many of the methods currently available for IDA have focused on examining developmental changes using longitudinal observational studies employing different measures across time and study. However, IDA can also be useful in synthesizing across multiple randomized clinical trials to improve our understanding of the comprehensive effectiveness of interventions, as well as mediators and moderators of those effects. The pooling of data from randomized clinical trials presents a number of methodological challenges, and we discuss ways to examine potential threats to internal and external validity. Using as an illustration a synthesis of 19 randomized clinical trials on the prevention of adolescent depression, we articulate IDA methods that can be used to minimize threats to internal validity, including (1) heterogeneity in the outcome measures across trials, (2) heterogeneity in the follow-up assessments across trials, (3) heterogeneity in the sample characteristics across trials, (4) heterogeneity in the comparison conditions across trials, and (5) heterogeneity in the impact trajectories. We also demonstrate a technique for minimizing threats to external validity in synthesis analysis that may result from non-availability of some trial datasets. The proposed methods rely heavily on latent variable modeling extensions of the latent growth curve model, as well as missing data procedures. The goal is to provide strategies for researchers considering IDA.

  相似文献   
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Rib cage morphology changes with age and sex are expected to affect thoracic injury mechanisms and tolerance, particularly for vulnerable populations such as pediatrics and the elderly. The size and shape variation of the external geometry of the ribs was characterized for males and females aged 0–100 years. Computed tomography (CT) scans from 339 subjects were analyzed to collect between 2700 and 10 400 homologous landmarks from each rib. Rib landmarks were analyzed using the geometric morphometric technique known as Procrustes superimposition. Age‐ and sex‐specific functions of 3D rib morphology were produced representing the combined size and shape variation and the isolated shape variation. Statistically significant changes in the size and shape variation (< 0.0001) and shape variation (< 0.0053) of all 24 ribs were found to occur with age in males and females. Rib geometry, location, and orientation varied according to the rib level. From birth through adolescence, the rib cage experienced an increase in size, a decrease in thoracic kyphosis, and inferior rotation of the ribs relative to the spine within the sagittal plane. From young adulthood into elderly age, the rib cage experienced increased thoracic kyphosis and superior rotation of the ribs relative to the spine within the sagittal plane. The increased roundedness of the rib cage and horizontal angling of the ribs relative to the spine with age influences the biomechanical response of the thorax. With the plane of the rib oriented more horizontally, loading applied in the anterior‐posterior direction will result in increased deformation within the plane of the rib and an increased risk for rib fractures. Thus, morphological changes may be a contributing factor to the increased incidence of rib fractures in the elderly. The morphological functions derived in this study capture substantially more information on thoracic skeleton morphology variation with age and sex than is currently available in the literature. The developed models of rib cage anatomy can be used to study age and sex variations in thoracic injury patterns due to motor vehicle crashes or falls, and clinically relevant changes due to chronic obstructive pulmonary disease or other diseases evidenced by structural and anatomic changes to the chest.  相似文献   
77.
78.
Objective: Examine connections between mothers’ adult attachment and subjective birth experience in the context of parity and mode of delivery.

Background: Research has established a clear connection between adult attachment and birth experience. This study extended previous research with an in-depth self-report attachment measure examining different dimensions of mothers’ attachment representations and their relation to subjective birth experience. Interactions between mode of delivery and parity were also considered. Method: Participants were 257 mothers who gave birth 4 days to 12 months prior to the study. Mothers’ mean age was 30.5 years, 61% primiparas, and 26% delivered by caesarean. Participants completed an online survey with the Birth Experience Questionnaire, the Reciprocal Attachment Questionnaire, and demographic information.

Results: Hierarchical moderated regression analyses showed direct effects from adult attachment dimensions to mothers’ subjective birth experiences, specifically perceived availability, feared loss, separation protest, angry withdrawal, and compulsive careseeking. Interactions emerged for parity and/or mode of delivery for overall subjective birth experience, perceived control, perceived social support, and satisfaction.

Conclusion: Adult attachment representations related to subjective birth experience, indicating that attachment figures serve as secure bases and safe havens for mothers during childbirth. These results have implications for practitioners and provide direction for future research.  相似文献   

79.
Objective: This study aimed to investigate a flaxseed diet during different developmental periods, and its effect on the blood pressure of rats submitted to stress.

Methods: Fifty-six male rats (F1), born from 14 rats (F0), were divided into seven groups (n?=?8): flaxseed group (FG); flaxseed group gestation and lactation (FG-GL); flaxseed group weaning (FG-W); flaxseed group weaning and stress (FG-WS); flaxseed group stress (FG-S); flaxseed group gestation lactation and weaning (FG-GLW), and control Group (CG). Stress protocol was undertaken for 1 month. Blood pressure was analysed before and after the stress protocol. The left adrenal glands and serum corticosterone levels were analysed.

Results: Systolic blood pressure before stress was lower in all groups with flaxseed diet compared with the CG (p?=?.00001). After stress, CG showed higher blood pressure compared with FG, FG-GL, and FG-GLW (p?=?.004). The levels of corticosterone were lower in the FG between all groups (p?p?Conclusions: Results suggest a possible factor from a flaxseed diet against the effects of stress on a blood pressure in all periods of life but especially in the gestation and lactation periods.  相似文献   
80.
Wronski  Samantha L.  Mordin  Margaret  Kelley  Kim  Anguiano  Rebekah H.  Classi  Peter  Shen  Eric  Manaker  Scott 《Lung》2020,198(1):65-86
Background

Until recently, many clinical trials in patients with pulmonary arterial hypertension (PAH) evaluated exercise capacity with 6-minute walk distance (6MWD) as the primary endpoint. Common secondary endpoints include PAH functional class (FC), which assesses symptoms, and either brain natriuretic peptide (BNP) or the inactive N-terminal cleavage product of its prohormone (NT-proBNP), which assesses cardiac function.

Objective

Examine the relationships among 6MWD, FC, and BNP/NT-proBNP measured at baseline or follow-up with long-term outcomes in PAH studies.

Methods

Relevant literature from January 1990 to April 2018 were obtained by searching PubMed, Embase, and Cochrane. Articles in English reporting on associations between 6MWD, FC, or BNP/NT-proBNP and outcomes in PAH were identified. Each endpoint was evaluated individually. Prespecified inclusion and exclusion criteria were applied at level 1 (titles/abstracts) and level 2 (full-text review).

Results

The database search yielded 836 unique records; 65 full-text articles were reviewed. Twenty-five studies were eligible for inclusion. Findings supported the importance of measuring PAH noninvasive endpoints in predicting long-term outcomes. Patients with shorter or decreased 6MWD, poor (III/IV) or declining FC (e.g., from II to III), or elevated or increasing BNP/NT-proBNP had a higher risk of death and costly events (e.g., hospitalization, lung transplant). FC also predicted health care resource utilization and costs. Collectively, these endpoints establish risk groups that predict likelihood of complications from PAH or death.

Conclusion

Assessment of 6MWD, FC, and BNP/NT-proBNP provides low-cost, efficient, and noninvasive means of predicting long-term health and economic outcomes in patients with PAH.

  相似文献   
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