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81.

Objective

To investigate the roles of physical activity (exercise) and sociodemographic factors in depressive symptoms among men and women in the United States.

Data Source

2011 U.S. Behavioral Risk Factor Surveillance System (BRFSS).

Study Design

Patient Health Questionnaire Depression Scale (PHQ-8) scores are aggregated and divided into five categories. An ordered switching probability model with binary endogenous physical activity is developed to accommodate ordinality of depression categories and ameliorate statistical biases due to endogeneity of physical activity.

Principal Findings

Average treatment effects suggest physical activity ameliorates depressive symptoms among mildly and moderately depressed individuals, most notably among mildly depressed women. Gender differences exist in the roles of sociodemographic factors, with age, income, race, education, employment status, and recent mental health condition playing differentiated roles in affecting depressive symptoms.

Conclusions

Regular physical activity reduces depressive symptoms among both men and women with mild to moderate depression, notably among women.  相似文献   
82.

Objective

To evaluate the current evidence of the effectiveness of dry needling of myofascial trigger points (MTrPs) associated with low back pain (LBP).

Data Sources

PubMed, Ovid, EBSCO, ScienceDirect, Web of Science, Cochrane Library, CINAHL, and China National Knowledge Infrastructure databases were searched until January 2017.

Study Selection

Randomized controlled trials (RCTs) that used dry needling as the main treatment and included participants diagnosed with LBP with the presence of MTrPs were included.

Data Extraction

Two reviewers independently screened articles, scored methodologic quality, and extracted data. The primary outcomes were pain intensity and functional disability at postintervention and follow-up.

Data Synthesis

A total of 11 RCTs involving 802 patients were included in the meta-analysis. Results suggested that compared with other treatments, dry needling of MTrPs was more effective in alleviating the intensity of LBP (standardized mean difference [SMD], ?1.06; 95% confidence interval [CI], ?1.77 to ?0.36; P=.003) and functional disability (SMD, ?0.76; 95% CI, ?1.46 to ?0.06; P=.03); however, the significant effects of dry needling plus other treatments on pain intensity could be superior to dry needling alone for LBP at postintervention (SMD, 0.83; 95% CI, 0.55–1.11; P<.00001).

Conclusions

Moderate evidence showed that dry needling of MTrPs, especially if associated with other therapies, could be recommended to relieve the intensity of LBP at postintervention; however, the clinical superiority of dry needling in improving functional disability and its follow-up effects still remains unclear.  相似文献   
83.
Two studies have concluded that lithium exposure extends the lifespan of Caenorhabditis elegans. However, the effect of lithium on another widely used model organism, Drosophila melanogaster, remains unclear. Here, we demonstrate that chronic treatment with a low to moderate dose of lithium chloride does not extend lifespan in D. melanogaster and that the drug abolishes the female lifespan advantage in flies.  相似文献   
84.
PurposeEating disorders and their core symptoms (eg, binge eating, body weight/shape concerns) disproportionately affect females, and these sex-differentiated effects become prominent during and after puberty. Although psychosocial influences such as heightened sociocultural pressures for thinness in girls and women contribute to this sex imbalance, biological factors could also play an important role.MethodsThis narrative review summarizes evidence of biological factors underlying the sex-differentiated prevalence of eating pathology as well as within-sex variability in risk.FindingsThere are sex differences in the pubertal emergence of genetic effects on eating pathology (adrenarche in males; gonadarche in females), and at least some genetic contributions to eating pathology seem to vary between the sexes. Furthermore, sex steroid hormones (eg, testosterone, estradiol, progesterone) are leading contributors to differential risk for eating pathology in males and females across the life span. Emerging data suggest that between-sex and within-sex variability in risk might occur via hormone-driven modulation (activation/deactivation) of genetic influences and neural responsiveness to food-related cues.ImplicationsThere is a biological basis to heightened risk for eating pathology in females, relative to males, as well as unique biological influences within each sex. Findings from this review highlight the importance of studying both sexes and considering sex-specific biological mechanisms that may underlie differential risk for eating pathology  相似文献   
85.
BackgroundIndividuals with lower limb amputation are routinely assessed with a variety outcome measures, however there is a lack of published data to indicate minimal clinically important differences (MCID) for many of these outcome measures. Three such important gait-specific outcome measures include walking velocity, gait profile score (GPS) and the two minute walk test (2MWT).Research questionDetermine the MCIDs for walking velocity, GPS and 2MWT for individuals with lower limb amputation.MethodsWalking velocity and GPS (n = 60), and 2MWT (n = 119) data for individuals with unilateral transfemoral or knee disarticulation were identified retrospectively from a database held at the study centre. An anchor-based method was used with Medicare functional classification level (MFCL) acting as the impairment-related criterion, and a least-squares linear regression approach was used to calculate the gradient required for a change between MFCL levels.ResultsAn increase of 0.21 m/s (95 % CI: 0.13,0.29) for walking velocity, a reduction of 1.7° (95 % CI: -2.449,-1.097) for GPS and an increase of 37.2 m (95 % CI: 28.8,45.5) for 2MWT were found to correspond to an increase in MFCL of one level. Walking velocity, GPS and 2MWT correlated with MFCL with R2 values of 0.333, 0.322 and 0.398 respectively (p < 0.00001). The authors propose that 0.21 m/s for walking velocity, 1.7° for GPS and 37.2 m for 2MWT be used as MCID values for individuals with lower limb amputation.SignificanceThe results of this study can be used to help both researchers and clinicians to objectively evaluate if interventions for individuals with lower limb amputation are effective.  相似文献   
86.
Schizophrenia (SCZ) is a highly heterogeneous disorder with remarkable intersubject variability in clinical presentations. Previous neuroimaging studies in SCZ have primarily focused on identifying group-averaged differences in the brain connectome between patients and healthy controls (HCs), largely neglecting the intersubject differences among patients. We acquired whole-brain resting-state functional MRI data from 121 SCZ patients and 183 HCs and examined the intersubject variability of the functional connectome (IVFC) in SCZ patients and HCs. Between-group differences were determined using permutation analysis. Then, we evaluated the relationship between IVFC and clinical variables in SCZ. Finally, we used datasets of patients with bipolar disorder (BD) and major depressive disorder (MDD) to assess the specificity of IVFC alteration in SCZ. The whole-brain IVFC pattern in the SCZ group was generally similar to that in HCs. Compared with the HC group, the SCZ group exhibited higher IVFC in the bilateral sensorimotor, visual, auditory, and subcortical regions. Moreover, altered IVFC was negatively correlated with age of onset, illness duration, and Brief Psychiatric Rating Scale scores and positively correlated with clinical heterogeneity. Although the SCZ shared altered IVFC in the visual cortex with BD and MDD, the alterations of IVFC in the sensorimotor, auditory, and subcortical cortices were specific to SCZ. The alterations of whole-brain IVFC in SCZ have potential implications for the understanding of the high clinical heterogeneity of SCZ and the future individualized clinical diagnosis and treatment of this disease.  相似文献   
87.
Sex differences in the structure and organization of the corpus callosum (CC) can be attributed to genetic, hormonal or environmental effects, or a combination of these factors. To address the role of gonadal hormones on axon myelination, functional axon conduction and immunohistochemistry analysis of the CC in intact, gonadectomized and hormone‐replaced gonadectomized animals were used. These groups were subjected to cuprizone diet‐induced demyelination followed by remyelination. The myelinated component of callosal compound action potential was significantly decreased in ovariectomized and castrated animals under normal myelinating condition. Compared to gonadally intact cohorts, both gonadectomized groups displayed more severe demyelination and inhibited remyelination. Castration in males was more deleterious than ovariectomy in females. Callosal conduction in estradiol‐supplemented ovariectomized females was significantly increased during normal myelination, less attenuated during demyelination, and increased beyond placebo‐treated ovariectomized or intact female levels during remyelination. In castrated males, the non‐aromatizing steroid dihydrotestosterone was less efficient than testosterone and estradiol in restoring normal myelination/axon conduction and remyelination to levels of intact males. Furthermore, in both sexes, estradiol supplementation in gonadectomized groups increased the number of oligodendrocytes. These studies suggest an essential role of estradiol to promote efficient CC myelination and axon conduction in both sexes.  相似文献   
88.
目的以阿胶为例探讨"补血"功效的中西医内涵。方法通过文献检索,从阿胶补血功效的历史记载,中西医"血"本质探讨,中医"血虚证"与西医"贫血"的关系,中西医治疗缺血常见药物比较以及阿胶补血的现代内涵,5方面进行文献分析归纳。结果阿胶补血功效古今均有记载,被历代临床所证实;中西医"血"的概念本质不同;中医"血虚证"与西医"贫血"概念不同;中西医治疗缺血常见药物的现代研究具明显区别;阿胶补血功效存在现代药理研究基础。结论中西医"补血"概念存在本质区别,大众应正确认识中西医补血功效的不同,正视阿胶补血功效。  相似文献   
89.
90.
The opinion of mind–body interaction has been increasingly acknowledged in recent years, as exemplified by accumulating evidence indicating that physical health (body) is associated with emotion and emotion regulation (mind). Yet, the neural basis linking emotion regulation with physical health remains largely uninvestigated. Here we used magnetic resonance imaging to investigate the neural basis of this pathway in a large population of healthy young adults. With a systematic study revealing the association of self-reported physical health and emotion traits of personality and general affective experiences, we further demonstrated that, for better physical health, individuals needed to regulate their emotion more effectively. Importantly, individuals who had larger gray matter (GM) volume in the amygdala reported not only a higher ability of emotion regulation but also better physical health. Further, GM volume in the amygdala mediated the correlation between emotion regulation ability and physical health. Our findings suggest that the amygdala plays a critical role in the neural circuit through which emotion regulation may influence physical health. Therefore, our study takes the first step toward exploring the neuroanatomical basis for body–mind interaction and may inform interventions aimed at promoting physical health by augmenting skills of emotion regulation.  相似文献   
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