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51.
Artemether (ART) is a well-described antimalarial with efficacy against juvenile schistosomes, with 7-day-old schistosomula being particularly susceptible. Both ART-affected worms and parasites developing from irradiated cercariae die at similar times after infection. Our aim was to determine if ART treatment of prepatent schistosomiasis japonica may result in the generation of a protective immune response. Female CBA mice were treated with a single dose of ART at defined time points after percutaneous infection with a virulent Chinese mainland strain of Schistosoma japonicum. Half of the mouse cohorts were subjected to homologous parasite strain reinfection after drug treatment to assess protective effects of ART therapy. Two independent trials demonstrated that a statistically significant (58% and 50%) reduction in challenge worm burden occurred after reinfection of those mice treated with ART at two weeks p.i. A reduction in the IL-4 response to soluble worm antigen preparation (SWAP) was also seen in ART-treated mice but with no correlation to reinfection resistance. In the Chinese mainland strain used, ART treatment of prepatent infection at the appropriate time point induced resistance to reinfection. There was also an anti-pathology effect observed in ART-treated mice that remained significant after reinfection.  相似文献   
52.

Objective

We investigated correlations between residents’ scores on the Jefferson Scale of Empathy (JSE), residents’ perceptions of their empathy during standardized-patient encounters, and the perceptions of standardized patients.

Methods

Participants were 214 first-year residents in internal medicine or family medicine from 13 residency programs taking standardized patient-based clinical skills assessment in 2011. We analyzed correlations between residents’ JSE scores; standardized patients’ perspectives on residents’ empathy during OSCE encounters, using the Jefferson Scale of Patient Perceptions of Physician Empathy; and residents’ perspectives on their own empathy, using a modified version of this scale.

Results

Residents’ JSE scores correlated with their perceptions of their own empathy during encounters but correlated poorly with patients’ assessments of resident empathy.

Conclusion

The poor correlation between residents’ and standardized patients’ assessments of residents’ empathy raises questions about residents’ abilities to gauge the effectiveness of their empathic communications. The study also points to a lack of congruence between the assessment of empathy by standardized patients and residents as receivers and conveyors of empathy, respectively.

Practice implications

This study adds to the literature on empathy as a teachable skill set and raises questions about use of OSCEs to assess trainee empathy.  相似文献   
53.
A 74-year old man underwent a radical cholecystectomy for presumed gallbladder cancer. The histology of the resected specimen in fact revealed the lesion to be metastatic renal cell carcinoma from his resected right nephrectomy performed 14 years previously.  相似文献   
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Brain‐derived neurotrophic factor (BDNF) is implicated in the pathophysiology of major depression; mice lacking BDNF expression through promoter IV (BDNF‐KIV) exhibit a depression‐like phenotype. We tested our hypothesis that deficits caused by promoter IV deficiency (depression‐like behavior, decreased levels of BDNF, and neurogenesis in the hippocampus) could be rescued by a 3‐week treatment with different types of antidepressants: fluoxetine, phenelzine, duloxetine, or imipramine. Each antidepressant reduced immobility time in the tail suspension test without affecting locomotor activity in the open field test in both BDNF‐KIV and control wild type mice, except that phenelzine increased locomotor activity in wild type mice and anxiety‐like behavior in BDNF‐KIV mice. The antidepressant treatments were insufficient to reverse decreased BDNF levels caused by promoter IV deficiency. No antidepressant treatment increased the hippocampal progenitors of either genotype, whereas phenelzine decreased the surviving progenitors in both genotypes. The antidepressant treatments differently affected the dendritic extension of hippocampal immature neurons: fluoxetine and imipramine increased extension in both genotypes, duloxetine increased it only in BDNF‐KIV mice, and phenelzine decreased it only in wild type mice. Interestingly, a saline‐only injection increased neurogenesis and dendrite extensions in both genotypes. Our results indicate that the behavioral effects in the tail suspension test by antidepressants do not require promoter IV‐driven BDNF expression and occur without a detectable increase in hippocampal BDNF levels and neurogenesis but may involve increased dendritic reorganisation of immature neurons. In conclusion, the antidepressant treatment demonstrated limited efficacy; it partially reversed the defective phenotypes caused by promoter IV deficiency but not hippocampal BDNF levels.  相似文献   
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Purpose

The aim of this study is to compare implantation and live birth rates (LBR) between fresh euploid embryo transfers versus cryo-all cycles with a subsequent embryo transfer into a prepared endometrium.

Material and Methods

This is a retrospective cohort study. Patients who underwent an IVF cycle with PGS with trophectoderm biopsy from January 2011 to July 2015 were included. Patients were divided into three groups: “Fresh Only,” “Frozen Embryo Transfer ('FET) Only,” and “Fresh ET then FET.” For “Fresh Only” group (n = 345), PGS results were received within 24 h. For “FET Only” group (n = 514), results were expected after 24 h, and embryos were cryopreserved after biopsy; only FET was performed in this group (no fresh transfer). For “FET with a previous fresh ET” (n = 139) group, patients underwent a fresh ET with a subsequent FET, in which the same cohort of embryos was utilized. The main outcome measures were pregnancy rate (PR), clinical PR, implantation rate (IR), LBR, and early pregnancy loss rate.

Results

IRs were statistically higher in the “FET Only” group when compared to the “Fresh Only” group (59.5 vs. 50.6 %, p < 0.01) and the “FET with a previous fresh ET” (59.5 vs. 50.6 %, p < 0.05). LBR was statistically significant in the “FET Only” group when compared to the “Fresh Only” group (57.6 vs. 46.5 %, p < 0.005) but not when compared to “FET with a previous fresh ET” group (57.6 vs. 47.7 %, p = 0.07).

Conclusions

This analysis suggests euploid embryos to be more likely to implant and achieve a LBR in a synthetic FET cycle than in a fresh cycle.
  相似文献   
59.
Previous studies of episodic memory report a greater extent of blood-oxygenation-level-dependent (BOLD) response in non-demented older adults with the apolipoprotein E epsilon-4 (APOE epsilon4) allele than in those without the allele. We conducted a functional MRI study to investigate whether APOE genotype is related to brain response to verbal paired-associate encoding and consolidation, particularly in the right hemisphere, among non-demented older adults. Structurally segmented volumes and BOLD response were measured in 13 non-epsilon4 and 12 epsilon4 subjects. The epsilon4 group displayed greater activation than the non-epsilon4 group in multiple right hemisphere regions for previously encoded word pairs relative to fixation. Activation within manually outlined hippocampal regions of interest also displayed genotype-specific dissociations consistent with whole brain analyses. Furthermore, this differential BOLD response occurred in the presence of equivalent behavioral and neuropsychological performances as well as comparable hippocampal and overall structural segmentation volumes between groups. Results implicate a widely distributed and interconnected network of right hemisphere brain regions that may be involved in compensating for APOE epsilon4-related deficiencies associated with verbal episodic memory encoding and consolidation.  相似文献   
60.

Background

Using data from a statewide relationship education (RE) program targeting a diverse adolescent sample, this study examined RE implementation in classroom environments.

Objective

The purpose of this study was to explore (1) whether there is a beneficial RE program effect for change in individual attitudes toward sexual delay, (2) whether individual factors—student gender and sexual activity—predict change in attitudes toward sexual delay for students experiencing the intervention, and (3) whether classmate characteristics influence individual change in attitudes toward sexual delay.

Methods

This study utilized multilevel modeling procedures to examine both individual- and classroom-level predictors of change in attitudes toward sexual delay.

Results

At the individual level, results indicated that females demonstrated more change in attitudes toward sexual delay than males and students who were sexually active demonstrated less change toward sexual delay compared with students who were not sexually active. At the classroom level, both racial composition and the proportion of sexually active classmates influenced individual attitude change. Although students in classrooms with higher proportions of African American peers demonstrated less attitude change toward sexual delay, the proportion of sexually active peers in the classroom appeared to be a more salient aspect of classmate composition.

Conclusions

Overall, this study supports the importance of considering both individual characteristics as well as social context when assessing program experience and effectiveness. Implications for future research and practice are offered.
  相似文献   
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