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991.
Culture and environment as predictors of alcohol abuse/dependence symptoms in American Indian youths
This study utilizes Bronfenbrenner's ecological model (1979) to examine multiple and interactive environmental (familial, social, and cultural) predictors of adolescent alcohol abuse/dependence symptoms. A stratified random sample of 401 American Indian youths was interviewed in 2001. The findings showed that family members' substance problems, peer misbehaviors, and participation in generic cultural activities positively predicted adolescent alcohol symptoms. Conversely, cultural pride/spirituality predicted fewer alcohol symptoms, and, importantly, religious affiliation moderated the effects of problematic peers and family members on adolescent alcohol symptoms. The findings suggest further study of intervention and prevention efforts regarding the benefits from consideration of the complex relationships among multiple environmental variables. 相似文献
992.
Greenberg DL Rubin DC 《Cortex; a journal devoted to the study of the nervous system and behavior》2003,39(4-5):687-728
This special issue of Cortex focuses on the relative contribution of different neural networks to memory and the interaction of ‘core' memory processes with other cognitive processes. In this article, we examine both. Specifically, we identify cognitive processes other than encoding and retrieval that are thought to be involved in memory; we then examine the consequences of damage to brain regions that support these processes. This approach forces a consideration of the roles of brain regions outside of the frontal, medial- temporal, and diencephalic regions that form a central part of neurobiological theories of memory. Certain kinds of damage to visual cortex or lateral temporal cortex produced impairments of visual imagery or semantic memory; these patterns of impairment are associated with a unique pattern of amnesia that was distinctly different from the pattern associated with medial-temporal trauma. On the other hand, damage to language regions, auditory cortex, or parietal cortex produced impairments of language, auditory imagery, or spatial imagery; however, these impairments were not associated with amnesia. Therefore, a full model of autobiographical memory must consider cognitive processes that are not generally considered ‘core processes,' as well as the brain regions upon which these processes depend. 相似文献
993.
The hypothalamic-pituitary-adrenal (HPA) axis has differential physiological activity in male and female animals (sexual diergism). Central cholinergic systems stimulate this endocrine axis. In the present study we investigated muscarinic and nicotinic cholinergic influences on HPA axis activity in male and female rats by pretreatment with selective cholinergic receptor antagonists followed by stimulation with physostigmine (PHYSO), an acetylcholinesterase inhibitor. Hormonal measures were plasma arginine vasopressin (AVP), adrenocorticotropic hormone (ACTH), and corticosterone (CORT). Male rats had significantly greater AVP and ACTH responses to PHYSO alone than did females. Scopolamine (SCOP) enhanced the AVP response to PHYSO to a greater extent in males than in females. In contrast, mecamylamine (MEC) enhanced the AVP response in females but decreased it in males. SCOP potentiated, and MEC inhibited, the stimulatory effect of PHYSO on ACTH in both sexes, but SCOP potentiation was greater in males, and MEC inhibition was greater in females. Absolute CORT increases following PHYSO were greater in females, but percent increases over baseline were greater in males. Similar to their effects on ACTH responses, MEC attenuated, and SCOP enhanced, CORT responses to PHYSO. These results suggest that cholinergic receptor subtypes may influence HPA axis activity differentially in male and female rats. 相似文献
994.
Lihi?Atzmony Ofer?Reiter Emmilia?Hodak Michael?Gdalevich Daniel?MimouniEmail author 《American journal of clinical dermatology》2016,17(1):11-22
Background
Cutaneous lichen planus (CLP) is an inflammatory dermatosis. Its chronic relapsing course and frequently spontaneous regression hamper the assessment of treatment effectiveness.Objective
To evaluate the efficacy of available treatment modalities for CLP.Data Sources
PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov registry.Methods
We performed a systematic review of the current literature. All randomized controlled trials, nonrandomized case–control studies, and cohort studies with more than one treatment arm were included. The primary outcomes were complete response and time to complete response. The secondary outcomes were partial response, relapse, time to relapse, reduction of itch, the adverse event rate, and withdrawal due to adverse events.Data Synthesis
Sixteen studies met the inclusion criteria, of which 11 were randomized controlled trials. Most trials had a small sample size. In the rare studies in which variants other than generalized or classic lichen planus were included, they could not be analyzed separately. Body-of-evidence quality ranged from very low to moderate. Acitretin, sulfasalazine, and griseofulvin were associated with increased overall response rates in comparison with placebo. Narrow-band ultraviolet B radiation (NBUVB) was more effective than 6 weeks’ low-dose prednisolone in achieving a complete response, and prednisolone was more effective than enoxaparin. Hydroxychloroquine was more effective than griseofulvin in achieving an overall response. Betamethasone valerate 0.1 % ointment had comparable efficacy to calcipotriol ointment. Methotrexate was effective, with a nonsignificant difference in the complete response rate in comparison with oral betamethasone. In nonrandomized controlled trials, oral psoralen plus ultraviolet A photochemotherapy (PUVA) had comparable efficacy to a PUVA bath and NBUVB. Psoralen plus sunlight exposure (PUVASOL) and betamethasone dipropionate 0.05 % cream were effective relative to a short course of oral metronidazole.Conclusions
Several effective treatment options are available for CLP. Further well-designed studies are warranted to investigate the efficacy of topical glucocorticoids—the current first-line therapy—as well as other treatment modalities, and the treatment of different variants of CLP.995.
Kim K Johnson LA Jia C Joyce JC Rangwalla S Higgins PD Rubin JM 《Ultrasound in medicine & biology》2008,34(6):902-912
Inflammation occurs in episodic flares in Crohn's disease, which are part of the waxing and waning course of the disease. Healing between flares allows the intestine to reconstitute its epithelium, but this healing results in the deposition of fibrotic scar tissue as part of the healing process. Repeated cycles of flares and healing often lead to clinically significant fibrosis and stenosis of the intestine. Patients are treated empirically with steroids, with their many side effects, in the hope that they will respond. Many patients would be better treated with surgery if we could identify which patients truly have intestinal fibrosis. Ultrasound elasticity imaging (UEI) offers the potential to radically improve the diagnosis and management of local tissue elastic property, particularly intestinal fibrosis. This method allows complete characterization of local intestine tissue with high spatial resolution. The feasibility of UEI on Crohn's disease is demonstrated by directly applying this technique to an animal model of inflammatory bowel disease (IBD). Five female Lewis rats (150-180g) were prepared with phosphate buffered solution (PBS) as a control group and six were prepared with repeated intrarectal administration of trinitrobenzenesulfonic acid (TNBS) as a disease group. Preliminary strain measurements differentiate the diseased colons from the normal colons (p < 0.0002) and compared well with direct mechanical measurements and histology (p < 0.0005). UEI provides a simple and accurate assessment of local severity of fibrosis. The preliminary results on an animal model also suggest the feasibility of translating this imaging technique directly to human subjects for both diagnosis and monitoring. 相似文献
996.
997.
Objectives: To quantify the differences in gait variability and balance performance between typically developed (TD) children and children with post-traumatic brain injury (TBI) and to determine the association between gait variability and functional balance in both groups.
Design: Cross-sectional study.
Setting: Physical therapy department of a paediatric and adolescent rehabilitation hospital.
Participants: A convenience sample of 24 children post-TBI and 24 TD age and sex matched controls.
Intervention: Not applicable.
Main outcome measure: Step length, step time and base width variability measured with an electronic walkway; timed up and go (TUG) test and functional reach test (FRT) as a functional balance test.
Results: Base width and step time variability showed no significant difference between the groups. However, children post-TBI had significantly greater variability in step length in comparison to healthy controls. The functional balance abilities of children post-TBI were significantly limited compared to TD children. A significant linear inverse correlation was found between balance performance and step length variability only among children with a TBI.
Conclusion: Ambulatory children post-severe TBI had decreased balance performance, decreased gait speed and increased step length variability as compared to age-matched healthy controls. 相似文献
Design: Cross-sectional study.
Setting: Physical therapy department of a paediatric and adolescent rehabilitation hospital.
Participants: A convenience sample of 24 children post-TBI and 24 TD age and sex matched controls.
Intervention: Not applicable.
Main outcome measure: Step length, step time and base width variability measured with an electronic walkway; timed up and go (TUG) test and functional reach test (FRT) as a functional balance test.
Results: Base width and step time variability showed no significant difference between the groups. However, children post-TBI had significantly greater variability in step length in comparison to healthy controls. The functional balance abilities of children post-TBI were significantly limited compared to TD children. A significant linear inverse correlation was found between balance performance and step length variability only among children with a TBI.
Conclusion: Ambulatory children post-severe TBI had decreased balance performance, decreased gait speed and increased step length variability as compared to age-matched healthy controls. 相似文献
998.
BACKGROUND: Failure of cancer immunotherapy is essentially due to immunological tolerance to tumor-associated antigens (TAAs), as these antigens are also expressed in healthy tissues. METHODS: Here, we used transgenic adenocarcinoma of mouse prostate (TRAMP) mice, which develop lethal prostate cancer due to prostate-specific expression of SV40 T antigen (Tag), to evaluate effects of prostatic transformation on oncogene TAA-specific tolerance and to test the possibility of breaking such tolerance using a modified recombinant vaccinia virus. RESULTS: We showed that Tag expression in TRAMP mice is uniquely extra-thymic, and levels of prostatic Tag expression positively correlate with malignant transformation of the prostate. Yet, young tumor-free TRAMP mice were tolerant to Tag antigen. We therefore attempted overcoming such peripheral oncogene-specific T cell tolerance through immunization with a vaccinia construct encoding Tag immunogenic epitopes. This vaccination modality showed that oncogene-specific tolerance was successfully overcome by effective in vivo priming of Tag-specific cytotoxic T cells (CTLs). However, this was restricted to young TRAMP mice. Tag-specific CTL from "tumor na?ve" young TRAMP mice showed significant anti-tumor efficacy in vivo by eliminating established heterotopic prostate tumors and prolonging survival in SCID mice harboring Tag-expressing tumors. In contrast, older TRAMP mice with established prostate tumors exhibited oncogene-specific tolerance as evidenced by failure to generate Tag-specific CTL following Tag-specific immunization. CONCLUSIONS: Peripheral tolerance can be overcome for effective anti-tumor therapy following oncogene-specific immunization. However, this ability to elicit oncogene-specific CTL is impeded in the tumor-bearing host, in the context of increased oncogene expression associated with tumor progression. 相似文献
999.
A 62-year-old woman was admitted with a diagnosis of a distal ureteral stone 2 years after antegrade imaging of the kidney. Ureteroscopy revealed a guidewire tip that transected during the antegrade study. The events leading to guidewire transection were reproduced, and a minor modification of current guidewires is suggested to prevent similar incidents. 相似文献
1000.
NKF-K/DOQI Clinical Practice Guidelines for Vascular Access, Guideline 6, Treatment of Arteriovenous Graft Complications, limit the number of potential indications for stent deployment that may extend the life of the dialysis access (1). The guidelines include recommendations for the treatment of dialysis access stenosis, central vein stenosis, pseudoaneurysms and for angioplasty-associated vascular rupture that cannot be successfully treated by PTA. However, stenting may need to be considered in certain settings falling outside these guidelines. 相似文献