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111.
Zhang JX  Zhuang J  Ma L  Yu W  Peng D  Ding G  Zhang Z  Weng X 《NeuroImage》2004,23(3):975-982
This study utilized fast event-related fMRI with reversible words to examine the role of left inferior prefrontal cortex (PFC) in semantic processing of Chinese. As a special linguistic phenomenon in Chinese, a reversible word is a two-character word (AB) that, when read from right to left (BA), opposite to the normal left to right reading direction, is also a real word. The two words, AB and BA, can have very different meanings. Fourteen native Chinese saw a reversible word (BA) and were asked to read it backward silently to obtain the meaning of AB, defined as the target meaning. They then saw two test words and decided which of the two was semantically related to the target meaning. Activity in a subregion of BA47 was found to be modulated by the extent to which irrelevant semantic activation of the distractor word BA interfered with semantic retrieval of the target word AB. This finding demonstrated the involvement of the left inferior PFC in the control processes of semantic retrieval in Chinese. In addition, comparing conditions using reversible with that using nonreversible words, we found evidence suggesting a semantic/phonological functional subdivision in left inferior PFC, consistent with that in English.  相似文献   
112.
Objective To explore the effects of dexamethasone on nuclear factor-kB (NF-κB) expression in brain tissue after traumatic brain injury (TBI). Methods Forty rats were randomly divided into two groups: dexamethasone treatment and no treatment, and severe brain injury was produced by gas percussion in both groups. At 0, 6, 24, 72 and 120 hours after injury, 5 rats of each group were executed and the histopathological changes in brain tissue in rats were observed by hematoxylin-eosin (HE) stain. The expression of NF-κB in brain tissue of rats was detected by immunohistochemical method. Results NF-κB expression was significantly up-regulated at 6 hours in brain tissue of rats after TBI (P<0.05), reaching the highest level at 24 hours (P<0. 01). It showed a tendency to lower, but was still high at 120 hours after TBI (P<0. 05 or P<0. 01). After treatment with dexamethasone, NF-κB level was lowered at 6, 24 and 72 hours (all P<0. 01). Conclusion NF-κB expression is up-regulated in brain tissue in early period after TBI, and keeps on a high level, thus inducing inflammatory response to produce secondary injury to brain tissue. Dexamethasone shows protective effects by regulating the levels of NF-κB and prevents secondary injury which is caused by the inflammatory cytokines in rat brain tissue after TBI.  相似文献   
113.
操廉  李庆阳  王林风  王鹏 《实用医学杂志》2008,24(23):4006-4008
目的:探讨熊果酸(Ursolic acid, UA)诱导脑胶质瘤U251细胞株凋亡的作用及机制。方法:培养脑胶质瘤细胞株(U251),应用流式细胞仪观察UA对细胞周期的影响;琼脂糖凝胶电泳观察细胞DNA的变化;Western-blot测定COX-2及凋亡相关蛋白Bcl-2、Bax表达。放射免疫分析法测定COX-2催化产物前列腺素E2(prostaglandin E2, PGE2)。结果:流式细胞术及琼脂糖凝胶电泳均显示UA诱导U251细胞凋亡,细胞核DNA 呈梯状降解。同时COX-2蛋白表达及其催化生成产物PGE2浓度下降,凋亡相关蛋白Bcl-2表达减少,而Bax无明显变化。结论:熊果酸能明显诱导U251细胞凋亡,其机制可能与阻滞细胞周期、抑制COX-2表达、减少PGE2生成及下调凋亡抑制蛋白Bcl-2表达有关。  相似文献   
114.
The global tuberculosis crisis urgently demands new, efficacious, orally available drugs with the potential to shorten and simplify the long and complex treatments for drug-sensitive and drug-resistant disease. Clofazimine, a riminophenazine used for many years to treat leprosy, demonstrates efficacy in animal models of tuberculosis via a novel mode of action. However, clofazimine's physicochemical and pharmacokinetic properties contribute to side effects that limit its use; in particular, an extremely long half-life and propensity for tissue accumulation together with clofazimine's dye properties leads to unwelcome skin discoloration. We recently conducted a systematic structure-activity study of more than 500 riminophenazine analogs for anti-Mycobacterium tuberculosis activity. We describe here the characteristics of 12 prioritized compounds in more detail. The new riminophenazine analogs demonstrated enhanced in vitro activity compared to clofazimine against replicating M. tuberculosis H37Rv, as well as panels of drug-sensitive and drug-resistant clinical isolates. The new compounds demonstrate at least equivalent activity compared to clofazimine against intracellular M. tuberculosis and, in addition, most of them were active against nonreplicating M. tuberculosis. Eleven of these more water-soluble riminophenazine analogs possess shorter half-lives than clofazimine when dosed orally to mice, suggesting that they may accumulate less. Most importantly, the nine compounds that progressed to efficacy testing demonstrated inhibition of bacterial growth in the lungs that is superior to the activity of an equivalent dose of clofazimine when administered orally for 20 days in a murine model of acute tuberculosis. The efficacy of these compounds, along with their decreased potential for accumulation and therefore perhaps also for tissue discoloration, warrants further study.  相似文献   
115.
BACKGROUND: Choice of antibiotic therapy for acute exacerbations of chronic bronchitis (AECB) is important because of cost and concerns about development of resistance. METHODS: A retrospective cohort study was conducted in outpatients with chronic obstructive pulmonary disease and documented AECB treated with antibiotics. RESULTS: We compared outcomes and costs of AECB treated with first-line antibiotics having partial coverage against organisms associated with AECB (eg, amoxicillin), first-line antibiotics with full coverage against organisms associated with AECB (eg, sulfamethoxazole-trimethoprim), and newer broad-spectrum antibiotics (eg, azithromycin). There were no significant differences among the three antibiotic groups in failure rate, hospitalization rate, or time until subsequent AECB. Pharmacy costs were significantly less with first-line antibiotics (3.18 dollars +/- 0.64, 3.00 dollars +/- 0.48, and 36.70 dollars +/- 16.29, respectively; P < 0.0001), but there was no significant difference among all three groups with regard to total costs. CONCLUSION: We found no difference in outcome between older traditional antibiotics with adequate coverage against organisms associated with AECB and newer broad-spectrum antibiotics.  相似文献   
116.

Background:

Renal sympathetic nerves are involved in the reflective activation of the sympathetic nervous system in circulatory control. Catheter-based renal denervation (RDN) ameliorated treatment-resistant hypertension safely, but 10%–20% of treated patients are nonresponders to radiofrequency denervation. The purpose of this study was to investigate the safety and efficiency of cryoablation for sympathetic denervation in a swine model and to explore a new way of RDN.

Methods:

Seven swines randomly assigned to two groups: Renal cryoablation (CR) group and control group. The control group underwent renal angiogram only. The CR group underwent renal angiogram plus bilateral renal cryoablation. Renal angiograms via femoral were performed before denervation, after denervation and prior to the sacrifice to access the diameter of renal arterial and the pressure of aorta abdominalis. Euthanasia of the swine was performed on 28-day to access norepinephrine (NE) changes of the renal cortex and the changes of renal nerves.

Results:

Cryoablation did not induce severe complications at any time point. There was no significant change in diameter of renal artery. CR reduced systolic blood pressure (BP) from 145.50 ± 9.95 mmHg at baseline to 119.00 ± 14.09 mmHg. There was a slight but insignificant decrease in diastolic BP. The main nerve changes at 28-day consisted of necrosis with perineurial fibrosis at the site of CR exposure in conjunction with the nerve vacuolation. Compared with the control group, renal tissue NE of CR group decreased by 89.85%.

Conclusions:

Percutaneous catheter-based cryoablation of the renal artery is safe. CR could effectively reduce NE storing in the renal cortex, and the efficiency could be maintained 28-day at least.  相似文献   
117.
Objectives: Post-operative stiffness is common after rotator cuff repair, given the difference in susceptibility and severity, the genetic factors may be involved. Interleukin 6 (IL-6) and Matrix metalloproteinases 3 (MMP-3) were previous found as key cytokines in the pathologies of adhesive capsulitis. The present study aims to investigate whether variants within the IL-6 and MMP-3 gene contributed to post-operative stiffness in a Chinese Han population. Methods: A total of 188 patients diagnosed with rotator cuff tears treated with mini-open surgery were enrolled in this study, among which 87 patients were diagnosed as post-operative stiffness and the remaining 101 patients as controls. All subjects were genotyped for IL-6 and MMP-3 SNPs. Results: The rs1800796 of IL-6 and rs679620 of MMP-3 were found significantly associated with increased susceptibility and severity of post-operative stiffness. Conclusion: The rs1800796 SNP of IL-6 and rs650108 SNP of MMP-3 were associated with increased risk of post-operative stiffness susceptibility and severity. This finding can be used in guiding the rehabilitation procedure after rotator cuff surgery, in another word, those with the genetic susceptibility factors should receive a more radical rehabilitation procedure and those without the susceptibility factors can be more conservative.  相似文献   
118.
Lysyl oxidase like 4 (LOXL4), a member of the secreted copper-dependent amine oxidases that contribute to the assemble and maintenance of the extracellular matrix (ECM), was found to be up-regulated or down-regulated in different cancer types, suggesting its paradoxical roles in cancer. The specific role of LOXL4 in hepatocellular carcinoma (HCC), however, is still yet to be defined. Twenty-eight pairs of HCC specimens were used for LOXL4 mRNA expression analysis. The mRNA expression in HCC cell lines was examined, and HepG2 was selected for LOXL4 small interfering RNA (siRNA) interference to investigate the biological function of LOXL4, LOXL4 immunohistochemical staining was performed using a tissue microarray containing 298 HCC patients. The prognostic and diagnostic value of LOXL4 was evaluated using Cox regression and Kaplan-Meier analysis. LOXL4 mRNA or protein expression was significantly lower in HCC tissues than peritumoral tissues (LOXL4 mRNA expression, P = 0.018; LOXL4 protein expression, P < 0.001). Low LOXL4 expression was associated with lower overall survival (OS) rates and higher cumulative recurrence rates. Multivariate analysis indicated that LOXL4 was an independent prognostic indicator for OS and time to recurrence (TTR). Our results revealed that LOXL4 was down-regulated in HCC and correlated with aggressive tumors and a worse clinical outcome. LOXL4 may be a potential biomarker to identify the HCC patients with a higher risk of recurrence.  相似文献   
119.
Background: SALL4 is a novel oncogene mediating tumorigenesis in multiple carcinomas. However, its actual role and mechanisms participating in the development of colorectal cancer remains unclear. Methods: Immunohistochemical staining and Western blot were conducted to detect the expression of SALL4 and other molecules. siRNA of SALL4 was transfected to silence SALL4 expression in Caco-2 cell line. Flow cytometry was used for cell cycle and apoptosis analysis. Wound healing and transwell assay were used for invasion test. CCK-8 test was employed for cell proliferation and drug sensitivity assessment. Results: By inhibition of SALL4 expression, the proliferation, invasiveness and drug resistance were dramatically reduced while apoptosis rate was up-regulated. Gli1 was found to decrease its expression in SALL4 silencing cells. Moreover, the inhibition on tumorigenesis of Caco-2 by SALL4 silencing was antagonized by Gli1 up-regulation, suggesting Gli1 as a downstream target of SALL4 in cancer development. Conclusion: SALL4 inhibition limited oncogenesis on colorectal cancer by reducing Gli1 expression.  相似文献   
120.
Vancomycin is a preferred antibiotic for treating Clostridium difficile infection (CDI) and has been associated with a rate of recurrence of CDI of as high as 20% in treated patients. Recent studies have suggested that berberine, an alternative medical therapy for gastroenteritis and diarrhea, exhibits several beneficial effects, including induction of anti-inflammatory responses and restoration of the intestinal barrier function. This study investigated the therapeutic effects of berberine on preventing CDI relapse and restoring the gut microbiota in a mouse model. Berberine was administered through gavage to C57BL/6 mice with established CDI-induced intestinal injury and colitis. The disease activity index (DAI), mean relative weight, histopathology scores, and levels of toxins A and B in fecal samples were measured. An Illumina sequencing-based analysis of 16S rRNA genes was used to determine the overall structural change in the microbiota in the mouse ileocecum. Berberine administration significantly promoted the restoration of the intestinal microbiota by inhibiting the expansion of members of the family Enterobacteriaceae and counteracting the side effects of vancomycin treatment. Therapy consisting of vancomycin and berberine combined prevented weight loss, improved the DAI and the histopathology scores, and effectively decreased the mortality rate. Berberine prevented CDIs from relapsing and significantly improved survival in the mouse model of CDI. Our data indicate that a combination of berberine and vancomycin is more effective than vancomycin alone for treating CDI. One of the possible mechanisms by which berberine prevents a CDI relapse is through modulation of the gut microbiota. Although this conclusion was generated in the case of the mouse model, use of the combination of vancomycin and berberine and represent a novel therapeutic approach targeting CDI.  相似文献   
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