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21.
CD80 and CD86 were detected in high amounts on circulating T cells in the peripheral blood of some patients with systemic lupus erythematosus (SLE), using flow cytometry and monoclonal antibodies. Patients with other connective tissue diseases did not have a high percentage of T cells expressing CD80 or CD86 in their peripheral blood. CD80 was expressed mainly on CD4 T cells, whereas CD86 was expressed on CD8 T cells, and these two populations were associated with paticular clinical features. These two molecules were expressed on different T-cell populations and might have different roles in the generation and regulation of immune responses. Since high expression of CD86 on T cells was detected much earlier than the appearance of clinical features and a high titer of anti-DNA antibody, it may be a useful parameter for predicting the flare of SLE.  相似文献   
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23.
Cellular mortal and immortal phenotypes as defined by the limited and the infinite capacity of cells to divide are the characteristics of normal and cancerous cells in culture. Numerous strategies that have been employed to understand the mechanism(s) of normal as well as tumor cell growth have revealed that these are genetically controlled, however, the genes and the synchronized regulations remain largely undefined so far. The present report reviews the identification of mortalin, a novel member of murine hsp70 family of proteins, as a gene involved in pathways that determine divisional phenotype of cells in vitro. In the present study, the anti-proliferative activity of mortalin is demonstrated also in human skin fibroblasts (TIG-73PD) by microinjection of anti-mortalin antibody. Furthermore, studies on the mortalin immunofluorescence patterns in SV40-immortalized pre-crisis and post-crisis human cells have revealed that the change in the intracellular distribution of mortalin is linked to the change in the divisional phenotype of cells. Thus, the studies to resolve the molecular basis of association of the cytosolically distributed form of mortalin with cellular mortal phenotype would be important in understanding of the mechanism(s) that determine replicative potential of cells in culture.  相似文献   
24.
In an earlier study in Indonesia we reported on adverse reactions to diethylcarbamazine (DEC) in brugian filariasis patients identified as microfilaraemics (n = 26), endemic normals (n = 11) and elephantiasis patients (n = 17). To assess the link between adverse reactions and cytokines we have now analysed an array of inflammatory mediators in plasma samples collected during the same study. Pre-treatment levels of interleukin (IL)-6 and soluble tumour necrosis factor receptor 75 (sTNF-R75) were higher in elephantiasis patients compared to microfilaraemics and endemic normals, indicating the presence of an ongoing inflammation in patients with chronic disease. After initiation of treatment, the levels of IL-6 and LPS-binding protein (LBP) were consistently and significantly higher in microfilaraemics who suffered most from adverse reactions compared with endemic normals and elephantiasis patients. In microfilaraemics the levels of sTNF-R75 increased after treatment to reach levels recorded in elephantiasis patients. IL-6 increased early, concurrent with the development of adverse reactions and peaked by 24 h post treatment. The levels of LBP and sTNF-R75 in microfilaraemics also increased to peak, later than IL-6, at 32 h post DEC therapy. Although changes were recorded in IL-8 and IL-10 levels in some individuals, no significant differences were found between the 3 clinical groups. These results demonstrate that intake of DEC leads to an increase in a selected number of inflammatory mediators in the group of filarial patients who suffer most from adverse systemic reactions.  相似文献   
25.
Serine proteases are considered to play several important roles in the brain. In an attempt to find novel brain-specific serine proteases (BSSPs), motopsin (PRSS-12) was cloned from a mouse brain cDNA library by polymerase chain reaction (PCR). Northern blot analysis demonstrated that the postnatal 10-day mouse brain contained the most amount of motopsin mRNA. At this developmental stage, in situ hybridization histochemistry showed that motopsin mRNA was specifically expressed in the following regions: cerebral cortical layers II/III, V and VIb, endopiriform cortex and the limbic system, particularly in the CA1 region of the hippocampal formation. In addition, in the brainstem, the oculomotor nucleus, trochlear nucleus, mecencephalic and motor nuclei of trigeminal nerve (N), abducens nucleus, facial nucleus, nucleus of the raphe pontis, dorsoral motor nucleus of vagal N, hypoglossal nucleus and ambiguus nucleus showed motopsin mRNA expression. Expression was also found in the anterior horn of the spinal cord. The above findings strongly suggest that neurons in almost all motor nuclei, particularly in the brainstem and spinal cord, express motopsin mRNA, and that motopsin seems to have a close relation to the functional role of efferent neurons.  相似文献   
26.
Huntington disease (HD) is an autosomal dominant neurodegenerative disorder. To investigate the mechanism of neurodegeneration induced by mutant huntingtin, we developed a stable neuro2a cell line expressing truncated N-terminal huntingtin (tNhtt) with EGFP using the ecdysone-inducible system. The formation of aggregates and the cell death induced by expression of tNhtt with expanded polyglutamine was repeat length- and dose-dependent. Caspases were activated, and the death substrates of caspases, lamin B and ICAD (an inhibitor of caspase-activated DNase), were cleaved in this cell death process. The cleavage of lamin B was inhibited by caspase inhibitors. These findings suggest that the cell death induced by tNhtt with expanded polyglutamine is mediated by caspases.  相似文献   
27.
Cultured rabbit gastric epithelial cells producing prostaglandin I2   总被引:3,自引:0,他引:3  
A new method with Dispase, a bacterial neutral protease, was developed for purification of gastric mucosal cells from rabbit fetuses. These cells formed a typical polygonal monolayer after removal of fibroblastlike cells by Dispase treatment, and preserved the features of "normal" cells, exhibiting in vitro aging with a finite life span. The culture consisted mainly of surface mucous cells (50%-60% of the total cell population) and produced prostaglandins (predominantly I2). The addition of acetylsalicylic acid to the culture medium caused marked inhibition of prostaglandin production by the cultured gastric epithelial cells. This epithelial cell strain will be useful in studies on cytoprotection of the stomach.  相似文献   
28.
A rare case of intramedullary spinal cord metastasis associated with hemorrhage was reported. A 74-year-old man had a subacute onset of paraparesis. He became almost paraplegic within a few days. MRI revealed an intramedullary spinal lesion in the epiconus at the Th 11 and Th 12 level, but spinal angiography did not show any abnormality. Since repeated MRI showed enlargement of the lesion, surgery was performed under the diagnosis of an intramedullary spinal cord tumor. Under general anesthesia, a midline myelotomy of about 3 cm was performed and a grayish, elastic and circumscribed tumor as well as a liquefied hematoma in the caudal part was observed. Both the tumor and the hematoma were removed almost totally. The patient's paraparesis improved slightly after surgery. The histological diagnosis was adenocarcinoma. The primary source was unknown, but multiple small metastatic tumors were found in the lung, liver and brain, etc. Hemorrhage from intramedullary spinal cord metastasis is extremely rare with only 6 reported cases in the recent literature. Rapid deterioration of symptoms caused by the hematoma may make the diagnosis more difficult. Indication of surgical treatment should be carefully determined because prognosis of intramedullary spinal cord metastasis is generally very poor.  相似文献   
29.
The effect of graft-versus-host disease (GVHD) on relapse incidence and survival has been analyzed in several studies, but previous studies included heterogeneous patients. Therefore, we analyzed the data of 2114 patients who received unmanipulated bone marrow graft from an HLA-identical sibling donor with a GVHD prophylaxis using cyclosporin A and methotrexate. Among the 1843 patients who survived without relapse at 60 days after transplantation, 435 (24%) developed grade II-IV acute GVHD. Among the 1566 patients who survived without relapse at 150 days after transplantation, 705 (47%) developed chronic GVHD. The incidence of relapse was significantly lower in patients who developed acute or chronic GVHD, but disease-free survival (DFS) was significantly inferior in patients who developed acute GVHD. A benefit of 'mild' GVHD was only seen in high-risk patients who developed grade I acute GVHD. The strongest association between GVHD and a decreased incidence of relapse was observed in patients with standard-risk acute myelogenous leukemia/myelodysplastic syndrome. In conclusion, the therapeutic window between decreased relapse and increased transplant-related mortality due to the development of GVHD appeared to be very narrow.  相似文献   
30.
Few studies have examined the association of alcohol consumption and cigarette smoking with colorectal cancer in Asian populations whose genetic susceptibility to these factors are different from Western populations. We investigated this association and the joint effect of these factors, and estimated the population-attributable fraction to clarify the public health impact on a Japanese population, based on a prospective study. We analyzed the 10-year (cohort I) and 7-year (cohort II) follow-up data of the Japan Public Health Center-based prospective study on cancer and cardiovascular disease, derived from 90,004 (42,540 male and 47,464 female) middle-aged and elderly Japanese. We identified 716 (457 in men and 259 in women) newly diagnosed cases of colorectal cancer. Both alcohol consumption and smoking were clearly associated with colorectal cancer in men, after adjusting for age, family history of colorectal cancer, body mass index, and physical exercise. Regular heavy drinking of 150 g/week or more of ethanol showed a statistically significant increased risk compared with nondrinkers: relative risks (RRs) were 1.4 [95% confidence interval (CI), 1.1-1.9] for 150-299 g/week and 2.1 (95% CI, 1.6-2.7) for 300 g/week or more. On the contrary, regular ethanol consumption was not associated with colorectal cancer (RR, 0.7; 95% CI, 0.4-1.1) in women. In terms of smoking, the RRs were 1.4 (95% CI, 1.1-1.8) for current smokers and 1.3 (95% CI, 0.98-1.7) for ex-smokers compared with never-smokers in men. The risk of smoking in women was similar to that in men, although not statistically significant. The colorectal cancer risk with 300 g/week or more of ethanol in current smokers was estimated at 3.0 (95% CI, 1.8-5.1) compared with nondrinkers among nonsmokers in men. Colorectal cancer attributable to alcohol consumption or smoking was estimated to be 46%. In conclusion, approximately half of the colorectal cancer cases may be preventable by tobacco and alcohol controls in middle-aged and elderly Japanese men.  相似文献   
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