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991.
992.
A genome-independent microarray and new statistical techniques were used to genotype Bacillus strains and quantitatively compare DNA fingerprints with the known taxonomy of the genus. A synthetic DNA standard was used to understand process level variability and lead to recommended standard operating procedures for microbial forensics and clinical diagnostics.  相似文献   
993.
Caspofungin has recently been introduced for the treatment of invasive candidiasis, however, there is limited data on its use in endocarditis. We report a 22-year-old male HIV-infected patient on methadone maintenance therapy that developed right-sided Candida albicans endocarditis. Caspofungin treatment and vegetectomy, followed by fluconazole, was successful in the treatment of our patient. We also review all previous cases of Candida endocarditis treated with caspofungin.  相似文献   
994.
A case of a 45-day-old male infant, bitten on the neck by nose-horned viper (Vipera ammodytes ammodytes), is reported. This episode occurred while the baby was on a picnic with his parents in a hill near a town in southern Croatia. In spite of immediate arrival at hospital, where antivenom was administrated and all the necessary treatment measures were carried out, the infant died 6 h following the bite. The cause of death was severe and progressive hyperkalaemia, massive intravascular haemolysis, severe coagulopathy and myocardial dysfunction.  相似文献   
995.
996.
In endoscopic biopsies, desmoplastic stroma and/or tumor invasion of the submucosa are generally regarded as histologic features that allow for the diagnosis of colorectal carcinoma (CRC). They are not present in all endoscopic biopsies of CRC. We investigated tumor necrosis and invasion of adjacent normal mucosa for their usefulness as possible additional histologic criteria for CRC, and evaluated quantitatively the diagnostic reliability of each of the four aforementioned histologic features in routine biopsy practice. We analyzed 440 endoscopic biopsies of lesions endoscopically suspicious of CRC and compared them with 26 colorectal adenomas with malignant change and 344 colorectal adenomas. The slides were stained by H&E and the Kreyberg-Jareg trichrome method. The endoscopic histologic diagnoses were verified by histologic examination of surgically resected specimens. In endoscopic biopsies of CRC, desmoplastic stroma was found in 83.6% of the cases, tumor necrosis in 75.7%, submucosal invasion in 27.0%, and invasion of normal mucosa in 22.7%. When only one of the diagnostic features was present, there was a false positivity of 2.5-13.3%; however, the latter has fallen to 0.8% when two features were present, but disappeared when there were three or four histologic features. Adenomas with malignant change showed necrosis in 69.2% and invasion of adjacent mucosa in 15.3%. In adenomas, necrosis was present in 0.6% of the cases, desmoplastic stroma in 3.2%, and shallow erosions in 27.3%. The presence of tumor necrosis and invasion of normal mucosa were characteristic histologic features of CRC; therefore, they represent useful additional histologic criteria for the diagnosis of CRC in endoscopic biopsies. The reliability of the histologic diagnosis of CRC correlated with the number of the four aforementioned histologic features.  相似文献   
997.
Mesalamine (5-ASA) is widely used for the treatment of ulcerative colitis, a remitting condition characterized by chronic inflammation of the colon. Knowledge about the molecular and cellular targets of 5-ASA is limited and a clear understanding of its activity in intestinal homeostasis and interference with neoplastic progression is lacking. We sought to identify molecular pathways interfered by 5-ASA, using CRC cell lines with different genetic background. Microarray was performed for gene expression profile of 5-ASA-treated and untreated cells (HCT116 and HT29). Filtering and analysis of data identified three oncogenic pathways interfered by 5-ASA: MAPK/ERK pathway, cell adhesion and β-catenin/Wnt signaling. PAK1 emerged as a consensus target of 5-ASA, orchestrating these pathways. We further investigated the effect of 5-ASA on cell adhesion. 5-ASA increased cell adhesion which was measured by cell adhesion assay and transcellular-resistance measurement. Moreover, 5-ASA treatment restored membranous expression of adhesion molecules E-cadherin and β-catenin. Role of PAK1 as a mediator of mesalamine activity was validated in vitro and in vivo. Inhibition of PAK1 by RNA interference also increased cell adhesion. PAK1 expression was elevated in APCmin polyps and 5-ASA treatment reduced its expression. Our data demonstrates novel pharmacological mechanism of mesalamine in modulation of cell adhesion and role of PAK1 in APCmin polyposis. We propose that inhibition of PAK1 expression by 5-ASA can impede with neoplastic progression in colorectal carcinogenesis. The mechanism of PAK1 inhibition and induction of membranous translocation of adhesion proteins by 5-ASA might be independent of its known anti-inflammatory action.  相似文献   
998.
Hsp70 chaperone is known to stimulate anti-tumour immunity in a variety of cancer models. Here we demonstrated that the addition of purified recombinant Hsp70 to the culture medium facilitated cancer cell cytolysis by lymphocytes. Importantly, exogenous Hsp70 triggered secretion of the intracellular Hsp70 to a cell surface and extracellular milieu, which played a role in cytolysis because down-regulation of the endogenous Hsp70 reduced both its presence at the cell surface and the lymphocyte-mediated cytolysis. Inhibitors that target both the ATPase and the peptide-binding domains of Hsp70 molecule potently decreased its anti-tumor effect. Using a variety of cell transport markers and inhibitors, we showed that the exchange of exogenous and intracellular Hsp70 is supported by classical and non-classical transport pathways, with a particular role of lipid rafts in the chaperone''s intracellular transport. In conclusion, exogenous Hsp70 can eject endogenous Hsp70, thus exerting anticancer activity.  相似文献   
999.
Rectal cancer: the sphincter-sparing approach   总被引:8,自引:0,他引:8  
There is considerable skepticism regarding sphincter-preserving surgery for rectal cancer, and 40% to 60% APR rates are reported in many prospective studies. Despite radical surgery, 20% positive margin rates are frequently reported. Rectal carcinoma responds to preoperative chemoradiation therapy with a 10% to 15% pathologic complete response rate. Preoperative therapy offers an opportunity to reduce the positive margin rate and to reduce the APR rate. Because there is significant tumor regression with preoperative therapy, distal margins of less 1 cm are acceptable and do not result in suture line recurrence. APR rate of less than 10% is feasible and better chemotherapy with radiation therapy will reduce the APR to less than 5%.  相似文献   
1000.
SMAD4 is a downstream mediator of transforming growth factor beta. While its tumor suppressor function has been investigated as a prognostic biomarker in several human malignancies, its role as a prognostic marker in breast carcinoma is still undefined. We investigated SMAD4 expression in breast carcinoma samples of different histologic grades to evaluate the association between SMAD4 and outcome in breast cancer. We also investigated the role of SMAD4 expression status in MDA-MB-468 breast cancer cells in responding to TGF-β stimulation. SMAD4 expression was assessed in 53 breast ductal carcinoma samples and in the surrounding normal tissue from 50 of the samples using immunohistochemistry, Western blot, and real-time PCR. TGF-β-SMAD and non-SMAD signaling was assessed by Western blot in MDA-MB-468 cells with and without SMAD4 restoration. SMAD4 expression was reduced in ductal breast carcinoma as compared to surrounding uninvolved ductal breast epithelia (p?<?0.05). SMAD4 expression levels decreased from Grade 1 to Grade 3 ductal breast carcinoma as assessed by immunohistochemistry (p?<?0.05). Results were recapitulated by tissue array. In addition, immunohistochemistry results were further confirmed at the protein and mRNA level. We then found that non-SMAD MEK/MAPK signaling was significantly different between SMAD4 expressing MDA-MB-468 cells and SMAD4-null MDA-MB-468 cells. This is the first study indicating that SMAD4 plays a key role in shifting MAPK signaling. Further, we have demonstrated that SMAD4 has a potential role in the development of breast carcinoma and SMAD4 was a potential prognostic marker of breast carcinoma. Our findings further support the role of SMAD4 in breast carcinoma development. In addition, we observed an inverse relationship between SMAD4 levels and breast carcinoma histological grade. Our finding indicated that SMAD4 expression level in breast cancer cells played a role in responding non-SMAD signaling but not the canonic SMAD signaling. Further mechanistic studies are necessary to establish the role of SMAD4 in breast carcinoma prognosis and potential specific targeting.  相似文献   
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