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Over-expression of folate receptor alpha on cancer cells has been frequently exploited for delivery of folate-targeted imaging and therapeutic agents to tumors. Because limited information exists on expression of the beta isoform of the folate receptor in human cancers (FR-β), we have evaluated the immunohistochemical staining pattern of FR-β in 992 tumor sections from 20 different human cancer types using a new anti-human FR-β monoclonal antibody. FR-β expression was shown to be more pronounced in cells within the stroma, primarily macrophages and macrophage-like cells than cancer cells in every cancer type studied. Moreover, FR-β expression in both cancer and stromal cells was found to be statistically more prominent in females than males. A significant positive correlation was also observed between FR-β expression on stromal cells and both the stage of the cancer and the presence of lymph node metastases. Based on these data we conclude FR-β may constitute a good target for specific delivery of therapeutic agents to activated macrophages and that accumulation of FR-β positive macrophages in the stroma could serve as a useful indicator of a tumor''s metastatic potential.  相似文献   
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The insulin‐like growth factors (IGFs), IGF‐1 and IGF‐2, have been implicated in the growth, survival and metastasis of a broad range of malignancies including pediatric tumors. They bind to the IGF receptor type 1 (IGF‐1R) and the insulin receptor (IR) which are overexpressed in many types of solid malignancies. Activation of the IR by IGF‐2 results in increased survival of tumor cells. We have previously identified a novel human monoclonal antibody, m708.5, which binds with high (pM) affinity to both human IGF‐1 and IGF‐2, and potently inhibits phosphorylation of the IGF‐1R and the IR in tumor cells. m708.5 exhibited strong antitumor activity as a single agent against most cell lines derived from neuroblastoma, Ewing family of tumor, rhabdomyosarcoma and osteosarcoma. When tested in neuroblastoma cell lines, it showed strong synergy with temsirolimus and synergy with chemotherapeutic agents in vitro. In xenograft models, the combination of m708.5 and temsirolimus significantly inhibited neuroblastoma growth and prolonged mouse survival. Taken together, these results support the clinical development of m708.5 for pediatric solid tumors with potential for synergy with chemotherapy and mTOR inhibitors.  相似文献   
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The concentration of glycine (Gly) was measured in gray matter (GM) and white matter (WM) in the human brain using single‐voxel localized 1H MRS at 7 T. A point‐resolved spectroscopy sequence with echo time = 150 ms was used for measuring Gly levels in various regions of the frontal and occipital lobes in 11 healthy volunteers and one subject with a glioblastoma. The point‐resolved spectroscopy spectra were analyzed with LCModel using basis functions generated from density matrix simulations that included the effects of volume localized radio‐frequency and gradient pulses. The fraction of GM and white matter within the voxels was obtained from T1‐weighted image segmentation. The metabolite concentrations within the voxels, estimated with respect to the GM + WM water concentrations, were fitted to a linear function of fractional GM content. The Gly concentrations in pure GM and white matter were estimated to be 1.1 and 0.1 mM, with 95% confidence intervals 1.0–1.2 and 0.0–0.2, respectively. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Interactions between cell surface receptors are important regulatory elements in the complex host responses to infections. In this study, it is shown that a classic chemotactic factor, the bacterial chemotactic peptide N-formyl-methionyl-leucylphenyl-alanine (fMLF), rapidly induced a protein-kinase-C-mediated serine phosphorylation and down-regulation of the chemokine receptor CCR5, which serves as a major human immunodeficiency virus (HIV)-1 coreceptor. The fMLF binding to its receptor, formyl peptide receptor (FPR), resulted in significant attenuation of cell responses to CCR5 ligands and in inhibition of HIV-1-envelope-glycoprotein-mediated fusion and infection of cells expressing CD4, CCR5, and FPR. The finding that the expression and function of CCR5 can be regulated by peptides that use an unrelated receptor may provide a novel approach to the design of anti-inflamatory and antiretroviral agents. (Blood. 2000;96:2887-2894)  相似文献   
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138 patients with chronic papillooditis were investigated, 15 of them in a stage of decompensation. In 83.3% of the cases, the diagnosis was not clinically determined (including 68 of 92 endoscoped before their hospitalization--82.9%). 34 patients were diagnosed as having chronic gastroduodenitis, 15--ulcer, 42--chronic cholecystitis, 11--chronic pancreatitis, 4--cholangitis, 9--postcholecystectomic status. All these diseases developed simultaneously with the papillitis. In a second endoscopic check-up with an examination of papilla Vateri, the patients were in all the cases diagnosed without difficulties and the diagnose was confirmed by biopsy. In 21 patients there was confirmed primary papillooditis and in 127--accompanying disorders: chr. gastroduodenitis--29, chr. atrophic gastritis--18, ulcer--15, chr. cholecystitis--42, postcholecystectomic status--9, choledocholithiasis--14, chr. pancreatitis--11. Most often misdiagnosis occurs if: 1) during the routine endoscopic investigation the endoscopist does not examine papilla of Vater; 2) chr. papillitis exists simultaneously with one of the already mentioned diseases that are easier of approach for diagnostics and explanation of the disorders; 3) the clinical picture of papillitis cannot be differentiated from the one of the basic or accompanying disease; 4) the bile drainage is not prevented; 5) the result of the venous biligraphy does not lead to the diagnosis and ERCP is carried out only in a case of a clinical suspicion.  相似文献   
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Objective: To determine whether prolonging the duration of tamoxifen administration beyond the cessation of a combined chemotherapy regimen benefits patients with primary breast cancer with positive findings in axillary nodes who benefit initially from the combined regimen. Design: Nonrandomized, nonconcurrent cohort study. Setting: National Surgical Adjuvant Breast and Bowel Project, conducted in 68 institutions in North America. Patients: Women were included if they had breast cancer with positive nodes and were aged 49 years or less with both estrogen and progesterone receptor levels of 10 fmol or more, aged 50 to 59 years with progesterone receptor levels of 10 fmol or more, or aged 60 to 69 years. Two cohorts were compared: patients who were randomly assigned to the tamoxifen arm of the adjuvant chemotherapy trial (randomized patients) and women who were added to this arm after randomization had ceased (registered patients). Three hundred seventy-seven women in each group who were disease free at the end of the initial 2-year treatment period were followed for an additional 3 years. Interventions: All received melphalan, fluorouracil, and tamoxifen (10 mg twice daily by mouth) for 2 years. Registered patients (but not randomized patients) were offered tamoxifen for a third year after the initial 2-year treatment period, and 273 (72%) agreed. Measurements and Main Results: Women receiving a third year of tamoxifen had a better disease-free survival rate (odds ratio, 1.54; 95% confidence interval, 1.14 to 2.07; p = 0.004) and survival rate (odds ratio, 1.56; 95% Cl, 1.02 to 2.37; p = 0.04) through their fifth postoperative year. Women aged 50 years or more benefited, but those aged 49 years or less did not. Conclusions: The benefit of tamoxifen given to tamoxifen-responsive patients in conjunction with melphalan and fluorouracil appears to be enhanced when the tamoxifen treatment is continued beyond cessation of treatment with these agents.  相似文献   
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