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BACKGROUND: Hispanics now represent a majority of residents in Miami-Dade County, Florida. In this report, the authors present new cancer incidence and mortality data for South Florida's Hispanic men for the period 1990-1998 and compare them with data from a previous report from the 1980s. Periodic updating of cancer incidence data, reflecting current population distribution, lifestyle, and environmental risk factors, is necessary to inform cancer prevention and control activities optimally. METHODS: The study population consisted of all incidents of cancer (1981-1998) occurring in males from Miami-Dade County, as determined from the Florida Cancer Data System data base; patients were divided into two 9-year periods for analysis. Age-standardized incidence and mortality rates were computed for 14 common cancer sites, and rates for Hispanic men were compared with the rates for non-Hispanic white men as standardized rate ratios (SRRs) with 95% confidence intervals (95% CIs). Incidence and mortality trends were determined using linear regression analysis. RESULTS: Nearly 70,000 incident cancer cases were analyzed. For 1990-1998, the top five incident cancers for both race/ethnic groups were the same. The overall decreased cancer risk for Hispanic men (SRR, 0.80; 95% CI, 0.79-0.82), compared with non-Hispanic white men, remained essentially constant over the two study periods. Cancer incidence increased similarly for the two race-ethnic groups; cancer mortality decreased, with a sharper decrease for non-Hispanic white men, resulting in apparent convergence of mortality trends recently. CONCLUSIONS: Differences in cancer risk for South Florida's Hispanic men have not attenuated over the past 20 years. With cancer incidence significantly less for Hispanic men, their mortality rate approaches that of non-Hispanic white men, and cancer prevention and control strategies targeted for this ethnic group become increasingly important.  相似文献   
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Orthotopic brain tumor growth is inhibited in athymic mice by the daily systemic administration of the alpha v-integrin antagonist EMD 121974. This compound, a cyclic RGD-penta-peptide, is a potent inhibitor of angiogenesis, which induces apoptosis of growing endothelial cells through inhibition of their alpha v-integrin interaction with the matrix proteins vitronectin and tenascin. Here we show that EMD 121974 also induces apoptosis in the alpha v-integrin-expressing tumor cell lines U87 MG and DAOY by detaching them from vitronectin and tenascin, matrix proteins known to be essential for brain tumor growth and invasion. These matrix proteins are shown to be produced by the brain tumor cells in vitro and in vivo. Furthermore, only tumor cells expressing alpha v-integrins responded to the treatment with EMD 121974, after xenotransplantation into the forebrain of nude mice, supporting the importance of tumor cell-matrix interactions in tumor cell survival in the brain. Thus, the alpha v-antagonist EMD 121974 suppresses brain tumor growth through induction of apoptosis in both brain capillary and brain tumor cells by preventing their interaction with the matrix proteins vitronectin and tenascin. The dual action of this peptide explains its potent growth suppression of orthotopically transplanted brain tumors.  相似文献   
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BACKGROUND: The Hispanic population now represents the majority of residents in Miami-Dade County, Florida. The authors present cancer incidence and mortality data for South Florida's Hispanic women for the period 1990-1998 and compare these data to previously reported data from 1981-1989. Cancer incidence, risk, and mortality data should reflect current population distribution, lifestyle, and environmental risk factors so that cancer prevention and control activities are informed optimally. METHODS: The study population consisted of all women with malignant disease during 1981-1998 from Miami-Dade County found in the Florida Cancer Data System data base; patients were divided into 2 9-year periods for analysis. Age-standardized incidence and mortality rates were computed for common disease sites; rates for Hispanic women were compared with the rates for non-Hispanic white (NHW) women as standardized rate ratios (SRR) with 95% confidence intervals (95%CIs). Incidence and mortality trends were analyzed using linear regression. RESULTS: Over 70,000 cancer incidents were analyzed. The overall decreased cancer risk for Hispanic women (SRR, 0.65; 95%CI, 0.64-0.67), compared with NHW women, remained essentially constant over the two study periods. Cancer incidence increased similarly for the two racial-ethnic groups. The incidence of lung carcinoma increased in both groups, becoming the second most common disease site for NHW women and the third most common disease site for Hispanic women. CONCLUSIONS: The decreased relative cancer risk for Hispanic women in South Florida has remained stable over the past 18 years. Lung carcinoma is increasing among women in both racial-ethnic groups.  相似文献   
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Biologically and clinically meaningful tumor classification schemes have long been sought. Some malignant epithelial neoplasms, such as those in the thyroid and endometrium, exhibit more than one pattern of differentiation, each associated with distinctive clinical features and treatments. In other tissues, all carcinomas, regardless of morphological type, are treated as though they represent a single disease. To better understand the biological and clinical features seen in the four major histological types of ovarian carcinoma (OvCa), we analyzed gene expression in 113 ovarian epithelial tumors using oligonucleotide microarrays. Global views of the variation in gene expression were obtained using PCA. These analyses show that mucinous and clear cell OvCas can be readily distinguished from serous OvCas based on their gene expression profiles, regardless of tumor stage and grade. In contrast, endometrioid adenocarcinomas show significant overlap with other histological types. Although high-stage/grade tumors are generally separable from low-stage/grade tumors, clear cell OvCa has a molecular signature that distinguishes it from other poor-prognosis OvCas. Indeed, 73 genes, expressed 2- to 29-fold higher in clear cell OvCas compared with each of the other OvCa types, were identified. Collectively, the data indicate that gene expression patterns in ovarian adenocarcinomas reflect both morphological features and biological behavior. Moreover, these studies provide a foundation for the development of new type-specific diagnostic strategies and treatments for ovarian cancer.  相似文献   
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Polyphosphazene based microspheres for insulin delivery were prepared following three different procedures: (A) suspension-solvent evaporation; (B) double emulsion-solvent evaporation; (C) suspension/double emulsion-solvent evaporation. Methods A and C allowed for higher protein loading than procedure B. Scanning electron microscopy showed that all preparation procedures achieve microparticles with spherical shape, porous surface and internal honeycomb structure. In all cases insulin was released 'in vitro' by a bi-modal behaviour: fast release during the first 2 hours followed by a slow release. However, both the physical properties and the 'in vitro' release profiles were found to depend upon the preparation conditions. Subcutaneous administration to diabetic mice of microspheres obtained with methods A and C rapidly reduced the glucose levels of about 80% but most of activity was lost in 100 hours. Both preparations B induced a remarkable decrease in glucose levels and the activity was maintained throughout 1000 h. Finally all preparations stimulated anti-insulin antibody production that constantly increased over a period of 8 weeks.  相似文献   
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Hydrogels prepared by radiation-induced polymerization at a low temperature have been used as carriers for the controlled release of peptides and proteins. It was found that polymerization of 2-hydroxyethyl methacrylate in the presence of poly (ethylene glycol) methyl ether (MPEG) enabled the more porous and swellable matrics to be obtained, the higher the molecular weight of MPEG. As a consequence, protein release took place at an increasing extent and, provided that MPEG molecular weight was high enough, high molecular weight proteins could also be released. Such a state of affairs was not met in the case of hydrogels based on poly (2-hydroxyethyl acrylate). SEM analysis revealed that even high molecular weight MPEG did not give rise to any porosity, even though the degree of swelling was very high. As a result, no protein release was observed. It was therefore concluded that control of hydrogel porosity for the controlled release of large proteins is of overwhelming importance.  相似文献   
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