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101.
Anticancer Drug Resistance of HeLa Cells Transfected With Rat Glutathione S-transferase pi Gene 总被引:3,自引:0,他引:3
Cao W Zuo J Meng Y Wei Q Shi ZH Ju LM Fang FD 《Biomedical and environmental sciences : BES》2003,16(2):157-162
Objective To establish a cytologic expressing system of rat glutathione S-transferase pi (GST-pi) cDNA for detecting the resistance of HeLa cells to anticancer drugs. Methods The assessment was made with various anticancer drugs (adriamycin, mitomycin, cisplatinum and vincristine) that showed different cytotoxicities in transfectant HeLa cells with pSV-GT containing rat GST-pi cDNA (HeLa/pSV-GT) or control pSV-neo (HeLa/pSV-neo). Expression levels of GST-pi mRNA in HeLa/pSV-GT and HeLa/pSV-neo were measured by in situ hybridization using Digoxin-labelled cDNA probe. Results HeLa/pSV-GT expressed significantly high degree of GST-pi mRNA, whereas both HeLa/pSV-neo and HeLa cells had very low expression. Cytotoxicities of HeLa/pSV-GT and HeLa/pSV-neo with 4 anticancer drugs were measured by MTT assay. Drug concentrations for yielding 50% inhibition (IC50) in HeLa/pSV-GT by adriamycin, mitomycin and cisplatinum were 70.13μg/mL, 10.95μg/mL and 16.52μg/mE respectively. In contrast, IC50 in HeLa/pSV-neo was 10.34μg/mL, 7.48μg/mL and 13.70μg/mE respectively. The cytotoxicities of vincristine on both HeLa/pSV-GT and HeLa/pSV-neo were not significantly different. Conclusions Our findings suggest that HeLa/pSV-GT containing rat GST-pi cDNA is resistant to some anticancer drugs due to overexpression of GST-pi. Also, HeLa/pSV-GT cell line could serve as a useful cytogenetic model for further research. 相似文献
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104.
引流淋巴结树突状细胞对自身肿瘤细胞作用研究 总被引:1,自引:0,他引:1
目的 从胃癌患者引流淋巴结中分离和定向诱导培养扩增树突状细胞 (DC) ,观察其经自身肿瘤细胞抗原冲击后对自身细胞因子诱导的杀伤细胞 (CIK细胞 )杀伤活性的影响。方法 取手术切除肿瘤周围转移引流淋巴结 ,提取单个核细胞 ,将贴壁生长的细胞用细胞因子rhGM CSF、rhIL 4、rhTNF α联合诱导培养DC ,然后用自身肿瘤细胞抗原冲击DC并作用CIK细胞 ,最后检测CIK细胞杀伤三种靶细胞 (自身胃癌细胞、K5 6 2和SGC 790 1细胞 )的活性。结果 胃癌患者转移引流淋巴结中的贴壁细胞 ,经细胞因子联合诱导培养 ,DC含量可达 4 5 %。经自身肿瘤抗原冲击的引流淋巴结DC活化的CIK细胞 ,杀伤自身肿瘤细胞活性达 79 3% ,单纯CIK细胞为 33% ,两者比较差异有显著意义 (P <0 0 1) ;而对K5 6 2和SGC 790 1细胞杀伤活性无明显差异。结论 肿瘤周围转移引流淋巴结贴壁细胞在体外能定向诱导扩增出大量DC :DC经自身肿瘤抗原冲击后能明显提高CIK细胞对自身肿瘤细胞的杀伤活性。此结果为肿瘤DC的免疫治疗应用奠定了理论基础 相似文献
105.
目的 探讨合并伤对颅脑损伤病死率的影响及其急救原则。方法 总结分析我院收治的 4 311例颅脑损伤病例合并伤资料。结果 颅脑损伤 4 311例中合并伤 1372例 ( 31 8% ) ,其中轻型组 13 7% ,中型组 2 7 9% ,重型及特重型组 5 3 9%。各部位合并伤在总体、<2 4h死亡 ( 16 4例 )组、>2 4h死亡 ( 2 2 9例 )组中的发生率依次为 :颌面部 12 2 %、14 6 %、12 6 % ;胸部 9 3%、32 9%、10 9% ;腹部 1 5 %、9 1%、3 4 % ;脊柱骨盆 3%、2 1 9%、4 8% ;四肢 17 3%、2 0 1%、19 2 %。结论 在颅脑损伤患者的院前、院内急救中要加强对胸部、腹部、脊柱骨盆合并伤的合理救治 相似文献
106.
Objective: To observe the behavioral and biochemical effects of a traditional Chinese medicine Huanshao Dan (HSD) on learning and memory
deficits in transient cerebral ischemia model in mice.Methods: Step-through experiments, receptor binding test and choline acetyltransferase (ChAT) activities determination were performed.Results: Mice undertaken transient ischemia commited much more mistakes in step-through experiments and showed relatively higher3 H-MK801 binding in cerebral cortex and hippocampus than in sham operated animals. HSD decoction was most effective in reducing
these mistakes in mice. At the same time, and3 H-MK801 binding of cerebral cortex and hippocampus tissues were also significantly decreased, while ChAT activities in the
same tissues were increased.Conclusion: HSD might antagonize ischemic injury of brain through inhibition of glutamate N-methyl-D-Aspartic acid receptor overactivity.
ΔThis program was supported by National Nature Science Foundation of China (No.39421012) 相似文献
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Karl T. Kelsey Margaret R. Spitz Zheng-Fa Zuo John K. Wiencke 《Cancer causes & control : CCC》1997,8(4):554-559
The genes coding for separate isoforms of both the human glutathioneS-transferase class mu and class theta enzymes (GSTM1and GSTT1) arepolymorphic with a variable ethnic distribution. These enzymes detoxifyreactive epoxides, including carcinogens produced by tobacco smoke. Becauseof this, the null polymorphism in the GSTM1 gene (coding for the glutathioneS-transferase class mu enzyme) has been studied widely as a possible sourceof inherited susceptibility to smoking-related lung cancer. The more recentlydescribed null polymorphism in the GSTT1 gene also could contribute to anincreased risk of smoking-related lung cancer. As the incidence of lungcancer is known to differ by ethnicity, we have conducted a case-controlstudy in the United States of 108 African-Americans (Blacks) and 60Mexican-Americans (Hispanics) with lung cancer and 132 African-American(Black) and 146 Mexican-American (Hispanic) controls to investigate theassociation of the GSTT1 and GSTM1 polymorphi sms with lung cancer inminority populations. In the unadjusted data, there was a borderlinesignificant association of the GSTM1 null polymorphism with lung cancer inMexican-Americans (odds ratio [OR] = 1.8, 95 percent confidence interval [CI]= 1.0-3.3 ) that was not observed in African-Americans. The GSTT1 nullpolymorphism also had a higher prevalence in cases than controls in bothracial/ethnic groups, but this increase was not statistically significant.When the data were analyzed using logistic regression controlling for age,gender, race, and smoking, no significant association of either trait withlung cancer was observed, with ORs for both traits of approximately 1.3.However, when the prevalence of individuals who were null for bothpolymorphisms was compared by case status, a significant interaction wasobserved. Logistic regression models showed the OR for the association oflung cancer and the presence of both null polymorphisms compared with one(either GSTT1 or GSTM1) or no null genotype to be 2.9 (P < 0.04). Theseresults suggest that there may be carcinogenic intermediates in cigarettesmoke that are substrates for both the GSTT1 and GSTM1 enzymes, and that lungcancer risk is increased more than additively for individuals who have bothGSTT1 and GSTM1 null polymorphisms. 相似文献
109.
110.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
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