全文获取类型
收费全文 | 35259篇 |
免费 | 3657篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 211篇 |
儿科学 | 1135篇 |
妇产科学 | 969篇 |
基础医学 | 4955篇 |
口腔科学 | 742篇 |
临床医学 | 4208篇 |
内科学 | 6358篇 |
皮肤病学 | 583篇 |
神经病学 | 3050篇 |
特种医学 | 1547篇 |
外国民族医学 | 4篇 |
外科学 | 4467篇 |
综合类 | 795篇 |
一般理论 | 43篇 |
预防医学 | 4293篇 |
眼科学 | 885篇 |
药学 | 2626篇 |
中国医学 | 46篇 |
肿瘤学 | 2031篇 |
出版年
2022年 | 271篇 |
2021年 | 612篇 |
2020年 | 330篇 |
2019年 | 579篇 |
2018年 | 607篇 |
2017年 | 475篇 |
2016年 | 524篇 |
2015年 | 567篇 |
2014年 | 771篇 |
2013年 | 1158篇 |
2012年 | 1648篇 |
2011年 | 1617篇 |
2010年 | 963篇 |
2009年 | 880篇 |
2008年 | 1469篇 |
2007年 | 1547篇 |
2006年 | 1543篇 |
2005年 | 1476篇 |
2004年 | 1460篇 |
2003年 | 1354篇 |
2002年 | 1279篇 |
2001年 | 1192篇 |
2000年 | 1208篇 |
1999年 | 1045篇 |
1998年 | 472篇 |
1997年 | 436篇 |
1996年 | 407篇 |
1995年 | 338篇 |
1994年 | 367篇 |
1993年 | 357篇 |
1992年 | 820篇 |
1991年 | 790篇 |
1990年 | 783篇 |
1989年 | 678篇 |
1988年 | 711篇 |
1987年 | 667篇 |
1986年 | 616篇 |
1985年 | 666篇 |
1984年 | 538篇 |
1983年 | 425篇 |
1982年 | 282篇 |
1981年 | 283篇 |
1980年 | 262篇 |
1979年 | 466篇 |
1978年 | 347篇 |
1977年 | 261篇 |
1976年 | 276篇 |
1974年 | 285篇 |
1973年 | 262篇 |
1972年 | 268篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
La Creis R Kidd K Woodson P R Taylor D Albanes J Virtamo J A Tangrea 《European journal of cancer prevention》2003,12(4):317-320
Glutathione-S-transferase (GST) genes encode a family of detoxification enzymes that offer protection against endogenous and exogenous sources of reactive oxygen species (ROS). Germline variations in GST genes may alter the catalytic efficiency of GST isoenzymes leading to a potential increase in susceptibility to the genotoxic effects of ROS and electrophilic substances. A nested case-control study design was used to examine the association between the polymorphic GST genes and prostate cancer risk among Finnish male smokers of the ATBC Cancer Prevention Study. A case-case analysis was used to determine the association between these genetic polymorphisms and prostate cancer progression. Germline DNA was obtained from 206 prostate cancer cases and 194 controls frequency matched on age, intervention group and study clinic. Cases and controls were genotyped for three GST genes using MALDI-TOF mass spectrometry or multiplex polymerase chain reaction (PCR). Relative to the wild-type genotype, we observed a 36% reduction in prostate cancer risk associated with the GST-M1-null genotype (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.43, 0.95). Unlike GST-M1, GST-T1-null (OR 0.74, 95% CI 0.42, 1.33) and GST-P1*B (OR 1.10, 95% CI 0.72, 1.69) were not strongly associated with prostate cancer risk. We did not observe any significant associations between the selected polymorphic GST genes and tumour grade or stage. In conclusion, we did not observe a direct association between polymorphic GST-T1 or GST-P1 and prostate cancer risk. Our observation of a relatively strong inverse association between the GST-M1-null genotype and prostate cancer risk needs to be confirmed in larger association studies. 相似文献
4.
5.
Kevin L Taylor Rhonda K Oates Ron Grane Douglas W Leaman Ernest C Borden Daniel J Lindner 《Journal of interferon & cytokine research》2006,26(5):353-361
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation. 相似文献
6.
Sarah A. Taylor Jacqueline Benedetti David Schuller Stephen P. Richman Goronwy O. Broun Alexander Hantel 《Investigational new drugs》1993,11(2-3):227-229
Summary Twenty-two patients with recurrent or metastatic squamous cell carcinoma of the head and neck were treated with piroxantrone 150 mg/m2 intravenously every 21 days. There were no objective responses. The 95% upper confidence bound for response is 15%. Primary toxicity was hematologic. 相似文献
7.
Facilitated uptake of zinc into human erythrocytes. Relevance to the treatment of sickle-cell anaemia 总被引:1,自引:0,他引:1
R C Hider L Ejim P D Taylor R Gale E Huehns J B Porter 《Biochemical pharmacology》1990,39(6):1005-1012
The ability of a number of heterocyclic metal chelators to deliver zinc into red cells, to release the liganded zinc to haemoglobin and thereby cause a left shift in the oxygen dissociation curve of intact red cells has been investigated. Incubation of neutrally charged zinc-pyrone and zinc-pyridin-2-one complexes with red cells led to the rapid accumulation of zinc within cells, whereas unliganded zinc in the form of zinc acetate, zinc chloride or zinc sulphate accumulated only slowly. The rate at which zinc was delivered to red cells by pyrone and pyridin-2-one ligands increased with increasing lipid solubility of the ligands. The uptake of zinc into both normal adult and sickle red cells was associated with a dose-dependent increase in the oxygen affinity of haemoglobin. The degree of left shift in the oxygen dissociation curve following the incubation of red cells with zinc-pyrone and -pyridin-2-one complexes suggests that these complexes may find application as agents to increase the oxygen affinity of haemoglobin in sickle cell disease and thereby decrease the probability of intravascular sickling at low tissue oxygen tensions. Ethylmaltol appears to be a particularly useful agent due to its known low toxicity. 相似文献
8.
M B Taylor 《Postgraduate medicine》1991,89(8):40-2, 45-7
The spectrum of acne vulgaris is wide, ranging from minor comedones to devastating nodules and cysts. Appropriate therapy requires an understanding of the various types of lesions, their pathophysiology, and the rationale for treatment. Good patient rapport and communication are important, and close follow-up is necessary until the treatment regimen has stabilized. Timely referral to a dermatologist is essential when therapy is not effective. With effort, the treatment of acne can be quite rewarding for both patient and physician. 相似文献
9.
32nd Annual Meeting of the Scandinavian Society for Psychopharmacology Copenhagen, Denmark April 10–12, 1991 Abstracts 相似文献
10.
Patrick J. Taylor 《Canadian Medical Association journal》1991,145(10):1362-1363