全文获取类型
收费全文 | 15808篇 |
免费 | 1009篇 |
国内免费 | 689篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 466篇 |
妇产科学 | 240篇 |
基础医学 | 2951篇 |
口腔科学 | 451篇 |
临床医学 | 1257篇 |
内科学 | 2238篇 |
皮肤病学 | 341篇 |
神经病学 | 736篇 |
特种医学 | 474篇 |
外国民族医学 | 6篇 |
外科学 | 1305篇 |
综合类 | 2687篇 |
现状与发展 | 2篇 |
预防医学 | 631篇 |
眼科学 | 211篇 |
药学 | 1897篇 |
2篇 | |
中国医学 | 655篇 |
肿瘤学 | 879篇 |
出版年
2024年 | 30篇 |
2023年 | 169篇 |
2022年 | 375篇 |
2021年 | 461篇 |
2020年 | 523篇 |
2019年 | 442篇 |
2018年 | 401篇 |
2017年 | 474篇 |
2016年 | 496篇 |
2015年 | 543篇 |
2014年 | 886篇 |
2013年 | 1027篇 |
2012年 | 828篇 |
2011年 | 980篇 |
2010年 | 763篇 |
2009年 | 839篇 |
2008年 | 778篇 |
2007年 | 862篇 |
2006年 | 790篇 |
2005年 | 743篇 |
2004年 | 660篇 |
2003年 | 592篇 |
2002年 | 397篇 |
2001年 | 378篇 |
2000年 | 351篇 |
1999年 | 251篇 |
1998年 | 289篇 |
1997年 | 282篇 |
1996年 | 281篇 |
1995年 | 295篇 |
1994年 | 202篇 |
1993年 | 179篇 |
1992年 | 100篇 |
1991年 | 114篇 |
1990年 | 91篇 |
1989年 | 51篇 |
1988年 | 57篇 |
1987年 | 44篇 |
1986年 | 31篇 |
1985年 | 74篇 |
1984年 | 66篇 |
1983年 | 55篇 |
1982年 | 40篇 |
1981年 | 37篇 |
1980年 | 33篇 |
1979年 | 34篇 |
1978年 | 24篇 |
1977年 | 25篇 |
1976年 | 16篇 |
1975年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
目的 :观察老年冠心病心功能不全患者血浆白细胞介素 6 (interleukin - 6 ,IL - 6 )浓度的变化。方法 :选择老年冠心病心功能不全患者 48例、心功能正常者 15例及健康老年人 30例 ,采用酶联免疫吸附法测定其血浆IL - 6浓度。结果 :冠心病心功能不全组血浆IL - 6浓度较冠心病心功能正常组及健康对照组明显增高 (均P <0 .0 5 ) ,而冠心病心功能正常组与健康对照组之间无明显差异 (P >0 .0 5 ) ;血浆IL - 6浓度与左室射血分数呈负相关 (r =- 0 .6 0 ,P <0 .0 1) ;因心功能不全恶化再入院患者血浆IL - 6浓度高于未再入院患者 (P <0 .0 1)。结论 :IL - 6具有判断病情、评价预后的价值 相似文献
92.
五种免疫相关性心血管疾病的免疫学研究 总被引:4,自引:0,他引:4
对扩张型心肌病、风湿性心脏病,原发性高血压,冠心病及肥厚型心肌病进行外周血清可溶性白细胞介素2受体,T淋巴细胞亚群及自然杀伤细胞活性的检测,并与健康对照组比较,结果显示:DCM组,RHD组及EHT组的sIL-2R明显高于NC组,而DCM、RHD风湿活动组的NK活性低于NC组,EHT组NK活性高于NC组。 相似文献
93.
Kalyuzhin OV Nelyubov MV Kalyuzhina EV Kuzovlev FN Shkalev MV 《Bulletin of experimental biology and medicine》2002,134(3):281-283
Effects of 11 original glycoside derivatives of muramyl dipeptide on the production of interleukin-1 and tumor necrosis factor by mouse peritoneal macrophages were studied. The relationship between macrophage activation evaluated by induction of these cytokines and configuration of glycoside bond and aglycon structure of MDP was revealed. 相似文献
94.
95.
T. Suzuki N. Nagano H. Ono H. Fukuda 《Journal of neural transmission (Vienna, Austria : 1996)》1990,79(1-2):1-9
Summary The effects of morphine-HCl (MOR), methionine-enkephalin (ME) and dynorphin1–13 (DYN) on spinal and spino-bulbo-spinal (SBS) reflexes were studied. Although spinal intrathecal administration of MOR (15g) did not produce any apparent effect on these reflexes, systemically administered MOR (3mg/kg i.v.) reduced the electrical toe stimulation-induced SBS reflex. Furthermore, MOR (3mg/kg i.v.) increased the polysynaptic reflex induced by electrical stimulation of low-threshold dorsal root afferents in intact (non-spinal) rats, but not in spinal rats. Intrathecally administred DYN (0.5 and 5 g) reduced both the electrical toe stimulation-induced spinal and SBS reflexes, while ME (15g) only reduced the SBS reflex. These results indicate the physiological multiplicity of spinal opioid receptors. MOR may affect supraspinal nuclei but not the spinal pathway which possesses MOR-sensitive opioid receptors, whereas ME and DYN affect spinal opioid peptide receptors and modulate the reflex activities in which they participate. 相似文献
96.
H. Okuno Y. Kitao M. Takasu H. Kano K. Kunieda T. Seki Y. Shiozaki Y. Sameshima 《European journal of clinical pharmacology》1990,39(4):365-367
Summary The depressant effect of interferon- on drug metabolizing activity in the liver has been investigated in 12 patients with chronic active hepatitis B. 7-methoxy-coumarin (7-MC) O-demethylase and 7-ethoxycoumarin (7-EC) O-deethylase, in specimens obtained by liver biopsy, were measured before and after interferon treatment. 7-MC and 7-EC O-dealkylase activity were significantly reduced after interferon treatment, from 13.4 to 9.24 nmol·g–1 liver·min–1, and from 3.22 to 2.16 nmol·g–1 liver·min–1, respectively. The magnitude of the fall varied widely between individual patients. The study provides the first direct evidence that interferon- can impair the activity of drug metabolizing enzymes in the human liver. 相似文献
97.
H Yanagawa S Sone A Okubo K Fukuta Y Nishioka T Ogura 《Japanese journal of clinical oncology》1990,20(4):356-363
Interferon-gamma (IFN-gamma) acts on a large array of different types of cell and has potent immunomodulatory activities besides cytotoxic effects on tumors. In a phase I study, some immunologic parameters of blood mononuclear cells from healthy volunteers who received intramuscular injections of natural human IFN-gamma were analyzed. The percentage of Leu-11a positive cells, natural killer (NK) activity, lymphokine (interleukin-2)-activated killer (LAK) activity and monokine production were measured either in blood mononuclear cells or in purified samples of lymphocytes or monocytes of the donors before and 24 h after IFN-gamma injection. After IFN-gamma injection, the percentage of Leu-11a positive cells and the LAK activity in the blood were significantly reduced, but NK activity and monokine production remained unchanged. These findings suggest that in vivo IFN-gamma acts directly or indirectly on Leu-11a positive cells and reduces LAK activity by changing the recruitment of LAK precursors in the blood. 相似文献
98.
Objective: To study the treatment of experimental metastatic lung carcinoma by intratracheal injection of IL-18 gene recombinant adenovirus. Methods: (1)The mouse IL-18 mRNA was detected by RT-PCR, and the concentration of 1L-18 and associated cytokines in lung lavages and blood were determined by ELISA at different time points after intratracheal injection of IL-18 recombinant adenovirus. (2)The lung metastasis nodes, mouse survival periods and survival rates were evaluated. NK activity and CTL activity were determined by 51Cr 4 h release method. Results: (1)IL-18 mRNA was detectable in lung tissue 6 h after intratracheal use of IL-18 recombinant adenovirus, and the concentration of IL-18 in lung lavage was higher than that in peripheral blood. Neither IL-18 mRNA nor IL-18 was detectable in control group. (2) Intmtmcheal use of IL-18 recombinant adenovirus resulted in increased CTL and NK activity, longer survival time and higher survival rates compared with the control group, showing significant therapeutic effect on experimental lung metastasis. Conclusion: Intratracheal use of adenovirus vector containing IL-18 gene has therapeutic effect on the lung metastasis, denoting that gene therapy of lung diseases could be applied through airway directly with recombinant adenovirus. 相似文献
99.
重组人白细胞介素-13对巨核细胞系-Dami细胞原癌基因c-mpl表达的影响 总被引:1,自引:0,他引:1
目的:研究重组人白细胞介素-13(rhIL-13)对巨核细胞系-Dami细胞原癌基因c-mpl表达的影响.方法:实验组细胞培养系统中分别加入25 ng/ml,50 ng/ml,100ng/ml rhIL-13,对照组不加任何细胞因子.用RT-PCR法检测c-mpl mRNA的表达.结果:经25 ng/ml、50 ng/ml、100ng/ml rhIL-13处理过的实验组Dami细胞较之对照组其c-mpl mRNA的表达分别提高24.8%、27.9%和31.5%.结论:rhIL-13增强了Dami细胞原癌基因c-mpl表达;rhIL-13促进Dami细胞增殖的部分机制可能是通过上调c-mpl的表达来实现的. 相似文献
100.
目的:探讨大鼠中脑导水管周围灰质(PAG)内内源性强啡肽对神经降压素(NT)镇痛作用的影响。方法:以钾离子透入法引起大鼠甩尾反应的电流强度(mA)为痛行为反应的指标,观察向PAG内注入NT,抗神经降压素血清和抗强啡肽A1-13血清对动物痛阈的影响。结果:PAG内注入NT后,大鼠痛阈明显升高;注入抗神经降压素血清后,大鼠痛阈则明显降低,而注入抗强啡肽血清后,对NT的镇痛效应无显著影响,结论:PAG内NT在痛觉调制中发挥着重要的作用,且其作用不依赖于PAG内的内源性强啡肽。 相似文献