全文获取类型
收费全文 | 32761篇 |
免费 | 3154篇 |
国内免费 | 1932篇 |
专业分类
耳鼻咽喉 | 315篇 |
儿科学 | 349篇 |
妇产科学 | 399篇 |
基础医学 | 3839篇 |
口腔科学 | 572篇 |
临床医学 | 4258篇 |
内科学 | 5073篇 |
皮肤病学 | 279篇 |
神经病学 | 1974篇 |
特种医学 | 1289篇 |
外国民族医学 | 27篇 |
外科学 | 3446篇 |
综合类 | 4952篇 |
现状与发展 | 12篇 |
一般理论 | 18篇 |
预防医学 | 2230篇 |
眼科学 | 749篇 |
药学 | 3463篇 |
27篇 | |
中国医学 | 1689篇 |
肿瘤学 | 2887篇 |
出版年
2024年 | 129篇 |
2023年 | 476篇 |
2022年 | 1262篇 |
2021年 | 1654篇 |
2020年 | 1249篇 |
2019年 | 1064篇 |
2018年 | 1144篇 |
2017年 | 1069篇 |
2016年 | 1025篇 |
2015年 | 1555篇 |
2014年 | 1788篇 |
2013年 | 1579篇 |
2012年 | 2454篇 |
2011年 | 2530篇 |
2010年 | 1654篇 |
2009年 | 1349篇 |
2008年 | 1827篇 |
2007年 | 1880篇 |
2006年 | 1848篇 |
2005年 | 1672篇 |
2004年 | 1344篇 |
2003年 | 1348篇 |
2002年 | 1193篇 |
2001年 | 649篇 |
2000年 | 596篇 |
1999年 | 569篇 |
1998年 | 344篇 |
1997年 | 375篇 |
1996年 | 311篇 |
1995年 | 280篇 |
1994年 | 238篇 |
1993年 | 173篇 |
1992年 | 199篇 |
1991年 | 164篇 |
1990年 | 152篇 |
1989年 | 98篇 |
1988年 | 90篇 |
1987年 | 80篇 |
1986年 | 61篇 |
1985年 | 61篇 |
1984年 | 58篇 |
1983年 | 22篇 |
1982年 | 26篇 |
1981年 | 23篇 |
1980年 | 16篇 |
1979年 | 14篇 |
1978年 | 11篇 |
1977年 | 9篇 |
1974年 | 9篇 |
1973年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
Itiswellknownthatcertaincytokinesplayapivotalroleinthedevelopmentoftraumaandshock.Tumornecrosisfactor(TNF)isapolypep-tiedcytokinesynthesizedinmonocytesandmacrophagesinresponsetolipopolysaccharide(LPS)stimulation-TherelationshipbetweenTNFandendotoxic-septicshockbecomesafocusoftheresearchofshockmediators[1'2].Alargeamountofexperimentalandclinicaldata[3-9JsuggestthatTNFplaysanimportantroleinthepathogenesisofendotoxic-septicshockbuttheprecisemechanismandtherelationshipofTNFtoshockseverityrem… 相似文献
42.
成人原发性肾病综合征血容量与肾素,醛固酮,心钠素的关系 总被引:2,自引:0,他引:2
探讨成人原发性肾病综合征(NS)血容量与肾素、醛固酮及心钠素的关系。方法 应用~(113)mInCl标记转铁蛋白稀释法测定血容量,放免法测定血浆激素水平。对水肿期NS28例、正常26例及其中NS缓解期随访18例进行检测。结果 (1)水肿期NS血容量与正常组无差别,血浆肾素活性(PRA)、血管紧张素Ⅱ(ATⅡ)、醛固酮(Ald)、心钠素(ANP)水平均较正常组高,白蛋白、各激素水平与血容量无显著相关;(2)缓解期与水肿期比较,总的血容量无差异,Ald、ANP显著降低,PRA、ATⅡ则无明显差异;(3)Ald与24小时尿排钠(UNaV)显著负相关。结论 Ald和ANP是NS钠排泄的主要调节因子。 相似文献
43.
探讨儿童间歇性深吸气症的诊断及治疗.方法 对我院1990~1996年以间歇性深吸气为主诉就诊的60例儿童进行病因、临床表现、诊断方法和主要治疗措施等方面的临床分析.结果 此症患儿有心理障碍和情绪因素的占63.3%,其中最重要的是家庭和学校环境因素的影响,习惯因素占20%.另外,还有气质因素的影响等.并提出本症的诊断依据.通过心理治疗,绝大多数病例可以治愈.结论 本症是一种较常见的心因性疾病,提出的诊断依据是实用的,心理治疗可获得满意疗效. 相似文献
44.
45.
46.
经尿道电切与气化切割和激光治疗前列腺增生症的疗效比较 总被引:11,自引:0,他引:11
目的 :比较经尿道电切前列腺术 (TURP) ,经尿道前列腺气化切除术 (TUVP)及经尿道接触式激光前列腺切除术 (TULP)的治疗效果。方法 :在 30 0 0例前列腺增生症患者中 ,按三种术式各随机抽取 2 0例术前条件具有可比性的患者 ,进行疗效比较。结果 :3种术式患者手术前后前列腺症状评分 (IPSS)、生活质量评分(QOL)、最大尿流率 (MFR)、剩余尿 (PVR)比较均得到显著改善 (P <0 .0 1) ,3组之间相比差异无显著性意义(P >0 .0 5 )。手术时间 :TUVP及TURP组明显短于TULP组 (P <0 .0 1) ,术中失血量及术后置管时间 :TUVP及TULP组明显少于TURP组 (P <0 .0 1)。TURP组术后继发感染、出血、暂时性尿失禁发生率少于TUVP及TULP组。结论 :3种术式治疗效果相同 ;TUVP操作简单、安全 ,对初学者来说尤其适宜 ;TURP仍为治疗BPH的金标准术式 相似文献
47.
L H Ren A V Vasil'ev A N Orkehov V V Tertov V A Tutel'ian 《Farmakologiia i toksikologiia》1989,52(5):44-46
Administration of alizole, berberine, pheonol and pheoniphlorine in doses of 30-100 micrograms/ml in the culture of the atherosclerotic human aortic intimal cells decreased the content of intracellular cholesterol by 35-41% and reduced the proliferative activity of the cells. In healthy donors administration of single doses of berberine and pheoniphlorine (0.9 g) increased the antiatherogenic potential of the serum which was estimated on the primary culture of the intimal cells. 相似文献
48.
A tumor-targeted and conditionally replicating oncolytic adenovirus vector expressing TRAIL for treatment of liver metastases. 总被引:3,自引:0,他引:3
Pavel Sova Xiao-Wei Ren Shaoheng Ni Kathrin M Bernt Jie Mi Nancy Kiviat André Lieber 《Molecular therapy》2004,9(4):496-509
We have constructed a new capsid-modified adenovirus (Ad) vector that specifically replicates in tumor cells and expresses TNF-related apoptosis-inducing ligand (TRAIL). The Ad capsid contains short-shafted fibers derived from Ad serotype 35, which allow for efficient infection of malignant tumor cells, and largely avoids innate toxicity after intravenous application. Replication-dependent homologous recombination in Ad genomes was used to achieve tumor-specific expression of Ad E1a (to mediate viral replication) and TRAIL (to mediate apoptosis and enhance release of progeny virus from infected cells). We demonstrated that our oncolytic vector (Ad5/35.IR-E1A/TRAIL) induced apoptosis in human tumor cell lines derived from colorectal, lung, prostate, and liver cancer. Both in vitro and in vivo tumor models showed efficient intratumoral spread of this vector. In a model for metastatic colon cancer, tail vein infusion of Ad5/35.IR-E1A/TRAIL resulted in elimination of preestablished liver metastases. Intravenous injection of this vector caused a transient elevation of serum glutamic pyruvic transaminase in tumor-bearing mice, which we attributed to factors released from apoptotic tumor cells. Liver histology analyzed at day 14 after virus injection did not show signs of hepatocellular damage. This new oncolytic vector represents a potentially efficient means for gene therapy of metastatic cancer. 相似文献
49.
Defective implant osseointegration under protein undernutrition: prevention by PTH or pamidronate. 总被引:1,自引:0,他引:1
Romain Dayer Isabelle Badoud René Rizzoli Patrick Ammann 《Journal of bone and mineral research》2007,22(10):1526-1533
Protein deficiency is associated with impaired titanium osseointegration. We studied whether systemic treatment with PTH or pamidronate could influence the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. PTH or pamidronate prevented the deleterious effects of protein undernutrition on bone microarchitecture close to the implant and on mechanical fixation. PTH even significantly improved implant osseointegration. INTRODUCTION: Protein deficiency is highly prevalent among elderly patients hospitalized in orthopedic wards. Reduced protein intake impairs titanium osseointegration in rats. Whether stimulator of bone formation or inhibitor of bone resorption could improve implant osseointegration under protein deprivation is not known. We studied the effects of systemic treatment with PTH or pamidronate on the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. MATERIALS AND METHODS: We measured the resistance to pull-out 1-mm-diameter titanium rods implanted into the proximal tibias of 49 adult female rats receiving a normal or an isocaloric low protein diet. After 2 wk on either diet, the implants were inserted, and the rats received PTH(1-34), pamidronate or saline vehicle for 8 wk. The tibias were removed for microCT morphometry, followed by the evaluation of pull-out strength. RESULTS: Pull-out strength was lower in rats fed an isocaloric low protein diet compared with rats fed a normal protein intake (-29%). PTH and pamidronate significantly increased pull-out strength in animals fed a normal or a low protein diet, the effect of PTH being of higher magnitude. The PTH- or pamidronate-mediated increase in pull-out strength was associated with significant increases of relative bone volume, bone-to-implant contact, and trabecular thickness, whereas trabecular spacing was reduced, in the vicinity of the implants. CONCLUSIONS: We confirmed that isocaloric low protein intake impairs titanium implant osseointegration. PTH or pamidronate prevented the deleterious effects of protein undernutrition and even significantly improved the implant osseointegration. These results indicate that systemic administration of PTH or pamidronate could be considered for preventing uncemented arthroplasty loosening in protein undernourished patients. 相似文献
50.