全文获取类型
收费全文 | 29030篇 |
免费 | 2314篇 |
国内免费 | 254篇 |
专业分类
耳鼻咽喉 | 358篇 |
儿科学 | 724篇 |
妇产科学 | 5007篇 |
基础医学 | 1434篇 |
口腔科学 | 350篇 |
临床医学 | 2961篇 |
内科学 | 3794篇 |
皮肤病学 | 342篇 |
神经病学 | 1195篇 |
特种医学 | 345篇 |
外科学 | 4941篇 |
综合类 | 2529篇 |
现状与发展 | 1篇 |
一般理论 | 4篇 |
预防医学 | 4169篇 |
眼科学 | 141篇 |
药学 | 1894篇 |
17篇 | |
中国医学 | 266篇 |
肿瘤学 | 1126篇 |
出版年
2024年 | 62篇 |
2023年 | 854篇 |
2022年 | 1266篇 |
2021年 | 1854篇 |
2020年 | 1698篇 |
2019年 | 1713篇 |
2018年 | 1655篇 |
2017年 | 1504篇 |
2016年 | 1393篇 |
2015年 | 1222篇 |
2014年 | 2233篇 |
2013年 | 2456篇 |
2012年 | 1473篇 |
2011年 | 1635篇 |
2010年 | 1186篇 |
2009年 | 1367篇 |
2008年 | 1176篇 |
2007年 | 1089篇 |
2006年 | 988篇 |
2005年 | 792篇 |
2004年 | 690篇 |
2003年 | 521篇 |
2002年 | 414篇 |
2001年 | 350篇 |
2000年 | 336篇 |
1999年 | 240篇 |
1998年 | 225篇 |
1997年 | 188篇 |
1996年 | 137篇 |
1995年 | 128篇 |
1994年 | 108篇 |
1993年 | 80篇 |
1992年 | 58篇 |
1991年 | 56篇 |
1990年 | 44篇 |
1989年 | 40篇 |
1988年 | 38篇 |
1987年 | 32篇 |
1986年 | 18篇 |
1985年 | 50篇 |
1984年 | 36篇 |
1983年 | 25篇 |
1982年 | 31篇 |
1981年 | 20篇 |
1980年 | 19篇 |
1979年 | 16篇 |
1978年 | 21篇 |
1977年 | 14篇 |
1975年 | 13篇 |
1973年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
What Is Sufficient Evidence for the Reliability and Validity of Patient-Reported Outcome Measures? 总被引:1,自引:0,他引:1
82.
Summary Intracranial haemorrhage due to rupture of an arteriovenous malformation (AVM) during pregnancy is a rare but serious condition that warrants prompt recognition. Once the diagnosis is made, the management is primarily based on neurosurgical rather than obstetric considerations. Due to its rarity, no definitive guidelines exist, and the best time to perform elective surgery (i.e., at presentation or at completion of the pregnancy) is ill-defined. This report describes three patients recently treated at our institution who had AVMs that ruptured during pregnancy. These cases well summarize the difficulties encountered in treating such patients. The diagnostic as well as the therapeutic implications of this condition are discussed. 相似文献
83.
低剂量阿司匹林在辅助生育技术中的应用 总被引:2,自引:0,他引:2
目的 探讨在进行体外受精 -胚胎移植 ( IVF-ET)或卵母细胞浆内单精子注射 ( ICSI)患者口服低剂量阿司匹林对治疗结果的影响。 方法 IVF或 ICSI治疗的 3 2 4个 ET周期 ,分为是否服用阿司匹林两组 ,分别统计患者注射人绒毛膜促性腺激素 ( h CG)时子宫内膜厚度及 ET胚胎数 ,比较两组的胚胎种植率、临床妊娠率及流产率 ,并进行统计学处理。 结果 两组在注射 h CG日内膜平均厚度、ET中优质胚胎的比率及流产率均无显著性差异 ;未服用阿司匹林组的 ET胚胎数明显多于服用组 ( P<0 .0 1 ) ,而前者的种植率、临床妊娠率却明显低于后者 ( P<0 .0 1 )。 结论 低剂量阿司匹林在 IVF-ET或ICSI的辅助生殖治疗中能有效地提高胚胎种植率 ,增加患者的临床妊娠率 相似文献
84.
Smoking in Pregnancy and Parenthood: What is the Role of Depression, Anxiety and Nicotine Addiction?
Leona Bull Ronan Burke Siobhan Walsh Emma Whitehead 《Early child development and care》2003,173(2):349-356
This paper presents some of the findings from the Smoking in Pregnancy study of attitudes towards smoking among pregnant women, mothers of young children and their partners in East Surrey. As part of the study, respondents completed a General Health Questionnaire to identify mental health difficulties and, if they were smoking at the time of the study, they also completed the Fagerstrom nicotine addiction test. Eleven female respondents had high scores on the General Health Questionnaire, suggesting symptoms of depression, anxiety and/or social dysfunction for these women. There was no evidence that smokers were suffering from greater mental health difficulties than ex-smokers or non-smokers. However, the General Health Questionnaire scores of smokers were positively associated with their level of nicotine dependence. Furthermore, when General Health Questionnaire scores of all respondents were compared with self-reported health status there was a marked discrepancy suggesting under-reporting of symptoms by women. 相似文献
85.
目的:研究阻断CD86协同刺激分子对自然流产模型孕鼠母胎界面Caspase-3、laminin B和PAI-1的表达及对妊娠结局的影响。方法:实验组于妊娠第4.5天腹腔注射大鼠抗小鼠CD86单抗,实验对照组注射大鼠同型IgG2b,正常妊娠组不作任何处理。于妊娠第13.5天计算胚胎吸收率,用免疫组化测定Caspase-3、laminin B和PAI-1的表达,并进行图像分析、检测免疫组化染色灰度值(A)。结果:①实验组的胚胎吸收率显著低于实验对照组(P<0.05);②实验组中Caspase-3蛋白灰度值明显高于实验对照组(P<0.05),实验组中laminin B和PAI-1蛋白灰度值均明显低于实验对照组(P<0.05)。结论:妊娠早期阻断CD86协同刺激分子可使母胎界面中的Caspase-3、laminin B和PAI-1分别通过各自不同的途径发挥免疫耐受作用并且使自然流产模型孕鼠的胚胎吸收率降低至正常妊娠水平。 相似文献
86.
经阴道彩色多普勒诊断未破裂型输卵管妊娠 总被引:1,自引:1,他引:0
本文介绍经阴道彩色多普勒诊断未破裂型输卵管妊娠26例,13例经手术及病理检查证实,13例经临床确诊,符合25例,诊断符合率96.15%;误诊1例,误诊率3.85%。经阴道彩色多普勒检查其二维图像清晰,彩色血流灵敏,能更早发现输卵管妊娠包块内特异的滋养层周围血流及同侧卵巢的黄体血流,使输卵管妊娠在破裂前就能作出诊断,具有较高的临床应用价值。 相似文献
87.
目的:探讨妊娠黄体瘤(LP)的误诊原因。方法:对1例典型LP病例进行全面病理学检查和组化及免疫组化染色,与正常卵巢黄体进行对比分析,并复习文献。结果:LP均发生于妊娠后期,临床无明显自觉症状,其病理形态学、组织学、免疫组化反应与正常卵巢黄体相似。多在剖腹产时偶然发现而误为卵巢肿瘤。结论;LP为妊娠后期卵巢黄素化细胞的结节状增生,并非真性肿瘤。妊娠期出现卵巢明显增大,应首先考虑到本病的可能性。必要时术中可作活检,以避免误切卵巢。 相似文献
88.
妊娠肝内胆汁淤积症患者胎盘组织中血管内皮生长因子的表达 总被引:2,自引:0,他引:2
目的观察血管内皮生长因子(VEGF)在妊娠肝内胆汁淤积症(ICP)胎盘中的表达.方法采用免疫组织化学方法,检测25例正常妊娠胎盘(对照组)和25例ICP胎盘(ICP组)中VEGF的水平.结果 VEGF在正常妊娠胎盘和ICP胎盘中分布基本一致,分布在滋养细胞、血管及绒毛间质.在ICP组VEGF为轻度表达占76%,中度表达占24%,无重度表达;而在对照组VEGF轻度表达占24%,中度表达占44%,重度表达占32%.ICP组中VEGF表达明显低于对照组(P<0.01).结论 VEGF在胎盘中主要由绒毛滋养细胞分泌,ICP胎盘中VEGF的减少可能与胎盘血管生成减少及胎盘滋养叶细胞浸入异常有关,在ICP发病中占有一定的地位. 相似文献
89.
J. A. Kobashigawa L. W. Miller S. D. Russell G. A. Ewald M. J. Zucker L. R. Goldberg H. J. Eisen K. Salm D. Tolzman J. Gao W. Fitzsimmons R. First 《American journal of transplantation》2006,6(6):1377-1386
The most advantageous combination of immunosuppressive agents for cardiac transplant recipients has not yet been established. Between November 2001 and June 2003, 343 de novo cardiac transplant recipients were randomized to receive steroids and either tacrolimus (TAC) + sirolimus (SRL), TAC + mycophenolate mofetil (MMF) or cyclosporine (CYA) + MMF. Antilymphocyte induction therapy was allowed for up to 5 days. The primary endpoint of >/=3A rejection or hemodynamic compromise rejection requiring treatment showed no significant difference at 6 months (TAC/MMF 22.4%, TAC/SRL 24.3%, CYA/MMF 31.6%, p = 0.271) and 1 year (p = 0.056), but it was significantly lower in the TAC/MMF group when compared only to the CYA/MMF group at 1 year (23.4% vs. 36.8%; p = 0.029). Differences in the incidence of any treated rejection were significant (TAC/SRL = 35%, TAC/MMF = 42%, CYA/MMF = 59%; p < 0.001), as were median levels of serum creatinine (TAC/SRL = 1.5 mg/dL, TAC/MMF = 1.3 mg/dL, CYA/MMF = 1.5 mg/dL; p = 0.032) and triglycerides (TAC/SRL = 162 mg/dL, TAC/MMF = 126 mg/dL, CYA/MMF = 154 mg/dL; p = 0.028). The TAC/SRL group encountered fewer viral infections but more fungal infections and impaired wound healing. These secondary endpoints suggest that the TAC/MMF combination appears to offer more advantages than TAC/SRL or CYA/MMF in cardiac transplant patients, including fewer >/=3A rejections or hemodynamic compromise rejections and an improved side-effect profile. 相似文献
90.
A M Abdel Gader A A Al-Mishari S A Awadalla N M Buyuomi T Khashoggi M Al-Hakeem 《International journal of gynaecology and obstetrics》2006,95(3):248-253
OBJECTIVE: To clarify the role played by tissue factor pathway inhibitor (TFPI) in pregnancy hypertension. METHODS: Using enzyme-linked immunosorbent assays, hemostatic measurements were obtained for women with pre-eclampsia (n=51), nonproteinuric hypertension of pregnancy (n=62), postpartum pre-eclampsia 24 h after childbirth (n=31), and no hypertension (healthy pregnant controls, n=100). RESULTS: There was a significant increase in circulating free TFPI levels in women with pre-eclampsia (9.7+/-6.2 ng/mL) or nonproteinuric hypertension of pregnancy (8.3+/-5.3 ng/mL) compared with healthy controls (5.3+/-2.1 ng/mL). In women with pre-eclampsia the levels remained elevated after placental delivery (10.6+/-4.0 ng/mL). Free protein S levels were significantly higher in women with pre-eclampsia (40.0%+/-10.7%), nonproteinuric hypertension of pregnancy (37.1%+/-12.5%), or postpartum pre-eclampsia (39.3%+/-9.1%) than in healthy pregnant controls (32.2%+/-8.5%). CONCLUSION: Increased levels of the physiologically active free forms of TFPI and free protein S, 2 coagulation inhibitors, may protect women with pregnancy-induced hypertension from the risks of hemostatic activation. 相似文献