全文获取类型
收费全文 | 78912篇 |
免费 | 4877篇 |
国内免费 | 2344篇 |
专业分类
耳鼻咽喉 | 347篇 |
儿科学 | 962篇 |
妇产科学 | 778篇 |
基础医学 | 4693篇 |
口腔科学 | 345篇 |
临床医学 | 11241篇 |
内科学 | 25534篇 |
皮肤病学 | 121篇 |
神经病学 | 3534篇 |
特种医学 | 5743篇 |
外国民族医学 | 2篇 |
外科学 | 8205篇 |
综合类 | 13588篇 |
现状与发展 | 6篇 |
预防医学 | 2098篇 |
眼科学 | 485篇 |
药学 | 5325篇 |
54篇 | |
中国医学 | 2476篇 |
肿瘤学 | 596篇 |
出版年
2024年 | 104篇 |
2023年 | 1105篇 |
2022年 | 1831篇 |
2021年 | 3225篇 |
2020年 | 2890篇 |
2019年 | 2439篇 |
2018年 | 2504篇 |
2017年 | 2265篇 |
2016年 | 2372篇 |
2015年 | 2584篇 |
2014年 | 5453篇 |
2013年 | 5288篇 |
2012年 | 4510篇 |
2011年 | 5002篇 |
2010年 | 4149篇 |
2009年 | 4081篇 |
2008年 | 4233篇 |
2007年 | 4406篇 |
2006年 | 3933篇 |
2005年 | 3299篇 |
2004年 | 2627篇 |
2003年 | 2232篇 |
2002年 | 1874篇 |
2001年 | 1738篇 |
2000年 | 1318篇 |
1999年 | 1146篇 |
1998年 | 1200篇 |
1997年 | 1153篇 |
1996年 | 876篇 |
1995年 | 862篇 |
1994年 | 704篇 |
1993年 | 645篇 |
1992年 | 562篇 |
1991年 | 477篇 |
1990年 | 391篇 |
1989年 | 342篇 |
1988年 | 332篇 |
1987年 | 296篇 |
1986年 | 234篇 |
1985年 | 289篇 |
1984年 | 227篇 |
1983年 | 136篇 |
1982年 | 182篇 |
1981年 | 151篇 |
1980年 | 105篇 |
1979年 | 108篇 |
1978年 | 74篇 |
1977年 | 60篇 |
1976年 | 49篇 |
1975年 | 30篇 |
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
81.
Nobuhiko Joki Hiroki Hase Yuri Tanaka Yasunori Takahashi Tomokatsu Saijyo Hiroyaou Ishikawa Yoji Inishi Yoshihiko Imamura Hisao Hara Taro Tsunoda Masato Nakamura 《Nephrology, dialysis, transplantation》2006,21(6):1633-1639
BACKGROUND: In patients with chronic kidney disease (CKD), although strong associations have been observed between malnutrition and atherosclerosis, the relationship between serum albumin concentration and angiographic changes of coronary artery disease (CAD) remains poorly explored. The goal of the present study was, in patients with CKD, to clarify the relationship between the angiographic severity of CAD and serum albumin concentration reflecting either inflammation or nutrition or both. METHODS: In this study, 100 end-stage renal disease (ESRD) patients were enrolled, who commenced long-term dialysis therapy at our hospital and underwent coronary angiography within 3 months of the first haemodialysis (HD) session. Mean age was 63+/-11 years, 20% of the subjects were female and 62% had diabetes. Severity of CAD was evaluated in terms of (i) number of vessels exhibiting CAD (>or=75% stenosis) and (ii) Gensini score (GS). Clinical characteristics and laboratory findings were recorded at initiation of long-term HD therapy. We then evaluated a possible association with the presence and degree of CAD. RESULTS: Sixty-four patients exhibited signs of CAD. Forty-one among them (64%) had multivessel disease. On univariate logistic regression analysis, age, diabetes and hypoalbuminaemia were significantly associated with multivessel CAD. Univariate linear regression analysis demonstrated a positive correlation of age and diabetes with GS, and an inverse correlation of BMI and serum albumin level with GS. Stepwise regression analysis showed age and serum albumin level to be independently associated with multivessel CAD and GS. The ROC curves demonstrated best cut-off levels of age and albumin for predicting multivessel CAD to be 70 years and 3.15 g/dl, respectively. CONCLUSION: Hypoalbuminaemia at the initiation of dialysis is an important predictor of advanced CAD, particularly in male and in diabetic patients. It may reflect mainly a state of inflammation. However, malnutrition as a confounding factor cannot be entirely excluded. 相似文献
82.
冠状动脉瘘的诊治及新进展 总被引:2,自引:0,他引:2
冠状动脉瘘是一种罕见的冠状动脉畸形,绝大多数属于先天性畸形,极少数可由后天因素引起。由于冠状动脉血流向有关心腔、血管异常分流,导致引流部位负荷加重、瘘远端心肌缺血而引起相应临床症状。目前,绝大多数冠状动脉瘘已能由超声心动图明确诊断并可经内科介入技术或外科手术治愈。 相似文献
83.
三磷酸腺苷结合盒运转体A1与颈动脉粥样硬化斑块的关系 总被引:4,自引:0,他引:4
目的 探讨三磷酸腺苷结合盒运转体A1(ATP binding cassette transporter A1,ABCA1)在人颈动脉粥样硬化斑块中的表达变化及作用机制.方法 收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本(对照组),采用RT-PCR测定ABCA1 mRNA和视黄酸X受体α(RXRα)mRNA表达水平,并采用Western Blot检测ABCA1及RXRα的蛋白表达水平.24例人颈动脉粥样硬化斑块标本按病理分级,比较病理组织为Ⅲ级和Ⅰ级动脉粥样硬化组织间ABCA1 mRNA、RXRαmRNA表达水平及蛋白表达水平.结果 颈动脉粥样硬化斑块组的ABCA1 mRNA(0.79±0.04)和RXRα mRNA(0.73±0.04)表达与对照组相比上调,差异有统计学意义(P<0.05);ABCA1 mRNA与RXRα mRNA增加水平相关(P<0.05);颈动脉粥样硬化斑块的ABCA1蛋白表达(0.22±0.03)下调水平与对照组(0.53±0.03)相比差异有统计学意义(P<0.05);Ⅲ级和Ⅰ级动脉硬化斑块ABCA1mRNA、RXRα mRNA及蛋白表达水平差异有统计学意义(P<0.05).结论 ABCA1及RXRα蛋白表达水平下调可能是进展性动脉粥样硬化损害的关键因素. 相似文献
84.
经皮冠状动脉腔内成形术(PTCA)是近30年来治疗冠心病的主要技术之一,其相应的护理技术在过去近10年里有着明显的改进。本文以穿刺股动脉途径为重点综述国外PTCA术后留置动脉鞘管的护理进展:动脉外鞘管拔除责任者、拔除时间、拔管后局部压迫方法等内容,旨在提升PTCA术后的护理质量。 相似文献
85.
Uday Eknathrao Jadhav M.Ch. Raghavendra Chikkatur M.Ch. Rajesh Parida M.Ch. Susheel Kumar M.Ch. Vinod Ahuja M.Ch. Ashish Agrawal MS Anil Tendolkai M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(2):116-120
Introduction Coronary artery bypass grafting (CABG) associated with Endarterectomy is a high risk procedure. After the first report of
coronary endarterectomy by Bailey et al in 1951, the preference for this surgical procedure was decreased due to increased
morbidity and mortality In patients with total or subtotal large coronary artery obstructions in which there is no possibility
to receive a conduit as graft for myocardial revascularisation, endarterectomy remains the procedure of choice. This study
was designed to study early and midterm results of off pump coronary artery endarterectomy.
Methods Of 172 Consecutive Off Pump CABG done at our institution from Jan 2003 to July 2005, 22 patients underwent supplementary coronary
endarterectomy. 16 patients had chronic stable angina 4 had unstable angina two required emergency CABG with endarterectomy
following perioperative infarction. The mean ejection fraction was 29.2±4.3 and all of the patients were in New York Heart
Association (NYHA) III or IV. All patients were planned for complete total arterial revascularisation using Left Internal
Mammary Artery (LIMA). Right Internal Mammary Artery (RIMA), Radial composite “Y” graft, Two patients operated for periop
infarct received vein graft. In 16 patients closed endarterectomy was done in five patients double endarterectomy in single
vessel was done to chase the plaque distally, in one patient open left anterior descending (LAD) endarterectomy with vein
patch reconstruction was performed.
Results There were no deaths. None of the procedures were converted to on pump operation. All endarterectomies and bypasses were performed
on Beating Heart, all patients were completely revascularised. Peri operative cardiac enzymes studied showed no significant
rise in the Creatinine Phoshpokinase (CPK)-Creatinine Phosphokinase myocardial Band (CPK-MB). The mean postoperative Ejection
Fraction (EF) was 36.7%±7.2% which was significantly higher than the Preoperative one (p<.05). At the end of four months to
one and half year 22 patients were in NYHA class I to II and all were angina free in canadian cardiovascular society class.f
Conclusions Coronary End Arterectomy without cardiopulmonary bypass can be performed in patients who are expected to benefit from complete
revascularisation. It can be performed with closed as well as open method. However to achieve complete endarterectomy by closed
technique in some patients it is essential to chase the plaque. Early and mid term results are encouraging. 相似文献
86.
进展性卒中与脑动脉狭窄的脑血管造影研究 总被引:6,自引:0,他引:6
目的探讨进展性脑梗死的影像学特点及与脑动脉狭窄之间的相关性。方法选择我院29例进展性脑梗死患者并与同期收治的31例完全性脑梗死患者比较,所有患者均行头颅MRI (或头颅CT)及脑血管造影检查(DSA检查),分析进展性脑梗死的影像特点及其与脑动脉狭窄的相关性。结果进展性脑梗死组分水岭脑硬死或侧脑室体旁梗死发生率72.4%(21/29)及脑动脉狭窄发生率75.86%(22/29)均明显高于完全性脑梗死组22.6%(7/31),35.48%(11/31)。进展性脑梗死组中重度狭窄发生率为55.17%(16/29),高于完全性脑硬死组的12.90%(4/31)。溃疡性斑块发生率在进展性脑梗死组48.28%(14/29)高于完全性脑梗死组16.13%(5/31)。结论中重度脑动脉狭窄及溃疡是进展性卒中的重要危险因素,应早期检查及处理脑动态狭窄以防止病情进展。 相似文献
87.
目的报告2002年4月至2004年12月67例冠状动脉旁路移植手术(CABG).方法男性58例,女性9例,年龄41~76岁,平均58.5岁.合并二尖瓣病变同期手术3例,3支血管病变39例,2支血管病变28例.采取体外循环下手术(on-pump-CABG)和非体外循环下手术(off-pump-CABG)两种方式,各有其适应指征.结果全组死亡1例,其余治愈出院,随诊1~18个月,心绞痛消失,疗效满意.结论冠状动脉旁路移植手术安全,有很好的发展前景. 相似文献
88.
目的 应用超声多普勒技术测量正常婴儿肺动脉主干及左右肺动脉血流速度,并初步探讨其可能的机理.方法 使用GE Vivid7超声诊断仪检查60例正常新生儿,分别检测1周、1个月、6个月及1年时主动脉内径AOD;肺动脉主干内径MPA及血流速度Pv,左、右肺动脉内径LPA、RPA及血流速度LPv、RPv,并计算LPA RPA/AO.结果 1周时左、右肺动脉速度高于肺动脉主干速度,且以右肺动脉明显,1周后左、右肺动脉血流速度逐渐减慢,1年后均基本低于肺动脉主干内血流速度,肺动脉主干血流速度及LPA RPA/AO比例在1周、1个月、6个月及1年组差异无统计学意义.结论 正常新生儿左、右肺动脉血流速度较高,随生长、发育肺动脉血流速度逐渐降低直至正常. 相似文献
89.
经桡动脉行冠状动脉造影术的安全性观察 总被引:3,自引:0,他引:3
目的探讨经桡动脉行冠状动脉(冠脉)造影术的特点及安全性。方法200例患者接受经桡动脉径路行冠脉造影术。结果196例成功,4例失败,其中3例桡动脉迂曲畸形导丝不能通过,1例为锁骨下动脉闭塞。所有患者无严重的并发症出现。结论桡动脉径路行冠状动脉造影具有止血容易,患者卧床时间短和并发症少的优点,是一种安全、有效的介入途径。 相似文献
90.
目的:研究异丙酚和异氟醚对非体外循环搭桥术患者围术期炎性与抗炎性细胞因子平衡的影响。方法:择期非体外循环搭桥患者50例,随机分为2组。异丙酚组微量泵输入剂量为4~6mg·kg-·1h-1,异氟醚组吸入浓度为1%~1.5%。检测诱导前、打开心包、旁路血管开放30min,术后2h、24h血清白细胞介素6(IL-6)、白细胞介素10(IL-10)和肿瘤坏死因子α(TNF-α)的浓度。结果:2组患者旁路血管开放后IL-6浓度较术前升高(P<0.01),术后2h达高峰;术后2h异氟醚组高于异丙酚组(P<0.05)。IL-10浓度变化趋势与IL-6相似,旁路血管开放后、术后2h和24h异丙酚组高于异氟醚组(P<0.05)。2组患者TNF-α水平均无显著变化。结论:异丙酚麻醉促进IL-10的产生,抑制IL-6的产生,控制术中应激反应异丙酚优于异氟醚。 相似文献