全文获取类型
收费全文 | 27699篇 |
免费 | 2049篇 |
国内免费 | 540篇 |
专业分类
耳鼻咽喉 | 187篇 |
儿科学 | 1112篇 |
妇产科学 | 762篇 |
基础医学 | 2165篇 |
口腔科学 | 310篇 |
临床医学 | 3134篇 |
内科学 | 4946篇 |
皮肤病学 | 237篇 |
神经病学 | 2773篇 |
特种医学 | 761篇 |
外国民族医学 | 1篇 |
外科学 | 2465篇 |
综合类 | 3729篇 |
现状与发展 | 1篇 |
一般理论 | 6篇 |
预防医学 | 3128篇 |
眼科学 | 240篇 |
药学 | 2068篇 |
15篇 | |
中国医学 | 387篇 |
肿瘤学 | 1861篇 |
出版年
2024年 | 33篇 |
2023年 | 562篇 |
2022年 | 815篇 |
2021年 | 1325篇 |
2020年 | 1285篇 |
2019年 | 1098篇 |
2018年 | 1104篇 |
2017年 | 994篇 |
2016年 | 1008篇 |
2015年 | 996篇 |
2014年 | 2122篇 |
2013年 | 2111篇 |
2012年 | 1666篇 |
2011年 | 1766篇 |
2010年 | 1370篇 |
2009年 | 1314篇 |
2008年 | 1340篇 |
2007年 | 1143篇 |
2006年 | 1041篇 |
2005年 | 832篇 |
2004年 | 710篇 |
2003年 | 640篇 |
2002年 | 567篇 |
2001年 | 478篇 |
2000年 | 438篇 |
1999年 | 390篇 |
1998年 | 355篇 |
1997年 | 313篇 |
1996年 | 282篇 |
1995年 | 275篇 |
1994年 | 237篇 |
1993年 | 195篇 |
1992年 | 205篇 |
1991年 | 169篇 |
1990年 | 149篇 |
1989年 | 139篇 |
1988年 | 130篇 |
1987年 | 95篇 |
1986年 | 72篇 |
1985年 | 104篇 |
1984年 | 87篇 |
1983年 | 57篇 |
1982年 | 48篇 |
1981年 | 30篇 |
1980年 | 29篇 |
1979年 | 39篇 |
1978年 | 27篇 |
1977年 | 21篇 |
1976年 | 19篇 |
1973年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
141.
Anna Gasinska Jan Skolyszewski Tadeusz Popiela Piotr Richter Zbigniew Darasz Krystyna Nowak Joanna Niemiec Beata Biesaga Agnieszka Adamczyk Krzysztof Bucki Krzysztof Malecki Marian Reinfuss Teresa Kowalska 《Journal of gastrointestinal surgery》2007,11(4):520-528
Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal
cancer response to preoperative radiotherapy (RT).
Methods and material Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I),
or to short RT and 4–5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before
RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37°C, and the BrdUrdLI was calculated as
a percentage of BrdUrd-labeled cells.
Results Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before
RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically
significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical
and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios
were calculated separately for fast (BrdUrd LI > 8.5%) and slowly (BrdUrd LI ≤ 8.5%) proliferating tumors and correlated with
overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation
was observed only in slowly proliferating tumors.
Conclusions Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI
was correlated to inhibition of proliferation in responsive tumors.
The paper was presented at ECCO 13, October 30 to November 03, 2005 in Paris, France 相似文献
142.
143.
肥厚型心肌病预后评估的研究进展 总被引:1,自引:0,他引:1
肥厚型心肌病是最常见的遗传性心脏病,其临床表现及预后极富多样性。该病患者的不良转归主要有:猝死、心力衰竭以及心房颤动所致的栓塞事件等。现就影响肥厚型心肌病预后的因素作一综述。 相似文献
144.
David M. Dickinson Dawn M. Dykstra Gregory N. Levine Shiqian Li James C. Welch Randall L. Webb 《American journal of transplantation》2005,5(4P2):850-861
The process of collecting and analyzing transplant data is complex. Familiarity with how these data are collected is crucial to a thorough understanding of the information. This article focuses on available OPTN-SRTR data and the continuing evolution of data collection mechanisms; how that data collection system is improving the data quality and reducing the data collection burden; how additional ascertainment of outcomes both completes and validates existing data; and caveats that remain for researchers. This year's article focuses further on research considerations related to cohort choice, timing of data submission, and potential biases in follow-up data. Ongoing improvements in data collection timeliness and scope are covered. The impact of extra ascertainment of outcomes, particularly for post-transplant kidney graft failure from Medicare data, are also examined. A section on graft failure reporting among different sources traces the steps by which the SRTR reconciles different data sources in its analyses. It is important that those reading and conducting transplant research understand the origin, structure, and scope of the available data. All of these issues should be carefully considered when choosing cohorts and data sources for analysis. 相似文献
145.
Chen Xinshan Zhang Yigu Rao Guangxun Huang Guangzhao 《Frontiers of Medicine in China》2007,1(3):338-342
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a kind of primary myocardial disease characterized by the regional
or global replacement of right ventricular myocardium by fatty and fibrolipomatous tissues. The ARVC, usually presenting with
different clinical manifestations and pathological changes, were mainly seen in young men and is one of the main causes of
sudden death in the young. Here two autopsied cases of Chinese men aged 30 and 23 years old who appeared healthy but died
suddenly while at work are reported respectively. One of the victims had extensive and severe pathological changes in his
heart involving the left ventricular wall as well as the ventricular septum and the right atrium. Not only was there a global
fatty and fibrolipomatous tissue replacement of the right ventricular myocardia, but also mild sarcoplasmic coagulation in
the myocardium and focal lymphocytic infiltration in the myocardial interstitium of the right ventricular wall. In addition,
slight atherosclerosis of the coronary artery and intimal thickening of the sino-atrial node were observed. It is believed
that there are no marked differences in the pathological changes of ARVC between Chinese patients and patients from western
countries. The etiology and pathogenesis of ARVC could not be explained by a single cause or factor and they are probably
related to various congenital and acquired causes or factors. 相似文献
146.
187例肾移植受者死亡原因分析 总被引:13,自引:1,他引:12
目的分析肾移植受者的死亡原因。方法回顾性分析1978年至2003年期间进行同种肾移植的1400例受者资料。对肾移植后受者的死亡率、死亡原因和时间进行分析。结果1400例肾移植受者中,共死亡187例,死亡率为13.36%。187例受者的死亡原因依次为感染、心脑血管疾病和肝功能衰竭;所占比率分别为37.97%、31.56%和14.97%。死亡的受者中,移植肾有功能的87例,占46.5%。结论感染、心脑血管疾病及肝功能衰竭是肾移植后受者死亡的主要原因。将近一半的受者死亡时移植肾有功能。 相似文献
147.
颈椎脊髓损伤早期死亡原因分析 总被引:1,自引:0,他引:1
目的探讨颈椎脊髓损伤早期死亡原因。方法回顾性分析1993年1月~2005年12月63例颈椎脊髓损伤早期死亡病例的一般状况、受伤原因、受伤至入院时间、脊柱损伤节段、脊髓损伤严重程度、合并伤、颈椎脊髓损伤影像学表现、治疗方法、过程及结果,总结其早期死亡的原因。结果本组49例因呼吸衰竭死亡,8例因多脏器功能衰竭死亡,2例因癫痫发作导致急性呼吸、循环衰竭死亡,2例因多发伤导致肺部感染及感染性休克死亡,2例因上消化道大出血导致出血性休克死亡。结论呼吸衰竭为颈椎脊髓损伤早期死亡的首要原因,其与脊髓损伤节段及损伤程度密切相关。 相似文献
148.
149.
目的观察刺五加注射液及抗凝剂(潘生丁、肠溶阿斯匹林)对糖尿病足早期干预治疗的影响。方法将符合1999年WHO诊断标准的100例糖尿病合并早期足病变的患者分为两组:干预治疗组50例,对照组50例。在控制血糖、血压、糖尿病教育的基础上,干预组予以静滴刺五加注射液及口服抗凝剂(潘生丁、肠溶阿斯匹林)治疗,对照组为口服VitB1、VitB6、复方丹参片治疗。观察治疗前后两组患者足背动脉搏动、皮肤颜色、温度,痛、温、触觉等相关指征,血糖、HbA1c、血TG、TC、HDL-C,及血流变学、眼底病变、心脑血管事件发生率等。结果干预组糖尿病足病变治疗好转率高,恶化发展率低,心脑血管事件发生率少。血脂、血流变学、下肢血管多普勒彩超及眼底病变等好转改善明显,与对照组比较差异有统计学意义(P<0.05或P<0.01)。结论刺五加注射液及抗凝剂(潘生丁、肠溶阿斯匹林)对糖尿病足病变的早期干预治疗疗效显著,有重要的临床意义。 相似文献
150.
Fragmentation is frequently observed in animal and human embryosobtained via in-vitro fertilization (IVF), and is known to beassociated with decreased pregnancy rates and poor survivalfollowing cryopreservation. We postulate that embryo fragmentationis a consequence of activated programmed cell death (PCD) andsubsequent apoptosis and discuss evidence of morphological,histological and biochemical features compatible with the occurrenceof PCD in preimplantation embryos. If PCD is an underlying causeof the high incidence of the fragmentation seen in human pre-embryos,it remains to be determined whether this is reflective of thenatural incidence of lethal chromo somes in the human populationor due to the IVF procedure and culture conditions. 相似文献