全文获取类型
收费全文 | 30477篇 |
免费 | 1811篇 |
国内免费 | 105篇 |
专业分类
耳鼻咽喉 | 278篇 |
儿科学 | 746篇 |
妇产科学 | 658篇 |
基础医学 | 3800篇 |
口腔科学 | 923篇 |
临床医学 | 3182篇 |
内科学 | 6055篇 |
皮肤病学 | 397篇 |
神经病学 | 2927篇 |
特种医学 | 1210篇 |
外科学 | 3437篇 |
综合类 | 311篇 |
一般理论 | 31篇 |
预防医学 | 3016篇 |
眼科学 | 746篇 |
药学 | 2491篇 |
中国医学 | 43篇 |
肿瘤学 | 2142篇 |
出版年
2023年 | 109篇 |
2022年 | 163篇 |
2021年 | 391篇 |
2020年 | 267篇 |
2019年 | 450篇 |
2018年 | 510篇 |
2017年 | 411篇 |
2016年 | 433篇 |
2015年 | 525篇 |
2014年 | 821篇 |
2013年 | 1360篇 |
2012年 | 1965篇 |
2011年 | 2105篇 |
2010年 | 1157篇 |
2009年 | 1183篇 |
2008年 | 2040篇 |
2007年 | 2267篇 |
2006年 | 2263篇 |
2005年 | 2168篇 |
2004年 | 2141篇 |
2003年 | 2026篇 |
2002年 | 1985篇 |
2001年 | 287篇 |
2000年 | 185篇 |
1999年 | 307篇 |
1998年 | 443篇 |
1997年 | 365篇 |
1996年 | 342篇 |
1995年 | 296篇 |
1994年 | 279篇 |
1993年 | 263篇 |
1992年 | 153篇 |
1991年 | 176篇 |
1990年 | 143篇 |
1989年 | 136篇 |
1988年 | 126篇 |
1987年 | 126篇 |
1986年 | 107篇 |
1985年 | 156篇 |
1984年 | 211篇 |
1983年 | 158篇 |
1982年 | 241篇 |
1981年 | 244篇 |
1980年 | 232篇 |
1979年 | 108篇 |
1978年 | 105篇 |
1977年 | 105篇 |
1976年 | 81篇 |
1975年 | 70篇 |
1974年 | 63篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
Otavio A C Clark Gary H Lyman Aldemar A Castro Luciana G O Clark Benjamin Djulbegovic 《Journal of clinical oncology》2005,23(18):4198-4214
PURPOSE: Current treatment for febrile neutropenia (FN) includes hospitalization for evaluation, empiric broad-spectrum antibiotics, and other supportive care. Clinical trials have reported conflicting results when studying whether the colony-stimulating factors (CSFs) improve outcomes in patients with FN. This Cochrane Collaboration review was undertaken to further evaluate the safety and efficacy of the CSFs in patients with FN. METHODS: An exhaustive literature search was undertaken including major electronic databases (CANCERLIT, EMBASE, LILACS, MEDLINE, SCI, and the Cochrane Controlled Trials Register). All randomized controlled trials that compare CSFs plus antibiotics versus antibiotics alone for the treatment of established FN in adults and children were sought. A meta-analysis of the selected studies was performed. RESULTS: More than 8,000 references were screened, with 13 studies meeting eligibility criteria for inclusion. The overall mortality was not influenced significantly by the use of CSF (odds ratio [OR] = 0.68; 95% CI, 0.43 to 1.08; P = .1). A marginally significant result was obtained for the use of CSF in reducing infection-related mortality (OR = 0.51; 95% CI, 0.26 to 1.00; P = .05). Patients treated with CSFs had a shorter length of hospitalization (hazard ratio [HR] = 0.63; 95% CI, 0.49 to 0.82; P = .0006) and a shorter time to neutrophil recovery (HR = 0.32; 95% CI, 0.23 to 0.46; P < .00001). CONCLUSION: The use of the CSFs in patients with established FN caused by cancer chemotherapy reduces the amount of time spent in hospital and the neutrophil recovery period. The possible influence of the CSFs on infection-related mortality requires further investigation. 相似文献
35.
Nicholas L. Shortt Gary F. Keenan Andrew Y. Muir Prof. Dr. A. Hamish R. W. Simpson 《Operative Orthopadie und Traumatologie》2006,18(4):364-376
OBJECTIVE: Avoidance of potential iatrogenic nerve injury during insertion of Ilizarov fine wires into areas of high anatomic risk by using a modified nerve stimulation technique. INDICATIONS: Application of the Ilizarov ring fixator to areas of high anatomic hazard, in situations where anatomic topography may be distorted by previous surgery, trauma, or congenital anomalies. CONTRAINDICATIONS: Use of systemic muscle relaxants. Caution in patient with cardiac pacemaker. SURGICAL TECHNIQUE: Preliminary experiments showed that a standard nerve-stimulating device can deliver a negatively charged, monophasic square pulse of current through Ilizarov wires. During the application of an Ilizarov frame to potentially hazardous anatomic regions, providing no systemic muscle relaxants are used, a voltage field sufficient to cause nerves in close proximity to the Ilizarov wire to depolarize is produced. Identification of a distal muscle twitch provoked by the stimulation may indicate a potential for iatrogenic nerve injury. RESULTS: Results show that with the nerve stimulator set at 2.5 mA (pulsed at a frequency of 2 Hz), peripheral nerves are stimulated if they lie within 5 mm of the wires. Should a distal muscle twitch occur, wires should be repositioned so that equivalent stimulation produces no twitch. The technique was used during Ilizarov frame application in ten patients, with only a single occurrence of distal muscle twitches in a lower-leg frame. Following repositioning of the Ilizarov wire in this case, no further twitches were observed, indicating that no Ilizarov wire was inserted close to peripheral nerves. No neurologic impairment was present postoperatively. 相似文献
36.
37.
38.
Stephen Sawada Otto Muzik Rob S. B. Beanlands Edwin Wolfe Gary D. Hutchins Markus Schwaiger 《Journal of nuclear cardiology》1995,2(5):413-422
Background
Experimental studies have shown that positron emission tomography (PET) with 13N-labeled ammonia provides accurate quantification of regional myocardial blood flow (MBF) under rest and stress conditions. To establish the clinical utility of this method, the interobserver variability and the temporal variability of serial measurements of blood flow and coronary flow reserve (CFR) must be known. This study investigated the interobserver and temporal reproducibility of 13N-labeled PET for measurement of MBF and CFR. 相似文献39.
应用双光子及单光子吸收测定技术,检测了92名出生3d内的新生儿骨矿质含量,其中巨大儿30名,正常体重儿32名,低出生体重儿30名,其孕龄分别是40.1±0.7、39.1±1.5和37.4±1.2孕周。结果表明,巨大儿、正常体重儿、低出生体重儿的全身骨矿质含量分别是101.6±28.8、85.2±19.8、59.9±27.2g/cm2,巨大儿骨矿质含量最高,正常体重儿次之,低出生体重儿最低,差异有显著性(P<0.01)。颅骨、肱骨、股骨的骨矿质含量与全身的骨矿质含量有高度的相关性,相关系数分别是0.943、0.879和0.745(P<0.01)。全身的骨矿质含量与出生体重、孕龄及头围有高度相关性,相关系数分别是0.755、0.596和0.556(P<0.01)。提示颅骨、肱骨及股骨的任一部位均可代表全身的骨矿质含量,肱骨是确定全身骨矿质含量较好的部位,新生儿骨矿质含量受出生体重、孕龄及头围的影响较大。 相似文献
40.
Roberto Civitelli M.D. Eturo Ogata Louis V. Avioli Gary Stein Samuel Edelstein John A. Eisman Yasuho Nishii Hajime Orimo Jane Lian Takuo Fujita Yasufumi Hayashi Shigeaki Kato Tadashi Kobayashi Hirotoshi Morii Rikushi Morita Toshitaka Nakamura Yoshiki Seino Masataka Shiraki Tatsuo Suda Naoyuki Takahashi Hideaki Takahashi Tastuhiko Tanisawa Akifumi Tokita 《Calcified tissue international》1995,57(6):409-414