全文获取类型
收费全文 | 3644篇 |
免费 | 266篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 37篇 |
妇产科学 | 65篇 |
基础医学 | 643篇 |
口腔科学 | 132篇 |
临床医学 | 313篇 |
内科学 | 400篇 |
皮肤病学 | 115篇 |
神经病学 | 723篇 |
特种医学 | 114篇 |
外科学 | 390篇 |
综合类 | 226篇 |
现状与发展 | 2篇 |
预防医学 | 129篇 |
眼科学 | 191篇 |
药学 | 237篇 |
中国医学 | 83篇 |
肿瘤学 | 172篇 |
出版年
2024年 | 8篇 |
2023年 | 79篇 |
2022年 | 95篇 |
2021年 | 178篇 |
2020年 | 155篇 |
2019年 | 148篇 |
2018年 | 143篇 |
2017年 | 128篇 |
2016年 | 117篇 |
2015年 | 118篇 |
2014年 | 240篇 |
2013年 | 232篇 |
2012年 | 195篇 |
2011年 | 226篇 |
2010年 | 206篇 |
2009年 | 175篇 |
2008年 | 184篇 |
2007年 | 186篇 |
2006年 | 160篇 |
2005年 | 128篇 |
2004年 | 104篇 |
2003年 | 110篇 |
2002年 | 82篇 |
2001年 | 73篇 |
2000年 | 74篇 |
1999年 | 51篇 |
1998年 | 55篇 |
1997年 | 54篇 |
1996年 | 41篇 |
1995年 | 28篇 |
1994年 | 21篇 |
1993年 | 14篇 |
1992年 | 15篇 |
1991年 | 14篇 |
1990年 | 17篇 |
1989年 | 13篇 |
1988年 | 21篇 |
1987年 | 14篇 |
1986年 | 8篇 |
1985年 | 21篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1982年 | 11篇 |
1981年 | 9篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1975年 | 2篇 |
1973年 | 2篇 |
排序方式: 共有3987条查询结果,搜索用时 15 毫秒
41.
N. A. Ebraheim J. Lu Y. Hao A. Biyani R. A. Yeasting 《Surgical and radiologic anatomy : SRA》1998,20(4):259-262
The anterior tibial artery (ATA) is at risk of injury during high tibial osteotomy, Ilizarov wire placement, pin placement in external fixation, or proximal locking screw insertion, as the artery is not visualized intraoperatively. The ATA is anchored to the oval foramen of the interosseous membrane on the proximal tibia by the deep fascia and recurrent genicular vascular branches. Segment 1 (from the bifurcation of the popliteal artery to the level of the interosseous foramen) and the proximal part of segment 2 (from the interosseous foramen to the level where the artery crosses the anterior border of the tibia) may be damaged when pin, wire or screw placement is directed posterolaterally at that level. Distally, a straight mediolateral pin or Ilizarov wires may lacerate the artery. Segment 2 of the ATA descends against the interosseous membrane in its proximal part, which is projected on the posterior third of the tibia relative to the sagittal plane; in its middle part, it runs close to the lateral cortex of the tibia, it is projected on the middle third of the tibia; in its distal part it runs gradually towards the anterior third of the tibia and contacts with the anterior third of the tibial cortical surface. This information may help reduce risk of injury to the ATA during high tibial osteotomy, external fixation and pin placement or insertion of locking screws. 相似文献
42.
脑缺血大鼠大脑皮层和室管膜下区细胞增殖及巢蛋白表达 总被引:1,自引:0,他引:1
目的:探讨脑缺血损伤对大鼠脑皮层和室管膜下区细胞增殖及巢蛋白表达的影响。方法:采用大鼠局灶性脑缺血模型,观察大脑皮层和室管膜下区的细胞增殖及巢蛋白阳性细胞表达。结果:脑缺血大鼠室管膜下区细胞增殖明显增加,巢蛋白阳性细胞表达也显著增加;大脑皮层细胞增殖无明显改变,但巢蛋白阳性细胞表达则明显增加。结论:脑缺血损伤可激活室管膜下区与大脑皮层神经干细胞。提示脑缺血大鼠室管膜下区与大脑皮层的神经干细胞可能参与脑缺血损伤的神经修复过程。 相似文献
43.
Zandvoort A Lodewijk ME Klok PA Breukels MA Rijkers GT Timens W 《Clinical and experimental immunology》2003,131(1):8-16
Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment. The splenic marginal zone is essential in the initiation of an immune response to encapsulated bacteria. In this study, we analysed the effects of three different cytostatic agents on humoral immune responses. We found a reduced, but detectable immune response capacity at two days after treatment although the marginal zone B cell population is severely reduced at this time point. Twenty-four days after cessation of treatment, the immune response capacity was largely restored although lymphoid compartments were still not completely restored at that time point. Apparently, the presence of only few marginal zone B cells is sufficient to evoke a rise in antibody titres and although antibody titre increases are low, even small rises are most likely clinically relevant. 相似文献
44.
利用磁共振成像实现肿瘤热疗中实时无创测温的方法 总被引:4,自引:0,他引:4
肿瘤热疗特别是高强度聚焦超声(HIFU)技术,已成为一种重要且非常具有前景的肿瘤治疗方法,温度是直接决定热疗效果的重要参数,实时准确的进行深部无创测温是目前制约肿瘤热疗进一步发展的一项关键技术。近来利用磁共振成像(MRI)进行无创测温,正受到越来越多的研究者的重视。本文简述了MRI无创测温的三种方法,比较了不同测温原理的特点和适用条件,报道了已有研究发展状况,并介绍了尚待解决的问题。 相似文献
45.
损毁单侧黑质-纹状体通路的大鼠SVZ、纹状体和黑质神经前体细胞的变化 总被引:1,自引:0,他引:1
研究成年大鼠脑室下区 (SVZ)神经前体细胞 (neural precursors)在黑质 -纹状体通路损伤后的反应 ,本研究用 6-羟多巴胺单侧纹状体注射以损毁黑质 -纹状体通路 ,损毁 10 d后腹腔注射 Brd U ,连续 4d,每日两次 ;在 SVZ、纹状体和黑质部位用免疫组化方法检测 Brd U、nestin以及 GFAP阳性细胞。结果显示 :(1) 6-羟多巴胺损毁黑质 -纹状体通路后 ,伤侧 SVZ的 Brd U阳性细胞数明显增多 ,并成簇分布 ;nestin和 GFAP阳性细胞数也增多 ,但以 GF AP阳性细胞增多明显 ;(2 )伤侧纹状体可见大量 Br-d U、GFAP以及少量 nestin阳性细胞分布 ,而健侧只有少量 GFAP阳性细胞 ;(3 )伤侧可见 Brd U阳性细胞在 SVZ和纹状体之间呈条带样分布 ;(4 )伤侧黑质除酪氨酸羟化酶阳性神经元减少外 ,未见 Brd U、GFAP和 nestin阳性细胞表达。上述结果表明 ,6-羟多巴胺损毁黑质 -纹状体通路后 ,SVZ神经前体细胞活动增强 ,有向纹状体迁移的趋势。 相似文献
46.
Maria Carmina Castiello Marita Bosticardo Nicolò Sacchetti Enrica Calzoni Elena Fontana Yasuhiro Yamazaki Elena Draghici Cristina Corsino Ileana Bortolomai Lucia Sereni Hsin-Hui Yu Paolo Uva Rahul Palchaudhuri David T. Scadden Anna Villa Luigi D. Notarangelo 《The Journal of allergy and clinical immunology》2021,147(1):309-320.e6
47.
《Journal of the American Medical Directors Association》2022,23(1):60-65
ObjectiveBoth high-intensity interval training (HIIT) and resistance exercises (R) are used in cardiac rehabilitation in patients with coronary artery disease (CAD). However, the combined effect of an HIIT + R exercise program in older adults with CAD is not well investigated. The study's purpose was to assess the changes in anthropometric parameters, physical activity, functional capacity, physiological parameters, and quality of life (QoL) in this population following a combined HIIT + R program.DesignThe study was a 2-group (n = 45 each) randomized controlled single-blinded trial.Setting and ParticipantsThe study was done at a treatment clinic of a tertiary hospital. The mean age of participants was 69.23 ± 4.9 years. The HIIT + R group performed 8 sessions (1/wk) of HIIT + R training. The 30 minutes of the active exercise phase consisted of ten 3-minute bouts. Each bout comprised of 1 minute of high-intensity treadmill walking at 85% to 90% maximum heart rate (MHR), followed by a low-intensity walking at 60%-70% MHR, followed by low-to moderate-intensity resistance training. The Usual Care group underwent conventional medical treatment.MeasuresAnthropometric measurements [weight, body mass index (BMI), waist circumference, body fat percentage, lean body mass], physical activity (International Physical Activity Questionnaire), functional capacity (Incremental Shuttle Walking Test), physiologic measurements (blood pressure, heart rate), and QoL (36-Item Short Form Health Survey) were measured pre- and postintervention.ResultsSignificant group and time interaction were found for the participants in the HIIT + R Group for BMI (P = .001), body fat percentage (P = .001), waist circumference (P < .001), physical activity (P < .001), functional capacity (P < .001), and QoL (P = .001) compared with the UC Group. Significant improvement in systolic blood pressure (P = .001) was seen in the HIIT + R group.Conclusions and ImplicationsA combined HIIT + R training protocol in older adults with CAD can be useful in producing desired health outcomes. Further evaluation of longer duration exercise programs with more frequent dosing needs to be evaluated for their benefits and sustainability. 相似文献
48.
Yuta Yamamoto Yusuke Miyagawa Masato Kitazawa Hirokazu Tanaka Masatsugu Kuroiwa Nao Hondo Makoto Koyama Satoshi Nakamura Shigeo Tokumaru Futoshi Muranaka Yuji Soejima 《Asian journal of surgery / Asian Surgical Association》2021,44(1):292-297
Background/Objective: The feces sign has been reported as a possible predictive factor for non-operative treatment of small bowel obstruction. However, its relationship with prognosis of non-emergency adhesive small bowel obstruction remains unclear. This study aimed to clarify the relationship between the feces sign and prognosis of non-emergency adhesive small bowel obstruction.MethodsNinety-two patients with non-emergency adhesive small bowel obstruction with the transitional zone visible on computed tomography were included. Patients were categorized into two groups: feces sign positive (n = 40) and negative (n = 52). Clinical features and prognosis were compared between the two groups. Cox proportional hazards regression models incorporating the feces sign were used to analyze odds of diet resumption and discharge.ResultsPatients with feces sign were younger (p = 0.015), had a higher body mass index (p = 0.027), and a lower white blood cell count (p = 0.019) on admission. More patients with feces sign were successfully treated with fasting and/or nasogastric tube placement (p < 0.001), and no patient with feces sign suffered from recurrent obstruction after diet resumption. Kaplan–Meier analysis showed that patients with feces sign took less time for diet resumption (p = 0.007) and discharge (p = 0.004) than those without it. Using Cox proportional hazards regression model, the feces sign was reported as an independent predictor of diet resumption (odds ratio 1.685, p = 0.018) and discharge (odds ratio 1.861, p = 0.007).ConclusionsThe feces sign is associated with improved odds for diet resumption and discharge. 相似文献
49.
本研究通过结扎家免在位心脏冠状动脉左室支造成急性心肌缺血。结果显示不仅缺血区心肌有明显的电生理变化,在非缺血区亦有电生理变化,后者主要表现为广泛的非缺血区域有效不应期(ERP)呈普遍轻度延长,与缺血边缘带共同形成一个不应期离散和跃变带。这种电生理紊乱易于诱发折反性心律失常的产生。升高循环血中几条酚胺浓度并不能模拟非缺血区的电生理变化。刺激连走神经外周瑞虽可使自然心律情况下的ERP延长,但却不能使固定心律情况下的ERP延长。提示非缺血区的电生理学变化并非由于心肌缺血时交感或迷走神经张力增高所致,而可能有其它原因。 相似文献
50.