全文获取类型
收费全文 | 11525篇 |
免费 | 831篇 |
国内免费 | 299篇 |
专业分类
耳鼻咽喉 | 565篇 |
儿科学 | 147篇 |
妇产科学 | 89篇 |
基础医学 | 899篇 |
口腔科学 | 482篇 |
临床医学 | 1071篇 |
内科学 | 769篇 |
皮肤病学 | 67篇 |
神经病学 | 1508篇 |
特种医学 | 299篇 |
外科学 | 3333篇 |
综合类 | 1473篇 |
预防医学 | 587篇 |
眼科学 | 159篇 |
药学 | 653篇 |
9篇 | |
中国医学 | 184篇 |
肿瘤学 | 361篇 |
出版年
2024年 | 32篇 |
2023年 | 221篇 |
2022年 | 424篇 |
2021年 | 563篇 |
2020年 | 599篇 |
2019年 | 465篇 |
2018年 | 439篇 |
2017年 | 506篇 |
2016年 | 493篇 |
2015年 | 465篇 |
2014年 | 901篇 |
2013年 | 925篇 |
2012年 | 659篇 |
2011年 | 713篇 |
2010年 | 622篇 |
2009年 | 648篇 |
2008年 | 535篇 |
2007年 | 575篇 |
2006年 | 460篇 |
2005年 | 418篇 |
2004年 | 349篇 |
2003年 | 271篇 |
2002年 | 210篇 |
2001年 | 174篇 |
2000年 | 124篇 |
1999年 | 104篇 |
1998年 | 102篇 |
1997年 | 90篇 |
1996年 | 78篇 |
1995年 | 57篇 |
1994年 | 40篇 |
1993年 | 40篇 |
1992年 | 41篇 |
1991年 | 38篇 |
1990年 | 27篇 |
1989年 | 33篇 |
1988年 | 33篇 |
1987年 | 17篇 |
1986年 | 19篇 |
1985年 | 29篇 |
1984年 | 23篇 |
1983年 | 18篇 |
1982年 | 17篇 |
1981年 | 12篇 |
1980年 | 10篇 |
1979年 | 7篇 |
1978年 | 9篇 |
1977年 | 4篇 |
1976年 | 5篇 |
1975年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Maeda S Suzuki S Moriya T Suzuki T Chida M Suda H Sakuma H Kondo T Sasano H 《Pathology international》2001,51(8):649-653
We report a case of isolated unilateral absence of a pulmonary artery. The first clinical symptom that was manifested in the patient was recurrent hemoptysis, and subsequent angiography revealed that the main pulmonary artery was absent in the right lung, which was being fed only from the systemic circulation. Right pneumonectomy was performed, and neither the main pulmonary artery nor its remnant was detected in the resected right lung. Histologically, there were many muscular vessels in the resected lung, with intimal proliferation, or with plexiform-like lesions. The alveolar septum was moderately thickened and alveolar capillary vessels were dilated. We examined the alveolar capillary endothelial cells of the resected lung for immunoreactivity to thrombomodulin (TM) and von Willebrand factor (vWF). The endothelial cells were negative for TM and positive for vWF, while in the normal lung control group, these cells were positive for TM and negative for vWF. We considered that the hemodynamics of the systemic circulation in the resected lung caused the alteration of immunohistochemical characteristics in alveolar capillary endothelial cells. 相似文献
122.
Chekhonin VP Lebedev SV Ryabukhin IA Petrov SV Gurina OI Dmitrieva TB Volkov AI Kashparov IA Skoblov YS 《Bulletin of experimental biology and medicine》2004,138(4):343-347
Preparations of I125-labeled monoclonal antibodies against neurospecific enolase and mouse plasma IgG1 were injected intravenously to rats immediately after unilateral occlusion of the middle cerebral artery. Radioactivity of I125-labeled monoclonal antibodies against neurospecific enolase in the brain tissue progressively increased, reached a maximum by the 48th hour, and remained practically unchanged after 72 h. At the same time radioactivity of labeled IgG1 in the brain tissue and radioactivity of both preparations in the blood, liver, spleen, kidneys, heart, and lungs decreased over 72 h. Selective accumulation of I125-labeled monoclonal antibodies against neurospecific enolase was less significant in the brain tissue of the contralateral hemisphere and cerebellum not exposed to ischemia.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 10, pp. 388–392, October, 2004 相似文献
123.
逆行带锁髓内钉治疗股骨远端骨折的应用解剖 总被引:6,自引:0,他引:6
目的:为带锁髓内钉治疗股骨远端骨折提供形态学基础。方法:①选用30例成人干燥股骨测量股骨内外侧髁、内外上髁、髁间窝有关数据进行统计分析。②20侧下肢标本解剖观测膝降动脉及隐神经髌下支的分支、分支等及两者的关系。结果:髁间窝呈U型占35%,V型占65%,此窝最宽处横径:左侧(1.98±0.36)cm, 右侧(2.06±0.29) cm;内侧髁后关节面宽,左侧(2.21±0.23) cm,右侧(2.34±0.29) cm;内、外上髁的距离,左侧(7.30±0.60)cm,右侧(7.43±0.57)cm。膝降动脉髌下支和隐神经髌下支呈紧密的伴行关系。隐神经在缝匠肌中下1/3交界点穿出,有上、下两支分布到膝关节前外侧皮肤。结论:术中注意这些解剖位置特点,避免损伤神经和血管,减少手术出血,防止并发症。 相似文献
124.
Chiao-Hsi Chiang Ronald D. Schoenwald 《Journal of pharmacokinetics and pharmacodynamics》1986,14(2):175-211
A single topical instillation of clonidine-3H HCl solution (0.2%) was administered to the rabbit eye (30 μl) in order to study the drug's ocular pharmacokinetics. Seven different tissues and plasma were excised and assayed for drug over 180min. By 45–60 min pseudoequilibrium is reached for the cornea, iris/ciliary body, and aqueous humor. Thereafter, drug levels in these tissues decline in parallel. The data are fit separately to a physiological model and a classical diffusion model for which seven ocular tissue compartments and a plasma reservoir are constructed for each model. Clearance terms and distribution equilibrium coefficients are determined from the tissue level data and used as parameters in fitting the mass balance differential equations representing the physiological model. The model parameters can also be fit to a 0.4% single dose. In a separate experiment, a topical infusion technique was designed to provide a constant rate input to the cornea until an apparent steady state was reached in aqueous humor at 55 min. Aqueous humor levels were assayed for clonidine over the infusion and postinfusion periods. The physiological model parameters are fit to the topical infusion data and show good agreement between the predicted and experimental data. The classical model is too complex to fit the data to integrated exponential equations primarily because the method of residuals is inadequate in determining a sufficient set of initial estimates. This is overcome by dividing the eight-compartment model into seven fragmental models, each representing one to five compartments. A stepwise procedure is developed in which initial estimates are obtained for each separate fragmental model and refined. The refined parameter values can then be used as initial estimates for the complex model. Differential equations for the complex model are fit simultaneously to tissue levels representing each compartment. By observation, the classical model fit the data more closely than the physiological model. Statistical moment theory is also applied to the topical infusion data to determine ocular pharmacokinetic parameters for clonidine. The calculated values are: corneal absorption rate constantk a , 0.00139 min?1; aqueous humor elimination rate constantk 10 , 0.0658min?1; mean residence timeMRT d , 35.6 min; apparent steadystate volume of distributionV ss, 0.530 ml; and ocular clearanceQ e , 14.9 =μl/min. The fraction absorbed from the single instillation is estimated as 0.0163. 相似文献
125.
126.
Francisco A. O. Júnior Clara R. Ruiz Yohanna de Oliveira Marco A. V. Barros Alexandre S. Silva Maria S. B. Santos Vinícius J. B. Martins Camille M. Balarini Valdir A. Braga 《Nutrients》2021,13(3)
Exploring an alternative to improve the clinical management of hypertension, we tested the hypothesis that food supplementation with coconut oil (EVCO), alone or combined with aerobic exercise training, could exert an antihypertensive effect (primary outcome) in patients with stage 1 hypertension. Forty-five hypertensive volunteers of both genders participated in a placebo-controlled clinical trial. The volunteers were submitted to 24-hour ambulatory blood pressure monitoring, analysis of blood pressure variability (BPV), measurement of serum malondialdehyde (MDA) and nutritional assessment. Results indicate that EVCO consumption had no adverse effects. The supplementation did not increase the caloric intake compared with placebo, and the dietary constituents were similar between groups, except for the saturated fats, especially lauric acid. The analysis of blood pressure indicated absence of antihypertensive effect of EVCO alone or combined with physical training. Furthermore, no effects on blood pressure variability and oxidative stress were observed in the supplemented hypertensive patients. Thus, despite the results observed in pre-clinical studies, the current clinical study did not provide evidence to support the use of coconut oil as an adjuvant in the management of hypertension in humans. 相似文献
127.
医院是为人类提供公共卫生服务的一个单位,其存在具有至关重要的影响意义,是人们医疗卫生事业的主要承担场所,医院所提供的公共卫生服务水平主要受到两个方面因素的影响,其一是医疗卫生发展水平,其二是人们生活水平;而这两种因素均受到人类社会经济发展水平的影响,由此可见,医院可以直接反映人类社会的发展水平,医院管理治疗会对其实际运行水平产生直接性影响,同时也侧面体现了我国公共卫生服务质量。因此,基于此种社会现实下,结合新形势要求,分析医院档案管理工作存在的弊端,并探讨创新途径具有至关重要的影响意义,这不仅是国家发展、社会发展的要求,同时也是医院实现可持续运行的根本条件,是当前医院刻不容缓需要解决的主要问题。 相似文献
128.
产后疼痛是困扰产妇的常见问题,如治疗不当可能会导致阿片类药物滥用、产后抑郁和疼痛长期存在等不良后果。因此,美国妇产科医师学会(American College of Obstetricians and Gynecologists,ACOG)于2021年9月提出了针对产后疼痛的临床共识,专门对产后疼痛的一般管理、阴道分娩、剖宫产术后、母乳喂养时及出院后疼痛的处置给出了治疗建议与指导,强调了阶梯式多模式药物镇痛方法与个体化用药原则。推荐临床用药可遵循“非阿片类镇痛药(如对乙酰氨基酚和非甾体抗炎药)—弱阿片类药物—强阿片类药物(必要时)”阶梯式给药原则,并可合理联合用药。对此进行简要介绍与要点解读。 相似文献
129.
李学勤 《南通大学学报(哲学社会科学版)》2001,17(4):85-89
国家“九五”期间重点科技攻关计划项目“夏商周断代工程” ,经过200位专家学者前后5年的集体努力 ,已于2000年9月通过验收 ,同年11月公布了《夏商周断代工程1996-2000年阶段成果报告 (简本 )》。这一项目采取自然科学与人文社会科学多学科结合的研究途径 ,制定了《夏商周年表》 ,为我国古代夏商周这一重要历史时期的年代学提供了科学依据 ,使进一步探索中国古代文明起源及其早期发展有了可靠的基础。 相似文献
130.
目的研究以带蒂复合组织瓣修复胸骨旁小切口术后胸壁缺损的可行性。方法观察尸体前胸壁深层结构的血供 规律,测量胸骨外侧缘与胸廊内动脉之间的距离,并在此基础之上设计出以胸阔内动脉为蒂的肋软骨助间肌瓣。结果 前胸壁深层各结构均由胸廓内动脉及其分支供血,胸廊内动脉里胸骨外侧缘的距离为1cm左右。紧挨胸骨外侧缘切开 肋软骨,可以避免胸廓内动脉的损伤。以该动脉为帮,可以保证数种肋软骨肋间肌瓣有良好的血供。结论用以胸廊内动 脉为蒂的肋软骨助间肌瓣修复心脏外科术后的胸壁缺损具有良好的可行性。 相似文献