全文获取类型
收费全文 | 828篇 |
免费 | 67篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 17篇 |
妇产科学 | 17篇 |
基础医学 | 223篇 |
口腔科学 | 3篇 |
临床医学 | 122篇 |
内科学 | 127篇 |
皮肤病学 | 9篇 |
神经病学 | 44篇 |
特种医学 | 72篇 |
外科学 | 41篇 |
综合类 | 67篇 |
预防医学 | 104篇 |
眼科学 | 3篇 |
药学 | 17篇 |
1篇 | |
中国医学 | 15篇 |
肿瘤学 | 27篇 |
出版年
2024年 | 2篇 |
2023年 | 17篇 |
2022年 | 44篇 |
2021年 | 60篇 |
2020年 | 42篇 |
2019年 | 43篇 |
2018年 | 34篇 |
2017年 | 39篇 |
2016年 | 34篇 |
2015年 | 33篇 |
2014年 | 67篇 |
2013年 | 61篇 |
2012年 | 37篇 |
2011年 | 45篇 |
2010年 | 23篇 |
2009年 | 29篇 |
2008年 | 30篇 |
2007年 | 35篇 |
2006年 | 19篇 |
2005年 | 15篇 |
2004年 | 17篇 |
2003年 | 12篇 |
2002年 | 11篇 |
2001年 | 12篇 |
2000年 | 7篇 |
1999年 | 7篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 10篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1985年 | 8篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 5篇 |
1976年 | 3篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有910条查询结果,搜索用时 0 毫秒
61.
《Research in developmental disabilities》2014,35(5):1087-1097
Children with Developmental Coordination Disorder (DCD) experience considerable difficulties coordinating and controlling their body movements during functional motor tasks. Thus, it is not surprising that children with DCD do not perform well on tests of physical fitness. The aim of this study was to determine whether deficits in motor coordination influence the ability of children with DCD to perform adequately on physical fitness tests. A case–control study design was used to compare the performance of children with DCD (n = 70, 36 boys, mean age = 8y 1mo) and Typically Developing (TD) children (n = 70, 35 boys, mean age = 7y 9mo) on measures of isometric strength (hand-held dynamometry), functional strength, i.e. explosive power and muscular endurance (Functional Strength Measurement), aerobic capacity (20 m Shuttle Run Test) and anaerobic muscle capacity, i.e. muscle power (Muscle Power Sprint Test). Results show that children with DCD were able to generate similar isometric forces compared to TD children in isometric break tests, but were significantly weaker in three-point grip strength. Performance on functional strength items requiring more isolated explosive movement of the upper extremities, showed no significant difference between groups while items requiring muscle endurance (repetitions in 30 s) and items requiring whole body explosive movement were all significantly different. Aerobic capacity was lower for children with DCD whereas anaerobic performance during the sprint test was not. Our findings suggest that poor physical fitness performance in children with DCD may be partly due to poor timing and coordination of repetitive movements. 相似文献
62.
目的观察干细胞治疗联合有氧运动对急性心肌梗死大鼠左心室重塑的影响。方法采用结扎冠状动脉前降支方法将60只6周龄雄性Wistar大鼠制成急性心肌梗死动物模型, 并随机分为模型组、干细胞组、运动组及观察组, 同时选取10只健康Wistar大鼠纳入假手术组。干细胞组和观察组大鼠于造模成功后经尾静脉输注骨髓间充质干细胞悬液, 运动组和观察组大鼠于造模4周后给予跑台运动干预(每天运动60 min, 每周运动5 d, 连续运动8周)。于造模4周后及末次训练结束时利用递增负荷运动实验评估大鼠运动能力, 于末次训练结束时采用超声成像系统检测大鼠心脏结构及功能, 取左心室组织进行Masson染色并计算胶原容积分数, 采用实时荧光定量PCR技术检测大鼠心肌脑钠肽(BNP)、β-肌球蛋白重链(β-MHC)、α-MHC mRNA表达量以及α-MHC/β-MHC比值。结果与假手术组比较, 模型组力竭时间、力竭距离明显缩短, 最快跑速、左心室射血分数(LVEF)、左心室缩短分数(LVFS)、α-MHC表达量及α-MHC/β-MHC比值显著降低(P<0.05), 安静时心率、胶原容积分数、BNP和β-MHC表... 相似文献
63.
BackgroundChronic primary insomnia is characterized by long-term difficulties in maintaining and initiating sleep, too early waking up, poor mood, fatigue, impaired concentration and poor quality of life. Exercise training is recommended to prevent and alleviate sleep disorders.ObjectiveThe aim of the study was to investigate the influence of aerobic exercise training on quality of sleep, psychological wellbeing and immune system among subjects with chronic primary insomnia.Material and methodsEighty previously sedentary subjects with chronic primary insomnia subjects enrolled in this study, their age ranged from 35–56 years. All participants were randomly assigned to supervised aerobic exercise intervention group (group A, n=40) or control group (group B, n=40). Polysomnographic recordings for sleep quality assessment, Beck Depression Inventory (BDI), Profile of Mood States(POMS), Rosenberg Self-Esteem Scale (RSES), number of CD3+, CD4+, CD8+ T cells count and CD4/CD8 ratio were measured before and at the end of the study after six months.ResultsThere was a significant increase in the total sleep duration, sleep efficiency and sleep onset latency in group(A) after six months of aerobic exercise training, while, wake time after sleep onset and rapid eye movement (REM) latency significantly reduced after six months of aerobic training compared with values obtained prior to aerobic exercise training. Also, the mean values of BDI, POMS, CD3 count, CD4 count and CD8 count decreased significantly and the mean value of RSES significantly increased in group (A) after the aerobic exercise training, while the results of the control group were not significant. Moreover, there were significant differences between both groups at the end of the study.ConclusionExercise training can be considered as a non-pharmacological modalty for modifying sleep quality, psychological wellbeing and immune system among subjects with chronic primary insomnia. 相似文献
64.
目的 观察有氧运动对非酒精性脂肪肝大鼠肝组织雷帕霉素靶蛋白(mTOR)、核糖体蛋白S6激酶1(S6K1)、固醇调节元件结合蛋白1c(SREBP-1c)表达的影响。 方法 选取健康雄性SD大鼠30只,按随机数字表法分为正常组、模型组和运动组。正常组喂食基础饲料,模型组和运动组均喂食高脂饲料,运动组大鼠进行12周跑台训练。3组大鼠均于实验12周后取材,肝脏称重,并进行肝组织苏木精-伊红(HE)染色观察和肝组织炎症活动度评分,同时测定血清总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)、谷草转氨酶(AST)和谷丙转苷酶(ALT)含量的变化,采用免疫印迹方法检测肝组织mTOR、S6K1、SREBP-1c蛋白的表达。 结果 正常组大鼠肝脏组织形态学基本正常,肝索排列整齐,肝小叶结构完整清晰,未见脂肪变性及炎症细胞浸润;模型组大鼠可见弥漫性肝细胞脂肪变性,肝索紊乱,炎性细胞浸润;运动组大鼠肝索排列较模型组整齐,肝细胞脂滴明显减少,炎症细胞浸润减轻。运动组大鼠肝组织炎症活动度评分显著低于模型组(P<0.01);模型组大鼠血清TC、TG、FFA、ALT、AST水平均显著高于正常组(P<0.01);运动组大鼠血清TC、TG、FFA、ALT、AST水平均显著低于模型组(P<0.01)。模型组大鼠肝组织mTOR、S6K1、SREBP-1c的蛋白表达分别(1.12±0.24)、(1.34±0.35)、(0.84±0.12),均显著高于正常组(P<0.01);运动组大鼠肝组织mTOR、S6K1、SREBP-1c的蛋白表达分别为(0.54±0.18)、(0.61±0.21)、(0.41±0.15),均显著低于模型组(P<0.01)。 结论 有氧运动可以发挥防治非酒精性脂肪肝的作用,其机制可能与mTOR/S6K1/SREBP-1c信号通路的抑制相关。 相似文献
65.
Fadwa Al-Ghalib Al-Sharif Osama Hussien Al-Jiffri Shehab Mahmoud Abd El-Kader Eman Mohamed Ashmawy 《African health sciences》2014,14(1):11-16
Background
Patients with hemophilia A have low bone density than healthy controls. It is now widely recognized that physical activity and sports are beneficial for patients with hemophilia.Objective
To compare the effects of mild and moderate intensity treadmill walking exercises on markers of bone metabolism and hand grip strength in male patients with moderate hemophilia A.Material and Methods
Fifty male patients with moderate hemophilia, and age range from 25 to 45 years. The subjects were randomly assigned into 2 equal groups; the first group (A) received moderate intensity aerobic exercise training. The second group (B) received mild intensity aerobic exercise training.Results
There was a 32.1% and 24.8% increase in mean values of serum calcium and hand grip strength respectively and 22.7 % reduction in mean values of parathyroid hormone in moderate exercise training group (A). While there was a 15.1 % and 15 % increase in mean values of Serum Calcium and Hand grip strength respectively and 10.3 % reduction in mean values of parathyroid hormone in mild exercise training group(B). The mean values of serum calcium and hand grip strength were significantly increased, while the mean values of parathyroid hormone were significantly decreased in both groups . There were significant differences between mean levels of the investigated parameters in group (A) and group (B) after treatment.Conclusion
Moderate intensity aerobic exercise training on treadmill is appropriate to improve markers of bone metabolism and hand grip strength in male patients with hemophilia A. 相似文献66.
Shigenori Ito 《World journal of cardiology》2019,11(7):171-188
Aerobic capacity, which is expressed as peak oxygen consumption(VO_(2peak)), is well-known to be an independent predictor of all-cause mortality and cardiovascular prognosis. This is true even for people with various coronary risk factors and cardiovascular diseases. Although exercise training is the best method to improve VO_(2peak), the guidelines of most academic societies recommend 150 or75 min of moderate-or vigorous-intensity physical activities, respectively, every week to gain health benefits. For general health and primary and secondary cardiovascular prevention, high-intensity interval training(HIIT) has been recognized as an efficient exercise protocol with short exercise sessions. Given the availability of the numerous HIIT protocols, which can be classified into aerobic HIIT and anaerobic HIIT [usually called sprint interval training(SIT)],professionals in health-related fields, including primary physicians and cardiologists, may find it confusing when trying to select an appropriate protocol for their patients. This review describes the classifications of aerobic HIIT and SIT, and their differences in terms of effects, target subjects, adaptability, working mechanisms, and safety. Understanding the HIIT protocols and adopting the correct type for each subject would lead to better improvements in VO_(2peak) with higher adherence and less risk. 相似文献
67.
Borrel G Jézéquel D Biderre-Petit C Morel-Desrosiers N Morel JP Peyret P Fonty G Lehours AC 《Research in microbiology》2011,162(9):832-847
The atmospheric concentration of methane (CH4), a major greenhouse gas, is mainly controlled by the activities of methane-producing (methanogens) and methane-consuming (methanotrophs) microorganisms. Freshwater lakes are identified as one of the main CH4 sources, as it was estimated that they contribute to 6-16% of natural CH4 emissions. It is therefore critical to better understanding the biogeochemical cycling of CH4 in these ecosystems. In this paper, the effects of environmental factors on methanogenic and methanotrophic rates are reviewed and an inventory of the methanogens and methanotrophs at the genus/species level in freshwater lakes is given. We focus on the anaerobic oxidation of methane, which is a still poorly known process but increasingly reported in freshwater lakes. 相似文献
68.
运动心肺功能在冠心病PTCA术后康复评定中的应用 总被引:1,自引:2,他引:1
对15例心肌梗塞和心绞痛病人经皮冠状动脉成形术(PTCA)术后测定运动心肺功能。采用麦加菲心肺运动仪测定气体代谢指标,如摄氧量(VO2)、二氧化碳排出量(VCO2)、肺通气量(VE)、呼吸交换率(RER)、无氧阈值(AT)、氧脉搏(VO2/HR)等。根据病变程度和体能分为平板组(TET)和功率自行车组(EET)。15例病人当运动强度增加时摄氧量(VO2)缓慢上升,达到较低的峰值VO2,尤其EET且 相似文献
69.
子宫内膜异位症(Endometriosis,EMs)是育龄妇女的常见病,但其发病机制至今仍不清楚。越来越多的证据表明,低氧与EMs发生发展有密切的联系。在EMs异位组织中低氧诱导因子-1α(HIF-1α)的表达明显增高;HIF-1α通过调节雌激素产生、血管生成、细胞增殖和炎症等相关基因,促进EMs发展;HIF-1α是EMs有氧糖酵解过程中关键的调节因子;抑制HIF-1α的表达有助于抑制EMs的发生发展,表明HIF-1α在EMs的病理形成中的作用。本文介绍HIF-1α的研究进展,着重论述其在EMs中的作用。 相似文献
70.