全文获取类型
收费全文 | 39407篇 |
免费 | 3714篇 |
国内免费 | 2690篇 |
专业分类
耳鼻咽喉 | 200篇 |
儿科学 | 540篇 |
妇产科学 | 580篇 |
基础医学 | 4878篇 |
口腔科学 | 725篇 |
临床医学 | 4856篇 |
内科学 | 6512篇 |
皮肤病学 | 361篇 |
神经病学 | 2340篇 |
特种医学 | 1422篇 |
外国民族医学 | 23篇 |
外科学 | 4280篇 |
综合类 | 5816篇 |
现状与发展 | 12篇 |
一般理论 | 3篇 |
预防医学 | 2278篇 |
眼科学 | 975篇 |
药学 | 4074篇 |
16篇 | |
中国医学 | 1894篇 |
肿瘤学 | 4026篇 |
出版年
2024年 | 104篇 |
2023年 | 570篇 |
2022年 | 1324篇 |
2021年 | 1683篇 |
2020年 | 1376篇 |
2019年 | 1217篇 |
2018年 | 1303篇 |
2017年 | 1202篇 |
2016年 | 1145篇 |
2015年 | 1773篇 |
2014年 | 2099篇 |
2013年 | 1844篇 |
2012年 | 2910篇 |
2011年 | 3055篇 |
2010年 | 1867篇 |
2009年 | 1504篇 |
2008年 | 2094篇 |
2007年 | 2142篇 |
2006年 | 1941篇 |
2005年 | 2021篇 |
2004年 | 1384篇 |
2003年 | 1325篇 |
2002年 | 1095篇 |
2001年 | 886篇 |
2000年 | 1021篇 |
1999年 | 1085篇 |
1998年 | 685篇 |
1997年 | 742篇 |
1996年 | 564篇 |
1995年 | 526篇 |
1994年 | 468篇 |
1993年 | 329篇 |
1992年 | 316篇 |
1991年 | 336篇 |
1990年 | 295篇 |
1989年 | 264篇 |
1988年 | 241篇 |
1987年 | 230篇 |
1986年 | 195篇 |
1985年 | 150篇 |
1984年 | 106篇 |
1983年 | 86篇 |
1982年 | 41篇 |
1981年 | 51篇 |
1980年 | 39篇 |
1979年 | 33篇 |
1978年 | 29篇 |
1977年 | 27篇 |
1976年 | 20篇 |
1975年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
随着对肿瘤热疗和肿瘤免疫微环境(TIME)的深入研究,近年来热疗对TIME的作用越来越受到学者们的重视。本文就目前国内外研究进展,对热疗与TIME中几类主要免疫细胞和免疫相关细胞因子的影响及作用机制作一综述。全面而透彻的了解热疗对TIME的调控作用,有助于为肿瘤治疗提供新的思路和方法。 相似文献
25.
Fur-Hsing Wen Jen-Shi Chen Wen-Chi Chou Wen-Cheng Chang Wen Chi Shen Chia-Hsun Hsieh Siew Tzuh Tang 《Journal of pain and symptom management》2019,57(1):64-72
Context
Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.Objectives/Methods
We used multivariate hierarchical linear modeling to simultaneously evaluate associations between five distinct patterns of conjoint symptom distress and functional impairment (symptom-functional states) and subjective caregiving burden, QOL, and depressive symptoms in a convenience sample of 215 family caregiver–patient dyads. Data were collected every 2 to 4 weeks over patients' last 6 months.Results
Caregivers of patients in the worst symptom-functional states (States 3–5) reported worse subjective caregiving burden and depressive symptoms than those in the best two states, but the three outcomes did not differ between caregivers of patients in State 3 and States 4–5. Caregivers of patients in State 5 endured worse subjective caregiving burden and QOL than those in State 4. Caregivers of patients in State 4 suffered worse subjective caregiving burden and depressive symptoms but comparable QOL to those in State 2.Conclusion
Patients' five distinct, conjoint symptom-functional states were significantly and differentially associated with their caregivers' worse subjective caregiving burden, QOL, and depressive symptoms while caring for patients over their last 6 months. 相似文献26.
27.
Fuying Chen Linting Huang Changcan Li Jia Zhang Weiqin Yang Beibei Zhang Huaguo Li Dan Deng Jianying Liang Jinwen Shen Zhirong Yao Ming Li 《Clinical genetics》2020,98(2):179-184
Epidermolysis bullosa (EB) is a heritable blistering disorder. We performed a next-generation sequencing-based multigene panel test and successfully predicted 100% of the EB types, including, 36 EB simplex (EBS), 13 junctional EB (JEB), 86 dystrophic EB (DEB), and 3 Kindler EB. Chinese JEB and recessive DEB (RDEB) patients have relatively mild phenotypes; for severe type separately accounts for 45.5% and 23.8%, respectively. We identified 96 novel and 49 recurrent pathogenic variants in 11 genes, although we failed to detect the second mutation in one JEB and five RDEB patients. We identified one novel p.E475K mosaic mutation in the clinically normal mother of one out of 13 EBS patients with KRT5 mutations, one recurrent p.G2034R mosaic mutation, and one novel p.G2043R mosaic mutation in the clinically normal relatives of two out of 19 dominant DEB patients. This study shows that next-generation technology could be an effective tool in diagnosing EB. 相似文献
28.
目的 观察互动式歌唱表演对轻中度阿尔茨海默病(AD)患者抑郁、精神行为症状及运动训练参与率的影响。方法 选取符合入组条件≥60周岁AD患者63例,随机分为研究组(31例)和对照组(32例)。所有受试患者常规药物治疗及常规运动训练,对照组接受被动性音乐治疗,研究组接受以互动歌唱为主的主动性音乐治疗,1次/d,每次1小时,每周训练5天,持续干预6个月。于治疗前、治疗1个月后、治疗3个月后、治疗6个月后分别采用康奈尔痴呆抑郁量表(CSDD)评分、阿尔茨海默病病理行为(BEHAVE AD)评分、参与率进行评估。结果 治疗1个月、3个月后,研究组CSDD评分较治疗前均降低(P<0.05);治疗6个月后,研究组患者CSDD评分较治疗前、治疗1个月、3个月后均显著降低(P<0.05),且与对照组比较差异有统计学意义(P<0.05)。治疗1个月、3个月后,研究组BEHAVE AD评分较治疗前均降低(P<0.05);治疗6个月后,研究组患者BEHAVE AD评分较治疗前、治疗1个月、3个月后均显著降低(P<0.05),且与对照组比较差异有统计学意义(P<0.05)。治疗6个月后,两组运动训练参与率组间比较差异有统计学意义(P<0.05)。结论 互动式歌唱表演可能对改善轻中度AD患者的抑郁和精神行为症状有着积极的疗效,同时对提高受试者运动训练的参与率可能有着更积极的疗效。 相似文献
29.
Se-Jin Lee Adam Lehar Yewei Liu Chi Hai Ly Quynh-Mai Pham Michael Michaud Renata Rydzik Daniel W. Youngstrom Michael M. Shen Vesa Kaartinen Emily L. Germain-Lee Thomas A. Rando 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(49):30907
Myostatin (MSTN) is a transforming growth factor-β (TGF-β) family member that normally acts to limit muscle growth. The function of MSTN is partially redundant with that of another TGF-β family member, activin A. MSTN and activin A are capable of signaling through a complex of type II and type I receptors. Here, we investigated the roles of two type II receptors (ACVR2 and ACVR2B) and two type I receptors (ALK4 and ALK5) in the regulation of muscle mass by these ligands by genetically targeting these receptors either alone or in combination specifically in myofibers in mice. We show that targeting signaling in myofibers is sufficient to cause significant increases in muscle mass, showing that myofibers are the direct target for signaling by these ligands in the regulation of muscle growth. Moreover, we show that there is functional redundancy between the two type II receptors as well as between the two type I receptors and that all four type II/type I receptor combinations are utilized in vivo. Targeting signaling specifically in myofibers also led to reductions in overall body fat content and improved glucose metabolism in mice fed either regular chow or a high-fat diet, demonstrating that these metabolic effects are the result of enhanced muscling. We observed no effect, however, on either bone density or muscle regeneration in mice in which signaling was targeted in myofibers. The latter finding implies that MSTN likely signals to other cells, such as satellite cells, in addition to myofibers to regulate muscle homeostasis.Myostatin (MSTN) is a secreted signaling molecule that normally acts to limit skeletal muscle growth (for review, see ref. 1). Mice lacking MSTN exhibit dramatic increases in muscle mass throughout the body, with individual muscles growing to about twice the normal size (2). MSTN appears to play two distinct roles in regulating muscle size, one to regulate the number of muscle fibers that are formed during development and a second to regulate the growth of those fibers postnatally. The sequence of MSTN has been highly conserved through evolution, with the mature MSTN peptide being identical in species as divergent as humans and turkeys (3). The function of MSTN has also been conserved, and targeted or naturally occurring mutations in MSTN have been shown to cause increased muscling in numerous species, including cattle (3–5), sheep (6), dogs (7), rabbits (8), rats (9), swine (10), goats (11), and humans (12). Numerous pharmaceutical and biotechnology companies have developed biologic agents capable of blocking MSTN activity, and these have been tested in clinical trials for a wide range of indications, including Duchenne and facioscapulohumeral muscular dystrophy, inclusion body myositis, muscle atrophy following falls and hip fracture surgery, age-related sarcopenia, Charcot–Marie–Tooth disease, and cachexia due to chronic obstructive pulmonary disease, end-stage kidney disease, and cancer.The finding that certain inhibitors of MSTN signaling can increase muscle mass even in Mstn−/− mice revealed that the function of MSTN as a negative regulator of muscle mass is partially redundant with at least one other TGF-β family member (13, 14), and subsequent studies have identified activin A as one of these cooperating ligands (15, 16). MSTN and activin A share many key regulatory and signaling components. For example, the activities of both MSTN and activin A can be modulated extracellularly by naturally occurring inhibitory binding proteins, including follistatin (17, 18) and the follistatin-related protein, FSTL-3 or FLRG (19, 20). Moreover, MSTN and activin A also appear to share receptor components. Based on in vitro studies, MSTN is capable of binding initially to the activin type II receptors, ACVR2 and ACVR2B (also called ActRIIA and ActRIIB) (18) followed by engagement of the type I receptors, ALK4 and ALK5 (21). In previous studies, we presented genetic evidence supporting a role for both ACVR2 and ACVR2B in mediating MSTN signaling and regulating muscle mass in vivo. Specifically, we showed that mice expressing a truncated, dominant-negative form of ACVR2B in skeletal muscle (18) or carrying deletion mutations in Acvr2 and/or Acvr2b (13) have significantly increased muscle mass. One limitation of the latter study, however, was that we could not examine the consequence of complete loss of both receptors using the deletion alleles, as double homozygous mutants die early during embryogenesis (22). Moreover, the roles that the two type I receptors, ALK4 and ALK5, play in regulating MSTN and activin A signaling in muscle in vivo have not yet been documented using genetic approaches. Here, we present the results of studies in which we used floxed alleles for each of the type II and type I receptor genes in order to target these receptors alone and in combination in muscle fibers. We show that these receptors are functionally redundant and that signaling through each of these receptors contributes to the overall control of muscle mass. 相似文献