全文获取类型
收费全文 | 12674篇 |
免费 | 697篇 |
国内免费 | 177篇 |
专业分类
耳鼻咽喉 | 87篇 |
儿科学 | 289篇 |
妇产科学 | 60篇 |
基础医学 | 1572篇 |
口腔科学 | 266篇 |
临床医学 | 563篇 |
内科学 | 1263篇 |
皮肤病学 | 46篇 |
神经病学 | 956篇 |
特种医学 | 188篇 |
外科学 | 714篇 |
综合类 | 1260篇 |
预防医学 | 2683篇 |
眼科学 | 65篇 |
药学 | 2969篇 |
3篇 | |
中国医学 | 292篇 |
肿瘤学 | 272篇 |
出版年
2023年 | 154篇 |
2022年 | 206篇 |
2021年 | 589篇 |
2020年 | 354篇 |
2019年 | 355篇 |
2018年 | 352篇 |
2017年 | 330篇 |
2016年 | 354篇 |
2015年 | 375篇 |
2014年 | 706篇 |
2013年 | 977篇 |
2012年 | 666篇 |
2011年 | 726篇 |
2010年 | 548篇 |
2009年 | 612篇 |
2008年 | 540篇 |
2007年 | 504篇 |
2006年 | 465篇 |
2005年 | 433篇 |
2004年 | 368篇 |
2003年 | 265篇 |
2002年 | 246篇 |
2001年 | 205篇 |
2000年 | 195篇 |
1999年 | 176篇 |
1998年 | 162篇 |
1997年 | 162篇 |
1996年 | 116篇 |
1995年 | 117篇 |
1994年 | 119篇 |
1993年 | 89篇 |
1992年 | 140篇 |
1991年 | 124篇 |
1990年 | 124篇 |
1989年 | 118篇 |
1988年 | 115篇 |
1987年 | 90篇 |
1986年 | 79篇 |
1985年 | 152篇 |
1984年 | 141篇 |
1983年 | 99篇 |
1982年 | 124篇 |
1981年 | 89篇 |
1980年 | 105篇 |
1979年 | 101篇 |
1978年 | 72篇 |
1977年 | 65篇 |
1976年 | 73篇 |
1975年 | 56篇 |
1973年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 97 毫秒
1.
发作性睡病是致残性白天睡眠增多的最常见原因之一,其治疗旨在减少白天睡眠增多和猝倒,改善夜间睡眠紊乱、睡眠瘫痪及与睡眠有关的幻觉。2019年,组胺H3受体拮抗剂替洛利生(Pitolisant)和多巴胺及去甲肾上腺素再摄取抑制剂索利氨酯(Solriamfetol)分别在欧盟和美国上市,前者具有促醒和抗猝倒作用,后者也有促醒作用,且戒断症状和滥用的发生率更低。目前,控释型羟丁酸钠(FT218)、低钠型羟丁酸盐(JZP-258)、选择性去甲肾上腺素再摄取抑制剂(瑞波西汀,又称AXS-12)以及莫达非尼联合氟卡尼制剂(THN102)等药物仍在开发和测试中,均可作为治疗发作性睡病相关白天睡眠增多和猝倒的潜在药物。本文重点介绍这些最近研发的发作性睡病治疗药物。 相似文献
2.
3.
Eglantina Idrizaj Rachele Garella Roberta Squecco Maria Caterina Baccari 《World journal of gastroenterology : WJG》2020,26(20):2472-2478
The regulation of food intake is a complex mechanism, and the hypothalamus is the main central structure implicated. In particular, the arcuate nucleus appears to be the most critical area in the integration of multiple peripheral signals.Among these signals, those originating from the white adipose tissue and the gastrointestinal tract are known to be involved in the regulation of food intake.The present paper focuses on adiponectin, an adipokine secreted by white adipose tissue, which is reported to have a role in the control of feeding by acting centrally. The recent observation that adiponectin is also able to influence gastric motility raises the question of whether this action represents an additional peripheral mechanism that concurs with the central effects of the hormone on food intake. This possibility, which represents an emerging aspect correlating the central and peripheral effects of adiponectin in the hunger-satiety cycle, is discussed in the present paper. 相似文献
4.
5.
《Journal of the Academy of Nutrition and Dietetics》2022,122(6):1099-1113.e3
BackgroundLittle is known about breakfast habits of the Latin American (LA) population to support nutritional recommendations for a balanced breakfast in this region.ObjectiveTo evaluate the nutritional composition of breakfast in the LA population and to propose recommendations for a balanced breakfast.DesignThis multicenter cross-sectional study evaluated food and nutrient intake of nationally representative samples of urban populations of 8 LA countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela) in 2014-2015.Participants/settingThe sample comprised 8714 participants from the Latin American Study of Nutrition and Health, aged 15 to 65 years, randomly recruited according to geographical location, sex, age, and socioeconomic level.Main outcome measuresTwo 24-hour recalls were used to examine dietary intake. Breakfast consumers were stratified by tertiles of Nutrient-Rich Foods Index 9.3 (NRF9.3) to assess the overall diet quality of individuals. Nutrient intake at breakfast of those in the upper tertile of NRF9.3 pooled for the 8 countries was used as a reference for the development of recommendations for LA adolescents and adults.Statistical analysesComparison of food and nutrient intake of breakfast across NRF9.3 tertiles were analyzed using the Kruskal-Wallis rank sum test.ResultsOverall breakfast was an important contributor to protein, carbohydrate, and B vitamin intakes but also to added sugar and total and saturated fat intakes relative to daily intakes. Individuals in the upper NRF9.3 tertile had higher intake of key micronutrients such as calcium and potassium at breakfast compared with other tertiles. White breads/rolls/tortillas were the most consumed food group (60%), followed by butter/margarine (40%) and coffee/tea without milk (34%-50%).ConclusionsBreakfast contributed to the daily intake of B vitamins, protein, and carbohydrates but also added sugar and total and saturated fat intakes for all countries. The proposed recommendations support the nutrient density of existing highest-quality breakfast in the LA population while addressing concerns about nutrients to be encouraged or reduced. 相似文献
6.
7.
8.
丙戊酸钠治疗对血清瘦素、体重指数的影响 总被引:1,自引:0,他引:1
目的服用丙戊酸钠(VPA)抗癫痫治疗的患者,15%~70%的成人可发生体重增加[1-2],而瘦素在体重和能量平衡的调节中起重要影响,近年来许多研究表明VPA引起的体重改变可能与瘦素有关。探讨丙戊酸钠抗癫痫治疗对血清瘦素的影响,该影响与患者体重改变的相关性,以及瘦素的可能机制。方法以丙戊酸钠治疗超过3个月的33例癫痫患者为治疗组,20例未经丙戊酸钠治疗癫痫患者作为对照组来比较,检测患者体重、身高、血清瘦素水平,比较两组的体重指数(BMI)、血清瘦素水平。结果丙戊酸钠治疗组的血清瘦素(8.8503±4.7924)ug/ml与对照组(2.8490±1.3962)ug/ml比较有增高,治疗组BMI(23.7202±2.5182)高于对照组(20.8468±1.6815)。结论丙戊酸钠治疗可能引起血清瘦素、体重指数增高,很可能通过诱导导致瘦素抵抗的机制之一,从而导致患者体重增加。 相似文献
9.
Christiana Winkler Barbara Frick Katharina Schroecksnadel Harald Schennach Dietmar Fuchs 《Food and chemical toxicology》2006,44(12):2003-2007
Antioxidant preservatives prolong the quality of food and ensure the nutritional adequacy, palatability and safety of many processed foods and beverages. Effects of sodium sulfite (E221) and sorbic acid (E200) were investigated in human peripheral blood mononuclear cells (PBMC) which were purified from blood of healthy donors. Cells were stimulated with the mitogen phytohaemagglutinin in vitro, which induces proliferation of T-cells and the production of Th1-type cytokines like interferon-γ. The latter triggers enzyme indoleamine (2,3)-dioxygenase, which degrades tryptophan, and GTP cyclohydrolase I, which leads to increased neopterin production, in monocyte-derived macrophages. Sodium sulfite and sorbic acid suppressed both these biochemical changes in a dose-dependent way (P < 0.01 at 1 mM sodium sulfite and 50 mM sorbic acid). Data demonstrate a suppressive influence of sodium sulfite and sorbic acid on the activated Th1-type immune response. 相似文献
10.
透明质酸钠对大鼠成肌细胞增殖和分化的影响 总被引:3,自引:2,他引:1
目的 研究透明质酸钠对成肌细胞增殖和分化的影响。方法 采用酶消化法将新生SD大鼠骨骼肌组织分离、纯化、原代培养及传代培养;取第3代成肌细胞,分别加入浓度为0.05%、0.1%及0.2%的透明质酸钠溶液作为生长培养基行体外培养为实验A、B及C组,加入常规生长培养基为对照D组,观察各组成肌细胞增殖情况,并采用细胞计数及MTT法绘制生长曲线。另选择0.1%透明质酸钠融合培养基行体外成肌细胞培养,常规融合培养基作对照,观察透明质酸钠对成肌细胞分化功能的影响。结果A、B及C组成肌细胞增殖表现相似,2d时进入对数生长期,4d时均达顶峰;D组成肌细胞于3d时进入对数生长期,5d时细胞数倍增,6d时达顶峰。MTT法所测吸光度(A)值的变化反映成肌细胞的增殖情况,与细胞计数的结果一致,以B组细胞增殖作用最明显,B组A值在2~8d时均高于C、D组(P〈0.05),8d时高于A组(P〈0.05)。0.1%透明质酸钠融合培养基中的成肌细胞融合率较低且上升缓慢,7d时融合率最高,为11.7%;常规融合培养基成肌细胞融合率于6d时达到峰值,约为35.0%。结论 透明质酸钠与成肌细胞的细胞相容性较好,可以作为良好的成肌细胞培养基。 相似文献