首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   384篇
  免费   19篇
  国内免费   18篇
耳鼻咽喉   1篇
儿科学   17篇
妇产科学   7篇
基础医学   44篇
口腔科学   3篇
临床医学   23篇
内科学   80篇
神经病学   19篇
特种医学   4篇
外科学   27篇
综合类   51篇
预防医学   47篇
药学   86篇
中国医学   10篇
肿瘤学   2篇
  2023年   3篇
  2022年   8篇
  2021年   12篇
  2020年   10篇
  2019年   6篇
  2018年   7篇
  2017年   7篇
  2016年   13篇
  2015年   13篇
  2014年   19篇
  2013年   25篇
  2012年   13篇
  2011年   29篇
  2010年   22篇
  2009年   21篇
  2008年   24篇
  2007年   22篇
  2006年   18篇
  2005年   15篇
  2004年   23篇
  2003年   8篇
  2002年   8篇
  2001年   7篇
  2000年   6篇
  1999年   3篇
  1998年   4篇
  1997年   9篇
  1996年   5篇
  1995年   3篇
  1994年   4篇
  1993年   6篇
  1992年   2篇
  1991年   4篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   2篇
  1985年   3篇
  1984年   6篇
  1983年   4篇
  1982年   2篇
  1981年   3篇
  1979年   3篇
  1977年   4篇
  1976年   1篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1969年   1篇
  1968年   1篇
排序方式: 共有421条查询结果,搜索用时 15 毫秒
1.
目的:建立同时测定蜂蜜中果糖、葡萄糖、蔗糖、麦芽糖含量的高效液相色谱法。方法:采用高效液相色谱法,使用Prevail Carbohyrate ES色谱柱,乙腈-水(78∶22)为流动相,流速为1.0 mL·min-1,柱温30 ℃,检测器为蒸发光散射检测器,漂移管温度为105 ℃,氮气流速为3.0 mL·min-1,进样量为10 μL。以果糖为内参物,测定其与葡萄糖、蔗糖、麦芽糖的相对校正因子,利用该相对校正因子计算3种成分的含量,同时利用外标法测定3种糖类成分的含量,比较结果的差异。结果:果糖与葡萄糖、蔗糖、麦芽糖的相对校正因子分别为0.931、1.535、1.111,RSD均<2%;成分含量计算值与实测值间无显著性差异。结论:建立的一测多评法可用于蜂蜜中4种糖类成分的含量测定,可为蜂蜜的质量控制提供科学的理论依据。  相似文献   
2.
《Pregnancy hypertension》2015,5(4):308-314
PurposeThe incidence of pregnancies complicated by hyperglycemia and hypertension is increasing along with associated morbidities to mother and offspring. The high fructose diet is a well-studied model that induces hyperglycemia and hypertension in male rodents, but may not affect females. We hypothesized that the physiologic stress of pregnancy may alter metabolic responses to dietary fructose.Materials and methodsIn this study female Sprague–Dawley rats were divided into two gestational dietary groups: (1) 60% carbohydrate standard rat chow (Pregnant-S—controls) and (2) 60% fructose enriched chow (Pregnant-F). Body weight, blood pressure, blood glucose, triglycerides, and insulin were measured in pregnancy and during the post-partum period. Maternal organ weight and histological changes were also assessed after delivery.ResultsBy midpregnancy Pregnant-F rats had increased weight, elevated blood pressure, higher fasting glucose, and elevated triglycerides compared with Pregnant-S rats. Both groups demonstrated elevated gestational insulin levels with signs of insulin resistance (increased HOMA-IR). Pregnant-F rats showed significant histopathologic hepatic steatosis and renal tubular changes characterized by tubular dilation and glomerulosclerosis.ConclusionOur study provides a model in which dietary change during pregnancy can be examined. We demonstrate, moreover, that high dietary fructose ingestion in pregnant rats may result in profound systemic and pathologic changes not appreciated during routine pregnancy.  相似文献   
3.
目的:研究大黄酸对果糖诱导的痛风大鼠的肾脏保护作用。方法通过果糖喂养的方法制备痛风大鼠模型,连续灌胃大黄酸6周,测定血清肌酐、尿素氮、尿酸和黄嘌呤氧化酶含量等指标。结果大黄酸降低大鼠血清肌酐、尿素氮、尿酸和黄嘌呤氧化酶含量,改善了果糖诱导的大鼠肾脏结构的变化。结论大黄酸对果糖诱导的痛风大鼠具有肾脏保护作用。  相似文献   
4.
目的:观察高果糖饮食诱导的小鼠脂肪肝和肝脏氧化应激的发生时程变化,并探讨高果糖饮食致小鼠脂肪肝与氧化应激的关系。方法60只雄性C57BL/J6小鼠随机分为对照组、高果糖组,分别在喂养3 d、8周后测定小鼠空腹血糖( FBG)、空腹血清胰岛素( FINS)及肝脏甘油三酯( TG)含量,并测定各组小鼠肝脏氧化应激相关指标即丙二醛( MDA)、超氧化物歧化酶( SOD)、谷胱甘肽过氧化物酶( GSH-Px)及过氧化氢酶( CAT)水平的变化。结果喂养3 d后,与对照组相比,高果糖组小鼠的FBG、FINS无明显变化( P>0.05),而肝脏TG显著增加( P<0.01);喂养8周后,与对照组相比,高果糖组FBG、FINS、TG均显著增加( P<0.01);喂养3 d后,与对照组相比,高果糖组的MDA、SOD、GSH-Px以及CAT水平均无明显变化(P>0.05);喂养8周后,高果糖组的肝内MDA明显增加(P<0.01),SOD、GSH-Px及CAT活性均显著降低(P<0.01)。结论短期和长期高果糖喂养均可引起肝内脂质沉积,但短期高果糖喂养引起的肝脏脂质沉积不伴有氧化应激;长期高果糖喂养引起的肝脏脂质沉积伴有氧化应激,提示氧化应激与高果糖饮食诱导的脂肪肝发生发展有关,但介导机制有待进一步研究。  相似文献   
5.
The present study aimed to study the effects of exercise training (ET) performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP). Male Wistar rats receiving fructose overload in drinking water (100 g/L) were concomitantly trained on a treadmill for 10 weeks (FT group) or kept sedentary (F group), and a control group (C) was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT). Arterial pressure (AP) was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP) induced by fructose overload (FT vs F). The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF) band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg2), was prevented by ET (FT: 29±3, 3.4±0.7 mmHg2). Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01) and left IOP (r=0.64, P=0.003). Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01) and left IOP (r=-0.62, P=0.005). ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.  相似文献   
6.
7.
8.
Background and aimsThe association between dietary sugars and vascular damage has been scarcely examined out of the context of established cardiovascular disease. We aimed to investigate the association between different types of sugars with subclinical atheromatosis and arteriosclerosis, in individuals free of cardiovascular disease being, however, at moderate-to-high cardiovascular risk.Methods and resultsTwo 24-h dietary recalls were conducted to estimate sugars intake. Subclinical atheromatosis was assessed by B-mode ultrasonography and arteriosclerosis (arterial stiffness) via tonometry (carotid-to-femoral pulse wave velocity). Multiple logistic regression analysis was performed to determine the relationship of quartiles of total sugars, monosaccharides and disaccharides with atheromatosis and arteriosclerosis, adjusting for potential confounders [Odds Ratio (95%Confidence Interval)]. In 901 participants (52.4 ± 13.8 years, 45.2% males), total sugars intake was not associated with any type of subclinical vascular damage. Subjects at 4th quartile of lactose intake (15.3 ± 5.5 g/day) had lower probability to present atheromatosis compared to those at 1st quartile (0.00 ± 0.01 g/day) even in the fully adjusted model [0.586 (0.353–0.974)]. Subjects at 3rd quartile of total disaccharides intake and particularly sucrose (15.1 ± 2.2 g/day) had higher probability to present arteriosclerosis compared to those at 1st quartile (3.0 ± 1.9 g/day) even after adjustment for all potential confounders [2.213 (1.110–4.409)].ConclusionsOverall, the present data suggest a distinct role of each type of sugars on vascular damage. These observations highlight the need for further studies investigating not only foods rich in sugars, but sugars as separate components of food as they probably contribute via different ways on the development of arterial pathologies.  相似文献   
9.
10.
目的:观察内质网应激(ERS)抑制剂4-苯基丁酸(4-PBA)对高果糖饮食喂养大鼠肝脏氧化应激的影响,以探讨ERS在高果糖喂养诱导脂肪肝中的介导作用及其与氧化应激的关系。方法雄性Wistar大鼠分为对照组、高果糖组和4-PBA组[自高果糖喂养4周后给予4-PBA 0.35 g/(kg·d)],8周后处死大鼠并测定肝脏甘油三酯(TG)含量。 PCR法检测ERS标志物葡萄糖调节蛋白78(GRP78)的基因表达。测定细胞中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活性及细胞中丙二醛(MDA)的含量。 Western blot法检测肝C/EBP同源蛋白( CHOP)。结果与对照组相比,高果糖组的肝脏TG含量、GRP78基因表达、CHOP蛋白表达显著增加(P<0.01),与高果糖组比较,4-PBA上述指标显著降低(P<0.01)。与对照组相比,高果糖组大鼠的SOD、GSH-Px、CAT活性下降,MDA含量升高(P均<0.01),而4-PBA组的SOD、GSH-Px、CAT活性高于高果糖组,MDA含量低于高果糖组(P均<0.01)。结论长期高果糖喂养可诱导肝脏ERS和氧化应激,ERS抑制剂4-PBA可改善高果糖饮食诱导的肝脏氧化应激。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号