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101.
Prematurity is the single greatest cause of morbidity and mortality in obstetrics. Families, health care services, and education systems experience the impact of prematurity for the lifetime of the preterm-born child. Health care providers have tried to lower the preterm birth rate with prevention both before and during pregnancy and intervention for symptomatic women. The inability of the health care system to significantly decrease the incidence of preterm birth continues to be a challenge. To further complicate the situation, new data shows that infants born between 34 and 37 weeks' gestation who were thought to have minimal long-term effects of preterm birth may be more at risk than previously appreciated. This article reviews evidence-based risk identification, prevention, and management of women experiencing preterm labor and birth.  相似文献   
102.
病理性近视眼的研究进展   总被引:5,自引:4,他引:1  
通过复习近年来相关文献,对近视眼发生发展机制与形觉剥夺之间的关系进行综合评述。认为近视眼的发生及眼轴延长与形觉剥夺有一定关系,深入研究其相关机制,对近视眼的早期防治具有重要意义。  相似文献   
103.
目的 构建高迁移率族蛋白 1(HMGB1)基因的反义真核表达载体 ,寻找胰腺癌基因治疗新途径。方法应用分子克隆技术构建HMGB1基因反义真核表达载体 pcDNA3 1/antisense HMGB1,转染胰腺癌细胞株PANC 1,通过逆转录 聚合酶链反应 (RT PCR)、免疫印迹法 (Westernblot)、噻唑蓝 (MTT)比色法检测转染 4 8h后胰腺癌细胞HMGB1基因表达和体外增殖活性的变化。结果 成功构建 pcDNA3 1/antisense HMGB1反义真核表达载体。所获反义表达载体 pcDNA3 1/antisense HMGB1转染可使PANC 1细胞HMGB1mRNA和蛋白表达水平显著降低 (P <0 0 1)。反义 pcDNA3 1/antisense HMGB1的导入能有效抑制PANC 1增殖活性 (P <0 0 1)。 结论 应用反义RNA技术阻断HMGB1基因的表达 ,能有效抑制癌细胞的体外增殖活性 ,为基因治疗提供了新思路  相似文献   
104.
目的 观察早期饮食干预对婴幼儿呼吸道变态反应疾病发展的影响。方法 选取2003年1月-2004年6月复旦大学附属儿科医院0~6月变态反应疾病高危婴儿176例,在进行环境控制的前提下,随机分为干预组(饮食干预)和非干预组,随访两组患儿变态反应疾病发生、发展的情况。结果 (1)在干预6、12、18个月后,干预组发生两种以上变态反应疾病的人数均显著少于非干预组,过敏症状的严重程度较非干预组也显著减轻(P〈0.005)。(2)饮食干预18个月后,两组患儿在吸入性过敏原筛查阳性比例上的差异没有显著性(χ^2=0.002,P=0.969),但干预组患儿的肺功能显著优于非干预组(P〈0.005)、干预组的食物过敏原筛查阳性比例显著低于非干预组(χ^2=8.91,P〈0.01)。结论 对变态反应性疾病高危婴儿进行饮食干预,能减轻或消除呼吸道变态反应疾病症状,改善肺功能。  相似文献   
105.
BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary.  相似文献   
106.
用单克隆抗体测定了移居高原的老年人重返平原后的T细胞亚群的变化结果:①移居西宁(2260m)组、天峻(3000m)组在西宁所测的OKT_3、OKT_4、OKT_8及OKT_4/OKT_8值与在苏州所测的当地老年人无差异。②移居西宁组急返平原后OKT_3、OKT_8水平明显低于返回平原后居住一年以上者(以下简称返回组)(P<0.01~0.001)但OKT_4/OKT_8无差异。③返回组与世居苏州老年人相比,前者OKT_3、OKT_4、OKT_8及OKT_4。OKT_8增高,其中OKT_3、OKT_4增高明显(P<0.01~0.02),作者认为长期移居高原返回平原后T细胞亚群也可能存在一“脱适应”阶段,即机体重新调整重新平衡的一种形式,这一阶段可能需一年以上。  相似文献   
107.
报道温州地区胃癌高发区瑞安塘下的致癌危险因素的调查情况,结果表明它是由多种致癌危险因素的综合影响。作者应用内镜活检在18000例慢性胃病患者中查出癌前病变(高危人群)1132例,经3月~14年活检随访,表明胃癌前病变有一定的可逆转性;癌变率较高的是胃溃疡(GU)+不典型增生(ATP)组、GU+慢性萎缩性胃炎(CAG)组及CAG+ATP组均为4.1%;总癌变率为3.1%。早癌检出率占胃癌总数的48.6%,为门诊早癌检出率的6.8倍。此方法简单、经济实用。  相似文献   
108.
瞄准前沿以人为本全面提升医院的综合竞争力   总被引:3,自引:3,他引:0  
介绍了医院创新工作思路和瞄准国际前沿,高起点培训专业技术人才,全面提升医院综合竞争力的主要做法及取得的成效.  相似文献   
109.
AIMS: Metabolic responses to manipulation of the plasma free fatty acid (FFA) concentration were assessed in six healthy men via cross-over design to determine whether FFAs independently influence insulin sensitivity. METHODS: Intramyocellular lipid (IMCL) was measured by proton magnetic resonance spectroscopy and insulin sensitivity via frequently sampled intravenous glucose tolerance test (IVGTT) after 67 h of two identical low carbohydrate/high fat (LC) diets which were used to elevate IMCL and plasma FFAs. To uncouple the influence of FFAs and IMCL on insulin sensitivity, FFAs were suppressed 30 min prior to and during IVGTT in one treatment [LC + nicotinic acid (NA)] by NA ingestion. RESULTS: Vastus lateralis IMCL was significantly elevated in LC (13.3 +/- 1.1 x 10(-3)) and LC + NA (13.5 +/- 1.1 x 10(-3)) (P < 0.01 for both), but was not different between conditions (P > 0.05). Plasma FFAs were raised in LC (0.79 +/- 0.08 mmol/l) and LC + NA (0.80 +/- 0.11 mmol/l) (P < 0.01 for both) and were significantly reduced by NA ingestion prior to (0.36 +/- 0.05 mmol/l, P < 0.01) and during IVGTT (P < 0.05) in LC + NA. Despite marked differences in plasma FFA availability, insulin sensitivity and glucose tolerance were not different between LC and LC + NA (P > 0.05 for both). CONCLUSIONS: Plasma FFAs appear to exert no immediate effect on insulin sensitivity/glucose tolerance independent of their action on intracellular lipid moieties. Further research is required to elucidate the duration of FFA suppression required to restore insulin sensitivity following lipid-induced insulin resistance.  相似文献   
110.
Abstract. The mechanisms responsible for the decreased high density lipoprotein (HDL) cholesterol levels associated with obesity and insulin resistance are not well understood. Lecithin: cholesterol acyltransferase (LCAT) and cholesterol ester transfer protein (CETP) are key factors in the esterification of cholesterol in HDL and the subsequent transfer of cholesteryl ester towards apolipoprotein B-containing lipoproteins. Phospholipid transfer protein (PLTP) may be involved in the regulation of HDL particle size. We therefore measured the activities of LCAT, CETP and PLTP using exogenous substrate assays, as well as lipids, lipoproteins, insulin and C-peptide in fasting plasma from eight healthy obese men (body mass index >27 kg m-2) and 24 non-obese subjects. The obese men had lower levels of HDL cholesterol (P<0·05) and higher levels of plasma triglycerides (P<0·05), insulin (P<0·05) and C-peptide (P<0·01), as compared to the quartile of subjects with the lowest body mass index (BMI <22·4 kg m-2). CETP and PLTP activities were elevated in the obese men by 35% (P<0·01) and by 15% (P<0·05), respectively. LCAT activity was comparable among the quartiles. Linear regression analysis showed that CETP activity was positively correlated with body mass index (P<0·02), fasting blood glucose (P7lt;0·05) and plasma C-peptide (P<0·05). PLTP activity was positively related to body mass index (P<0·01), waist to hip circumference ratio (P<0·001), as well as to fasting blood glucose (P<0·05) and plasma C-peptide (P<0·05) It is concluded that the activities of CETP and PLTP are influenced by adiposity and possibly by insulin resistance. Elevated lipid transfer protein activities may provide a mechanism that contributes to alterations in HDL in insulin resistant states.  相似文献   
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