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41.
Among the numerous signaling pathways involved in tumorigenesis, PI3K‐AKT‐mTOR is a key one that regulates diverse cellular functions. However, its prognostic value in esophageal carcinoma remains unclear. In our study, we examined the immunohistochemical expression of phosphorylated (p‐) AKT, mTOR, p70S6K and 4E‐BP1 along with the mutational status of PIK3CA and AKT1 genes by High Resolution Melting Analysis and Pyrosequencing in 44 esophageal carcinomas. The results were correlated with the clinicopathological characteristics of the patients in an effort to define their possible prognostic significance. Total p‐mTOR cytoplasmic expression, assessed in 10 random areas, was positively correlated with tumor stage (Kruskal–Wallis ANOVA, I/II vs III/IV, p = 0.0500). Μoreover, maximum p‐mTOR cytoplasmic immunoexpression, estimated in hot spot areas, was positively associated with tumor grade (Mann–Whitney U test, I/II vs III, p = 0.0565). Interestingly, p‐4E‐BP1 immunoreactivity was negatively correlated with tumor histological grade (Mann–Whitney U test, I/II vs III, p = 0.0427). No mutation was observed in exons 9 and 20 of PIK3CA gene and in exon 4 of AKT1 gene. In conclusion, our findings depict the presence of activated PI3K/AKT/mTOR pathway in esophageal cancer bringing forward p‐mTOR and p‐4E‐BP1 for their potential role in esophageal carcinogenesis. Additional studies are warranted to validate our findings.  相似文献   
42.
金银花分子生物学研究进展   总被引:1,自引:0,他引:1  
分子生物学(molecular biology)是从分子水平阐明生命现象和本质的科学,其发展为传统生药学的研究提供了新的生物技术和方法。金银花作为常用大宗药材之一,国内外学者在深入研究传统方法的基础上,采用分子生物学手段对其展开真伪鉴别、品质评价和控制等方面的相关研究,并取得了一定成果。该文主要综述了近年来分子生物学技术方法在金银花鉴别、有效成分生物合成的分子机制以及胁迫条件下次生代谢产物积累的分子机制研究,并针对基于杂交技术的标记(RFLP)、基于PCR的分子标记(RAPD,AFLP,SSR,ISSR)和基于DNA序列分析的SNP及DNA条形码对金银花的多样性识别、诊断、鉴定等方面进行了详细的总结,同时提出可以采用多组学技术,构建系统生物学技术和平台,建立次生代谢产物生物合成的相关模型,从而更好地研究金银花活性成分生物合成的分子机制以及药用植物在环境胁迫下的相关代谢产物的合成和积累等生命活动规律并进行调控,为进一步推动金银花现代化及其他中药资源的开发利用提供支撑与参考。  相似文献   
43.
[目的]研究超敏C反应蛋白(hs-CRP)、总抗氧化状态(TAS)联合血脂检测在早老性痴呆症诊断中的应用价值:[方法]选择浦东新区精神卫生中心早老性痴呆专科门诊患者54例,作超敏C反应蛋白、总抗氧化状态与血脂检测。[结果]与对照组比较,实验组hs-CRP、TAS差异非常显著,t1=4.55,t2=2.79,P1〈0.001,P2〈0.01;血脂中甘油三酯、低密度脂蛋白胆固醇、载脂蛋白B、Lp(a)差异显著;t1=3.01,P1〈0.01,t2=2.21,P2〈0.05,t3=2.64,P3〈0.01,t4=1.91,P4〈0.05。[结论]超敏C反应蛋白、总抗氧化状态联合血脂(甘油三酯、低密度脂蛋白胆固醇、载脂蛋白B、Lp(a))检测对实验室诊断早老性痴呆症具有较好敏感性和特异性,临床应用前景乐观。  相似文献   
44.
A review of the effectiveness of aspartame in helping with weight control   总被引:1,自引:0,他引:1  
Summary Strategies to reverse the upward trend in obesity rates need to focus on both reducing energy intake and increasing energy expenditure. The provision of low‐ or reduced‐energy‐dense foods is one way of helping people to reduce their energy intake and so enable weight maintenance or weight loss to occur. The use of intense sweeteners as a substitute for sucrose potentially offers one way of helping people to reduce the energy density of their diet without any loss of palatability. This report reviews the evidence for the effect of aspartame on weight loss, weight maintenance and energy intakes in adults and addresses the question of how much energy is compensated for and whether the use of aspartame‐sweetened foods and drinks is an effective way to lose weight. All studies which examined the effect of substituting sugar with either aspartame alone or aspartame in combination with other intense sweeteners on energy intake or bodyweight were identified. Studies which were not randomised controlled trials in healthy adults and which did not measure energy intakes for at least 24 h (for those with energy intakes as an outcome measure) were excluded from the analysis. A minimum of 24‐h energy intake data was set as the cut‐off to ensure that the full extent of any compensatory effects was seen. A total of 16 studies were included in the analysis. Of these 16 studies, 15 had energy intake as an outcome measure. The studies which used soft drinks as the vehicle for aspartame used between 500 and about 2000 ml which is equivalent to about two to six cans or bottles of soft drinks every day. A significant reduction in energy intakes was seen with aspartame compared with all types of control except when aspartame was compared with non‐sucrose controls such as water. The most relevant comparisons are the parallel design studies which compare the effects of aspartame with sucrose. These had an overall effect size of 0.4 standardised difference (SD). This corresponds to a mean reduction of about 10% of energy intake. At an average energy intake of 9.3 MJ/day (average of adult men and women aged 19–50 years) this is a deficit of 0.93 MJ/day (222 kcal/day or 1560 kcal/week), which would be predicted (using an energy value for obese tissue of 7500 kcal/kg) to result in a weight loss of around 0.2 kg/week with a confidence interval 50% either side of this estimate. Information on the extent of compensation was available for 12 of the 15 studies. The weighted average of these figures was 32%. Compensation is likely to vary with a number of factors such as the size of the caloric deficit, the type of food or drink manipulated, and timescale. An estimate of the amount of compensation with soft drinks was calculated from the four studies which used soft drinks only as the vehicle. A weighted average of these figures was 15.5%. A significant reduction in weight was seen. The combined effect figure of 0.2 SD is a conservative figure as it excludes comparisons where the controls gained weight because of their high‐sucrose diet and the long‐term follow‐up data in which the aspartame groups regained less weight than the control group. An effect of 0.2 SD corresponds to about a 3% reduction in bodyweight (2.3 kg for an adult weighing 75 kg). Given the weighted average study length was 12 weeks, this gives an estimated rate of weight loss of around 0.2 kg/week for a 75‐kg adult. The meta‐analyses demonstrate that using foods and drinks sweetened with aspartame instead of sucrose results in a significant reduction in both energy intakes and bodyweight. Meta‐analyses both of energy intake and of weight loss produced an estimated rate of weight loss of about 0.2 kg/week. This close agreement between the figure calculated from reductions in energy intake and actual measures of weight loss gives confidence that this is a true effect. The two meta‐analyses used different sets of studies with widely differing designs and controls. Although this makes comparisons between them difficult, it suggests that the final figure of around 0.2 kg/week is robust and is applicable to the variety of ways aspartame‐containing foods are used by consumers. This review has shown that using foods and drinks sweetened with aspartame instead of those sweetened with sucrose is an effective way to maintain and lose weight without reducing the palatability of the diet. The decrease in energy intakes and the rate of weight loss that can reasonably be achieved is low but meaningful and, on a population basis, more than sufficient to counteract the current average rate of weight gain of around 0.007 kg/week. On an individual basis, it provides a useful adjunct to other weight loss regimes. Some compensation for the substituted energy does occur but this is only about one‐third of the energy replaced and is probably less when using soft drinks sweetened with aspartame. Nevertheless, these compensation values are derived from short‐term studies. More data are needed over the longer term to determine whether a tolerance to the effects is acquired. To achieve the average rate of weight loss seen in these studies of 0.2 kg/week will require around a 220‐kcal (0.93 MJ) deficit per day based on an energy value for obese tissue of 7500 kcal/kg. Assuming the higher rate of compensation (32%), this would require the substitution of around 330 kcal/day (1.4 MJ/day) from sucrose with aspartame (which is equivalent to around 88 g of sucrose). Using the lower estimated rate of compensation for soft drinks alone (15.5%) would require the substitution of about 260 kcal/day (1.1 MJ/day) from sucrose with aspartame. This is equivalent to 70 g of sucrose or about two cans of soft drinks every day.  相似文献   
45.
目的 探讨气体信号分子硫化氢(H2S)及一氧化氮(NO)在高原高血压的病理生理意义。方法 平原体检正常者进入海拔5000m高原(1~3)月期间,在高原暴露时间、劳动强度及生活条件相同的施工群体中随机抽样127人。依血压变化将其分为高原高血压(Ⅰ~Ⅲ级)组78人(进一步分为收缩期高原高血压组与舒张期高原高血压组),高原正常血压组49人,采取肘静脉血,采用敏感硫电极法测定其H2S浓度,Griess法测定血清NO含量。结果 高原高血压组、收缩期高原高血压组、舒张期高原高血压组的血清H2S与NO平均含量均显著增加,分别比正常血压组高34.5%,36.9%,31.7%(均P〈0.001)与28.4%,33.1%,39.7%,(均P〈0.05),尤以H2S更为突出;随着血压分级程度的升高H2S与NO血清含量相应增高,也以H2S更显著(R^2=0.918);H2S与NO、舒张压间均有密切正相关关系及良好的拟和优度、与氧饱和度呈显著的负相关与拟和优度(R^2=0.374,P=0.001)。结论 H2S与NO的代谢失常可能参与了高原高血压发病过程。  相似文献   
46.
47.
目的 观察高转换型肾性骨病中骨保护素及其配体 (OPG,RANKL)的表达,并与骨形态计量学指标进行相关分析。 方法 选择10例慢性肾衰尿毒症患者和3例正常人进行髂骨活检术,获得骨组织标本。采用免疫组化方法检测OPG和RANKL蛋白质的表达。采用全自动图像分析系统进行骨组织形态计量学测定。结果 10例慢性肾衰尿毒症患者经骨病理学检查证实均为高转换型骨病,以破骨细胞活化形成骨吸收陷窝伴或不伴骨矿化不全为特点。免疫组化显示尿毒症患者骨组织中以RANKL阳性表达为主。与正常对照相比,RANKL阳性表达细胞数目显著增加,OPG阳性表达细胞数目显著减少。尿毒症患者RANKL的阳性表达细胞数目与骨吸收面积和破骨细胞数目呈显著正相关。结论 高转换型肾性骨病中,PTH的溶骨作用可能是通过OPG/RANKL/RANK系统介导的。  相似文献   
48.
目的 探讨氯氮平、氟哌啶醇和氯丙嗪对慢性精神分裂症患者的糖、脂代谢和体质量的影响。方法 对服用氯氮平(89例,氯氮平组),服用氟哌啶醇(87例,氟哌啶醇组)及服用氯丙嗪(83例,氯丙嗪组)治疗的慢性精神分裂症患者于治疗前后的不同时间进行血糖、胰岛素、血脂及体质量测定,并做相关因素分析。结果 氯氮平组治疗第90天和第180天空腹血糖异常(空腹血浆血糖〉7.0mmo/L)的发生率分别为8%及24%,氟哌啶醇组分别为1%和2%,氯丙嗪组分别为1%及4%。治疗第90天氯氮平组和氯丙嗪组的空腹及餐后2h血糖浓度均较治疗前升高,治疗第180天的血糖浓度高于第90天,氟哌啶醇组各时点的变化则不明显;差异均有统计学意义(P均〈0.01)。治疗第90天,氯氮平组的体质量平均高于治疗前5.5%,氯丙嗪组高于治疗前4.8%;治疗第180天两组分别高于治疗前9.1%和7.4%;氟哌啶醇组则无明显变化;三组间的差异有统计学意义(P〈0.01)。三组患者治疗第180天的胰岛素浓度均高于治疗前,差异均有统计学意义(P均〈0.01),但三组间的差异无统计学意义(P〉0.05)。氯氮平组和氯丙嗪组的胆固醇和甘油三酯浓度均高于治疗前,差异均有统计学意义(P均〈0.01),氟哌啶醇组则无明显变化。治疗第180天氯氮平组和氯丙嗪组患者血糖、胰岛素、血脂浓度与体质量均有一定相关性(r=0.23-0.39);氯氮平组的血糖、体质量、血脂代谢还与血药浓度呈显著性相关(r=0.28-0.62),差异均有统计学意义(P〈0.05或〈0.01)。结论 氯氮平和氯丙嗪治疗影响慢性精神分裂症患者的糖、脂代谢及体质量。  相似文献   
49.
BACKGROUND: Decreased plasma adiponectin is associated with impaired endothelial function and, thereby, increased risk for cardiovascular events. Glucocorticoid (GC) affects vascular endothelial cells either favourably or harmfully depending upon the dosages and duration. We examined the effect of GC pulse therapy on vascular endothelial function. METHODS: Fourteen young patients with IgA nephropathy were evaluated for flow-mediated vasodilation (FMD), plasma levels of adiponectin both in high molecular weight (HMW adiponectin) form and in single molecular form (total adiponectin), hepatocyte growth factor (HGF), asymmetric dimethylarginine (ADMA), and high-sensitive C-reactive protein, before and after a course of GC pulse therapy. RESULTS: GC pulse therapy significantly decreased FMD (from 7.2 +/- 2.6 to 5.7 +/- 2.5%, P < 0.01). Meanwhile, plasma adiponectin levels were significantly augmented (total adiponectin: from 10.2 +/- 4.0 to 12.1 +/- 6.3 microg/ml, P < 0.05; HMW: from 6.5 +/- 3.2 to 7.7 +/- 3.3 microg/ml, P < 0.05). In parallel, elevated concentrations of serum HGF (from 0.28 +/- 0.12 to 0.63 +/- 0.38 ng/ml, P < 0.01) and plasma ADMA (from 0.45 +/- 0.07 to 0.53 +/- 0.04 nmol/ml, P < 0.05) were observed. CONCLUSIONS: GC pulse therapy impaired endothelial function while increasing plasma adiponectin levels, which may in turn restore the endothelial function in patients with IgA nephropathy.  相似文献   
50.
Background: Among gastric restrictive operations, the procedure of choice is still controversial. The aim of this study is to compare the results of two different gastric restrictive procedures: vertical banded gastroplasty (VBG) and stoma adjustable silicone gastric banding (ASGB). Methods: Between 1991 and 1996, 51 patients were treated surgically for morbid obesity: 27 underwent VBG and 24 underwent ASGB. Preoperative body weight (BW), body mass index (BMI) and percentage of ideal body weight (% IBW) were (mean ± SD): 145.7 ± 45.3 kg; 53.9 ± 15.9 kg/m2; 249.1 ± 73.5% respectively in the VBG group. Corresponding figures for the ASBG group were 132.5 ± 22.7 kg; 46.9 ± 7.8 kg/m2 and 207.2 ± 35.0%. Results: In the VBG group, the median follow-up period was 26 months (range: 7-47). Eighteen months after the operation BW, BMI, % IBW and percentage of excess weight loss (% EWL) were 85.5 ± 26.8 kg, 31.9 ± 9.8 kg/m2, 145.4 ± 43.9% and 74 ± 1% respectively. Complications included incisional hernia (n = 1), and bowel obstruction (n = 1). One patient died of acute myocardial infarction on the third postoperative day. In the ASGB group, median follow-up time was 19.7 months (range: 18-26). At 18 months postoperation BW, BMI, % IBW and % EWL values were 86.6 ± 20.6 kg 30.6 ± 6.6 kg/m2 140.6 ± 29.3% and 64 ± 1% respectively. Gastric wall erosion occurred in two patients and the bands had to be removed. These patients underwent VBG 6 months later. Complications encountered in this group were incisional hernia (n = 1), outlet stenosis and reflux esophagitis (n = 1), reservoir leakage (n = 1) and gastrointestinal bleeding (n = 1). Two patients died of pulmonary embolism and acute gastrointestinal bleeding. Conclusions: Weight reduction was not statistically significant between the two groups. ASGB was easier to perform and less invasive than VBG.  相似文献   
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