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141.
142.
Although unstable angina can be initially controlled with medical therapy in most patients, there is a high incidence of subsequent death, myocardial infarction, or need for coronary bypass surgery to control symptoms. Identification at the time of presentation of the patient likely to do poorly on continued medical therapy would be useful in advising consideration of surgical therapy. Since coronary arterial spasm may have a significant role in the pathophysiology of unstable angina in some patients, the recently developed calcium channel antagonists may therefore be of particular benefit in the medical therapy of unstable angina. One hundred thirty-eight patients were entered into a randomized double-blind study of the efficacy of adding nifedipine to conventional treatment of unstable angina (nitrates and beta-blockers) and were followed for 18 months. Of these patients, 104 underwent coronary arteriography. A multivariate Cox's hazard function analysis was applied to variables selected from the history, electrocardiographic (ECG) changes during chest pain, and from scintigraphic and coronary arteriographic data to determine those variables most predictive of response to medical therapy. The percentage of the left ventricular myocardium supplied by vessels with 70% or greater luminal stenosis was the most significant variable in influencing failure of medical therapy defined as sudden death, myocardial infarction, or need for bypass surgery. Whether or not the patient received nifedipine was the second most powerful variable, with the use of nifedipine reducing by half the relative risk of failing medical therapy. These were followed by cigarette smoking and presence of global ST segment changes during ischemia. After 18 months the nifedipine group had fewer patients failing medical therapy (p = .02), with fewer patients undergoing coronary bypass surgery (p less than .01). However, nifedipine did not appear to have a preventive effect against myocardial infarction or death. Kaplan-Meier actuarial curves confirmed that medical therapy was significantly less successful in the presence of increasing numbers of significantly stenotic vessels (p = .03). However, nifedipine provided a significant beneficial effect in patients with two or more stenotic vessels (p less than .01) and in whom 50% or more of the myocardium was supplied by vessels with 70% or greater stenosis (p = .01). Thus, although patients with advanced obstructive coronary disease have the greatest likelihood of unfavorable outcomes, the addition of nifedipine is of significant benefit.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
143.
Although Helicobacter pylori have been identified in the liver, the role of Helicobacter sp. in human liver diseases remains unclear. This study explored whether H. pylori were internalized and could persist in hepatocytes. The majority of an inoculum of H. pylori (1 x 10(7) colony forming units) adhered to hepatocytes. Using the gentamicin invasion assay we found that approximately 2% were internalized and persisted following passage for more than 2 months. Electron microscopy confirmed the presence of intracellular Helicobacter. The number of adherent or internalized H. pylori was significantly greater with hepatocytes than with gastric epithelial cells (P < 0.05) and was also dependent on cag pathogenicity island (PAI), VacA, OipA, or BabA status. Transmission electron microscopy was used to confirm adherence and invasion of H. pylori into hepatocytes. Internalization of H. pylori was inhibited by antibodies to beta1-integrin receptors, genistein, and cytochalasin D (P < 0.05) consistent with beta1-integrin acting as a surface receptor with additional requirements for tyrosine kinase phosphorylation and actin polymerization. In summary, H. pylori both adhered to and invaded into hepatocytes in vitro, depending on the virulent factors, and persisted within hepatocytes during subcultures. beta1-integrin is likely a receptor involved in internalization of H. pylori into hepatocytes.  相似文献   
144.
145.
目的 探讨玻璃化冷冻胚胎移植(FET)和新鲜胚胎移植(NET)的临床结局。方法回顾性分析2013年1月至2014年3月在中山大学孙逸仙纪念医院行体外受精-新鲜胚胎移植(IVF-NET)577个周期及单精子卵细胞浆内显微注射-新鲜胚胎移植(ICSI-NET)118个周期、FET 175个周期共870个周期的临床资料,比较NET组和FET组(曾经NET未成功妊娠,后行FET者)的临床特征和助孕结局,再将FET组分为妊娠亚组和未妊娠亚组进一步分析比较。采用二分类logistic回归分析影响妊娠结局的因素。结果 FET组的种植率(26.27% vs. 31.98%,P=0.01)、临床妊娠率(47.43% vs. 65.18%,P<0.001)均明显低于NET组,差异均有统计学意义;FET组的流产率(P=0.63)、生化妊娠率(P=0.17)和胎儿出生体重(P=0.33)与NET组相比差异均无统计学意义。FET组中妊娠亚组与未妊娠亚组女方年龄(30.69岁±3.37岁 vs. 32.00岁±5.09岁,P=0.03)的差异有统计学意义;BMI、不孕年限、基础内分泌等指标的差异均无统计学意义。二分类logistic回归分析显示是否行FET(P<0.001)、女方年龄(P<0.001)、BMI(P=0.011)和优质胚胎数(P<0.001)为影响妊娠结局的因素。结论 曾经行NET未成功的妊娠者,随后使用FET者其种植率和妊娠率均较低,但不增加流产率,未影响胎儿出生体重,未发现FET对妊娠结局有不良影响。  相似文献   
146.
目的 探讨成年居民膳食胆固醇摄入与高胆固醇血症的关系. 方法 利用“中国健康与营养调查”数据,本研究中纳入的研究对象为同时参加2004年和2009年2轮调查、且在2009年调查时年龄为25~65岁、血样检测和膳食调查数据完整的成年居民,共4 244人.以《中国成人血脂异常防治指南2007》为标准,血清TC≥6.22 mmol/L时,判定为高胆固醇血症.采用非条件logistic回归方法,研究膳食胆固醇摄入与高胆固醇血症的关系.结果 2009年成年居民平均血清TC水平为4.9 mmol/L,高胆固醇血症患病率为9.6%.2004-2009年膳食胆固醇摄入量总体呈大幅增长,尤其是低摄入量组的增幅最大.男性成年居民中2004年膳食胆固醇摄入中低水平者和2009年膳食胆固醇摄入高水平者,高胆固醇血症患病风险增加.女性膳食胆固醇摄入与高胆固醇血症之间未见统计学关联.结论 膳食胆固醇摄入与高胆固醇血症的关系具有性别差异.膳食胆固醇摄入水平升高,可增加男性居民发生高胆固醇血症的危险性.  相似文献   
147.
目的:分析讨论多层螺旋CT血管成像(CTA)对原发性蛛网膜下腔出血(SAH)患者的诊断价值及动态血清S‐100B蛋白检测SAH患者脑损害程度及脑血管痉挛的评价作用。方法对166例SAH患者行CTA检查,抽取患者入院后1、2、3、7d时的肘静脉血检测血清S‐100B蛋白水平。结果166例SAH患者中,CTA共检出119处动脉瘤。Hunt‐HessⅠ~Ⅱ级患者入院后1dS‐100B蛋白水平为(0.71±0.11)μg/L,7d为(0.62±0.09)μg/L,Hunt‐HessⅣ级的患者入院后1dS‐100B蛋白水平为(2.12±0.23)μg/L,7d为(1.97±0.06)μg/L,S‐100B蛋白水平与Hunt‐Hess分级呈正比。格拉斯哥昏迷(GCS)评分3~8分的患者入院后1dS‐100B蛋白水平为(1.87±0.23)μg/L,7d为(1.87±0.23)μg/L。GCS评分13~15分的患者入院后1dS‐100B蛋白水平为(0.63±0.17)μg/L,7d为(0.44±0.15)μg/L,GCS评分越低,S‐100B蛋白水平越高。结论CTA可显示血管的空间立体结构及周边关系,有助于治疗方法的选择和难度的评估。检测血清中S‐100B蛋白浓度能评估继发性脑损害的严重情况和脑血管痉挛的可能性。  相似文献   
148.

Purpose

To determine whether erythromycin is non-inferior to metoclopramide in facilitating post-pyloric placement of self-propelled spiral nasoenteric tubes (NETs) in critically ill patients.

Methods

A prospective, multicenter, open-label, parallel, and non-inferiority randomized controlled trial was conducted comparing erythromycin with metoclopramide in facilitating post-pyloric placement of spiral NETs in critically ill patients admitted to intensive care units (ICUs) of eight tertiary hospitals in China. The primary outcome was procedure success defined as post-pyloric placement (spiral NETs reached the first portion of the duodenum or beyond confirmed by abdominal radiography 24 h after tube insertion).

Results

A total of 5688 patients were admitted to the ICUs. Of these, in 355 patients there was a plan to insert a nasoenteric feeding tube, of whom 332 were randomized, with 167 patients assigned to the erythromycin group and 165 patients assigned to the metoclopramide group. The success rate of post-pyloric placement was 57.5% (96/167) in the erythromycin group, as compared with 50.3% (83/165) in the metoclopramide group (a difference of 7.2%, 95% CI ??3.5% to 17.9%), in the intention-to-treat analysis, not including the prespecified margin of ??10% for non-inferiority. The success rates of post-D1 (reaching the second portion of the duodenum or beyond), post-D2 (reaching the third portion of the duodenum or beyond), post-D3 (reaching the fourth portion of the duodenum or beyond), and proximal jejunum placement and the incidence of any adverse events were not significantly different between the groups.

Conclusions

Erythromycin is non-inferior to metoclopramide in facilitating post-pyloric placement of spiral NETs in critically ill patients. The success rates of post-D1, post-D2, post-D3, and proximal jejunum placement were not significantly different.
  相似文献   
149.
目的:采用Jensen直肌联结术联合麻痹肌的拮抗肌后徙术和超大量麻痹肌缩短联合超大量麻痹肌的对抗肌后徙术两种手术方法治疗麻痹性水平斜视,观察两种手术方法的治疗效果及临床意义。
  方法:回顾性分析我院自2005-01/2014-08收治完全性或近完全性水平直肌麻痹斜视患者15例17眼,分别采用Jensen直肌联结术联合麻痹肌的拮抗肌后徙术治疗A组7例7眼,超大量麻痹肌缩短联合超大量麻痹肌的对抗肌后徙术治疗B组8例10眼,术后随访平均21±8.71 mo观察手术疗效。
  结果:术后观察患者15例17眼均获得满意效果,14例16眼患者术后随访获得较为理想的远期效果。1例1眼患者术后6 mo随访斜视度30?。远/近斜视度数明显降低( t=28.71,P<0.001;t=36.21,P<0.001),双眼固视视野范围扩大(t=17.96,P<0.001)、麻痹肌运动程度提高等视觉功能均有不同程度改善(t=9.20,P<0.001)。
  结论:采取Jensen直肌联结术联合麻痹肌的拮抗肌后徙术和超大量麻痹肌缩短联合超大量麻痹肌的对抗肌后徙术治疗完全性或近完全性麻痹性水平斜视,手术方法安全可靠,患者能获得眼位正位、麻痹肌运动改善、双眼固视视野扩大的长期稳定效果。  相似文献   
150.
The piezoelectric and elastic properties of a molecular piezoelectric meta-nitroaniline (mNA) in its single-crystal form were investigated in the framework of first-principles density functional perturbation theory (DFPT). Results support the recent experimental findings those despite being soft and flexible, mNA''s piezoelectric coefficients are an order of magnitude greater than that of ZnO and LiNbO3. A molecular-level insight into the piezoelectric properties of mNA is provided. These results are helpful not only for better understanding mNA, but also for developing new piezoelectric materials.

The piezoelectric and elastic properties of a molecular piezoelectric meta-nitroaniline (mNA) in its single-crystal form were investigated in the framework of first-principles density functional perturbation theory (DFPT).  相似文献   
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