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41.
Syndrome X in women is associated with oestrogen deficiency   总被引:3,自引:1,他引:2  
This study was undertaken to ascertain whether gynaecologicalhistory or a reduction in ovarian hormones are triggers of anginain menopausal women with a positive exercise test and normalcoronary arteries. The majority of patients with angina pectoris,a positive exercise test and normal coronary arteries are female,suggesting that the female gender may be important in the aetiology.We studied the gynaecological features of 107 women (age 53±9 years) with syndrome X, taken from a population of134 patients including 27 males. Cardiological investigationswere undertaken and detailed gynaecological history obtainedfrom all the female patients. Menopausal status was confirmedby plasma levels of oestradiol-17ß100 pmol. l–1. In 95 of the 107 female patients, chest pain began either duringthe perimenopausal period (32) or after the menopause (63).Of the 63 menopausal patients, 43 had undergone hysterectomyat an average of 8 ± 6 years prior to the onset of chestpain. The incidence of hysterectomy in the study population(40%) was four times greater than that of an age-matched population.These findings confirm that the majority of patients with syndromeX are women in whom the chest pain began after the onset ofmenopause. Ovarian hormone deficiency may, therefore, play arole in the onset of syndrome X in female patients.  相似文献   
42.
对不用贴附基质和生长因子情况下原代培养72h的人脐动脉内皮细胞(HUAEC)进行了透射电镜观察。电镜下HUAEC形态不规则,细胞器丰富。核周有散在的滑面内质网、粗面内质网及较多的线粒体,后者有些为板层状嵴,另一些为管泡状嵴。细胞膜下可见微管,胞质内有大量循同一方向排列的微丝。Weibel Palade小体内含涡旋状排列的细管。胞质内含丰富的糖原颗粒。细胞核内常染色质较多,异染色质主要分布于核膜下。有时可见处于无丝分裂状态的细胞,核已分裂为二,但二者间仍有核膜相连。内皮细胞间以紧密连接或中间连接的方式相连。以上结果表明:人脐动脉内皮细胞在体外培养条件下代谢功能旺盛,且具有参与脂类代谢的细胞器,细胞以无丝分裂方式增殖。  相似文献   
43.
去窦弓神经大鼠的心血管及肾脏的形态学改变(英文)   总被引:1,自引:0,他引:1  
目的 研究去窦弓神经 (SAD)对正常血压大鼠的血流动力学及心、肾、血管等器官病理形态学的影响。方法 采用SD大鼠施行SAD手术 ,术后 18周行股动脉插管 ,在清醒、自由活动状态下计算机实时记录 2 4h动脉收缩压、舒张压和心率 ,并计算血压波动性 (BPV)和心率波动性 (HRV)。处死动物后 ,取心、脑、肾及脾观察大体及光学显微镜下结构变化。结果 SAD术后 18周 ,SAD大鼠的血压和心率水平与假手术组相比无显著差异 ,但 2 4hBPV明显高于假手术组 ,HRV明显低于假手术组 ;大鼠心、肾及血管有明显的类似于高血压靶器官损伤的病理改变。结论 SAD可使大鼠的心、肾和血管发生类似于高血压靶器官损伤的病理改变。  相似文献   
44.
米非司酮用于足月妊娠引产时脐动脉血流的测定   总被引:11,自引:1,他引:11  
目的:评价米非司酮用于足月妊娠引产时对胎盘血液供应的影响。方法:将97例妊娠38~42周具有引产指征的孕妇随机分为两组:治疗组(49例)给予口服米非司酮,每次50mg12小时1次连续2天后,阴道置米索前列醇25μg,12小时1次;对照组(48例)予静脉推注蒂洛安200mg,每日1次连续3天后,静脉点滴催产素引产。两组孕妇均在用药前及用药后36~48小时行脐动脉血流速度测定,以收缩期血流速度峰值(S)与舒张末期血流速度峰值(D)的比值(S/D)为测定参数,观察用药前及用药后36~48小时的脐血流S/D值的改变。结果:两组用药前及用药后36~48小时的脐血流S/D值比较,差异无显著性(P>0.05)。结论:米非司酮50mg12小时1次连续2天口服用于足月妊娠引产不仅效果良好,且对胎盘血流动力学无显著影响。  相似文献   
45.
恶性肿瘤累及颈动脉的外科处理   总被引:2,自引:1,他引:2  
为探讨头颈部恶性肿瘤侵犯颈动脉的外科治疗,对5例喉癌或下咽癌颈淋巴结转移累及一侧颈动脉病人,术前经CT或B超检查,3例经术前体外颈动脉压迫训练合格后手术切除受累段颈总动脉,2例系术中损伤颈总动脉后紧急切除受轻动脉。其中1例即刻行断端吻合,5例术中,术后均无明显脑缺血表现,3例术后随访2年以上健在,2例尚在随访中。  相似文献   
46.
To determine the effects of animal and artificial surfactants on cerebral haemodynamics, 20 premature babies receiving mechanical ventilation were randomized to receive Curosurf or Exosurf surfactant. Anterior cerebral artery blood flow velocity (CABFV) was measured using Doppler ultrasound before and up to 2 h after treatment. Following animal surfactant there was a rapid reduction in CABFV (median -36%, range -43% to +8%, p < 0:01), whereas artificial surfactant resulted in a slower rise which was less marked (median +20%, range -7% to +62%, p < 0:05). There were no significant changes in blood pressure. Two hours after administration, the oxygenation index (OI) improved significantly only in babies receiving animal surfactant. In this group there was a significant association between the change in CABFV at 1 min and the change in OI at 2 h ( r = 0:66, p < 0:05). Animal surfactant produces rapid improvements in ventilation which are associated with marked alterations in cerebral haemodynamics.  相似文献   
47.
A case of unusual longevity to the age of 58 years is reported for a female patient with complete transposition of the great arteries. The association with a wide atrial septal defect with intact interventricular septum may have contributed to the long survival without surgery. Factors determining intercirculatory mixing and systemic oxygen saturation may be the high pulmonary flow, the location of the anatomic communication, sufficient hemoglobin concentration to allow an adequate level of systemic resistance and recirculated systemic flow, and the belated development of pulmonary vascular disease.  相似文献   
48.
糖尿病患者下肢动脉管壁内膜-中层厚度的研究   总被引:4,自引:0,他引:4  
目的 研究糖尿病与动脉硬化性血管障碍的关系。方法 对60例糖尿病患者及60例非糖尿病患者进行超声检查,两侧下肢动脉内径(D)、内膜-中层厚度(IMT)、收缩期最高速度(Max)、舒张期速度(Min)、搏动指数(PI)、阻力指数(RI)及有无斑块形成,进行统计。结果 IMT糖尿病组较非糖尿病组增厚(P〈0.01),各项血流参数在糖尿 且与非糖尿病组间差别无显著性(P〈0.05)。结论 下肢动脉的IM  相似文献   
49.
The aim of this study was to determine long-term success of flexible tantalum stents for the treatment of ostial and truncal renal artery stenosis. Since 1989, flexible tantalum stents (type Strecker) were implanted in 34 patients (36 arteries, 25 ostial lesions, 11 truncal lesions) with uncontrollable renovascular hypertension, 9 of them in association with renal insufficiency. Stents were placed unilaterally in 32 patients, and bilaterally in 2 patients for the treatment of renal artery stenosis. Thirty-five of 36 lesions were atherosclerotic, including 5 recurrencies after previous percutaneous transluminal renal angioplasty (PTRA). One patient had Takayasu arteritis. Stents were implanted after unsuccessful PTRA of 11 truncal and 23 ostial lesions, and as a primary procedure in 2 ostial lesions. Follow-up examinations included blood pressure measurement, determination of serum creatinine level, color duplex sonography, or angiography. The technical success rate was 92 %. Technical failure included incorrect stent placement (1 of 36 lesions, 2.8 %), and stent dislocation (2 of 36 lesions, 5.6 %), and two stents were retrieved percutaneously. In one case of Takayasu arteritis, residual stenosis of 40 % was observed. After technically successful stent placement, 77 % of patients became normotensive with or without medication. In the remaining patients there was partial improvement with blood pressure between 140 and 180 mmHg. Renal function improved in 76 % of patients (completely in 3 of 8, 38 %; and partially in 3 of 8, 38 %). Primary patency rate including all stented lesions and initial technical failures was 82.4 % ± 6.8 (1 year) and 82.4 % ± 9.2 (3 years). After technically successful stent placement, patency rates were 89.9 ± 5.6 % (1 year), and 89.9 ± 7.6 % (3 years). For ostial lesions, primary patency rate was 87.9 ± 6.7 % (1 year) and 87.9 ± 9.2 % (3 years). Placement of flexible tantalum stents in renal arteries is technically demanding, especially in ostial lesions. Once placed successfully, stent patency rate is excellent. Received: 8 December 1999; Accepted: 23 February 2000  相似文献   
50.
BACKGROUND: It was the aim of this study to elucidate the influence of opioids on coronary vascular tone using the model of isolated porcine coronary artery segments. METHODs: We studied the effects of fentanyl (0.01, 0.1, 1.0 microg ml(-1)), alfentanil (0.1, 1.0, 10 microg ml(-1)), and sufentanil (0.01, 0.1, 1.0 microg ml(-1)) on the contractile response to three vasoconstrictors, acetylcholine, histamine and serotonin. RESULTS: Fentanyl (0.1, 1.0 microg x ml(-1)) dose-dependently attenuated the contractile response to acetylcholine, but not to histamine and serotonin. There were no differences in fentanyl's vasorelaxing potency between rings with intact and denuded endothelium. Alfentanil and sufentanil did not exert any significant influence on any of the vasoconstrictors tested. CONCLUSION: It is concluded that, in isolated porcine coronary artery rings, fentanyl at high concentrations has an attenuating effect on acetylcholine-induced contractions, which is independent of endothelial function, whereas alfentanil and sufentanil do not influence coronary vascular tone.  相似文献   
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