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Hypospadias and urethral development   总被引:16,自引:0,他引:16  
PURPOSE: Hypospadias is a common congenital anomaly that may be treated with surgical reconstruction. In the majority of cases the etiology remains elusive. Although androgens are clearly critical for penile development, defects in androgen metabolism and/or the androgen receptor explain only a small subset of cases of hypospadias. Strategies are presented for understanding the etiology of hypospadias. MATERIALS AND METHODS: Current scientific reports on the etiology of hypospadias were reviewed, and the embryology and possible mechanisms of urethral and penile formation are presented. RESULTS: A new theory of glandular human urethral development via endodermal cellular differentiation is proposed to replace the classic explanation of ectodermal intrusion. CONCLUSIONS: Careful studies of penile and urethral development have led to a better understanding of genital embryology. Future areas of study, such as endocrine disrupters, mesenchymal-epithelial interactions and mechanisms of penile growth, are proposed to explain the etiology of hypospadias.  相似文献   
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PURPOSE: We analyze a group of patients who presented with mechanical dysfunction of the reservoir and/or efferent limb of a continent colonic urinary diversion, and establish an evaluation and management algorithm. MATERIALS AND METHODS: A total of 16 patients with a mean age of 58 years and 1 or more symptoms related to continent colonic urinary diversion were evaluated. Presenting symptomatology included difficult catheterization in 8 cases (50%), disabling incontinence in 8 (50%) and recurrent urinary tract infections in 6 (37.5%). All patients had normal, nonobstructed, nonrefluxing upper tracts and none presented with stone disease. Urological evaluation consisted of catheterization, fluoroscopy and urography of the pouch, retrograde urography of the external limb and urodynamics (enterocystometrogram and outlet pressure profilometry). RESULTS: Of the 8 patients with difficulty with catheterization 4 had stomal stenosis, 2 had an elongated and redundant external limb, and 2 had a false passage. Diagnosis was established by the inability to catheterize, fluoroscopy of the pouch and retrograde urography. Disabling incontinence occurred in 8 patients, including 7 who presented with an incompetent outlet and 2 with high pressure intestinal contractions of the reservoir. The aforementioned abnormalities were diagnosed by a combination of retrograde urography, urography of the pouch and urodynamics. Recurrent symptomatic urinary infections were observed in 5 patients of the previous groups and in another with an hourglass reservoir, which was primarily diagnosed by urography of the pouch. Surgical correction in 15 patients included outlet reinforcement, reservoir revision, stomal or external limb revision and conversion to a urinary conduit. Surgical treatment was successful in 14 of 15 patients (93%). CONCLUSIONS: Catheterization difficulty requires retrograde urography to define possible anatomical abnormalities (false passage, conduit elongation) if catheterization and fluoroscopy of the pouch do not demonstrate stomal stenosis. Urinary incontinence benefits from enterocystometry and outlet pressure measurement to determine reservoir and external limb function. Recurrent urinary tract infections not related to ureteral obstruction or reflux requires fluoroscopy of the pouch and external limb to determine abnormalities in patients with detubularization and localization of areas of urine pooling.  相似文献   
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PURPOSE: We performed a prospective study to determine the incidence and spectrum of metabolic abnormalities predisposing to stone formation in patients with ureteropelvic junction obstruction and renal calculi. MATERIALS AND METHODS: A total of 47 consecutive patients with congenital ureteropelvic junction obstruction underwent metabolic evaluation of stone risk factors. Of these patients 21 had associated stones (study group), while 26 did not (control group). Logistical regression, Wilcoxon rank sum and Fisher's exact tests were performed to determine whether there was a significant difference between these groups in regard to the presence of metabolic risk factors. RESULTS: Demographically and symptomatically the 2 groups were equivalent except that the study patients were older. The 24-hour urinary excretion of calcium was significantly higher in study than in the control patients (p = 0.007). While the incidence of hypercalciuria and hyperuricosuria was also higher in the study population, these differences were not significant (p = 0.08 and 0.07, respectively). CONCLUSIONS: Metabolic abnormalities predisposing to stone formation are present more frequently in patients with ureteropelvic junction obstruction who have associated stones compared to those who do not. As such, urinary stasis alone does not explain stone formation in these cases. Rather, the local physiological environment of urine likely has a predisposing role. In addition to restoring unobstructed urinary flow, consideration should be given to metabolic evaluation and prophylactic treatment for affected patients.  相似文献   
46.
目的 分析医院Ⅰ类切口手术抗菌药物预防性使用情况,加强Ⅰ类切口手术抗菌药物预防使用的控制和管理.方法 通过医院信息系统(HIS)统计2018年1-11月江苏省盐城市第一人民医院Ⅰ类切口手术数量和抗菌药物使用率,筛选出冠脉造影等血管介入诊断手术和重点监控Ⅰ类切口手术,统计其抗菌药物使用率,再通过电子信息化病历系统分析抗菌...  相似文献   
47.
按照文献检索的方法,通过万方数据知识服务平台搜集相关文献,提取符合标准的相关基本信息,按照年度变化、医疗机构、期刊分布、作者情况等进行统计分析,从而了解无锡地区医疗机构2009-2013年间在中华系列核心期刊上发表论文数量动态变化,为医院科研管理部门提供决策参考。  相似文献   
48.
高血压作为全球高发的疾病,是许多心脑血管疾病的主要危险因素,给社会带来巨大的经济负担。近年来,焦虑障碍和抑郁障碍的发病率逐年上升,高血压共病焦虑抑郁的人数也在不断增加,现有的研究表明两者可能存在相互促进的关系,在发病机制上也有一定共通性,但两者共病的机制尚未完全阐明。本文就原发性高血压伴焦虑抑郁障碍的定义及诊断量表、流行病学、相互影响机制和治疗等展开综述。  相似文献   
49.
目的 应用冠状动脉计算机断层扫描血管成像(CCTA)斑块定量分析,比较急性冠脉综合征(ACS)和稳定性冠心病(SCAD)患者冠状动脉斑块成分与负荷特征。方法 回顾性纳入2021年1月至3月就诊于中国人民解放军总医院第一医学中心心血管内科的116例冠心病(CAD)患者的临床资料,根据患者临床诊断结果将其分为ACS组(81例)和SCAD组(35例)。2组患者均在14 d内先后接受CCTA和冠状动脉造影检查。采用CCTA斑块定量分析软件测量各类斑块成分体积及负荷、最小管腔直径和重构指数(RI)、偏心指数(EI)等影像学指标并比较分析。采用SPSS 20.0软件进行数据分析。根据数据类型,组间比较分别采用t检验、Wilcoxon检验及χ2检验。结果 ACS组患者较SCAD组患者具有更大的总斑块负荷(TPB)、非钙化成分负荷(NCPB)和脂质成分负荷(LPB),差异均有统计学意义[(60.5±11.2)%和(51.7±14.4)%,(58.9±12.0)%和(50.1±15.2)%,17.9%(11.6%,27.6%)和14.2%(7.5%,20.8%),均P<0.0...  相似文献   
50.
Unit managers do need formal supervisory training. Training should focus on their approach to the decision making process as wel as their performance within it. Quality circle training was deemed most appropriate, because it focuses on team management and the development of skills needed to handle interactions in team settings.  相似文献   
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