首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   16836篇
  免费   1508篇
  国内免费   48篇
耳鼻咽喉   257篇
儿科学   505篇
妇产科学   341篇
基础医学   2633篇
口腔科学   372篇
临床医学   1697篇
内科学   3375篇
皮肤病学   291篇
神经病学   1691篇
特种医学   520篇
外科学   2438篇
综合类   326篇
一般理论   16篇
预防医学   1478篇
眼科学   357篇
药学   1112篇
中国医学   22篇
肿瘤学   961篇
  2021年   257篇
  2020年   148篇
  2019年   248篇
  2018年   278篇
  2017年   193篇
  2016年   228篇
  2015年   263篇
  2014年   425篇
  2013年   667篇
  2012年   903篇
  2011年   918篇
  2010年   568篇
  2009年   456篇
  2008年   917篇
  2007年   927篇
  2006年   931篇
  2005年   964篇
  2004年   955篇
  2003年   929篇
  2002年   879篇
  2001年   236篇
  2000年   201篇
  1999年   244篇
  1998年   223篇
  1997年   189篇
  1996年   190篇
  1995年   191篇
  1994年   182篇
  1993年   160篇
  1992年   247篇
  1991年   194篇
  1990年   193篇
  1989年   203篇
  1988年   198篇
  1987年   152篇
  1986年   205篇
  1985年   210篇
  1984年   207篇
  1983年   196篇
  1982年   187篇
  1981年   206篇
  1980年   179篇
  1979年   125篇
  1978年   177篇
  1977年   125篇
  1976年   143篇
  1975年   139篇
  1974年   114篇
  1973年   123篇
  1972年   89篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
A gastrostomy was fashioned laparoscopically in a 15 year old patient with a severe head injury. A preceding attempt at percutaneous endoscopic gastrostomy had failed. The gastrostomy tube was inserted into the stomach under vision and the stomach attached to the anterior abdominal wall by sutures.  相似文献   
92.
93.
94.
The purpose of this study is to evaluate the effectiveness of a shorter course of Dialectical Behavior Therapy (DBT) in enhancing treatment retention and reducing: urges to engage in non-suicidal self injury (NSSI), NSSI, suicide ideation, and subjective distress in borderline personality disorder (BPD). Twenty patients with BPD received a six-month course of Dialectical Behavior Therapy (DBT-B). DBT-B was delivered in the standard manner except for the shortened duration from one-year minimum to six months. All variables were measured at baseline, and at six months. Data were analyzed using paired t-tests. Treatment retention rate was 95%. Significant reductions were found in NSSI urges, NSSI, suicide ideation, subjective distress, depression, and hopelessness between baseline and six months. These results support the use of DBT-B in a six-month format when NSSI and suicidal behavior and ideation are the targeted behaviors. Target behaviors were reduced significantly and retention was extremely high in comparison to other interventions for this population. A large scale randomized controlled trial investigating its efficacy is warranted to determine if the results can be replicated and if improvement can be sustained.  相似文献   
95.
This article presents the revision process, major innovations, and clinimetric testing program for the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (UPDRS), known as the MDS-UPDRS. The UPDRS is the most widely used scale for the clinical study of Parkinson's disease (PD). The MDS previously organized a critique of the UPDRS, which cited many strengths, but recommended revision of the scale to accommodate new advances and to resolve problematic areas. An MDS-UPDRS committee prepared the revision using the recommendations of the published critique of the scale. Subcommittees developed new material that was reviewed by the entire committee. A 1-day face-to-face committee meeting was organized to resolve areas of debate and to arrive at a working draft ready for clinimetric testing. The MDS-UPDRS retains the UPDRS structure of four parts with a total summed score, but the parts have been modified to provide a section that integrates nonmotor elements of PD: I, Nonmotor Experiences of Daily Living; II, Motor Experiences of Daily Living; III, Motor Examination; and IV, Motor Complications. All items have five response options with uniform anchors of 0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe. Several questions in Part I and all of Part II are written as a patient/caregiver questionnaire, so that the total rater time should remain approximately 30 minutes. Detailed instructions for testing and data acquisition accompany the MDS-UPDRS in order to increase uniform usage. Multiple language editions are planned. A three-part clinimetric program will provide testing of reliability, validity, and responsiveness to interventions. Although the MDS-UPDRS will not be published until it has successfully passed clinimetric testing, explanation of the process, key changes, and clinimetric programs allow clinicians and researchers to understand and participate in the revision process.  相似文献   
96.
Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives.  相似文献   
97.
98.
OBJECTIVE: The recent development of fetal ultrasonography has allowed for an increasing number of prenatal diagnoses for congenital cystic adenomatoid malformation (CCAM). However, the appropriate surgical timing of these patients has not been studied as of yet. The aim of this study is to suggest a safe strategy for the treatment of CCAM by identifying the relationship between the timing of surgery and postoperative outcome. METHODS: Between 1987 and 2003, 40 patients (28 males, 12 females) underwent surgical resection for CCAM. The mean age was 38.6+/-9.1 (2 days-13 years) months. CCAM was diagnosed by prenatal ultrasonography in eight patients. Early operations were performed in four out of the eight. Operation was deferred until 2-12 months of age for the remaining four patients. RESULTS: Type I CCAM was found in 20 patients, type II in 20 and no patient exhibited type III. Five patients had associated pectus excavatum anomaly. There were no cases of operative mortality. Seventeen minor postoperative complications developed in 16 patients (40.0%): prolonged chest tube drain in 10, wound infection in 4, and 1 case of pneumonia, empyema and pleural space, respectively. The average hospital stay was 11.8 (6-29) days. During the mean follow-up period of 67.5 months, one patient died of accidental aspiration 7 months after operation during the postoperative recovery course of Ravich operation for pectus excavatum. The remaining patients reported doing well with normal physical activity. All five patients who underwent surgery at the age of under 1 month did not exhibit increased postoperative morbidity. CONCLUSIONS: We concluded that surgery for CCAM could be safely performed in all age groups with satisfactory long-term outcomes. It is suggested that early elective surgical correction can be recommended for a patient whose diagnosis was made in utero.  相似文献   
99.
100.
Epithelial coverage of a laryngotracheal wound is an important factor in preventing stenosis, and endoscopic transplantation of a free mucosal graft without stents or sutures would be a significant therapeutic advance. In vitro and in vivo canine studies were performed to explore the feasibility of transplantation with a low-power diode laser (400 mW) enhanced by indocyanine green dye-doped albumin. The tensile strength of graft adherence in 10 cadaver larynges was strong (35.25 ± 10.39 g). Survival studies in live canine models with a specially designed endoscopic instrument set showed excellent healing at 6, 14, and 28 days. Healing was documented with photography and by histologic examination. Successful endoscopic transplantation of a free mucosal graft should improve results of treatment for laryngotracheal stenosis and laryngeal reconstructive surgery.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号