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   9209篇
  免费   444篇
  国内免费   40篇
耳鼻咽喉   107篇
儿科学   226篇
妇产科学   89篇
基础医学   1138篇
口腔科学   306篇
临床医学   549篇
内科学   2242篇
皮肤病学   179篇
神经病学   682篇
特种医学   457篇
外科学   1695篇
综合类   30篇
预防医学   164篇
眼科学   133篇
药学   500篇
中国医学   17篇
肿瘤学   1179篇
  2023年   37篇
  2022年   32篇
  2021年   129篇
  2020年   70篇
  2019年   115篇
  2018年   172篇
  2017年   160篇
  2016年   186篇
  2015年   175篇
  2014年   259篇
  2013年   319篇
  2012年   520篇
  2011年   599篇
  2010年   342篇
  2009年   358篇
  2008年   554篇
  2007年   606篇
  2006年   619篇
  2005年   613篇
  2004年   644篇
  2003年   597篇
  2002年   579篇
  2001年   82篇
  2000年   88篇
  1999年   137篇
  1998年   167篇
  1997年   153篇
  1996年   152篇
  1995年   114篇
  1994年   120篇
  1993年   121篇
  1992年   64篇
  1991年   67篇
  1990年   64篇
  1989年   60篇
  1988年   53篇
  1987年   45篇
  1986年   47篇
  1985年   39篇
  1984年   51篇
  1983年   47篇
  1982年   47篇
  1981年   42篇
  1980年   35篇
  1979年   21篇
  1978年   29篇
  1977年   18篇
  1976年   16篇
  1974年   17篇
  1973年   15篇
排序方式: 共有9693条查询结果,搜索用时 265 毫秒
1.
2.
3.
We studied the trigeminal and facial motor nuclei of the hagfish by the retrograde HRP method. We distinguished 4 components in a single column of the motor nuclei of the trigeminal nerve and the facial nerve, viz., the pars magnocellularis of the trigeminal motor nucleus (mVm), the anterior part of the pars parvocellularis of the trigeminal motor nucleus (mVp1), the posterior part of the pars parvocellularis of the trigeminal motor nucleus (mVp2) and the facial motor nucleus (mVII). Although in Nissl preparations only the mVm could be distinguished from the rest of the nucleus, the boundaries of the other 3 components were clearly demarcated in HRP preparations. Intramuscular injections into two representative antagonistic jaw muscles revealed that there was no apparent topological organization of the neurons pertaining to the opening and closing muscles in the mVm and mVp1, but both antagonistic muscles were innervated bilaterally. Although the hagfish does possess a cartilaginous jaw, the organization pattern of the motor nuclei of the jaw muscles seems to be the most primitive of all living vertebrates.  相似文献   
4.
A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography (PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant potential of esophageal submucosal tumors.  相似文献   
5.
Summary The resorption and excretion of glucose by living cells can be explained to be due to a property of the minute-body-forming proteid existing in the cells.Also in this property, there is no difference between virus proteid (vaccinia) and the normal minute-body-forming proteid having no virus action.  相似文献   
6.
7.
8.
It has been well documented that piriform sinus fistulae often cause suppurative thyroditis; however, when a piriform sinus fistula does not present this symptom, making a correct diagnosis is very difficult. We have experienced 11 cases of a piriform sinus fistula. The conventional operational approach was performed in the initial eight patients, among which there were four recurrences in two patients. Therefore, a new operational approach was introduced for the three most recent cases and one recurrent case. First, the existence of the internal orifice of the fistula is confirmed with a laryngoscope, after which a transverse incision on the neck is made and the abscess dissected. The side wall of the piriform sinus is then opened with the help of a laryngoscope and the bottom part of the mucosa of the sinus transected with the internal orifice of the fistula, after which the fistula is removed en bloc with the bottom part of the sinus and abscess cavity. Using this operation, we experienced no complications and there has been no recurrence so far.This paper was presented at the 23rd Annual Meeting of Pacific Association of Pediatric Surgeons, June 1990 in Kona, Hawaii.  相似文献   
9.
We report a case of groove pancreatitis (GP) associated with a true pancreatic cyst. An 81-year-old man who had suffered epigastric pain for 4 months was referred to Saisekai Kure Hospital. Computed tomography and endoscopic retrograde pancreatography showed a cystic lesion in the groove area of the pancreas. Serum amylase elevation and imaging findings suggested GP due to the cyst. Six weeks of medical treatment did not improve the clinical symptoms. Therefore, pancreatoduodenectomy was performed. Histologic examination revealed a true cyst with intraluminal necrosis, which produced a protein plug that obstructed the Santorini duct. The parenchyma surrounding the groove area showed marked fibrosis and inflammatory cell infiltration. GP due to true pancreatic cyst was diagnosed. Although GP is usually caused by overconsumption of alcohol, which leads to changes in the pancreatic juice and the ultimate blockage of pancreatic outflow, the histologic features in our patient suggest that true pancreatic cyst stands as a secondary cause of GP.  相似文献   
10.
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis.  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