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   20312篇
  免费   1565篇
  国内免费   647篇
耳鼻咽喉   173篇
儿科学   348篇
妇产科学   562篇
基础医学   2615篇
口腔科学   419篇
临床医学   2283篇
内科学   4244篇
皮肤病学   256篇
神经病学   1198篇
特种医学   753篇
外国民族医学   3篇
外科学   2663篇
综合类   1503篇
现状与发展   3篇
一般理论   5篇
预防医学   1099篇
眼科学   746篇
药学   1661篇
  6篇
中国医学   570篇
肿瘤学   1414篇
  2024年   35篇
  2023年   228篇
  2022年   460篇
  2021年   691篇
  2020年   454篇
  2019年   490篇
  2018年   574篇
  2017年   509篇
  2016年   500篇
  2015年   673篇
  2014年   814篇
  2013年   939篇
  2012年   1400篇
  2011年   1494篇
  2010年   905篇
  2009年   750篇
  2008年   1101篇
  2007年   1154篇
  2006年   1144篇
  2005年   1133篇
  2004年   925篇
  2003年   798篇
  2002年   780篇
  2001年   553篇
  2000年   542篇
  1999年   500篇
  1998年   253篇
  1997年   264篇
  1996年   209篇
  1995年   175篇
  1994年   146篇
  1993年   111篇
  1992年   222篇
  1991年   205篇
  1990年   178篇
  1989年   180篇
  1988年   150篇
  1987年   135篇
  1986年   117篇
  1985年   105篇
  1984年   61篇
  1983年   43篇
  1982年   70篇
  1981年   53篇
  1980年   59篇
  1979年   40篇
  1978年   36篇
  1977年   33篇
  1976年   25篇
  1975年   29篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
  相似文献   
12.
13.
14.
15.
Epiphrenic diverticulum is rare, comprising of about 10% of all esophageal diverticula. Carcinoma arising within such a diverticulum is even less common. We report on two patients with squamous cell carcinoma arising from an epiphrenic diverticulum. Some features of malignant change related to the epiphrenic diverticula were misdiagnosed or missed in our cases and other reports due to lack of clinical experience. It is important to exclude the possibility of malignancy as this is vital for surgical planning. Although the prognosis for patients with malignancy arising from an epiphrenic diverticulum is generally poor, a high index of suspicion may increase the chance of cure.  相似文献   
16.
咬肌与颅面形态的关系   总被引:3,自引:0,他引:3  
目的探讨咬肌与颅面形态之间的关系,了解咬肌体积与邻近骨骼结构的大小及形态的相关性。方法对40例要求改变脸型者进行磁共振成像(MRI)测量,人体测量,头部正位、侧位和下颌骨曲面断层X线检查,测量并计算咬肌体积(MsV),测量头长(HL)、头宽(HB)、面长(FL)、面宽(FB)、下颌角间宽(IB)、下颌骨体长(CL)、下颌角切线长(MAL)、下颌角角度(JA),计算颜面形态指数FI(FL/FB)、头颅指数C(IHB/HL)。用SPSS11.5软件统计分析MsV与HI。HB、FL、FB、IB、CL、MAL、JA、FI、CI之间的相关性。结果MsV与JA呈明显负相关,与CL、MAL、IB、FB、HL呈明显正相关,与CL、FI、HB无明显相关性。结论咬肌肥大可能是方脸面型的成因之一,是影响面型的重要因素。  相似文献   
17.
Three patients who presented with scrotal swelling within a few days of inguinal herniorrhaphy are reported. Ultrasonography scans performed in these patients all demonstrated features suspicious of recurrence of hernia. One patient underwent surgical exploration, which revealed only a scrotal haematoma without evidence of recurrent hernia. The other two patients were managed conservatively because clinically the swellings were regarded to be more compatible with haematoma. Both patients had subsequent resolution of the scrotal swelling with no clinical evidence of recurrence of hernia on follow‐up. It is concluded that sonographic diagnosis of recurrence of hernia shortly after inguinal herniorrhaphy can occasionally be misleading.  相似文献   
18.
After measurement of normal renal function, dog kidneys (n = 52) were subjected to 3, 15, or 30 min of normothermic warm ischemia (WI). After 24 hr of preservation by simple hypothermic storage (SHS) in a modified Collins solution, autotransplant was done and renal function was again measured beginning at 1 hr. Compared with preharvest values, kidneys with minimal (3 min) WI had significantly decreased clearances of creatinine (Cr) and para-aminohippuric acid (PAH), PAH extraction, absolute and fractional Na reabsorption, Na excretion, and urinary Na concentration; no change in urine flow rate or K excretion; and significantly increased fractional excretion of Na, K, and H2O. Compared with minimal WI, 30-min WI produced further significant decreases in clearances of Cr, PAH, and PAH extraction; and further increases in fractional excretion of Na, K, and H2O. Urine flow was also decreased by about half and urine Na concentration rose significantly. Several parameters were very significantly correlated with the length of WI, but the most reliable index was the fractional reabsorption of Na. When several functional parameters were used together, kidneys with significant (30 min) WI prior to preservation could be identified with a high degree of statistical reliability.  相似文献   
19.
Mingying  Lai  Ningli  Wang 《眼科学报》1997,13(3):116-119
Purpose : To compare the clinical application value of Ultrasound biomicrsocpic dark room provocative test with the traditional dark room test in screening primary angle closure glaucoma (PACG).Methods: 22 eyes with PACG in prodromal stage and 30 eyes with deep anterior chamber and wide angle of 15 normal persons were observed in this trail. All 52 eyes were performed traditional dark room provocative test and ultrasound biomicorosopic darkroom test respectively. With different positive diagnostic criteria, the sensitivity of the two methods were compared using chi-squared analysis.Results : After staying in the dark room for 2 hours, In case group, IOP in 10 of 22 eyes rose more than 1. 07kPa(1kPa = 7.5mmHg), in 12 eyes less than 1.07kPa or had no changes; appositional angle closure were found by Goldmann gonioscopy in 8 eyes : 3 eyes in two quadrants, 5 eyes in more than two quadrants; the appositional angle closure was found by UBM in 15 eyes; 3 eyes in one quadrants, 5 eyes in two quadrants, 7 eyes  相似文献   
20.
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