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   22337篇
  免费   1090篇
  国内免费   160篇
耳鼻咽喉   227篇
儿科学   423篇
妇产科学   186篇
基础医学   2907篇
口腔科学   622篇
临床医学   1473篇
内科学   5851篇
皮肤病学   389篇
神经病学   1891篇
特种医学   886篇
外科学   3664篇
综合类   95篇
预防医学   667篇
眼科学   443篇
药学   1514篇
中国医学   72篇
肿瘤学   2277篇
  2023年   116篇
  2022年   207篇
  2021年   469篇
  2020年   234篇
  2019年   379篇
  2018年   470篇
  2017年   386篇
  2016年   473篇
  2015年   480篇
  2014年   612篇
  2013年   772篇
  2012年   1277篇
  2011年   1458篇
  2010年   785篇
  2009年   665篇
  2008年   1283篇
  2007年   1417篇
  2006年   1352篇
  2005年   1488篇
  2004年   1419篇
  2003年   1416篇
  2002年   1351篇
  2001年   359篇
  2000年   315篇
  1999年   380篇
  1998年   316篇
  1997年   263篇
  1996年   198篇
  1995年   215篇
  1994年   182篇
  1993年   166篇
  1992年   220篇
  1991年   214篇
  1990年   191篇
  1989年   206篇
  1988年   204篇
  1987年   203篇
  1986年   185篇
  1985年   158篇
  1984年   134篇
  1983年   93篇
  1982年   62篇
  1981年   72篇
  1980年   59篇
  1979年   73篇
  1978年   54篇
  1977年   53篇
  1975年   52篇
  1971年   53篇
  1969年   49篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Objectives To develop a simple image viewer that utilizes image files in general-purpose formats that are written from the original 3DX volume data. Methods We used FLASH MX2004 for Macintosh to develop a simple image viewer. In developing the software for the simple image viewer, we decided that the viewer should provide the following features: (1) be available to both Windows OS and Mac OS, (2) allow interlocking of the 3D images, (3) display image enlargement, and (4) allow distance measurements. The accuracy of the distance measurements was evaluated. Results The procedure was as follows: (1) write 3D images in jpeg format to a folder on i-VIEW; (2) place the folder containing the 3D images into the directory of the simple image viewer software on a PC; (3) start the software and open the window to input the folder name containing the 3D images; and (4) display the 3D images. Our viewer had features such as image enlargement, interlocking 3D images, drawing, and distance measurements. No significant differences were shown between the measurements made by our simple viewer and the actual values of the images in any direction. Conclusions Our image-viewing software for 3DX is beneficial for clinical use.  相似文献   
52.
53.
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.  相似文献   
54.
A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented.  相似文献   
55.
Ryo Hattori  MD    Tateki Kubo  MD    Kenji Yano  MD  PhD    Atsushi Tanemura  MD    Yuji Yamaguchi  MD  PhD    Satoshi Itami  MD  PhD    Ko Hosokawa  MD  PhD 《Dermatologic surgery》2003,29(10):1071-1072
BACKGROUND: Nevus lipomatosus cutaneous superficialis (NLCS) is a relatively rare condition. Although NLCS can affect any region of the entire body, no case of NLCS in the clitoris has ever been reported. OBJECTIVE: To report a case of NLCS of the clitoris that presented manifestations that were similar to female pseudohermaphrodism. METHODS: This is a case report and review of the literature. RESULTS: A congenital, soft, skin-colored lesion of the clitoris in a 1-year-old girl resembled female pseudohermaphrodism. It was resected, and the histologic diagnosis was NLCS. Postoperatively, there was no subsequent change in the lesion during the 3-year follow-up period. CONCLUSION: We reported a case of congenital solitary NLCS of the clitoris. Although NLCS might be a relatively rare condition, we should consider it in the differential diagnosis of female pseudohermaphrodism.  相似文献   
56.
In Takayasu's arteritis (TA), both atypical coarctation (CO) and brachiocephalic involvement are common features that occasionally require operative correction. A combination of these abnormalities could duplicate underlying illness in patients, posing an increased risk of operative morbidity. We present, herein, two TA patients in which hypertensive heart disease secondary to CO was surgically corrected. Both patients had multi-vessel brachiocephalic disease. One patient who showed occlusion of all brachiocephalic arteries underwent aorto-aortic bypass, while another with two-vessel lesion underwent axillo-bifemoral bypass grafting. Subclavian reconstruction was supplemental to each procedure, resulting in relief of neurologic stigmata. Strategies to avoid intraoperative cerebral ischemia played an important role in the surgical repair of such TA-related extensive vascular lesions.  相似文献   
57.
Various tannins and related compounds were compared for their ability to stimulate the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood monocytes. The stimulating activity of most of the monomeric and dimeric hydrolyzable tannins was generally higher than that of the trimeric and tetrameric compounds. Compounds that had dehydrohexahydroxydiphenoyl or chebuloyl groups had considerably less activity than those that had other functional groups (hexahydroxydiphenoyl, valoneoyl, dehydrodigalloyl, isodehydrodigalloyl, lactonized valoneoyl, hellinoyl, euphorbinoyl, dehydroeuphorbinoyl or woodfordinoyl group). The methylated derivative, nonacosa-O-methylcoriariin A, was essentially inactive, suggesting the requirement of a phenolic hydroxyl group. Three condensed tannins ((-)-epicatechin 3-O-gallate (ECG)-dimer, ECG-trimer and ECG-tetramer) significantly stimulated both monocyte iodination and their interleukin-1-like factor production. The results suggest the dependence of stimulation of monocyte iodination by tannins and related polyphenols on molecular weight.  相似文献   
58.
Five hemiplegic patients with intractable epilepsy were studied with transcranial magnetic stimulation (TMS) before and after various surgical treatments. These patients had unilateral widespread cerebral lesions acquired at various times, including congenital, infantile and childhood injury. Motor evoked potentials (MEPs) of the abductor pollicis brevis (APB) muscles were simultaneously recorded on both sides following TMS of the motor cortex in the respective hemisphere using a figure-8 or circular coil. In all patients with congenital disease, the abolition of motor function in the affected hemisphere was estimated by magnetic MEPs, and the hemiplegia did not deteriorate after functional hemispherectomy (HS) was performed in two of them. In two patients with acquired disease, HS was not performed because it was shown by magnetic maps that the motor function in the affected hemisphere remained. Furthermore, it was shown by electric MEPs using subdural electrodes that a patient who had had encephalitis in early childhood had a reorganised motor area in the parietal cortex of the affected hemisphere. The present findings indicate that magnetic MEPs are a very useful non-invasive method of assessing whether the motor area in the affected hemisphere can be resected in hemiplegic patients with intractable epilepsy.  相似文献   
59.
60.
We performed radiofrequency neurotomy of lumbar medial branch as a treatment of facet syndrome. Our six cases had no indication for surgical therapy, such as neuralgia, spinal canal stenosis without neurological deficit except for pain and deformed spines. Facet joint injection with regional anesthetics and steroids could not prevent their recurrent back pain. By facet rhizotomy, they could obtain relief of back pain for several months to a year. We conclude that facet rhizotomy is a more effective method for facet syndrome when a proper indication is present.  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