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   3179篇
  免费   374篇
  国内免费   232篇
耳鼻咽喉   10篇
儿科学   20篇
妇产科学   15篇
基础医学   265篇
口腔科学   16篇
临床医学   69篇
内科学   183篇
皮肤病学   43篇
神经病学   54篇
特种医学   42篇
外科学   92篇
综合类   524篇
预防医学   48篇
眼科学   15篇
药学   1335篇
  1篇
中国医学   1031篇
肿瘤学   22篇
  2024年   24篇
  2023年   49篇
  2022年   86篇
  2021年   125篇
  2020年   115篇
  2019年   92篇
  2018年   84篇
  2017年   129篇
  2016年   151篇
  2015年   172篇
  2014年   304篇
  2013年   245篇
  2012年   239篇
  2011年   265篇
  2010年   174篇
  2009年   160篇
  2008年   153篇
  2007年   188篇
  2006年   147篇
  2005年   132篇
  2004年   105篇
  2003年   97篇
  2002年   65篇
  2001年   55篇
  2000年   35篇
  1999年   31篇
  1998年   27篇
  1997年   28篇
  1996年   23篇
  1995年   18篇
  1994年   17篇
  1993年   19篇
  1992年   12篇
  1991年   15篇
  1990年   15篇
  1989年   10篇
  1988年   20篇
  1987年   12篇
  1986年   19篇
  1985年   18篇
  1984年   12篇
  1983年   14篇
  1982年   8篇
  1981年   16篇
  1980年   15篇
  1979年   6篇
  1978年   6篇
  1977年   8篇
  1976年   8篇
  1970年   5篇
排序方式: 共有3785条查询结果,搜索用时 15 毫秒
1.
目的探讨儿童流感应用帕拉米韦注射液治疗的临床疗效以及用药安全性。方法随机选定在2016年1月-2019年1月期间佛山市高明区人民医院儿科住院治疗并确诊流感A或B型患儿200例,通过随机数字法将其分为治疗组和对照组。治疗组100例用帕拉米韦注射液治疗,对照组100例用国产磷酸奥司他韦颗粒治疗,评价两组患儿治疗前后症状评分、治疗效果、治疗指标以及不良反应发生情况。结果两组患儿治疗前流感样症状评分无统计学意义(P>0.05),两组患儿治疗后较治疗前流感样症状评分均下降,差异有统计学意义(P<0.05);治疗组治疗后流感样症状评分略小于对照组,但是无统计学意义(P>0.05);治疗组治疗总有效率高于对照组,治疗组患儿发热症状缓解、全部症状缓解以及住院时间均小于对照组,存在统计学意义(P<0.05)。治疗组与对照组不良反应发生率较低,且无统计学意义(P>0.05)。结论帕拉米韦注射液可用于儿童流感治疗,不仅能够保证临床疗效,而且可加快症状缓解,同时存在较高用药安全性。  相似文献   
2.
In this study breast tissue that contained ultrastructural dense core granules has been examined from 24 patients. The possible neuroendocrine characteristics of the granules were studied using the uranaffin reaction and an ultrastructural argyrophil stain. The tissue included 15 breast carcinomas and nine benign samples. Two types of breast dense core granules can be distinguished on the basis of intracellular distribution patterns and histochemical reactivity. Type I dense core granules are the most common and they were found subluminally distributed in non-pathological tissues and benign lesions as well as carcinomas. They were uranaffin-negative and are unlikely to be of endocrine nature. Type II dense core granules were found only in four carcinomas, where they occurred abundantly throughout the cytoplasm. These granules were uranaffin-positive and argyrophilic and thus exhibited characteristics consistent with neuroendocrine structure.  相似文献   
3.
 Actinomycetous infections typically involve either the head and neck or the extremities following a traumatic implantation. Classic clinical associations are draining sinus tracts. This case report describes the pathologic and MR findings of a relatively acute mycetomatous process involving the soft tissues. Pathologic findings in this case included an occasional granule composed of gram positive, thin branching elements. These and other findings were consistent with actinomycetes bacterium infection. The discussion centers around the use of MR, both with and without gadolinium, in evaluating this type of granulomatous infection. Infiltration of the adjacent subcutaneous tissues was easier to appreciate on both the T1-weighted images without gadolinium and the T1-weighted images with gadolinium when compared to the T2-weighted images. Signal characteristics as described in this case report may suggest a granulomatous process.  相似文献   
4.
5.
Most cases of anal abscess are caused by anal fistula and invasion of the surrounding tissues by a mixed colonic flora. Treatment consists of excision of the abscess and, in case of fistula, fistulectomy. Primary anorectal and perianal forms of actinomycosis are very rare and caused by actinomyces, as ubiquitous anaerobics bacterium. We report a case of perianal actinomycosis. The patient had a short history of painless perineal induration without fever and leukocytosis with normal results at routine blood examination. After excision, sulfur granules drained from the cavity and pathological investigations indicated perianal actinomycosis. Appropriate surgery and antibiotic treatment healed the perianal infection. After exclusion of possible diagnoses such as Crohn’s disease, tuberculosis and malignant growths, the rare case of perianal actinomycosis should be considered in the differential diagnosis of painless perianal masses.  相似文献   
6.
宣肺清热颗粒剂稳定性研究   总被引:1,自引:0,他引:1  
目的:研究宣肺清热颗粒剂中橙皮甙热稳定性变化,为该颗粒剂有效期的确定、制剂生产、贮存条什提供实验参考依据。方法:采用加速实验法对橙皮甙热稳定性进行研究,用甲醇超声提取样品,HPLC进行含量测定。根据Arrhenius公式处理数据。结果:Arrhenius公式得室温下的速度常数K298=3.38×10-5/h,得出常温下该颗粒剂以橙皮甙为指标的有效期为3.6年。结论:宣肺清热颗粒剂稳定性好,初步符合中药稳定性要求。  相似文献   
7.
A melanotic paraganglioma occurred in a 57-year-old woman, located in the left paravertebral space of the upper mediastinum. It was totally resected. During a 5 year follow up period neither tumour reccurrence nor metastasis were observed. Histological examination of the tumour revealed a paraganglioma with monomorphous chief cell like elements which were arranged in a zellballen pattern. Immunohistochemical results also were in accordance with the diagnosis since neuron-specific enolase, chromogranin and synaptophysin were found in tumour cells whereas keratin was not. Additionally, neurosecretory granules were found in tumour cells during electron microscopy. A peculiar feature of the tumour was its strong pigmentation due to melanin located within the tumour cells and tumour associated melanophages. The simultaneous expression of functional properties of two different neural crest derived cells in one tumour stresses the close relationship between all neural crest elements and is in accordance with the observation of other melanotic, non-melanomatous tumours.Dedicated to Prof. Dr. Dr. mult. h.c. W. Doerr on the occasion of his 80th birthday  相似文献   
8.
9.
A case of primary malignant laryngeal carcinoid with dual endocrine and mucous differentiation i s reported. Histologically the tumor showed a characteristic organoid pattern and exhibited Alcian-blue, periodic acidschiff, and Grimelius silver positivity. By the immunoperoxidase technique cal citoni n, ACTH, and or-hCG subunit were demonstrated in the tumor cells. ELectron microscopy revealed two different types of endocrinelike cells: mucous cells and occasional cells containing both endocrinelike granules and mucin droplets. Diagnostic morphologic criteria of this rare tumor entity are discussed and reference t o biologic behavior and possible h istogenesis is made.  相似文献   
10.
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