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   1978628篇
  免费   145046篇
  国内免费   3793篇
耳鼻咽喉   28721篇
儿科学   66611篇
妇产科学   55614篇
基础医学   281044篇
口腔科学   53946篇
临床医学   171022篇
内科学   394667篇
皮肤病学   42504篇
神经病学   156282篇
特种医学   78740篇
外国民族医学   939篇
外科学   305578篇
综合类   43038篇
现状与发展   1篇
一般理论   598篇
预防医学   148118篇
眼科学   44657篇
药学   145316篇
  2篇
中国医学   3878篇
肿瘤学   106191篇
  2018年   20043篇
  2017年   15441篇
  2016年   16814篇
  2015年   19093篇
  2014年   26845篇
  2013年   41285篇
  2012年   56250篇
  2011年   59621篇
  2010年   35883篇
  2009年   34154篇
  2008年   57080篇
  2007年   61028篇
  2006年   61288篇
  2005年   59967篇
  2004年   58100篇
  2003年   56325篇
  2002年   55273篇
  2001年   93329篇
  2000年   96559篇
  1999年   82155篇
  1998年   22673篇
  1997年   20646篇
  1996年   20893篇
  1995年   19663篇
  1994年   18666篇
  1993年   17426篇
  1992年   64814篇
  1991年   63222篇
  1990年   61660篇
  1989年   58847篇
  1988年   54364篇
  1987年   53556篇
  1986年   50382篇
  1985年   48342篇
  1984年   36210篇
  1983年   30663篇
  1982年   18163篇
  1981年   16255篇
  1979年   32939篇
  1978年   22957篇
  1977年   19421篇
  1976年   18303篇
  1975年   19904篇
  1974年   23575篇
  1973年   22658篇
  1972年   21106篇
  1971年   19245篇
  1970年   18393篇
  1969年   16848篇
  1968年   15770篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
The first COVID-19 vaccination was given in December 2020 and there is an effort to vaccinate the international population on a massive scale. Common side effects from the vaccine include headache and tiredness. Regional lymphadenopathy has been described in relation to other vaccines. We describe two cases of supraclavicular reactive lymphadenopathy presenting in patients who had the COVID vaccination in the ipsilateral arm. Awareness of this diagnosis is important for patients presenting to the neck lump clinic.  相似文献   
82.
Fibroepithelial polyps (FEPs) are common, benign intraoral lesions that tend to develop slowly at predictable sites, often in response to local irritation or trauma. Historical precedent often results in referral to oral and maxillofacial surgery (OMFS) departments for biopsy, often irrespective of symptoms, and histological assessment. OMFS and pathology services are struggling to cope with an increasing workload that will potentially lead to widespread delays to diagnosis and treatment. Over the past 20 years, clinical pathways and guidance have been developed to ensure that healthcare interventions, such as the removal of third molars, tonsils, skin tags, and benign moles, are evidence-based, have a net patient benefit, and ensure the best use of finite NHS resources. However, no such guidance exists for intraoral lesions and we regard this as an oversight. We analysed the removal of 682 FEPs over a seven-year period and report sensitivities of 92.4% for a “confirmed clinical suspicion of an FEP” and 99.7% for a “confirmed clinical suspicion of a benign diagnosis”. The incidence of non-benign disease was 0.3%. Primary care dentists should be able to diagnose and monitor FEPs and refer only if symptoms are serious or in high-risk patients or sites. Adopting this practice across the UK could free up to 1825 four-hour OMFS clinics, 405 hours of consultant histopathologists’ time, and recurring savings to the NHS estimated to be in the region of £620 000/annum. We believe that the removal of FEPs should be reclassified as an “intervention not normally funded”, and the time and resources put to better use treating patients with lesions of questionable pathology.  相似文献   
83.
Zygomatic implant treatment is widely applied for severe maxillary atrophy to help rehabilitate the maxillary dentition. This retrospective study was performed to evaluate the actual radiographic bone–implant contact (rBIC) lengths of zygomatic implants. The records of 28 patients who underwent zygomatic implant surgery and subsequent follow-up examinations between August 2013 and September 2018 in the Department of Oral and Maxillofacial Surgery, Taipei Tzu Chi Hospital were reviewed. The surgeries were performed by a single surgeon using the same treatment protocol. All patients had a computed tomography scan at 1 year after the surgery. Using three-dimensional imaging software, an investigator measured the rBIC lengths of 66 implants and documented their clinical status. The implant survival rate was 100%. The mean rBIC length was significantly longer in male patients than in female patients (20.80 ± 5.88 mm versus 17.79 ± 6.34 mm; P = 0.028). The mean rBIC length of double zygomatic implants was significantly longer when compared to that of single implants (21.11 ± 6.23 mm versus 17.75 ± 5.85 mm; P = 0.027). This article is novel in reporting the exact rBIC lengths of zygomatic implants in a clinical setting. The results showed that zygomatic implants are a viable treatment modality for full-mouth rehabilitation.  相似文献   
84.
85.
86.
87.
Rheological behaviour of pharmaceutical semisolid preparations significantly affects manufacturing process, administration, stability, homogeneity of incorporated drug, accuracy of dosing, adhesion in the place of application, drug release, and resulting therapeutic effect of the product. We performed test of consistency by penetrometry, rotational, oscillation and creep tests, and squeeze and tack tests of model samples to introduce methods suitable for characterization and comparison of semisolids in practice. Penetrometry is a simple method allowing sorting the semisolids to low and high stress-resistant materials but deficient for rheological characterization of semisolids. Value of yield stress, generally considered to be appropriate feature of semisolids, is significantly influenced by the method of testing and the way of evaluation. The hysteresis loops of model semisolids revealed incomplete thixotropy, therefore, three-step thixotropy test was employed. Semisolids showed nonlinear response in the creep phase of tests and partial recovery of structure by storing energy in the recovery phase. Squeeze and tack tests seem to be convenient ways for comparison of semisolids. Our study can contribute to a better understanding of different flow behaviour of semisolids given by different physicochemical properties of excipients and can bring useful approaches to evaluation and comparison of semisolids in practice.  相似文献   
88.
This paper revisits a 2003 publication in Nursing Philosophy: The need for accurate perception and informed judgement in determining the appropriate use of the nursing resource: hearing the patient's voice. The author suggests that the basic ideas and focus of this 16‐year‐old paper are still topical and relevant in considerations of nursing care. However, it is also suggested that greater attention to the importance of the nurse–patient relationship in considerations of resource allocation, and potential rationing of nursing care, would have strengthened the original paper.  相似文献   
89.
90.
Phang  P. Terry 《Abdominal imaging》2019,44(11):3740-3742
Abdominal Radiology -  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