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   6923篇
  免费   283篇
  国内免费   42篇
耳鼻咽喉   93篇
儿科学   311篇
妇产科学   72篇
基础医学   980篇
口腔科学   65篇
临床医学   463篇
内科学   1613篇
皮肤病学   127篇
神经病学   568篇
特种医学   239篇
外科学   1036篇
综合类   18篇
一般理论   1篇
预防医学   174篇
眼科学   117篇
药学   497篇
中国医学   23篇
肿瘤学   851篇
  2023年   41篇
  2022年   84篇
  2021年   138篇
  2020年   108篇
  2019年   108篇
  2018年   140篇
  2017年   135篇
  2016年   140篇
  2015年   141篇
  2014年   199篇
  2013年   232篇
  2012年   389篇
  2011年   494篇
  2010年   302篇
  2009年   275篇
  2008年   420篇
  2007年   433篇
  2006年   446篇
  2005年   495篇
  2004年   494篇
  2003年   474篇
  2002年   402篇
  2001年   59篇
  2000年   54篇
  1999年   73篇
  1998年   108篇
  1997年   89篇
  1996年   75篇
  1995年   79篇
  1994年   67篇
  1993年   78篇
  1992年   44篇
  1991年   36篇
  1990年   38篇
  1989年   50篇
  1988年   49篇
  1987年   19篇
  1986年   24篇
  1985年   25篇
  1984年   37篇
  1983年   21篇
  1982年   30篇
  1981年   18篇
  1980年   11篇
  1979年   11篇
  1978年   19篇
  1977年   9篇
  1976年   10篇
  1975年   5篇
  1970年   3篇
排序方式: 共有7248条查询结果,搜索用时 10 毫秒
111.
112.
Engineered skin substitutes are widely used in skin wound management. However, no currently available products satisfy all the criteria of usability in emergency situations, easy handling, and minimal scar formation. To overcome these shortcomings, we designed a cell‐free bandage‐type artificial skin, named “VitriBand” (VB), using adhesive film dressing, silicone‐coated polyethylene terephthalate film, and collagen xerogel membrane defined as a dried collagen vitrigel membrane without free water. We analyzed its advantages over in‐line products by comparing VB with hydrocolloid dressing and collagen sponge. For evaluation, mice inflicted with full‐thickness skin defects were treated with VB, hydrocolloid dressing, and collagen sponge. A plastic film group treated only with adhesive film dressing and silicone‐coated polyethylene terephthalate film, and a no treatment group were also compared. VB promoted epithelization while inhibiting the emergence of myofibroblasts and inflammation in the regenerating tissue more effectively than the plastic film, hydrocolloid dressing, and collagen sponge products. We have succeeded in establishing a cell‐free bandage‐type artificial skin that could serve as a promising first‐line medical biomaterial for emergency treatment of skin injuries in various medical situations.  相似文献   
113.
A 63 year-old female presented with dyspnea on exertion. Her chest X-ray showed cardiomegaly, and right ventricular overload and tricuspid regurgitation were detected. Her pulmonary ventilation and blood flow scintigraphy findings were suspicious of pulmonary vascular disease; the diagnosis was pulmonary hypertension and bilateral branch pulmonary artery stenosis. After the inflammation settled, the stenotic bilateral branch pulmonary artery was reconstructed with a prosthetic vessel and the pulmonary pressure normalized immediately. A resected specimen revealed that the stenotic changes were from Takayasu's disease. The patient's postoperative course was uneventful, and pulmonary ventilation and blood scintigraphy returned to an almost normal range. At follow-up 5 years and 6 months after the operation, there was no evidence of pulmonary artery disease (eg, stenosis and/or ischemia) or of any change in the central vessels of the retina, the so-called Takayasu's retinopathy.  相似文献   
114.
To understand whether direct transmission of H. pylori occurs from infected mouse to noninfected mouse, the system using a mouse model we developed previously was tested. Six nude mice were challenged with H. pylori inocula; one group consisted of one challenged nude mouse 1 week after inoculation raised with four nonchallenged nude mice in a single cage. For the single cage, a polycarbonate cage or a mesh-floor cage was used. Then three groups were kept in a polycarbonate cage and the other three groups kept in a mesh-floor cage to avoid H. pylori transmission through stool. After coraising for 1, 2, or 3 weeks, all mice were sacrificed to determine the existence of H. pylori in the stomach, saliva, and stool by culture or PCR and H. pylori-associated gastritis. RAPD fingerprinting patterns using different primers of isolated strains from challenged and nonchallenged mice were compared to understand the origin of transmitted strains. During 3 weeks after coraising of H. pylori challenged and nonchallenged mice, H. pylori was detected in the stomachs in 3 of 12 nonchallenged mice in the polycarbonate cage and in 2 of 12 nonchallenged mice in the cage with a steel mesh floor. H. pylori was detected from saliva or stool in two nonchallenged, infected mice in the polycarbonate cage. Moreover, RAPD fingerprinting using different primers of the total five strains isolated from five nonchallenged, infected mice in both cages showed the same pattern and concordance with that of the challenged strain and the strains isolated from challenged mice. It is demonstrated that intimate interaction is the cause of H. pylori transmission via saliva and stool.  相似文献   
115.
A 68-year-old man was admitted to our hospital presenting cutaneous pruritic lesions consisting of tense blisters with serous content on his arms and legs. Histological findings of skin biopsy confirmed a diagnosis of bullous pemphigoid in March 2005. After 10 weeks of prednisone therapy for bullous pemphigoid, he presented with increasing breathlessness and high fever. He was admitted to our hospital because of severe hypoxemia on May 29, 2005, and mechanical ventilation was started from the first hospital day. Chest computed tomography showed marked ground-glass opacities in both lungs. The levels of beta-D glucan and KL-6 in his sera were elevated. We suspected Pneumocystis pneumonia and Cytomegalovirus pneumonia. Under mechanical ventilation, he received steroid pulse therapy, and sulfamethoxazole-trimethoprim and ganciclovir. A polymerase chain reaction assay of bronchoalveolar lavage fluid showed Pneumocysitis DNA and Cytomegalovirus DNA. On the 12th hospital day, he was weaned from mechanical ventilation. Follow-up chest computed tomography showed marked resolution of diffuse ground-glass opacity in both lungs. We need to consider the development of Pneumocystis pneumonia and Cytomegalovirus pneumonia during steroid therapy for bullous pemphigoid.  相似文献   
116.
117.
Recent studies have highlighted the mechanism of vascular and axonal guidance to ensure proper morphogenesis and organogenesis. We aimed to perform global mapping of developing neurovascular networks during craniofacial development of embryonic mice. To this end, we developed histology‐based three‐dimensional (3D) reconstructions using paraffin‐embedded serial sections obtained from mouse embryos. All serial sections were dual‐immunolabeled with Pecam1 and Pgp9.5/Gap43 cocktail antibodies. All immunolabeled serial sections were digitized with virtual microscopy to acquire high spatial resolution images. The 3D reconstructs warranted superior positional accuracy to trace the long‐range connectivity of blood vessels and individual cranial nerve axons. It was feasible to depict simultaneously the details of angiogenic sprouting and axon terminal arborization and to assess quantitatively the locoregional proximity between blood vessels and cranial nerve axons. Notably, 3D views of the craniofacial region revealed the following: Branchial arch arteries and blood capillary plexi were formed without accompanying nerves at embryonic day (E) 9.5. Cranial nerve axons began to grow into the branchial arches, developing a labyrinth of small blood vessels at E10.5. Vascular remodeling occurred, and axon terminals of the maxillary, mandibular, chorda tympani, and hypoglossal nerve axons had arborized around the lateral lingual swellings at E11.5. The diverged patterning of trigeminal nerves and the arterial branches from the carotid artery became congruent at E11.5. The overall results support the advantage of dual‐immunolabeling and 3D reconstruction technology to document the architecture and wiring of the developing neurovascular networks in mouse embryos. Anat Rec, 298:1824–1835, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
118.
Vascular access intervention therapy (VAIVT) is necessary to maintain vascular access in patients undergoing hemodialysis. VAIVT‐associated vasodilatation is painful. However, few reports have focused on effective pain relief at the time of VAIVT. The present study was performed to determine whether lidocaine‐propitocain cream, a eutectic mixture of local anesthetics (EMLA), effectively reduces VAIVT‐associated pain in patients undergoing hemodialysis. This placebo‐controlled, double‐blind, crossover study was conducted in a single center. Among 210 patients who underwent a total of 437 VAIVT procedures from August 2017 to June 2018, 30 patients were randomly allocated to either the EMLA–placebo arm or placebo–EMLA arm at the time of VAIVT. EMLA application significantly reduced the visual analog scale score compared with placebo (47.0 ± 21.1 vs. 68.6 ± 20.7 mm, respectively; P < 0.05). EMLA is a safe and effective treatment for relief of VAIVT‐associated pain in patients undergoing hemodialysis.  相似文献   
119.
120.
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