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   2423篇
  免费   113篇
  国内免费   24篇
耳鼻咽喉   15篇
儿科学   30篇
妇产科学   37篇
基础医学   283篇
口腔科学   23篇
临床医学   100篇
内科学   730篇
皮肤病学   22篇
神经病学   157篇
特种医学   129篇
外科学   315篇
综合类   4篇
预防医学   75篇
眼科学   54篇
药学   85篇
中国医学   4篇
肿瘤学   497篇
  2023年   19篇
  2022年   33篇
  2021年   78篇
  2020年   33篇
  2019年   53篇
  2018年   53篇
  2017年   41篇
  2016年   66篇
  2015年   66篇
  2014年   79篇
  2013年   87篇
  2012年   153篇
  2011年   166篇
  2010年   94篇
  2009年   100篇
  2008年   147篇
  2007年   163篇
  2006年   140篇
  2005年   139篇
  2004年   139篇
  2003年   105篇
  2002年   125篇
  2001年   33篇
  2000年   38篇
  1999年   31篇
  1998年   30篇
  1997年   33篇
  1996年   26篇
  1995年   23篇
  1994年   32篇
  1993年   29篇
  1992年   23篇
  1991年   27篇
  1990年   13篇
  1989年   14篇
  1988年   15篇
  1987年   14篇
  1986年   12篇
  1985年   7篇
  1984年   4篇
  1982年   7篇
  1981年   6篇
  1980年   6篇
  1979年   11篇
  1978年   6篇
  1977年   5篇
  1974年   4篇
  1973年   3篇
  1965年   3篇
  1927年   5篇
排序方式: 共有2560条查询结果,搜索用时 15 毫秒
31.
BACKGROUND: Although thrombolysis is a standard therapy in cases of pulmonary embolism (PE), fatal outcome is often observed. We designed and investigated the efficacy of a novel percutaneous catheter therapy, rotational bidirectional thrombectomy (ROBOT), for PE. METHODS AND RESULTS: Eighteen patients with acute massive PE (Miller score > or = 20) were included in this study. We separated them into two groups [group A (n = 10), thrombolysis; group B (n = 8): thrombolysis and ROBOT or ROBOT alone]. There was no difference in the hemodynamic indices between the groups at diagnosis. ROBOT was designed to fragment emboli by rotating a regular pigtail catheter. Three deaths occurred in group A because of hemodynamic impairment, but there was no death in group B. One day after treatment, systolic pulmonary artery pressure had decreased from 53 +/- 8 to 30 +/- 8 mm Hg (P < 0.05) in group B and from 54 +/- 5 to 42 +/- 19 mm Hg (NS) in group A. The hospitalization period in group B was shorter than that in group A (17 +/- 6 vs. 27 +/- 10 days, P < 0.05). CONCLUSION: ROBOT therapy results in a significant, rapid improvement in the hemodynamic situation and in a better outcome than conventional therapy in patients with acute massive pulmonary embolism.  相似文献   
32.
We classified ipsilateral breast tumor recurrences (IBTRs) based on strict pathological rules. Ninety‐six women who were surgically treated for IBTR were included. IBTRs were classified according to their origins and were distinguished based on strict pathological rules: relationship between the IBTR and the primary lumpectomy scar, surgical margin status of the primary cancer, and the presence of in situ lesions of IBTR. The prognosis of these subgroups were compared to that of new primary tumors (NP) in the narrow sense (NPn) that occurred far from the scar. Distant‐disease free survival of IBTR that occurred close to the scar with in situ lesions and a negative surgical margin of the primary cancer (NP occurred close to the scar, NPcs) was similar to that of NPn. In contrast, IBTR that occurred close to the scar without in situ lesions (true recurrence (TR) that arose from residual invasive carcinoma foci, TRinv) had significantly poorer prognosis than NPn. IBTR that occurred close to the scar with in situ lesions and a positive surgical margin of the primary cancer (TR arising from a residual in situ lesion, TRis) had more late recurrences than NPcs. Precise pathological examinations indicated four distinct IBTR subtypes with different characteristics.  相似文献   
33.
Journal of Gastroenterology - REFLECT was an open-label, phase 3 study comparing the efficacy and safety of lenvatinib versus sorafenib in patients with unresectable hepatocellular carcinoma...  相似文献   
34.
The epidermal basement membrane is a specialized structure localized between the epidermis and the dermis. Recent studies have elucidated the biological roles of the basement membrane and its pathophysiological involvement in bullous diseases. To understand the functions of the basement membrane, it is essential to have clear and precise information regarding the ultrastructural molecular organization of the epidermal basement membrane. Immunoelectron microscopy is a powerful technique and the only method available for the clarification of the ultrastructural localization or orientation of molecules. This review summarizes the latest information regarding the molecular organization of the epidermal basement membrane as determined by immunoelectron microscopy as well as the blistering diseases that occur in the epidermal basement membrane zone.  相似文献   
35.
Paroxysmal abnormal eye movement in early infancy is one of the initial symptoms of glucose transporter 1 deficiency syndrome (GLUT1DS). We describe four early infants with transient hypoglycorrhachia presenting with abnormal eye movements. Their symptoms disappeared after the introduction of a ketogenic diet (KD), and their development was normal. Since no variants in SLC2A1 were detected, the CSF-to-blood glucose ratios (C/B) were re-examined, and within normal range. None of the four patients displayed recurrent symptoms after withdrawal from the KD. Because long-term KD has potential adverse effects and could affect the quality of life of patients and their families, re-examination of CSF glucose during late infancy should be considered in the case of absence of the SLC2A1 pathogenic variant.  相似文献   
36.
Journal of Artificial Organs - Infection is a major complication in patients with a left ventricular assist device (LVAD). Once a driveline exit-site infection (DLI) reaches the LVAD component,...  相似文献   
37.
Journal of Artificial Organs - A 45-year-old woman with repaired complex congenital heart disease, who underwent placement of Jarvik 2000, a ventricular assist device (VAD) for 4&nbsp;years,...  相似文献   
38.
39.
Frozen shoulder is a relatively common disorder that leads to severe pain and stiffness in the shoulder joint. Although this disorder is self‐limiting in nature, the symptoms often persist for years, resulting in severe disability. Recent studies using human specimens and animal models have shown distinct changes in the gene expression patterns in frozen shoulder tissue, indicating that novel therapeutic intervention could be achieved by controlling the genes that are potentially involved in the development of frozen shoulder. To achieve this goal, it is imperative to develop a reliable animal joint contracture model in which gene expression can be manipulated by gene targeting and transgenic technologies. Here, we describe a novel shoulder contracture mouse model. We found that this model mimics the clinical presentation of human frozen shoulder and recapitulates the changes in the gene expression pattern and the histology of frozen shoulder and joint contracture in humans and other larger animal models. The model is highly reproducible, without any major complications. Therefore, the present model may serve as a useful tool for investigating frozen shoulder etiology and for identifying its potential target genes. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1732–1738, 2015.  相似文献   
40.
Purkinje fibers play essential roles in impulse propagation to the ventricles, and their functional impairment can become arrhythmogenic. However, little is known about precise spatiotemporal pattern(s) of interconnection between Purkinje-fiber network and the underlying ventricular myocardium within the heart. To address this issue, we simultaneously visualized intracellular Ca(2+) dynamics at Purkinje fibers and subjacent ventricular myocytes in Langendorff-perfused rat hearts using multi-pinhole type, rapid-scanning confocal microscopy. Under recording of electrocardiogram at room temperature spatiotemporal changes in fluo3-fluorescence intensity were visualized on the subendocardial region of the right-ventricular septum. Staining of the heart with either fluo3, acetylthiocholine iodide (ATCHI), or di-4-ANEPPS revealed characteristic structures of Purkinje fibers. During sinus rhythm (about 60 bpm) or atrial pacing (up to 3 Hz) each Purkinje-fiber exhibited spatiotemporally synchronous Ca(2+) transients nearly simultaneously to ventricular excitation. Ca(2+) transients in individual fibers were still synchronized within the Purkinje-fiber network not only under high-K(+) (8 mM) perfusion-induced Purkinje-to-ventricular (P-V) conduction delay, but also under unidirectional, orthodromic P-V block produced by 10-mM K(+) perfusion. While spontaneous, asynchronous intracellular Ca(2+) waves were identified in injured fibers of Purkinje network locally, surrounding fibers still exhibited Ca(2+) transients synchronously to ventricular excitation. In summary, these results are the first demonstration of intracellular Ca(2+) dynamics in the Purkinje-fiber network in situ. The synchronous Ca(2+) transients, preserved even under P-V conduction disturbances or under emergence of Ca(2+) waves, imply a syncytial role of Purkinje fibers as a specialized conduction system, whereas unidirectional block at P-V junctions indicates a substrate for reentrant arrhythmias.  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