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991.
Maryam Nabati M.D. Babak Bagheri M.D. Valiolla Habibi M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(5):E132-E135
Pulmonary agenesis is characterized by undeveloped pulmonary vessels, bronchi as well as lung parenchyma and is a rare congenital anomaly with unknown etiology. It is usually diagnosed during childhood. Nearly, one third of these patients have concomitant congenital heart diseases. While more than 50% of these patients die before the age of 5 years, some other patients may be asymptomatic throughout their life. On the other hand, common atrium, another rare congenital anomaly, is characterized by complete absence of the atrial septum and is usually accompanied by atrioventricular valve malformations. An 18‐year‐old male presented with concomitant pulmonary agenesis and common atrium and had not undergone surgery due to high risk for mortality. 相似文献
992.
993.
Maryam M. Asgari John G. Haggerty Jennifer M. McNiff Leonard M. Milstone Pauline M. Schwartz 《Journal of cutaneous pathology》1999,26(6):287-294
Thymidine phosphorylase/platelet-derived endothelial cell growth factor (TPase/PD-ECGF) is a catabolic enzyme that has been shown to be chemotactic for endothelial cells in vitro and angiogenic in vivo. TPase/PD-ECGF expression is increased in a variety of tumors. In the skin, TPase is active in normal keratinocytes in vitro and in vivo. Our objective was to study the expression and localization of TPase/PD-ECGF by immunohistochemical analysis in normal skin and cutaneous tumors and to correlate this information with enzymatic activity of TPase. TPase/PD-ECGF expression was observed in keratinocytes with intense staining of the infundibulum of hair follicles but no staining of hair bulbs. Expression localized primarily to the nucleus of keratinocytes in the basal layer but was more intense and cytoplasrmic in suprabasal keratinocytes. Increased expression of TPase/PD-ECGF in differentiated cells was confirmed by in vitro studies of TPase activity. In cutaneous tumors, there was positive staining for TPase/ PD-ECGF in squamous cell carcinomas (10/10), eccrine poromas (3/4), eccrine syringomas (4/4), trichoepitheliomas (1/3), and tumors of the follicular infundibulum (2/3) and melanomas (5/8). There was no staining of any intradermal nevi (0/2), basal cell carcinomas (0/10) or Merkel cell carcinoma (0/1). We conclude TPase/PD-ECGF is found throughout the epidermis and its expression increases with differentiation of keratinocytes. In cutaneous tumors, expression of TPase/PD-ECGF may be linked to the cell of origin of the tumor as well as the tumor's degree of differentiation. 相似文献
994.
In vertebrates, brain development takes place at the expanded anterior end of the neural tube. After closure of the anterior neuropore, the brain wall forms a physiologically sealed cavity that encloses embryonic cerebrospinal fluid (E‐CSF), a complex and protein‐rich fluid. E‐CSF has several crucial roles in brain anlagen development. In this respect, during the initiation of neurogenesis, increases in the volume of brain cavities account for 70% of the total growth of the brain primordium, and are accompanied by a parallel increase in E‐CSF volume. Recently, we reported the presence of several blood vessels located in the brain stem lateral to the ventral midline, at the mesencephalon and prosencephalon level, which have a transient blood‐CSF barrier function in chick embryos by transporting proteins in a selective manner via transcellular routes. These blood vessels control E‐CSF protein composition and homeostasis during this early stage of CNS development, just after closure of the neuropores. Here we report that in chick and rat embryos these same blood vessels, which lie close to the neuroectoderm, express several molecules related to water and ion transport, namely AQP1, AQP4 and Kir4.1. Our results confirm that a blood‐CSF barrier controls E‐CSF composition and homeostasis from early stages of brain development in chick embryos, including water and ion influx, thus regulating E‐CSF osmolarity. On the basis of our findings, we also propose that a similar blood‐CSF barrier is present in mammals at equivalent developmental stages of the brain. © 2009 Wiley‐Liss, Inc. 相似文献
995.
996.
Mohammad Ali Kashani Farid Fereidoun Azizi Mehdi Hedayati Maryam S Daneshpour Ahmad Reza Shamshiri Fereydoun Siassi 《Lipids in health and disease》2010,9(1):96
Background
Low level of high density lipoprotein cholesterol (HDL-C) has high prevalence in the Tehran Lipid and Glucose Study (TLGS) cohort. About 50% of the inter-individual variation in serum HDL-C levels is genetically determined. Polymorphisms in cholesteryl ester transfer protein (CETP) and hepatic lipase (LIPC) genes have been found to be associated with the metabolism and serum concentration of the HDL-C. 相似文献997.
998.
Maryam Nabati M.D. Rahman Ghaffari M.D. Ali Ghaemian M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(10):E315-E318
A sinus of Valsalva aneurysm is a dilatation of the aortic wall caused by the lack of continuity between the middle layer of the aortic wall and the aortic valve. It has an incidence of <0.1%. The most common cause of a sinus of Valsalva aneurysms is congenital, although they may also be acquired. The most common complication is rupture into the right atrium or ventricle, with rupture into the left chambers occurring very rarely. We present a 40‐year‐old man admitted to the hospital with an acute onset of respiratory distress and pleuritic chest pain. Transthoracic echocardiography followed by transesophageal echocardiography showed rupture of a noncoronary aneurysm of Valsalva sinus into the left atrium. The jet from the fistula caused retrograde flow into the pulmonary veins. 相似文献
999.
Picture Archiving and Communications System (PACS) was originally developed for radiology services over 20 years ago to capture medical images electronically. Medical diagnosis methods are based on images such as clinical radiographs, ultrasounds, CT scans, MRIs, or other imaging modalities. Information obtained from these images is correlated with patient information. So with regards to the important role of PACS in hospitals, we aimed to evaluate the PACS and survey the information security needed in the Radiological Information system. First, we surveyed the different aspects of PACS that should be in any health organizations based on Department of Health standards and prepared checklists for assessing the PACS in different hospitals. Second, we surveyed the security controls that should be implemented in PACS. Checklists reliability is affirmed by professors of Tehran Science University. Then, the final data are inputted in SPSS software and analyzed. The results indicate that PACS in hospitals can transfer patient demographic information but they do not show route of information. These systems are not open source. They don’t use XML-based standard and HL7 standard for exchanging the data. They do not use DS digital signature. They use passwords and the user can correct or change the medical information. PACS can detect alternation rendered. The survey of results demonstrates that PACS in all hospitals has the same features. These systems have the patient demographic data but they do not have suitable flexibility to interface network or taking reports. For the privacy of PACS in all hospitals, there were passwords for users and the system could show the changes that have been made; but there was no water making or digital signature for the users. 相似文献
1000.
Tulen Pekny Maryam Faiz Ulrika Wilhelmsson Maurice A. Curtis Radoslav Matej Omar Skalli Milos Pekny 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2014,122(1):76-80
Alexander disease (AxD) is a neurodegenerative disorder with prominent white matter degeneration and the presence of Rosenthal fibers containing aggregates of glial fibrillary acidic protein (GFAP), and small stress proteins HSP27 and αB‐crystallin, and widespread reactive gliosis. AxD is caused by mutations in GFAP, the main astrocyte intermediate filament protein. We previously showed that intermediate filament protein synemin is upregulated in reactive astrocytes after neurotrauma. Here, we examined immunohistochemically the presence of synemin in reactive astrocytes and Rosenthal fibers in two patients with AxD. There was an abundance of GFAP‐positive Rosenthal fibers and widespread reactive gliosis in the white matter and subpial regions. Many of the GFAP‐positive reactive astrocytes were positive for synemin, and synemin was also present in Rosenthal fibers. We show that synemin is expressed in reactive astrocytes in AxD, and is also present in Rosenthal fibers. The potential role of synemin in AxD pathogenesis remains to be investigated. 相似文献