全文获取类型
收费全文 | 1133篇 |
免费 | 86篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 47篇 |
妇产科学 | 15篇 |
基础医学 | 97篇 |
口腔科学 | 14篇 |
临床医学 | 174篇 |
内科学 | 308篇 |
皮肤病学 | 9篇 |
神经病学 | 100篇 |
特种医学 | 38篇 |
外科学 | 179篇 |
综合类 | 16篇 |
预防医学 | 88篇 |
眼科学 | 7篇 |
药学 | 84篇 |
肿瘤学 | 36篇 |
出版年
2022年 | 7篇 |
2021年 | 27篇 |
2020年 | 13篇 |
2019年 | 19篇 |
2018年 | 12篇 |
2017年 | 21篇 |
2016年 | 23篇 |
2015年 | 18篇 |
2014年 | 26篇 |
2013年 | 43篇 |
2012年 | 68篇 |
2011年 | 49篇 |
2010年 | 22篇 |
2009年 | 36篇 |
2008年 | 52篇 |
2007年 | 53篇 |
2006年 | 52篇 |
2005年 | 44篇 |
2004年 | 67篇 |
2003年 | 55篇 |
2002年 | 42篇 |
2001年 | 38篇 |
2000年 | 44篇 |
1999年 | 35篇 |
1998年 | 16篇 |
1997年 | 14篇 |
1996年 | 14篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1992年 | 13篇 |
1991年 | 22篇 |
1990年 | 18篇 |
1989年 | 21篇 |
1988年 | 13篇 |
1987年 | 19篇 |
1986年 | 15篇 |
1985年 | 18篇 |
1984年 | 12篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 9篇 |
1979年 | 10篇 |
1978年 | 8篇 |
1975年 | 7篇 |
1974年 | 11篇 |
1973年 | 10篇 |
1972年 | 6篇 |
1971年 | 5篇 |
1970年 | 11篇 |
1967年 | 6篇 |
排序方式: 共有1221条查询结果,搜索用时 0 毫秒
71.
72.
The charts of 606 men with anorectal gonorrhea infections treated using the current Public Health Service recommendations were reviewed. There were 3.3% failures in the group treated with penicillin--14.4% in those treated with tetracycline hydrochloride, 14.8% in the ampicillin trihydrate group, and none among those treated with spectinomycin hydrochloride. The intramuscular (IM) injection of penicillin G procaine, 4.8 million units, with 1 g of probenicid given orally is the treatment of choice for anorectal gonorrhea. An IM injection of 2 g of spectinomycin hydrochloride was effective but should be reserved for patients allergic to penicillin and for penicillin treatment failures. 相似文献
73.
The existence of two different units for Thrombin in widespread international use has caused confusion for many years. The holders of the WHO International Standard (IS) for Alpha Thrombin and the US Standard (also known as the "NIH Standard") now report on a collaboration to reunite the International Unit (IU) and the US unit ("NIH unit"). A study was organised involving 25 laboratories in 15 countries to investigate the possibility of preparing a common Standard with a common unit and to investigate aspects of methodology that cause divergence of results using the IS and US Standard. Laboratories were asked to measure the potency of two candidate replacement standards (C, 01/578 and D, 01/580), and potencies were calculated relative to both the existing US Standard (lot J) and the IS (89/588). Data analysis of a total of 128 assays indicated that sample D would make an ideal replacement joint Standard with a potency of 110 IU/ampoule (equivalent to 110 US units per ampoule) based on data from clotting assays. No significant differences in results were observed using fibrinogen of human or bovine origin, or using human plasma. Comparisons of chromogenic and clotting assays indicated that sample D had a similar high proportion of alpha thrombin to the current IS for Alpha Thrombin (89/588). Sample D was adopted as the IS for Thrombin (01/580) and the US Standard (lot K) with a potency of 110 IU/ampoule. 相似文献
74.
McIver SR Lee CS Lee JM Green SH Sands MS Snider BJ Goldberg MP 《Journal of neuroscience research》2005,82(3):397-403
Lentiviral vectors are used widely to direct efficient gene transfer in vivo. We examined cell-specific expression in adult murine white matter after stereotaxic microinjection of four lentiviral constructs. We synthesized vesicular stomatitis virus glycoprotein (VSV-G) pseudotyped lentiviruses with combinations of two promoters, cytomegalovirus (CMV) or myelin basic protein (MBP), and two reporter sequences, cytosolic enhanced green fluorescent protein (eGFP) or a plasma membrane-targeted eGFP (human lymphocyte-specific protein tyrosine kinase [Lck]-eGFP). For all constructs, intracerebral injections to lateral corpus callosum resulted in widespread GFP expression in forebrain white matter glial cells. Intense cellular GFP fluorescence was observed within 3 days after injection and lasted for at least 28 days. The CMV promoter directed GFP expression in multiple glial cell types, whereas the MBP promoter targeted GFP specifically to oligodendrocytes. Expression of the membrane-targeted Lck-eGFP construct distinctly labeled individual myelinating processes of oligodendrocytes. Lentiviral constructs expressing eGFP or Lck-eGFP under the MBP promoter provide excellent visualization of oligodendrocyte morphology in intact white matter, and may prove valuable for delivering additional genes of interest to oligodendrocytes in vivo. 相似文献
75.
Sands JJ 《Blood purification》2005,23(1):45-49
Vascular access monitoring can identify patients at increased risk of future access thrombosis. When coupled with a program of elective stenosis correction, access thrombosis rates decline approximately 50-75%. This results in arteriovenous (AV) fistula thrombosis rates of 0.1-0.2/patient year (vs. 0.2-0.4 at baseline) and AV graft thrombosis rates <0.5/patient year (vs. 0.8-1.2 thromboses/patient year at baseline). Evaluating the long-term impact on access survival remains problematic. There are no large-scale randomized trials and existing studies exhibit marked differences in target populations, clinical protocols and outcome definitions. Differences in payment systems also significantly influence the efficacy of monitoring and intervention programs. Despite these challenges, the current data support the K/DOQI recommendations that all patients undergo a program of regular access monitoring preferably by access flow measurement coupled with prompt imaging and elective stenosis correction for low flow accesses. 相似文献
76.
Griffey M Bible E Vogler C Levy B Gupta P Cooper J Sands MS 《Neurobiology of disease》2004,16(2):360-369
Infantile neuronal ceroid lipofuscinosis (INCL) is the earliest onset form of a class of inherited neurodegenerative disease called Batten disease. INCL is caused by a deficiency in the lysosomal enzyme palmitoyl protein thioesterase-1 (PPT1). Autofluorescent storage material accumulates in virtually all tissues in INCL patients, including the brain, and leads to widespread neuronal loss and cortical atrophy. To determine the efficacy of viral-mediated gene therapy, we injected a recombinant adeno-associated virus 2 vector encoding human PPT1 (rAAV-PPT1) intracranially (I.C.) into a murine model of INCL. INCL mice given four I.C. injections of rAAV-PPT1 as newborns exhibited PPT1 activity near the injection sites and decreased secondary elevations of another lysosomal enzyme. In addition, storage material was decreased in cortical, hippocampal, and cerebellar neurons, and brain weights and cortical thicknesses were increased. These data demonstrate that an adeno-associated virus 2 (AAV2)-mediated gene therapy approach may provide some therapeutic benefit for INCL. 相似文献
77.
The course of certain congenital neurodegenerative diseases like lysosomal storage diseases (LSDs) begins shortly after birth and can progress quickly. Ideally, therapeutic interventions for LSDs, which include bone marrow transplantation (BMT), recombinant enzyme replacement, or systemic viral-mediated gene therapy, should be initiated at birth. However, the blood-brain barrier (BBB) remains an obstacle to effective therapy even when these strategies are initiated at birth. We studied whether VEGF, an endothelial cell mitogen and permeability factor, can open the BBB in newborn mice for therapeutic purposes. Intravenous (IV) administration of VEGF at birth increased BBB permeability within 2 h. The increased permeability persisted for at least 24 h, became undetectable 48 h after injection, and was restricted to newborns. Systemic VEGF treatment before BMT or administration of recombinant lentivirus resulted in increased numbers of both donor cells and virus-transduced cells, respectively, in the recipient brain. Administration of VEGF before BMT in newborn mice with a neurodegenerative LSD, globoid-cell leukodystrophy, resulted in a significant increase in life span compared to affected animals that were injected with saline before BMT. 相似文献
78.
LeGrice I Sands G Hooks D Gerneke D Smaill B 《Clinical and experimental pharmacology & physiology》2004,31(12):902-905
1. Detailed information about three-dimensional structure is key to understanding biological function. 2. Confocal laser microscopy has made it possible to reconstruct three-dimensional organization with exquisite resolution at cellular and subcellular levels. 3. There have been few attempts to acquire large image volumes using the confocal laser scanning microscope. 4. Previously, we have used manual techniques to construct extended volumes (several mm in extent, at 1.5 microm voxel size) of myocardial tissue. 5. We are now developing equipment and efficient automated methods for acquiring extended morphometric databases using confocal laser scanning microscopy. 相似文献
79.
Nyamathi A Sands H Pattatucci-Aragón A Berg J Leake B Hahn JE Morisky D 《Family & community health》2004,27(1):65-74
Perceptions of health status among 331 homeless veterans and homeless nonveterans were examined. Homeless veterans were significantly less apt to perceive their health as fair/poor (8%) compared to non-veteran homeless men (19%). Homeless veterans were also more likely to report having a regular source of care (57% versus 36%). Logistic regression analysis indicated the adjusted odds of fair/poor health were more than two times greater for persons reporting depressive symptomatology than for those without this history; veterans continue to remain less likely to report fair/poor health than nonveterans. High rates of substance abuse were observed for the entire sample. Such differences in perceived health result in important health access issues. 相似文献
80.
Georgopoulos PG Fedele P Shade P Lioy PJ Hodgson M Longmire A Sands M Brown MA 《American journal of industrial medicine》2004,46(5):432-445
BACKGROUND: Hospitals distant from the immediate site of an incident involving a hazardous materials (HAZMATs) release which could include chemical warfare agents, must develop emergency response plans (ERPs) to protect healthcare professionals if they receive potentially contaminated victims. The ERP must address OSHA, EPA, and JCAHO requirements. METHODS: The VHA convened groups to develop a hazard and exposure assessment, identify actions for compliance with existing regulatory standards, and review site and operational planning issues. Exposure modeling results were used to derive relationships between operational parameters (time and distance from sites/sources) and potential exposure for healthcare workers. RESULTS: According to exposure modeling, level C personal protective equipment is adequate to protect hospital staff distant from the chemical release site. Decontamination runoff and contaminated clothing should also be controlled to limit exposure. CONCLUSIONS: Development and coordination of ERPs must include the local emergency planning committee, with clear assignment of tasks, locations, and training in order to prevent exposures to healthcare workers. 相似文献