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排序方式: 共有407条查询结果,搜索用时 31 毫秒
41.
42.
White Pages misses important population segments 总被引:1,自引:0,他引:1
Sharon Lawn 《Australian and New Zealand journal of public health》2001,25(2):472-472
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44.
Hermann I Bhowmick S Lawn BR 《Journal of biomedical materials research. Part B, Applied biomaterials》2007,82(1):115-121
A study is made of veneer failure by cracking in all-ceramic crown-like layer structures. Model trilayers consisting of a 1 mm thick external glass layer (veneer) joined to a 0.5 mm thick inner stiff and hard ceramic support layer (core) by epoxy bonding or by fusion are fabricated for testing. The resulting bilayers are then glued to a thick compliant polycarbonate slab to simulate a dentin base. The specimens are subjected to cyclic contact (occlusal) loading with spherical indenters in an aqueous environment. Video cameras are used to record the fracture evolution in the transparent glass layer in situ during testing. The dominant failure mode is cone cracking in the glass veneer by traditional outer (Hertzian) cone cracks at higher contact loads and by inner (hydraulically pumped) cone cracks at lower loads. Failure is deemed to occur when one of these cracks reaches the veneer/core interface. The advantages and disadvantages of the alumina and zirconia core materials are discussed in terms of mechanical properties-strength and toughness, as well as stiffness. Consideration is also given to the roles of interface strength and residual thermal expansion mismatch stresses in relation to the different joining methods. 相似文献
45.
People,processes, and systems: An observational study of the role of technology in rural youth mental health services
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Simone Orlowski Sharon Lawn Ben Matthews Anthony Venning Gabrielle Jones Megan Winsall Gaston Antezana Niranjan Bidargaddi Peter Musiat 《International journal of mental health nursing》2017,26(3):259-272
The merits of technology‐based mental health service reform have been widely debated among academics, practitioners, and policy makers. The design of new technologies must first be predicated on a detailed appreciation of how the mental health system works before it can be improved or changed through the introduction of new products and services. Further work is required to better understand the nature of face‐to‐face mental health work and to translate this knowledge to computer scientists and system designers responsible for creating technology‐based solutions. Intensive observation of day‐to‐day work within two rural youth mental health services in South Australia, Australia, was undertaken to understand how technology could be designed and implemented to enhance young people's engagement with services and improve their experience of help seeking. Data were analysed through a lens of complexity theory. Results highlight the variety of professional roles and services that can comprise the mental health system. The level of interconnectedness evident in the system contrasted with high levels of service self‐organization and disjointed information flow. A mental health professional's work was guided by two main constructs: risk and engagement. Most clients presented with a profile of disability, disadvantage, and isolation, so complex client presentations and decision‐making were core practices. Clients (and frequently, their families) engaged with services in a crisis‐dependent manner, characterized by multiple disengagements and re‐engagements over time. While significant opportunities exist to integrate technology into existing youth mental health services, technologies for this space must be usable for a broad range of medical, psychological and cognitive disability, social disadvantage, and accommodate repeat cycles of engagement/disengagement over time. 相似文献
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Pisell TL Hoffman IF Jere CS Ballard SB Molyneux ME Butera ST Lawn SD 《AIDS (London, England)》2002,16(11):1503-1509
OBJECTIVES: To determine the impact of Plasmodium falciparum malaria coinfection and its treatment on cellular reservoirs of viral replication in HIV-1-infected persons and to relate this to changes in systemic immune activation. METHODS: Plasma samples were obtained from HIV-1-infected individuals (n = 10) at diagnosis of acute malaria, 4 weeks after parasite clearance and from HIV-infected aparasitemic controls (n = 10). Immunomagnetic HIV-1 capture analysis was used to determine the cellular origin of cell-free virus particles present in all 30 plasma samples and indices of immune activation were measured using enzyme-linked immunosorbent assays. RESULTS: Compared with controls, the detectable proportion of HIV-1 particles derived from CD14 macrophages and CD26 lymphocytes was increased in persons with acute malaria coinfection and correlated with markedly increased plasma concentrations of both proinflammatory cytokines and soluble markers of macrophage and lymphocyte activation. Parasite clearance following treatment with antimalarial drugs resulted in decreased detection of HIV-1 particles derived from the CD14 macrophage cell subset and correlated with a marked diminution in systemic immune activation. CONCLUSIONS: Acute P. falciparum malaria coinfection impacts virus-host dynamics in HIV-1-infected persons at the cellular level, notably showing a reversible induction of HIV-1 replication in CD14 macrophages that is associated with changes in immune activation. 相似文献
48.
Leukocyte and fibroblast interferon genes are located on human chromosome 9. 总被引:15,自引:12,他引:15
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D Owerbach W J Rutter T B Shows P Gray D V Goeddel R M Lawn 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(5):3123-3127
At least eight leukocyte interferon genes (IFL) and the single fibroblast interferon gene (IFF) have been located on chromosome 9 in humans. In somatic cell hybrids of human and mouse cells containing a normal complement of mouse parental cell chromosomes but reduced numbers of human chromosomes, the human leukocyte and fibroblast interferon DNA sequences were present only when human chromosome 9 was also present. 相似文献
49.
Partial amino acid sequence of apolipoprotein(a) shows that it is homologous to plasminogen. 总被引:20,自引:3,他引:20
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D L Eaton G M Fless W J Kohr J W McLean Q T Xu C G Miller R M Lawn A M Scanu 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(10):3224-3228
Apolipoprotein(a) [apo(a)] is a glycoprotein with Mr approximately equal to 280,000 that is disulfide linked to apolipoprotein B in lipoprotein(a) particles. Elevated plasma levels of lipoprotein(a) are correlated with atherosclerosis. Partial amino acid sequence of apo(a) shows that it has striking homology to plasminogen. Plasminogen is a plasma serine protease zymogen that consists of five homologous and tandemly repeated domains called kringles and a trypsin-like protease domain. The amino-terminal sequence obtained for apo(a) is homologous to the beginning of kringle 4 but not the amino terminus of plasminogen. Apo(a) was subjected to limited proteolysis by trypsin or V8 protease, and fragments generated were isolated and sequenced. Sequences obtained from several of these fragments are highly (77-100%) homologous to plasminogen residues 391-421, which reside within kringle 4. Analysis of these internal apo(a) sequences revealed that apo(a) may contain at least two kringle 4-like domains. A sequence obtained from another tryptic fragment also shows homology to the end of kringle 4 and the beginning of kringle 5. Sequence data obtained from two tryptic fragments show homology with the protease domain of plasminogen. One of these sequences is homologous to the sequences surrounding the activation site of plasminogen. Plasminogen is activated by the cleavage of a specific arginine residue by urokinase and tissue plasminogen activator; however, the corresponding site in apo(a) is a serine that would not be cleaved by tissue plasminogen activator or urokinase. Using a plasmin-specific assay, no proteolytic activity could be demonstrated for lipoprotein(a) particles. These results suggest that apo(a) contains kringle-like domains and an inactive protease domain. 相似文献
50.
Grace Liu Joel Segrè A Metin Gülmezoglu Matthews Mathai Jeffrey M Smith Jorge Hermida Aline Simen-Kapeu Pierre Barker Mercy Jere Edward Moses Sarah G Moxon Kim E Dickson Joy E Lawn Fernando Althabe Working Group for the UN Commission of Life Saving Commodities Antenatal Corticosteroids 《BMC pregnancy and childbirth》2015,15(Z2):S3