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排序方式: 共有940条查询结果,搜索用时 31 毫秒
21.
AbstractBackground: Prion diseases or transmissible spongiform encephalopathies (TSEs) are neurodegenerative syndromes caused by proteinaceous infectious particles (or “prions”), are fatally progressive, and affect humans and animals. Human prion disease may be familial, sporadic, or due to iatrogenic causes. The signs and symptoms include dementia, ataxia, myoclonus, dysautonomia, pyramidal and extrapyramidal tract signs, and akinesia. The incubation period of iatrogenic TSE ranges from 15 months to 30 years, and clinical presentations may be atypical.Design: Case report.Findings: This article presents the case study of a 39-year-old man who fell at work and subsequently complained of subjective lower extremity weakness, followed by onset of ataxia, bowel and bladder incontinence, and progressive decline in ambulation over 6 months. In the absence of a unifying diagnosis, the patient was presumed to have had a spinal cord injury (SCI). Because neuro-axis imaging studies fail ed to explain his symptoms, the patient's complaints were thought to have a large psychologic component. The patient then developed neurologic abnormalities proximal to the presumed SCI. Somatosensory evoked potentials were suggestive of a thoracic or lumbar cord myelopathy and cerebrospinal fluid analysis was suggestive of prion disease. Family members eventually revealed that the patient had had injections of growth hormones derived from cadaveric human pituitary glands as a child. Postmortem brain examination later revealed definitive Creutzfeldt-Jakob disease. 相似文献
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Human platelet membrane glycoproteins IIb and IIIa (GPIIb and IIIa) were incorporated into phospholipid vesicles by the reverse-phase technique to assess the ability of GPIIb and IIIa to function as a Ca2+ channel. Movement of Ca2+ across the lipid bilayer was quantitated by injection of proteoliposomes with encapsulated Fura-2 into Ca2+ buffers and measurement of Fura-2 fluorescence as an indicator of Ca2+ influx. Reciprocally, to assess the function of proteins in an inside-out orientation, Ca2+-loaded vesicles were injected into Ca2+-free buffer and Ca2+ efflux monitored by a calcium electrode. Incorporation of the IIb-IIIa complex produced significant facilitation of Ca2+ movement across the lipid bilayer. No net transmembrane Ca2+ movement was seen with dissociated IIb and IIIa. Movement of Ca2+ was proportional to the transmembrane Ca2+ gradient. Ca2+ movement into the vesicles was inversely proportional to extravesicular NaCl from 25 to 150 mmol/L, analogous to several studies in the intact platelet. Adenosine triphosphate had no effect on Ca2+ movement into or out of the vesicles. Specific inhibition of a Ca2+ shift into the vesicles was seen with M148, a monoclonal antibody to IIb/IIIa, while no inhibition was observed with a panel of other anti-IIb/IIIa monoclonal antibodies. This suggests that a specific site on the complex or orientation of the complex is essential for calcium channel function. These data demonstrate that the GPIIb/IIIa complex can serve as a passive Ca2+ channel across a phospholipid bilayer and has the potential to play a role in Ca2+ flux across the platelet plasma membrane. 相似文献
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Rachel Lampert Brian Olshansky Hein Heidbuchel Christine Lawless Elizabeth Saarel Michael Ackerman Hugh Calkins Mark Estes Mark Link Barry Maron Frank Marcus Melvin Scheinman Bruce Wilkoff Douglas Zipes Charles Berul Alan Cheng Ian Law Michelle Loomis Cheryl Barth Cynthia Brandt David Cannom 《Heart rhythm》2012,9(9):1577-1578
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Kenneth C. Hohmeier Benjamin Loomis Justin Gatwood 《Research in social & administrative pharmacy》2018,14(4):360-366
Background
Point-of-care testing (POCT) is a specialty of laboratory medicine that occurs at the bedside or near the patient when receiving health services. Despite its clinical utility, POCT implementation in the community pharmacy setting is slow due to uncertainty about the market for this novel service and remuneration for services rendered.Objective
To identify 1) demographics and 2) willingness-to-pay preferences of the market niche of consumers who prefer to receive POCT services in the community pharmacy.Methods
A sample of 188 participants matched to the U.S. population were surveyed in February of 2016 utilizing a self-explicated conjoint analysis survey model.Results
Age groups differed between the community pharmacy consumer niche and the entire sample. The largest age group of the pharmacy niche consumer group were between 20 and 34 years old. Of those who preferred the community pharmacy setting to receive POCT services, 75% indicated they would be willing to pay $50 or more compared to 79% of the entire sample who preferred to pay $50 or less.Conclusions
There exists a latent and niche group of consumers interested in community pharmacy provided POCT services. This market niche is younger, and in general willing-to-pay more than the general population for these tests. 相似文献27.
M Roussomoustakaki J Satsangi K Welsh E Louis G Fanning S Targan C Landers DP Jewell 《Gastroenterology》1997,112(6):1845-1853
BACKGROUND & AIMS: Recent studies have suggested that HLA DRB1*0103 and allele 2 of the interleukin 1 receptor antagonist (IL-1RA) gene predict severe and extensive ulcerative colitis, respectively. The aim of this study was to test these hypotheses in patients undergoing surgery for their colitis. METHODS: HLA DRB1 and DQB1 genotyping was performed in 99 patients and 472 controls. Genotyping for polymorphisms of genes encoding tumor necrosis factor alpha and IL-1RA was performed in 107 patients and 89 controls. Measurement of antineutrophil cytoplasmic antibody (ANCA) was performed in 72 patients and 58 healthy subjects by fixed neutrophil enzyme-linked immunosorbent assay and indirect immunofluorescence. RESULTS: The DRB1*0103 allele was increased in patients (14.1% vs. 3.2% in controls; P < 1 x 10[-5]). This association was greatest in patients with extensive disease (15.8%; P < 0.0001) or extraintestinal manifestations (22.8%; P < 0.0001): mouth ulcers (25.8%; P < 0.0001), arthritis (27.2%; P < 0.0001), and uveitis (35.7%; P < 0.0001). The DRB1*04 alleles were reduced in patients (P = 0.005). Differences were noted between extensive and distal disease in the frequency of allele 2 of IL-1RA (10.9% in distal vs. 28.6% in extensive; P = 0.01) and allele 2 homozygosity. ANCA was detected in 76.4% of patients. Carriage of IL-1RA allele 2 and tumor necrosis factor 2 allele was increased in ANCA-positive patients. CONCLUSIONS: Genetic markers may predict disease behavior in ulcerative colitis. (Gastroenterology 1997 Jun;112(6):1845-53) 相似文献
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Arterial chemoembolization for hepatocellular carcinoma 总被引:10,自引:1,他引:10
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Blanton RL Fuller D Iranfar N Grimson MJ Loomis WF 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(5):2391-2396
Cellulose is a major component of the extracellular matrices formed during development of the social amoeba, Dictyostelium discoideum. We isolated insertional mutants that failed to accumulate cellulose and had no cellulose synthase activity at any stage of development. Development proceeded normally in the null mutants up to the beginning of stalk formation, at which point the culminating structures collapsed onto themselves, then proceeded to attempt culmination again. No spores or stalk cells were ever made in the mutants, with all cells eventually lysing. The predicted product of the disrupted gene (dcsA) showed significant similarity to the catalytic subunit of cellulose synthases found in bacteria. Enzyme activity and normal development were recovered in strains transformed with a construct expressing the intact dcsA gene. Growing amoebae carrying the construct accumulated the protein product of dcsA, but did not make cellulose until they had developed for at least 10 hr. These studies show directly that the product of dcsA is necessary, but not sufficient, for synthesis of cellulose. 相似文献