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排序方式: 共有1524条查询结果,搜索用时 15 毫秒
71.
J B Smith F C Luft M B Wade N S Fineberg M H Weinberger 《Clinica chimica acta; international journal of clinical chemistry》1987,170(1):89-96
In hemodialyzed patients, the serum albumin concentration determined by the bromcresol purple (BCP) method was lower than that determined by an immunological method. The degree of underestimation appeared to be well correlated to the serum concentration of 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), a major endogenous ligand substance present in uremic serum. CMPF inhibited in vitro the binding of BCP to serum protein and human serum albumin. Our results suggest that CMPF is a major interferent in the underestimation of the serum albumin concentration by the BCP method in uremia. 相似文献
72.
Birkenfeld Andreas L.; Gollasch Maik; Gobel Ursula; Luft Friedrich C. 《Nephrology, dialysis, transplantation》2004,19(6):1643-1645
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Potassium is the most common intracellular cation and approximately 98% is intracellular. The plasma level reflects only 2% of the potassium content. The absorption rate is approximately 70 mmol/24 h and from this 95% is excreted from the kidneys and 5% from the intestines. A 1% shift in potassium from intracellular to extracellular would mean a 100% change in the plasma level meaning that the rapid ingestion of a steak could be fatal. The body is protected from this by a fine regulation of the potassium distribution via the cell membranes. Recent research has also shown that there is also signaling between the gastrointestinal tract and the kidneys, which can immediately result in excretion of potassium without incurring alterations to the plasma or aldosterone levels. In patients with hypokalemia it is necessary to thoroughly investigate the acid-base balance in order to come to the correct diagnosis. The best therapy for hypokalemia is to remove the cause. 相似文献
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Tobias Wächter Sebastian Röhrich Anita Frank Katiuska Molina-Luna Ana Pekanovic Benjamin Hertler Maximilan Schubring-Giese Andreas R. Luft 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2010,200(3-4):319-323
Functional imaging studies in humans and electrophysiological data in animals suggest that corticostriatal circuits undergo plastic modifications during motor skill learning. In motor cortex and hippocampus circuit plasticity can be prevented by protein synthesis inhibition (PSI) which can interfere with certain forms learning. Here, the hypothesis was tested that inducing PSI in the dorsal striatum by bilateral intrastriatal injection of anisomycin (ANI) in rats interferes with learning a precision forelimb reaching task. Injecting ANI shortly after training on days 1 and 2 during 4 days of daily practice (n = 14) led to a significant impairment of motor skill learning as compared with vehicle-injected controls (n = 15, P = 0.033). ANI did not affect the animals’ motivation as measured by intertrial latencies. Also, ANI did not affect reaching performance once learning was completed and performance reached a plateau. These findings demonstrate that PSI in the dorsal striatum after training impairs the acquisition of a novel motor skill. The results support the notion that plasticity in basal ganglia circuits, mediated by protein synthesis, contributes to motor skill learning. 相似文献
78.
Four Clones of Borrelia burgdorferi Sensu Stricto Cause Invasive Infection in Humans 总被引:4,自引:0,他引:4
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Gerald Seinost Daniel E. Dykhuizen Raymond J. Dattwyler William T. Golde John J. Dunn Ing-Nang Wang Gary P. Wormser Martin E. Schriefer Benjamin J. Luft 《Infection and immunity》1999,67(7):3518-3524
Lyme disease begins at the site of a tick bite, producing a primary infection with spread of the organism to secondary sites occurring early in the course of infection. A major outer surface protein expressed by the spirochete early in infection is outer surface protein C (OspC). In Borrelia burgdorferi sensu stricto, OspC is highly variable. Based on sequence divergence, alleles of ospC can be divided into 21 major groups. To assess whether strain differences defined by ospC group are linked to invasiveness and pathogenicity, we compared the frequency distributions of major ospC groups from ticks, from the primary erythema migrans skin lesion, and from secondary sites, principally from blood and spinal fluid. The frequency distribution of ospC groups from ticks is significantly different from that from primary sites, which in turn is significantly different from that from secondary sites. The major groups A, B, I, and K had higher frequencies in the primary sites than in ticks and were the only groups found in secondary sites. We define three categories of major ospC groups: one that is common in ticks but very rarely if ever causes human disease, a second that causes only local infection at the tick bite site, and a third that causes systemic disease. The finding that all systemic B. burgdorferi sensu stricto infections are associated with four ospC groups has importance in the diagnosis, treatment, and prevention of Lyme disease. 相似文献
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Jefford M Schnurr M Toy T Masterman KA Shin A Beecroft T Tai TY Shortman K Shackleton M Davis ID Parente P Luft T Chen W Cebon J Maraskovsky E 《Blood》2003,102(5):1753-1763
Dendritic cells (DCs) are a family of leukocytes that initiate T- and B-cell immunity against pathogens. Migration of antigen-loaded DCs from sites of infection into draining lymphoid tissues is fundamental to the priming of T-cell immune responses. In humans, the major peripheral blood DC (PBDC) types, CD1c+ DCs and interleukin 3 receptor-positive (IL-3R+) plasmacytoid DCs, are significantly expanded in vivo with the use of Flt3 ligand (FL). DC-like cells can also be generated from monocyte precursors (MoDCs). A detailed comparison of the functional potential of these types of DCs (in an autologous setting) has yet to be reported. Here, we compared the functional capacity of FL-expanded CD1c+ PBDCs with autologous MoDCs in response to 3 different classes of stimuli: (1) proinflammatory mediators, (2) soluble CD40 ligand trimer (CD40L), and (3) intact bacteria (Escherichia coli). Significant differences in functional capacities were found with respect to changes in phenotype, migratory capacity, cytokine secretion, and T-cell stimulation. MoDCs required specific stimuli for the expression of functions. They responded vigorously to CD40L or E coli, expressing cytokines known to regulate interferon-gamma (IFN-gamma) in T cells (IL-12p70, IL-18, and IL-23), but required prostaglandin E2 (PGE2) during stimulation to migrate to chemokines. In contrast, PBDCs matured in response to minimal stimulation, rapidly acquired migratory function in the absence of PGE2-containing stimuli, and were low cytokine producers. Interestingly, both types of DCs were equivalent with respect to stimulation of allogeneic T-cell proliferation and presentation of peptides to cytotoxic T lymphocyte (CTL) lines. These distinct differences are of particular importance when considering the choice of DC types for clinical applications. 相似文献