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11.
Sensitive immunoassays are essential for establishing the efficacy of recombinant vaccines to hepatitis B virus (HBV). These experimental vaccines include the PreS2 and S domains of the HBV envelope protein. To facilitate measurement of antibody against HBV PreS2, we employed the immuno-ligand assay with silicon sensor-based detection. Labeling of immune reagents with the haptens biotin and fluorescein allows adaptation to the immunofiltration light addressable potentiometric sensor (LAPS) system. A biotinylated monoclonal anti-PreS2 antibody and anti-PreS2 in clinical serum samples competitively bind in liquid phase to a fluorescein labeled PreS2 + S antigen. Streptavidin mediates the immobilization on biotinylated nitrocellulose membranes. Fluorescein mediates binding of an anti-fluorescein urease conjugate to the immune complex. Urease serves as the signal-generating component which subsequently is measured in the LAPS reader. In comparison to a competitive RIA, the immuno-ligand assay demonstrated a four-fold improved sensitivity using a smaller sample volume. The higher sensitivity resulted in earlier detection of seroconversion during a clinical vaccine study. 相似文献
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Field Tiffany; Hernandez-Reif Maria; Seligmen Susan; Krasnegor Josh; Sunshine William; Rivas-Chacon Rafael; Schanberg Saul; Kuhn Cynthia 《Journal of pediatric psychology》1997,22(5):607-617
Studied children with mild to moderate juvenile rheumatoid arthritiswho were massaged by their parents 15 minutes a day for 30 days(and a control group engaged in relaxation therapy). The children'sanxiety and stress hormone (cortisol) levels were immediatelydecreased by the massage, and over the 30-day period their paindecreased on self-reports, parent reports, and their physician'sassessment of pain (both the incidence and severity) and pain-limitingactivities 相似文献
15.
Bojian Zheng Ming-Liang He King-Ling Wong Ching Tung Lum Leo L M Poon Ying Peng Yi Guan Marie C M Lin Hsiang-Fu Kung 《Journal of interferon & cytokine research》2004,24(7):388-390
We sought to investigate the anti-severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV) activities of type I (alpha and beta) and type II (gamma) interferons (IFN) in vitro. Type I IFNs protected cells from cytopathic effects (CPE) induced by SCoV, and inhibited viral genomic RNA replication in FRhk-4 cells (measured by quantitative RT-PCR) in a dose-dependent manner. Intracellular viral RNA copies were reduced 50% by IFN-alpha at a concentration of 25 U/ml and by IFN-beta at a concentration of 14 U/ml. IFN-gamma had fewer effects on inhibition of viral infection and replication. The type I IFN receptor signaling pathway in host cells is mainly involved in the inhibition of SCoV infection and replication. Type I IFNs could be used as potential agents for anti-SARS treatment. 相似文献
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Frantiek Moravec Isaure de Buron Tiffany G. Baker David González-Solís 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(4):382-391
Three gonad-infecting species of Philometra Costa, 1845 were, for the first time, recorded from perciform fishes from estuarine and marine waters in South Carolina and
Georgia, USA: Philometra charlestonensis sp. nov. from the scamp Mycteroperca phenax (Jordan et Swain) (Serranidae), P. saltatrix Ramachandran, 1973 from the bluefish Pomatomus saltatrix (Linnaeus) (Pomatomidae), and Philometra sp. from the Atlantic croaker Micropogonias undulatus (Linnaeus) (Sciaenidae). The new species is characterized mainly by males (body length 2.65–3.14 mm) with equally long, needle-like
spicules (length 132–141 μm) and the gubernaculum (81–93 μm) bearing dorsal transverse lamella-like structures on its distal
portion, the body length of gravid females (168–247 mm), the presence of a well-developed anterior bulbous inflation on the
female oesophagus, and by the length of the first-stage larvae (544–597 μm). A key to gonad-infecting species of Philometra parasitizing marine and brackish-water fishes is provided. 相似文献
18.
Flow Perfusion Culture of Marrow Stromal Cells Seeded on Porous Biphasic Calcium Phosphate Ceramics 总被引:2,自引:0,他引:2
Holtorf HL Sheffield TL Ambrose CG Jansen JA Mikos AG 《Annals of biomedical engineering》2005,33(9):1238-1248
Calcium phosphate ceramics have been widely used for filling bone defects to aid in the regeneration of new bone tissue. Addition of osteogenic cells to porous ceramic scaffolds may accelerate the bone repair process. This study demonstrates the feasibility of culturing marrow stromal cells (MSCs) on porous biphasic calcium phosphate ceramic scaffolds in a flow perfusion bioreactor. The flow of medium through the scaffold porosity benefits cell differentiation by enhancing nutrient transport to the scaffold interior and by providing mechanical stimulation to cells in the form of fluid shear. Primary rat MSCs were seeded onto porous ceramic (60% hydroxyapatite, 40% β-tricalcium phosphate) scaffolds, cultured for up to 16 days in static or flow perfusion conditions, and assessed for osteoblastic differentiation. Cells were distributed throughout the entire scaffold by 16 days of flow perfusion culture whereas they were located only along the scaffold perimeter in static culture. At all culture times, flow perfused constructs demonstrated greater osteoblastic differentiation than statically cultured constructs as evidenced by alkaline phosphatase activity, osteopontin secretion into the culture medium, and histological evaluation. These results demonstrate the feasibility and benefit of culturing cell/ceramic constructs in a flow perfusion bioreactor for bone tissue engineering applications. 相似文献
19.
Human haplotype block sizes are negatively correlated with recombination rates 总被引:3,自引:0,他引:3 下载免费PDF全文
The International Haplotype Map ("HapMap") Project is motivated, in part, by the belief that the organization of the human genome, the mechanics of recombination, and the population-level behavior of alleles at adjacent loci should allow researchers to parse the genome into small segments, or "blocks," that show strong linkage disequilibrium (LD) between alleles at loci within those segments. The discovery and evidence for these blocks is to be based solely on the observed LD strength and patterns between alleles at adjacent loci throughout the genome. Although there are many factors that contribute to LD strength, we assessed the correlation between block structure, in terms of length and percentage of the genome assembled into blocks within a region, and recombination rate obtained from two independent sources. We found evidence of a striking negative correlation between the average recombination rate and average block length, suggesting that recombination rate is a strong contributor to haplotype block structure within the genome. We discuss the potential implications of this negative correlation in the context of the organization, properties, and potential ubiquity of a block-like structure in the human genome. 相似文献
20.
S.-H. Kung S.-F. Wang C.-W. Huang C.-C. Hsu H.-F. Liu J.-Y. Yang 《Clinical microbiology and infection》2007,13(8):782-787
Enterovirus 71 (EV71) infections can lead to devastating clinical outcomes in children, with an increasing number of severe cases worldwide. The genetic and antigenic variability of EV71 strains isolated in Taiwan in 1998-2005 was evaluated using partial nucleotide sequence analysis of the VP1 gene and the neutralisation assay. Phylogenetic analyses revealed that most EV71 isolates from the 1998 epidemic belonged to sub-genogroup C2, with a minority belonging to sub-genogroup B4. Between 1999 and 2003, isolates belonging to sub-genogroup B4 predominated, followed by a change to sub-genogroup C4 in 2004 and 2005. Antibodies raised in rabbits or collected from infected patients were able to neutralise EV71 virus stocks at high dilutions, regardless of the sub-genogroup of the virus being challenged. The presence of phylogenetically distinct yet antigenically similar populations of EV71 in Taiwan is of concern in the context of herd immunity and vaccine development. 相似文献