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71.
Eight patients with Fanconi's anemia were given cyclophosphamide alone (seven patients) or combined with procarbazine and antithymocyte globulin (one patient) followed by marrow grafts from HLA-identical siblings. All patients had engraftment. Seven developed acute and three chronic graft-versus-host disease (GVHD). Three patients died with GVHD and infectious complications (days 19, 56, and 82) and one with an intracerebral hemorrhage (day 540). Four patients are surviving 647- 3435 days after grafting, two are well, and two have chronic GVHD that is improving. These results show that Fanconi's anemia can be treated successfully by allogeneic marrow transplantation.  相似文献   
72.
A series of four mannose(Man)-, three N-acetylglucosamine (GlcNAc)n-, ten N-acetylgalactosamine/galactose(GalNAc/Gal)-, one 5-acetylneuraminic acid (alpha-2,3-Gal/GalNAc)- and one 5-acetylneuroaminic acid(alpha-2,6-Gal/Gal-NAc)-specific plant agglutinins were evaluated for their antiviral activity in vitro. the mannose-specific lectins from the orchid species Cymbidium hybrid (CA), Epipactis helleborine (EHA) and Listera ovata (LOA) were highly inhibitory to human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) in MT-4, and showed a marked anti-human cytomegalovirus (CMV), respiratory syncytial virus (RSV) and influenza A virus activity in HEL, HeLa and MDCK cells, respectively. The 50% effective concentration (EC50) of CA and EHA for HIV ranged from 0.04 to 0.08 micrograms/ml, that is about 3 orders of magnitude below their toxicity threshold (50% inhibitory concentration for MT-4 cell growth: 54 to 60 micrograms/ml). Also, the (GlcNAc)n-specific lectin from Urtica dioica (UDA) was inhibitory to HIV-1-, HIV-2-, CMV-, RSV- and influenza A virus-induced cytopathicity at an EC50 ranging from 0.3 to 9 micrograms/ml. The GalNAc/Gal-, alpha-2,3-Gal/GalNAc- or alpha-2,6-Gal/GalNAc-specific lectins were not inhibitory to HIV or CMV at non-toxic concentrations. CA, EHA and UDA proved to be potent inhibitors of syncytium formation between persistently HIV-1- and HIV-2-infected HUT-78 cells and CD4+ Molt/4 (clone 8) cells (EC50: 0.2-2 micrograms/ml). Unlike dextran sulfate, the plant lectins CA, EHA and UDA did not interfere with HIV-1 adsorption to MT-4 cells and RSV- and influenza A virus adsorption to HeLa and MDCK cells, respectively. They presumably interact at the level of virion fusion with the target cell.  相似文献   
73.
The acyclic nucleoside phosphonate analogue (S)-1-[3-hydroxy-2-phosphonylmethoxypropyl]cytosine (HPMPC) is a potent and selective inhibitor of human cytomegalovirus (HCMV) replication and DNA synthesis. Unlike 9-(1,3-dihydroxy-2-propoxymethyl)guanine (DHPG), HPMPC inhibits HCMV replication in cell cultures which have been treated with the compound before infection. Upon short-pulse treatment of HCMV-infected cells with HPMPC, a long-lasting antiviral response is obtained. The antiviral activity of HPMPC, unlike the antiviral activity of other cytosine derivatives (i.e. Ara-C, FIAC), is not readily reversed by 2'-deoxycytidine or cytidine. Neutral and alkaline sucrose gradient analysis of HCMV DNA isolated from HPMPC-treated HCMV-infected cell cultures revealed that HPMPC does not cause (detectable) single- or double-strand breakage of HCMV DNA.  相似文献   
74.
Formycin A, formycin B, and the N1-, N2-, 2′-O- and 3′-O-methyl derivatives of formycin A, were all examined for activity against vaccinia, herpes simplex and vesicular stomatitis viruses in primary rabbit kidney cells. The susceptibilities of calf intestinal adenosine deaminase to all the formycin A derivatives, relative to those of some adenosine analogues, were measured in order to take into account the possible effects of intracellular deamination on the antiviral and cytotoxic effects of the formycin derivatives. Formycin B was found to be inactive in all assay systems. Formycin A exhibited significant antiviral activity only against vesicular stomatitis virus, but it also proved relatively toxic to the host cells, appreciably inhibiting cellular DNA and RNA sunthesis as measured by incorporation of labelled thymidine and uridine, respectively. Of the methylated analogues, N1-methylformycin A (which was highly resistant to enzymatic deamination) and the 2′-O-metyhlderivatives of formycin A were totally inactive in all three viral assay systems. Only N2-methylformycin exhibited relatively high activity againts vaccinia virus, was not toxic to the cells, and did not affect cellular DNA and RNA synthesis.  相似文献   
75.
BACKGROUND AND OBJECTIVE: A recombinant lipoprotein vaccine against Lyme disease, containing 30 microg of Borrelia burgdorferi outer surface protein A (OspA) with aluminum adjuvant, has been shown in a large US field trial of subjects >/=15 years of age to offer 76% efficacy against clinical Lyme disease after 3 injections given at 0, 1, and 12 months. Lyme disease is also an important problem in children; thus, OspA vaccine trials in children are needed. The purpose of this study was to investigate the safety and immunogenicity of 2 different doses of lipoprotein OspA with aluminum adjuvant vaccine in healthy children 5 to 15 years of age in a double-blind, randomized study. STUDY DESIGN: In a double-blind study, 250 children from the Czech Republic were randomly assigned to receive 15 microg or 30 microg of OspA vaccine at 0, 1, and 2 months. Serum samples, obtained before vaccination and 1 month after the second and third doses, were analyzed for antiOspA antibody. Solicited and unsolicited symptoms were collected from diary cards. RESULTS: Local pain at the injection site was reported by approximately 76% of the 250 children. Headaches (after 5% to 18% of the injections) and malaise (after 2% to 16% of the injections) were the most frequently reported general symptoms. Local and generalized symptoms were not different between the 15 microg and 30 microg groups, and all symptoms resolved within 4 days. Both doses were highly immunogenic, with the 30 microg dose eliciting higher antibody levels. Seroconversion occurred in 99% of the 250 children. CONCLUSIONS: The OspA vaccine against Lyme disease was well tolerated and highly immunogenic in children.  相似文献   
76.
77.
N-(adamantyl-1)methyl, N-(adamantyl-2), and N-(omega-aminodecyl) amides of vancomycin, eremomycin, and dechloroeremomycin aglycons and their des-(N-Me-D-Leu) derivatives were synthesized and their antibacterial and anti-HIV activities were investigated. Carboxamides with an intact peptide core demonstrated activity against glycopeptide-susceptible and -resistant bacteria (1-32 microM). N-(adamantyl-1)methylcarboxamide of eremomycin aglycons had good antiretroviral activity (1.6 microM against HIV-1). Compounds with destroyed peptide core [des-(N-Me-D-Leu)-aglycon amides] were inactive against both glycopeptide-sensitive and -resistant bacteria. (Adamantyl-1)methylamide of des-(N-Me-D-Leu)-eremomycin aglycon had good antiretroviral activity (EC50 of 5.5 microM for HIV-1 and 3.5 microM for HIV-2). (Adamantyl-1)methylamides of eremomycin aglycon and its des-(N-Me-d-Leu)-derivative are the most promising and selective antiretroviral agents. Their ability to induce bacterial resistance to glycopeptide antibiotics during prolonged administration may be expected to be very low or absent. This might make the use of these derivatives feasible in the prolonged therapy or prophylaxis of HIV infections.  相似文献   
78.
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80.
5-Fluorouracil, 5-fluorouridine (FUrd), 5-fluoro-2'-deoxyuridine (FdUrd), 5-fluorocytidine (FCyd), 5-fluoro-2'-deoxycytidine (FdCyd), 5-trifluoro-2'-deoxythymidine (F3dThd), and the 5'-monophosphates and 3',5'-cyclic monophosphates thereof were found to inhibit thymidine kinase-deficient (TK-) mutant strains of herpes simplex virus (HSV) at a much lower concentration than the wild-type (TK+) HSV strains. Other 5-substituted 2'-deoxyuridines that have previously been recognized as potent thymidylate synthase inhibitors behaved in a similar fashion. The activity of FdUrd, FdCyd, F3dThd, and their 3',5'-cyclic monophosphates against TK-HSV was readily reversed by 2'-deoxythymidine (dThd) but not by 2'-deoxyuridine (dUrd). These compounds also inhibited the incorporation of [6-3H]dUrd into DNA at a concentration which was up to 5 orders of magnitude lower than the concentration at which the incorporation of [methyl-3H] dThd was inhibited. Thus, while not being a target for the well established anti-HSV compounds in TK+HSV-infected cells, thymidylate synthase appears to be an important target in TK-HSV-infected cells. In addition to dTMP synthase, TK-HSV-infected cells appear to reveal other therapeutically exploitable targets such as OMP decarboxylase (towards pyrazofurin), CTP synthase (towards carbodine and its cyclopentenyl analogue), dihydrofolate reductase (towards methotrexate), and S-adenosylhomocysteine hydrolase (towards neplanocins).  相似文献   
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