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991.
In a mixed continuous culture of Pseudomonas putida VM15A and Pseudomonas sp. strain VM15C with polyvinyl alcohol (PVA) as the sole source of carbon, growth of the PVA-degrading bacterium VM15C and, hence, PVA degradation were limited by the growth factor, pyrroloquinoline quinone, produced by VM15A. Feeding of a carbon source for VM15A, ethanol, with PVA enhanced pyrroloquinoline quinone production and caused increases in the VM15C population and PVA degradation in a mixed continuous culture. There was an optimum range for PVA degradation of the ethanol concentration, although pyrroloquinoline quinone concentrations in continuous mixed cultures increased with increasing ethanol concentration.  相似文献   
992.
Summary The possibility that a plant lectin as a carrier protein would specifically activate T cells, resulting in the augmentation of antitumor immunity was investigated. ATF1011, a nonmitogenic lectin for T cells purified from Aloe arborescens Mill, bound equally to normal and tumor cells. ATF1011 binding on the MM102 tumor cell surfaces augmented anti-trinitrophenyl (TNP) antibody production of murine splenocytes when the mice were primarily immunized with TNP-conjugated MM102 tumor cells. The alloreactive cytotoxic T cell response was also augmented by allostimulator cells binding ATF1011 on the cell surfaces. These augmented responses may be assumed to be mediated by the activation of helper T cells recognizing ATF1011 as a carrier protein. Killer T cells were induced against ATF1011 antigen in the H-2 restricted manner using syngeneic stimulator cells bearing ATF1011 on the cell surfaces. When this lectin was administered intralesionally into the tumors, induction of cytotoxic effector cells was demonstrated. These results suggest that intralesionally administered ATF1011 binds to the tumor cell membrane and activates T cells specific for this carrier lectin in situ, which results in the augmented induction of systemic antitumor immunity.  相似文献   
993.
Summary The liquid from heat-treatment of an abalone, Haliotis discus hannai, which is normally discarded as waste, was found to contain a new glycoprotein antineoplastic agent. A fraction of the liquid obtained from chromatography that was 22% carbohydrate and 44% protein was injected locally or systematically into ICR mice or BALB/c mice inoculated s.c. with allogeneic sarcoma 180 or syngeneic Meth-A fibrosarcoma, and growth of the tumors was strongly inhibited. There was an optimum dose range for the inhibition of the growth of sarcoma 180, and optimum timing. The fraction did not have antitumor activity in T cell-deficient nude mice (CD-1 nu/nu or BALB/c nu/nu mice), and administration of carrageenan in vivo decreased its activity in ICR mice. This fraction activated the cytostatic activity of peritoneal and alveolar macrophages in vivo. These results suggest that the antitumor activity is not due to a direct toxic effect but to stimulation of a host-mediated response.  相似文献   
994.
Direct optical resolution of antiinflammatory drugs such as ibuprofen, ketoprofen, flurbiprofen, and tiaprofenic acid were attempted by high-performance liquid chromatography using tris(3,5-dimethylphenylcarbamate)s of cellulose and amylose as chiral stationary phases. Although ibuprofen was not sufficiently resolved, the other three 2-arylpropionic acids were completely resolved by amylose tris(3,5-dimethylphenylcarbamate). Ibuprofen was resolved as anilide derivative.  相似文献   
995.
Dihydroxyacetone (DHA) kinase was purified to electrophoretic homogeneity from methanol-grown Hansenula polymorpha CBS 4732. The enzyme was a dimer with a molecular weight of 150,000, and had an isoelectric point of 4.9. The enzyme was active toward DHA, and D- and L-glyceraldehydes as phosphorylation acceptors, and only ATP served as a donor. ADP inhibited the enzyme at a physiological concentration. Magnesium ion was essential for the activity and stability. Some other divalent cations can substitute in part the magnesium ion. The DHA kinases found in cells grown on methanol and glycerol were immunologically identical, but were different from those of other methylotrophic yeasts as shown by immunotitration. A mutant (204D) derived from the yeast, which could not grow on methanol or DHA but could so on glycerol, was deficient in DHA kinase. Glycerol kinase activity was found in glycerol-grown 204D cells as well as the parent strain.Abbreviation DHA dihydroxyacetone  相似文献   
996.
997.
Early and late primary IgM antibody responses of mice to Thy-1.1 antigens showed different antigenic and cellular requirements. We studied genetic controls of the early primary responses, which could be induced by subcellular thymocyte antigens independently of host T-cell activity. All Thy-1.2 mouse strains of Igh a(BALB/c and BC8), Igh-V aCb(BAB14), Igh d(AKR/Cum), Igh j(CBA/J, C3H/HeN, C3H.SW, and C3H.JK), and Igh n(NZB) definitely responded early to Thy-1.1 antigens from AKR/J (Igh d), A.Thy-1.1 (Igh e), or B10.Thy-1.1 (Igh b) mice or SD rats, whereas all strains of Igh b(C57BL/6, C57BL/10, B10.D2, B10.BR, B10.A, CB20 and CWB), Igh c(DBA/2), Igh e(A/J), and Igh o(C.AL20) responded poorly to the same antigens. This contrasts with the observation that both strains of Igh j(C3H/HeN) and Igh b(B10.BR) responded well at later times. As was the case for late responses, the matching of H-2 between donor and recipient resulted in early responses of exceptional quality in high-responder strains. It was concluded that under the influence of H-2, whose incompatibility between donor and recipient partially interferes with responses, early but not late primary Thy-1.1-specific antibody responses are selectively controlled by Igh-V or closely linked Ir gene(s) as a new V Hmarker.Abbreviations used in this paper Tl T cell-independent - TD T cell-dependent - PFC plaque-forming cell(s) - Igh immunoglobulin heavy chain - V H variable region of heavy chain - C H constant region of heavy chain  相似文献   
998.
Frequency distributions of various plasminogen phenotypes in Japanese and American white populations were studied using electrofocusing in polyacrylamide gels followed by zymography and immunofixation. Using a synthetic substrate, tosyl-lysine-alpha-naphthyl ester, for zymography allowed zymography and immunofixation to be performed sequentially on the same gel plate. By this method, a nonfunctional abnormal plasminogen variant, plasminogen Tochigi, was readily detected in both plasma and serum. The gene frequency of this abnormal variant in a Japanese population was 0.018, whereas the abnormal variant was not detected in an American white population, suggesting the very rare occurrence of this variant in whites. Two common alleles, A and B, clearly identified in neuraminidase-treated samples, were observed at gene frequencies of 0.98 and 0.003, respectively, in the Japanese. These values are significantly different from the reported values in whites of 0.69 for A and 0.3 for B.  相似文献   
999.
Neutralization of Chlamydia (C.) psittaci avian strain P-1041 was examined in vitro using monoclonal antibodies (MAbs). Of the 10 MAbs used, 6 were found to exhibit neutralizing capability. These include 3 against major outer membrane protein (MOMP), 1 against lipopolysaccharide (LPS) and 2 against other protein molecules [90 kilodalton (kDa) and 90/50 kDa]. Most neutralizing MAbs were dependent on complement for efficient neutralization, while a strain-specific MAb (2B5) against the 90 kDa protein displayed a different requirement for complement and neutralized the infectivity of the P-1041 at high concentrations without complement. By competitive inhibition enzyme-linked immunosorbent assay (competitive inhibition ELISA), all 3 neutralizing anti-MOMP MAbs were demonstrated to recognize different epitopes found in very close proximity to each other on the outer membrane.  相似文献   
1000.
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