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161.
The antitumor activities of extracted polysaccharide fractions from the stems of Dendrobium nobile Lindl were investigated. Polysaccharides were sequentially extracted from the stems of D. nobile to obtain three fractions, i.e. water extract fraction (DNP-W), 5% NaOH extract fraction (DNP-OH) and 5% HCl extract fraction (DNP-H). Further the DNP-W was isolated to give six sub-fractions (DNP-W1, DNP-W2, DNP-W3, DNP-W4, DNP-W5 and DNP-W6) by anion-exchange chromatography. The monosaccharide profile, protein content, uronic acid content, total carbohydrate content, viscosity and molecular weight of nine polysaccharide fractions were analyzed. Both the in vivo and in vitro antitumor activities of nine polysaccharide fractions were evaluated and compared. Results indicated that DNP-W1 and DNP-W3 exhibited high antitumor activities against Sarcoma 180 in vivo and HL-60 in vitro. The results suggested that DNP-W1 and DNP-W3 could be considered as an effective natural antitumor source. 相似文献
162.
Daniel Bandarra Telma Lopes Marta S. Saraiva Carla D. Nunes Paula Brandão Margarida Meireles Maria José Calhorda 《Journal of inorganic biochemistry》2010,104(11):1171-1177
Several molybdenum complexes, [Mo(η3-C3H5)X(CO)2(N-N)] (N-N = 1,10-phenanthroline, phen: X = CF3SO3T1, X = Br B1, X = Cl C1; N-N = 2,2′-bipyridyl, X = CF3SO3T2, X = Br B2) and [W(η3-C3H5)Br(CO)2(phen)] (W1) have been synthesized and characterized. Their antitumor properties have been tested in vitro against human cancer cell lines cervical carcinoma (HeLa) and breast carcinoma (MCF-7) using a metabolic activity test (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, MTT), leading to IC50 values ranging from 3 to 45 μM, approximately. Most complexes exhibited significant antitumoral activity. Complexes B1 and T2 were chosen for subsequent studies aiming to understand their mechanism of action. Cellular uptake of molybdenum and octanol/water partition assays revealed that both B1 and T2 exhibit a selective uptake by cells and intermediate partition coefficients. The binding constants of B1 and T2 with ct DNA, as determined by absorption titration, are 2.08 (± 0.98) × 105 and 3.68 (± 2.01) × 105 M− 1, respectively. These results suggest that they interact with DNA changing its conformation and possibly inducing cell death, and may therefore provide a valuable tool in cancer chemotherapy. 相似文献
163.
164.
Ultraviolet light is the major cause of skin cancers in human, and several effects of ultraviolet light B (UVB) are thought to contribute to skin photocarcinogenesis. 3Beta-methoxy-13alpha,14alpha-epoxyserratan-21beta-ol (PJJ-34; 1) isolated from Picea jezoensis Carr. var. jezoensis showed the strongest antitumor-promoting activity among naturally occurring triterpenoids in the in vivo two-stage mouse skin-carcinogenesis test. To investigate the anti-initiating activity, we further studied mouse models initiated with ultraviolet-B (UVB) and promoted with 12-O-tetradecanoylphorbol-13-acetate (TPA). Oral administration of the PJJ-34 (1) during a period before and after the three times of UVB irradiation led to a remarkable effect: oral administration of a 0.0025% solution of 1 only to the test group, which started one week before and ended one week after the irradiation, showed less than half papillomas, and inhibition of tumor incidence and tumor multiplicity in comparison to the control group. Therefore, it was recognized that PJJ-34 (1) showed strong anti-initiating activity as well as anti-promoting activity. After all, 1 seems to be useful as cancer-chemopreventive agent. 相似文献
165.
Successful elimination of memory-type CD8+ T cell subsets by the administration of anti-Gr-1 monoclonal antibody in vivo 总被引:2,自引:0,他引:2
Matsuzaki J Tsuji T Chamoto K Takeshima T Sendo F Nishimura T 《Cellular immunology》2003,224(2):98-105
During investigating the expression of Gr-1 antigen on various subsets of mouse spleen cells, we found that Gr-1 was expressed on memory-type CD8(+)CD44(high)CD62L(high) T cells in addition to granulocytes. Intraperitoneal administration of anti-Gr-1 mAb caused almost complete elimination of Ly-6C(+) memory-type CD8(+) T cells as well as Ly-6G(+) granulocytes. Anti-Gr-1 mAb-treated mouse spleen cells exhibited greatly reduced IFN-gamma production in response to anti-CD3 mAb both in vitro and in vivo. This reduced cytokine production appeared to be derived from elimination of IFN-gamma-producing Gr-1(+)CD8(+) T cells. Indeed, CD8(+) T cells with IFN-gamma-producing activity and cytotoxicity were generated from isolated Gr-1(+)CD8(+) cells but not from Gr-1(-)CD8(+) T cells. We also demonstrated that therapeutic effect of MBL-2 tumor-immunized spleen cells was greatly reduced by anti-Gr-1 mAb-treatment. Thus, we initially demonstrated that anti-Gr-1 mAb might become a good tool to investigate a precise role for memory-type CD8(+) T cells in vivo. 相似文献
166.
The potent antitumor agent OSW-1 was synthesized from the protected aglycone in different ways. It was proven that direct glycosylation of the aglycone in its hemiketal form could be achieved, affording the protected OSW-1 in a moderate yield. Alternatively, regioselective protection of the triol obtained by reduction of the aglycone, followed by glycosylation, deprotection and oxidation yielded the same OSW-1 derivative. The third approach to this compound consisted of glycosylation of the previously described lactol [Morzycki, J. W.; Gryszkiewicz, A. Polish J. Chem. 2001, 75, 983-989], reaction of the resulting aldehyde with a Grignard reagent, and oxidation. OSW-1 obtained on removal of the protective groups was identical with the natural product. 相似文献
167.
Koji Tamada M. Harada Koichiro Abe Tieli Li Hitoshi Tada Yasuhiro Onoe Kikuo Nomoto 《Cancer immunology, immunotherapy : CII》1998,46(3):128-136
In order to enhance the antitumor vaccination effect of dendritic cells (DC) pulsed with class I tumor peptide, we tried
to utilize the local cytokine help of CD4+ T cells reactive to a streptococcal preparation OK432. DC were prepared from murine bone marrow cells by culture with both
granulocyte/macrophage-colony-stimulating factor and interleukin(IL)-4. The peritumoral injections of OK432 induced OK432-reactive
CD4+ T cells in the draining lymph nodes, and their in vitro production of interferon γ was thus significantly enhanced by restimulation
with OK432-pulsed DC. In addition, anti-P815 mastocytoma cytotoxic T lymphocytes were generated from the in vivo OK432-treated
P815-draining lymph node cells only when the lymph node cells were restimulated in vitro with the DC pulsed with both P1A
peptide and OK432. Moreover, the peritumoral injections of OK432 and the subsequent vaccination of the DC, pulsed with both
OK432 and P1A peptide, significantly suppressed the growth of s.c. inoculated P815. Interestingly, a significant level of
IL-12 was detected in the coculture supernatant of both OK432-pulsed DC and OK432-reactive CD4+ T cells. Collectively, our results suggest that the antitumor vaccination effect of DC pulsed with class I tumor peptide
could thus be effectively augmented by locally utilizing the Th1-type cytokines from OK432-reactive CD4+ T cells.
Received: 18 July 1997 / Accepted: 23 December 1997 相似文献
168.
Won-Jea Cho Eui-Ki Kim Myun-Ji Park Sang-Un Choi Chong-Ock Lee Seung Hoon Cheon Bo-Gil Choi Byung-Ho Chung 《Bioorganic & medicinal chemistry》1998,6(12):2449-2458
In this study a series of 3-arylisoquinoline derivatives were synthesized and cytotoxicity against human melanoma tumor cell evaluated, and a three dimensional quantitative structure—activity relationship was investigated using the comparative molecular field analysis (CoMFA). The results suggested that the electrostatic, steric and hydrophobic factors of 3-arylisoquinolines were strongly correlated with the antitumor activity. Considerable predictive ability (cross-validated r2 as high as 0.721) was obtained through CoMFA. 相似文献
169.
Christina M. Fleischmann G. John Stanton W. Robert Fleischmann Jr 《Cancer immunology, immunotherapy : CII》1994,39(3):148-154
Mouse B16 melanoma cells rapidly develop resistance to the antiproliferative effects of interferon (IFN) and interferon (IFN) when they are exposed to the interferons in vitro. This resistance was characterized to be non-genetic and dose-dependent, and does not alter other IFN-induced effects such as antiviral effects and elevation of 2,5-oligoadenylate synthetase activity in IFN-treated cells. The study of these IFN-resistant cells has been extended to an in vivo tumor model. Resistance, if it occurred in vivo, did not adversely affect the survival of IFN-treated mice. Further, IFN-treated mice inoculated with B16 cells that were resistant in vitro (B16res cells) survived significantly longer than IFN-treated mice inoculated with B16 cells that were sensitive in vitro. The IFN-treated B16res-inoculated mice had a significantly higher cure rate as well. The prolonged survival of the mice bearing B16res cell tumors did not seem to be caused by the slower growth rate of the B16res cells, since experiments performed with a tenfold higher B16res cell inoculum and a tenfold lower B16 cell inoculum did not show any change in the survival pattern. It is clear that in vitro resistant B16res cells are more sensitive to antitumor effects induced by IFN in vivo than in vitro sensitive B16 cells.Supported by U. S. Public Health Service grant no. CA50752 awarded by the National Cancer Institute, Department of Health and Human Services (W. R. F.) and by a James W. McLaughlin Fellowship (C. M. F.) 相似文献
170.
植物细胞培养生产抗癌药物研究进展 总被引:14,自引:1,他引:13
本文综述了国外通过植物细胞培养生产抗癌药物的进展情况。并着重介绍了长春碱、鬼臼毒素及紫杉醇的研究概况。 相似文献