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141.
L. Yuan Yasuhiro Kuramitsu Yongqin Li Masanobu Kobayashi M. Hosokawa 《Cancer immunology, immunotherapy : CII》1996,41(6):355-362
We studied mechanisms of immunosuppression caused by tumor-derived transforming growth factor-β (TGFβ) and restoration of
the immune response by treatment with bleomycin in rats bearing KDH-8 hepatoma. Interleukin-2 (IL-2) production from splenocytes
of KDH-8-tumor-bearing rats progressively decreased as the KDH-8 tumor grew. IL-2 production from concanavalin-A-stimulated
normal rat splenocytes was signficiantly inhibited by in vitro cultured KDH-8-tumor-cell-conditioned medium; this inhibition
could be blocked by neutralizing the conditioned medium with anti-TGFβ antibody. TGFβ activities were found in KDH-8-tumor-tissue-conditioned
medium without acid treatment and were found in tumor-cell-conditioned medium after acid treatment; TGFβ mRNA and TGFβ protein
were found in cultured KDH-8 tumor cells. These results suggested that the KDH-8-tumor-derived TGFβ might be involved in the
inhibition of IL-2 production from splenocytes. To determine whether bleomycin chemotherapy could reduce tumor-derived TGFβ
and restore the immune responses, we treated KDH-8 tumor-bearing rats with bleomycin (5 mg/kg, one shot) at an appropriate
time (before the occurrence of immunosuppression) resulting in a significiant reduction of TGFβ activity in KDH-8 tumor tissues
and restoration of IL-2 production from splenocytes of tumor-bearing rats; KDH-8 tumor growth ultimately regressed. In vitro
experiments also showed that TGFβ activity, mRNA expression, and protein synthesis in KDH-8 tumor cells were reduced by bleomycin
treatment, and that bleomycin-treated-KDH-8-tumor-cell-conditioned medium did not inhibit IL-2 production from normal rat
splenocytes. These results suggest that bleomycin treatment restored IL-2 production in tumor-bearing rats through reducing
the tumor-derived TGFβ.
Received: 12 June 1995 / Accepted: 3 November 1995 相似文献
142.
Susumu Higuchi Taro Muramatsu Sachio Matsushita Masanobu Murayama Motoi Hayashida 《Human genetics》1996,97(4):431-434
Inactive aldehyde dehydrogenase-2 (ALDH2) is a well-known biological deterrent of heavy drinking among Asians, although some individuals who have inactive ALDH2 do become alcoholics. Unknown biological mechanisms facilitating the development of the disease may operate in such a way that these individuals overcome adverse reactions, or they may lower the intensity of the reactions. To examine our hypothesis that ethanol-oxidizing isoenzymes have lower catalytic properties in some persons, we investigated polymorphisms of ethanol-oxidizing enzymes that may alter their catalytic activities, viz., alcohol dehydrogenase-2 (ADH2) and –3 (ADH3), and cytochrome P450 2E1 (CYTP2E1), among 80 Japanese alcoholics with inactive ALDH2, 575 alcoholics with active ALDH2, and 461 controls. Although higher ADH2*1 and ADH3*2 allele frequencies were observed in alcoholics than in controls, there was no significant difference in ADH2 and ADH3 genotypes between alcoholics with inactive ALDH2 and alcoholics with active ALDH2. The genotype distributions of CYTP2E1 did not differ among the three groups, indicating no allelic association of the c1/c2 polymorphism of CYTP2E1 with alcoholism. These results suggest that genetic variations in ethanol-oxidizing activities are involved in the development of the disease, but that these variations are not specific in alcoholics with inactive ALDH2, a group at genetically low risk for alcoholism. 相似文献
143.
Masanobu Kawachi Misako Kato Hisato Ikemoto Shigetoh Miyachi 《Journal of applied phycology》1996,8(4-5):397-401
A marine yellowish picoplankton, strain PP301, which was newly isolated from the surface seawater of the western Pacific Ocean was an eminent producer of polyunsaturated fatty acids. Its fatty acids were mostly shared by the shortest saturated form (14:0, 20–30%) and polyunsaturated forms (20:4, EPA and DHA) which accounted for about 50% of the total fatty acids. The amount of intermediate forms in 16 and 18 carbon chains were very little. This composition was consistently observed irrespective of the growth temperatures (15–35 °C). 相似文献
144.
L. Yuan Masanobu Kobayashi Yasuhiro Kuramitsu Yongging Li Kazushiro Matsushita M. Hosokawa 《Cancer immunology, immunotherapy : CII》1997,45(2):71-76
To explore the mechanisms of immuno-modulatory activities of bleomycin, we investigated interferon γ (IFNγ) mRNA expression,
tumor necrosis factor α (TNFα) production, nitric oxide (NO) production and macrophage tumoricidal activities in rats bearing
KDH-8 hepatoma cells, which secreted a large amount of transforming growth factor β (TGFβ), and these processes in KDH-8 tumor-bearing
rats treated with bleomycin. We found that IFNγ mRNA expression, TNFα production, NO production and macrophage cytotoxic activities
were lower in the KDH-8-bearing rats than in normal rats. On the other hand, low-dose bleomycin restored the macrophage cytotoxic
activities, NO production, IFNγ mRNA expression and TNFα production in the KDH-8-bearing rats. In vitro experiments showed
that KDH-8-derived TGFβ decreased the IFNγ mRNA expression and TNFα production in splenocytes, and NO production in peritoneal
macrophages. These results suggest that low-dose bleomycin restored the cytokine production and macrophage tumoricidal activities
in the KDH-8-bearing rats by decreasing KDH-8-derived TGFβ.
Received: 14 October 1996 / Accepted: 22 July 1997 相似文献
145.
146.
High‐speed videography and inverted light microscope observations of cultures of several Pyramimonas Schmarda species (Pyramimonas chlorina Sym et Pienaar, Pyramimonas disomata McFadden Hill et Wetherbee, Pyramimonas gelidicola McFadden Wether‐bee et Moestrup, Pyramimonas mantoniae Moestrup et Hill, Pyramimonas melkonianii Sym et Pienaar, Pyramimonas mitra Moestrup et Hill, Pyramimonas moestrupii McFadden, Pyramimonas mucifera Sym et Pienaar, Pyramimonas nephroidea McFadden, Pyramimonas orientalis McFadden Hill et Wetherbee, Pyramimonas parkeae Norris et Pearson, Pyramimonas propulsa Moestrup et Hill) revealed swimming behavior to be much more diverse than originally reported for the genus. This diversity shows gradation between extremes of recurved flagellar beating and non‐biphasic ciliary beating. Comparison with the behavior of presumably more primitive members of the Pyramimonadales (Cymbomonas tetramitformis Schiller and Pterosperma cristatum Schiller) leads to the conclusion that the former condition is primitive and the gradation may assist in reconstructing phylogenetic relationships within the genus Pyramimonas, particularly as it is consistent with phylogenies derived from ultrastructural and molecular data. 相似文献
147.
148.
149.
Masanobu Kitagawa Yoshio Kuwashima Tetsuo Nemoto Sachiko Seki Osamu Matsubara Tsutomu Kasuga 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,58(1):365-370
The dynamics of lymphoid cell subpopulations in bronchoalveolar lavage fluid (BALF) and the systemic lymphoid organs of mice
after intravenous injection of B16 melanoma cells were examined with a fluorescence-activated cell sorter. The lymphoid cell
subpopulations of BALF and mediastinal lymph nodes showed significant changes in numbers and proportions, while those of other
lymphoid organs including inguinal lymph nodes, thymus and spleen, showed little change. In week 1, the cells with a Thy-1.2+, Lyt-1+, L3T4−, Lyt-2− phenotype and asialo-Gm1+ cells in BALF significantly increased and L3T4+ cells slightly increased in number. By week 3, the numbers of Lyt-2+ cells in BALF markedly increased in number (by about 90 times) compared with controls. The number of Thy1.2+ cells in mediastinal lymph nodes also increased significantly by week 3. Mice that had been pretreated with an immunosuppressive
dose of cyclophosphamide were also inoculated intravenously with B16 melanoma cells. In these mice, a significantly increased
number of pleural tumors developed and the number of Thy-1.2+ cells in BALF was markedly reduced from week 1 to 3. The results indicate that L3T4 and Lyt-2 double negative T-cells and
natural killer (NK) cells may be generated and/or mobilized to the lung in an early phase of experimental metastasis of B16
melanoma cells and that at a later stage, when multiple metastases develop, T-cells with a Lyt-2+ phenotype markedly increase, probably as an expression of a host reaction against proliferating metastatic tumor cells. 相似文献
150.
Chromosomal damage in peripheral blood lymphocytes of patients treated for testicular cancer 总被引:3,自引:3,他引:0
Eva van den Berg-de Ruiter Bauke de Jong Nanno H. Mulder Gerard J. te Meerman Heimen Schraffordt Koops Dirk T. Sleijfer 《Human genetics》1990,84(2):191-194
Summary We describe the presence of a large number of chromosome aberrations in lymphocytes of 50 patients with testicular cancer. These chromosomal aberrations were not only found in patients treated with chemotherapy but also in untreated patients or in patients after surgery alone. Our results suggest a role for genetic instability in the pathogenesis of testicular cancer. This instability might be a risk factor for the development of secondary malignancies. 相似文献