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871.
872.
Toward cataloguing all rice genes: large-scale sequencing of randomly chosen rice cDNAs from a callus cDNA library 总被引:17,自引:0,他引:17
Takuji Sasaki Jianyu Song Yasunori Koga-Ban Eriko Matsui Fang Fang Hiromi Higo Hideki Nagasaki Maki Hori Mikiko Miya Eiko Murayama-Kayano Tomoko Takiguchi Akiko Takasuga Tomoya Niki Ken Ishimaru Hrioshi Ikeda Yoshihisa Yamamoto Yoshiyuki Mukai Isamu Ohta Nobuo Miyadera Ilkka Havukkala Yuzo Minobe 《The Plant journal : for cell and molecular biology》1994,6(4):615-624
873.
Masayoshi Kumegawa Taishin Takuma Satoko Hosoda Michie Nakanishi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,587(1):20-27
The hormonal requirements for formation of tyrosine aminotransferase (EC 2.6.1.5) in fetal mouse liver were investigated in organ culture using chemically defined medium. The hormones tested were insulin, thyroxine and prednisolone. Prednisolone alone resulted in a two-fold increase in tyrosine amino-transferase activity in explanted liver in hormone-free medium on day 6, and its effect was dose dependent, but neither insulin nor thyroxine alone induced the enzyme. Addition of prednisolone plus thyroxine and prednisolone plus insulin increased the enzyme activity 1.4- and 1.3-fold, respectively, over that of explants with prednisolone alone. These three hormones together had the greatest effect, causing induction of 1.5-fold more activity than that with prednisolone plus insulin or plus thyroxine. The three hormones were not all needed continuously during the culture period: prednisolone and insulin were required during the early part of cultivation and thyroxine during the later part. The effects of these hormones were blocked by actinomycin D or puromycin, suggesting that these hormones increase de novo synthesis of tyrosine aminotransferase. Phase-contrast microscopy showed that prednisolone stimulated liver epithelial cell outgrowth, probably acting with insulin. 相似文献
874.
875.
Application of matrix-assisted laser desorption ionization time-of-flight mass spectrometry with delayed ion extraction to ganglioside analyses 总被引:3,自引:1,他引:2
Various monosialo- and disialo-gangliosides and their derivativeswere examined by delayed ion extraction matrix-assisted laserdesorption ionization time-of-flight mass spectrometry (DE MALDI-TOFMS) in the reflector mode with 相似文献
876.
Experiments were conducted to answer the questions related to (a) the role played by the antigen-presenting cells (APCs) present within the thymus and (b) the effect of radiation dose to the recipients on the H-2 restriction profile of TNP-specific cytotoxic T lymphocyte precursors (CTLP) recovered from spleens and/or thymuses of H-2 incompatible radiation bone marrow chimeras (BMC). The H-2 restriction profile of intrathymically differentiating TNP-specific CTLPs was also analyzed in order to test an argument that donor-H-2 restricted CTLP detected in spleens of H-2 incompatible BMC were due to the extrathymically differentiated T cells under the influence of donor-derived lymphoreticular cells. The results indicated the following: (i) splenic T cells from B10(H-2b)→ (B10(H-2b) → B10.BR(H-2k)) chimeras, which were constructed by irradiating primary BIO → B10.BR chimeras with 1100 R and reconstituting them with donor-type (B10) bone marrow cells as long as 8 months after their construction, manifested restriction specificities for both donor- and host-type H-2, (ii) splenic T cells from two types of (B10 × B10.BR)F1→ B10 chimeras which were reconstituted after exposure of the recipients with either 900 or 1100 R with donor-type bone marrow cells generated both donor- and host-H-2 restricted TNP-specific cytotoxic T cells, and (iii) the TNP-specific CTLPs present in the regenerating thymuses of B10.BR → B10 and (B10 × B10.BR)F1→ B10 chimeras 4 weeks after their construction were also shown to manifest both donor- and host-H-2 restriction specificities. The significance of these findings on the H-2 restriction profile of CTLP generated in BMCs is discussed. 相似文献
877.
Hirofumi Shimomura Kouichi Hosoda Shunji Hayashi Kenji Yokota Keiji Oguma & Yoshikazu Hirai 《FEMS microbiology letters》2009,301(1):84-94
Helicobacter pylori assimilates various steroids as membrane lipid components, but it can also survive in the absence of steroids. It thus remains to be clarified as to why the organism relies on steroid physiologically. In this study, we have found that phosphatidylcholine carrying a linoleic acid molecule or arachidonic acid molecule has the potential to kill steroid-free H. pylori . The bactericidal action of phosphatidylcholines against H. pylori was due to the lytic activity of the phosphatidylcholines themselves and not due to the lytic activity of the unsaturated fatty acids or lyso-phosphatidylcholine resulting from the hydrolysis of the phosphatidylcholines. In contrast to the steroid-free H. pylori , the organism that absorbed and glucosylated free cholesterol was unaffected by the bactericidal action of the phosphatidylcholines. Similarly, H. pylori that absorbed estrone without glucosylating it also resisted the bactericidal action of the phosphatidylcholines. The steroids absorbed by H. pylori existed in both the outer and inner membranes, while the glucosyl-steroids produced via the steroid absorption were localized in the outer membrane rather than in the inner membrane. These results indicate that H. pylori absorbs the steroids to reinforce the membrane lipid barrier and thereby expresses resistance to the bacteriolytic action of hydrophobic compounds such as phosphatidylcholine. 相似文献
878.
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