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31.
本文记述了采自吉林省白城草原的奥甲螨科Oppiidae 奥甲螨属Oppia一新种——白城奥甲螨Oppia baichengensis sp.nov.。对新种的形态特征进行了描述.并对新种与属内近似种作了比较鉴别。文内所用量度单位均为微米(μm)。 相似文献
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Ding Wen Wu John G. Duman 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,161(3):279-283
Summary Purified antifreeze proteins (AFPs) from the larvae of the beetle Dendroides canadensis do not produce the high levels of antifreeze activity seen in the hemolymph of overwintering larvae, even when the purified AFPs are assayed at very high concentrations. However, addition of certain proteins or agar (at concentrations sufficiently low that the gel state does not result) to the Dendroides AFP resulted in a 2–3-fold increase in activity. A 70-kDa protein with AFP-activating capabilities was purified from Dendroides larvae. Addition of this endogenous activator protein to a 4 mg·ml-1 solution of AFP increased the activity of the AFPs to values comparable to those of the hemolymph of overwintering larvae. Data derived from a modified immunoblot technique demonstrate that the activators bind to the AFP, or vice versa. Formation of this association must allow the AFP to block ice crystal growth by binding to the surface of potential seed crystals in the normal fashion. However, because the AFP-activator complex is much larger than the AFP alone, the complex probably blocks a greater surface area of the crystal and is thus a more efficient antifreeze.Abbreviations
AFP
antifreeze protein
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BSA
bovine serum albumine
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DEAE
diethylaminoethyl
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Ig
immunoglubolin
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LPIN
lipoprotein ice nucleator
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PIN
protein ice nucleator
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SDS
sodium dodecyl sulfate
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PAGE
polyacrylamide gel electrophoresis
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TH
thermal hysteresis 相似文献
35.
滇紫草愈伤组织培养与紫草素产生 总被引:9,自引:1,他引:8
浓度为10~(-5)Smol/1和10~(-6)mol/l的2,4-D和NAA分别与10~(-5)mol/l的KT组合,能明显抑制滇紫草(Onosma paniculatum Bur. et Fr.)愈伤组织中紫草素的产生,但几乎不受天然生长素IAA和KT组合的影响。葡萄糖较蔗糖能更有效地促进紫草素的产生,它们的最适浓度均为6%。LH和CH能抑制紫草素的产生,CH浓度大于0.02%时能抑制愈伤组织的生长,LH对生长无明显影响。椰乳浓度为10%时,能明显地促进紫草素的产生,紫草素的含量是对照的24倍。 相似文献
36.
Stephen G. Swisher Timothy M. Anderson Duan-Ren Wen Mark A. Stene Alistair J. Cochran Sidney H. Golub E. Carmack Holmes 《Cancer immunology, immunotherapy : CII》1991,33(5):327-332
Summary We administered preoperative low-dose interleukin-2 (IL-2) to 10 patients undergoing thoracotomy for pulmonary tumors. The in vivo effect of IL-2 on tumor-associated lymphocyte activity was assessed in the resected specimens by immunohistochemistry and compared with observations in 45 patients who did not receive IL-2. H & E evaluation revealed an increase in intra- and peritumoral lymphocyte infiltration in the IL-2-treated patients. Immunopathological evaluation with monoclonal antibodies revealed that this lymphocyte infiltration was predominantly CD5-positive T cells. The amount of intra-and peritumoral lymphocyte activity correlated with the dose of IL-2 administered (6000–90 000 international units/kg every 8 h for 48 h. IL-2-treated patients showed increases in T-cell-associated activation markers (IL-2 -receptor, transferrin receptor and HLA-DR) on peritumoral lymphocytes, but not on intratumoral lymphocytes. We previously reported that low-dose IL-2 increases the intrinsic natural killer cell cytotoxicity of intratumoral lymphocytes and suggest that this lymphocyte infiltration is further evidence that low-dose IL-2 can augment in vivo lymphocyte activity at the tumor site.This work was supported in part by USPHS grants CA 44 352 (S. H. G.) and 43 658 (A. J. C.). S. G. S. was supported by NIH Surgical Oncology Training Grant CA 09 010 相似文献
37.
给完整的及切除肾上腺的雌性 Wistar 大鼠分別注射地塞米松、去氧皮质酮或地塞米松加去氧皮质酮;冷酚法提取心房总 RNA,用α-~(32P)标记的大鼠心房肽 cDNA 探针与之杂交。完整大鼠接受地塞米松和切除肾上腺后接受地塞米松加去氧皮质酮的大鼠,心房肽基因转录产物增加2倍,其余组无显著变化。结果提示糖皮质激素可促进心房肽基因表达,但此作用依赖于盐皮质激素的同时存在,单纯盐皮质激素不能增强该基因的表达。 相似文献
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E Koren C Knight-Gibson G Wen L E DeBault P Alaupovic 《Biochimica et biophysica acta》1986,876(1):101-107
Monoclonal antibody ('Pan B' antibody) that binds equally to all major forms of human plasma apolipoprotein B was used in an immunoaffinity chromatography procedure to isolate apolipoprotein B-containing lipoproteins from hyperlipidemic human plasma. These lipoproteins were compared with lipoproteins in native plasma, with lipoproteins isolated by polyclonal antibodies and with lipoproteins isolated by the conventional ultracentrifugational method. Judged by the apolipoprotein and lipid composition, lipoproteins isolated with 'Pan B' antibody were virtually identical to those isolated by ultracentrifugation or polyclonal antibodies. Lipoproteins isolated by 'Pan B' antibody were comparable in size and shape to the lipoproteins in native plasma and to the lipoproteins isolated by polyclonal antibodies or ultracentrifugation. The immunoaffinity column with monoclonal 'Pan B' antibody retained all apolipoprotein B-containing lipoproteins and showed significantly higher capacity than polyclonal immunoaffinity column. The column with the highest capacity allowed the isolation from whole plasma of 0.144 mg of apolipoprotein B per ml of gel in less than 2 h. 相似文献
40.
The effects of anisodamine on the polymorphic phase behaviour of cardiolipin and dioleoylphosphatidylcholine liposomes have been investigated by freeze-fracture electron microscopy. Anisodamine induces the formation of lipidic particles in cardiolipin liposomes at pH 7.0 and hexagonal HII tubes at pH 8.8. When the molar ratio of anisodamine and dioleoylphosphatidylcholine is 4 to 1, lipidic particles can be observed in the fracture faces. 相似文献