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11.
拉萨郊区藏族跖纹主线走向分析 总被引:4,自引:1,他引:3
本文用茚三酮-味精法采集跖纹,体视显微镜下追踪跖纹主线走向,分析了250(男女各125人)拉萨效区藏族健康人的跖纹样本。结果显示:A线主要走向1区,其次是7区;B线亦多止于1区和7区;C线主要止于和9区;D线止于1区 频率最高;E线主要走向13区;P三叉缺失较多。Pz^d线止共位置较高(13区和11区),而P^f线止区较低(7区)。在民族和人种间进行了比较,提示藏族践纹主线走向有自己的特点,又呈现 相似文献
12.
H. -P. Piepho 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(5):647-654
Multilocation trials are often used to analyse the adaptability of genotypes in different environments and to find for each environment the genotype that is best adapted; i.e. that is highest yielding in that environment. For this purpose, it is of interest to obtain a reliable estimate of the mean yield of a cultivar in a given environment. This article compares two different statistical estimation procedures for this task: the Additive Main Effects and Multiplicative Interaction (AMMI) analysis and Best Linear Unbiased Prediction (BLUP). A modification of a cross validation procedure commonly used with AMMI is suggested for trials that are laid out as a randomized complete block design. The use of these procedure is exemplified using five faba bean datasets from German registration trails. BLUP was found to outperform AMMI in four of five faba bean datasets. 相似文献
13.
14.
油菜主序优势及其利用初析 总被引:2,自引:0,他引:2
油菜具有主序优势,主要表现在结角数上,在角粒数、千粒重及品质上也很显著。不同类型其优势强弱不同,白菜型和甘蓝型优势明显,芥菜型几乎不具有优势。在甘蓝型油菜中因品种、密度不同优势差异显著。增加密度可使主序在产量中的比例增加,在5万株/亩时可达73.05%.主序具有结角率高、成熟早等优点,通过选育优势强的品种,适当增加密度,合理调整布局,有望使油菜产量有较大幅度地提高 相似文献
15.
Xiaoliang Liu Akemi Ota Michiko Watanabe Shigeharu Ueda Atsushi Saitoh Hideo Shinagawa Atsuo Nakata Takashi Kurimura Xiaoui Wang Yu Zhao Kiyoshi Kondo Jiro Seki Shinichi Miyake Nobuo Sakato Hajime Fujio 《Microbiology and immunology》1995,39(10):775-785
We investigated the murine antibody response to recombinant p17 (rp17) of human immunodeficiency virus type 1 (HIV-1) and the human antibody response directed to p17 in HIV-1 infection. Three large peptides covering residues 12-29, 53-87 and 87-115 of p17 were synthesized. The cysteine residues 57 and 87 of peptide 53-87 were reoxidized to form a disulfide bridge. Eighteen out of 19 murine monoclonal anti-rp17 antibodies had relatively high affinities (KA = 1.9 × 105?1.4 × 108 M?1) with one of the 3 p17 peptides in the liquid phase. Each monoclonal antibody reacted only with one particular peptide and had no reactivity with the other 2 p17 peptides. All the monoclonal antibodies reacted with rp17 in the liquid phase with a reasonable degree of affinity (KA = 2.0 × 105?1.8 × 107 M?1). Four HIV-1 carrier sera, which were positive in ELISA using rp17 as the antigen, reacted positively in an ELISA using 3 p17 peptides which were used to titrate murine monoclonal antibodies. Murine monoclonal antibodies having specificity for the 3 p17 peptides stained live HIV-1-infected cells by means of indirect membrane immunofluorescence, irrespective of their specificity. This suggests that the various portions of p17 (at least 3 regions of p17) were exposed on the surface of live infected cells, probably as short polypeptide chains. 相似文献
16.
The VP1 coat protein of FMDV strain A Venceslau (Aven) consists of 213 amino acid residues. Serum neutralization tests demonstrated that strain Aven is closely related to strain A Argentina/79 (A79) but significantly different from strain A24 Cruzeiro (A24). There is a strong correlation between the amino acid sequences and the serological data. Nucleotide and amino acid sequence analyses of VP1 showed that serologically related viruses (Aven and A79) differ less in this region of the genome than those of serologically distinct viruses (Aven vs. A24). The most significant variation between Aven and A24 occurs at amino acid positions 43 to 46, in which all four residues are different. 相似文献
17.
The quantity of thymus-leukemia (TL) antigens expressed by murine leukemia cells is significantly greater than that expressed by somatic hybrids of such cells. Based upon the results of 125I-lactoperoxidase labeling and antibody absorption procedures, and corrected for size differences between the two cell types, the quantity of TL antigens expressed by RADA-1 cells, a radiation-induced murine leukemia cell line of strain A/J mice, is approximately 5.0 times greater than that of somatic hybrids of RADA-1 and LM(TK)? cells. LM(TK)? cells are a thymidine kinase-deficient TL(-) mouse fibroblast cell line. The quantity of TL antigens expressed is related only in part to their susceptibility to lysis by TL antibodies and guinea pig complement (GPC). RADA-1 cells resist lysis. The quantity of TL antigens expressed by RADA-1 cells is analogous to that formed by nonneoplastic thymocytes obtained from F1 hybrids of two strains of TL(+) and TL(-) mice; cells from both strains are sensitive to TL antiserum and GPC. ASL-1 cells, a spontaneously occurring leukemia cell line of A/J mice, express TL antigens in significantly higher quantities than any of the cell types examined. Exposed to TL antisera, the quantity of TL antigens of ASL-1 cells, but not that of hybrid cells, gradually diminishes. ASL-1 cells convert over a 6-h period of exposure to antibody and guinea pig complement (GPC) resistance; hybrid cells remain sensitive. However, ASL-1 cells converted to TL antibody and GPC resistance continue for a time to express TL antigens in quantities similar to that of sensitive F1 thymocytes and resistant RADA-1 cells. RADA-1 X LM(TK)? hybrid cells, which are sensitive to TL antibodies and GPC, express the lowest quantities of TL antigens of any of the cell types examined. It is likely that differences in the quantities of TL antigens expressed by different cell lines reflect genetic mechanisms controlling TL antigen expression. The failure of TL antisera to affect the quantities of TL antigens expressed by hybrid cells is taken as an indication that genetic controls governing antigen expression may be distinguished from those involved in regulating responsiveness to specific antiserum. 相似文献
18.
Alicia Alonso Colin J. Restall Margaret Turner Juan C. Gomez-Fernandez Felix M. Goñi Dennis Chapman 《生物化学与生物物理学报:生物膜》1982,689(2):283-289
Bacteriorhodopsin has been reconstituted at various molar concentrations into liposomes of dimyristoyl- and also of dipalmitoylphosphatidylcholine. Differential scanning calorimetry indicates that as the protein concentration within the lipid bilayer increases, the cooperativity of the lipid phase transition is reduced, i.e. the transition is broadened, while the midpoint transition temperature remains virtually unchanged. Freeze-fracture electron microscopy of our preparation shows, in agreement with previous data from other laboratories, that extensive protein aggregation occurs when the liposome is cooled below the Tc transition temperature of the lipid. Laser flash photolysis measurements of protein rotation of the bacteriorhodopsin show, especially in the case of protein-rich recombinants, that protein aggregates exist even above Tc. The perturbation caused by the presence of bacteriorhodopsin in the lipid bilayer is similar to that produced by other intrinsic proteins. The difficulty of correlating the observed calorimetric enthalpy data with a simple concept of a ‘boundary lipid layer’ based upon consideration of a single isolated protein is discussed in view of the occurrence of protein aggregates both above and below Tc. It is concluded that the reduction of enthalpy is related to the number of lipids which solvate the protein aggregates within the protein-lipid patches and are thereby removed from the cooperative melting and enthalpy of the remaining regions of pure lipid. 相似文献
19.
本文对一株人抗人A-血型物质单克隆抗体,用定量免疫沉淀法以及ELISA研究其与多种单糖、双糖及寡糖的反应性,从而确定了其结合部位的结构特异性。实验发现其结合部位互补于含有双分子岩藻糖残基的A-t糖:这一研究进一步强调了含有双分子岩藻糖残基的A血型抗原决定簇的重要性。 相似文献
20.
Y D Karkhanis R L Anderson J Y Zeltner R Z Maigetter D J Carlo T H Stoudt 《Biochemical and biophysical research communications》1979,89(2):750-758
An antigenic subunit of molecular weight 66,000 daltons has been isolated from the antigenic complex of the Melvin strain of . Incubation of the complex in 8M urea at room temperature for four hours resulted in the dissociation of the subunit from the complex. It was separated from the complex by chromatography of the incubation mixture on a Sepharose 6B column in 50 mM ammonium bicarbonate pH 8.5 without 8M urea and further purified by affinity chromatography. This communication reports on a newly isolated antigenic protein devoid of LPS present in the bacteria. 相似文献