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991.
992.
利用SDS-PAGE和A-PAGE方法对获得的遗传稳定性逐年提高节节麦-黑麦双二倍体的麦谷蛋白和麦醇溶蛋白进行了分析.结果显示:在高分子量谷蛋白区域,双二倍体共检测到3条带,其中第1和第3条带与亲本节节麦的5t和10t亚基大小一致,中间的第2条带是两亲本都未出现的新麦谷蛋白条带,而黑麦的2r和6.5r亚基在双二倍体材料中未检测到;在低分子量谷蛋白区域,黑麦和节节麦分别有4条和2条带在双二倍体材料中未检测到.在醇溶蛋白的γ和β区,黑麦共有5条带在双二倍体材料中未检测到,在ω区,节节麦有1条带未检测到.研究表明,在双二倍体中两亲本控制贮藏蛋白的基因组之间发生了较大的改变,与亲本节节麦相比较,亲本黑麦控制的贮藏蛋白发生的改变更大;两亲本控制贮藏蛋白基因的遗传方式在双二倍体材料中表现为非加性效应.  相似文献   
993.
记述坦小叶蝉属9新种,中国1新纪录种和1新组合,确认了1新异名,编制了中国坦小叶蝉属种检索表。模式标本均保存于西北农林科技大学昆虫博物馆。  相似文献   
994.
本文对韩国中华按蚊、雷氏按蚊和八代按蚊核糖体DNA (rDNA)内转录间隔 2区 (ITS2 )序列进行了比较研究。用PCR扩增的rDNA ITS2片段直接测序 ,每种蚊测定 3个个体 ,结果显示 :韩国中华按蚊、雷氏按蚊和八代按蚊的rDNA ITS2序列长度分别为 4 6 8bp、 4 51bp和 4 53bp ,GC含量分别为 4 4 .87%、 4 6 .2 %和 4 5.7% ,3种按蚊序列差异范围为 12 .16 %— 30 .74 %。研究表明 ,rDNA ITS2序列差异可用于韩国中华按蚊、雷氏按蚊和八代按蚊的分子鉴别。  相似文献   
995.
The objective of this work was to determine whether metabolic fingerprinting of spent bovine embryo culture media using Fourier transform infrared spectroscopy (FTIR) correlates with embryonic sex. Embryos were produced in vitro from oocytes collected from cows slaughtered in an abattoir. Day-6 embryos were individually cultured in synthetic oviduct fluid for 24 h, prior to the time (Day-7) intended for embryo transfer or cryopreservation. Culture medium was analyzed by FTIR. Embryos were sexed by a PCR procedure based on amelogenin gene amplification or transferred to a recipient and sex observed at birth. Media samples from embryos diagnosed as male (n = 47) or female (n = 70) were individually collected and evaluated using FTIR. The spectra obtained were analyzed according to metabolomic profile of embryo culture media and embryonic sex. The discrimination capability of the classifiers was assessed for accuracy, sensitivity (female), sensitivity (male) and area under the ROC curve (AUC). Performance of sex prediction (%) was high within early blastocysts + blastocysts (74.4 ± 10.2, accuracy; 0.749 ± 0.099, AUC) and excellent for expanded blastocysts (86.0 ± 12.6, accuracy; 0.898 ± 0.094, AUC). A combination of metabolomic and bioinformatic analysis provides a non-invasive mean of embryonic sex analysis.  相似文献   
996.

Purpose

Life cycle assessment (LCA) has been increasingly implemented in analyzing the environmental performance of buildings and construction projects. To assess the life cycle environmental performance, decision-makers may adopt the two life cycle impact assessment (LCIA) approaches, namely the midpoint and endpoint models. Any imprudent usage of the two approaches may affect the assessment results and thus lead to misleading findings. ReCiPe, a well-known work, includes a package of LCIA methods to provide assessments on both midpoint and endpoint levels. This study compares different potential LCIA results using the midpoint and endpoint approaches of ReCiPe based on the assessment of a commercial building in Hong Kong.

Methods

This paper examines 23 materials accounting for over 99 % of the environmental impacts of all the materials consumed in commercial buildings in Hong Kong. The midpoint and endpoint results are compared at the normalization level. A commercial building in Hong Kong is further studied to provide insights as a real case study. The ranking of impact categories and the contributions from various construction materials are examined for the commercial building. Influence due to the weighting factors is discussed.

Results and discussion

Normalization results of individual impact categories of the midpoint and endpoint approaches are consistent for the selected construction materials. The difference in the two approaches can be detected when several impact categories are considered. The ranking of materials is slightly different under the two approaches. The ranking of impact categories demonstrates completely different features. In the case study of a commercial building in Hong Kong, the contributions from subprocesses are different at the midpoint and endpoint. The weighting factors can determine not only the contributions of the damage categories to the total environment, but also the value of a single score.

Conclusions

In this research, the midpoint and endpoint approaches are compared using ReCiPe. Information is whittled down from the inventories to a single score. Midpoint results are comprehensive while endpoint results are concise. The endpoint approach which provides additional information of damage should be used as a supplementary to the midpoint model. When endpoint results are asked for, a LCIA method like ReCiPe that provides both the midpoint and endpoint analysis is recommended. This study can assist LCA designers to interpret the midpoint and endpoint results, in particular, for the assessment of commercial buildings in Hong Kong.  相似文献   
997.
Evolving evidence supports that cyclooxygenase-1 (COX-1) takes part in colon carcinogenesis. The effects of COX-1 inhibition on colon cancer cells, however, remains obscured. In this study, we demonstrate that COX-1 inhibitor sc-560 inhibited colon cancer cell proliferation with concomitant G0/G1-phase cell cycle arrest. The anti-proliferative effect was associated with down-regulation of c-Fos, cyclin E2 and E2F-1 and up-regulation of p21Waf1/Cip1 and p27Kip1. In addition, sc-560 induced macroautophagy, an emerging mechanism of tumor suppression, as evidenced by the formation of LC3+ autophagic vacuoles, enhanced LC3 processing, and the accumulation of acidic vesicular organelles and autolysosomes. In this connection, 3-methyladenine, a Class III phosphoinositide 3-kinase inhibitor, significantly abolished the formation of LC3+ autophagic vacuoles and the processing of LC3 induced by sc-560. To conclude, this study reveals the unreported relationship between COX-1 and proliferation/macroautophagy of colon cancer cells.  相似文献   
998.
999.
1000.
This study examines the effect of mutation of the low-density lipoprotein receptor (LDLR) on cholesterol metabolism, and especially lipoprotein-derived cholesteryl ester uptake, in murine ovarian granulosa cells. Although the tests were conducted on cells prepared by two different procedures, the results are similar. Deletion of LDLR function did not noticeably affect key enzymes of the steroidogenic pathway or affect progestin production and secretion in granulosa cells. No change was found in expression of LDL-related protein (LRP). These data suggested that cholesterol turnover in cells from the knockout animals is within normal limits and that the cells are not stressed to acquire more cholesterol. Both biochemical and morphological data indicate that unstimulated granulosa cells from LDLR−/− mice are nonetheless programmed to take in double the amount of lipoprotein-derived cholesteryl ester (via the selective cholesteryl ester uptake pathway) and to process (hydrolyze, re-esterify, or utilize) more than twofold the cholesteryl ester processed by cells from wildtype (LDLR+/+) animals. Bt2cAMP stimulation of the murine granulosa cells increases the mass of cholesteryl ester taken up by the selective pathway by an additional 38%. To determine to what extent this increase is related to high-density lipoprotein (HDL) scavenger receptor protein (SR-BI) or caveolin function, Western blots and immunohistochemical studies were performed under a variety of conditions. SR-BI levels are found to be low in unstimulated cells of both LDLR+/+ and LDLR−/− animals, but highly expressed (∼20-fold increase over basal levels) in stimulated (Bt2cAMP) cells of both animal models. Thus, the functional relationship between selective cholesteryl ester uptake and SR-BI receptor protein is not as tight as in previously reported studies, suggesting a requirement for other tissue factors. Caveolin expression did not change under any of the conditions tested and appears not to be functionally involved in this process. J. Cell. Physiol. 180:190–202, 1999. Published 1999 Wiley-Liss, Inc.  相似文献   
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