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81.
AtHAK5是拟南芥高亲和性钾转运体,其基因表达受低钾条件强烈诱导,编码蛋白在低钾条件下可以整合到质膜.生物信息学分析发现其氨基酸序列含有多处潜在的磷酸化位点.本研究假设这些位点对于AtHAK5的功能至关重要,为探讨AtHAK5的功能位点,分别将AtHAK5 cDNA和带有13种不同点突变位点的AtHAK5转化到athak5突变体中,获得14种稳定表达的转基因植株.利用athak5突变体根对Cs敏感的表型,最终确定T549A和T666A为非核心磷酸化位点.如下11个位点为AtHAK5功能必需位点:F85L,T86A,T311A,T359A,P551S,D552N,S603A,S604A,K668E,S698A和V713L.  相似文献   
82.
中华穿山甲(Manis pentadactyla)属于全球极度濒危物种,也是我国一级保护动物。对中华穿山甲的非法捕杀曾导致其种群数量锐减。但是,近年来相关研究报道较少,穿山甲分布状况不明,极大地制约了对该物种的有效保护。搜集了近年来国内中华穿山甲的救护记录和救护新闻,甄别出67个记录分布点,利用最大熵模型软件(MaxEnt)进行因子筛选,结果表明最冷季度降水量、人口密度、年降水量、坡度、坡向、海拔等6个环境变量是与中华穿山甲分布显著相关的影响因子。基于6个主导环境变量构建的MaxEnt模型AUC平均值为0.961±0.014,预测结果达到极好标准。刀切法(Jackknife)表明,其中最冷季度降水量、年降水量、人口密度和海拔是影响中华穿山甲分布的主要因素。中华穿山甲适宜生境(出现概率大于0.498)具有以下特点:最冷季度降水量141.22-439.46 mm,年降水量1471.67-2386.56 mm,人口密度≥390人/km2,海拔<316.98 m。该模型预测中华穿山甲在我国的潜在分布适宜区主要位于我国长江以南地区,总面积约为74.27×104 km2,占国土面积的7.73%,主要集中在江西、广东、湖南和广西省,面积分别占该区域的97.58%,89.65%,76.90%和73.08%;其次是浙江、福建、台湾和安徽省。湖北、江苏、四川、云南、贵州等省份也有中华穿山甲的零星分布。湖北东南部、江苏南部、浙江西南部和福建西北部等与江西接壤的区域也是中华穿山甲的重要潜在分布适宜区。明确中华穿山甲的潜在分布适宜区,可为该物种的种群保护和栖息地管理提供科技支撑。  相似文献   
83.
The spectra of absorption and fluorescence of Auramine O (OO) specimens in water solution and in cells, stained with Schiff-type auramine-SO2 reagents for DNA, were investigated. Using different specimens of the stain the accuracy and sensitivity of the cytofluorometric method were estimated by the next parameters: the value of the useful signal from the nucleus (no), the value of the production of no by the time constant of fading (tau), the value of proportion of the signal to the background (no/nphi) and, in addition, the value of the variation coefficient under the measurement of the rat liver tetraploid cells. The purity of the dye was shown to interfere largely with accuracy and sensitivity of the above method. Auramine 00 of the Reanal production appeared to have the best photometricl characteristics. For this, the maxima of the absorption spectrum in the 320--700 nm region in the solution and in the cell were 371 and 433 nm, and 375 and 436 nm, resp. The maximum of the fluorescence spectrum was found 521 nm and 526 nm, resp. for the solution (0.02%) and for the Auramine-SO2 treated cells. Moreover, an isomer of Auramine O (00) -- Auramine G can be used for detection and photometrical measurement of DNA and glycogen after the Feulgen and PAS reactions, resp.  相似文献   
84.
烟青虫核型多角体病毒的复制和染病后血淋巴蛋白的变化   总被引:4,自引:0,他引:4  
邓塔  蔡秀玉 《昆虫学报》1993,36(4):423-429
用烟青虫(Hiliothis assulta)核型多角体病毒感染5龄初烟青虫幼虫,以染病后24、48·,72、96/120小时分别测定了虫体血淋巴蛋白浓度的变化。幼虫染病后24小时血淋巴蛋白浓度要高于同期对照组,72小时后染病幼虫血淋巴蛋白浓度较对照急剧下降。在染病及对照血淋巴样品中电泳分析(PAGE)三种蛋白(普通蛋白、糖蛋白和脂蛋白)均可分别染出22条、3条和3条带。分析结果表明,在虫体正常生长代谢过程中发生变化的主要蛋白可能大多为糖脂复合蛋白,但病毒的侵染能抑制这些变化的产生。电镜观察染病毒后幼虫的中肠组织和气管上皮组织,发现中肠染病轻微,不形成多角体。气管上皮细胞感染情况表明其属于对NPV感染较为敏感的组织之一,并在虫体染病后的病毒二次感染上可能起着重要作用。  相似文献   
85.
Using absorption and fluorescent cytophotometry methods, glycogen contents were studied in hepatocytes located in liver lobules and in hepatocytes, which make the general population of these cells in normal and cirrhotic rat liver. In cirrhosis, the content of glycogen in hepatocytes located in lobules obviously rises in comparison with the norm, but to a lesser degree, than in hepatocytes making the general population of these cells in cirrhotic liver. The content of glycogen in hepatocytes, located in lobules of pathologically changed liver in bemithyl treated rats, did not differ from the norm. At the same time, the glycogen content in hepatocytes, representing the general population of these cells in cirrhotically altered bemithyl injected rat liver, remained higher than in the norm. The data obtained indicate that distinctions in particular cell microinvironment, obviously present in cirrhotic liver, render essential influence on hepatocyte functional activity.  相似文献   
86.
Study of influence of new antitumor preparations bifolar and chlofiden on rat liver protein biosynthesis in vivo and on sarcoma-45 in vitro was carried out using labeled precursor 3H-leucine. It was shown that the preparations inhibited protein synthesis in normal and malignant tissues. Mitotic cycle and its phases were investigated with 3H-tymedin. It was established that bifolar influenced all the phases of mitotic cycle and the sensitive phases of the mitosis itself, which are connected with the redistribution of genetic material.  相似文献   
87.
The complex cytological, microbiological and immunological examination of 90 female patients with nonspecific inflammatory diseases of the genital tracts and 30 clinically healthy women (the control group) was carried out. The examination revealed significant microbiocenosis changes in the lumen and the parietal area of the vagina, depending on the severity of the infectious process: a decrease in the level of lactobacilli, an increase in the content of opportunistic facultative anaerobic microorganism in the lumen and obligate anaerobic bacteria in the parietal area. Pronounced correlation between the content of opportunistic microorganisms and the levels of IgM and IgA, as well as secretory IgA and free secretory component in vaginal secretions in patients in patients with non-specific inflammatory diseases of the genital tracts has been revealed.  相似文献   
88.
We evaluated the impact of non-native rainbow trout Oncorhynchus mykiss on a population of endemic Cedarberg ghost frog Heleophryne depressa in the upper Krom River (Olifants-Doring River Catchment, Cape Fold Ecoregion). We compared H. depressa abundance (using kick-sampling and underwater video analysis) and environmental conditions between sites above and below a waterfall that marks the upper distribution limit of O. mykiss. Heleophryne depressa abundance was significantly greater above the waterfall than that below it, and, because there was no significant difference in measured environmental variables, O. mykiss presence is identified as the most likely explanation for the observed decrease in H. depressa abundance.  相似文献   
89.
The effects of social stress caused by experience of defeats in mice during 3 or 10 consecutive days of intermale confrontations on serotonergic brain activity (5-HT, 5-HIAA levels and 5-HIAA/5-HT ratio) in some brain regions of CBA/Lac (CBA) and C57BL/6J (C57) inbred mice have been studied. It was revealed the significant changes in 5-HT methabolism in the brain regions of defeated mice (losers) of CBA strain after 3 intermale confrontations. However, after 10 days of social stress these changes (excluded amygdala) turned to the control measures testifying to the adaptive mechanisms of serotonergic system in CBA losers. In C57 strain, the three-day social stress produced the mild changes in the brain serotonergic activity both quantitatively as well as qualitatively. Nevertheless, losers subjected to ten-day intermale confrontations had more expressed changes in 5-HT, 5-HIAA levels of 5-HIAA/5-HT ratios in the brain regions studied. It seems that long lasting social stress induced the development of disbalance of the brain serotonergic activity in C57 losers: it was shown the hyperactivity in the hypothalamus and hypoactivity in the amygdala and nucl. accumbens. Apparently, this cause leads to the development of the pronounced anxiety shown earlier in this mouse strain.  相似文献   
90.
The reaction was studied of male mice of CBA and C57BL/6J lines to zoosocial signals coming from another individual. "Partition" test was used, in which two males of one line were placed in a common cage divided into two sections by a transparent partition with holes; this partition divided the animals but allowed them to see and sniff each other. The number of approaches to partition, summary and average time of staying near it during one approach were recorded. Mice of both lines reacted to presence of unknown partner behind the partition by an increase of activity near the partition; in CBA mice all recorded parameters were greater than in C57BL/6J mice. A greater sensitivity is suggested of CBA animals to perception of pheromonal signals. "Partition" test may be used for estimation of mice reaction to zoosocial signals.  相似文献   
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