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991.
应用逆转录-聚合酶链式反应(RT-PCR)技术从吸血后24 h埃及伊蚊海口株总RNA中扩增出了后期胰蛋白酶编码区cDNA序列。采用自动DNA分析仪进行序列分析,并与已知埃及伊蚊美国株后期胰蛋白酶基因及推导的氨基酸序列进行了同源性比较。结果表明:埃及伊蚊海口株后期胰蛋白酶基因序列与美国株同源性达98%,有11个碱基发生变异;氨基酸同源性达99%,仅有3个氨基酸发生变异,但与催化位点密切相关的氨基酸及N末端氨基酸序列完全一致。以上结果显示,埃及伊蚊胰蛋白酶不同地理株间存在微小的差异。 相似文献
992.
Seasonal changes of thermogenic capacity in Melano-bellied oriental voles (Eothenomys melanogaster)☆ 下载免费PDF全文
Seasonal changes of thermogenic capacity in Melano-bellied oriental voles (Eothenomysmelanogaster) were studied by measurements of body mass, basal metabolic rate (BMR), non-shivering thermogenesis (NST), thermogenic properties of brown adipose tissue (BAT), relative weight of liver mass, mitochondrial protein (MP) content, and activities of mitochondrial cytochrome C oxidase (COX) in autumn (October), winter (December), spring (April) and summer (July), respectively.
Results showed that: (1) Body mass of E.melanogaster was the highest in autumn, and the lowest in summer. The seasonal change in body mass was subject not only by environment temperature but also to other factors such as reproduction, feeding habit and climate in the habitat. Reproductive periods of E.melanogaster were in early spring (February–March) and late autumn (September–October), and therefore, the body mass was higher in spring and autumn. In addition, E.melanogaster feeds on leaves and stems of plants in spring and summer, whereas mainly on fruits in autumn and winter as they contain more energy. The difference in the feeding habit could result in higher body mass in the late half of the year, but lower body mass in winter. The lower body mass in winter provides E.melanogaster with an advantage in motility. (2) The BMR and NST of E.melanogaster was higher in winter than in other seasons, which suggests that the regulating thermogenic capacity is an important adaptive strategy for E.melanogaster. However, there was no difference in relative oxygen consumption (NST–BMR/BMR), suggesting that the regulative capacity of BMR is approximately equal to NST in E.melanogaster. This is different from some small mammal species in north China, which have higher regulative capacity in NST than E.melanogaster. Melano-bellied oriental voles live in mountainous area with subtropical zone monsoon climate and abundant food resource, and therefore have lower regulative capacity in NST, which can reduce an absolute request for energy. The low regulative capacity in NST can also help E.melanogaster to maintain energy balance and stable body temperature. (3) The relative mass of BAT in winter was significantly higher than that in summer. Different seasons significantly affected the MP content of BAT. The MP content of BAT was in the following order: winter > fall > spring > summer. The trend as following was observed for the mitochondrial COX activity of BAT: winter > spring > fall > summer. In experimental conditions, the thermogenic rate of many small mammal species increased under cold acclimation. Short photoperiod alone could also induce E.melanogaster to increase NST and mitochondrial COX activity of BAT. Therefore, ambient temperature and photoperiod are important environmental cues to induce seasonal changes in thermogenic capacity in E.melanogaster. (4) The relative mass of liver in summer was higher than that in other seasons, but no seasonal changes were found among other seasons. The MP contents of liver showed highest level in winter and lowest in spring and summer. Significant seasonal changes were also observed in the mitochondrial COX activity of liver. It increased significantly in winter, but not in other seasons. This indicates that liver participate in adjustment of thermogenesis. These data indicate that both increasing whole-animal thermogenesis rate and thermogenic capacity at the cells of BAT and liver play an important role in the adaption of E.melanogaster to seasonal changes, and they are also closely correlated with the habitat condition and their life habit. 相似文献
Results showed that: (1) Body mass of E.melanogaster was the highest in autumn, and the lowest in summer. The seasonal change in body mass was subject not only by environment temperature but also to other factors such as reproduction, feeding habit and climate in the habitat. Reproductive periods of E.melanogaster were in early spring (February–March) and late autumn (September–October), and therefore, the body mass was higher in spring and autumn. In addition, E.melanogaster feeds on leaves and stems of plants in spring and summer, whereas mainly on fruits in autumn and winter as they contain more energy. The difference in the feeding habit could result in higher body mass in the late half of the year, but lower body mass in winter. The lower body mass in winter provides E.melanogaster with an advantage in motility. (2) The BMR and NST of E.melanogaster was higher in winter than in other seasons, which suggests that the regulating thermogenic capacity is an important adaptive strategy for E.melanogaster. However, there was no difference in relative oxygen consumption (NST–BMR/BMR), suggesting that the regulative capacity of BMR is approximately equal to NST in E.melanogaster. This is different from some small mammal species in north China, which have higher regulative capacity in NST than E.melanogaster. Melano-bellied oriental voles live in mountainous area with subtropical zone monsoon climate and abundant food resource, and therefore have lower regulative capacity in NST, which can reduce an absolute request for energy. The low regulative capacity in NST can also help E.melanogaster to maintain energy balance and stable body temperature. (3) The relative mass of BAT in winter was significantly higher than that in summer. Different seasons significantly affected the MP content of BAT. The MP content of BAT was in the following order: winter > fall > spring > summer. The trend as following was observed for the mitochondrial COX activity of BAT: winter > spring > fall > summer. In experimental conditions, the thermogenic rate of many small mammal species increased under cold acclimation. Short photoperiod alone could also induce E.melanogaster to increase NST and mitochondrial COX activity of BAT. Therefore, ambient temperature and photoperiod are important environmental cues to induce seasonal changes in thermogenic capacity in E.melanogaster. (4) The relative mass of liver in summer was higher than that in other seasons, but no seasonal changes were found among other seasons. The MP contents of liver showed highest level in winter and lowest in spring and summer. Significant seasonal changes were also observed in the mitochondrial COX activity of liver. It increased significantly in winter, but not in other seasons. This indicates that liver participate in adjustment of thermogenesis. These data indicate that both increasing whole-animal thermogenesis rate and thermogenic capacity at the cells of BAT and liver play an important role in the adaption of E.melanogaster to seasonal changes, and they are also closely correlated with the habitat condition and their life habit. 相似文献
993.
Corn stover (CS) hydrolysate was used as the fermentation feedstock of Trichosporon cutaneum CX1 for production of microbial lipid as the potential raw material of biodiesel. Two major technical barriers of the lipid fermentation were investigated: one was the strong inhibition of lignocellulose degradation compounds generated in the CS pretreatment; the other was the low carbon-to-nitrogen molar ratio (C/N ratio) of the CS hydrolysate. The newly established biodetoxification method was applied to remove the inhibitors in the pretreated CS. The enhancement of the pretreatment severity and the biodetoxification intensity on the lipid fermentation was investigated. The results show that the biodetoxification not only efficiently removed the inhibitor substances, but also led to the reduction of nitrogen content and the increase of C/N ratio. The cell lipid content of T. cutaneum CX1 using the biodetoxified CS hydrolysate reached 23.5%, which was doubled than that using the non-detoxified value. 相似文献
994.
995.
Groves K Bao B Zhang J Handy E Kennedy P Cuneo G Supuran CT Yared W Peterson JD Rajopadhye M 《Bioorganic & medicinal chemistry letters》2012,22(1):653-657
A series of human carbonic anhydrase (hCA) IX inhibitors conjugated to various near-infrared fluorescent dyes was synthesized with the aim of imaging hypoxia-induced hCA IX expression in tumor cells in vitro, ex vivo and in vivo. The resulting compounds were profiled for inhibition of transmembrane hCA IX showing a range of potencies from 7.5 to 116 nM and up to 50-fold selectivity over the cytosolic form hCA II. Some of the compounds also showed inhibition selectivity for other transmembrane forms hCA XII and XIV as well. Compounds incubated in vitro with HeLa cells cultured under normoxic and hypoxic conditions detected upregulation of hCA IX under hypoxia by fluorescence microscopy. A pilot in vivo study in HT-29 tumor bearing mice showed significant accumulation of a fluorescent acetazolamide derivative in tumor tissue with little accumulation in other tissues. Approximately 10% of injected dose was non-invasively quantified in tumors by fluorescence molecular tomography (FMT), demonstrating the promise of these new compounds for quantitative imaging of hCA IX upregulation in live animals. 相似文献
996.
Biosynthesis of bacteriocins in lactic acid bacteria 总被引:52,自引:0,他引:52
997.
Xiao‐Guang Qi Bao‐Guo Li Paul A. Garber Weihong Ji Kunio Watanabe 《American journal of primatology》2009,71(8):670-679
Among primates that form multilevel societies, understanding factors and mechanisms associated with the movement of individuals between groups, clans, and one‐male social units offers important insight into primate reproductive and social strategies. In this research we present data based on an 8‐year field study of a multilevel troop of Sichuan snub‐nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains of China. Our study troop contained 78–126 individuals, and was usually organized into 6–8 one‐male units (OMU). The majority of OMUs were composed of networks of unrelated females and their offspring. We found that 59.7% (43/72) of subadult and adult females in our study troop transferred between OMUs (n=66) or disappeared (n=7) from the troop. In the majority of cases, two or more females transferred together into new OMUs or troops. In R. roxellana, new OMUs formed in several ways. During 2001–2008, 16 adult males appeared in the study troop. Over this period, we observed 13 different males who became harem leaders either by taking over an existing harem or by attracting females from other OMUs into their harem. We also observed four OMUs from a neighboring troop to successfully immigrate into the study troop. The number of individuals in these newly immigrated OMUs was significantly smaller than that number of individuals in resident OMUs. During harem formation, fighting between adult males was rarely observed, and female mate choice appeared to play a crucial role in harem male recruitment and replacement. These results suggest that golden snub‐nosed monkeys are organized in a nonmatrilineal social system. Female mate choice and possibly incest avoidance appear to play important roles in female transfer, male tenure, and OMU stability. Am. J. Primatol. 71:670–679, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
998.
Comparative transcriptome combined with morpho‐physiological analyses revealed key factors for differential cadmium accumulation in two contrasting sweet sorghum genotypes 下载免费PDF全文
999.
水温变化对绥芬河滩头雅罗鱼产卵的影响 总被引:4,自引:0,他引:4
The Dace ( Leucisus brandti Dybowski) was a migration fish in Suifen river. The Dace can spawn at the water temperatures from 7℃ to 25℃. Changing of water temperature is the leading factor cause the spawning population to ovulate. However, high or low current water temperature had no obvious effectuation on ovulating behavior of Dace. The ovulation of the Dace often occurred in the evening or next morning after the water temperature rapidly in creased. The fish spawning often occurred as the water temperature decreased at first, after a period of steady low water temperature, then increased. A massive ovulating action began at the time. If the rising of water temperature happens only after a period of steady level without any decreasing of the water temperature, the change can not stimulate ovulation of the Daces. Usually, every large scale ovulate can sustain for 1 or 2 days. The peak time of ovulation often appears in 48 hours after the water temperature increases. Once the spawning population began to ovulate, their actions will be very intense, so that even catching action of human on them can not prevent the ovulation. The test of artificial induced ovulation showed that only when variation of water temperature were more than 10℃ ( increased degree+decreased degree), the Dace would ovulate. The Dace began to ovulate in 12~36 hours after the water temperature's change. The efficient time was shorter and the ovulation rate was higher the variation of water temperature were greater. At the range from 8℃ to 24℃, as high or low water temperature had no effect on the efficient time stimulating ovulate, the Dace can not ovulate out of the temperature range. 相似文献
1000.
Deng S Zhang BJ Wang CY Tian Y Yao JH An L Huang SS Peng JY Liu KX Ma XC 《Bioorganic & medicinal chemistry letters》2012,22(4):1615-1618
A series of analogues of deoxyandrographolide (1) transformed by Cunninghamella blakesleana AS 3.2004 were isolated and identified by spectral methods including 2D NMR. Among them, 3-oxo-17,19-dihydroxy-7,13-ent-labdadien-15,16-olide (9), 3-oxo-19-hydroxy-1,13-ent-labdadien-15,16-olide (16), 3-oxo-1β-hydroxy-14-deoxy-andrographolide (17) and 3-oxo-2β-hydroxy-14-deoxyandrographolide (18) are new compounds. And their structure-activity relationships (SAR) of inhibitory activity on LPS-induced NO production in RAW 264.7 macrophage cells were also discussed. 相似文献