共查询到20条相似文献,搜索用时 15 毫秒
1.
Jiapeng Qu Ming Liu Min Yang Yanming Zhang Weihong Ji 《European Journal of Wildlife Research》2012,58(1):269-277
The reproduction of the plateau pika (Ochotona curzoniae) was investigated in Guoluo District at an elevation of 4,000 m on the Qinghai–Tibetan plateau, China, from April 2007 to
August 2008. Reproduction was seasonal, and the breeding season lasted from April to late June/early July. Adults produced
two litters in each year, and the mean litter size, estimated by counting the number of embryos in utero, was 3.3 ± 0.1 (n = 52) in 2007 and 3.2 ± 0.1 (n = 66) in 2008. The timing of reproduction showed high inter-annual variation; lower precipitation and the concomitant delay
in spring vegetation phenology may have retarded the onset of the breeding season in 2007 compared with 2008. The most frequent
litter sizes were 3 and 4, which together comprised 71.2% and 83.3% of litters in May and June of 2007 and 2008, respectively.
Compared with previous studies, reproduction was highly variable between geographic areas. Pikas produced between one and
five litters per year in different regions of the plateau over different breeding seasons. This geographic and inter-annual
variation appeared to be associated with the duration of plant growth at each site, suggesting that plateau pikas adjust the
length of their breeding season to match the period when sufficient energy is available to support the high energy demands
of reproduction. 相似文献
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The bird remains from Valbro belong only to three taxa, Paraortyx lorteti, Archaeotrogon venustus, and A. zitteli. This association makes it possible to ascribe to this locality an early Oligocene age, reference-levels MP 22 or MP 23, which is in agreement with the age given by the mammals. 相似文献
4.
Sinularia leptoclados (Ehrenberg, 1834) is re-described. Sinularia leptoclados var. gonatodes Kolonko, 1926 is synonymized with Sinularia maxima Verseveldt, 1977. Two new species of Sinularia with digitiform lobules, leptoclados-type surface clubs and unbranched interior spindles, are described. An updated maximum likelihood tree of Sinularia species with leptoclados-type clubs (clade 5C) based on two mitochondrial genes (mtMutS, COI) and a nuclear gene (28S rDNA) is presented. 相似文献
5.
《中国应用生理学杂志》1990,(4)
Ba ZhengfengB ian RulianCai PingCai YingnianCao YinxiangChell GengxinChen rlaozh:-Chenl一JuaiqingChen JiqiangChen JiqiuChen Ji、lzer,gChen JialiangChen JiaPei巴正丰卞如赚蔡平蔡英年曹银祥陈庚新陈颧珠陈槐卿陈季强陈吉球陈继生陈佳亮陈家佩Chen JieCI,en JunhuiChen LianbiChcn MingzlzeChen PeixiChen PinfangCI又en RendunChen ShiliangChen ShuzhiChen WanyingChen XiushengChe若1 YingmaoChen YizhangChel飞y、zhuaiChen ZhcnxingChen ZhengyuChen Zht!huaCheng HaiyunCheng JiataiChi Kuixia… 相似文献
6.
《中国应用生理学杂志》1993,(4)
Ai Hongbing艾洪滨Ai Mingxian艾明仙An Gang安刚Bai Zhiquan柏志全Bao Yunhua鲍云华Bi Yutian毕玉田Cai Yan蔡淡Cai Yingnian蔡英年Cai Yingyun蔡映云Cao Hong列曹宏宇Cao Yinxiang一曹银祥Cao zhaofeng曹兆丰Cao zhenwu曹祯吾Chang Zhijie常志杰cho Gang陈刚Chen Jisheng陈继生Chen Jiajin陈家津Chen JiaPei陈家佩Chen Jianguo陈建国Chen Jiankang陈健康Chen Jie陈杰Chen Junpao陈俊抛Chen Limin陈丽敏Chen Long陈龙Chen Peixi陈培熹Chen Rendun陈仁博Chen Rongsan陈荣三Chen Shen郎i陈生弟Chen Xiaoling陈晓玲Che… 相似文献
7.
Oxidative stimulation induced by hydrogen peroxide (H2O2) on human lens epithelial cells (HLECs) was performed to observe the effects on cell viability and caveolin expression, and
cholesterol depletion in HLECs caused by methyl-β-cyclodextrin (MβCD) was also studied. SRA01/04 HLECs were exposed to H2O2 or MβDC of various concentrations and durations. We used a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)
assay to measure the effect of H2O2 on the viability of SRA01/04 HLECs. The distributions of caveolins after oxidative stimulation were probed by fluorescence
microscopy and laser scanning confocal microscopy. Immunoblotting was performed to analyze alterations of caveolins expression.
We observed that the viability of SRA01/04 HLECs under 0.1 mM H2O2 for 10 min or longer was significantly reduced (*p < 0.05, F = 11.63). Laser scanning microscopy showed immunofluorescent caveolins in SRA01/04 HLECs under 0.1 mM H2O2 for 10 min or longer; caveolins were largely confined to intracellular domains. Western blots showing both membrane and total
caveolin protein (22 kDa) levels in SRA01/04 HLECs treated with 0.1, 0.2, 0.5, or 1.0 mM H2O2 for 30 min were significantly reduced, compared with the untreated (*p < 0.05, F = 6.149, or *p < 0.05, F = 14.489, respectively). In addition, the membrane and total caveolin protein level after being treated with 0.1 mM H2O2 (*p < 0.05, F = 6.843, or *p < 0.05, F = 7.944, respectively) for different durations also down regulated. Fluorescence microscopy also showed that phosphorylated
caveolin-1 was distributed near the focal adhesions of the cells. This study concludes that the responses of HLECs to oxidative
stress may include down regulation of caveolin and phosphorylation of caveolin-1 on tyrosine 14 and that MβCD also down regulates
caveolin while depleting cholesterol in HLECs.
Published in Russian in Molekulyarnaya Biologiya, 2007, Vol. 41, No. 6, pp. 994–1001.
The article was submitted by the authors in English. 相似文献
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本文报道一例t(3; 22) (p21; q13)平衡
相互易位的家系。先证者,男性,一岁半,淋巴
细胞及皮肤成纤维细胞G带分析结果:核型均
为46, XY, t(3; 22)(p21;q13)或46, XY,t(3;
22)(3gter” 3p21::22813” 22gter;2 2 pter”
22gl3::3p21” 3 pter );先证者母亲(图1)与
外祖母核型均为46, XX, t(3; 22)(p21; q13)
或46, XX, t(3; 22)(3gter、3p21::22813一
22gter; 22pter~ 22813::3p21一3pter)。经银
染与G带复合显示技术,先证者及母亲的22der
可见清晰的AgNOR区。先证者的父亲与舅父
G带分析核型正常。在此情况下,有生育正常
婴儿的可能,但必须作产前诊断。 相似文献
10.
Caragana is endemic to temperate Asia, with most species distributed on the Qinghai–Tibetan Plateau (QTP) and in Northwestern China. Consequently its biogeography should be hypothesized to have been affected by QTP uplift. To examine the biogeography of Caragana in relation to QTP uplift and consequent interior aridification, we conducted molecular dating analyses based on three genes (ITS, cpDNA trnS-trnG and rbcL). Results from relaxed Bayesian BEAST, relaxed Bayesian Multidivtime, and PL (penalized likelihood) indicate that QTP uplift, especially the onset of Himalayan motion at 21–17 Ma, triggered the origin of Caragana (with estimated ages 16–14 Ma). The subsequent QTP rapid uplift at 8 Ma is inferred to have driven the evolution and diversification of the three major clades of Caragana: section Caragana (northern China and the Junggar–Altai–Sayan region), section Frutescentes (Central Asia), and sections Bracteolatae and Jubatae, centered in the QTP. A rapid and active speciation process occurring in the QTP intense uplift at 3.4–1.8 Ma, is indicated by the chronogram. 相似文献
11.
P Milonas C Gogou A Papadopoulou S Fountas V Liakos N T Papadopoulos 《Neotropical Entomology》2016,45(3):240-251
12.
Searching for materials and technologies of efficient CO2 capture is of the utmost importance to reduce the CO2 impact on the environment. Therefore, the (AlN)n clusters (n = 3–5) are researched using density functional theoretical calculations. The results of the optimization show that the most stable structures of (AlN)n clusters all display planar configurations at B3LYP and G3B3 methods, which are consistent with the reported results. For these planar clusters, we further systematically studied their interactions with carbon dioxide molecules to understand their adsorption behavior at the B3LYP/6–311+G(d,p) level, including geometric optimization, binding energy, bond index, and electrostatic. We found that the planar structures of (AlN)n (n = 3–5) can capture 3–5 CO2 molecules. The result indicates that (AlN)n (n = 3–5) clusters binding with CO2 is an exothermic process (the capture of every CO2 molecule on (AlN)n clusters releases at least 30 kcal mol-1 in relative free energy values). These analysis results are expected to further motivate the applications of clusters to be efficient CO2 capture materials. 相似文献
13.
Gouw等于1973年首次报道了t(6;18)(p22;q12)病例。同年,Nakagme等也发现了t(6;18)(q27;q11)核型。迄今国外共发现至少9种关于t(6;18)核型。而国内尚未见公开报道。 作者从遗传咨询门诊病人中,检出一例至今未见报道过的t(6;18)del(18)综合征患者。现简要报告如下。 相似文献
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TwoRareCasesofChromosomeTranslocationt(1;3)andt(9;19)WeiRongshangZhangHaiduanWangAiqinHeChunna(LaboratoryofGenetics,NanjingHospitaloftheAirForceofPLANanjing210002)例1男,28岁,结婚2年余,妻27岁,妊娠3次,第1胎孕5个月胎死宫内,第2胎7 月早产后夭折,第3胎5个 相似文献
16.
Debraj Kole Subinoy Mondal Apurba Ratan Ghosh 《Proceedings of the Zoological Society》2018,71(2):178-185
Effects of two different concentrations of arsenic (8.88 mg/l and 17.76 mg/l i.e., 25 and 50% of LC50 value) respectively and chromium (15.45 mg/l and 30.90 mg/l i.e., 25 and 50% of LC50 value respectively) were evaluated on digestive enzymes of Anabas testudineus for a period of 30 days under laboratory condition. Here As1 and As2, and Cr1 and Cr2 were referred to indicate the 25 and 50% of LC50 value of arsenic and chromium respectively. The result of different enzymes in different tissues was as follows: amylase and lipase activities showed highest in stomach, i.e., 466.81 and 283.33% respectively at 50% concentration of chromium; but moderate (272.78% at 25% of Cr and 264.65% at 50% of As) followed by lowest 219.07% at 25% As concentration. Protease activity at different concentrations of metals was in the order of As2 > As1 > Cr2 > Cr1. Protease activity showed highest in As2 or 50% concentration of As (397.92%) and lowest in 25% of Cr (316.39%). Lipase activity showed highest increment in intestine under As2 (409.23%) and lowest activity in Cr1 (137.84%). In intestine, the protease activity increased at As1 (288.99%) and the highest at As2 i.e., 367.39% compared to other concentrations. The significant changes (p > 0.05) in the enzyme activities in the different tissues like stomach and intestine in regard to different doses were investigated along with regression lines. So, it can be inferred that digestive enzyme activities of A. testudineus may be considered as the potential biomarkers for arsenic and chromium contamination in aquatic systems. 相似文献
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New and known homo- and heterodinuclear RuII and OsII complexes with 4,4-bipyridine (4,4-bpy), pyrazine, and 4-pyCH=CHpy-4 as bridging ligands (LL) of the type [Cl(bpy)2M(LL)MCl(bpy)2]X2 (bpy=2,2-bipyridine; X=PF6 or BF4) have been studied in their capacity to exchange electrons with a reduced active site of glucose oxidase (GO) from Aspergillus niger. Cyclic voltammograms (CVs) of the dimers in the aqueous buffered solution, when compared with CVs of the parent monomeric species [MCl(LL)(bpy)2]BF4 and [MCl2(bpy)2] which could be generated at pH7, if the dimers undergo monomerization, indicate that the dimers are the dominating species under such conditions. All electrochemically oxidized dinuclear complexes studied show high rates of oxidation of GO reduced by d-glucose and the corresponding observed second-order rate constants are in the range (5–64)×105 M–1 s–1 at 25 °C. However, these values are lower than that for the mononuclear complex [OsCl(4,4-bpy)(bpy)2]BF4 (1.1×107 M–1 s–1), suggesting that potentially two-electron dimeric mediators have no advantage compared with corresponding monomeric complexes of RuII and OsII. The structure of [OsCl(4,4-bpy)(bpy)2]BF4 was confirmed by X-ray crystallography. The monodentate 4,4-bpy ligand is coordinated cis to the chloride. Its higher reactivity toward reduced GO is accounted for in terms of the antenna effect of the monodentate 4,4-bpy ligand. The antenna length equals 9.2 Å and matches the depth of the enzyme active site pocket of ca. 10 Å. The mechanism of the antenna effect is discussed 相似文献
19.
《天然产物研究与开发》2004,(5)
天津尖峰天然产物公司是一家专业从事天然植物提取、研究、开发、生产、销售的专业综合公司。目前是国内最大的葡萄籽提取物生产厂家 ,同时推出红景天提取物。红景天 (Rhodiola)系景天科红景天属植物 ,藏语称“苏罗玛布”。系草本或亚灌木植物 ,因其含花色素 ,根及根茎呈红色 ,浸液亦呈红色 ,又系景天科植物 ,故名红景天。红景天属植物大部分生长在海拔 35 0 0~ 5 0 0 0米的山地、冰川、山梁草地或山谷岩石上 ,广泛分布于中亚、东亚西伯利亚及北美地区 ,我国的红景天资源主要分布在东北、西北、华北及西南的一些地区。红景天产地用其作滋… 相似文献
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《中国应用生理学杂志》1992,(4)
勇羽陈陈 Ao Zhaohui Bai Yan Bian Shiehun Bu Fengrong Bu Guanghui Bu Haizhi Cai Qiqiang Cai Yingnian Cao Jimin Chai Huixia Chang Zhijie Chen Chuanrong Chen Guozhi Chen HuaweiChen JishengChen Jiajin Chen JunminChen ShaoyangChen ShuziChen SongsenChen WeiChen XiaoliangChen YongChen YuChen YuanluChen ZhixiongChen ZirongCheng LiyanCheng TongCheng YongChu YideCui RongqingCui WenyuDai BosongDeng XixianDing AishiDing GuifengDing HuDing JiangzhouDing ShifaDing TingkaiDing… 相似文献