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大中型食肉动物肇事事件导致人类与野生动物关系恶化,给生物多样性保护工作带来巨大的挑战。若尔盖湿地是我国三大湿地之一,湿地、草原分布广泛,生物多样性丰富,畜牧业发达,但近年来狼(Canis lupus)捕杀牲畜的肇事事件时有发生。为了解若尔盖野生狼肇事件的空间分布以及牧民对人-狼冲突管理的看法,本研究于2022年对若尔盖县13个乡镇83个行政村进行走访调查。结果表明:(1)多数受访者(66.0%)认为在过去5年内,若尔盖县野生狼数量有所增加;(2)狼肇事事件具有明显的空间分异性,最严重的是包座乡。包座乡临近山区,该区域牧场面积广阔、牧民饲养牲畜数量多等原因导致该镇发生狼肇事事件较多;(3)对于狼肇事,绝大多数牧民(85.0%)更希望采取经济补偿或者驱赶措施,只有少数牧民(9.4%)希望采取捕杀的措施;(4)影响牧民对狼肇事管理措施的偏好因子中,受教育程度、年龄、民族以及被杀牲畜数量有显著影响。建议加强狼种群监测管理,采取措施减少狼捕杀牲畜,优化补偿机制,缓解当地牧民与狼之间的矛盾。本研究为当前若尔盖县野生动物保护和管理决策提供了依据,对其他地区大型食肉动物与当地居民冲突管理具有借鉴意义。 相似文献
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Nathan A. Jud Ari Iglesias Peter Wilf Maria A. Gandolfo 《American journal of botany》2018,105(5):927-942
Premise of the Study
The fossil record is critical for testing biogeographic hypotheses. Menispermaceae (moonseeds) are a widespread family with a rich fossil record and alternative hypotheses related to their origin and diversification. The family is well‐represented in Cenozoic deposits of the northern hemisphere, but the record in the southern hemisphere is sparse. Filling in the southern record of moonseeds will improve our ability to evaluate alternative biogeographic hypotheses.Methods
Fossils were collected from the Salamanca (early Paleocene, Danian) and the Huitrera (early Eocene, Ypresian) formations in Chubut Province, Argentina. We photographed them using light microscopy, epifluorescence, and scanning electron microscopy and compared the fossils with similar extant and fossil Menispermaceae using herbarium specimens and published literature.Key Results
We describe fossil leaves and endocarps attributed to Menispermaceae from Argentinean Patagonia. The leaves are identified to the family, and the endocarps are further identified to the tribe Cissampelideae. The Salamancan endocarp is assigned to the extant genus Stephania. These fossils significantly expand the known range of Menispermaceae in South America, and they include the oldest (ca. 64 Ma) unequivocal evidence of the family worldwide.Conclusions
Our findings highlight the importance of West Gondwana in the evolution of Menispermaceae during the Paleogene. Currently, the fossil record does not discern between a Laurasian or Gondwanan origin; however, it does demonstrate that Menispermaceae grew well outside the tropics by the early Paleocene. The endocarps’ affinity with Cissampelideae suggests that diversification of the family was well underway by the earliest Paleocene. 相似文献46.
This paper probes into the feasibility of increasing expression level of hFIX gene with endogenous intron 1 sequence.hFIX minigene was obtained with middle sequence truncated intron 1 inserted into the relative site of hFIX cDNA,and plasmid vector pKG5i‘IX,retroviral vector G1NaCi‘IX were constructed.These vectors were transduced into target cells of PA317,C2C12,primary rabbit skin fibroblasts (RSF) and primary human skin fibroblasts (HSF).The expression level of mixed colonies are PA317/pKG5i‘IX,151 ng/10^6 cells/24h;PA317/G1NaCi‘IX,308 ng/10^6 cells/24 h;C2C12/G1NaCi‘IX,186 ng/10^6 cells/24 h;RSF/G1NaCi‘IX,1929 ng/10^6 cells/24 h;HSF/G1NaCi‘IX,1646 ng/10^6 cells/24 h.These results indicated that hFIX minigene with intron l is able to increase the expression level to about 3 times of that of hFIX cDNA.Meanwhile,in order to study the application of hFIX minigene in the retroviral-mediated gene transfer system and refrain from intron splicing during viral production,a retroviral vector G1NaCi‘IXR with reversely inserted hFIX minigene expression cassette was constructed.The expression level of reverse constructor in PA317 cells was 390 ng/10^6 cells/24 h with 79% of bioactivity.PCR detection of HT/G1NaCi‘IXR cells infected with PA317/G1NaCi‘IXR supernatant confirmed the existence of intron 1 sequence.These results suggested that expression vector with forward-inserted intronl-carrying hFIX expression cassette can be used in directed gene transfer,but when using the retroviral-mediated gene transfer system,reversely-inserted intronl-carrying hFIX expression cassette should be considered. 相似文献
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从康氐木霉(Trichoderma k(?)ningii)白色变异株As 3.4001的粗酶制剂中,获得了纤维素酶系中的一组C_x酶(C_(x1) C_(x2) C_(x3) C_(x4))。分离步骤包括Sephadex G-75凝胶过滤,DEAESephadex A-50离子交换层析,ConA-Sepharose亲合层析,SE-Sephadex C-50离子交换层析及聚丙烯酰胺凝胶电泳。C_(x1)与C_(x2)的分子量不同而所带电荷相同,它们的分子量各自为44,500和34,000。C_(x2)—C_(x4)的分子量相同而所带电荷不同。纯化的C_(x1)—C_(x4)经聚丙烯酰胺凝胶电泳鉴定为单带。比较它们对羧甲基纤维素钠(CMC-Na)的糖化力及液化力表明在作用方式的随机性上C_(x2)>C_(x3)>C_(x1)>C_(x4)。 相似文献
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马铃薯糖转运蛋白基因的克隆及表达分析 总被引:1,自引:0,他引:1
植物SWEET基因家族是一类糖转运蛋白,在植物的生理活动和生长发育过程中发挥着重要功能。为了解马铃薯SWEET基因的相关信息,探究其在马铃薯不同组织以及在生物胁迫与非生物胁迫下的表达特性。该研究采用同源克隆技术从马铃薯‘青薯9号’中克隆了StSWEET5基因(GenBank登录号为MN295671),其CDS序列长度为717 bp,编码238个氨基酸。系统进化树分析结果表明,StSWEET5与番茄的氨基酸序列相似性最高(97.06%)。qRT-PCR分析表明:StSWEET5基因在马铃薯各组织(根、茎、叶、花、块茎、匍匐茎)中均有表达,且在花中的表达显著高于其他组织;糖胁迫下,StSWEET5基因在根、茎、叶中均有表达,尤其在根中的表达差异最为显著(P0.05)。在晚疫病菌(Phytophthora infestans)诱导后36 h时,表达量达到最高,随后急剧下调。推测StSWEET5基因参与了马铃薯糖胁迫以及响应了晚疫病诱导的过程。 相似文献
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Background
Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India 相似文献50.
报道了采自内蒙古呼伦贝尔市的中国疣柄牛肝菌属1个新记录种,即假褐疣柄牛肝菌Leccinum pseudoscabrum(Kallenb.)utara.。主要特征为菌肉伤后变红到紫褐色,再到黑褐色,基部菌丝体手触后呈紫褐色;具泡状菌丝,呈栅栏状。比较和讨论了该种与相近种在伤后不同的变色反应及菌丝形态。研究标本存放于吉林农业大学菌物标本馆(HMJAU)。 相似文献