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闽西北棘胸蛙生态调查及人工试养观察 总被引:4,自引:0,他引:4
棘胸蛙(Rana spinosa)在贵州、湖北、江苏、浙江、安徽、湖南、福建、广东、广西、江西等省均有分布,数量也多。棘胸蛙体大肉鲜,有较高的食用和药用价值。布尔恩格尔(Boulenger)曾于1892年、1899年先后曾记载在湖北、浙江、福建发现有棘腹蛙,1920年他又改定为棘胸蛙。丁汉波(1944—1956)在研究福建的两栖动物时曾对棘胸蛙有过报道,但目前国内对棘胸蛙系统的生态等方面的研究尚未很好地开展。刘承钊等(1961)曾建议设法在池塘中试养,而国内至今未见人工养殖棘胸蛙的报道。 相似文献
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Paa bourreti的有效性及其在中国的新纪录 总被引:1,自引:1,他引:0
用线粒体12S和16S基因序列对双团棘胸蛙Paa yunnanensis的8个种群和越南的Paa bourreti进行分子系统发育分析,结果表明,双团棘胸蛙景东种群与Paa bourreti聚为一支,而其他7个种群聚为一支;以上两支问的遗传分化水平已经达到种级.此外,形态比较结果表明景东地区标本与双团棘胸蛙形态特征不同而与P.bourreti基本一致.因此,支持P.bourreti为有效种,双团棘胸蛙景东种群应为P.bourreti,为中国新纪录;推测其在云南南部其他区域也有分布.根据云南景东的标本,本文对P.bourreti进行了形态补充描述. 相似文献
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鄂西棘腹蛙的生活习性及其食性的初步研究 总被引:15,自引:0,他引:15
棘腹蛙为山区流溪型种类,广食性,成蛙以捕食昆虫等动物性食物为主,蝌蚪主要摄食藻类等植物食物。棘腹蛙有显著消灭为害森林的动物(昆虫),其有益系数为68.31%。 相似文献
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棘腹蛙(Rana boulengeri Günther)早期胚胎发育与分期的研究 总被引:3,自引:0,他引:3
本文研究了湘西地区棘腹蛙(R.boulengeriG.)的早期胚胎发育与分期.用人工诱导排卵、人工授精的方法获得受精卵,在控制水温为(23±0.5)℃下发育,棘腹蛙的胚胎发育从人工授精开始到蝌蚪的鳃盖完全闭合需要261h;以胚胎形态变化和主要生理特征的出现为基础,该蛙早期胚胎发育可分为25个时期.棘腹蛙发育过程中的形态特征和其它无尾两栖类相似,但在某些方面也呈现出与适应山地溪流环境有关的一些特点. 相似文献
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我们在棘腹蛙能流模型及人工繁殖技术研究中,对其营养成份及含肉率进行了初步研究。 材料 棘腹蛙幼娃和成蛙,均来自湘西的溪流中。 方法 1.将12只活蛙擦干称重后处死,除去皮肤与内脏,然后分成头、躯干、前肢和后肢等部分,并除去非肌肉质后称重,得各部分的肌肉含量。2.用索氏提取法测定脂肪含量,用微量凯氏定氮法测定蛋白质含量。3.用日立835—50型氨基酸分析仪测定肌肉蛋白质的各种氨基酸含量。4.用GR3500-B1微电脑热量计测定肌肉的能量含量。 相似文献
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Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis
It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis. 相似文献
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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera. 相似文献
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted. 相似文献
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肝癌中HBV和HCV基因和抗原的分布及意义 总被引:1,自引:0,他引:1
采用原位分子杂交方法检测HCV
RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV
RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV
RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV
X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV
C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细 相似文献
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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献