共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
佛洞地遗址位于云南省临沧市耿马傣族佤族自治县勐简乡勐简村大军赛村民小组燕子洞,坐落于一处东南开口的二叠纪灰岩穿洞,南临南汀河。2016~2017年,临沧市文物管理所在公路考古调勘期间发现该遗址;为进一步认识滇西地区旧石器时代晚期文化,2017~2018年对该遗址开展考古发掘工作。发掘区域位于洞内第四台面到第五台面间,共发掘20 m2,出土了包括石制品、动植物化石等在内的大量遗物。初步地层年代学分析显示,遗址时代为距今18400~14000年,共包含3期连续文化,文化遗物以石制品为主,总数达到9735件。佛洞地遗址作为一处热带-亚热带生境下的史前遗址,为我们构建旧石器时代晚期滇西地区文化序列、探讨特定自然生态背景下史前人类的文化适应提供了重要参考。 相似文献
3.
老龙洞史前遗址初步研究 总被引:1,自引:1,他引:0
本文记述了老龙洞史前遗址研究初步成果.在对石、骨、角制品的一般性质论述基础上,指出这一组合具有自身的一些特点,并有着文化上的广泛联系;依遗物和哺乳动物化石对其年代也作了初步讨论。初步研究结果表明,它是中国西南地区,特别是云南近年来发现的一处重要的包括旧石器时代晚期文化层在内的史前洞穴遗址,为研究中国南方旧石器时代晚期文化类型的多样性提供了一个重要的地点和一批有意义的文化遗物。 相似文献
4.
本文的主要目的是了解华南地区史前时期人类在行为活动上的历时性变化,希望在此基础上认识该地区史前人类文化行为模式和生业方式变迁问题。应用骨骼生物力学方法,对顶蛳山遗址、鲤鱼墩遗址、冲塘遗址、江边遗址及何村遗址古人类肢骨的相关骨骼生物力学特征进行了比较,并在更广泛的时空范围内和生业方式下进行了更多人群的对比。研究结果表明,华南地区史前时期在距今8000-4000年的时期内,不同考古学文化人群在活动方式上较为相似。虽然多数华南史前时期人群之间在骨骼的抗压和抗拉伸力以及抗扭转力方面存在显著性差异,但他们都表现出较高的活动性,均未显示出低水平行为活动的现象。这些人群在诸多骨骼生物力学特征上与已知的狩猎—采集型人群的最为相似,与农业定居型人群的差异显著。本文认为上述华南史前时期人群在行为活动上更接近狩猎-采集型。 相似文献
5.
6.
贵州省普定县穿洞出土的骨器是穿洞文化的重要标志。1979年首次试掘出土的骨器基本为磨制者, 类型主要有骨锥、骨铲、骨叉、骨棒及骨针等,多采用较厚的动物骨骼的碎片为原料加工而成。一次性出土数量如此多骨器的遗址在我国非常少见, 为研究中国旧石器时代晚期文化的多样性提供了一个重要地点和一批有意义的文化遗物, 并对研究我国旧石器时代骨器提供了丰富的材料, 增加了我们对骨器工具的制造工艺及用途的了解。 相似文献
7.
8.
1923年,法国古生物学家德日进、桑志华在宁夏水洞沟发现了旧石器文化遗址,通过发掘,出土了大量旧石器和动物化石,水洞沟因此而成为我国最早发现旧石器时代的古人类文化遗址,被誉为“中国史前考古的发祥地”。1988年,水洞沟遗址被国务院公布为“全国重点文物保护单位”。 相似文献
9.
昆明大板桥史前洞穴遗址试掘报告 总被引:2,自引:2,他引:0
本文记述了新发现的昆明大板桥史前洞穴遗址,出土的文化遗存较丰富,包括晚期智人牙齿、动、植物化石、用火遗迹和数以百计的石制品及少量的骨制品。其时代主要为早全新世,文化层下部可能到晚更新世晚期。石制品均甚细小,且以砸击法为主要打片方法,系我国南方首次发现。这样的组合,也是具有我国北方旧石器文化特色的史前文化在云南的首次发现。因此,它是一个具有特殊意义的史前人类洞穴遗址。 相似文献
10.
11.
12.
13.
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
14.
15.
16.
17.
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
18.
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
19.
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
20.
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