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1.
在河北省阳原县大黑沟中更新世和岑家湾附近石沟早更新世地层中分别发现了犀牛的下颌骨和股骨化石。其下颌联合部窄长、无下门齿、牙齿釉质层平滑而无褶皱、牙齿表面无垩质充填,股骨较披毛犀的长,故将其归入梅氏犀(Stephanorhinus kirchbergensis)。泥河湾盆地的化石是我国早期梅氏犀化石中材料最可靠,地点层位最明确的记录。山神庙咀和大黑沟出土的板齿犀牙齿及前脚骨化石,是泥河湾盆地发现的最好材料,尤其是大黑沟出土的板齿犀牙齿化石,是迄今在泥河湾盆地首次发现的完整材料;依据冠面结构和测量数据,该批材料可归入裴氏板齿犀(Elasmotherium peii);裴氏板齿犀特征鲜明,是有效名称,我国早更新世的板齿犀均应归入该种。我国第四纪的板齿犀与高加索板齿犀之间存在显著差异,表现在釉质层厚度较大但褶皱不够强烈、下颊齿的下后尖发育、颊齿冠面的前后径多数大于颊舌径、M3比M2小、M3后附尖欠发育,后脊与外脊已完全融合、上颊齿的齿脊更厚。此外,我国的板齿犀与西伯利亚板齿犀也有差异,后者的牙齿齿冠更高、无齿根、釉质层薄且褶皱强烈、上颊齿无后窝。最新地层研究表明,我国含板齿犀属的地层时代不晚于早更新世,且集中出现于下更新统。在晚新生代期间,犀牛在泥河湾盆地十分常见,先后出现过如下属种:大唇犀(Chilotherium sp.)(上新世)、裴氏板齿犀(Elasmotherium peii)(早更新世)、泥河湾披毛犀(Coelodonta nihowanensis)(早更新世)、梅氏犀Stephanorhinus kirchbergensis(早-中更新世)和真披毛犀(Coelodonta antiquitatis)(中-晚更新世)。  相似文献   

2.
泥河湾盆地是中国北方第四纪地层发育最为齐全的地区之一,多处哺乳动物化石产地及旧石器遗址中均有披毛犀化石产出(卫奇,1997),但报道产出的化石多数只是骨体碎片或零星的牙齿。1965年夏天,中国科学院古脊椎动物与古人类研究所前太原工作站王择义、王向前和武文杰在泥河湾盆地河北省阳原县东城乡虎头梁一带进行旧石器调查时,从褐黄色含细砾砂质粘土层中采集到一些披毛犀化石,产出地点位于虎头梁旧石器遗址NE55°方向350m处,地层层位位于旧石器产出层位之下的泥河湾组上部,时代为早更新世末期。这些技毛犀化石是该…  相似文献   

3.
泥河湾盆地最初以其广泛分布的含化石河湖相地层而受关注,并以其丰富的哺乳动物化石而著称于世,而今,泥河湾盆地已成为世界著名旧石器考古重地和研究第四纪地质古生物的重要场所。狭义泥河湾动物群(或下沙沟动物群)是我国北方早更新世的标准动物群,其古地磁年龄是2.2-1.7 MaBP。随着地层古生物工作的深入开展,盆地内也发现了若干中-晚更新世化石点;丁家堡水库全新统中发现的象颊齿,之前被鉴定为亚洲象,新的测年数据表明其时代大于5万年,依据牙齿测量数据和形态特征,本研究将其归入诺氏古菱齿象。目前已在泥河湾盆地发现百余个化石地点,鉴定出236种(包括未定属种)哺乳动物,分属于8目、32科和121属,其中38个属种(包括亚种)最初是以泥河湾化石材料而建立。总而言之,泥河湾盆地哺乳动物化石以早更新世者居多,并且化石材料保存完好;有些属种在欧亚大陆古北区第四纪哺乳动物群形成过程中发挥过重要作用,例如早期猛犸象、披毛犀、野牛及真枝角鹿等,还有直隶狼、貉及各种真马。泥河湾盆地由于河流和断层切割以及沉积相变等原因,导致各个化石点及史前考古遗址地层难以直接对比,更难全窥盆地内动物群演化的整体脉络;新的生物地层对比...  相似文献   

4.
20世纪80年代在桑干河盆地一带考察泥河湾层时,在山西省天镇县南高崖乡的台家坪、水冲口和大庄科的辛窑子沟一带发现了很多哺乳动物化石地点并出土了很多哺乳动物化石。最近对其中鹿科化石的研究鉴定出7个种:步氏麂(Muntiacus bohlini)、化德祖鹿相似种(Cervavitus cf. C. huadeensis)、山西轴鹿(Axis shansius)、华丽日本鹿(Nipponicervus elegans)、始麋鹿(Elaphurusdavidianuspredavidianus)、双叉麋鹿(E.bifurcatus)及赤鹿(Cervus(Elaphus)elaphus)。其中前6个种产自台家坪和水冲口化石地点的泥河湾组中,层位相当于欧洲的中、晚维拉方期,即早更新世,而赤鹿产自大庄科化石地点,层位目前还不确定,但可能也是泥河湾组。因此在辛窑子沟一带的早更新世目前发现的鹿科化石至少有6个种。其中的化德祖鹿相似种和山西轴鹿是从晚新近纪残留下来的种类,而步氏麂、华丽日本鹿、始麋鹿和双叉麋鹿是早更新世出现的新种类。如果大庄科地点的层位可以确定为早更新世的话,赤鹿的最早记录则可以回溯到早更新世,其鹿角的演化是始于无冰枝,然后出现冰枝。另外,在中国大陆和日本列岛都发现过麋鹿和日本鹿化石,进一步说明在早更新世期间海平面曾经下降很多,使得大陆的一些鹿类得以迁徙到列岛上。最后,数量较多的低冠鹿科化石标本指示桑干河盆地一带在早更新世存在一定范围的森林环境。  相似文献   

5.
狭义(或经典)泥河湾动物群主要产自桑干河北岸的下沙沟村周边,化石来源于不同地点;该动物群被作为我国北方早更新世的代表,但其绝对年代一直饱受争议,最新古地磁测年数据是2.2-1.7 MaBP。由于受河流及断层切割影响,泥河湾盆地内部不同区域尤其是桑干河两岸的地层对比,一直是个科学难题,其根本原因在于长期以来在桑干河南岸未发现重要化石点。最近,在桑干河南岸的岑家湾台地发现了山神庙咀化石点,目前已在此地点做过9次正规发掘,出土哺乳动物化石1526件,鉴定出25个种(含未定种),其中23种属于狭义泥河湾动物群的成员。由此看出,山神庙咀动物群的时代应当与狭义泥河湾动物群的时代接近,其地质年代应当不晚于1.7 MaBP。山神庙咀遗址与小长梁遗址隔沟相望,但其化石层稍高于小长梁文化层;山神庙咀动物群的研究结果还表明,小长梁遗址年代要比先前所测得的1.36 MaBP要早;小长梁周边的史前遗址的地质年代应当再做深入研究。小长梁地区的泥河湾层底部普遍存在砾石层,但其出现的水平位置以及砾石在分选和磨圆程度等方面都各不相同。调查清楚不同剖面中底砾层的分布状况及其性质,将会对本地区地层对比研究以及推断当时泥河湾盆地的古环境都将具有十分重要意义。  相似文献   

6.
泥河湾盆地上沙嘴石制品   总被引:1,自引:0,他引:1  
泥河湾盆地上沙嘴出土石制品34件,包括石核、石片、石器和断块,并伴随纳玛象头骨与马和犀等的牙齿化石。上沙嘴石制品最初发现于1972年,报道后在国内外引起强烈反响。1980年该地点的时代被修改为晚更新世。近年来的考察再次表明,上沙嘴地点就位于下更新统泥河湾组,且得到了古地磁测年为距今160~170万年的确认。  相似文献   

7.
河北泥河湾早更新世骨制品的初步观察   总被引:1,自引:1,他引:0  
本文记述了我馆收藏的原北疆博物院遗留下的38件骨制品。经查阅文献资料和初步观察可知;这批标本确属人工制品,它与泥河湾层出土的动物化石共存在于同一地点(主要是下沙沟),地质时代为早更新世。
这批材料的发现,具有重要的科学价值,它进一步证实了在泥河湾一带存在早更新世的原始人类,还证实了骨器也是原始人类的生产工具之一。  相似文献   

8.
周口店第一地点的犀类化石   总被引:3,自引:1,他引:2  
半个世纪以来,从北京周口店第一地点(‘北京人’化石产地)发掘的八大类哺乳动物化石,目前仅其中的犀类与象类尚未正式研究发表。这个问题受到国内外古生物学者的关注。因为自1928年以来,犀类材料虽未发表,而许多关于周口店第一地点的报道和论文,大都提到这里的化石动物群中有两种犀牛,主要的意见是梅氏犀与披毛犀。如所周知,梅氏犀是生活在温暖的间冰期的林栖犀牛,偶尔出现于草原但不栖息于气候严酷的草  相似文献   

9.
出土于内蒙古赤峰初头朗小南山地点的哺乳动物化石新材料有直隶犬(Canis chihliensis),泥河湾披毛犀(Coelodonta nihowanensis),中国长鼻三趾马(Hipparion(Proboscidipparion)sinense),三门马(Equus sanmeniensis),李氏野猪(Sus lydekkeri),湖麂相似种(Muntiacus cf.M.lacustris),山西轴鹿(Axis shansius),布氏真枝角鹿(Eucladoceros boulei),翁氏转角羚羊(Spirocerus cf.S.wongi)及古中华野牛(Bison palaeosinensis)。加上此前在初头朗东梁、东村北沟和东村南沟3个地点出土的标本,初头朗一带出土的哺乳动物化石种类增加到30个。初头朗4个地点的哺乳动物化石产自同一层位,属于同一个动物群。根据动物群的二元相似性系数,初头朗动物群在组成上最接近狭义泥河湾动物群。综合Brainerd-Robinson排序结果、动物群古老系数和动物群中绝灭种类的百分比,初头朗动物群的时代介于狭义泥河湾动物群和柳城巨猿洞动物群之间;而根据与相关动物群年龄值的对比,初头朗动物群的年龄值约在1.4–1.6 Ma之间。初头朗动物群中的食肉目种类有11个,但大多为小型种类。奇蹄目和偶蹄目种类的总和占动物群总数的一半,大多为体型较大的种类。该动物群中的嫩食者和林栖者指示当时存在一定范围的森林和林地;而动物群中的粗食者及开阔地栖息者指示当时存在面积较大的草原和草甸。初头朗动物群的大部分种类是喜温动物,喜冷种类只有鼠兔和披毛犀,因此当时的气候与现今大致相同。在地理位置上初头朗动物群是我国最靠北和最靠东的早更新世动物群,因此可以推荐为东北地区的早更新世哺乳动物群典型地点。  相似文献   

10.
出土于内蒙古赤峰初头朗小南山地点的哺乳动物化石新材料有直隶犬(Canis chihliensis),泥河湾披毛犀(Coelodonta nihowanensis),中国长鼻三趾马(Hipparion (Proboscidipparion) sinense),三门马(Equus sanmeniensis),李氏野猪(Sus lydekkeri),湖麂相似种(Muntiacus cf.M.lacustris),山西轴鹿(Axis shansius),布氏真枝角鹿(Eucladoceros boulei),翁氏转角羚羊(Spirocerus cf.S.wongi)及古中华野牛(Bison palaeosinensis).加上此前在初头朗东梁、东村北沟和东村南沟3个地点出土的标本,初头朗一带出土的哺乳动物化石种类增加到30个.初头朗4个地点的哺乳动物化石产自同一层位,属于同一个动物群.根据动物群的二元相似性系数,初头朗动物群在组成上最接近狭义泥河湾动物群.综合Brainerd-Robinson排序结果、动物群古老系数和动物群中绝灭种类的百分比,初头朗动物群的时代介于狭义泥河湾动物群和柳城巨猿洞动物群之间;而根据与相关动物群年龄值的对比,初头朗动物群的年龄值约在1.4-1.6 Ma之间.初头朗动物群中的食肉目种类有1 1个,但大多为小型种类.奇蹄目和偶蹄目种类的总和占动物群总数的一半,大多为体型较大的种类.该动物群中的嫩食者和林柄者指示当时存在一定范围的森林和林地;而动物群中的粗食者及开阔地栖息者指示当时存在面积较大的草原和草甸.初头朗动物群的大部分种类是喜温动物,喜冷种类只有鼠兔和披毛犀,因此当时的气候与现今大致相同.在地理位置上初头朗动物群是我国最靠北和最靠东的早更新世动物群,因此可以推荐为东北地区的早更新世哺乳动物群典型地点.  相似文献   

11.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

12.
13.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

14.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

15.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

16.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

17.
《Ibis》1894,36(3):447-460
  相似文献   

18.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

19.
We report 19 new species records for the faunal list of Coleoptera in New Brunswick, Canada, six of which are new records for the Maritime provinces, and one of which is new Canadian record. We also provide the first recent records for five additional species in New Brunswick. One new species of Stenotrachelidae, Cephaloon ungulare LeConte, is added to the New Brunswick faunal list. Additional records are provided for Cephaloon lepturides Newman, as well the first recent record of Nematoplus collaris LeConte. Two species of Oedemeridae, Asclera puncticollis (Say) and Asclera ruficollis (Say), are newly reported for New Brunswick, and additional locality and bionomic data are provided for Calopus angustus LeConte and Ditylus caeruleus (Randall). The records of Ditylus caerulus are the first recent records for the province. Three species of Meloidae, Epicauta pestifera Werner, Lytta sayi LeConte, and Meloe augustcollis Say are reported the first time for New Brunswick; Epicauta pestifera is newly recorded in Canada. Lacconotus punctatus LeConte and the family Mycteridaeis newly recorded for New Brunswick. The first recent records of Borus unicolor Say (Boridae) are reported from the province. One new species of Pythidae, Pytho siedlitzi Blair, and the first recent records of Pytho niger Kirby are added to the faunal list of New Brunswick. Three species of Pyrochroidae are newly reported for the province, including Pedilus canaliculatus (LeConte) and Pedilus elegans (Hentz), which are new for the Maritime provinces. Five species of Anthicidae and the first recent record of Anthicus cervinus LaFerté-Sénectére are newly reported for New Brunswick. Anthicus melancholicus LaFerté-Sénectère, Sapintus pubescens (LaFerté-Sénectère), Notoxus bifasciatus (LeConte), and Stereopalpus rufipes Casey are new to the Maritime provinces faunal list. Ambyderus granularis (LeConte) is removed from the faunal list of the province. Three species of Aderidae, Vanonus huronicus Casey, Zonantes fasciatus (Melsheimer), and Zonantes pallidusWerner, are newly recorded for New Brunswick; Zonantes fasciatus and Vanonus huronicus are new for the Maritime provinces' faunal list. Collection data, bionomic data, and distribution maps are presented for all these species.  相似文献   

20.
Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

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