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1.
王慧  要乐  林巍  王秋来 《古生物学报》2022,61(3):427-438
伴随晚泥盆世弗拉期–法门期之交的Kellwasser和泥盆纪–石炭纪之交的Hangenberg生物灭绝事件, 泥盆纪的主要造礁动物层孔海绵消失、珊瑚多样性急剧减少, 之后的早石炭世是造礁珊瑚的关键复苏期。贵州雅水剖面下石炭统维宪阶上司组发育了丰富的原位珊瑚层, 即层状珊瑚礁, 依据有孔虫化石确定珊瑚层的时代为维宪晚期。上司组珊瑚层主要由丛状复体四射珊瑚组成, 多样性低, 可识别出2属2种: Siphonodendron pauciradiale 和Stylostrotion pentalaxoidea。其中, S. pauciradiale广泛分布于西欧和北非地区维宪晚期的珊瑚礁中, 而S. pentalaxoidea分布局限, 目前仅见于华南板块。雅水剖面维宪晚期全球广布的造礁珊瑚S. pauciradiale的出现, 指示华南地区珊瑚礁的复苏演化过程与全球具有一致性。  相似文献   

2.
青海祁曼塔格山一带打柴沟组的珊瑚化石是近岸底栖、浅海相的块状复体四射珊瑚,属于晚石炭世至早二叠世过渡性质的Kepingophyllum珊瑚动物群,共7属19种,其中1新属和14新种。这些珊瑚的个体外壁由泡沫板和隔壁分化演变而成,它们在华南及西南地区相应时代中的珊瑚关系密切。  相似文献   

3.
青海祁曼塔格山一带打柴沟组的珊瑚化石是近岸底栖、浅海相的块状复体四射珊瑚,属于晚石炭世至早二叠世过渡性质的Kepingophyllum珊瑚动物群,共7属19种,其中1新属和14新种。这些珊瑚的个体外壁由泡沫板和隔壁分化演变而成,它们与华南及西南地区相应时代中的珊瑚关系密切。  相似文献   

4.
新疆北部准噶尔盆地周边石炭系广泛出露, 其中上石炭统发育海相火山—沉积序列, 包括西准噶尔地区的哈拉阿拉特组、阿腊德依克赛组, 东准噶尔地区的石钱滩组以及盆地南部的祁家沟组、奥尔吐组等。本文研究在上述各地层的灰岩层或夹层、碎屑岩中获得的四射珊瑚9属17种和床板珊瑚2属3种, 对石钱滩组中的3个新种进行了详细的系统古生物学描述。上述珊瑚化石的地质时代主要为巴什基尔期至莫斯科期。在珊瑚动物群的组成上, 哈拉阿拉特组中新发现Caninophyllum属分子, 结合盆地东、西部共同产出的床板珊瑚Cystodendropora 属分子, 说明整个准噶尔盆地周边的动物群面貌大致类似, 而西准噶尔地区的化石丰度、分异度显著低于盆地东部和东南部。综合前人资料, 目前在准噶尔盆地周边发现的珊瑚化石有约一半为地方性分子。本文认为研究区珊瑚化石的分布和组成特征与晚石炭世准噶尔洋走向封闭或半封闭的演化趋势密切相关。  相似文献   

5.
新疆北部准噶尔盆地周边石炭系广泛出露, 其中上石炭统发育海相火山—沉积序列, 包括西准噶尔地区的哈拉阿拉特组、阿腊德依克赛组, 东准噶尔地区的石钱滩组以及盆地南部的祁家沟组、奥尔吐组等。本文研究在上述各地层的灰岩层或夹层、碎屑岩中获得的四射珊瑚9属17种和床板珊瑚2属3种, 对石钱滩组中的3个新种进行了详细的系统古生物学描述。上述珊瑚化石的地质时代主要为巴什基尔期至莫斯科期。在珊瑚动物群的组成上, 哈拉阿拉特组中新发现Caninophyllum属分子, 结合盆地东、西部共同产出的床板珊瑚Cystodendropora 属分子, 说明整个准噶尔盆地周边的动物群面貌大致类似, 而西准噶尔地区的化石丰度、分异度显著低于盆地东部和东南部。综合前人资料, 目前在准噶尔盆地周边发现的珊瑚化石有约一半为地方性分子。本文认为研究区珊瑚化石的分布和组成特征与晚石炭世准噶尔洋走向封闭或半封闭的演化趋势密切相关。  相似文献   

6.
俞学光 《古生物学报》1991,30(4):420-438
本文描述苏皖地区和州组产四射珊瑚1新属、1新种;黄龙组产11属、13新种;船山组产6属、10新种且附栖霞组底部产1属、1新种。安徽广德县独山黄龙组、船山组出露良好,产四射珊瑚甚丰,可分3个化石带及2个亚带,与苏南的完全相当,唯苏南船山组上部的Parawentzellophyllum带在独山没有发现。  相似文献   

7.
广东南雄盆地上湖组介形类动物群及白垩-第三系界线   总被引:2,自引:0,他引:2  
张显球 《古生物学报》1992,31(6):678-702
南雄盆地上湖组介形类可划分为2个性质不同的动物群及4个化石带:下部为 Porpocypris 动物群,是以中生代属种为主,中、新生代属种混生的过渡性动物群,时代为晚白垩世最晚期;上部为 Cypris 动物群,以 Cypris 属占优势, Sinocypris 属开始出现, Cypridea 等古老属种绝灭为主要特征,时代为早—中古新世.根据介形类演化发展阶段和白垩纪末生物绝灭事件,南雄盆地白垩系与第三系的界线应划在 Porpocypris Cypris 动物群之间,即上湖组坪岭段与下惠段之间.  相似文献   

8.
福建宁化泉下黄龙组的四射珊瑚动物群*   总被引:4,自引:1,他引:3  
福建宁化泉下出露的晚石炭世碳酸盐地层以黄龙组最为发育,富含珊瑚、(竹蜓)类等化石。1983年秋,笔者等详细测制了该剖面,并逐层采集化石。经室内系统研究,共获四射珊瑚27属59种,包括2新属6新种。根据它们在地层中的分布规律,笔者建立了2个珊瑚组合,即下部Yinophyllum组合和上部Protoivanovia-Arachnastraea组合,后者可进一步划分为2个亚组合。如此丰富的四射珊瑚动物群在我国同期地层中尚不多见,这一四射珊瑚动物群的发现,对全面了解我国这一时期四射珊瑚动物群的总体面貌,对黄龙组的划分、对比都有较大的意义。本文描述的珊瑚化石均采自福建宁化泉上镇泉下石灰窑边,化石鉴定得到赵嘉明副研究员的帮助,化石照片由胡尚卿及解小健摄制,谨此一并致谢。  相似文献   

9.
刘发 《古生物学报》1992,31(2):249-255
本文描述了采自石门寨地区本溪组下段地层(含(竹蜓)灰岩之下)中的腕足动物化石并讨论了它的古生态环境。这个腕足动物群具有极大的丰度和很低的分异度,共3属5种,95%以上的个体为Derbyia,只有少数MeekellaOrbiculoidea。这种特殊的腕足动物组合反映当时本区处于非正常浅海环境,使得大多数底栖腕足动物无法生存。DerbyiaMeekella因具长的铰合线,外套膜能充分扩张、能吸收较多氧气,故能够生存、繁衍并形成极大丰度。这一腕足动物群未见于上部层位和其他地区,它的消失是古地理环境激剧变化引起的,是群落演替的结果。  相似文献   

10.
盛青怡 《古生物学报》2022,61(3):418-426
古盘虫类有孔虫是维宪早期到谢尔普霍夫早期最有用的生物地层标志微体化石之一, 广泛分布于正常浅海底栖环境。古盘虫超科里的平古盘虫亚科从早维宪中期开始出现, 具有最原始的壳壁结构。它将古盘虫类与其祖先假砂盘虫类联系起来。平古盘虫亚科壳壁主要是黑色微粒状。透明放射层局限在脐部或延伸覆盖到内部壳圈的壳缘。平古盘虫从何而来? 即古盘虫类的祖先问题, 一直存在争议。本文通过研究华南马栏边剖面石磴子组连续演化的LapparentidiscusViseidiscus, 证实了Lapparentidiscus是古盘虫类的祖先, 早期演化序列为 Lapparentidiscus talasicus–Viseidiscus eospirillinoides–Viseidiscus monstratus, 古盘虫类的透明放射层是以替代而非填充的形式出现的, 透明放射层逐渐替代黑色微粒层, 并从脐部逐步扩展到壳缘。  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.
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   

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14.
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   

15.
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   

16.
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   

17.
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   

18.
《Ibis》1894,36(3):447-460
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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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