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1.
A strange fossil described and illustrated in the present paper was collected by the writer in 1978 from the Huangshandong Member of the Lower Cambrian Tongying Formation in western Hubei. The material was preserved in greyish brown phosphoritic dolomites in association with elements of the Yangtze Micromolluscan Fauna, such as Tchangsichiton notabilus Yu and Sinuconus clypeus, Yu of Class Polyplacophora; Yangtzemerisma rarum Yu and Y.? cancellatum Yu of Class Merismoconchia; Yangtzeconus priscus Yu, Huangshandongoconus pileus Yu, Obtusoconus paucicostatus Yu, O. rostriptutea (Qian) and Spatuloconus rudis Yu of Class Monoplacophora; Bemella simplex Yu, Latouchlla of. memmorabilis Missarzhevsky, L. sanxiaesis Yu and L. lauta Yu of Class uncertain; Archaeospira ornata Yu, A. imbricata Yu and Cambrospira sinensis Yu of Class Gastropoda; Heraultipegma yunnanense He et Yang of Class Rostroconcbia: hyolithids and some other uncertain skeletal fossils. Although the systematic position of this peculiar fossil is unknown at present, it is inferred that this genus may be one of the typical primitive animal groups based on the characters of the shell and the spe cial spines. The shell is bilaterally symmetrical, elliptical in apical view; the dorsal side is roundly convex with three different forms of dorsal spines and several pairs of marginal spines on the anterior margin. Judged from the general morphological characters of the bilaterally symmetrical shell, these lower animals, generally speaking, have adapted themselves readily to different circumstances, and reduced resistance to any directional movement necessary for varied physiological activities. As to the function of the shell’s characteristics, the narrowly rounded side may serve as the anterior. Such a model of the body helps these animals go on with their benthonic creeping or swimming life. On the other hand, the dorsal spines are different from each other in shape, size, mode of arrangement and in number; especially, the end of the hook-shaped spines is generally curved outward, while the geniculate spines are oblique outward, and curved posteriorly all of a sudden. These structures of mechanism also provide us with the evidence that the narrowly rounded side serves as the anterior, while the opposite end as the posterior.It is of particular interest that this genus is somewhat similar to Phylum Mollusca, especially to the tryblidiids of Class Monoplacophora, in some morphological characters, such as: 1) the bilateral symmetry of the shell, 2) the outline elliptical in apical view and cap shaped in lateral view and 3) the dorsal side generally roundly convex. After careful study, it has been found that since this genus is strikingly different from monoplacopharans, may be it belongs to another interesting group of skeletal fossils. The reasons for this are: 1) in the former, there are many pairs of marginal spines on the anterior margin, while in monoplacophorans, no marginal spines can be seen; and 2) in this genus, the sculptures are different from each other in different areas, not only in shape and number, but also in the mode of arrangement, whereas in monoplacophorans, they are identical with each other in the same type and shape. Judged from the different forms of dorsal sculptures, this genus is comparatively similar to such uncertain shelly fossils as Lepidites Zhong, 1977 emend. Yu, 1987 and Xiadongoconus Yu, 1979 from the same horizon in the Yangtze Region of China, but differs from the latter two genera in the presence of marginal spines on the anterior margin. In addition, this new genus also differs from brachiopods and other skeletal fossils in the peculiar type of the shell. According to the above comparison, this genus is entirely different from all the classes of Phylum Mollusca, possibly representing another interesting group of skeletal fossils. It is impossible to determine the exact taxonomic position of this genus until more materials are available. 相似文献
2.
The Lower Cambrian univalved molluscs described in the present paper were collected in 1977—1978 by the geological parties from the base of the Xidashan Formation around Xidashan, Kuruktag, Xinjiang. The material is generally well-preserved and includes three species ascr bed to three genera, in which one genus and three species are new, namely, Helcionella xinjiangensis sp. nov., Eocyrtolites radiatus gen. et sp. nov., and Cyrtodiscus? kuruktagensis sp. nov..Among them, the genus Helcionella is a common from in the Cambrian in many parts of the world, and it also has been reported from the Cambrian formations of the North China Province and from the Huangshandong Member of the Lower Cambrian Tongying Formation of the Yangtze Provinnce in China. 相似文献
3.
Yu Xue-guang 《古生物学报》1991,(4):431-437
The speciments described in the present paper were collected from Hezhou, Huanglong and Chuanshan Formations in Jiangsu and Anhui. They belong to 17 genera (including 1 new genus) and 24 new species or subspecies, together with a new species from the lowermost part of the Chihsia Formation in Jiangsu. Based on characteristics of tetracorals, the Huanglong Formation (Moscovian) and the Chuanshan Formation (Sphaeroschwagerina Zone) at Dushan of Guangde, Anhui may be divided into four assemblage zones as follows: 相似文献
4.
Qiu Zhuding Institute of Vertebrate Paleontology Paleoanthropology Academia Sinica 《古脊椎动物学报》1987,(4)
<正> The fossils which form the subject of the present study were collected in the recent years from the middle Miocene Xiacaowan Formation at three sites, Songlinzhuang, Shuanggou and Zhengji of Sihong, Jiangsu. Most of the material from the first two sites have been reported previously as Prosciurus sp. (Li et al., 1983). Further study indicates that all the specimens mentioned and the M_1/2 previously assigned to Prosciurus? shantungensis Rensberger et Li (1986) are quite different from those of Prosciurus, but represent a new genus, Ansomys. In some features, the new form resembles Plesispermorphilus? descedens of Europe. For the two taxa a new subfamily Ansomyinae is created. It is morphologically intermediate between Meniscomyinae and Allomyinae, and may be the sister taxon of the higher aplodontids Allomyinae and Aplodontinae. 相似文献
5.
The cephalopods described in the present paper were mainly collected from the Badou Formation in the Zhangqiu district of central Shandong and the Fengfeng Formation in the Fengfeng city of southern Hebei by the writer and his colleagues in 1982-1983. They consist of 3 genera and 11 species, including 1 new genus and 9 new species. This paper also discusses previous reports on the Gonioceras from China and the contrast of the Badou Formation with the Fengfeng Formation as well as ecology, migration, origin and evolution of gonioceratids. 相似文献
6.
《古脊椎动物学报》1964,(4)
In this paper some vertebrate fossils collected from the Miocene at Puchen,Nan-king and at Hsiachaohwan,Shihung County,both in northern Kiangsu,are described;and the age of the localities as well as that of the “Hsiachaohwan fauna”are dis-cussed.1.The Puchen faunaThe fossils were found when siliceous sands were quarryed from a small hill at Pu-chen,a town in the Nanking district,some 8 kilometers on the northern bank of the 相似文献
7.
《古生物学报》1989,(4)
The Lower Cretaceous extensively distributed in Zhejiang contains abundant fossil plants. Since most of the fossils are so fragmentary, it is difficult to make a definite determination at specific level. The cuticle remains are very rare; only two species were reported (Chow and Tsao, 1979), namely, Pseudofrenelopsis parceramosa (Font.) Watson and P. papillosa (Chow et Tsao). This paper deals with several specimens of Gymnospermae, paying particular attention to the characteristics of the cuticular structure. These specimens belong to Nilssonia, Pseudofrenelopsis, Cupressinocladus and Brachyphyllum respectively, all being yielded from the four localities: 1. Suqin of Gymnospermae, paying particular attention to the characteristics of the cuticular structure. These specimens belong to Nihsonia, Pseudafrenelopsis, Cupressi-nocladus and Brachyphyllum respectively, all being yielded from the four localities: 1. Suqin of Xinchang County (Guantou Formation); 2. Shen-jia of Zhuji County (Shouchang Formation); 3. Pingshan of Lin'an County (Shouchang Formation); and 4. Laocun of Jiande County (Laocure Formation), as shown in the map of fossil localities in this paper. The subdivision of Lower Cretaceous and its correlation in both western and eastern Zhejiang are tabulated as follows (in descending order): 相似文献
8.
Among the graptolites collected by Unit 734 from the Lower Ordovician Qiaotingzi Formation (corresponding to the Ningkou Formation) at Xiayanzhai of Jishou, Hunan, more than ten specimens particularly chosen from the collection were handed over to the writer for. study. These spe cimens preserved as mere carbonaceous films in grey green slate belong to one new genus and the same new species named by the writer Jishougraptus mui gen. et sp. nov. in association with Didymograptus cf. praenuntius 相似文献
9.
In soumeastern Kansu,there is a vast area of metamorphosed sed(?)mentary rockscomposed of quartzites,crystallized limestones and slates with some intercalations ofhematites exposed in the valley of Lengputze to the north of Wen Xian,and in the valleyof Sunchiayuan to the west of Kang Xian.In 1944,Yeh and Kwan named the abovementioned strata at Lengputze Lupanchiao Quartzite and referred it to Lower Carbo-niferous.Lately(1959),by the discovery of Tabulata(Favosites sp.),C.H.Huang re-garded it as the upper part of the so-called Pikou Group of Lower Palaeozoic in age.While carrying on a field exploration in 1960,one of the writers,Kuo,collected a fewfossils from the same section and the corresponding strata in Kang Xian.They arelisted helow: 相似文献
10.
Sha Jin-geng 《古生物学报》1992,(3):309-312
This paper describes three new species of Pisidiidae, Pisidium (P.) zhushutangense, Sphaerium(S.) pyrum and Sphaerium (S.) fujianense, assoeiated with very abundant Plicatounio (P.) naktongensis Kobayashi et Suzuki, Plicatounio (P.) fujianensis Gu et Ma and Trigonioides (T.) quadratus Gu et Ma from the Lower Cretaceous upper Hekou Formation of Zhushutang, Hekou Basin, Ninghhua, Fujian. In Japan, the last two species, Sphaerium (S.) pyrum and Sphaerium (S.) fujianense, or their affinis coexist with each other in the upper Wakino Subgroup, the lower Wakamiya and upper Wakamiya Formations, and the lower Inakura Formation, Yamaji Shale, which very probably can be correlated with the upper Hekou Formation yielding these two species.The distinction between Pisidium and Sphaerium is summarized in Table I. 相似文献
11.
12.
In 1972, after frequent investigations on lithology, sedimentology and palaeontology (especially on palaeobotany), the Upper Triassic coal series (formerly the "Lalaqing Coal Series") in the Baoding area, southwestern Sichuan was previously divided by No. 1 Regional Geological Survey Team of Yunnan Province into two formations in ascending order as the Daqiaodi Formation, and the Daqing Formation (consisting of the Lower and Upper Members). 相似文献
13.
Tong Yongsheng Institute of Vertebrate Paleontology Paleoanthropology Academia SinicaLei Yizhen Yichang Institute of Geology Mineral Resources Ministry of Geology 《古脊椎动物学报》1987,(3)
<正> Among the fossil materials collected from the lower part of the Hetaoyuan Formation, exposed at Shipigou (namely Pishigou) of Xichuan County, Henan, are some specimens of the primitive lagomorphs. A left mandibular fragment of them was recovered by Lei, one of us, and is housed in the Yichang Institute of Geology and Mineral Resources, Ministry of Geology. Other isolated cheek teeth were got by means of screen-washing in the winter of 1984. In this paper these Eocene lagomorph fossils are described, and the homologies of the upper cheek tooth patterns of lagomorphs are discussed. 相似文献
14.
Adipose-derived stromal cells: Their identity and uses in clinical trials, an update 总被引:1,自引:0,他引:1
In adults, adipose tissue is abundant and can be easily sampled using liposuction. Largely involved in obesity and associated metabolic disorders, it is now described as a reservoir of immature stromal cells. These cells, called adipose-derived stromal cells (ADSCs) must be distinguished from the crude stromal vascular fraction (SVF) obtained after digestion of adipose tissue. ADSCs share many features with mesenchymal stem cells derived from bone marrow, including paracrine activity, but they also display some specific features, including a greater angiogenic potential. Their angiogenic properties as well as their paracrine activity suggest a putative tumor-promoting role for ADSCs although contradictory data have been published on this issue. Both SVF cells and ADSCs are currently being investigated in clinical trials in several fields (chronic inflammation, ischemic diseases, etc. ). Apart from a phase Ⅲ trial on the treatment of fistula,most of these are in phaseⅠand use autologous cells. In the near future, the end results of these trials should provide a great deal of data on the safety of ADSC use. 相似文献
15.
Mahmoud EIHefnawi Bangli Soliman Nourhan Abu-Shahba Marwa Amer 《基因组蛋白质组与生物信息学报(英文版)》2013,11(6):354-367
We aimed to shed new light on the roles of microRNAs (miRNAs) in liver cancer using an integrative in silico bioinformatics analysis. A new protocol for target prediction and functional analysis is presented and applied to the 26 highly differentially deregulated miRNAs in hepatocellular carcinoma. This framework comprises: (1) the overlap of prediction results by four out of five target prediction tools, including TargetScan, PicTar, miRanda, DIANA-microT and miRDB (combining machine-learning, alignment, interaction energy and statistical tests in order to minimize false positives), (2) evidence from previous microarray analysis on the expression of these targets, (3) gene ontology (GO) and pathway enrichment analysis of the miRNA targets and their pathways and (4) linking these results to oncogenesis and cancer hallmarks. This yielded new insights into the roles of miRNAs in cancer hallmarks. Here we presented several key targets and hundreds of new targets that are significantly enriched in many new cancer-related hallmarks. In addition, we also revealed some known and new oncogenic pathways for liver cancer. These included the famous MAPK, TGFβ and cell cycle pathways. New insights were also provided into Wnt signaling, prostate cancer, axon guidance and oocyte meiosis pathways. These signaling and developmental pathways crosstalk to regulate stem cell transformation and implicate a role of miRNAs in hepatic stem cell deregulation and cancer development. By analyzing their complete interactome, we proposed new categorization for some of these miRNAs as either tumor-suppressors or oncomiRs with dual roles. Therefore some of these miRNAs may be addressed as therapeutic targets or used as therapeutic agents. Such dual roles thus expand the view of miRNAs as active maintainers of cellular homeostasis. 相似文献
16.
《微体古生物学报》1984,(2)
Chinocythere was established as a new genus in 1978 based on fossil ostracodes found from the Palaeogene Shahejie and Dongying Formations along the coastal region of the Bohai Sea. It was also found from the Palaeogene Weizhou and Liushagang Formations of the continental shelf in the northern part of the South China Sea as well as from the early Oligocene Nadou Formation in the Baise basin in Guangxi. In historical geology, Chinocythere first appeared and flourished in Eocene and then gradually declined and became extinct in Oligocene. Despite of its narrow horizontal distribution and limited vertical extension in the geologic section, there are a great many of varieties in this genus, with up to 87 species already published representing the coastal region of the Bohai Sea alone, this in a sense, affords us an invaluable condition for the study of its evolution. 相似文献
17.
Mesenchymal stem cells(MSCs),derived from adult tissues,are multipotent progenitor cells,which hold greatpromise for regenerative medicine.Recent studies have shown that MSCs are immunosuppressive in vivo and in vitro inboth animals and humans.However,the mechanisms that govern these immune modulatory functions of MSCs remainlargely elusive.Some studies with bulk populations of MSCs indicated that soluble factors such as PGE2 and TGFβ areimportant,while others support a role for cell-cell contact.In this study,we intended to clarify these issues by examin-ing immunosuppressive effects of cloned MSCs.We derived MSC clones from mouse bone marrow and showed thatthe majority of these clones were able to differentiate into adipocytes and osteoblast-like cells.Importantly,cells fromthese clones exhibited strong inhibitory effects on TCR activation-induced T cell proliferation in vitro,and injection ofa small number of these cells promoted the survival of allogeneic skin grafts in mice.Conditioned medium from MSCcultures showed some inhibitory effect on anti-CD3 induced lymphocyte proliferation independent of PGE2 and TGFβ.In comparison,direct co-culture of MSCs with stimulated lymphocytes resulted in much stronger immunosuppressiveeffect.Interestingly,the suppression was bi-directional,as MSC proliferation was also reduced in the presence of lym-phocytes.Taking together,our findings with cloned MSCs demonstrate that these cells exert their immunosuppressiveeffects through both soluble factor(s)and cell-cell contact,and that lymphocytes and MSCs are mutually inhibitory ontheir respective proliferation. 相似文献
18.
The specimens referred to the Lungmachi Formation graptolites in the present paper were collected from Sanlangpu of Xixiang, Southern Shaanxi, consisting of 8 genera and 51 species or subspecies including 12 new species (see Table l in the Chinese text). This paper describes only the new species, with the rest being shown in tablesand plates. According to the present data on hand, the Lungmachi Formation graptolites studied here may be divided into 4 zones as follows:4. Orthograptus vesiculosus Zone (L_3)3. Parakidograptus acuminatus Zone (L_2)2. Glyptograptus persculptus Zone (L_1)1. Diplograptus bohemicus Zone (W_6)The first graptolite zone belongs to the Upper Ordovician, while the others to the Lower Silurian, indicating that the Lungmachi Formation in our studied area is a lithostratigraphic unit stridling across the Ordovician-Silurian boundary.This paper is in commemoration of the respectable late Prof. Mu En-zhi, to whom the writers are very much obliged for his kindness inguiding their scientific researches. 相似文献
19.
The palaeodiversity of flowering plants in Yunnan has been extensively interpreted from both a molecular and fossil perspective. However, for cryptogamic plants such as ferns, the palaeodiversity remains poorly known. In this study, we describe a new ferny fossil taxon, Drynaria lanpingensis sp. nov. Huang,Su et Zhou(Polypodiaceae), from the late Pliocene of northwestern Yunnan based on fragmentary frond and pinna with in situ spores. The frond is pinnatifid and the pinnae are entirely margined. The sori are arranged in one row on each side of the primary vein. The spores have a semicircular to bean-shaped equatorial view and a tuberculate surface. Taken together with previously described fossils, there are now representatives of three known fossil taxa of Drynaria from the late Pliocene of western Yunnan.These finds suggest that Drynaria diversity was considerable in the region at that time. As Drynaria is a shade-tolerant plant, growing preferably in wet conditions in the understory of forests, its extensive existence may indicate forest vegetation and humid climates in western Yunnan during the late Pliocene.This is in line with results from floristic investigations and palaeoclimatic reconstructions based on fossil floras. 相似文献
20.
The Upper Cambrian fossils were not known in South and SouthwesternChina before 1938,though a thick limestone series ranging from not less than100m to over one thousand meters known as the Ichang Limestone of the Gorgedistrict of the Yangtze and the Loushankwan Limestone of North Kueichou hasbeen partially referred by various authors to represent some part of the Upper 相似文献