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1.
鮻单脏吸虫,新种Haplosplanchnus lizae sp. nov. 和巨卵希氏单脏吸虫,新种Schikhobalotrema megaovus sp. nov. 检获于厦门集美附近海域棱鮻Liza carinatus肠道.鮻单脏吸虫,新种Haplosplanchnus lizae sp. nov与该属已知种的双腺单脏吸虫H. bivitellosus Zhukov,1971最为相似,它们都具有2列卵黄腺,但在卵黄腺的组成和虫卵大小方面存在明显差别;巨卵希氏单脏吸虫,新种Schikhobalotrema megaovus sp. nov. 与该属已知种的区别在于其虫卵0.130-0.12×0.096-0.120(0.133×0.108)特别大.    相似文献   

2.
Abstract

Six species of Siteroptes subgenus Siteroptoides—kneeboni (Wicht), mesembrinae (Canestrini), microsaniae n.sp., morelliae (Rack), muscarius n.sp., and portatus n.sp.—have been found in New Zealand. S. (S.) mesembrinae occurs on Niue Island also, and a further new species, pacificus, is recorded from Tonga. The phoretomorph females of all 7 species, the normal females of 4, the males of 3, and larvae of 2 are described and compared. The similarities and differences between normal and phoretomorph females are particularly noted. Besides kneeboni, 2 species described by Wicht but not occuring in New Zealand—athiasae and flechtmanni— are redescribed from type material and transferred to Siteroptes (Siteroptoides). Keys are given for normal females and Pediculaster-like phoretomorph females of Siteroptoides. Siteroptes mesembrinae subsimilis and S. ignotus altaicus are raised to species status. Diagnostically important measurements are given to help define the variation within and between species and morphs.  相似文献   

3.
Close paleontological examination of core —material from recent oil —wells and of rock —samples from outcrops in NW and SW Germany has made it possible to establish for this region the zone ofDactylioceras tenuicostatum (Young & Bird), the basal ammonite —zone of the Upper Liassic (Toarcien), and to define it stratigraphically. This means that the presence of this zone has now been stated for the whole area of the West-European liassic shelf, i. e., from southern Sweden to Portugal. Locally, the leading ammonites are accompanied by well preserved microfaunes which —still showing strong affinities to the fauna of the upper Domérien —contain already some species that might prove to be useful index fossils.  相似文献   

4.
实验以0.1%三氧化二钇(Y2O3)为外源指示剂, 用“70%基础饲料+30%待测饲料原料”的方法配制实验饲料。测定初始体重为(19.28±0.10) g的大口黑鲈(Micropterus salmoides)对荚膜甲基球菌蛋白、乙醇梭菌蛋白、黄粉虫粉、酶解大豆、小球藻和棉籽浓缩蛋白的干物质、蛋白质、脂肪、能量和氨基酸的表观消化率。结果显示, 6种实验原料干物质的表观消化率在37.27%—86.43%(荚膜甲基球菌蛋白>乙醇梭菌蛋白>酶解大豆>黄粉虫粉>小球藻>棉籽浓缩蛋白), 其中荚膜甲基球菌蛋白干物质的表观消化率最高, 乙醇梭菌蛋白次之, 黄粉虫粉、酶解大豆和小球藻之间没有显著性差异, 均显著高于棉籽浓缩蛋白(P<0.05); 蛋白质的表观消化率在79.97%—88.45%(荚膜甲基球菌蛋白>乙醇梭菌蛋白>黄粉虫粉>酶解大豆>小球藻>棉籽浓缩蛋白), 其中荚膜甲基球菌蛋白和乙醇梭菌蛋白均显著高于酶解大豆、小球藻和棉籽浓缩蛋白(P<0.05); 脂肪的表观消化率在51....  相似文献   

5.
Placoderms (Ptyctodontida), acanthodians (incl.Atopacanthus?ambrockensis n. sp.), actinopterygians, dipnoans and crossopterygians — including the first Middle Devonian osteolepids from the Rheinisches Schiefergebirge — are described from the lower Brandenberg Group of Hagen-Ambrock and Lasbeck (northern Sauerland, Northwest Germany). The composition of the fauna is similar to that of contemporaneous Scottish and Baltic Old Red localities, even though typical marine vertebrates are present too (e.g. selachians). This indicates — like the invertebrates — rather a marginal marine deposition.  相似文献   

6.
记吉林集安仙人洞的鹿类化石,兼述我国斑鹿化石的分类   总被引:4,自引:2,他引:2  
本文记述了产于吉林省集安县大路乡仙人洞洞穴堆积中的晚更新世鹿超科化石。这些化石可以分别归入麝科Moschidae和鹿科Cervidae,共四个种:Moschus moschiferus, Cervus (Sika) nippon horiulorum, Megaloceros ordosianus和Capreolus manchuricus。它们代表四种大小不同的鹿类动物,同为我国北方猛犸象-披毛犀动物群的成员。本文还指出斑鹿亚属的拉丁学名应为Sika,而不是Pseudaxis。产于我国的斑鹿化石可分为四个种。  相似文献   

7.
In the present study on enzymatic peptide bond formation the proteosynthetic potential of several proteases was explored. Trypsin, α-chymotrypsin, papain, carboxypeptidase Y (CPD-Y), and thermolysin served as catalysts for the protease-controlled synthesis of some fragments of melanocyte-stimulating hormones. To obviate possible proteolytic cleavage of preexisting peptide bonds—a drawback often encountered during enzymatic peptide syntheses—several expedients leading to the target peptides were developed. The enzymatic procedure enabled under mild conditions the preparation of the desired peptides whose amino acid composition may give rise to severe complications during conventional syntheses.  相似文献   

8.
A partial skeleton of the mastodont Mammut borsoni (Hays, 1834) (Proboscidea), was excavated from Pliocene deposits at Milia — Grevena, W. Macedonia, in 1996–1999. The skeleton includes substantial portions of the skull — maxillary area — with left and right molar series (M2 + M3); with the longest upper tusks ever found in Greece (4.39 m); the most complete mandible with left and right molar series (M2 + M3) and two lower incisor tusks, as well as post-cranial skeleton. It represents a very large adult of about 40 years in age. The high age of the finding is partly corroborated by ESR dating studies of tooth enamel, indicating an age probably beyond the upper dating range of this technique (approx. 800 000 years). The evolutionary position of this specimen among mammutids is also discussed.  相似文献   

9.
All of the 166 Clarias gariepinus catfishes in Lake Tana, Ethiopia, were examined for trematode infestation in 2006—2009. Seven trematode species—Eumasenia bangweulensis, Astiotrema reniferum, Orientocreadium batrachoides, Paralecithodendrium chilostomum, Phyllodistomum bavuri, P. tana, and Cladorchiidae gen. sp.—as adult were found. The common catfish parasites were Eumasenia bangweulensis (20% prevalence and 1—62 intensity of invasion), Orientocreadium batrachoides (30% prevalence and 1–31 intensity of invasion), Phyllodistomum bavuri (24.8% prevalence and 1–8 intensity of invasion), Ph. tana (17.6% prevalence and 1–23 intensity of invasion), and Ph. bavuri. Astiotrema reniferum (three specimens were only found) was a rare species; Paralecithodendrium chilostomum was an accidental parasite of catfish. All these trematodes were first recorded in Ethiopia and Eastern Africa.  相似文献   

10.
Blood groups in 2,935 Roms (Gypsies) of East Slovakia show the following frequencies of phenotypes and genes: A1A2BO phenotypes: A1 — 32.91%, A2 — 2.42%, B — 25.21%, O — 30.15%, A1B — 8.45%, A2B — 0.85%, A1 — 0.2363, A2 — 0.0217, B — 0.1929, O — 0.5491. MN phenotypes: M — 27.16%, MN — 51.60%, N — 21.23%; m — 0.5297, n — 0.4703. RH phenotypes: Rh positive — 89.54%, Rh negative — 10.46%; Rh – (D) — 0.6766, Rh (d) 0.3234. The frequencies are contrasted with those of other inhabitants, non-Roms of East Slovakia.  相似文献   

11.
Die Chromosomenzahlen von den tschechoslowakischen Sippen der GattungKnautia L. sind angegeben:K. drymeia Heuffel subsp.drymeia—2n = 40 (41,42),K. slovaca ?těpánek— 2n = 20,K. arvensis (L.)Coulter subsp.arvensis—2n = 20, 40 (39, 41),K. arvensis (L.)Coulter s. 1.—2n = 20,K. kitaibelii (Schult.) Borbás—2n = 20 (39, 41),K. dipsacifolia Kreutzer subsp.dipsacifolia—2n = 60,K. dipsacifolia agg.—2n = 40, 50, 60. Keine taxonomisch wertvolle morphologische Unterschiede zwischen diploiden und tetraploiden Zytotypen vonK. arvensis subsp.arvensis wurden gefunden. Für die Populationen von Pflanzen, deren Morphologierauf Kreuzung oder Introgression zwischen tetraploiden Sippen (K. arvensis subsp.arvensis—4x,K. drymeia subsp.drymeia, K. kitaibelii undK. dipsacifolia agg.) zeigt, wurden ím Einklang mit dieser Voraussetzung die tetraploiden Chromosomenzahlen—2n = 40 (39, 41)— festgestellt. Einige ungelöste taxonomische Fragen hauptsächlich über die diploiden Populationen vonK. arvensis s. l. in Böhmen und überK. dipsacifolia agg. in den Westkarpaten werden diskutiert.  相似文献   

12.
Sedimentation rates of organic and inorganic matter, chlorophyll a, P fractions, Ca, Mn, Fe and Al, were determined by sediment traps in a tropical oligo‐mesotrophic reservoir of São Paulo (Brazil). Vertical profiles of the sediments were analyzed for organic content, metals, P and surface P fraction composition. Estimated mean sedimentation rates, corrected for resuspension were: total solids, 1068 g m—2 y—1 (OM = 44.7%); chlorophyll a, 2.1 g m—2 y—1 and total phosphorus, 2.9 g m—2 y—1. The predominant P fraction in the settling flux was associated with aluminum minerals while surface sediments were dominated by organic P. The reservoir exhibited low sediment retention of P (13.0%), Al (9.9%), Fe (9.9%), Mn (1.4%) and Ca (traces), compared to trap sedimentation. This feature was related with a high vertical dynamics (resuspension and bottom release) and with the low retention time of the system.  相似文献   

13.
Fossil puparia of the subarctic blowfly P. terraenovae which were found in the skull and horn-core cavities of a “steppe wisent” (Bison priscus) are described. The steppe wisent was discovered in coarse fluviatile deposits overlying Eocene marine sediments at Zemst in the province of Brabant (Belgium), during excavations for the new sluice in the Brussels-Rupel Canal. Other faunal remains collected are rhinoceros — woolly rhinoceros, Coelodonta antiquitatis (?) — and proboscidian — woolly mammoth, Elephas primigenius (?). Geological and palaeontological data indicate that the deposits and their contents were probably formed during the Late Eemian under a cold temperature climate. An attempt is made to reconstruct the sequence of events leading to the association of empty blowfly puparia and the skull.  相似文献   

14.
Long non‐coding RNAs have become the focus of considerable interest over the past few years. Intriguing novel functions have been reported for lincRNAs. Three recent papers identify lincRNAs that work in a more conventional way—encoding protein—in each case a small polypeptide with an interesting biological activity (Magny et al, 2013 ; Pauli et al, 2014 ), (Bazzini et al, 2014 ).  相似文献   

15.
In the interior of northeastern Brazil there occurs the Santana Formation of Aptian age, composed lithologically of three members: Crato — an alternation of thin limestones and shales; Ipubi — gypsum; and Romualdo — almost pure limestone. The formation is very fossiliferous; pollen, plant remains, ostracodes, conchostracans, mollusks, echinoids, fishes and a few reptiles. The fishes and reptiles occur in limestone concretions. All data on sediment character and on fossils have been considered together for the interpretation of the palaeoenvironment of the formation.It was concluded that at the time of the Crato Member the deposition occurred in shallow lakes and swamps. Later (Ipubi Member), a marine invasion took place during a time of dry climate, causing anhydrite precipitation. Gradually the connection with the sea became obstructed so that the environment at the end of the depositional period became once more one of fresh water (Romualdo Member). Faunal assemblages and sediments point to a fairly great supply of river water during the whole time of basin deposition, under warm and dry climatic conditions. The connection with the sea persisted for a rather short period.  相似文献   

16.
The redox potential of the active Fe(III) complex of bleomycin (BLM), which is a DNA cleaving species, was measured by cyclic voltammetry at 25 °C under a hydrogen atmosphere. The cyclic voltammogram showed the reversible one-electron Fe(III)/Fe(II) coupled redox reaction at −0.225 V versus SCE. Under the same conditions the redox potentials of the iso-BLM—Fe(III) complex and the deglyco-BLM—Fe(III) complex were also observed, but the cyclic voltammogram for the inactive Fe(III) complex of BLM could not be obtained.  相似文献   

17.
通过形态观察和分子分析相结合的方法,对青岛(模式标本产地)产的帚状蜈蚣藻(Grateloupia fastigiata Li et Ding)进行了重新鉴定,结果表明:①藻体为深紫红色,高9-26 cm,基部呈圆柱状,1-2回不规则羽状分枝,皮层厚度为85-160 μm,由8-11层细胞构成;助细胞生殖枝丛为典型的Grateloupia型,果胞枝生殖枝丛主枝由6个细胞组成,辅助细胞生殖枝丛主枝由5个细胞组成(6cpb-5auxb型),与亚洲蜈蚣藻(G.asiatica Kawaguchi et Wang)一致。②基于rbcL基因序列构建的系统树显示:本研究的10个帚状蜈蚣藻样本与青岛产的亚洲蜈蚣藻之间无碱基差异,形成独立的进化支,与大连石槽、石庙子产的亚洲蜈蚣藻的碱基差异均为1 bp(0.08%),与日本、韩国产的亚洲蜈蚣藻的碱基差异分别为2 bp(0.16%)、3 bp(0.24%),均属于种内差异,与Grateloupia clade I中蜈蚣藻属内其他种的碱基差异为18(1.47%)-76 bp(6.19%),均属于种间差异。通过形态观察和rbcL基因序列分析,认为帚状蜈蚣藻与亚洲蜈蚣藻为同一种,将帚状蜈蚣藻作为亚洲蜈蚣藻的异名。  相似文献   

18.
Defining subpopulations using genetics has traditionally used data from microsatellite markers to investigate population structure; however, single‐nucleotide polymorphisms (SNPs) have emerged as a tool for detection of fine‐scale structure. In Hudson Bay, Canada, three polar bear (Ursus maritimus) subpopulations (Foxe Basin (FB), Southern Hudson Bay (SH), and Western Hudson Bay (WH)) have been delineated based on mark–recapture studies, radiotelemetry and satellite telemetry, return of marked animals in the subsistence harvest, and population genetics using microsatellites. We used SNPs to detect fine‐scale population structure in polar bears from the Hudson Bay region and compared our results to the current designations using 414 individuals genotyped at 2,603 SNPs. Analyses based on discriminant analysis of principal components (DAPC) and STRUCTURE support the presence of four genetic clusters: (i) Western—including individuals sampled in WH, SH (excluding Akimiski Island in James Bay), and southern FB (south of Southampton Island); (ii) Northern—individuals sampled in northern FB (Baffin Island) and Davis Strait (DS) (Labrador coast); (iii) Southeast—individuals from SH (Akimiski Island in James Bay); and (iv) Northeast—individuals from DS (Baffin Island). Population structure differed from microsatellite studies and current management designations demonstrating the value of using SNPs for fine‐scale population delineation in polar bears.  相似文献   

19.
The volvocine green algal genus Volvox includes ~20 species with diverse sizes (in terms of both diameter and cell number), morphologies, and developmental programs. Two suites of characters are shared among distantly related lineages within Volvox. The traits characteristic of all species of Volvox—large (>500) numbers of small somatic cells, much smaller numbers of reproductive cells, and oogamy in sexual reproduction—have three or possibly four separate origins. In addition, some species have evolved a suite of developmental characters that differs from the ancestral developmental program. Most multicellular volvocine algae, including some species of Volvox, share an unusual pattern of cell division known as palintomy or multiple fission. Asexual reproductive cells (gonidia) grow up to many times their initial size and then divide several times in rapid succession, with little or no growth between divisions. Three separate Volvox lineages have evolved a reduced form of palintomy in which reproductive cells are small and grow between cell divisions. In each case, these changes are accompanied by a reduction in the rate of cell division and by a requirement of light for cell division to occur. Thus, two suites of characters—those characteristic of all Volvox species and those related to reduced palintomy—have each evolved convergently or in parallel in lineages that diverged at least 175 million years ago (mya).  相似文献   

20.
《Anaerobe》2002,8(1):17-22
Bacteroides fragilis strains isolated from faeces of diarrhoeic and healthy children were studied by polymerase chain reaction (PCR), in order to characterise them as enterotoxigenic B. fragilis -ETBF—if they have one of the three bft gene alleles (pattern I) or as non-toxigenic B. fragilis—NTBF—if there was an absence of bft gene alleles and specific sites (flanking region of B. fragilis Pathogenicity Island—BfPAI) (pattern II NTBF) or absence of alleles, but the presence of this specific sites (pattern III NTBF). All strains were previously screened for cytotoxic activity. ETBF was detected in 1.5% (1/66) of the samples, in which we could verify, concomitantly, the presence of Escherichia coli enteroaggregative (EAEC). Due to these data, ETBF could not be associated with diarrhoea. A large number of pattern III NTBF strains were observed, which could suggest future changes in the phenotype of enterovirulence of B. fragilis species in our country. These populations were also analysed by using AP-PCR and a great heterogeneity could be observed. We were not able to make a correlation between enterovirulence patterns and genetic types.  相似文献   

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