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1.
The pigmentary system of the skin from adult specimens of the black alpine salamander Salamandra atra atra was investigated by light microscope, electron microscope, and biochemical studies. Results were compared with those obtained in previous study of the subspecies Salamandra atra aurorae. Unlike Salamandra atra aurorae, which presents epidermal xanthophores and iridophores, Salamandra atra atra is completely melanized, presenting only epidermal and dermal melanophores. The melanosomes in both the epidermis and the dermis appear to derive from a multivesicular premelanosome similar to that in the goldfish, and the epidermal melanosomes are smaller than those in the dermis. Premelanosomes with an internal lamellar matrix were not observed. The biochemical results have shown that in the ethanol extracts obtained from the skin in toto and from the melanosomes, pteridines and flavins are always present and are the same as those extracted from the black skin areas of Salamandra atra aurorae.  相似文献   

2.
Detailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra(Naja atra) is a large sized, venomous snake commonly found in southeastern China, where it causes a heavy burden of snakebites. To examine the effects of various factors(morphology, sex, age, season, and geographical origin) on the venom yield in this snake, we collected venom samples of 446 individuals(426 adults and 20 neonates) from 10 populations of N. atra over an eightyear period. We used two variables, lyophilized venom mass(venom yield) and solid content of venom(% solids), to quantify the venom yield. We used linear regression analysis to check if venom yield was related to morphological factors, one-way ANOVA and one-way ANCOVA to detect the sexual, ontogenetic, and geographic variation in venom yield, and repeated-measures ANOVA to examine seasonal shifts in venom yield. Our results indicate that venom yield of N. atra is positively related to the morphological traits examined, with male snakes expelling more venom than females. Venom yield in N. atra was age-related, with elder snakes always expelling more venom than younger ones. Geographic variation in venom yield was also observed, while seasonal variation was not. The solid content of venom was lower in males than in females, but this was not related to morphology, season, age, or geography. Our findings suggest that venom yield in N. atra is influenced by multiple factors, as well as by the interactions among these factors.  相似文献   

3.
4.
The pigmentary system of the skin from adult specimens of the black alpine salamander Salamandra atra atra was investigated by light microscope, electron microscope, and biochemical studies. Results were compared with those obtained in previous study of the subspecies Salamandra atra aurorae. Unlike Salamandra atra aurorae, which presents epidermal xanthophores and iridophores, Salamandra atra atra is completely melanized, presenting only epidermal and dermal melanophores. The melanosomes in both the epidermis and the dermis appear to derive from a multivesicular premelanosome similar to that in the goldfish, and the epidermal melanosomes are smaller than those in the dermis. Premelanosomes with an internal lamellar matrix were not observed. The biochemical results have shown that in the ethanol extracts obtained from the skin in toto and from the melanosomes, pteridines and flavins are always present and are the same as those extracted from the black skin areas of Salamandra atra aurorae.  相似文献   

5.
本文采用日立835-50型氨基酸自动分析仪测定了广东眼镜蛇蛇毒与眼镜王蛇蛇毒的氨基酸成分,结果表明两种蛇毒的氨基酸组成基本相同,但多种氨基酸的含量存在明显差异,为蛇毒鉴别和质控提供实验依据。  相似文献   

6.
Li CL  Wang CC  Keith D  Yang PS 《ZooKeys》2012,(177):37-48
Two new species of the Oriental scarab genus Tocama Reitter, 1902, Tocama laosensissp. n. and Tocama procerasp. n., are described from Indochina with diagnoses, distributions, remarks and illustrations. A key to the species of the genus is provided with a checklist with several nomenclatural changes: Hoplosternus tonkinensis Moser, 1913 is transferred to Tocama; Hoplosternus pygidialis Moser, 1915 syn. n., Tocama atra atra Keith, 2006 syn. n. and Tocama atra reichenbachi Keith, 2007 syn. n. = Tocama tonkinensis (Moser).  相似文献   

7.
Abstract:  A mass rearing method for Erigone atra (Blackwall) (Araneae: Linyphiidae) allowing continuous laboratory rearing is described. Twenty 1–2-day old spiderlings were kept together in plastic boxes, which were filled with soil containing a culture of the Collembola species, Lepidocyrtus lanuginosus (Gmelin) (Entomobryidae), and serving the spiders as a continuous available prey source. Once per week vestigial-wing fruit flies of Drosophila melanogaster Meigen (Diptera: Drosophilidae) were provided as additional prey. In addition, the rearing boxes were filled with wood-wool serving spiders as points of contact for their webs. After 3–5 weeks most of the spiderlings developed to adults, which were separated individually into glass tubes filled with soil and Collembola until all of them became adult. To produce a new generation of spiders 20–40 adult/subadult spiders originating from different mass rearing boxes were brought together and kept and fed in the same way as the spiderlings. Within a few days females started to produce eggsacs. The eggsacs were transferred into glass tubes filled with a layer of moist plaster of Paris until the spiderlings hatched, which were then bred as described above. Erigone atra was bred over 12 generations within a period of 2 years. The mean rearing success (from 1 to 2-day-old spiderlings to adults) was 59.3%. Decreasing rearing success, decrease of fecundity or decrease of adult spider size were not observed. Advantages and use of the mass rearing method are discussed in relation to rearing methods for other spiders.  相似文献   

8.
In this study we explored electrophoretic profiles, enzymatic activities and immunoreactivity of neonate and adult venoms from two snakes (Naja atra and Deinagkistrodon acutus) coexisting in southeastern China. Age-related variation in electrophoretic profiles was found in both species and proteolytic and fibrinogenolytic activity was higher in neonate than adult venoms. Neonate D. acutus venom had higher 5' nucleotidase, PLA2, hyaluronidase and gelatinolytie activity, but lower esterolytic activity, than adult venom. Neonate and adult D. acutus venoms showed identical phosphomonoesterase, LAO and fibrinolytic activities. Neonate N. atra venom had higher phosphomonoesterase and LAO activity, but lower 5' nucleotidase, PLA2, hyaluronidase and Ache activities than adult venom. Neonate and adult N. atra venoms showed similar gelatinolytic activity. Further, age-dependent immunoreactivity was found in both species, and cross-reactions between homologous venoms and antiserums were closely related to venom composition. We speculate that age-related variation in venom characteristics is possibly driven by evolutionary forces associated with ontogenetic shifts in dietary habits, competition and predation pressure.  相似文献   

9.
The inventory of coot (Fulico atra) ectoparasites during wintering season (October 2004-March 2005) has been carried out from 17 individuals captured in lake Tonga. Results show that mites are the most abundant parasites (65.6%), followed by lice (Pseudomenopon pilosum, Rallicolo fulicae, Fullicofulo lurida, Incidifrons fulicae, Laemobothrion atrum) 34.4% and leeches (Theromyzone sp) with 0.05%. All individuals were infested with lice, 82.4% with mites and 41.2% with leeches.  相似文献   

10.
Flightless rails were once ubiquitous in the avifauna of Pacific oceanic islands. Most species have become extinct since human colonization of islands began about 2000 years ago. In this study, we use mitochondrial sequence data to estimate the phylogenetic relationships and ages of four species of flightless insular rails in the genus Porzana : palmeri , from Laysan Island in the Hawaiian archipelago; sandwichensis , from the island of Hawaii; monasa , from Kosrae Island in Micronesia; and atra , from Henderson Island in the Pitcairn group. Although all four species survived into historic times, all but atra are now extinct. The optimal trees show that palmeri is descended from Porzana pusilla , a volant crake distributed widely throughout the Old World. Porzana sandwichensis , P. monasa , and P. atra are each descended from the lineage leading to P. tabuensis , a volant rail widespread in northern and eastern Australia and on islands north to Micronesia and the Philippines and east through Polynesia. Loss of flight appears to have evolved rapidly in these insular rails, based on both sequence divergence values and data on the ages of the islands. In the case of the Laysan Rail ( palmeri ), divergences including loss of flight probably evolved in less than 125,000 years .  相似文献   

11.
Fifty individuals of the endemic Alpine salamander, Salamandra atra, representing 13 populations throughout the range of the two currently recognized subspecies, atra and aurorae, were examined for sequence variation in a large portion (1050 bp) of the mitochondrial cytochrome b gene. We revealed a large number of mitochondrial DNA (mtDNA) haplotypes (10). Interpopulation sequence divergence was very low, ranging from 0 to 3.1%. The relationships among haplotypes were poorly resolved. The divergence time estimate between several mtDNA haplotypes suggested a pre-Pleistocene differentiation approximately 3 million years ago. Moreover, the impact of the Pleistocene glaciations on the phylogeographical patterns appears to have been secondary, although a somewhat reduced genetic variability was found in populations living in areas that were directly affected by the glaciation.  相似文献   

12.
The uterine epithelium of the viviparous Salamandra atra and the ovoviviparous Salamandra salamandra was studied in non pregnant and ovulating females and in females during different stages of pregnancy. The epithelium of both species is organized in a monolayer. The epithelial cells are characterized by a moderate secretory activity, a variable amount of apical granules which include PAS-positive material and by some apical and basal exo- or endocytotic vesicles. Adjacent cells are joined by junctional complexes. The lateral surfaces form a tortuous boundary with adjoining cells which suggest that the epithelium is involved in transport. Sporadic light cells possess highly variable cytoplasmic inclusions and are not joined with neighbouring cells. Possibly they represent migratory cells. The entire epithelium, except for a small cranial portion of the uterus in S. atra, undergoes no remarkable morphological changes during the different physiological stages examined except that flattened cells seem to be more numerous in pregnant females. The results are discussed with regard to the possible supply of the developing young by the mother.  相似文献   

13.
A less-cytotoxic polypeptide, designated as LCBP, was isolated from the venom of Naja naja by gel filtration on Sephadex G-50 followed by CM-cellulose chromatography. The cytotoxicity toward Yoshida sarcoma cells and lethal toxicity toward mice of LCBP were both one order of magnitude lower than that of cytotoxins and that of toxin A, respectively. LCBP is a single polypeptide consisting of 61 amino acid residues with four intramolecular disulfide linkages, and the amino acid sequence is the same as that of cardiotoxin-like basic polypeptide (CLBP) isolated from the venom of Naja naja atra. This is the first time that the same polypeptides were isolated from different cobra venoms.  相似文献   

14.
In the Volga and Don river basins, 17 stonefly species are known: 16 from the Volga, and 6 from the Don basin. The fauna is dominated by the species with wide, European (Isogenus nubecula, Nemoura flexuosa, N. dubitans, Amphinemura sulcicollis, Brachyptera braueri, Isoperla difformis, I. grammatica, Leuctra hippopus, Xanthoperla apicalis, Siphonoperla burmeisteri) and Transpalaearctic ranges (Taeniorterykh nebulosa, Nemurella pictetii, Amphinemura borealis, Nemoura cinerea, Capnia atra, Leuctra fusca, Isoperla obscura).  相似文献   

15.
The genus Phora (Diptera, Phoridae) includes more than 50 species widely distributed in temperate regions of Eurasia and Africa. Taxonomic identification of most species is based upon the morphology of the male hypopygium: hence for many species, including the type species of the genus, females are unknown. We used mitochondrial 16S ribosomal RNA sequences to match males with previously unidentified females from Phora atra , P. stictica , and P. holosericea . We then identified morphological characters that allow identification of females of P. atra and P. stictica without recourse to DNA sequencing. Our results show that small scale sequencing can aid in the development of taxonomic characters for use in the field to identify previously cryptic females. This iterative method of identifying populations genetically followed by re-examination of morphology should allow development of better keys for rapid identification of heretofore cryptic populations of insects. We also found that sequences from individual of P. holosericea from Cambridge, England and Malakhovka, Russia, were more similar to each other than to sequences from a conspecific fly also collected in Cambridge. This result suggests that there is previously un-suspected population structuring in this species.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 267–273.  相似文献   

16.
鸡血清与卵黄中抗中华眼镜蛇毒IgY动态变化研究   总被引:2,自引:0,他引:2  
刘四红  孔天翰 《蛇志》2006,18(4):261-264
目的探索特异性IgY的产生和变化规律。方法用眼镜蛇毒原毒免疫产蛋母鸡,ELISA定期检测卵黄中的抗体效价变化,小鼠体外中和实验检测其生物活性。第1次免疫40周后,眼镜蛇毒攻击已免疫母鸡,检测攻击前后鸡血清中抗体效价变化情况,未经眼镜蛇毒免疫的母鸡作阴性对照。结果经免疫后第7天蛋黄中即可检测到抗体,经多次加强免疫,40周时蛋黄中还能保持高效价的抗体,通过分离纯化,此抗体可保护实验小鼠免受4 LD50眼镜蛇毒的攻击;同时,鸡血清中也保留着较高效价的抗体,可中和4 LD50以上的眼镜蛇毒。结论用眼镜蛇毒免疫鸡,经多次加强免疫,卵黄和鸡血清中可持久保持高效价的特异性抗体,初步检测此抗体可中和4 LD50的蛇毒。  相似文献   

17.
As the preparation of high titer antiserum against Naja naja atra venom is a time-consuming process, attempts were made to develop a immunization procedure for producing highly potent antiserums within a short period. Rabbits were immunized for 12 weeks with (1) whole venom as used routinely in our Institute, (II) whole venom adsorbed on carboxymethyl-cellulose (CMC) and mixed with Freund's complete adjuvant and (III) neurotoxin adsorbed on CMC and adjuvant mixture followed by CMC-whole venom-adjuvant mixture. The results showed that one ml of the antiserum prepared by method (III) could neutralize 445 LD50 of whole venom, in other words, its potency was 4 and 40 times higher than those prepared by methods (II) and (I), respectively.  相似文献   

18.
Tryptophan (Trp) fluorescence of two phospholipases A2 (PLA2) from Naja naja atra and Naja nigricollis snake venoms was quenched by acrylamide and iodide. Trp residues in N. naja atra PLA2 were equally accessible to acrylamide and iodide. Iodide quenching studies indicate that there are two classes of Trp fluorophores in N. nigricollis CMS-9. The accessible class consists of Trp-18 and Trp-19. Removal of the N-terminal octapeptide caused a perturbation of the micro-environment of the Trp residues in the PLA2 enzymes. The presence of a substrate lowers the susceptibility of the Trp residues to iodide quenching in N. naja atra PLA2, suggesting that all three Trp residues are at the substrate binding site, but in N. nigricollis CMS-9 Trp-18 and Trp-19 are related to substrate binding.  相似文献   

19.
刘嵩  刘敏  熊克仁 《蛇志》2011,23(2):102-104,110
目的 探讨眼镜蛇毒对成年大鼠下托巢蛋白(Nestin)阳性神经细胞表达的影响.方法 采用免疫组织化学方法,观察并比较Nestin阳性细胞在眼镜蛇毒组、生理盐水组、正常对照组大鼠下托的表达.结果 眼镜蛇毒组大鼠下托Nestin阳性神经细胞比生理盐水组、正常对照组表达明显增强(P〈0.01).结论眼镜蛇毒对大鼠下托Nestin表达有上调作用.  相似文献   

20.
李怀斌  徐臣利  王丽发  熊克仁 《蛇志》2011,23(2):93-95,131
目的 探讨眼镜蛇毒对大鼠脑桥网状核c-fos阳性神经元表达的影响.方法 采用免疫组织化学方法,观察并比较c-fos阳性神经元在眼镜蛇毒组、生理盐水组、正常对照组大鼠脑桥网状核的表达.结果 眼镜蛇毒组大鼠脑桥网状核c-fos阳性神经元比生理盐水组、正常对照组表达明显增强(P<0.05).结论眼镜蛇毒对大鼠脑桥网状核c-f...  相似文献   

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