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1.
Axillary shoot proliferation was induced in vitro from shoot explants of greenhouse grown candellila (Euphorbia antisyphilitica Zucc). Optimum shoot proliferation was obtained by supplementing a modified Murashige and Skoog [7] medium with 0.13 M naphthalene-acetic acid and 4.44 M 6-benzylaminopurine. Rooting occurred on 100% of shoots transferred to a medium containing half strength salts supplemented with 0.49 M indole-3-butyric acid. Fully rooted plants were transferred to potting soil and established under greenhouse conditions without special acclimatization techniques.  相似文献   

2.
Summary Short-term ACTH treatment provoked a decrease in volume of the lipid-droplet compartment in rat zona glomerulosa cells, and a rise in plasma and intracellular concentrations of corticosterone and aldosterone. It enhanced activities of 3-hydroxysteroid dehydrogenase (3HSD), 11-hydroxylase (11OH) and 18-hydroxylase (18OH). Long-term ACTH administration produced a hypertrophy of the zona glomerulosa and its parenchymal cells, a result of the increase in volume of the smooth endoplasmic reticulum and the mitochondrial compartment. The surface area per cell of mitochondrial inner membranes increased; the tubular cristae were transformed into a homogeneous population of vesicles. The plasma and intracellular concentrations of corticosterone further increased, whereas those of aldosterone fell below basal levels (the aldosterone-escape phenomenon). The activities of 3HSD and 11OH were enhanced, that of 180H decreased. Therefore, ACTH stimulates zona glomerulosa growth and transforms parenchymal elements into zona fasciculata celltypes. Cyanoketone nullified acute ACTH effects on plasma and intracellular concentrations of corticosterone and aldosterone, but did not affect the activities of 11OH and 18OH. Chronic ACTH treatment produced similar results, although 18OH activity was not suppressed. The mechanism underlying the aldosterone-escape phenomenon may thus involve a rise in the intracellular concentration of corticosterone, caused by the enhanced synthesis and activation of 3HSD and 11OH.  相似文献   

3.
The paper characterizes Darwin's theory, providing a synthesis of recent historical investigations in this area. Darwin's reading of Malthus led him to appreciate the importance of population pressures, and subsequently of natural selection, with the help of the wedge metaphor. But, in itself, natural selection did not furnish an adequate account of the origin of species, for which a principle of divergence was needed. Initially, Darwin attributed this to geographical isolation, but later, following his work on barnacles which underscored the significance of variation, and arising from his work on botanical arithmetic, he supposed that diversity allowed more places to be occupied in a given region. So isolation was not regarded as essential. Large regions with intense competition, and with ample variation spread by blending, would facilitate speciation. The notion of place was different from niche, and it is questioned whether Darwin's views on ecology were as modern as is commonly supposed. Two notions of struggle are found in Darwin's theory; and three notions of variation. Criticisms of his theory led him to emphasize the importance of variation over a range of forms. Hence the theory was populational rather than typological. The theory required a Lamarckian notion of inheritable changes initiated by the environment as a source of variation. Also, Darwin deployed a use/habit theory; and the notion of sexual selection. Selection normally acted at the level of the individual, though kin selection was possible. Group selection was hinted at for man. Darwin's thinking (and also the exposition of his theory) was generally guided by the domestic-organism analogy, which satisfied his methodological requirement of a vera causa principle.  相似文献   

4.
    
Partial and total loss of function mutant alleles of a putative Drosophila homologue (DPhK-) of the vertebrate phosphorylase kinase -subunit gene have been isolated. DPhK- is required in early embryonic processes, such as gastrulation and mesoderm formation; however, defects in these processes are seen only when both the maternal and zygotic components of DPhK- expression are eliminated. Loss of zygotic expression alone does not appear to affect normal embryonic and larval development; some pupal lethality is observed but the majority of mutant animals eclose as adults. Many of these adults show defects in their leg musculature (e.g. missing and degenerating muscles), in addition to exhibiting melanised tumours on their leg joints. Loss of only the maternal component has no obvious phenotypic consequences. The DPhK gene has been cloned and sequenced. It has an open reading frame (ORF) of 1680 by encoding a 560 amino acid protein. The predicted amino acid sequence of DPhK- has two conserved domains, the catalytic kinase and calmodulin-binding domains, separated by a linker sequence. The amino acid sequence of DPhK- is homologous to that of mammalian PhK- proteins but differs in the length and amino acid composition of its linker sequence. The expression of DPhK- mRNA is developmentally regulated. We discuss the implications of these observations.  相似文献   

5.
Summary This study attempts to elucidate the mechanism through which lysosomal accumulation occurs with age in the epithelial cells of the thyroid gland and especially in the active follicles of the aging mouse thyroid. Thyroid morphology and function in old CBA (at least 24 months of age) male mice were compared with those in young (2 months of age) animals. The effects of different intake of iodine were tested and compared in both cohorts, each of which was divided into three groups: (i) low iodine group, (ii) moderate iodine group, and (iii) high iodine group. As expected, the present work confirmed the well-known accumulation with age of cold follicles coexisting with active follicles in the old mouse thyroid. Attention has been focused on the active follicles whose follicular cells contained in their cytoplasm a large number of pleomorphic dense bodies. The lysosomal nature of these bodies, referred to as secondary lysosomes, was confirmed by histochemistry; however, they displayed variability in acid phosphatase staining. In old animals, regardless of the type of iodine regimen, the ratio between relative follicular volume and relative colloid volume as determined by morphometry remained unchanged. Ultrastructurally, the relative volume occupied by secondary lysosomes in active follicles was always higher than in the young groups. Autoradiographic studies with 125I revealed that a large part of the radioactivity was located in secondary lysosomes of thyroid cells in active follicels of old mice when radioiodine was injected 3 weeks before death. Two different types of vacuoles were present in a non-negligible number of thyrocytes of the active follicles in aged cohorts. The first type was made up of grossly dilated rough endoplasmic cisternae, the second corresponded to intracytoplasmic microfollicular vacuoles. Both aspects have been described in conditions of chronic stimulation. It is concluded (1) that different intake of iodine for 6 weeks does not modulate the thyroid morphology in old mice; (2) that in the thyrocytes of the active follicles in old mice accumulation of secondary lysosomes occurs due to a slowdown of turnover; and (3) that the follicular cells of active follicles feature morphological aspects suggesting a hyperactive state compensating the lack of hormone production in the cold follicles.  相似文献   

6.
In the present report, we used serological, cellular, and restriction fragment length polymorphism (RFLP) to investigate the DR1 haplotype in the Israeli population. We describe an Israeli homozygous typing cell (HTC), HLA-DwLVA, which defines a new lymphocyte-activating determinant associated with Bw65, DR1 and distinct from Dwl. The parents of this donor, non-Ashkenazi Algerian Jews, are first cousins and share HLA-Cw8, Bw65, BfS, DR1, DQw1, DPw4. No specificity could be assigned to HLA-DwLVA using the 91 Ninth Workshop HTCs. Two families and forty unrelated DR1 individuals were studied with DwLVA and a panel of DR1/Dw1 HTCs. HLA-DwLVA showed segregation as a single determinant within families. This new specificity was present in 24 out of 40 (60%) unrelated DR1 individuals, indicating that in the Israeli population DwLVA is the main lymphocyte-defined determinant associated with the serologically defined DRI specificity, in contrast to non-Jewish Caucasoids where DR1 is significantly associated with Dw1. The vast majority of DwLVA-positive carriers were also Bw65 carriers, indicating that Bw65, DR1, DwLVA may represent a typical allele combination in the Israeli population. The RFLP analysis established the correlation of certain RFLPs with Dw1 and DwLVA. In addition, we describe a cluster of RFLPs that may correspond to a new Dw subtype associated with DR1, for which no serological and cellular reagents have been described so far.  相似文献   

7.
Mattres  Dieter 《Zoomorphology》1962,51(4):375-546
Ohne ZusammenfassungAlphabetisches Verzeichnis der im Text gebranchten Abkürzungen AK Anbieten der Kopfgrube () - AR-seitig außenrandseitig (auf Elytre bezogen) - EO Elytralorgan (EO-Arten = Arten mit Elytralorganen im männlichen Geschlecht) - f Flucht () - F Flucht () - FA, fa frontale Auseinandersetzung (, ) - FS, fs Fühlertrillern bzw. Frontalspiel (, ) - gk Grubenknabbern () - IR-seitig innenrandseitig (auf Elytre bezogen) - K Kopulation - KG Kopfgrube (KG-Arten = Arten mit Kopfgrube im männlichen Geschlecht) - KI Abdomenkitzeln () - KV Kopulationsversuch () - LP-Feld den weiblichen Labialpalpen korreliertes Drüsenporenfeld - MP-Feld den weiblichen Maxillarpalpen korreliertes Drüsenporenfeld - 180 Drehung des um 180° - ob Organbeißen () - ok Organknabbern () - OZ Organzuwendung () - P Prüfung der Kopulationsbereitschaft durch - RB rückwärtige Berührung durch - SLV Seitwärtslauf nach vorn () - SLH Seitwärtslauf nach hinten () - U Umrundung () - vl Vorwärtslauf () - 180 Drehung des um 180° Habilitationsschrift.  相似文献   

8.
The primary structure of Rose-ringed Parakeet hemoglobin -chain was established, completing the analysis of this hemoglobin. Comparisons with other avian -chains show variations smaller than those for the corresponding -chains. There are 11 amino acid exchanges in relationship to the only other characterized psittaciform -chain, and a total of 35 positions are affected by differences among all avian -chains analyzed (versus 61 for the -chains). At three positions, the Psittacula -chain has residues unique to this species. Three 11 contacts are modified, by substitutions at positions 51, 116, and 125.  相似文献   

9.
It is shown that the utility of usual circular line source models is highly questionable. A line source model related to arbitrary cross-sections is given and essential differences between the source strength of the circular and non-circular model are found in the case of fairly flat elliptic fibers.  相似文献   

10.
Rapid multiplication of axillary meristems and direct shoot development occurred from nodal explants of mature Eucalyptus tereticornis Sm. with 5.3 M NAA, 1.1 M IAA and 4.4 M BA in Murashige-Skoog medium. Repeated subcultures of the second generation shoot cultures into low cytokinin-auxin containing media (0.44–0.88 M BA+0.1 M NAA) yielded axillary microshoots in large numbers. Half-strength MS liquid medium with 4.9 M IBA, 5.5 M IAA and 5.3 M NAA for four days, half-strength semi-solid hormonefree MS medium with charcoal, and MS liquid medium without charcoal and hormones, in sequence, induced rooting of shoots in the dark. This system is suitable for the mass propagation of this difficult-to-root eucalypt.Abbreviations BA 6-benzyladenine - IAA indole-3-acetic acid - IBA -indole-3-butyric acid - 2-iP isopentyl adenine - Kn kinetin - MS Murashige-Skoog - NAA -naphthalene acetic acid - PVP polyvinylpyrrolidone  相似文献   

11.
A nonstationary interaction, that controls DNA replication and the cell cycle, is derived from a manybody physics model in a chemically open T cell. The model predicts a long range force F()=-(/2) (1-)(2-) between the pre-replication complexes (pre-RCs) bound by DNA, =/N being the relative displacement of preRCs, the number of pre-RCs, N the threshold for initiation, and the compressibility modulus in thelattice of pre-RCs which behaves like an elastically braced string. Initiation of DNA replication is induced by a switch of sign of F(), from attraction (-)and assembly in the G 1 phase (0 < < N), to repulsion (+) and partialdisassembly in the S phase (N < < 2N), with release of licensing factors from the pre-RCs, thus explaining prevention of re-replication. Replication is terminated by a switch of sign of F at = 2N, when all primed replicons are duplicated once, and F(0)=0 corresponds to a resting cell in absence of driving force at = 0. The switch of sign of force at = N also explains the dynamic instability in growing microtubules (MTs), as well as switch in the interleukin-2 (IL2) interaction with its receptor in late G 1, at the restriction point. Shape, slope and scale of the response curves derived agree well with experimental data from dividing T cells and polymerizing MTs, the variable length of which is due to anonlinear dependence of the growth amplitude on the initial concentrations of tubulin dimers and guanosine-tri-phosphate (GTP).  相似文献   

12.
Zusammenfassung Die intravitale Karyorrhexig wird am exokrinen Pankreas der Maus nach Osmium- und Formalinfixierung licht- und elektronenmikroskopisch untersucht. Im Verlaufe der Karyorrhexis kommt es zu einer Trennung des Karyoplasmas in 'Chromatin und 'Karyolymphe (Interchromatin-Substanz). In fortgeschrittenen Stadien ist das Bild solcher Zellkerne — im Gegensatz zu normalen Intermitosekernen — nach beiden Fixierungsmethoden fast identisch. Das Chromatin ist in dichten, membranständigen Kappen konzentriert. Der übrige Kernraum wird — abgesehen vom Nukleolus — von der hellen Karyolymphe ausgefüllt. In ihrem Bereich treten die sog. Interchromatingranula (200–250 Å), einzeln oder in dichten Haufen, meist deutlich hervor. Der Nukleolus, dessen Feinstruktur nicht auffallend verändert ist, liegt entweder frei oder den Chromatinkappen unmittelbar an. Die Kernhülle ist bei fortgeschrittener Karyoplasmaentmischung unversehrt oder über kürzere oder längere Strecken geschwunden. Im Endstadium der Karyorrhexis sind mehrere, von Kernmembranfragmenten unvollständig begrenzte Chromatinbrocken wahllos im Zelleib verstreut. Die cytoplasmatischen Strukturen können auch bei ausgeprägten Kernveränderungen noch weitgehend normal aussehen.Die karyorrhektischen Kernveränderungen werden als Folge einer 'Entmischung des Karyoplasmas gedeutet, für die eine Dehydratation der DNS-tragenden Chromosomenstrukturen verantwortlich gemacht wird. Auch das Sichtbarwerden und das Verklumpen der 'Interchromatingranula wird auf eine Dehydratation zurückgeführt.
Summary The intravital caryorrhexis in the exocrine pancreas of the mouse was studied by means of light- and electron microscopy after fixation with osmium and formaldehyde. During caryorrhexis the caryoplasm segregates into chromatin and caryolymphe (interchromatinic substance). In contrast to normal intermitotic nuclei both fixations result in a very similar picture of the typical caryorrhectic nuclei. The chromatin is concentrated in dense caps associated with the nuclear envelope. Except those dense caps and apart from the nucleolus the whole nucleus is occupied by the light caryolymphe. In this area the so-called interchromatinic granules (200–250 Å) become clearly visible, isolated or in dense clumps. The nucleolus, the fine structure of which has not remarkably changed, can be found either isolated or in touch with the chromatin caps. During advanced segregation of the caryoplasm the nuclear envelope was found to be either unimpaired or had disappeared for variable lenghths. In the final stage of caryorrhexis several chromatin clumps — partly confined by fragments of the nuclear envelope — are distributed irregularly within the cell. Even in the case of pronounced nuclear changes the cytoplasmic structures may appear almost unaffected.It is assumed that the nuclear changes during caryorrhexis are due to a segregation of the caryoplasm, caused by dehydration of the DNA-carrying chromosome fibrils. Also dehydration is made responsible for the appearance and clumping of the interchromatinic granules.
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13.
Summary The slow reassociating fraction of mouse DNA (unique DNA), when allowed to reassociate in 0.14 m sodium phosphate buffer at 50 °C showed a biphasic melting curve with a transition at 78–80 °C. On the basis of this feature, the slow reassociating DNA was separated preparatively into two fractions: unique DNA I and II. Their duplexes showed differences with respect to thermal stability, S1 nuclease resistance and rate of reassociation. About one third of the sequences in each fraction were fraction-specific. The conclusion was drawn that for unique DNA I these should be the low repetitive or single copy related sequences (multigene families) and for unique DNA II—the unrelated single copy sequences or recent families of low repetitive not yet diverged sequences.  相似文献   

14.
Apostichopus (= Stichopus) japonicus blastulae and gastrulae were acclimated for 18 h to salinities of 32 (control), 24 and 22 (the lower limit of the range of tolerance), and 20 (below the range of tolerance). Acclimation to 20 resulted in the appearance of teratic larvae, most of which subsequently died. Acclimation to 24, 22, and 20 led to a shift in the range of tolerance of the larvae at further stages of development. With a decrease in salinity, acclimated larvae developed more successfully than unacclimated larvae. Acclimated larvae attained the pentactula stage and settled at a salinity range of 32–20; unacclimated larvae, at 32–22. At different stages of development, acclimated larvae survived greater decreases in salinity than unacclimated larvae. The acclimation effects could be traced up to metamorphosis and settling, i.e., two weeks after the end of the acclimation process.  相似文献   

15.
The conformational properties of the oligosaccharide chain of GM1 ganglioside containingN-glycolyl-neuraminic acid, -Gal-(1-3)--GalNAc-(1-4)-[-Neu5Gc-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer, were studied through NMR nuclear Overhauser effect investigations on the monomeric ganglioside in dimethylsulfoxide, and on mixed micelles of ganglioside and dodecylphosphocholine in water. Several interresidual contacts for the trisaccharide core--GalNAc-(1-4)-[-Neu5Gc-(2-3)]--Gal-were found to fix the relative orientitation of the three saccharides, while the glycosidic linkage of the terminal -Gal-was found to be quite mobile as the -Gal-(1-3)--GalNAc-disaccharide exists in different conformations. These results are similar to those found for two GM1 gangliosides containingN-acetyl-neuraminic acid and neuraminic acid [1].Abbreviations Ganglioside nomenclature is in accordance with Svennerholm [23] and the IUPAC-IUB Recommendations [24] GM3(Neu5Ac) II3Neu5AcLacCer, -Neu5Ac-(2-3)--Gal-(1-4)--Glc-(1-1)-Cer - GM3(Neu5Gc) II3Neu5GcLacCer, -Neu5Gc-(2-3)--Gal-(1-4)--Glc-(1-1)-Cer - GM1(Neu5Ac) II3Neu5AcGgOse4Cer, -Gal-(1-3)--GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - GM1(Neu5Gc) II3Neu5GcGgOse4Cer, -Gal-(1-3)--GalNAc-(1-4)-[-Neu5Gc-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - GM1(Neu) II3NeuGgOse4Cer, -Gal-(1-3)--GalNAc-(1-4)-[-Neu-(2-3)]--Glc-(1-1)-Cer - GD1a IV3Neu5AcII3Neu5AcGgOse4Cer, -Neu5Ac-(2-3)--Gal-(1-3)--GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - GalNAc-GD1a IV4GalNAcIV3Neu5AcII3Neu5AcGgOse4Cer, -GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-3)--GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - Neu neuraminic acid - Neu5Ac N-acetyl-neuraminic acid - Neu5Gc N-glycolyl-neuraminic acid - Cer ceramide  相似文献   

16.
Culture filtrates of 19 of 21 (90%) -hemolytic isolates ofAeromonas hydrophila caused fluid accumulation in permanently ligated rabbit ileal loops, whereas no fluid was accumulated with filtrates of eight non--hemolytic isolates. Antiserum to purified -hemolysin neutralized the ileal loop activity of culture filtrates from four of four -hemolytic isolates, and treatment at 56°C for 10 min eliminated the loop activity of six additional isolates. These results support the conclusion that -hemolysin alone causes significant changes in intestinal permeability and that it is a more common pathogenic mechanism than the heat-stable cytotonic enterotoxin. Electrophoretic and serological assays showed evidence for production of only one species of -hemolysin byA. hydrophila.  相似文献   

17.
We have developed a new method for the large scale preparation of pyridylaminated (PA-) oligosaccharides from glycoproteins. Phenol/chloroform extration was adapted for the removal of protein and excess 2-aminopyridine, improving the efficiency of preparation. From a 2.5 g sample of human apo-transferrin, 25–30 mol of agalacto biantennary PA-oligosaccharide could be obtained. By increasing the concentration of PA-oligosaccharide substrate, we were able to detect a very low level ofN-acetylglucosaminlytransferase IV activity in CHO cell extracts.Abbreviations PA 2-aminopyridine - SDS sodium dodecyl sulfate - GlcNAc N-acetylglucosamine - GnT N-acetylglucosaminyltransferase - Gn,Gn-bi-PA GlcNAc1-2Man1-3(GlcNAc1-2Man1-6)Man1-4GlcNAc1-4GlcNAc-2-aminopyridine - Gn,Gn,Gn-tri-PA GlcNAc1-2(GlcNAc1-4)Man1-3(GlcNAc1-2Man1-6)Man1-4GlcNAc1-4GlcNAc-2-aminopyridine - Gn,Gn,Gn-trí-PA GlcNAc1-2Man1-3({GlcNAc1-2(GlcNAc1-6)Man1-6})Man1-4GlcNac1-4GlcNAc-2-aminopyridine - Gn,(Gn),Gn-bi-PA GlcNAc1-2Man1-3(GlcNAc1-4)(GlcNAc1-2Man1-6)Man1-4GlcNAc1-4GlcNAc-2-aminopyridine  相似文献   

18.
The secondary plant compound 2,5-Dihydroxymethyl-3,4-dihydroxypyrrolidine (DMDP), an analogue of -D-fructofuranose, is lethal to the larvae of the bruchid beetle Callosobruchus maculatus F. when incorporated into artificial diets at levels greater than 0.03%. In the range 0.003% to 0.03% the compound reduces larval survival in a dose-dependent manner. The -D-glucosidase digestive enzyme demonstrated in homogenates of the alimentary tract of the larvae is strongly inhibited by the compound in a competitive manner.
Résumé La substance secondaire 2,5-dihydroxyméthyl-3,4-dihydroxypyrrolidine (DMDP), analogue du -fructofuranose, est létale pour les larves de C. maculatus lorsqu'elle est incorporée dans des régimes alimentaires à des taux supérieurs à 0.03%. Entre 0.003% et 0.03%, la substance réduit la survie larvaire proportionnellement à la dose. L'enzyme digestive -D-glucosidase observée dans les homogénats du tube digestif de la larve est fortement inhibée par la substance d'une façon compétitive.
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19.
Residual toxicities of registered and selected experimental pesticides used on citrus against Agistemus industani Gonzalez (Acari: Stigmaeidae) were compared. Pesticides considered highly toxic to A. industani were: abamectin 0.15 EC at 731ml/ha+FC 435-66 petroleum oil at 46.8l/ha, pyridaben 75WP at 469g/ha, ethion 4EC at 7.01l/ha+FC 435-66 petroleum oil at 46.8l/ha, propargite 6.55 EC at 3.51l/ha, chlorfenapyr 2SC at 1.46l/ha applied alone or in combination with FC 435-66 petroleum oil at 46.8l/ha, sulphur 80DF at 16.81kg/ha, dicofol 4EC at 7.01l/ha, fenbutatin oxide 50WP at 2.24kg/ha, benomyl 50WP at 2.24kg/ha, benomyl 50WP at 1.68kg/ha+ferbam 76 GF at 5.60kg/ha, ferbam 76GF at 11.21kg/ha, neem oil 90EC at 46.8l/ha, and copper hydroxide DF (40% metallic copper) at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha. Pesticides that were moderately to slightly toxic included: copper sulphate 98% at 4.48kg metallic copper/ha+FC 435-66 petroleum oil at 46.8l/ha, fenbuconazole 2F at 280ml/ha+FC 435-66 petroleum oil at 46.8l/ha, FC 435-66 petroleum oil applied alone at 46.8l/ha or 23.4l/ha, and diflubenzuron 25WP at 1.40kg/ha. Pesticides that were non-toxic included: fenbuconazole 2F at 585ml/ha, malathion 57EC at 5.85l/ha, FC 435-66 petroleum oil at 46.8l/ha, carbaryl 80S at 3.36kg/ha, chlorpyrifos 4EC at 4.68l/ha, and formetanate 92SP at 1.12kg/ha. Understanding the toxic effects of field weathered pesticides against key predacious mite species is important for effective IPM. The results of this study provide a comparison of direct and indirect toxic effects of various pesticides to A. industani under field conditions.  相似文献   

20.
Embryonic, larval, and juvenile development of an Indian cyprinid fish, Chela dadiburjori, is described from laboratory-reared specimens. The eggs, measuring 0.7–0.9mm in diameter, were demersal, almost spherical in shape, transparent and unpigmented, with a pale yellow yolk and no oil globule. Hatching occurred 50–61h after fertilization at ca. 27°C. The newly hatched larvae, measuring 2.4–2.6mm in body length (BL), had melanophores on the body with 14–16+14–17=29–31 myomeres. Two dark transverse bands on the ventral body surface and one melanophore on the lower margin of the eye in newly hatched larvae were diagnostic. Additionally, a cement organ for adhering to objects was present on the forehead of yolk sac larvae <3.1mm BL. The yolk was completely absorbed at 3.5mm BL. Notochord flexion was initiated at 5.0mm BL and finished at 6.0mm BL. Aggregate numbers of all fin rays were completed at 9.2mm BL. Squamation was initiated on the caudal peduncle at 8.0mm BL and completed at 10mm BL. The eggs of C. dadiburjori resembled those of the closely related species Devario malabaricus and Danio rerio. The larvae and juveniles of C. dadiburjori were also similar to those of the latter species in general morphology, especially the presence of body melanophores in newly hatched individuals and a distinctive lateral streak on the head during the period from yolk sac to postflexion larvae. However, early yolk sac larvae of C. dadiburjori were more similar to those of Devario malabaricus than Danio rerio in having a cement organ on the forehead. Larvae and juveniles of C. dadiburjori differed from those of the latter two species in pigmentation on the ventral body surface at hatching and around the mouth during the period from preflexion to early postflexion larvae and in having a dark lateral streak or band on the body in postflexion larvae and juveniles.  相似文献   

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