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1.
TheN-linked carbohydrate chains of the-subunit of highly purified urinary human chorionic gonadotropin have been re-investigated. The oligosaccharides were released enzymatically by peptide-N 4-(N-acetyl--glucosaminyl)asparagine amidase-F, and fractionated by a combination of FPLC and HPLC. As a result of the application of improved fractionation methods, apart from the earlier reported carbohydrate chains, also small amounts of trisialo tri- and tri-antennary oligosaccharides were found. The primary structures of the latter carbohydrate chains have been determined by 500-MHz1H-NMR spectroscopy to beAbbreviations hCG human chorionic gonadotropin - hCG- -subunit - hCG- -subunit - PNGase-F peptide-N 4-(N-acetyl--glucosaminyl)asparagine amidase-F (E.C. 3.5.1.52) - endo-F endo--N-acetylglucosaminidase-F (E.C. 3.2.1.96) - SDS sodium dodecyl sulphate - PAGE polyacrylamide gel electrophoresis - CBB coomassie brilliant blue R 250 - GlcNAc N-acetylglucosamine - NeuAc N-acetylneuraminic acid - Man mannose - Gal galactose - Fuc fucose  相似文献   

2.
Summary The seven possible primary trisomics of Petunia (2 n= 14) located in the progenies of triploid, hypertriploid and hypotriploid plants were distinguished from one another and from diploid on the basis of cytological and morphological criteria. They were provisionally named as Oval, Semi, Slender, Pseudonormal, Arrow, Narrow and Giant. In three of the trisomics, the extra chromosome was identified for the first time at pachytene stage. Postpachytene studies revealed no precise relationship between the length of extra chromosome and the frequency of multiple association.  相似文献   

3.
Summary Five subunits (-, -, -, - and -subunits) of the six -and -subunits) in the F1 portion (F1ATPase) of sweet potato (Ipomoea batatas) mitochondrial adenosine triphosphatase were isolated by an electrophoretic method. The - and -subunits were not distinguishable immunologically but showed completely different tryptic peptide maps, indicating that they were different molecular species. In vitro protein synthesis with isolated sweet potato root mitochondria produced only the -subunit when analyzed with anti-sweet potato F1ATPase antibody reacting with all the subunits except the -subunit. Sweet potato root poly(A)+RNA directed the synthesis of six polypeptides which were immunoprecipitated by the antibody: two of them immunologically related to the -subunit and the others to the - and -subunits. We conclude that the -subunit of the F1ATPase is synthesized only in the mitochondria and the -, - and -subunits are in the cytoplasm.  相似文献   

4.
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   

5.
Conditions which induce a transmembrane electrical potential, positive with respect to the inside of membrane vesicles, result in a substantial (4–12-fold) stimulation of the activity of membrane-associated -glucan synthetases in a membrane preparation derived from the developing cotton (Gossypium hirsutum L.) fiber. Induction of electrical potentials which are negative with respect to the inside of the membrane vesicle results in little or no stimulation of -glucan synthesis. Those products whose synthesis is stimulated are mainly -1,3-glucan, but there is also a considerable increase in -1,4-glucan. No -1,4-glucan (starch) was detected in the reaction products. A transmembrane pH gradient was found to have no effect on -glucan synthesis. The results indicate that a transmembrane electrical potential can influence, either directly or indirectly, the activity of membrane-associated polysaccharide synthetases.Abbreviations UDP-glucose uridine-5-diphosphoglucose - PEG polyethylene glycol - BTP bistrispropane (1,3-bis[tris(hydroxymethyl)methylamino]propane) - MES 2(N-morpholino)ethanesulfonic acid - VAL valinomycin  相似文献   

6.
Summary The temporal muscles of the guinea pig show a sexual differentiation reflected in their histochemical enzyme pattern. Using histochemical methods for mitochondrial (SDH, -GPDH), and glycolytic enzymes (phosphorylase, LDH) it could be shown, that in adult animals the male muscle is a white muscle with marked activity of glycolytic enzymes, the female muscle a red muscle displaying high activity of mitochondrial enzymes. This differential enzyme pattern can be converted by the application of testosterone to the female type during the postnatal development. The male sex hormone thus affects the histochemical enzyme pattern of the muscle, converting the red, female into a white, male muscle in the female guinea pig.  相似文献   

7.
Zusammenfassung Das Zetern der Amseln wurde von 1969 bis 1972 in einem sehr regelmäßig besetzten Revier automatisch registriert. Sowohl das Zetern sämtlicher registrierter Amseln, als auch das Zetern bestimmter Individuen gehorchen den meisten Aschoff'schen Regeln. Zwischen Individuen sind die Zeteranfänge äußerst unterschiedlich, die Zeterenden dagegen nicht. Die individuellen Zeteranfänge reichen in der Vergleichszeit von ca. 50 min bis 20 min vor Sonnenaufgang (Mittelwerte für 1/3 Monat).
The alarm-call activity of the Blackbird
Summary In a very regulary occupied district the alarm-call (Zetern) of blackbirds was automatically recorded from 1969 till 1972. The Zetern of all recorded blackbirds as well as the Zetern of single individuals obey to most of Aschoff's rules. Among the individuals the beginnings of the Zetern are extremly different, but not the endings of the Zetern.The interindividual beginnings of Zetern in the comparable time reach from about 50 min. to about 20 min. before sunrise (mean values for 1/3 of a month).
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8.
A -amylase (EC 3.2.1.2) was identified in the outer pericarp (P) of developing seeds of wheat (Triticum aestivum L.) and compared with the well known -amylase which is synthesized during seed development in the starchy endosperm (E). The enzyme P already exists in the tissues before anthesis and vanishes at the time when E starts to accumulate. The isoelectric-focusing patterns of P and E are very similar. The relative molecular weight (Mr) of P is slightly higher than that of E (66 and 64.5 kDa, respectively). Both P and E exhibit common epitopes in addition to epitopes specific for each of them. The two enzymes were identified in small amounts in the green tissues of the developing seeds (inner pericarp and testa). No antigenic difference was detected between P and the -amylases of roots and leaves.Abbreviations P pericarp -amylase - E endosperm -amylase - IS1 anti--amylase immune serum - IS2 anti- and anti- amylase immune serum - IS3 anti- amylase immune serum - IEF isoelectric focusing - IgG immunoglobulin G The authors thank Dr. P. Ziegler (Universität Bayreuth, FRG) for stimulating discussion and for useful suggestions during the writing of the text. The authors thank Miss C. Mayer for her skillful technical assistance.  相似文献   

9.
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   

10.
Starting from the conceptual premises of Garrod, who as long ago as 1902 spoke of chemical individuality, and of Burnet (1949), who recognized as self one's own molecular antigenic structures (as opposed to the antigenic alien: the non- self), the discovery and understanding of HLA antigens and of their extraordinarily individual and differentiated polymorphisms have gained universal recognition. Transplant medicine has now dramatically stressed, within man's knowledge of himself, the characteristic of his biological uniqueness. Today man, having become aware of being a biological antigenic-molecular individuality which is unique and different from that of all of his fellow men (except for monozygotic twins), can therefore easily consider himself a true biological Ego.Abbreviations BMT bone marrow transplantation - GVHD graft versus host disease - HLA human leukocyte antigens - MHC major histocompatibility complex - MLC mixed lymphocyte culture - MLR mixed lymphocyte reaction  相似文献   

11.
The karyotypes of three taxa from thePhleum alpinum group of sect.Phleum (P. alpinum subsp.rhaeticum, 2n = 14,P. commutatum, 2n = 28, and informally namedP. commutatum, 2n = 14) were investigated by Giemsa C-banding. The overall similarity of diploid genomes suggests thatP. alpinum subsp.rhaeticum andP. commutatum are closely related — their karyotypes vary only with respect to their average amounts of telomeric heterochromatin. TheP. commutatum genome contains less telomeric heterochromatin than the genome ofP. alpinum subsp.rhaeticum, but in theP. alpinum group as a whole almost fluent transition between low (1.5%) and high (25.5%) amounts of telomeric heterochromatin was observed among populations. In the karyotype of tetraploidP. commutatum, seven distinguishable chromosome types were observed. Each of them is represented at somatic metaphase by four chromosomes. C-band structure of karyotype and average amount of telomeric heterochromatin suggest that this taxon has originated from hybridization between two related diploid forms of theP. commutatum — P. alpinum complex.  相似文献   

12.
Summary The functional R6K origin is composed of two DNA elements, one of 580 bp carrying the origin sequences and the other of 277 bp containing the seven 22 bp direct repeats previosly identified as also required for and origin activity. These two genetic elements are separated by approximately 3,000 bp of R6K sequences which are dispensable for origin activity. The function of the origin depends on the presence in cis of the 580 bp and the 277 bp fragments and requires that they be oriented as in the intact R6K. Activation of the origin depends on the R6K replication initiation protein .Within the 580 bp of the origin, there is a sequence of 98 bp which appears as an inverted repeat of 96 bp in the replicon. Deletion of the 96 bp or 98 bp results in inactivation of the and the origins respectively. These long repeats are palindromic and it is suggested that these may serve as the recognition signals for initiation of DNA replication in the and the origins of R6K. DNA homology analysis performed on , and origin sequences, also reveals 10–23 bp sequences in the and the origins that are related to the family of 22 bp direct repeats in the origin which were shown previously to be binding sites for the protein.  相似文献   

13.
The Chassahowitzka, Homosassa and Crystal rivers along the central Gulf coast of Florida were studied from 1998 to 2000 to identify factors controlling the abundance and distribution of submersed aquatic vegetation (SAV). Each of these three low-lying coastal rivers are spring-fed and exhibit low to moderate absolute flow rates (flows in either direction because of tidal influences, 0.06–0.46ms–1) with only 14 of the stations sampled for SAV having flow rates in excess of 0.25ms–1. At those stations where flow rates exceeded 0.25ms–1, the substrate was generally comprised of exposed limestone outcroppings and did not provide a favorable habitat for either submersed macrophytes or macroalgae. The remaining sampling stations, where flow rates were less than 0.25ms–1, had suitable substrates (e.g. mud, mud/sand, and sand) for the colonization and subsequent growth of SAV. Light availability and salinity were determined to be major factors affecting the distribution and abundance of SAV. Sampling stations, where the percent of incident light at the surface reaching the substrate was less than 10, had little or no SAV biomass. Low SAV biomass was also linked to sites where annual average salinities exceeded 3.5. Nutrient loads and nutrient concentrations accounted for little variance in SAV biomass after accounting for flow and related substrate type, light and salinity. These latter factors control the distribution and abundance of SAV in these three Florida coastal rivers.  相似文献   

14.
T. M. Butt  A. Beckett 《Protoplasma》1984,120(1-2):61-71
Summary A detailed account of the ultrastructure and behaviour of the spindle pole body (SPB) of the entomophthoraceous fungusErynia neoaphidis is presented for the first time.The SPB consists of extranuclear (ENC) and intranuclear (INC) components. The ENC is a saucepan-shaped structure which lies in a pocket of the nuclear envelope. It is composed of a forked, fibrillar handle and a shallow, cylindrical pan. The pan has a wall of two layers, both of which are thickened with a regular periodicity so that they appear to be beaded. It is postulated that the pan is formed from rough endoplasmic reticulum and that it synthesizes the amorphous, electron-dense material coating the ENC.The INC is a saucer-shaped, electron-dense plaque in which the ends of the spindle microtubules terminate. During metaphase, a clear zone separates the INC from the nuclear envelope and persists until telophase. The roles of the amorphous, electron-dense material and the clear zone as well as the method of SPB replication are discussed.  相似文献   

15.
The major cytokinins in stems of decapitated, disbudded bean plants have been identified by enzymic degradation, Sephadex LH20 and reversed phase high performance liquid chromatography, and by combined gas chromatography-mass spectrometry as 6-(4-hydroxy-3-methylbut-trans-2-enylamino)-9--D-ribofuranosylpurine (zeatin riboside), 6-(4-hydroxy-3-methylbutylamino)-9--D-ribofuranosylpurine (dihydrozeatin riboside), and the 5-phosphates of these compounds (zeatin ribotide and dihydrozeatin ribotide). Minor cytokinins in this tissue were tentatively identified as dihydrozeatin-O--D-glucoside and zeatin ribotide-O--D-glucoside. [8-14C-]Dihydrozeatin appeared to be rapidly metabolized to dihydrozeatin ribotide when supplied to segments of stems from decapitated plants. These results are discussed in relation to the metabolism and distribution of cytokinins in the whole plant.Abbreviations TEAB triethyl ammonium bicarbonate - UV ultra-violet - GCMS gas chromatography-mass spectrometry - HPLC high performance liquid chromatography - TMS trimethyl silyl  相似文献   

16.
At the end of summer, males of Polistes gallicusfly in swarms around vertical landmarks and land in clusters on their favorite perches, where they drag their legs and abdomen. Here males occasionally crowd around a perched female; they make no effort to defend an exclusive mating territory but instead attempt to copulate by displacing rivals from the female. In this work we describe this spatial-nuptial system, which entails site fidelity without territoriality, unisexual swarms, common patrol routes, collective sexual approaches, and scramble competition polygyny. Mating success is evaluated in relation to the familiarity with flight paths (routine patrollers versus newcomers), to the type of sexual approach (single males versus in- group males), and, in the laboratory, to the individual activity level.  相似文献   

17.
A contextualizing image (CI) is a powerful central image of a dream which appears to contextualize (provide a picture-context for) the dreamer's emotion. For instance, dreamers who have experienced any serious traumatic event sometimes dream, I was overwhelmed by a tidal wave. This appears to picture their feeling of terror and/or vulnerability.A scoring system for CIs is examined here and is applied to dreams and daydreams supplied by 40 students. Two raters scoring dreams on a blind basis showed good inter-rater reliability. Recent dreams were shown to have more as well as more intense CIs than recent daydreams; likewise, dreams that stand out had more intense CIs than daydreams that stand out. Students with thin boundaries had more and more intense CIs than students with thick boundaries in their recent dreams and nightmare, but not so clearly in dreams and nightmares that stand out. The emotions judged as contextualized by the powerful images tended towards fear/terror and helplessness/vulnerability in dreams (especially in dreams that stand out) whereas emotions contextualized by images in daydreams showed a wide range with no clusters.  相似文献   

18.
Summary The total pigment and astaxanthin content ofPhaffia rhodozyma increased with increasing concentrations -pinene up to 500 l -pinene/l. Above this concentration the total pigment and astaxanthin content as well as the biomass production decreased. The addition of 500 l -pinene/l increased the total pigment content from 1652 g/g to 2201 g/g and the astaxanthin content from 1554 g/g to 1883 g/g. A sharp decrease in maximum specific growth rate occurred above 150 l -pinene/l.  相似文献   

19.
Summary Isoelectric focusing of extracts from the endosperm of mature grains of hexaploid wheat and related species was used to study the genetic control of Iodine binding factor (IBF). Ten IBF bands were present in Chinese Spring (CS) and analysis of the nullisomictetrasomic and ditelosomic lines of CS showed nine of them to be controlled by genes on the long arms of the homoeologous group 5 chromosomes. Five alleles were detected at Ibf-A1 locus, four at Ibf-B1 and four at Ibf-D1 among a sample of 46 wheat genotypes. Homoeoloci were found on chromosome 5R of Secale cereale, 5E of Agropyron elongatum, 5U of Aegilops umbellulata, 5Agi of Agropyron intermedium, 5S1 and 4S1 of Aegilops sharonensis and 4H of Hordeum vulgare.  相似文献   

20.
Hybridizations ofElymus nutans andE. jacquemontii were carried out with one species ofPseudoroegneria (S genome), and 20Elymus species, each containing either of the SH, SY, SYH, or SYW genomes. Chromosome configurations were analysed at metaphase I of the two target taxa and their interspecific hybrids. It is concluded that (i)E. nutans is an allohexaploid containing the SYH genomes, andE. jacquemontii is an allotetraploid having the SY genomes; (ii) the genomic affinity is associated with the geographic distance between the species studied; (iii) minor genomic structural rearrangements have occurred within the hexaploid taxon ofE. nutans.  相似文献   

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