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1.
Zusammenfassung Vorliegende Arbeit ist eine Weiterführung derLorenz'schen Bewegungsstudien an Anatinen aus dem Jahre 1941, fortgesetzt an Mischlingen zwischen den dort beschriebenen Arten. Die sich dabei ergebenden Befunde machten eine erneute Untersuchung der Elternarten notwendig. Außerdem wurden einige Arten beobachtet, deren Verhalten noch nicht untersucht worden war. Fragestellung und Begründung werden in der Einleitung gegeben.Im zweiten Abschnitt werden einige der vonLorenz gemachten Beobachtungen berichtigt. So zeigten einige der Kreuzungen mitbahamensis, daß die vonLorenz bei eben dieser Art als Kurzhoch-werden bezeichnete Bewegungsweise dem Ab-auf anderer Schwimmenten homolog ist. Ebenso ist die eine der beiden vonLorenz als Kurzhoch-werden bezeichneten Verhaltensweisen des Krickerpels als Ab-auf zu deuten. Der Gruß desflavirostre-Erpels wurde auch bei weiblichen Tieren gesehen. BeiAnas acuta wurde ein Kinnheben festgestellt, das sich in der Form stark vom Kinnheben beiplatyrhynchos unterscheidet. Als neue Verhaltensweisen wurden u. a. das Haltungannehmen und das Tendieren beimflavirostre-Erpel beschrieben.Im dritten Abschnitt werden einige Verhaltensweisen und ihre Funktion diskutiert und der Versuch gemacht, eine Motivationsanalyse zu geben.(Zeichnungen vonHermann Kacher)  相似文献   

2.
An aqueous two-phase system based on the two polymers poly(ethylene glycol) and dextran has been used for the fractionation of cellulase enzymes present in culture liquid obtained by fermentation with Trichoderma reesei. The activities of -glucosidase and glucanases were separated to high degree by using the two-phase systems for a counter-current distribution process in nine transfer steps. While the glucanases had high affinity to the poly(ethylene glycol) rich top phase the -glucosidase was enriched in the dextran-containing bottom phase. Multiple counter-current distribution performed indicates the heterogeneity of -glucosidase activities assuming at least four isoenzyme forms. One step concentration of -glucosidase by using system with 46:1 phase volume ratio resulted in 16 times higher enzyme activity.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

3.
180 rainbow trouts (Salmo gairdneriRich.), aged from 1 to 3 years, were examined for fluctuations, caused by age and season, by means of colour index (CI), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC).CI and MCH behave similarly. Both are increasing until the 2nd year and stay relatively constant thereafter. If the gender is not considered — there are no significant differences in the values of males and females — the CI increases from 1,4 in the first year over 1,6 to 1,7 in the age of 3 years, and the MCH increases from 44,4 over 52,6 , 56,8 , 58,1 to 55,5 .A seasonal periodicity of both indices could not be indicated on not-matured animals (F2) which were two summers of age. Only, the january values appeared increased — CI: 2, MCH: 68,3 — otherwise the CI varies between 1,8 and 1,7 and the MCH between 53,3 and 59,1 .The MCHC-values of the age groups examined vary between 24,4% and 27,3%. The values of the yearlings form an exception (19,8%). These values certainly are inexact and too low because of the small number of individuals checked (3).

Mit finanzieller Unterstützung durch die DFG.Institut für Siedlungswasserbau und Wassergütewirtschaft der Universitat Stuttgart Fischtoxikologische Arbeitsgruppe  相似文献   

4.
Huang  Chuanshu  Zhang  Qunwei  Li  Jingxia  Shi  Xianglin  Castranova  Vincent  Ju  Gong  Costa  Max  Dong  Zigang 《Molecular and cellular biochemistry》2001,222(1-2):141-147
Cadmium is a potent and effective carcinogen in rodents and has recently been accepted by IARC (International Agency for Research on Cancer) as a category 1 carcinogen. Cadmium-induced upregulation of intracellular signaling pathways leading to increased mitogenesis is thought to be a major mechanism for the carcinogenic activity following chronic cadmium exposure. In the present study, we found that exposure of cells to cadmium induced significant activation of AP1 and all three members of the MAP kinase family in mouse epidermal JB6 cells. The induction of AP1 activity by cadmium appears to involve activation of Erks, since the induction of AP1 activity by cadmium was blocked by pretreatment of cells with PD98058. Interestingly, the induction of AP1 by cadmium was greatly enhanced by the chemical tumor promoter, TPA and the growth factor EGF, but not by ultraviolet C radiation. In vivo studies demonstrated that cadmium could also induce transactivation of AP1 in AP1luciferase report transgenic mice. Considering the role of AP1 activation in tumor promotion, the results presented in this study provide a possible molecular mechanism for cadmiuminduced carcinogenesis.  相似文献   

5.
Aspects of the life history of Labeo cylindricus in Lake Chicamba, a man made hydroelectric dam in central Mozambique were investigated. L. cylindricus was found to be a potadrometic, synchronous spawner concentrating in river mouths prior to migrating up flowing rivers in January to spawn. Length-at-(50%)-maturity was attained at a fork length (FL) of 96mm for males and 98mm for females, both within their first year of life. The adult sex ratio was found to be female dominated at 1 male:1.63 females. Scales were used to age the species, with two growth checks deposited annually. Growth was rapid and was best described by the von Bertalanffy growth model as L t =224.2(1–e-0.66(r+0.03))mm FL. A maximum age of 4 years was observed for L. cylindricus with the largest male and female measuring 210mm FL and 235mm FL, respectively. The rate of natural mortality was estimated to be extremely high at 1.93year-1 using length-converted catch curve analysis and is possibly a response to heavy predation by the introduced piscivore Micropterus salmoides.  相似文献   

6.
In vivo casein phosphorylation was analysed in Xenopus full-grown oocytes arrested in the prophase of the meiotic cell division. The phosphorylation was inhibited by the protein kinase inhibitor (PKI) and also by heparin (3 g/ml; final concentration). casein phosphorylation was increased by spermine (2 mM). Therefore, protein kinase A and casein kinase II are both activein vivo in full-grown oocytes and may be involved in the prophase arrest of meiotic cell division.  相似文献   

7.
Values ofK m were determined for three purified sialyltransferases and the corresponding recombinant enzymes. The enzymes were Gal1-4GlcNAc 2-6sialyltransferase and Gal1-3(4)GlcNAc 2-3sialyltransferase from rat liver; these enzymes are responsible for the attachment of sialic acid to N-linked oligosaccharide chains; and the Gal1-3GalNAc 2-3sialyltransferase from porcine submaxillary gland that is responsible for the attachment of sialic acid to O-linked glycoproteins and glycolipids. A procedure for the large scale expression of active sialyltransferases from recombinant baculovirus-infected insect cells is described. For the liver enzymes values ofK m were determined using rat and human asialo1 acid glycoprotein andN-acetyllactosamine as variable substrates; lacto-N-tetraose was also used with the Gal1-3(4)GlcNAc 2-3sialyltransferase. Antifreeze glycorprotein was used as the macromolecular acceptor for the porcine enzyme. Values forK m were also determined using CMP-NeuAc as the variable substrate.Abbreviations NeuAc N-acetylneuraminic acid - Gal galactose - GlcNAc N-acetylglucosamine Enzymes: Gal1-4GlcNAc 2-6sialyltransferase, EC 2.4.99.1; Gal1-3(4)GlcNAc 2-3sialyltransferase, EC 2.4.99.5; Gal1-3GalNAc 2-3sialyltransferase, EC 2.4.99.4.  相似文献   

8.
Summary The ultrastructure of a fir morphological mutant containing multinucleate cells is described in Schizophyllum commune. The germlings of basidiospores which arose from mating fir with wild-type mycelium were studied in culture by phase contrast microscopy to elucidate behavior of multinucleate cells. Nuclear division appeared synchronous from two nuclei yielding four progeny through six nuclei producing twelve products, beyond which loss of synchrony was indicated. Compensatory nuclear migration into an anucleate cell was presumed during synchronous division of nuclear aggregates in the adjacent cell of an individual germling. The migrant nucleus eventually returned to the cell of origin. However, the return route was not via the central pore of the septum but rather occurred at the juncture of the cross-wall with the germling-periphery. Ultrastructure of a partial septum in fir which could accommodate nuclear passage of this sort is described.  相似文献   

9.
E. Schnepf  E. Pross 《Protoplasma》1976,89(1-2):105-115
Summary The epithelial cells of the septal nectaries ofGasteria andAloe have a second wall layer consisting of numerous irregular wall protuberances along the outer wall. They, thus, are typical transfer cells. The wall protuberances develop a short time before the nectar secretion begins. At this time and during the secretory phase the amount of microtubules is at a minimum. After the secretion phase the protuberances disappear gradually while often callose is formed between them. Simultaneously a third wall layer is deposited which covers the remnants of the second layer. During the first developmental stages the cells contain amyloplasts with changing amounts of starch. In the redifferentiation phase they become chloroplasts with a crystalline prolamellar body and small stacks of thylakoids.  相似文献   

10.
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   

11.
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   

12.
Here we consider the concept of kaluchua (a word adopted from the English culture) in group-living animals developed by Imanishi in the 1950s. He distinguished it from bunka (the Japanese equivalent to the English culture) because he thought that bunka had strong connotations of noble and intellectual human-like activities. Although he did not rigidly define kaluchua, his original concept of kaluchua was much broader than bunka and represented non-hereditary, acquired behavior that was acknowledged socially. However, instead of social life, complex feeding skills have often formed the central topic in the current studies of animal culture. In order to provide evidence that more subtle behavioral variations exist among wild chimpanzee (Pan troglodytes) populations, we directly compared the behaviors of two well-habituated chimpanzee groups, at Bossou and Mahale. During a 2-month stay at Bossou, M.N. (the first author) saw several behavioral patterns that were absent or rare at Mahale. Two of them, mutual genital touch and heel tap were probably customary for mature females and for mature males, respectively. Index to palm and sputter are still open to question. These subtle patterns occurred more often than tool use during the study period, suggesting that rarity is not the main reason for their being ignored. Unlike tool use, some cultural behavioral patterns do not seem to require complex skills or intellectual processes, and sometimes it is hard to explain the existence of such behaviors only in terms of function.  相似文献   

13.
Of 98 strains of moulds, isolated from arctic soils, Mortierella minutissima 01, grew the best on agar plates with limonene vapor. Perillyl alcohol and perillic acid were the main products of limonene biotransformation. Maximal yield of perillyl alcohol (125mgl–1) occurred in medium containing 0.8% substrate, at 15°C, pH 6 and after 4–5 d. Revisions requested 27 October 2004; Revisions received 27 November 2004  相似文献   

14.
The migratory history of Sakhalin taimen, Hucho perryi, was examined in terms of strontium (Sr) and calcium (Ca) uptake in the otolith by using wavelength dispersive X-ray spectrometry on an electron microprobe. Otolioth Sr:Ca ratios of freshwater-reared samples remained consistently at low levels throughout the otolith. The Sr:Ca ratios of samples from Lake Aynskoye of Sakhalin Island showed a low value from the core up to a point of 700–2140µm. Thereafter, the ratios increased sharply and remained at higher levels up to the outermost regions. The difference in Sr:Ca ratio might be the result of the presence of individuals that underwent seawater and freshwater life history phases, probably reflecting the ambient salinity or the seawater–freshwater gradient in Sr concentration. Otolith Sr:Ca ratio analysis revealed downstream migration history in H. perryi.  相似文献   

15.
Limbs of flower buds from Petunia hybrida were investigated for -glucosidase activity with dihydroflavonol-glucosides and 4-methyl-umbelliferyl--D-glucoside as substrates. Dihydroflavonol-glucoside -glucosidase is localized in the cell wall. This activity has an acid pH optimum and is also active toward 4-methyl-umbelliferyl--glucoside. Besides this activity a neutral -glucosidase is present. This activity is soluble and is not active toward dihydroflavonol-glucosides. Using starch gel electrophoresis it was shown that no difference in -glucosidase activity is present between mutants able to convert dihydroflavonols into anthocyanins and mutants accumulating dihydroflavonol-glucosides. It is concluded that -glucosidase activity is not involved in anthocyanin synthesis.Abbreviations 4MU--glc 4-methylumbelliferyl--D-glucopyranoside - dHQ-7-g dihydroquercetin-7-glucoside - dHQ-4-g dihydroquercetin-4-glucoside - dHM-4-g dihydromyricetin-4-glucoside Deceased  相似文献   

16.
Summary The mitochondrial ATPase from a PHO 1 mutant (OLI 2, PHO 1, OLI 4 region on mit DNA of S. cerevisiae) was further examined. A new purification method using Lysolecithin instead of Triton allowed us to solubilize and separate a heterogeneous ATPase population from PHO 1-mitochondria: the major abnormal fraction had extremely low oligomycin-sensitivity (but normal specific immunological reactivity), while a minor normal fraction (representing about 20% of the initial mitochondrial ATPase activity) had high sensitivity and affinity for oligomycin.Moderate urea treatment of PHO 1-mitochondria leads to partial loss of ATPase activity and a concomitant increase of oligomycin-sensitivity, suggesting that a heterogeneous ATPase population exists in situ in the mitochondrial membrane: part of the major abnormal ATPase fraction is selectively inactivated by urea, producing a concomitant enrichment in the initially minor normal ATPase fraction.If the minor normal ATPase fraction is the only one capable of in vivo ATP synthesis, the deficient but oligomycin-sensitive cell growth and oxidative phosphorylation in vitro are readily explained.Further structural studies are under way to ascertain whether the minor normal ATPase fraction is strictly identical to the wild type, in which case PHO 1 is a regulatory gene, or not, in which case PHO 1 is a structural gene.  相似文献   

17.
To develop an effective protocol of gene transfer into glomeruli, an ex vivo gene delivery system using rat mesangial cells (RMC) as a vector was examined. RMC genetically engineered with a retrovirus harboring the Escherichia coli -galactosidase gene was used to estimate the efficacy of gene delivery and the location of the cells within the kidney. The RMC expressing -galactosidase, RMCLZ1, was cultured in vitro and the cells were injected into the left kidney through the renal artery of a normal Sprague Dawley rat. At least 1 x 106 RMCLZ1 was required for effective gene delivery into glomeruli. One hour and 1, 4, and 14 d after injection, glomeruli were isolated from the left kidneys injected with the cells and the expression of -galactosidase in each glomeruli was evaluated. One hour and 1 d after injection, more than 90 and 80%, respectively, of glomeruli from the left kidney showed strong -galactosidase activity, while no activity of -galactosidase was found in the glomeruli from the right kidneys. The number of glomeruli stained by X-gal and the intensity decreased with time. Fourteen days after injection, about 35% of the glomeruli retained the RMCLZ1. X-gal and periodic acid-Schiff staining of frozen sections obtained 14 d after injection allowed the estimation of the site where the mesangial cells injected were located. The mesangial cells were found mainly in two different locations, the glomerular capillary and the mesangium. The majority (about 90%) of the mesangial cells were located in the glomerular capillary and about 9% of the cells were in the mesangial area. Occasionally, the positive staining was found in proximal tubules and the interlobular artery. Although additional methods are required for the site-specific targeting of the mesangial area, the ex vivo gene transfer to glomerli uis feasible and may be a useful tool for future investigations in the pathological mechanisms of glomerular injury.  相似文献   

18.
Steroid hormone binding receptors in the rat kidney   总被引:3,自引:0,他引:3  
Summary The histochemical localization of 5-3-HSDH in individual follicles isolated from the adult mouse ovary and in ovulated cumulus cell-oocyte masses recovered from the oviduct was examined using a new embedding technique. The procedure employed involves the histochemical staining of such tissue for 5-3-HSDH with subsequent embedding in GMA (glycol methacrylate). This method not only permits the acquisition of sections as thin as 3 m but also preserves the histological detail of the tissue allowing for the specific cellular localization of the enzyme. Results obtained from this technique far surpass those obtained from frozen material. Virgin female mice were injected with PMSG and sacrificed either 10 or 17 h later in order to acquire preovulatory or ovulated oocyte-cumulus cell masses, respectively. The sites of localization of 5-3-HSDH corresponded to sites demonstrated by histochemical studies on frozen tissue sections; however, the present study revealed that not all cells of a specific type within the same follicle reacted with the same intensity. Granulosa cells lining the walls of vesicular follicles displayed different degrees of enzyme activity based on their distance from the basement membrane. Intrafollicular transformed cumulus masses and cumulus cells of ovulated masses within the oviduct did not react uniformly in that some were positive for the enzyme and others were not. Such results indicate that not all cells of a given type in the ovary possess similar 5-3-HSDH activity at a particular time. Thus, the cells comprising a specific cellular component of the ovary should be treated as individual entities and not as a homogeneous group with respect to their metabolic activities.This project was supported by Grant 1 RO1 OH 00835-01 awarded by the National Institute for Occupational Safety and Health and by a grant from the Edward G. Schlieder Foundation awarded to W.J.S. and NIH Grant 5 RO1 HD08041-03 awarded to A.W.S.  相似文献   

19.
B. Czeczuga 《Hydrobiologia》1980,69(3):277-279
The author investigated the presence of various carotenoids in Sardina pilchardus Walb. from the coast of Southern Europe.The presence of the following carotenoids has been stated: -carotene, -carotene epoxide, -cryptoxanthin, canthaxanthin, lutein epoxide, zeaxanthin, astaxanthin (free and ester form) and mutatochrome. The dominant carotenoid in all the parts of the body was astaxanthin, especially its ester form. The total content of carotenoid ranged from 10.537 (skin and muscles) to 116.309 µg/g fresh weight (liver).  相似文献   

20.
The sialidase of swine influenza A viruses of N1 and N2 subtypes, isolated from 1930 to 1992, was studied for substrate specificity with ganglio-series, lacto-series type II and GM3 gangliosides containing Neu5Ac2-3Gal, Neu5Gc2-3Gal and Neu5Ac2-6Gal linkages. All viral sialidases tested showed that the activity for hydrolysing substrates with Neu5Ac2-3Gal was higher than the activities with Neu5Gc2-3Gal and Neu5Ac2-6Gal linkages. When GM1b, GM3 and sialylparagloboside were used as substrates, the earliest strain (A/Wisconsin/15/30 H1N1, isolated in 1930) showed the activity ratio of Neu5Ac2-6Gal to Neu5Ac2-3Gal to be 0.13:0.2, and the ratio Neu5Gc2-3Gal/Neu5Ac2-3Gal to be 0.19:0.37, while those strains isolated from 1978 to 1992 exhibited ratios of 0.29:0.58 for Neu5Ac2-6Gal/Neu5Ac2-3Gal and 0.51:0.76 for Neu5Gc2-3Gal/Neu5Ac2-3Gal. The above results indicate that the substrate specificities of sialidases from swine influenza A viruses towards sialyl linkages and the molecular species of sialic acid are related to the year of isolation, i.e. strains isolated after 1978 exhibited higher activity towards Neu5Ac2-6Gal and Neu5Gc2-3Gal linkages when compared with strains isolated in an earlier year, 1930.Abbreviation Neu5Ac 5-N-acetylneuraminic acid - Neu5Gc 5-N-glycolyneuraminic acid - Gal d-galactose - Glc d-glucose - Cer Ceramide - II3(Neu5Ac)Lac Neu5Ac2-3Gal1-4Glc - GM3(Neu5Ac2-3Gal) Neu5Ac2-3Gal1-4Glc1-Cer - GM3(Neu5Gc2-3Gal) Neu5Gc2-3Gal1-4Glc1-Cer - GM1b(Neu5Ac2-3Gal) Neu5Ac2-3Gal1-3GalNac1-4Gal1-4Glc1-Cer - GMlb(Neu5Gc2-3Gal) Neu5Gc2-3Gal1-3GalNAc1-4Gal1-4Glc1-Cer - IV3(Neu5Ac)nLc4Cer Neu5Ac2-3Gal1-3GlcNAc1-4Gal1-4Glc1-Cer - IV3(Neu5Gc)nLc4Cer Neu5Gc2-3Gal1-3GlcNAc1-4Gal1-4Glc1-Cer - IV6(Neu5Ac)nLc4Cer Neu5Ac2-6Gal1-3GlcNAc1-4Gal1-4Glc1-Cer - TDC taurodeoxycholate.  相似文献   

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