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1.
J. Hojný 《Animal genetics》1973,4(3):161-168
The haemolytic reagent allowing direct serological detection of He homozygous pigs was obtained by the immunization of a Landrace sow. Another monospecific reagent prepared from immune serum of a Miniature pig made possible the evidence for a new factor of the H system - He. This factor is genetically controlled by the allele H be. Its frequency in Miniature pigs was 0.099.
The H system with alleles H 1=Ha, H2= Hb, H3= Hab, H4=Hcd, H5= Hbd, H6=Hbe and H7= H- continues to be a genetically open system.  相似文献   

2.
Two new erythrocyte antigens have been detected by isoimmune antibodies obtained from Gottingen Miniature pigs. By family studies they proved to belong to the E system. The factor designated En is genetically controlled by alleles E 2= E edghkmn, E 3= E aegln, E 4= E edfhkmn, E 6= E aefln, E 9= E edghjmn, E 12= E aegmno and E edgkln, and the factor designated Eo by the allele E 12= E aegmno.
The En blood factor occurs in all the breeds studied and in frequency it comes close to a related Ee factor. It stands in opposition not only to Eb but also to Ei factor. The Eo factor can be characterized as a rarely occurring Ea subgroup. Besides being antithetic to Ed it is also antithetic to El and Ei factors. For the present, it was found only in Miniature pigs.  相似文献   

3.
The aim of the present study was to estimate the genetic, shared and nonshared environmental contributions to self-reported and parent-reported internalizing and externalizing problems in a follow-up study of intercountry adopted young adults. Young Adult Self-Report ratings were obtained from 1475 adoptees aged 22–32 years and Young Adult Behavior Checklist ratings from 1115 adoptive parents. For the genetic analyses, a subset of 143 adopted biologically related and 295 unrelated siblings was used. The data were subjected to model fitting decomposing three sources of variance: genetic factors (A) shared environment (C) and nonshared environment (E). Genetic factors were of more importance in both self-reported ( A 2= 54%, C 2= 0, and E 2= 46%) and parent-reported ( A 2= 76%, C 2= 15% and E 2= 9%) internalizing problems. Environmental factors were of more importance in both self-reported ( A 2= 33%, C 2= 17% and E 2= 50%) and parent-reported ( A 2= 28%, C 2= 27% and E 2= 45%) externalizing problems. This was in contrast with findings from the first and second assessments in the same sample during adolescence when genetic factors were more important in explaining externalizing problems compared with internalizing problems. Our results suggest a developmental reversal in genetic and environmental influences on behavior problems from early adolescence into adulthood, which could be related to different underlying developmental trajectories.  相似文献   

4.
Effect of temperature on swimming performance of sea bass juveniles   总被引:1,自引:0,他引:1  
At four temperatures ( T= 15, 20, 25 and 28° C) swimming performance of Dicentrarchus labrax was significantly correlated with total length (23–43 mm L T); r2=0.623–0.829). The relative critical swimming speed ( RU crit= U crit L T−1), where U crit is the critical swimming speed, was constant throughout the L T range studied. The significant effect of temperature on the relative critical swimming speed was described binomially: RU crit=−0.0323T2+ 1.578 T −10.588 (r2=1). The estimated maximum RU crit (8.69 L T s−1) was achieved at 24.4° C, and the 90% performance level was estimated between 19.3 and 29.6° C.  相似文献   

5.
Abstract. Measurements of the water-relation parameters of the giant subepidermal cells (volume, V = 0.119 to 1.658 mm3; = 0.53±0.35 mm3, SD, n = 23) and the smaller mesocarp parenchyma cells ( V = 0.10 to 0.79×10−3 mm3; = 0.36±0.27×10−3 mm3, SD, n = 6) of the inner pericarp surface of Capsicum annuum L. were made using the Jülich pressure probe. The volumetric elastic modulus ɛ for the large cells was between 1.5 and 27 MPa for a pressure range of 0.09 to 0.41 MPa. For the small cells ɛ was 0.1 to 0.6 MPa for a pressure range of 0.22 to 0.39 MPa. The turgor pressure P , the half-time of water exchange T 1/2, and the hydraulic conductivity L p were as follows, with SD and number of replicates: large cells, P = 0.27±0.06 MPa (23), T 1/2=2.7±2.2 s (46), L p=5.8±3.7 pm s−1 Pa (46); small cells, P = 0.33±0.07 MPa (6), T 1/2= 33±10s (12), L p=0.21±0.07 pm s−1 Pa−1 (12). The determination of these basic water-relation parameters is considered as a prerequisite for future ecotoxicological and phytopathological studies. The differences between the large and the small cells are discussed in relation to a desirable biophysical definition of succulence. Further, for the large cells a pressure and volume dependence of ɛ was demonstrated.  相似文献   

6.
Nine strains of three novel anamorphic yeast species were obtained from samples collected in Thailand including six strains (RV96, RV152, R14, RS9, RS58 and EA1) obtained from estuarine waters collected from two mangrove forests, one strain (ST84) from insect frass and two strains (SR16 and UB13) from forest soils. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the nine strains were found to represent three novel Candida species in the Saturnispora clade. Five strains (RV96, RV152, R14, RS9 and RS58) were assigned as a single novel species, which was named Candida sanitii sp. nov. The type strain is RV152T (BCC 25967T=NBRC 103864T=CBS 10864T). Strain EA1 was named as Candida suwanaritii sp. nov. The type strain is EA1T (BCC 29900T=NBRC 104877T=CBS 11021T). Three strains (ST84, SR16 and UB13) represented another novel species, for which Candida sekii sp. nov. is proposed. The type strain is ST84T (BCC 8320T=NBRC 105671T=CBS 10931T).  相似文献   

7.
The acute toxicity of copper, zinc and manganese and copper-zinc and copper-manganese mixtures were determined for juvenile longfin dace, Agosia chrysogaster in hard water bioassays (mean=218 mg 1−1 CaCO3). Copper-zinc was the most lethal toxicant (96-h L.c.50= 0.21 mg 1−1 copper and 0.28 mg 1−1 zinc) and exhibited a more than additive toxicity which was in contrast to the additive toxicity of copper-manganese mixtures (96-h L.c.50= 0.45 mg 1−1 copper and 64.0 mg 1−1 manganese). The toxicity of copper (96-h L.c.50= 0.86 mg 1−1) and zinc (96-h L.c.50= 0.79 mg 1−1) to the fish was similar but both were considerably more lethal than manganese (96-h L.c.50= 130 mg 1−1).  相似文献   

8.
SUMMARY. The oxygen consumption of shrimps ranging from 1 to 30 mg dry mass was determined at 18, 24 and 30°C using a continuous flow recording respirometer based upon a Clark-type oxygen electrode. Respiration (ascribed to routine metabolism) is described by the power curve: R = a Mb , ( R =μg O2 h−1, M = mg dry mass), which gives values of a = 1.632, 2.564 and 4.181, and b = 0.800, 0.898, and 0.793, at 18, 24 and 30°C respectively. The single expression, R = 0.008 T 1.829 M 0.830 provides a reasonable prediction of respiration as a combined function of shrimp size ( M ) and temperature (T, °C). Using an energy equivalent of 14.14 J mg O2−1 estimates of the energy requirements ( E , J h−1 10−3) of routine metabolism are given by the expression: E = 0.115 T 1.829 M 0.830.
Variability in oxygen consumption values between individuals is discussed and the observations on C. nilotica are compared with other crustacean studies.  相似文献   

9.
Three strains of aerobic, Gram-negative, rod-shaped, non-spore-forming, yellow-pigmented bacteria (OD1T, YOxT and NS13), which were isolated in previous studies by enrichment in a mineral medium with potassium oxalate as the sole carbon source, were characterized. On the basis of 16S rRNA gene sequence similarity, strains OD1T, YOxT and NS13 belong to the Betaproteobacteria , most closely related to Oxalicibacterium flavum TA17T (97.2–99.7% sequence similarity). The major whole-cell fatty acids were C16:0, C16:1ω7c and C17:0 cyclo. The results of DNA–DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strains OD1T and YOxT from O. flavum TA17T and from each other. Therefore, it is concluded that the strains OD1T and YOxT represent novel species within the genus Oxalicibacterium , for which the names Oxalicibacterium horti sp. nov. (type strain OD1T=DSM 21640T=NBRC 13594T) and Oxalicibacterium faecigallinarum sp. nov. (type strain YOxT=DSM 21641T=CCM 2767T) are proposed.  相似文献   

10.
A procedure for the partial purification of a non-specific alkaline phosphatase (EC 3.1.3.1.) from the embryonic axes of chick-pea seeds is described. Ammonium sulphate precipitation, DEAE-cellulase chromatography, Sephacryl S-200 chroma-tography and polyacrylamide gel electrophoresis are the most important steps. The molecular weight of this non-specific enzyme, as determined by Sephacryl S–200 gel filtration and SDS–polyacrylamide gel electrophoresis, was estimated as being 68 and 78 kDa respectively; the optimum pH for p-nitrophenylphosphate hydrolysis was 7.5, and the Km for this artificial substrate was 0.5 mM. The enzyme catalyzes the hydrolysis of a variety of organic phosphate esters. The best substrates are: phos-phoenolpymvate (Km= 2.4 m M ), NADP+ (Km= 4.0 m M ), 5'-AMP (Km= 4.5 m M ), 5'-ADP (Km= 6.1 m M ) and ribose-5P (Km= 5.8 m M ); but it is unable to hydrolyze 5'-ATP, phosphocreatine and tripolyphosptiate. Phospate was a competitive inhibitor. Zn2+, K+, Hg2+ and Mo6+ were strong inhibitors, whereas F and Ca2+ inhibited weakly; Co2+ and Ni2+ were activators.  相似文献   

11.
Studies were carried out on the polymorphism of alkaline ribonuclease in Black-and-White cattle in the north-eastern region of Poland. Leucocytes isolated from peripheral blood were used. Three phenotypes were defined, consisting of the combination of two alleles. The gene frequency was: q4= 0,7082, qB= 0,2918. In calves the frequency of allele RNA-aseB and number of RNA-aseA/ RNA -aseB heterozygotes were higher than in adult animals.  相似文献   

12.
Mean values of the composition of the seminal fluid of 30 turbots were: osmotic pressure =306 mosml−1, pH =7–31, total protein =8.8mg ml1, Na+=133.0 mmoll1, K+=3.80mmoll−1, Cl=129mmol l−1. The rounded nucleus, the reduced middle piece and the typical '9 + 2' structure of the flagellum mean that the spermatozoon of turbot can be considered to be of a primitive type.  相似文献   

13.
K. Christian    B. Green    G. Bedford    K. Newgrain 《Journal of Zoology》1996,240(2):383-396
The field metabolic rates (FMR) and water fluxes of Varanus scalaris were measured during the wet and dry seasons by the doubly-labelled water technique. Seasonal measurements of standard (night-time) metabolism (SMR) and resting (daytime) metabolism (RMR) were made in the laboratory at 18, 24, 30 and 36°C, and maximal oxygen consumption was measured at 36°C on a motorized treadmill. This population was active throughout the year. In the wet season, the mean FMR was 7.8 kJ day−1 (128.0 kJkg−1 day−1; mean mass = 66.4 g, n = 13), and during the dry season the mean was 5.0 kJ day−1 (67.6 kJ kg−1 day−1; mean mass = 77.4 g, n = 17). The mean water flux rates for these animals were 3.6 and 1.2 ml day−1, respectively (60.4 and 16.6 ml kg−1 day−1). The seasonal means of FMR and water flux were significantly different by ANCOVA ( P < 0.0001). Measurements of SMR and RMR were significantly higher in the wet season (ANCOVA: P < 0.0001), but we found no difference in the maximal oxygen consumption between seasons (ANCOVA: P = 0.6). The maximal oxygen consumption of the lizards on the treadmill (2.9 ml min−1= 1.8 ml g−1 h−1), mean mass = 97.4 g, n = 16) was 20 times that of the SMR at the same temperature during the dry season, and 11 times that of the SMR during the wet season. The seasonal differences in FMR were attributable to: changes in SMR (12.2%) and RMR (16.4%); differences in night-time body temperatures (11.3) and daytime body temperatures (16.4%); and activity (broadly defined to include locomotion, digestion, and reproductive costs (43.7%).  相似文献   

14.
Abstract: In cultured bovine adrenal medullary cells, stimulation of nicotinic receptors by carbachol evoked the Ca2+-dependent exocytotic cosecretion of proadrenomedullin N-terminal 20 peptide (PAMP) (EC50 = 50.1 µ M ) and catecholamines (EC50 = 63.0 µ M ), with the molar ratio of PAMP/catecholamines secreted being equal to the ratio in the cells. Addition of PAMP[1–20]NH2 inhibited carbachol-induced 22Na+ influx via nicotinic receptors (IC50 = 2.5 µ M ) in a noncompetitive manner and thereby reduced carbachol-induced 45Ca2+ influx via voltage-dependent Ca2+ channels (IC50 = 1.0 µ M ) and catecholamine secretion (IC50 = 1.6 µ M ). It did not alter high K+-induced 45Ca2+ influx via voltage-dependent Ca2+ channels or veratridine-induced 22Na+ influx via voltage-dependent Na+ channels. PAMP seems to be a novel antinicotinic peptide cosecreted with catecholamines by a Ca2+-dependent exocytosis in response to nicotinic receptor stimulation.  相似文献   

15.
Adult Antarctic fur seals (Arctocephalus gazella) were immobilized with Zoletil® ( n = 172), ketamine ( n = 30), ketamine mixed with diazepam ( n = 23) and with ketamine mixed with xylazine ( n = 45). Response to all drugs was highly variable. There was a relationship between dose rate and level of immobilization in females given Zoletil®. Males were slightly more sensitive to Zoletil® than females but this could have been due to the greater body mass and lower mass-specific metabolic rate of males. The dose required to achieve a level of immobilization declined with greater body mass for Zoletil® and ketamine but not for ketamine-diatepam. Ketamine and ketamine-sedative mixtures commonly caused mild tremoring and occasionally caused convulsions. Neither reaction was seen with Zoletil®. Mean doses were, Zoletil® 1.5 mg/ kg, ketamine 6.9 mg/kg, ketamine-diazepam 6.3 mg/kg ketamine and 6.3 μg/kg diazepam, and ketamine-xylazine 7.3 mg/kg ketamine and 0.62 mg/ kg xylazine. Zoletil® performs at least as well on Antarctic fur seals as ketamine but it may cause respiratory depression. The dose of ketamine required for Antarctic fur seals was greater than for most other species of seals.  相似文献   

16.
The metamorphosis of Solea senegalensis was studied in larvae reared at 20° C and fed four different feeding regimes. A, Artemia (4 nauplii ml−1); B, Artemia (2 nauplii ml−1); C, mixed diet (2 nauplii ml−1 and 3 mg ml−1 microencapsulated diet); and D, microencapsulated diet (3·7 mg ml−1). Rotifers were also supplied in all cases during the first days of feeding. These feeding regimes supported different growth rates during the pre-metamorphosis period (regime A, G=0·376 day−1; regime B, G=0·253 day−1; regime C, G=0·254 day−1; regime D, G=0·162 day−1). Larvae started metamorphosis 9 days after hatching (DAH) when fed the regime A, 13 DAH with regime B, 11 DAH with regime C and 15 DAH with regime D. A minimum 5·6–5·9 mm LT was required under all feeding regimes to initiate the metamorphosis. Eye translocation was completed when the larvae reached 8·6–8·7 mm LT (regimes A, B and C), but only 7·3 mm LT with regime D. 4·4–6·2 days were required to complete eye migration under the regimes A, B and C, and 18·3 days under the regime D. This transformation is concomitant with changes in body reserves, and with the pattern of some digestive enzymes.  相似文献   

17.
Abstract: The voltage-dependent Na+ ionophore of various neuronal cells is permeable not only to Na+ ions but also to guanidinium ions. Therefore, the veratridine-(or aconitine-) stimulated influx of [14C]guanidinium in neuroblastoma × glioma hybrid cells was measured to characterize the Na+ ionophore of these cells. Half-maximal stimulation of guanidinium uptake was seen at 30 μ M veratridine. At 1 m M guanidinium, the veratridine-stimulated uptake of guanidinium was lowered to 50% by approximately 60 m M Li+, Na+, or K+ and by a few millimolar Mn2+, Co2+, or Ni2+. The basal, as well as the veratridine-stimulated, uptake of guanidinium was inhibited by the cholinergic antagonists (+)-tubocurarine ( Ki = 50 to 500 n M ) and atropine ( Ki = 5 to 30 μ M ) and the adrenergic antagonists phentolamine ( Ki = 5 μ M ) and propranolol ( Ki = 60 μ M ). The specificity of the inhibitory effects of these agents is stressed by the ineffectiveness of various other neurotransmitter antagonists. However, the corresponding ionophore in neuroblastoma cells (clone N1E-115) seems to be regulated differently. While phentolamine and propranolol inhibit the veratridine-activated uptake as in the hybrid cells, (+)-tubocurarine and atropine exert only a slight effect.  相似文献   

18.
Abstract. A field study was conducted to determine the relationship of solar-excited chlorophyll a fluorescence to net CO2 assimilation rate in attached leaves. The Fraunhofer line-depth principle was used to measure fluorescence at 656.3 nm wavelength while leaves remained exposed to full sunlight and normal atmospheric pressures of CO2 and O2. Fluorescence induction kinetics were observed when leaves were exposed to sunlight after 10 min in darkness. Subsequently, fluorescence varied inversely with assimilation rate. In the C4 Zea mays , fluorescence decreased from 2.5 to 0.8 mW m-2 nm-1 as CO2 assimilation rate increased from 1 to 8 μmol m-2 s-1 (r2= 0.520). In the C3 Liquidambar styraciflua and Pinus taeda , fluorescence decreased from 6 to 2 mW m-2 nm-1 as assimilation rate increased from 2 to 5 or 0 to 2 μmol m-2 s-1 (r2= 0.44 and 0.45. respectively). The Fraunhofer line-depth principle enables the simultaneous measurement of solar-excited fluorescence and CO2 assimilation rate in individual leaves, but also at larger scales. Thus, it may contribute significantly to field studies of the relationship of fluorescence to photosynthesis.  相似文献   

19.
The activity of the H+-pyrophosphatase (H+-PPase) was characterized in microsomes from 24-h-old radish ( Raphanus sativus L., ev. Tondo Rosso Quarantino) seedlings, which are virtually devoid of the tonoplast H+-ATPase. The H+-PPase was localized to membranes which roughly comigrated with the plasma membrane in a sucrose density gradient, but clearly separated from plasma membrane when microsomes were partitioned in an aqueous dextran-polyethylene glycol two-phase system. The H+-PPase activity was strictly dependent on Mg2+ and on the presence of a monovalent cation (K+=Rb+=NH3+Cs+≫Na+Li+) and was insensitive to anions such as Cl−, Br−, NO3− and SO42-. It was inhibited by F−, imidodiphosphate and Ca2+. It had a pH optimum between pH 7.5 and 8.5 and was saturated by low concentrations of pyrophosphate (half saturation at 30 μ M pyrophosphate). All of these characteristics are identical to those reported for the tonoplast H+-PPase from various plant materials. The functional molecular weight of the H+-PPase, measured with the radiation-inactivation technique was 96 kDa.  相似文献   

20.
Eggs were collected from two stocks of lake whitefish, Coregonus clupeaformis , in Lakes Michigan and Huron to assess the effect of egg composition and prey density on larval growth and survival. Egg composition parameters including wet weight (mg egg−1), dry weight (mg egg−1), percent water, total caloric content (cal egg−1), caloric density (cal egg−1), percent lipid content, and total lipidcontent (mg egg−1) were measured. Fish hatched from six parental females in each stock were fed one of four rations (0, 18, 24, 50 brine shrimp larva−1 day−1) after yolk sac absorption. Length at hatch, endogenous growth, exogenous growth, and survival were measured during a 42-day laboratory experiment. Length at hatch of larvae was positively related to egg caloric content ( r 2=0.780). Endogenous growth for lake whitefish larvae was positively related to percent lipid content ( r 2=0.896) and total egg lipid content ( r 2=0.876) of parental females. Exogenous growth and survival of larval lake whitefish was positively related to prey availability. Larval fish growth was accurately modelled ( r 2=0.973) as a function of prey abundance using a threshold-corrected hyperbolic equation. These results indicate that both egg composition and prey availability have the potential to influence the growth and survival dynamics of larval lake whitefish significantly.  相似文献   

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