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排序方式: 共有128条查询结果,搜索用时 343 毫秒
1.
Fabien Génin Ayabulela Yokwana Nokuthula Kom Sébastien Couette Thibault Dieuleveut Stephen D Nash 《African Zoology》2016,51(3):135-143
The primate fauna of South Africa has historically been viewed as comprising three diurnal cercopithecoid taxa – chacma baboons (Papio ursinus), vervet (Chlorocebus pygerythrus) and samango monkeys (Cercopithecus albogularis) – and two nocturnal lorisoid species – the thick-tailed greater galago (Otolemur crassicaudatus) and the southern lesser galago (Galago moholi). Here we report the positive identification of a third galago species within South Africa’s borders: the Mozambique dwarf galago or Grant’s galago, Galagoides granti (Thomas and Wroughton, 1907). The taxon was previously held to be restricted to Mozambique, eastern Zimbabwe, Malawi and Tanzania, but we have also observed it in the sand forest of Tembe Elephant Park and the Tshanini Community Reserve, near the Mozambique border. The species was formerly mistaken for Galago moholi, erroneously (we believe) extending the range of the latter species into northern KwaZulu-Natal. In South Africa the two small galagos are unlikely to have overlapping ranges: Galago moholi prefers dry savanna woodlands, whereas Galagoides granti is apparently confined to dry sand forest. However, both species may coexist with the larger and more widespread Otolemur crassicaudatus, an inhabitant of moist savanna, forest edge and thicket. The true South African ranges of both small galago species need to be ascertained. 相似文献
2.
Relave F Lefebvre RC Beaudoin S Price C 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(8):823-826
The aim of this study was to validate an enzyme-linked immunosorbent assay (ELISA) for the measurement of progesterone (P4) in mares. Specifically, the objectives were as follows: (1) to determine the specificity and sensitivity of the ELISA test for determination of P4, (2) to measure the potential agreement between the 2 people performing the test, and 3) to evaluate the effect of time on the outcome. Ten mares were sampled on the day before ovulation (D-1), and on days 1 (D1), 3 (D3), and 5 (D5) following ovulation, during the reproductive season. While mares were cycling regularly, estrus was induced by the injection of 5 mg of prostaglandin (PGF2) and monitored starting on the 4th day by daily transrectal palpation and ultrasonography to determine the time of ovulation. Blood was collected and all samples (n=96) were assayed for P4 by a semiquantitative ELISA, by chemiluminescent immunoassay, and by radioimmunoassay (RIA). Based on the RIA, values of P4 on D-1, D1, D3, and D5 were significantly different (P < 0.0001) with mean and standard deviation(s) of 0.004, s = 0.52; 2.05, s = 2.58; 8.37, s = 4.17; and 12.76, s = 4.00 ng/mL respectively. The sensitivity and specificity of the semiquantitative assay were 94% and 95%, respectively for the lowest values of P4 (< 1.0 ng/mL). The value of kappa was 0.90 between 2 individuals performing the test. In conclusion, these results suggest that the semiquantitative test may be used reliably and economically to evaluate P4 levels in equine plasma in the clinical 相似文献
3.
Difference in factors explaining growth rate variability in European eel subpopulations: the possible role of habitat carrying capacity 下载免费PDF全文
Clarisse Boulenger Alain J. Crivelli Fabien Charrier Jean‐Marc Roussel Eric Feunteun Anthony Acou 《Ecology of Freshwater Fish》2016,25(2):281-294
As a key parameter in the management of fish populations, individual growth rate (GR) variations were examined in the European eel (Anguilla anguilla; > 150 mm) using extensive mark–recapture surveys in the lotic habitats of two small rivers of western France: the Frémur, supposed to be saturated, and at the same latitude, the Oir with densities fivefold lower than those of the Frémur. In both systems, generalised linear models were used to test whether spatiotemporal factors such as dominant habitat type or local density affect GR variability. In the presumed unsaturated system, the Oir, GR variability is mainly explained by a set of habitat suitability drivers (density, dominant habitat type). In the Frémur, GRs appear independent of differences in habitat density or productivity. Below saturation, an increase in density will decrease the GR through intraspecific competition. At saturation, intraspecific competition reaches such high levels that regardless of eel density and productivity, the resources available by individual are similar throughout the system. In these circumstances, the effect of density on growth was presumed undetectable. Despite these contrasted results, mean GRs observed in both catchments were closed (~20 mm·year?1). This is an unexpected result as GR is expected to be higher in unsaturated systems. This similarity could be explained by the difference between the two systems in terms of: (i) sex ratio (the Frémur is dominated by male, whereas the female is dominant in the Oir), (ii) habitat type distribution or (iii) possible interspecific competition (important salmonid populations in the Oir). 相似文献
4.
The essential oil of Artemisia annua aerial parts, consisting of camphor (44%), germacrene D (16%), trans-pinocarveol (11%), beta-selinene (9%), beta-caryophyllene (9%) and artemisia ketone (3%), was screened for its antimicrobial activity. The essential oil remarkably inhibited the growth of tested Gram-positive bacteria Enterococcus hirae and both tested fungi. This oil has shown an antioxidant activity equivalent to 18% of the reference compound (alpha-tocopherol). 相似文献
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6.
Summary Starch gel electrophoresis was used to assess isozyme polymorphism in two Manihot species. Crude extracts were obtained from leaves and pollen. Ten enzymes were examined for their polymorphism in a germplasm collection of 365 cultivated plus 109 wild accessions, mainly from Africa. The inheritance of these enzymes was examined using 13 intra and interspecific progenies. Seventeen polymorphic loci were found for the ten enzyme systems, with 59 alleles. All the markers showed disomic heredity and three linkage groups were identified. 相似文献
7.
The multiple functional properties of egg yolk are mostly influenced by its complex protein composition. The high lipid content of egg yolk as well as the low solubility of delipidated egg yolk lipoproteins make analysis by conventional chromatographic or electrophoretic techniques a difficult task. This work describes a method to profile egg yolk proteins after delipidation with acetone using sodium dodecyl sulfate polyacrylamide gel electrophoresis on precast 8-18% T polyacrylamide gradient gels. Twenty bands were obtained for the whole egg yolk profile with molecular weights ranging between 5 and 221 kDa. The bands were identified based on their molecular weight and by comparison with isolated egg yolk subfractions. The dissociation behavior under reducing and nonreducing conditions provided additionally helpful information for identification and characterization of the yolk proteins. The method presented is very well suited for assaying the thermal sensitivity of whole yolk and its components and thus for the characterization of heat treatment processes. 相似文献
8.
Robert F Vuataz G Pollien P Saucy F Alonso MI Bauwens I Blank I 《Journal of agricultural and food chemistry》2005,53(11):4628-4632
The formation of acrylamide was investigated in model systems based on asparagine and glucose under low moisture Maillard reaction conditions as a function of reaction temperature, time, physical state, water activity, and glass transition temperature. Equimolar amorphous glucose/asparagine systems with different water activities were prepared by freeze drying and were shown to quickly move to the rubbery state already at room temperature and a water activity of above 0.15. The acrylamide amounts were correlated with physical changes occurring during the reaction. Pyrolysis and kinetics of acrylamide release in amorphous and crystalline glucose/asparagine models indicated the importance of the physical state in acrylamide formation. In amorphous systems, acrylamide was generated in higher concentrations and at lower temperatures as compared to the crystalline samples. Time and temperature are covariant parameters in both systems affecting the acrylamide formation by thermal processes. On the other side, the water activity and glass transition temperature do not seem to be critical parameters for acrylamide formation in the systems studied. 相似文献
9.
Masotti V Juteau F Bessière JM Viano J 《Journal of agricultural and food chemistry》2003,51(24):7115-7121
The volatile components of the aerial parts of Artemisia molinieri, an endemic wormwood of southern France, were analyzed by GC and GC-MS. Among the 69 compounds identified, major components were ascaridole (19-76%), alpha-terpinene (traces-36%), p-cymene (1-17%), 1,8-cineole (0.3-8%), and germacrene D (0.6-15%). Quantitative variations have been characterized following the season, the phenological cycle, and the aging of the plants. Bioassays have been performed on a sample of essential oil, which has shown a strong inhibition of the growth of both tested yeasts (Candida albicans and Saccharomyces cerevisiae var. chevalieri) and minor activity on both tested Gram-negative bacteria (Escherichia coli and Enterococcus hirae). The oils have shown interesting antioxidant activities on the basis of alpha-tocopherol as reference compound, up to 400-1200%. 相似文献
10.
Summary The use of random amplified DNA fragments as genetic markers in Coffea was investigated. Arbitrary oligonucleotides were used as primers to amplify genomic DNA of different coffee accessions representing major Coffea species by polymerase chain reaction. Intraspecific variation was easily detected in C. canephora and C. liberica whereas the primers assayed failed to reveal polymorphism between C. arabica accessions. Extensive interspecific variation was observed. Genetic relationships between Coffea species are deduced from the degrees of similarity in amplified product profiles. Random amplified DNA markers appeared to be of high value for characterization, analysis and utilization of coffee genetic resources. 相似文献