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971.
Use of a male-specific DNA probe to distinguish female mosquitoes of the Anopheles gambiae species complex 总被引:1,自引:0,他引:1
Abstract. A method has been developed to distinguish between mated female individuals of the sibling species Anopheles gambiae Giles sensu stricto and Anopheles arabiensis Patton. The DNA probe pAnal, reported by Gale & Crampton (1987a) to be useful for the specific identification of An.arabiensis males, is here shown to be sufficiently sensitive to deduce the species identity of inseminated females from the identity of the sperm contained within the spermatheca. 相似文献
972.
The characteristics of serial cross-sections of hairs collected from an adult male Japanese monkey were investigated. Cross-sections
were made of five to eight pieces per hair. The shapes of the cross-sections were elliptical or rounded on the whole. The
fibre indices of the sections ranged from 83 to 100. In particular, those of proximal (basal) sections were close to 100.
The hair diameter was 86.4 μ at maximum and 27.2 μ at minimum. A tendency was observed for the longer hairs to have thicker
diameters. The changes in thickness along the fibre shaft were slightly different in relation to hair length. The thickest
point was at around the middle of the fibre in the intermediate hair, somewhat towards the top of the central part in the
long hair, and somewhat towards the base in the short hair. The hair of the Japanese monkey, however, was considered to be
scanty in changes along the fibre shaft in comparison with many other animals. Medullae could scarcely be seen in the short
hair and in the terminal and proximal sections of all hairs. Their shapes in cross-section were not uniform and rough at the
margins. The fibre-medulla indices were generally less than 30 and smaller than those of many other mammals. Pigmentary granules
were observed in all sections examined. The granules were black-grey in sections of the black-grey coloured part and yellow
in the yellowish sections. They were dense in distal sections and scarce in sections close to the base. The cross-sectional
appearance of the thickest part of the long hair was considered to be useful for hair identification, since it was good in
pigmentation and medullation and relatively small fibre index. 相似文献
973.
J. S. C. Smith O. S. Smith 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1988,76(1):97-107
Summary Separations of kafirin and alcohol soluble glutelin proteins by reversed-phase high-performance liquid chromatography (RP-HPLC) from 7 inbreds and one hybrid of sorghum [Sorghum bicolor (L.) Moench] and one source of Johnsongrass [Sorghum halapense (L.) Pers.] were compared. Objectives were to assess the stability of protein profiles for seed sources produced at different locations and in different environments to examine the potential of RP-HPLC to provide genotypic profiles for sorghum. Analyses of variance data showed that levels of variation due to environments and locations were small; the majority of variation (93%) was among genotypes. Associations among inbreds revealed by multivariate and cluster analysis showed similarity with those that would be expected on the basis of pedigree. A chi-square analysis showed no deviation in the hybrid profile from the expected 21 ratio of peaks from the female and male inbred parents, respectively. Improvements in the ability to correctly assign common peaks are necessary before associations among numerous sorghum genotypes can be reliably demonstrated by analysis of data from reversed-phase high-performance liquid chromatography (RP-HPLC). 相似文献
974.
T. A. McMeekin 《Hydrobiologia》1988,165(1):35-40
Bacteria isolated from antarctic sea and lake water samples were examined for growth at 5 °C and 25 °C. Of 250 isolates, 249 were psychrotrophic and one was psychrophilic. The effect of temperature on the growth rate of the latter (strain 755) and a typical psychrotroph (strain 203A) was described by the square root of the growth rate constant. TMIN values calculated from this model confirmed the strains as psychrophile and psychrotroph.Identification of 93 isolates showed the majority to be Pseudomonas (82%), with Flavobacterium and Moraxella representing 13% of the isolates. The remainder were coryneforms and yeasts. Isolate 611 was studied in detail because of its unusual morphology. This strain has features in common with the genera Spirosoma, Runella and Flectobacillus, but cannot be assigned with certainty. It may represent a new taxon of curved, gram negative bacteria. 相似文献
975.
D B Spring C O Lovejoy G N Bender M Duerr 《American journal of physical anthropology》1989,79(2):247-252
Deep preauricular sulci were identified on abdominal radiographs in 29 of 190 (15%) adult females and in none of 110 adult males. To assess the value of the deep preauricular sulcus as an index of past pregnancy, we examined gravidity and parity records of 190 women, using standard films that included the sacroiliac region. Deep, radiographic preauricular grooves were identified in 4 of 41 (10%) nulliparous women and in 25 of 149 (17%) women with positive pregnancy histories. We also examined radiographs obtained before and after pregnancy in six primigravidas. No evidence of radiographic changes in the preauricular grooves was seen in any of the six women. We conclude that the presence of a deep, radiographic preauricular sulcus is not necessarily an indication of past pregnancy. 相似文献
976.
Twenty known gibberellins (GAs) have been identified by combined capillary gas chromatography-mass spectrometry in extracts from less than 10 g fresh weight of maturing seeds of the cucurbit Sechium edule Sw. The GAs are predominantly 3- and-or 13-hydroxylated. This is the first reported identification of non-conjugated 13-hydroxylated GAs in a cucurbit. Gibberellin A8 and gibberellin A8-catabolite are the major GAs in terms of quantity and are largely accumulated in the testa. The catabolites of 2-hydroxylated GAs are ,-unsaturated ketones which no longer possess of a -lactone. They were hitherto known only in legumes. The presence of GA8-catabolite as a major component of Sechium seeds indicates that the distribution of these GA-catabolites may be more widespread than previously envisaged. The localization of known GAs in maturing seeds of the legume Phaseolus coccineus L. was found to resemble closely that in Sechium. Gibberellin A8, a putative conjugate of GA8 and GA8-catabolite are accumulated in the testa. The localization in the testa of end-products of the GA-biosynthetic pathway, which was first observed in maturing seeds of Pisum sativum, and is now described in Phaseolus and Sechium, may be a general feature of seed development.Abbreviations GAn
gibberellin An
- GC-MS
combined gas chromatography-mass spectrometry 相似文献
977.
大青(Clerodendrum cyrtophyllum)是苗族地区常用的药用植物。为研究黔产大青的化学成分及其抗菌活性,该研究采用大孔吸附树脂、反相柱色谱、硅胶柱色谱、Sephadex LH-20柱色谱、半制备高效液相色谱等方法对大青95%乙醇提取物进行分离和纯化,并根据波谱数据鉴定所得化合物结构,采用MTT法评价其抗菌活性。结果表明:从大青中分离得到18个化合物,分别鉴定为木栓酮(1)、α-amyrin palmitate(2)、sambuculin A(3)、22-dehydroclerosterol(4)、isopetasin(5)、taraxasteryl palmitate(6)、豆甾醇(7)、22-dehydroclerosterol-3-O-β-D-(6′-O-margaroyl)-glucopyranoside(8)、3-O-β-D-galactopyranosyl-(24β)-ethylcholesta-5,22,25-trien(9)、肉苁蓉苷D(10)、tortoside F(11)、balanophonin(12)、木犀草苷(13)、类叶升麻苷(14)、木犀草... 相似文献
978.
Patrick J. Weatherhead Katherine E. Muma J. Dylan Maddox Jenny M. Knox Kevin W. Dufour 《Journal of Field Ornithology》2007,78(4):428-435
ABSTRACT. Past studies of offspring sex ratios in birds have often relied on sexually size dimorphic species where nestling sex could be determined based on weight at a given age. DNA-based sexing techniques allow us to assess the accuracy of those techniques and to refine them for use when costs or convenience make DNA methods impractical. Using nestling Red-winged Blackbirds ( Agelaius phoeniceus ) whose sex was determined using DNA, we compared sex ratios obtained using different morphological criteria. Conservative criteria from previous studies were completely accurate, but allowed sexing of few nestlings younger than 8 d old, and were more successful for sexing males than females. A new method was developed that allowed accurate sexing of nestlings beginning at day 6 posthatching and was less biased relative to known sex ratios. Using 11 years of data, the conservative method left an average of 55% of nestlings and 36% of fledglings unsexed, compared to 31% and 9% using the new method. Furthermore, the male bias in sex ratio estimates using the conservative method was greater, both absolutely and relative to estimates based on the new method, when the proportion of unsexed nestlings (because they were not weighed when older) was higher. Thus, estimates of population sex ratios will be more accurate as the number of nestlings measured on day 8 or older increases. However, if some nestlings that were not weighed past day 7 fledge, the new method allows more of those individuals to be sexed than the conservative method, and the population sex ratio estimate should be more reliable. Although our approach should apply to other sexually dimorphic species, the criteria used must be developed based on such species-specific attributes as growth patterns and degree of hatching asynchrony. 相似文献
979.
980.
Onchocerca volvulus and Mansonella ozzardi are two human filarial parasites present in South and Central America. In the Brazilian Amazonia they are found in sympatry, and the lack of clear morphological diagnostic characters in the microfilariae hinders their identification. The major sperm protein (MSP) gene of both species has been sequenced and characterised to determine its potential as a molecular diagnostic character. The length of the MSP gene is different in each species, and this could be used to detect and differentiate them by running the polymerase chain reaction (PCR) product in an agarose gel. Two major gene groups were identified in O. volvulus with a genetic distance of 6% between them. In M. ozzardi only one major group of genes was observed. The high similarity between the protein amino acid sequence of both filarial species confirms that the MSP has been highly conserved through nematode evolution. 相似文献