排序方式: 共有29条查询结果,搜索用时 15 毫秒
1.
Nine pairs of polymerase chain reaction (PCR) primers that amplify polymorphic microsatellite loci in the desert locust, Schistocerca gregaria (Forskal), were developed using a magnetic bead‐based enrichment protocol. A sample of 48 locusts collected during the 1993 and 1995 upsurge periods in Eritrea, East Africa, were genotyped. The number of alleles per locus ranged from six to 20; the average was 12.67. Allelic distributions were significantly different between samples from different localities. 相似文献
2.
A. K. JAFRI SALEEM MUSTAFA ISHRAQ AHMAD 《Zoological Journal of the Linnean Society》1978,64(2):107-110
Investigations were made on the existence of size-hierarchy in specimens of Esomus danricus (Ham.) belonging to the same year-class, and the variations in condition factor of the different size-groups. Divergence in the growth rates of individual fish resulted in the development of size-hierarchy in the population. Marked changes seemed to occur in condition factor of the different size-groups. A multitude of factors operating simultaneously in the pond environment appeared to govern the condition factor of fish. 相似文献
3.
HENRY SILVERMAN BABIKER AHMED SAMAR AJEILET SUMAIA AL‐FADIL SUHAIL AL‐AMAD HADIR EL‐DESSOUKY IBRAHIM EL‐GENDY MOHAMED EL‐GUINDI MUSTAFA EL‐NIMEIRI RANA MUZAFFAR AZZA SALEH 《Developing world bioethics》2010,10(2):70-77
To help ensure the ethical conduct of research, many have recommended educational efforts in research ethics to investigators and members of research ethics committees (RECs). One type of education activity involves multi‐day workshops in research ethics. To be effective, such workshops should contain the appropriate content and teaching techniques geared towards the learning styles of the targeted audiences. To ensure consistency in content and quality, we describe the development of a curriculum guide, core competencies and associated learning objectives and activities to help educators organize research ethics workshops in their respective institutions. The curriculum guide is divided into modular units to enable planners to develop workshops of different lengths and choose content materials that match the needs, abilities, and prior experiences of the target audiences. The content material in the curriculum guide is relevant for audiences in the Middle East, because individuals from the Middle East who participated in a Certificate Program in research ethics selected and developed the training materials (e.g., articles, powerpoint slides, case studies, protocols). Also, many of the activities incorporate active‐learning methods, consisting of group work activities analyzing case studies and reviewing protocols. The development of such a workshop training curriculum guide represents a sustainable educational resource to enhance research ethics capacity in the Middle East. 相似文献
4.
5.
Differential application of lambda-cyhalothrin to control the sandfly Lutzomyia longipalpis 总被引:1,自引:0,他引:1
Abstract. To study the impact of residual pyrethroid insecticide on the abundance and distribution of peridomestic Lutzomyia longipalpis , the sandfly vector of visceral leishmaniasis in Brazil, lambda-cyhalothrin was applied at 20 mg a.i.m-2 in the following interventions: (i) spraying of all animal pens in a village (blanket coverage); (ii) treatment of a subset of animal pens, either by spraying, or by installation of insecticide-impregnated 1 m2 cotton sheets as 'targets' (focal coverage).
By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu. longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu. longipalpis in untreated dining-huts and houses. This differential impact on Ludongipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds.
Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu. longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans. 相似文献
By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu. longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu. longipalpis in untreated dining-huts and houses. This differential impact on Ludongipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds.
Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu. longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans. 相似文献
6.
MOON THOMAS W.; MUSTAFA TARIQ; HOCHACHKA PETER W. 《Integrative and comparative biology》1971,11(3):491-502
SYNOPSIS. Pyruvate kinase (PK) maximum catalytic rate is dramaticallydecelerated by increasing hydrostatic pressure. In four differentspecies inhabiting different portions of the water column, musclepyruvate kinase displays (1) a reduction in the volume changeof activation, V*. a t higher temperatures, (2) a pH independenceof V*, and (3) a general increase in the activation energy atincreased pressures. Although shared by the four different pyruvatekinases examined, none of these characteristics is criticallyinvolved in the regulation of PK catalysis. In contrast, pressureeffects on another set of characteristics, all vitally importantto control of PK catalytic function, depend upon the speciesorigin of the enzyme. In the case of the rainbow trout, Salmogairdneri, high pressure dramatically reduces pyruvate kinaseaffinities for the two substrates (PEP and ADP), the cationiccofactor (Mg2+), and the negative modulator (ATP). The homologousmuscle enzyme from Oligoplites mundus, another surface dwellingspecies, displays similar responses to pressure. On the otherhand, muscle PK affinities for the same key regulatory ligandsare much less pressure sensitive in the abyssal rattail fishes(Coryphaenoides sp.) and are essentially pressure independentin a vertically migrating midwater sea bass, Ectreposebastesimus. In these latter two species, PK catalytic rates underprobable physiological conditions are determined largely bythese kinetic properties rather than by energy-volume parameters. 相似文献
7.
KKES YILMAZ SAIT ELK MUSTAFA NAZIROLU MEHMET AY NIHAT DLSZ 《Cell biochemistry and function》1997,15(1):1-7
The object was to determine the influence of dietary vitamin E, selenium and their combination on the fatty acid con-tent of erythrocytes, bone marrow and spleen lipids of Akkaraman lambs. After supplementation for 15 days, the amount of all fatty acids was slightly higher (p < 0·05) in the vitamin E as compared to the control group, whereas the amount of longer fatty acids was significantly higher (p < 0·01, p < 0·001) in the selenium and combination groups. On the thirtieth day, the amount of all fatty acids was slightly high (p < 0·5) in all the supplemented groups in comparison with the control group. In the bone marrow lipids, the amount of longer fatty acids was decreased (p < 0·05, p < 0·01, p < 0·001) in the vitamin E and combination groups as compared to the control. Although the amount of some fatty acids was high (p < 0·05, p < 0·01) in the selenium group compared to the control, linoleic (18:2), linolenic (18:3) and the polyunsaturated fatty acids (PUFA) were lower (p < 0·05, p < 0·001). In the spleen lipids, the amount of longer fatty acids was slightly decreased (p < 0·05) in the vitamin E group as compared with the control; however the amount of longer fatty acids was significantly higher (p < 0·05, p < 0·01) in the selenium and combination groups in comparison to the control group. Thus dietary supplementation with selenium was more effective than dietary vitamin E supplementation in altering the fatty acid content of the erythrocyte, bone marrow and spleen lipids. © 1997 John Wiley & Sons, Ltd. 相似文献
8.
MOON THOMAS W.; MUSTAFA TARIQ; HOCHACHKA PETER W. 《Integrative and comparative biology》1971,11(3):473-478
SYNOPSIS. The predominant lactate dehydrogenases (LDH's) occurringin liver, heart, and muscle of a benthic Coryphaenoides speciesare electrophoretically distinguishable from each other. Maximumrates of pyruvate reduction catalyzed by heart and muscle LDH'sshow an optimum pH near neutrality, while liver LDH activitydisplays an unusual alkaline pH optimum. Pyruvate saturationcurves are Michaelis-Menten in form for all three preparations.Maximum catalytic rates and the apparent Km (pyruvate) are pressureindependent for liver and heart LDH's. In the case of muscleLDH's, the maximum catalytic rate is also pressure insensitive,but the Km is dramatically increased by pressure. These experimentsdearly indicate that, at low substrate concentrations, the preciseeffects of pressure on enzyme-catalyzed reactions depend uponthe nature and origin of the catalyst. 相似文献
9.
AMIR YASSIN AMIRA Y. ABOU-YOUSSEF BLANCHE BITNER-MATHÉ PIERRE CAPY JEAN R. DAVID 《Ecological Entomology》2007,32(6):698-706
Abstract. 1. During their development in natural conditions, Drosophila larvae and pupae face heterogeneous environmental conditions (HEC). Analysing the morphology of wild-living adults is a means of evaluating the effects of HEC.
2. Two drosophilid species of the Zaprionus genus that recently invaded the Nile delta were investigated, and three metric, size-related traits, and one meristic trait, the sternopleural bristle number, were measured. Data were compared with those of F1 generation reared under favourable laboratory conditions.
3. Body size was smaller in nature, but also extremely variable among individuals, with an average coefficient of variation (CV) of 9.1 ± 0.3, against a much lesser value of 2.4 ± 0.1 in laboratory flies. Correlations among size traits were also greater in nature (0.96 ± 0.01) than in the laboratory (0.75 ± 0.04).
4. By contrast, sternopleural bristles produced similar results in wild-living and laboratory flies. In nature, mean numbers were only slightly less than in the laboratory and the CVs were almost identical (10.87 ± 0.70 vs 10.80 ± 0.76).
5. Fluctuating asymmetry of sternopleural bristles was also identical in the two kinds of flies, and was not influenced by HEC, indicating a high level of developmental canalisation with respect to HEC.
6. The implications of the results for the problems of field heritability and developmental stability are discussed. 相似文献
2. Two drosophilid species of the Zaprionus genus that recently invaded the Nile delta were investigated, and three metric, size-related traits, and one meristic trait, the sternopleural bristle number, were measured. Data were compared with those of F
3. Body size was smaller in nature, but also extremely variable among individuals, with an average coefficient of variation (CV) of 9.1 ± 0.3, against a much lesser value of 2.4 ± 0.1 in laboratory flies. Correlations among size traits were also greater in nature (0.96 ± 0.01) than in the laboratory (0.75 ± 0.04).
4. By contrast, sternopleural bristles produced similar results in wild-living and laboratory flies. In nature, mean numbers were only slightly less than in the laboratory and the CVs were almost identical (10.87 ± 0.70 vs 10.80 ± 0.76).
5. Fluctuating asymmetry of sternopleural bristles was also identical in the two kinds of flies, and was not influenced by HEC, indicating a high level of developmental canalisation with respect to HEC.
6. The implications of the results for the problems of field heritability and developmental stability are discussed. 相似文献
10.