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41.
Analysis of macromolecular carbohydrates performed by gas liquid chromatography on Gregarina blaberae haemolymph showed the presence of hexoses (galactose, mannose, glucose), methyl-pentose (fucose), and hexosamines (N-acetylgalactosamine, N-acetylglucosamine). No trace of pentose or sialic acid or uronic acid was found. Mannose was the main neutral sugar. A change in the molar ratio of mannose consisting of an enrichment of female haemolymph occurred during larval-adult ecdysis. There was a parallel increase in glycoprotein staining with periodate-fuchsin after cellulose acetate electrophoresis of female haemolymph. 相似文献
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Bilateral electrolytic lesions restricted to the lateral, basolateral and basomedial amygdaloid nuclei in mice produced a lack of avoidance responses towards novel stimuli. While controls showed avoidance and burying reactions to a novel object introduced into their familiar environment, lesioned mice displayed a high number of approach responses and a low level of burying reactions. Furthermore, when given the opportunity to move around freely in simultaneously presented novel and familiar places, control mice at first exhibited avoidance reactions to the novel environment before showing novelty preference. There were no avoidance reactions in lesioned mice. These data are consistent with the hypothesis that amygdala plays a specific role in the regulation of defensive reactions. 相似文献
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Dielectric spectroscopy is a non-invasive contact technique that permits the in vivo measurement of the specific electrical properties of biological tissue induced by an external electrical field. Permittivity, relaxation time and specific conductivity as a function of corneal hydration (wet weight/dry weight) and temperature were measured in 10 porcine corneas. Variation of tissue hydration has a minor influence on the signal, with a significant variation of the signal being detectable only for relatively dry tissue. A much greater influence was found for temperature, in particular on relaxation times. Dielectric spectroscopy provides us with an opportunity to detect structural, in particular temperature-induced, changes in living tissue. In the frequency range investigated, hydration has only a small influence on the dielectric properties of the tissue. 相似文献
46.
The chemiluminescence (CL) of bis(2,4,6‐trichlorophyenyl) oxalate with hydrogen peroxide in the present of cationic surfactant and gold nanoparticles was studied. The CL emission was obviously enhanced in the presence of surfactant at a suitable concentration, with a synergetic catalysis effect exhibited. Different sizes of gold nanoparticles (15 and 50 nm) showed different effects on CL intensity. Mechanisms of the CL reaction and sensitization effect are discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
47.
Jun‐Bo Luan Yong‐Ming Ruan Li Zhang Shu‐Sheng Liu 《Entomologia Experimentalis et Applicata》2008,129(3):316-324
The whitefly Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) is a species complex, and its systematic classification requires controlled crossing experiments among its genetic groups. Accurate information on pre‐copulation intervals, copulation frequencies, and initial frequency of egg fertilization of newly emerged adults is critical for designing procedures for collecting the virgin adults necessary for these experiments. In the literature, considerable variation is reported between B. tabaci populations, with respect to the length of the pre‐copulation interval and the initial frequency of egg fertilization. Here, we used a video‐recording method to observe continuously the copulation behaviour of the Mediterranean/Asia Minor/Africa (B biotype) and the Asia II (ZHJ1 biotype) groups of B. tabaci. We also recorded the initial frequency of egg fertilization, as determined by the sex of the progeny. When adults were caged in female–male pairs on leaves of cotton plants, the earliest copulation events occurred 2–6 h after emergence; at 12 h after emergence 56–84% of the females had copulated at least once, and nearly all (92–100%) had copulated at least once by 36 h after emergence. Both females and males copulated repeatedly. Approximately 80 and 20% of copulation events occurred during the photophase and scotophase, respectively. By 72 h post‐emergence, the females of the B and ZHJ1 biotypes had copulated on average 6.1 and 3.9 times, respectively. When adults were caged in groups on plants 1–13 h after emergence, 30–35% of the eggs deposited during this period were fertilized, and approximately 90% of females were fertilized by the end of the 13 h. Although timing of copulation differed in detail between the two genetic groups, the results demonstrate that B. tabaci adults can start to copulate as early as 2–6 h post‐emergence and the majority of females can become fertilized on the day that they emerge. 相似文献
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49.
Hlne Blanch Lawrence G. Wright Gilles Vergnaud Batrice de Gouyon Valrie Lauthier Lee M. Silver Jean Dausset Howard M. Cann Richard S. Spielman 《Genomics》1992,12(4):826-828
Human homologues of mouse t-complex genes have been cloned and localized physically to chromosome 6p or 6q. TCP1, TCP10, and PLG are human homologues of genes located in the proximal portion of the t-complex on mouse chromosome 17. We present here results of genetic mapping of these human t-complex homologues previously localized to 6q25-q27, 6q21-q27, and 6q26-q27, respectively, by physical techniques. TCP1 and PLG do not recombine with each other and are separated from TCP10 by about 15 cM, while the corresponding mouse genes are no more than 4 cM apart. Genetic mapping with markers well localized cytogenetically places TCP1 and PLG proximal to TCP10 and localizes the latter to the cytogenetic band 6q27. It is likely that the organization of human t-complex homologues on 6q is similar to that of t haplotypes rather than that of wildtype murine chromosome 17. 相似文献
50.
Jean Mariaux 《Systematic parasitology》1991,20(2):109-120
Five taxa included in the cestode genus Anonchotaenia (Cyclophyllidea, Paruterinidae) have been found in various birds from the Ivory Coast (West Africa). The hosts belong to the families Hirundinidae and Corvidae. A. (Paranonchotaenia) prionopos n. sp., parasitic in Prionops plumata, and A. (P.) malaconoti n. sp, parasitic in Malaconotus blanchoti, are placed in a new subgenus named Paranonchotaenia, which is erected for the Anonchotaenia species showing genital ducts passing between the longitudinal excretory stems. A. (P.) prionopos is characterised by a rather short cirrus-pouch, six to seven testes, and an integumental cavity at the distal extremity of the cirrus-pouch in gravid proglottides. A. (P.) malaconoti differs from the former species mainly by the larger cirrus-pouch and a slightly greater number of testes. The other three species are A. longiovata, parasitic in Hirundo semirufa; A. globata, parasitic in Psadiloprocne obscura (the latter two species are recorded from new hosts and new geographical areas); and Anonchotaenia sp., parasitic in Hirundo rustica. It is assumed that the subgenus A. (Anonchotaenia) is rather a parasite of the Passerida and that the subgenus A. (Paranonchotaenia) tends to be parasitic in the Corvida.This paper is a part of the author's thesis.This paper is a part of the author's thesis. 相似文献