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11.
Summary In order to obtain markers for the Y chromosome ofSilene latifolia, we pooled equal weights of leaf tissue from 18 female siblings into one sample and repeated the process with 18 male siblings. Pooling was intended to provide a common genetic background for each sample, leaving the absence or presence of the Y chromosome as the primary difference between the two samples. DNA was extracted from each sample and subjected to polymerase chain reaction (PCR) amplification with arbitrary 10 bp primers. Four of 60 primers used gave an amplification with the male DNA not found among those from the female DNA. Each of these was subsequently shown to provide a reliable marker for the Y chromosome. 相似文献
12.
B. S. Hansson J. N. C. Van der Pers H. -E. Högberg E. Hedenström O. Anderbrant J. Löfqvist 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(5):533-538
Summary Electroantennographic and single sensillum recordings were performed on male pine sawfly, Neodiprion sertifer, antennae. Responses to the sex pheromone component (2S, 3S, 7S)- 3,7-dimethyl-2-pentadecenyl (diprionyl) acetate (SSS:OAc), to the behavioral inhibitor (2S, 3R, 7R)-diprionyl acetate (SRR:OAc), to the six other enantiomers of diprionyl acetate, and to the biosynthetic precursor diprionol were recorded. Responses to trans-perillenal, a monoterpene identified in female gland extracts and to (2S, 3S, 7S)-diprionyl propionate (SSS:OPr), a field attractant for N. sertifer and some related sawfly species were also recorded.EAG recordings demonstrated a high antennal sensitivity to SSS:OAc and to SSS:OPr. A somewhat lower response was elicited by SRR:OAc.Single sensillum recordings revealed 8–12 different cells firing in each sensillum, corresponding to the number of cells observed in earlier morphological investigations. Out of these cells all, except one, responded to SSS:OAc and to SSS:OPr. No differences in the response to the two components could be observed. The largest amplitude cell in each sensillum was specifically tuned to the behavioral antagonist, SRR:OAc. The pheromone perception system encountered in male pine sawflies thus differs clearly from that observed in moths.Abbreviation
EAG
electroantennogram
-
OAc
acetate
-
OPr
propionate 相似文献
13.
Ludwik K. Malendowicz 《Cell and tissue research》1974,151(4):525-536
Summary Adrenal glands of adult female rats are heavier than the glands of corresponding male rats. Postpubertal orchiectomy increases the adrenal weight, an effect restored by testosterone replacement. Under the same conditions ovariectomy of 8 weeks duration does not change the adrenal weight while estradiol replacement enhances the relative adrenal weight.Karyometric studies have shown that nuclei in the female zona fasciculata cells are larger (app. 18%) than those of the male. Similar but only slight differences (2%) were observed in the zona reticularis. Orchiectomy results in enlargement of cell nuclei within all zones of the adrenal cortex; testosterone replacement has the opposite effect. Ovariectomy of 8 weeks duration slightly enhances the volume of nuclei of the zona glomerulosa cells, has no effect on the nuclei of the zona fasciculata and reduces the volume of nuclei in the zona reticularis. Estradiol replacement reduces the volume of nuclei of the zona glomerulosa cells but increases nuclear volume in the zona fasciculata and in the zona reticularis.Thus testosterone has an inhibitory effect on the adrenal cortex of the rat while the physiologic effect of estradiol on the morphology of this gland, particularly on the zona fasciculata cells is rather dubious.The author wishes to thank Mrs. B. Westerska and Miss K. Siejak for excellent technical assistance.This research was supported in part by a grant from the Zoological Committee, 2nd Department, Polish Academy of Sciences.This paper is dedicated to the memory of late Kazimierz Mietkiewski, M.D., Ph.D. whose encouragements and suggestions were most stimulating for my work. 相似文献
14.
Food preferences and nematode parasitism were studied in natural populations of mycophagousDrosophila in and near Sapporo, northern Japan. Species which preferred fresh mushrooms showed species-specific responses toPleurotus mushrooms:D. pirka bred only onPleurotus cornucopiae, D. trivitata onP. cornucopiae andP. ostreatus, D. trilineata on these twoPleurotus mushrooms and some other mushrooms, whileD. sexvittata bred on a wide variety of mushrooms but seldom onPleurotus mushrooms. Species which preferred decayed mushrooms (D. quadrivittata, D. histrioides, D. testacea and species of thequinaria species-group) showed host preferences different from those of the above species. The rate of parasitism by nematodes was
generally higher in species which prefer decayed mushrooms than in species which prefer fresh mushrooms. Among species which
prefer fresh mushrooms, onlyD. trilineata was parasitized frequently by nematodes. It was not clear what factors determine the rate of parasitism in these mycophagousDrosophila.
D. pirka, D. trivittata andD. trilineata passed through three or four generations per year and entered reproductive diapause in early September in and near Sapporo.
Bionomics of Drosophilidae (Diptera) in Hokkaido, IX. 相似文献
15.
Natal dispersal in relation to population density and sex ratio in the field vole,Microtus agrestis 总被引:1,自引:0,他引:1
Summary In a sample of 240 juvenile field voles 8% of the males and 22% of the females reached sexual maturity within their natal home range. Among individuals retrapped as adults, 58% of males and 23% of females had dispersed, i.e. had moved more than one home range diameter. The mean distance moved for males (58.5 m) exceeded that for females (28.6 m). Male movement distances were negatively associated with total density, and with density of adult females, but not with male density. Female movements were not related to population density. There were no relation between sex ratio and distance moved. The distribution of distances moved for both males and females fit a geometrical distribution, suggesting the importance of competitive processes. 相似文献
16.
Angela Meder 《Primates; journal of primatology》1990,31(1):51-63
Studies of the behaviour of 26 (12 males and 14 females) captive infant and juvenile lowland gorillas showed clear sex differences.
Females showed greater interest in young infants and were more active in nest building as well as in solitary and social grooming.
Males were more active in locomotive, dominance, and aggressive behaviour and in social play. Hand-rearing further increased
aggression. Males were more aggressive when they lived with only one partner, and they rose in rank even above older females,
a pattern that has not been observed in naturally reared gorillas. 相似文献
17.
Donna K. Stafford Garrett W. Milliken Jeannette P. Ward 《Primates; journal of primatology》1990,31(3):407-414
Lateralized hand use in gibbons was assessed for both food reaching and leading limb in brachiation. Sex and age effects were
found in hand preference for food reaching. Adult females were all very strongly right hand preferent, whereas adult males
had no across group consistent preference. Within the female group there was a strong correlation between age and strength
of right handedness. When compared in terms of absolute strength of hand preference, females were found to be more strongly
lateralized than males. Leading limb preference in brachiation was scored into vocal and non-vocal categories. Three subjects
had a shift in preferred leading limb from the non-vocal brachiation condition to the vocal brachiation condition. This shift
may be influenced by the arousal effects of species typical vocalization. The results of this study underline the importance
of consideration of such factors as sex and age when interpreting behavioral lateralization data. The exploration of laterality
in many different response measures is important to the achievement of a complete understanding of behavioral lateralization
in primates. 相似文献
18.
Occlusal morphology of permanent dentitions in 29 men with a 47,XXY chromosome complement (Klinefelter syndrome) was determined from dental casts. The results showed that a relatively frequent occlusal anomaly was mesial molar occlusion. Incisal open bite was also more common than in controls. Based on the present and previous observations of occlusal anomalies in various sex chromosome anomaly groups and normal controls, it is suggested that the presence of the Y chromosome in the genome is at least as important as the X chromosome for the development of harmonious occlusal morphology. The tendency towards sexual dimorphism in occlusal phenotype might result from a differential effect of the X and Y chromosomes on cellular activity which leads to different growth patterns. 相似文献
19.
K. Thórarinsson 《BioControl》1990,35(1):107-118
Measurements of body length of cottony-cushion scales,Icerya purchasi Maskell, are presented. Although length increased markedly with developmental stage, the length distributions of successive
stages were found to overlap, making length an imperfect indicator of stage andvice versa. The likelihood of parasitism by the fly,Cryptochaetum iceryae (Williston), was found to increase with increasing scale size when scales of different sizes were concurrently made available
to the parasites under field conditions. Also, parasite loads (no. of parasites per parasitized host) were found to increase
with host size. The size ofC. iceryae pupae was found to depend on the developmental stage of the scale host in which pupation took place — the more developed
(larger) the host, the larger the pupa. This result suggests that parasite growth is food limited in the smaller hosts, and
that therefore its apparent preference for larger hosts is to the parasite's advantage.
相似文献
20.
J.C. Hervé F. Pluciennik F. Verrecchia B. Bastide B. Delage M. Joffre J. Délèze 《The Journal of membrane biology》1996,149(3):179-187
17β-estradiol propionate was found to reduce the gap junctional communication in a concentration range similar to that of
testosterone propionate, in primary cultures of rat Sertoli cells and cardiac myocytes. Uncoupling was reversible on washing
out and occurred without concomitant rise in the intracellular calcium concentration.
Esterification was a prerequisite for the activity of extracellularly applied steroid compounds (for example, testosterone
was ineffective even at external concentrations up to 100 μm, whereas its intracellular application at 1 μm totally interrupted intercellular communication), but their uncoupling efficiency did not depend on the nature of the ester
chain nor on its position on the steroid nucleus. The derivatives of two other androgen hormones (derivatives of the androstane
nucleus) were also efficient as junctional uncouplers. Among five steroid molecules belonging to the pregnane family, only
one (pregnanediol diacetate) interrupted the junctional communication. Neither cholic acid nor cholesteryl acetate or ouabain
showed this effect. Altogether, no correlation with the presence or position of double bonds nor with the trans- or cis-fusion of the A and B rings could be recognized.
These results suggest that this reversible, nondeleterious uncoupling effect of steroids is independent of the shape of the
molecules and is more probably related to their size and liposolubility, that condition their insertion into the lipid bilayer.
Their incorporation into the membrane could disturb the activity of the membrane proteins by a physical mechanism.
Received: 10 April 1995/Revised: 27 October 1995 相似文献