共查询到20条相似文献，搜索用时 31 毫秒
1.
Female specific protein: biosynthesis controlled by corpus allatum in Leucophaea maderae 总被引：1，自引：0，他引：1
F Engelmann 《Science (New York, N.Y.)》1969,165(891):407-409
A specific protein is Present in serums of all of Leucophaea maderae that mature eggs but not in serums of males, nymphs of either sex, or females that are reproductively inactive. Ablations, microsurgery and remplantation showed that this protein is produced de novo under the influence of the corpus allatum hormone. This protein, essential for egg maturation, is synthesized in isolated abdimens of allatectomized females treated with 0.08 to 0.12 microgram of the t,t,t-isomer of the authentic juvenile hormone. The crops allatum hormone also stimulates toa similar degree the synthesis of other proteins which appear to be essential for egg maturation as well; these are not specific to females. 相似文献
2.
W Foster 《Science (New York, N.Y.)》1967,158(808):1596-1597
Male Scatophaga stercoraria must prey on other Diptera before they display sexual behavior, develop the accessory cells of their ejaculatory ducts, and achieve full elongation of the testes. The corpus allatum also becomes enlarged after predation and is necessary for the onset of sexual behavior and development of reproductive organs. The complex diet consumed during predation apparently activates the corpus allatum, and the hormone released acts independently on organ growth and sexual behavior. 相似文献
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Tanning in the newly emerged fly is induced by a hormone secreted by neurosecretory cells situated in the pars intercerebralis of the brain. The same hormone is contained in the compound ganglion of the thorax, in concentrations six times as high as in the brain. This hormone is believed to act directly on the eflector organ, and not through the secretion of ecdyson or a corpus allatum hormone; its release is effected through nervous impulses reaching the brain by way of the ventral nervous system a few minutes after the fly has emerged from the puparium. The hormone appears to be different from both the prothoraco-tropic and the gonadotropic hormones. 相似文献
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Ovarian dlevelopmnent, vitellogenesis, andt etnbrvogenesis in recently matedlce fiemnales of tlhe sofi tick Ornithodoros parkeri Coolev were prevented by topical application of the insect antiallatotropin precocene 2. ThCe blockage was relieved by topical application of jtivenile hormonoe. Cancellation of the anti-juvenile hormnone jJects of precocene 2 and the reestablishment of oogenesis (and oviposition in one specimen) bv a naturally occurring insect juvenile hormone argues strongly for a physiological role of juvenile hormone in acarine reproduction. 相似文献
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性腺肽类激素在动物生殖调控中的作用 总被引：1，自引：0，他引：1
阐述了性腺肽类激素抑制素、活化素及卵泡抑素对动物生殖机能的影响及其分泌的调节。抑制素和卵泡抑素均可抑制垂体FSH的活性,从而影响动物的生殖功能。抑制素受内分泌、旁分泌及自分泌作用;卵泡抑素以自分泌方式调节颗粒细胞功能,促进卵泡的黄体化;活化素以自分泌方式调节颗粒细胞的分化,阻止排卵卵泡的黄体化,并有诱导产生和增加FSH受体的功能。 相似文献
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The median neurosecretory cells of the pars intercerebralis of Iphita limbata seem to release two demonstrable components, probably representing allatotropin to the corpus allatum and myotropin to the aortic neurohemal site. 相似文献
8.
Riddiford LM 《Science (New York, N.Y.)》1970,167(3916):287-288
Metamorphosis of the bugs Pyrrhocoris apterus and Oncopeltus fasciatus is blocked by the application of juvenile hormone analogs to the eqgs 4 weeks earlier. One or more supernumerary larval molts occur to form "giant" larvae which routinely die without undergoing netamorphosis. When the corpora allatta were excised at the outset of the fifth larval stage, the entire phenomenon vanished and all individuals underwent normal metamorphosis. The inhibition of metamorphosis can therefoore be attributed to a continuation of the secretion of endogenous juvenile hormone by the corpora allata of mature larvae deried from eggs treated with juvenile hormone. 相似文献
9.
D F White 《Science (New York, N.Y.)》1968,159(811):218-219
Isolated wingless cabbage aphids, Brevicoryne brassicae (L.), produced only wingless young. Aphids isolated from birth all became wingless, whereas over 50 percent of grouped controls developed wings. Isolation caused hyperactivity of the corpus allatum; this hyperactivity may have caused the wingless form. 相似文献
10.
Topical application of juvenile hormone analog induces soldier development in the ant Pheidole bicarinata. Soldier induction takes place if the juvenile hormone analog is present during a period of sensitivity that occurs during the last larval instar. Control of worker dimorphism seems to be accomplished through control of timing of metamorphosis. The smallest size at which metamorphosis can be initiated is shifted upwardfrom 1.2 to 1.7 millimeters by exposure to the juvenile hormone analog during the sensitive period. 相似文献
11.
灭幼脲毒理学研究——Ⅶ.灭幼脲对东方粘虫末龄幼虫保幼激素滴度的影响 总被引：1，自引：0，他引：1
以蜡螟生测法测定了72时龄以内的东方粘虫(Mythimna separata Walkcr)末龄幼虫的保幼激素动态及灭幼脲对其影响,发现在48时龄。保幼激素滴度下降到极低水平时,灭幼脲可使保幼激素滴度堆持在一个高于正常幼虫的水平。不同时龄滴加保幼激素类似物ZR-512,发现幼虫可因施药期不同而对ZR-512产生不同效应,其转换期也是在幼虫发育到48时龄的时候,由此讨论了由于灭幼脲对保幼激素滴度在转换期间不下降到规定阈值,可能干扰了激素序列的调控,导致蜕皮、变态异常的毒理学机制。 相似文献
12.
化学放射法测定蜜蜂保幼激素酯酶活性 总被引：3，自引：0，他引：3
蜜蜂保幼激素(JH)是由蜜蜂咽侧体(CA)合成和分泌的一种氧化物。保幼激素酯酶是对蜜蜂体内呈游离态或结合态的保幼激素进行专化性降解的特异性酯酶。采用放射化学法(RC)测定了西方蜜蜂(Apis mellifera L．)不同日龄工蜂体内保幼激素酯酶(JHE)的活性。结果表明，工蜂体内保幼激素酯酶活性随着日龄的增大而下降。 相似文献
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A new insect juvenile hormone was isolated from developing embryos of the tobacco hornworm moth, Manduca sexta. The new hormone was found with juvenile hormone I and is a 1-carbon homolog of this substance. The assigned structure is methyl (2E,6E,10-cis)-10,11-epoxy-3,7-diethyl-11-methyl-2,6-tridecadienoate, which constitutes a trishomosesquiterpenoid skeleton. This is the first chemical idetification of any juvenile hormone from insect eggs. 相似文献
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Dynamic changes in inhibin messenger RNAs in rat ovarian follicles during the reproductive cycle 总被引：4，自引：0，他引：4
The alterations in morphology and function of the ovarian follicle as it matures, ovulates, and becomes a corpus luteum are dramatic. A variety of steroid and polypeptide hormones influence these processes, and the ovary in turn produces specific hormonal signals for endocrine regulation. One such signal is inhibin, a heterodimeric protein that suppresses the secretion of follicle-stimulating hormone from pituitary gonadotrophs. Rat inhibin complementary DNA probes have been used to examine the levels and distribution of inhibin alpha-and beta A-subunit messenger RNAs in the ovaries of cycling animals. Striking, dynamic changes have been found in inhibin messenger RNA accumulation during the developmental maturation of the ovarian follicle. 相似文献
15.
Systemic activity of a juvenile hormone analog 总被引：1，自引：0，他引：1
The peptidic analog of insect juvenile hormone, ethyl pivaloyl-L-alanyl-p-aminobenzoate with enormous biological activity on the red cotton bug, Dysdercus cingulatus, has pronounced systemic effect in sunflower plants. The compound is absorbed by the plant tissues and appears to be translocated throughout the plant system in active form. There is some evidence that juvenile hormone analogs of other types also have similar systemic effects. The discovery of systemic action should aid in the possible utilization of juvenile hormone analogs in insect control programs. 相似文献
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探索广西地区人工饲养的雌性食蟹猴在少年、青年和中年阶段睾酮和雌二醇分泌情况。使用放射免疫方法分别测定血清中的睾酮、雌二醇含量变化。试验结果表明：广西地区人工饲养的雌性食蟹猴少年组、青年组和中年组间雌二醇分泌的量分别是38.81±21.57 pg/ml、76.09±56.23 pg/ml、64.37±39.48 pg/ml,分泌水平差异极显著（P〈0.01）,其中青年组雌二醇分泌量大于中年组,少年组的含量最少。雌性食蟹猴少年组、青年组和中年组间睾酮的分泌量分别是52.36±24.93 ng/ml,37.95±21.69 ng/ml、80.91±29.19 ng/ml,分泌水平差异极显著（P〈0.01）,其中中年组分泌水平最高,青年组其次,少年组最少。 相似文献
17.
Kataoka H Toschi A Li JP Carney RL Schooley DA Kramer SJ 《Science (New York, N.Y.)》1989,243(4897):1481-1483
A peptide that strongly stimulates the secretion of juvenile hormone from corpora allata in vitro (allatotropin) has been purified from extracts of heads of pharate adult Manduca sexta. The primary structure of this 13-residue peptide has been determined: H-Gly-Phe-Lys-Asn-Val-Glu-Met-Met-Thr-Ala-Arg-Gly-Phe-NH(2). This neurohormone has no sequence similarity with any known neuropeptide from other organisms. Synthetic allatotropin, as well as truncation fragments, including one with the five amino terminal residues deleted, showed in vitro activity indistinguishable from that of native allatotropin. 相似文献
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Juvenile hormone deprivation caused by surgical removal of corpora allata shortly after adult emergence blocked the initiation of biting behavior in Culex. pipiens and Culex quinquefasciatus. Reimplantation of corpora allata or injection of a synthetic juvenile hormone (JH-I) corrected the juvenile hormone deficiency and restored biting behavior. Ovariectomy experiments demonstrated that this behavioral effect of juvenile hormone was independent of ovarian involvement. 相似文献
20.
Juvenile hormone has been implicated in the mediation of several reproduction-related events in adult insects, but had previously been found to play no role in the regulation of sex pheromone production and release behavior ("calling") in moths. In females of the true armyworm moth, Pseudaletia unipuncta, juvenile hormone is shown to be essential to the initiation of both calling behavior and pheromone production. Females without corpora allata, the source of juvenile hormone, do not call and do not produce pheromone, but injection of juvenile hormone into allatectomized females restored these activities. The armyworm's control system has likely evolved in response to the adults' migratory behavior which may necessitate that mating be restricted to the period following migration. 相似文献