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101.
实验取经PMSG-hCG处理的未成年雌性大鼠卵巢,用胶原酶-DNA酶消化,制得黄体细胞悬浮液,预孵育1h后加入各种处理因素,继续孵育2h,用放射免疫方法测孵育液中孕酮的量。结果:孵育液中含有高钙或高钾或加入A23187时均可增加黄体细胞基础及hCG诱导的孕酮生成量。相反,减少钙的浓度或加入EGAT或戊脉胺,孕酮生成量则明显减少。酪氨酸抑制hCG刺激的孕酮生成,但对高钙、高钾和A23187增加孕酮的作用没有影响,并对上述三者分别与hCG同时作用所致孕酮生成增加也没有影响。提示:大鼠黄体细胞孕酮生成依赖于细胞内外的钙;细胞内外钙浓度的变化不影响酪氨酸抗hCG致孕酮生成作用;钙与hCG使孕酮增加的作用可能是通过不同机制。 相似文献
102.
刁云程 《生物化学与生物物理进展》1994,21(1):50-55
在综述初级视区胼胝体功能研究的基础上,提出了视网膜双侧投射带的中枢拓扑联系模型,它不但符合一系列生理学和形态学实验的结果,而且解释了胼胝体存在的必要性:它传送的信号补偿了由于存在视网膜双侧投射带而在每侧皮层上所造成的信息损失. 相似文献
103.
Summary An immunocytochemical method was used to differentiate between immunoreactive substances in glandular cells in the corpora cardiaca (CC) and in certain cerebral neurons in 2 insect species, Locusta migratoria migratorioides and Periplaneta americana. The staining properties of antisera raised to different parts of the decapeptide adipokinetic hormone (AKH) were compared and their specificity was determined by preabsorption with AKH and related peptides. Antibodies raised to the N-terminal part of AKH (serum 433) and the central and C-terminal part (serum 241) were found to have different staining properties.In the CC of the locust both antisera show a strong immunoreactivity with glandular cells, we therefore suggest that at least one of the compounds revealed is AKH. Some of the glandular cells in the locust and large numbers of glandular cells in the CC of the cockroach are revealed by the N-terminal specific antiserum. On the other hand, neurons in the central nervous system are revealed only by the C-terminal specific antiserum. The possible identity of the various substances revealed by these two antisera is discussed. 相似文献
104.
P. N. M. Konings H. G. B. Vullings O. J. M. Kok J. H. B. Diederen W. F. Jansen 《Cell and tissue research》1989,258(2):301-308
Summary Neural connections of the corpus cardiacum (CC) in the African locust, Locusta migratoria, were labelled with the fluorescent tracer Lucifer yellow. (1) Unilateral anterograde labelling of the nervus corporis cardiaci I revealed fluorescent fibres in the storage lobe of the CC (CCS). Some fluorescent fibres in the CCS closely approached the ipsilateral border of the glandular lobes of the CC (CCG). Fluorescent fibres also projected into the neuropile of the hypocerebral ganglion via the ipsilateral nervi cardiostomatogastrici I and II, and from there into the oesophageal nerves. (2) Unilateral anterograde labelling of the nervus corporis cardiaci II revealed fluorescent fibres in the CCS and in the ipsilateral CCG. Fluorescent fibres also projected via the ipsilateral nervus corporis allati I into the corpus allatum. (3) Unilateral retrograde labelling of the nervus corporis allati I revealed a distinct fluorescent nerve tract that runs through the CCS and into the nervus corporis cardiaci II. The tract arises from about eight cell bodies in the brain at the rostroventral side of the ipsilateral calyx of the mushroom body. (4) Labelling of the recurrent nerve revealed fluorescent fibres and some fluorescent cell bodies in the hypocerebral ganglion and, via the nervi cardiostomatogastrici I and II, also in the CCS. Fluorescent fibres were also present in the oesophageal nerves. 相似文献
105.
106.
A direct enzyme immunoassay (EIA) for non-specific urinary progesterone (Po) metabolites, utilizing a non-specific monoclonal antibody against pregnanediol-3-glucuronide, was evaluated for the purpose of assessing luteal function in equids. Urinary pregnanediol-3-glucuronide (PdG) and immunoreactive PdG-like conjugate (iPdG) concentrations, indexed by creatinine, were compared to plasma Po concentrations in non-conceptive ovarian cycles through two ovulations in four mares. High-performance liquid chromatography (HPLC) of urine from lutealphase mares and a pregnant zebra revealed an absence of significant concentrations of PdG and the presence of at least three immunoreactive compounds, all of which were more polar than PdG. The concentration of iPdG in the mare ranged from a nadir of approximately 3 ng/mg Cr at the time of ovulation to nearly 400 ng/mg Cr at the mid-luteal-phase peak and paralleled plasma Po concentrations. This non-radiometric assay for iPdG permits the assessment of ovulation, luteal formation and function, and luteolysis in unprocessed urine samples from domestic mares. Data from a single zebra indicate this approach also will permit simplified and non-invasive longitudinal studies of ovarian function among a wide range of Equidae. 相似文献
107.
We previously reported that precocene caused the aphid Myzus persicae to produce male offspring, and further, that daughters (G1) of precocene-treated females also produced males in several temporal patterns. These patterns characteristically exhibited male production early in the reproductive sequence and/or approximately 10 days later. We suggested that ovulation of male eggs might occur at subthreshold juvenile hormone concentrations immediately after precocene treatment (i.e., during the late embryonic stages of the G1 aphids) and again in the last larval instar of the G1 aphids. This paper describes experiments in which G1 aphids were exposed to the JH analog kinoprene prenatally and in the last instar. It was shown that these treatments delayed, eliminated, or interrupted the expected sequences of males, thus providing evidence for the proposed scheme of male determination. The condition of the corpus allatum in G1 adults correlated with the pattern of male production; in continuous male producers the corpus allatum had undergone delayed destruction. A schematic model of the endocrine control of male determination is presented. 相似文献
108.
Kaitlyn Hellner‐Burris Courtney A. Sobieski Valerie R. Gilbert Kimberley A. Phillips 《American journal of primatology》2010,72(6):502-508
The diet of capuchin monkeys consists largely of fruits, but these monkeys commonly prey upon insects and other invertebrates as well as vertebrates such as lizards, birds, and fish. Capturing small fast‐moving prey requires the ability to process complex visuospatial information such as motion detection, shape, and pursuit. Here we report the results of an experimental investigation into whether capuchins display sex differences in prey capture efficiency, and whether these differences are associated with the morphology of regions of the corpus callosum (CC) involved in visuospatial ability. We examined the prey capture behavior of seven capuchin subjects (four female, three male) in the laboratory by providing subjects opportunities to fish. Additionally, we obtained structural magnetic resonance images from these subjects to determine if spatial‐ability was related to CC anatomy. Over 30 fishing trials, we recorded the number of prey capture attempts, success rate in capturing fish, and hand techniques used in these attempts. Males were significantly faster and more successful than females at capturing prey. In addition, males had smaller total CC:brain ratios than females. Males displayed a left hand bias, as well as significant unimanual usage, whereas females displayed no significant preference for hand usage. Individual capture times were correlated with total CC:brain ratio. Taken together, our results suggest a relationship between prey capture efficiency, sex, and the degree of brain lateralization. Am. J. Primatol. 72:502–508, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
109.
Abstract A rapid and simple method has been developed for the simultaneous measurement of juvenile hormone (JH) and JH acid synthesized in vitro by larval corpora allata (CA) of the tobacco hornworm, Manduca sexta. An organic solvent partition of incubation medium efficiently separates JH acid from JH, and a radioimmunoassay which recognizes the two moieties equivalently is then employed to quantify each. The change in the biosynthetic product of the CA from JH to JH acid appears to begin slowly at the time of ecdysis to the last (fifth) larval stadium and is not complete until just prior to wandering (day 4). The inclusion of the JH esterase inhibitor S-benzoyl-O-ethyl phosphoramidothiolate in incubations of corpora allata revealed that the activity of JH esterases from the gland parallels gland activity and that significant hydrolysis of newly synthesized JH by these esterases occurs in incubations of glands taken at the beginnings of the fourth and fifth larval stadia. An allatostatin, which is proposed to inhibit the corpus allatum during the time of the change in its product, inhibits both JH I and JH I acid synthesis. 相似文献
110.
Fang Fu Huan-ling Liu Ru Li Jin Han Xin Yang Pan Min Li Zhen Yong-ling Zhang Gui-e Xie Ting-ying Lei Yan Li Jian Li Dong-zhi Li Can Liao 《Gene》2014
MECP2 duplication results in a well-recognised syndrome in 100% of affected male children; this syndrome is characterised by severe neurodevelopmental disabilities and recurrent infections. However, no sonographic findings have been reported for affected foetuses, and prenatal molecular diagnosis has not been possible for this disease due to lack of prenatal clinical presentation. In this study, we identified a small duplication comprising the MECP2 and L1CAM genes in the Xq28 region in a patient from a family with severe X-linked mental retardation and in a prenatal foetus with brain structural abnormalities. Using high-resolution chromosome microarray analysis (CMA) to screen 108 foetuses with congenital structural abnormalities, we identified additional three foetuses with the MECP2 duplication. Our study indicates that ventriculomegaly, hydrocephalus, agenesis of the corpus callosum, choroid plexus cysts, foetal growth restriction and hydronephrosis might be common ultrasound findings in prenatal foetuses with the MECP2 duplication and provides the first set of prenatal cases with MECP2 duplication, the ultrasonographic phenotype described in these patients will help to recognise the foetuses with possible MECP2 duplication and prompt the appropriate molecular testing. 相似文献