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141.
142.
Summary Seed set and fruit development in cucumber (Cucumis sativus L.) were studied in relation to female flower receptivity from day — 2 before anthesis to day + 2 after anthesis. The female cucumber flower is protogynous. The pistil was receptive 2 days before anthesis. The iso-electric focusing (IEF) patterns of the stigma/style proteins, were identical from day -5 to day +2. In pollinated flowers in vivo germination and pollen-tube growth in the ovary were affected by pistil age from day -2 to day +2. In addition, differences in sectorial filling in full seeds were observed within the fruits. A negative correlation was observed between the frequency of fertilized ovules in the pedoncular part of the fruit and ovary length at the time of pollination. In the whole fruit, significant differences in the number of full seeds and fruit size at maturity were found, and these were observed to be correlated with the various stages of female flower maturation at pollination. The day -2 and day +2 stages yielded the smallest fruits with few full seeds compared to the day -1, day 0 and day +1 stages, which had the biggest fruits and a large number of full seeds. A strong positive correlation was found between total seed number (including full and empty seeds), fruit length and weight at maturity. All these results suggest that both seed set in the different parts of the fruit and fruit development are controlled by ovular receptivity rather than by stigma/style receptivity.  相似文献   
143.
Summary This communication describes the use of in-vivo and in-vitro autoradiography to map specific platelet-activating factor (PAF) receptors in the rabbit uterus. Specific [3H]PAF uptake was predominantly localized on epithelial, but not on stromal or myometrial cells. Very few silver grains were associated with the luminal epithelial cells in the uterus of the estrous rabbit, primarily because of the non-differentiated state of the epithelium. In the differentiated pregnant uterus, significantly more [3H]PAF was bound to the glandular epithelial cells, with the stromal cells binding consistently significantly less. The highest density of silver grains was observed at the implantation sites on day 7 of pregnancy. There was no apparent difference in [3H]PAF C18:0 uptake between the epithelial cells at the inter-implantation zone on day 7 and on day 6. Bound [3H]PAF was displaceable by lyso-PAF, U66985, CV3988, but not U66982, L652,731, SRI 63,441 or the inactive PAF isomer, oleoyl PAF. Bovine serum albumin (BSA) significantly inhibited tissue uptake of [3H]PAF C18:0. Intraluminally administered [3H]PAF C18:0 and intravenously injected [3H]methylcarbamyl-PAF, a non-metabolizable PAF analog, penetrated the implanted blastocyst and bound to the embryoblast. This event was reproducible in vitro with pre-implantation blastocysts from day-6 pregnant rabbits, which suggests that uterine-derived PAF may translocate into the blastocyst after attachment.  相似文献   
144.
 妊娠期家兎子宫内膜的神经节苷脂(Gls)的含量明显低于动情期的,而中性鞘糖脂(NGSL)的含量则以妊娠中、晚期的最高,动情期最低。鞘糖脂组成变化最显著的是妊娠早期,由动情期到早孕GM_3从28.0%增加到52.7%,CMH.CDH由未测出分别增加到29.2%和21.9%,而糖链复杂的组分GD_3,GTlb和CPH的百分含量则明显减少,到妊娠中、晚期、短糖链组分逐渐减少,而复杂糖链组分渐增。中期妊娠内膜的(GIs)以GD_3为主要组分,占45%,明显高于其它各期。NGSL在妊娠中、晚期CPH增高达70%,与动情期水平相当。结果提示,妊娠期间子宫内膜的鞘糖脂含量与组成均发生明显变化,这些变化可能与子宫功能密切相关。特别是早孕对的变化,推测与子宫内膜和胚泡的识别,粘连特性的获得有关。  相似文献   
145.
146.
Summary In an effort to better understand changes induced by hormonal contraceptives, a group of female baboons were administered Ovral for a period of 9 months. During this time the endometrium was sampled by transcervical uterine biopsy from both the treated animals and from a control group. The biopsies were all obtained between 10 and 14 days of the treatment cycle or the normal menstrual cycle. The endometrial glandular cells from the treated animals exhibited an accelerated maturation compared with the controls. Ultrastructurally this was reflected by increased cell size, numerous long, slender microvilli on the apical membranes, and increased development of the Golgi complex. Differences were also observed in the predominant type of granule seen in the apical cytoplasm. After 3 and 6 months of treatment with Ovral, no significant differences were noted between groups or between animals within a group. However, after 9 months of treatment, the endometrium displayed differences from the earlier experimental groups as well as individual variations. The functional correlates of these observations are discussed and compared to human endometrium.  相似文献   
147.
ABSTRACT In order to verify the physiological functions of male accessory gland (MAG) substances of the blowfly, Lucilia illustris Meigen, the growth and changes in metabolites of male accessory gland with aging, and the effect of male accessory gland extract on mating receptivity of L. illustris were examined. There was not a significant difference in length of MAG with aging, but the width of MAG was grown widely from 0 to 5-days old apparently. Changes in glycogen, total protein and lipid of male accessory gland substances showed same patterns but total protein content was higher than the others. Therefore, male nutrition affected the production of male accessory proteins. During the mating fed unmated male transferred larger amount of protein than that of starved male. When male accessory gland homogenates injected, mating receptivity of gravid female was greatly inhibited comparing to control, suggesting that the accessory gland substances of L. illustris alters female mating receptivity after mating.  相似文献   
148.
The characterization of human uterine smooth muscle cells in culture   总被引:2,自引:0,他引:2  
Primary cultures initiated from normal human uterine endometrium after total enzymatic dissociation contained epithelioid cells and smooth muscle cells. The smooth muscle cells were subsequently isolated by differential trypsinization and grown in culture for 36 +/- 4 generations. Ultrastructural examination of log and post-confluent cultures of cells at low and high population doubling levels revealed characteristics similar to those of published reports on other smooth muscle cells studied in vivo and in vitro. Among the common features present were: (a) abundant bundles of 60--70 A myofilaments; (b) branched mitochondria; (c) stacks of cisternae of rough endoplasmic reticulum; (d) caveolae intracellulares; (e) nexuses. Other features included ovoid nuclei, a well developed Golgi apparatus and abundant free ribosomes. The subcultured cells exhibited features of dedifferentiation in the log phase of growth and at post-confluency. However, the post-confluent cells showed characteristics indicating redifferentiation back towards their in vivo morphology. Smooth muscle cells isolated from endometrial curettings may provide a useful model for biochemical and pharmacological studies of a cell type derived from a hormonal target tissue as the cells "age" in culture.  相似文献   
149.
Summary Endometrium from a group of baboons treated with the oral contraceptive, Enovid E, was studied histologically, histochemically and ultrastructurally, and compared to endometrium from normally cycling animals. All endometria were obtained by transcervical uterine biopsy between 10 and 14 days of the treatment cycle or the normal menstrual cycle. Histologically, no discernible differences between the control and experimental endometria were apparent. While observable differences were not evident between the endometrial alkaline phosphatase and succinate dehydrogenase activities of control and experimental animals, there was an increased acid phosphatase activity in the Enovid E-treated baboon endometrium. Ultra-structurally, the glandular cells of treated animals appeared to be more physiologically advanced than did those from the control endometria. These advances were evident from the prominent Golgi complex, increased development of the endoplasmic reticulum and increases in the size, number and complexity of mitochondria. The functional correlates of these morphological and histochemical observations are discussed and compared to human endometrial studies.The authors wish to express their appreciation to Mrs. Y. Insua and Mrs. M. St. Onge for technical, Mr. G. Kerimian for photographic, and Ms. S. Weaver for secretarial assistanceThis research was supported by NIH contract #NO1-HD-4-2862  相似文献   
150.
During early neonatal development, oxytocin (OT) may influence the expression of adult behavior and physiology. Here we test the prediction that early postnatal exposure to OT or an oxytocin antagonist (OTA) can affect the subsequent expression of sexual receptivity and reproductive success of females. To test this hypothesis, female prairie voles (Microtus ochrogaster) received one of four treatments within 24 h of birth. Three groups received an intraperitoneal injection of OT, OTA, or isotonic saline. A fourth group was handled, but not injected. Around 75 days of age, females were paired with sexually experienced males for 72 h and sexual activity was recorded. Treatment had no effect on the probability of mating. Injection, regardless of treatment, reduced latency to mate compared with handled controls. OT and OTA treatment decreased mating bout frequency compared to saline and handled controls, while OTA treatment increased reproductive success, probability of successfully producing a litter. The results suggest that neonatally OT, both endogenous and exogenous, can affect the expression of adult female reproductive activity and that blocking the effects of endogenous OT during neonatal development can affect female reproductive success. Finally, the results suggest that a number of aspects of reproduction are regulated by OT during the postnatal period, but that the mechanism of action may differ depending upon the reproductive activity.  相似文献   
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