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Tao Tan Jun Wu Chenyang Si Shaoxing Dai Youyue Zhang Nianqin Sun E Zhang Honglian Shao Wei Si Pengpeng Yang Hong Wang Zhenzhen Chen Ran Zhu Yu Kang Reyna Hernandez-Benitez Llanos Martinez Martinez Estrella Nuñez Delicado W. Travis Berggren Juan Carlos Izpisua Belmonte 《Cell》2021,184(8):2020-2032.e14
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Ernest I. Onyishi Piotr Sorokowski Agnieszka Sorokowska R. Nathan Pipitone 《Evolution and human behavior》2012,33(6):771-774
Previous research has demonstrated that having more children decreases marital satisfaction among parents. However, the universality of these findings is limited since the vast majority of the studies have been conducted in Western countries. In the present study, 374 people from the Igbo ethnic group (Nigeria) were assessed for levels of marital satisfaction and the number of children. In contrast to almost all previous findings, we found a positive relationship between the number of children and marital satisfaction among parents. Number of children was the strongest predictor of marital satisfaction even when compared to other variables like wealth and education. Our results suggest that the negative relationship between the number of children and marital satisfaction is not culturally universal and probably only characterizes developed, individualistic Western countries. We discuss our findings from a sociocultural and evolutionary perspective. 相似文献
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Ernest K. Stratton 《The Western journal of medicine》1925,23(10):1301-1303
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A “double-blepharoplast” originates de novo in the spermatogenous cell of Ginkgo biloba L. Initially, the double-blepharoplast consists of two opposing hemispherical bodies comprised of densely staining material. The two blepharoplasts seemingly are pushed apart by the formation of densely packed fibrils which are oriented perpendicular to the distal, rounded edges of the two future blepharoplasts. As the latter move apart, each one develops lightly staining channels which are often organized in a hub and spoke configuration (procentrioles). Microtubules extend from the blepharoplasts as the latter move to their final position in the cell, and centrioles (probasal bodies) become organized at the periphery of each blepharoplast. Two large “osmiophilic globules,” conspicuous entities close to the nucleus of the mature spermatogenous cell, arise de novo. A fibrillogranular body in the cytoplasm, always closely associated with the nucleus, also arises de novo. 相似文献
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Ernest M. Gifford Jr. 《American journal of botany》1960,47(10):834-837
Gifford , Ernest M., Jr . (U. California, Davis.) Incorporation of H3-thymidine into shoot and root apices of Ceratopteris thalictroides. Amer. Jour. Bot 47(10): 834–837. Illus. 1960.—The localization of tritiated thymidine in apical meristems of Ceratopteris thalictroides by the autoradiographic method is described. Intact, floating plants of the fern were placed in 1/2 strength Hoagland's inorganic nutrient solution containing H3-thymidine (10 μc/ml.) for 3 days. The material was killed, dehydrated and embedded in paraffin. Autoradiographic stripping film (AR 10 Kodak) was applied to serial sections. After an appropriate exposure period, the film was developed and the sections with the superimposed film were stained lightly with Harris' hematoxylin. The autoradiographs revealed the presence of the H3-thymidine in nuclei of the large, individualized apical cells of shoots and roots which is proof of DNA synthesis. In no instances were these nuclei unlabeled. If endomitotic reduplication is excluded the results of these studies lend support to the concept that apical cells actually do divide and perhaps at a higher rate than envisioned by other workers. Considerable cytoplasmic labeling occurred and its significance to general problems of DNA synthesis is discussed. 相似文献