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Steroids in latices isolated from 15 Euphorbia species and four other latex-bearing plants were analysed (in terms of their chemotaxonomy) using computerized GC-MS. Steroid patterns divided these plants into six groupings.  相似文献   
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The aim of this study was to examine the frequency of dream recall in Chinese people and to develop nonintrusive procedures to facilitate dream recall. Guidelines for remembering dreams (dream recall instructions) were established based on a review of the existing literature on dream recall and its associated factors. The efficacy of the dream recall experience was explored using this procedure in neurologically healthy individuals. One hundred seventy Chinese participants were included in the study: 100 received the dream recall instructions, and 70 did not. The recall instructions were shown to be effective in triggering dream recall in the participants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Ultrastructure of germ cell development in the human fetal testis   总被引:8,自引:0,他引:8  
Summary Electron-microscopic examination of the human fetal testis between 10 and 20 weeks gestation reveals the presence of two distinct cell types within the tubules: Sertoli cells and germ cells. The latter are distinguished by their spherical shape, smooth nuclear membranes, globular mitochondria and paucity of cytoplasmic organelles. The gonocytes, or primitive germ cells, occur as single cells in the central portions of the tubules. Their chromatin is finely granular and evenly dispersed. Nucleoli are centrally placed and of uniform electron density. Various stages in the migration of gonocytes to the tubular periphery are indicated by the extension of cytoplasmic processes toward the basal lamina. Bands of microtubules are present within the processes. Spermatogonia are arranged in pairs and groups at the tubular periphery. They lack the nucleolar and mitochondrial characteristics of adult spermatogonia. Except for slight changes in chromatin density and nucleolar structure, the fetal spermatogonia retain the ultrastructural characteristics of gonocytes. Intercellular bridges connect adjacent spermatogonia. Degeneration affecting large numbers of germ cells, but primarily gonocytes, begins with nuclear infolding and chromatin condensation and eventually involves both nuclear and cytoplasmic structures. The degenerated cells are removed by phagocytosis by adjacent Sertoli cells. Large phagosomes are present in the cytoplasm of many of the Sertoli cells.Supported by a grant from the Ford Foundation and by General Research Support Grant RR055511 from the National Institutes of Health. Technical assistance was provided by Mrs. Lucy A. Conner.  相似文献   
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The present study aimed to devise a parsimonious instrument for evaluating both the quantitative and qualitative aspects of dream experiences and to quantify Chinese people's dream experiences in ways that facilitated cross-cultural comparisons. The Dream Intensity Inventory was developed and administered to 348 Chinese university students. Individual differences in dream recall frequency were observed, with some participants recalling dreams almost every morning whereas others recalled dreams less than once a month. By contrast, the Chinese participants exhibited less diverse dream awareness frequencies. Multiple dreams in a single night and nightmares were found to be prevalent among the Chinese participants. On the other hand, fewer than half of the participants experienced regularly voluntary control over dream activities and consciousness. The factor analyses of the items in the Dream Intensity Inventory resulted in three readily interpreted factors, which were labeled as the "dream quantity," "altered dream episodes," and "dream vividness" subscales, respectively. When compared with men, women participants had higher frequencies of regular dream experiences including dream awareness, nightmares, and multiple dreams, as measured by the dream quantity subscale. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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MIP-T3 is a human protein found previously to associate with microtubules and the kinesin-interacting neuronal protein DISC1 (Disrupted-in-Schizophrenia 1), but whose cellular function(s) remains unknown. Here we demonstrate that the C. elegans MIP-T3 ortholog DYF-11 is an intraflagellar transport (IFT) protein that plays a critical role in assembling functional kinesin motor-IFT particle complexes. We have cloned a loss of function dyf-11 mutant in which several key components of the IFT machinery, including Kinesin-II, as well as IFT subcomplex A and B proteins, fail to enter ciliary axonemes and/or mislocalize, resulting in compromised ciliary structures and sensory functions, and abnormal lipid accumulation. Analyses in different mutant backgrounds further suggest that DYF-11 functions as a novel component of IFT subcomplex B. Consistent with an evolutionarily conserved cilia-associated role, mammalian MIP-T3 localizes to basal bodies and cilia, and zebrafish mipt3 functions synergistically with the Bardet-Biedl syndrome protein Bbs4 to ensure proper gastrulation, a key cilium- and basal body-dependent developmental process. Our findings therefore implicate MIP-T3 in a previously unknown but critical role in cilium biogenesis and further highlight the emerging role of this organelle in vertebrate development.  相似文献   
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