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991.
ABSTRACT

In 2016, the Gerontological Society of America (GSA) developed a research focus on the benefits and potential risks associated with pets among older adults. With the goal of developing a roadmap for human–animal interaction (HAI) research in older people residing in both the community and institutions, GSA convened a workshop of international experts and policy-makers in the fields of aging and HAI. The status of current knowledge was shared on the success factors for healthy aging and the potential challenges (GSA, 2016). Participants considered what roles pets might play in the lives of older adults and their potential to mitigate loneliness, social isolation, and depression, and to enhance mobility and cognitive function. Existing research was shared to provide insights into the ways in which pets can impact older adults and their caregivers and to identify where further research is needed. This paper introduces a series of papers from that meeting, with some additional papers from meeting attendees to expand on the topics covered and provide key perspectives and gaps in information needed, as a foundation for those considering research into this topic. Although HAI/Animal-Assistant Intervention (AAI) research is in its infancy, there is some evidence that pet ownership or animal interaction can have major benefits for many older adults. At the same time, there are some risks to both the pet and the older adult that need to be addressed. Innovative approaches to both AAIs and the ways to overcome challenges are presented in this themed issue of Anthrozoös. Our hope is that the findings from these reviews and reports will stimulate additional work in this area.  相似文献   
992.
KNOX Gene Function in Plant Stem Cell Niches   总被引:2,自引:0,他引:2  
  相似文献   
993.
本文研究了长白落叶松(LarixolgensisHenry)大小孢子叶球的分化及其分布规律.获得如下结果:(1)6月下旬芽鳞形成期终止,7月初进入小孢子叶分化期,7月未至8月上旬小孢子叶分化期结束.8月上旬进入小孢子囊分化期,8月下旬出现造孢细胞,9月中旬形成小孢子母细胞.10月底小孢子母细胞保持在细线期阶段,小孢子叶球进入冬季休眠期.(2)9月初苞片原基开始形成,9月中旬珠鳞原基形成;10月上旬出现胚珠原始体,10月下旬大孢子母细胞形成,10月底大孢子叶球芽进入冬季休眠.(3)小孢子叶球芽主要分布在树冠的中、下部.数量上远远大于大孢子叶球芽的数量,约为大孢子叶球芽的19倍。大孢子叶球芽主要集中分布在树冠中部,而且树冠下部多于树冠上部。  相似文献   
994.
本文用LN及含其活性位点序列的合成肽段cYIGSR和RGDS对小鼠EPC细胞与LN的相互作用机制进行研究。结果表明:合成肽段cYIGSR和RGDS能促进EPC粘附并具协同效应。cYIGSR还能促进EPC扩展与次生TGCs迁移。LNA链上RGD和B_1链上YIGSR两个活性位点协同地参与了LN对EPC的粘附、扩展以及次生TGCs的迁移的促进作用。cY R合用不能完全竞争性抑制EPC与LN的结合,说明还有其他作用位点存在。  相似文献   
995.
An effort has been made for the first time in Asia's largest brackish water lagoon, Chilika, to investigate the spatio-temporal variability in primary productivity (PP), bacterial productivity (BP), bacterial abundance (BA), bacterial respiration (BR) and bacterial growth efficiency (BGE) in relation to partial pressure of CO2 (pCO2) and CO2 air–water flux and the resultant trophic switchover. Annually, PP ranged between 24 and 376 µg C L?1 d?1 with significantly low values throughout the monsoon (MN), caused by light limitation due to inputs of riverine suspended matter. On the contrary, BP and BR ranged from 11.5 to 186.3 µg C L?1 d?1 and from 14.1 to 389.4 µg C L?1 d?1, respectively, with exceptionally higher values during MN. A wide spatial and temporal variation in the lagoon trophic status was apparent from BP/PP (0.05–6.4) and PP/BR (0.10–18.2) ratios. The seasonal shift in net pelagic production from autotrophy to heterotrophy due to terrestrial organic matter inputs via rivers, enhanced the bacterial metabolism during the MN, as evident from the high pCO2 (10,134 µatm) and CO2 air–water flux (714 mm m?2 d?1). Large variability in BGE and BP/PP ratios especially during MN led to high bacteria-mediated carbon fluxes which was evident from significantly high bacterial carbon demand (BCD >100% of PP) during this season. This suggested that the net amount of organic carbon (either dissolved or particulate form) synthesized by primary producers in the lagoon was not sufficient to satisfy the bacterial carbon requirements. Lagoon sustained low to moderate autotrophic–heterotrophic coupling with annual mean BCD of 231% relative to the primary production, which depicted that bacterioplankton are the mainstay of the lagoon biogeochemical cycles and principal players that bring changes in trophic status. Study disclosed that the high CO2 supersaturation and oxygen undersaturation during MN was attributed to the increased heterotrophic respiration (in excess of PP) fuelled by allochthonous organic matter. On a spatial scale, lagoon sectors such as south sector, central sector and outer channel recorded “net autotrophic,” while the northern sector showed “net heterotrophic” throughout the study period.  相似文献   
996.
Quantitative structure–activity relationship (QSAR) analysis uses structural, quantum chemical, and physicochemical features calculated from molecular geometry as explanatory variables predicting physiological activity. Recently, deep learning based on advanced artificial neural networks has demonstrated excellent performance in the discipline of QSAR research. While it has properties of feature representation learning that directly calculate feature values from molecular structure, the use of this potential function is limited in QSAR modeling. The present study applied this function of feature representation learning to QSAR analysis by incorporating 360° images of molecular conformations into deep learning. Accordingly, I successfully constructed a highly versatile identification model for chemical compounds that induce mitochondrial membrane potential disruption with the external validation area under the receiver operating characteristic curve of ≥0.9.  相似文献   
997.
以鹌鹑Emx cDNA片段作为探针,对人胎盘绒毛膜细胞和成人血细胞的基因组DNA进行DNA印迹分析. 结果表明,在人胎盘绒毛膜细胞中Emx基因剂量较成人血细胞高6倍,显示Emx基因在人胎盘绒毛膜细胞基因组中发生了扩增.  相似文献   
998.
Lung cancer is a serious disease that threatens an affected individual's life. Its pathogenesis has not yet to be fully described, thereby impeding the development of effective treatments and preventive measures. “Cancer driver” theory considers that tumor initiation can be associated with a number of specific mutations in genes called cancer driver genes. Four omics levels, namely, (1) methylation, (2) microRNA, (3) mutation, and (4) mRNA levels, are utilized to cluster cancer driver genes. In this study, the known dysfunctional genes of these four levels were used to identify novel driver genes of lung adenocarcinoma, a subtype of lung cancer. These genes could contribute to the initiation and progression of lung adenocarcinoma in at least two levels. First, random walk with restart algorithm was performed on a protein–protein interaction (PPI) network constructed with PPI information in STRING by using known dysfunctional genes as seed nodes for each level, thereby yielding four groups of possible genes. Second, these genes were further evaluated in a test strategy to exclude false positives and select the most important ones. Finally, after conducting an intersection operation in any two groups of genes, we obtained several inferred driver genes that contributed to the initiation of lung adenocarcinoma in at least two omics levels. Several genes from these groups could be confirmed according to recently published studies. The inferred genes reported in this study were also different from those described in a previous study, suggesting that they can be used as essential supplementary data for investigations on the initiation of lung adenocarcinoma. This article is part of a Special Issue entitled: Accelerating Precision Medicine through Genetic and Genomic Big Data Analysis edited by Yudong Cai & Tao Huang.  相似文献   
999.
Homeobox genes, widely distributed among animal and plant kingdoms, play an important role in developmental process. Several homeobox conserved fragments were amplified by PCR and the flanking regions were also obtained by an LM-PCR procedure. Sequencing and Southern analysis showed that they belong to a homeobox gene family of rice. Six homeobox-containing fragments were mapped on the molecular linkage map of rice. They were located on chromosomes 3, 4 and 7 respectively. It is noteworthy that there are 4 homeobox fragments located on rice chromosome 3 and the result is also consistent with the comparative genomics between rice and maize.  相似文献   
1000.
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