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排序方式: 共有348条查询结果,搜索用时 31 毫秒
101.
Radan Elvis Matias de Oliveira Giovanna Almeida Santoro Augusto Carlos da Bôaviagem Freire Fernanda Löffler Niemeyer Attademo Stella Almeida Lima Aline da Costa Bomfim Ana Bernadete Lima Fragoso Flávio José de Lima Silva Simone Almeida Gavilan Moacir Franco de Oliveira 《Anatomia, histologia, embryologia》2020,49(1):25-30
The aortic arrangement is an important structure associated with the maintenance of homeostasis. Based on this information, this study was conducted to describe the collateral arteries of the aortic arch of Antillean manatee and define the standard model for the species. Three specimens, an adult male, adult female and a male neonate, all strandings on the coast of the state of Rio Grande do Norte, Brazil, were used. The study was performed in the Laboratory of Morphophysiology of Vertebrates of the Federal University of Rio Grande do Norte, where in situ photographs were taken to demonstrate their topography. Subsequently, their hearts were removed and fixed in 10% formaldehyde and after 72 hr were dissected and analysed, obtaining schematic drawings and photographs of the vascular arrangement. The aortic arch was represented by three collateral arteries identified as the brachiocephalic trunk, left common carotid artery and left subclavian artery. This arrangement was similar to that found for other sirenians, and yet, for other mammals like hooded seal, murine, margarita island capuchin, black-handed tamarin, Mongolian gerbil and human. The morphological similarity presented in this study with different species of mammals, including humans, may contribute valuable information from an evolutionary point of view. 相似文献
102.
Collateral arteries of the aortic arch of the red-rumped agouti (Dasyprocta leporina Linnaeus, 1758)
Radan Elvis Matias de Oliveira Herson da Silva Costa Hélio Noberto de Araújo Júnior Igor Renno Guimarães Lopes Paulo Mateus Alves Lopes João Vitor de Oliveira Gurgel Moacir Franco de Oliveira 《Anatomia, histologia, embryologia》2020,49(3):417-424
Detailed knowledge of the arterial system is an important prerequisite when interpreting experimental data in research, as well as in the diagnosis of cardiovascular disease using imaging techniques such as Doppler echocardiography and contrast radiography. Thus, considering the importance of the aortic arrangement, the objective of this study was to describe the collateral arteries of the aortic arch of agoutis in order to establish the standard model, and therefore contribute to studies involving research related to heart disease, and produce information for a more accurate diagnosis in complementary imaging examinations. In this study, 14 adult animals were used, comprising eight males and six females. The vascular system was washed with 0.9% aqueous saline solution and perfused with Neoprene 450 latex coloured with yellow or red pigment, which was subsequently dissected and analysed. One male animal was used for the digital contrast radiography technique perfused with a liquid barium sulphate solution (Bariogel®) (1 g/ml) and Neoprene 450 latex, both diluted 1/3. The aortic arch of the agouti presented with only the brachiocephalic trunk as collateral branch in all the animals studied. Thus, agouti falls into type 1 for mammalian aortic arch vascular arrangements. 相似文献
103.
华山松嫩枝与硬枝嫁接技术研究 总被引:3,自引:1,他引:3
影响华山松嫁接成败的因子较多,但主要因子有:嫁接方法,砧木年龄,保护辊的使用,嫁接部位,操作技术,气象因子,嫁接时间等,试验结果表明,较好的嫁接方法为髓心形成层贴接法(硬枝接)和切接法(嫩枝接);嫁接时间硬枝接以2-3月,嫩枝接以3-5月为宜,砧木年龄为3-5a;硬枝接嫁接部位取砧木中部效果好,嫩枝接使用保护罩效果好,阴雨天气嫁接成活率经晴天高,通过试验,筛选出华山松嫁接的最佳条件组合,且使嫁接时间由原仅限于2-3月延长到5月份。 相似文献
104.
【目的】研究花铃期水分亏缺对不同部位果枝棉铃大小(直径、长度、体积)、各组分干重(铃壳、纤维、棉籽)和产量的变化,以及水分亏缺处理与棉铃指标的关系,为机采棉花铃期供水不足时提供参考滴灌量。【方法】以新陆早50号和新陆早73号为材料,花铃期设3个滴灌量:2 450 m3/hm2(CK)、2 050 m3/hm2(D1)、1 650 m3/hm2(D2),于花后17 d开始,每隔7 d分别取第2、第5和第7果枝的棉铃,共取5次,测定棉铃大小及各组分干重。【结果】2个品种不同部位果枝棉铃长度、直径和体积均在花后24 d达到最大值。在花后45 d,D1和D2处理中上部果枝棉铃直径与对照差异明显,新陆早50号中部和上部果枝棉铃直径分别降低2.92%~4%和2.21%~5.35%;新陆早73号分别降低2.66%~6.38%和2.77%~8.69%。2个品种棉铃各组分干重棉籽 > 纤维 > 铃壳,铃壳、棉纤维及棉籽重分别在花后24、38和38 d达到最大值。在花后45 d,2个品种D1和D2处理中上部果枝棉籽重与对照差异明显,新陆早50号中部和上部果枝棉籽重分别下降8.9%~20.71%和11.53%~20.73%;新陆早73号分别下降8.96%~16.24%和10.21%~17.06%。单株籽棉产量与棉籽重呈极显著的正相关。2个品种D2处理各部位果枝减产明显,新陆早50号下部、中部和上部果枝籽棉产量分别下降12.5%、13.48%和15.67%;新陆早73号分别下降12.69%、11.9%和18.21%。【结论】中上部果枝棉铃直径是影响棉铃干重的重要因素。水分亏缺不利于棉纤维和棉籽发育,中上部果枝棉籽受影响较大。D1处理与对照各部位果枝成铃数和籽棉产量差异不显著,2 050 m3/hm2(D1)为应对花铃期供水不足时滴灌量。 相似文献
105.
Modeling jack pine branch characteristics in Eastern Canada 总被引:2,自引:0,他引:2
Eric Beaulieu Robert SchneiderFrank Berninger Chhun-Huor UngD. Edwin Swift 《Forest Ecology and Management》2011,262(9):1748-1757
A total of 83 trees were sampled in three regions of Eastern Canada in order to model branch characteristics (number of branches per annual shoot, branch insertion angle and diameter) using linear mixed-effects models. Differences in branch characteristics according to branch type (pseudo-whorl at annual shoot apical end (PWA) versus pseudo-whorl between shoot apical ends (PWB)) were also studied. The number of both PWA and PWB branches are proportional to annual shoot length, whereas the number of PWB branches also decreases with tree age. Insertion angle was mainly driven by annual shoot number from apex (branch age). The diameter models showed the most complexity with branch vertical position and tree size (DBH and total height) among the statistically significant variables. Region and plot random effects were minimal compared with tree and annual shoot levels. Tree-level random effects were significant for every model and might be a symptom of genetic control over the number of branches and, to a small extent, branch diameter. Interaction between insertion angle and diameter is relatively strong because all the models using them as independent variables (except for the model of insertion angle for PWB branches) showed better fit statistics. These results lead us to believe that tree-, annual shoot- and branch-level variables should be further explored in order to better understand branch dynamics. 相似文献
106.
光合作用增效剂在高粱上的应用 总被引:6,自引:5,他引:1
为探索"叶之缘"光合作用增效剂对高粱生长发育及产量的影响,运用随机区组设计法,设计了光合作用增效剂3个剂量、3个喷施时期的试验研究。结果表明:该药剂对高粱产量有显著影响,拔节期喷施450~600 g/hm2光合作用增效剂能显著增加一级枝梗数、穗长及穗粒质量,从而提高产量。 相似文献
107.
108.
柑的早果性、丰产性与其树形结构有密切的联系。本文通过对瑞金、新干等产区实地调查,取得丰富的数据,对碰柑树冠生长量、夏梢生长量、高宽比、分枝数及裙枝数等多项因子与柑早期产量的相关性进行通径分析,揭示其线性关系,得出柑早结丰产的形成与其早期多项生产指标本质的内在联系。 相似文献
109.
110.