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621.
• Introduction
The use of terrestrial LiDAR (light detection and ranging) scanners in forest environments is being studied extensively at present due to the high potential of this technology to acquire three-dimensional data on standing trees rapidly and accurately. This article aims to establish the state-of-the-art in this emerging area. 相似文献622.
粗山羊草高分子量麦谷蛋白新型亚基的筛选和鉴定 总被引:15,自引:0,他引:15
利用SDS -PAGE和Western Blotting分析与鉴定技术 ,从 5 1份粗山羊草中共发现了 2种新型亚基Tx >2和Ty <12 ,被命名为Dx2 1t 和Dy13t;7种亚基组合类型 2 +12、5 +10、2 +10、5 +12、2 1t+10、2 1t+12和 2 +13t,这7种亚基组合的频率分别是 2 7 5 %、2 5 5 %、31 4%、3 9%、2 0 %、2 0 %和 7 8%。已将新型亚基Dx2 1t 和Dy13t的编码基因进行了分子克隆 相似文献
623.
Cloning and sequencing of porcine LH-hCG receptor cDNA: variants lacking transmembrane domain 总被引:22,自引:0,他引:22
H Loosfelt M Misrahi M Atger R Salesse M T Vu Hai-Luu Thi A Jolivet A Guiochon-Mantel S Sar B Jallal J Garnier 《Science (New York, N.Y.)》1989,245(4917):525-528
Complementary DNA clones, encoding the LH-hCG (luteinizing hormone-human choriogonadotropic hormone) receptor were isolated by screening a lambda gt11 library with monoclonal antibodies. The primary structure of the protein was deduced from the DNA sequence analysis; the protein contains 696 amino acids with a putative signal peptide of 27 amino acids. Hydropathy analysis suggests the existence of seven transmembrane domains that show homology with the corresponding regions of other G protein-coupled receptors. Three other types of clones corresponding to shorter proteins were observed, in which the putative transmembrane domain was absent. These probably arose through alternative splicing. RNA blot analysis showed similar patterns in testis and ovary with a major RNA of 4700 nucleotides and several minor species. The messenger RNA was expressed in COS-7 cells, yielding a protein that bound hCG with the same affinity as the testicular receptor. 相似文献
624.
土壤干旱胁迫对白芥光合器官发育及光合速率的影响 总被引:5,自引:1,他引:5
唐道城 《中国油料作物学报》2000,22(1):49-52
利用旱棚盆栽研究了在土壤干旱胁迫下白芥抗旱和不抗旱品系的单叶面积,单株叶面积、出叶速度、叶绿素含量和和净光合速率。结果表明,在土壤干旱胁迫下不同白品系在不同生育时期的单叶面积、单株叶面积、出叶速度及净光合速率都下降,在一定土壤水分范围内,叶绿素含量随土壤水分的下降而增加,抗旱性强的品系受土壤干旱胁迫的影响较小。 相似文献
625.
Pham Nhung Thi Ha Babcsányi Izabella Balling Péter Farsang Andrea 《Journal of Soils and Sediments》2022,22(10):2671-2689
Journal of Soils and Sediments - In agricultural soils, accumulation and bioavailability patterns of potentially toxic elements (PTEs) are key ecological and health risk issues, especially in... 相似文献
626.
Ingrid Nesheim Desmond McNeill K. J. Joy S. Manasi Dang Thi Kim Nhung Maria Manuela Portela Suhas Paranjape 《Irrigation and Drainage Systems》2010,24(3-4):205-221
This paper assesses the implementation of four selected IWRM principles in four very different river basins in Europe and Asia. The four principles relate to all the different aspects of sustainable development—environmental, social, economic and institutional—as well as the factor that is particularly crucial in many countries of the South: implementation capacity. The paper is based on the work performed in the EC-funded STRIVER project, “Strategy and methodology for improved IWRM—An integrated interdisciplinary assessment in four twinning river basins”. The four basins—Tungabhadra and Sesan (in Asia), and Tagus and Glomma (in Europe) exemplify very different problems and challenges with regard to IWRM: different levels of socio-economic development and very varying problems with regard to water quality and availability. The paper shows that the implementation of IWRM is at a fairly early stage in all the four STRIVER basins; and that successful implementation of water resources is dependent not only on the existence of relevant policies, but also the degree to which laws and policies are in fact implemented. 相似文献
627.
Hiep Thi Nguyen Thanh Quang Dang‐Nguyen Tamas Somfai Nguyen Thi Men Nguyen Viet Linh Bui Xuan Nguyen Junko Noguchi Hiroyuki Kaneko Kazuhiro Kikuchi 《Animal Science Journal》2020,91(1)
The aim of this study was to examine whether a morphological approach is efficient for selecting high‐quality porcine embryos produced by in vitro fertilization (IVF) under high polyspermy conditions. Frozen‐thawed Meishan epididymal spermatozoa showing moderate and high polyspermy were subjected to IVF (1 × 105 sperms/ml). Under conditions of moderate polyspermy, 4‐cell embryos selected at 48 hr after IVF (single selection) and 8‐cell embryos selected at 79 hr after IVF from the collected 4‐cell embryos (double selection) showed high developmental competence. Likewise, 4‐ and 8‐cell embryos produced by IVF under high polyspermy conditions also showed high competence for development to blastocysts. However, blastocysts derived from high polyspermy conditions had significantly fewer cells than those produced under moderate polyspermy conditions. Furthermore, the frequency of nuclear and chromosomal abnormalities in 4‐ and 8‐cell embryos produced under conditions of high polyspermy was significantly (p < .05) higher in comparison to moderate polyspermy conditions. These findings suggest that although high polyspermy affects the frequency of nuclear and chromosomal anomalies in porcine IVF embryos, subsequent selection based on morphological features of 4‐ and 8‐cell embryos even under high polyspermy conditions, could be an alternative option for selecting porcine IVF embryos with high development ability. 相似文献
628.
Effects of synbiotic containing Lactobacillus plantarum 7–40 and galactooligosaccharide on the growth performance of white shrimp,Litopenaeus vannamei
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Truong‐Giang Huynh Chia‐Chun Chi Thanh‐Phuong Nguyen Tran‐Thi‐Thanh Hien Tran Ann‐Chang Cheng Chun‐Hung Liu 《Aquaculture Research》2018,49(7):2416-2428
This study aimed to develop a synbiotic combination with probiotic, Lactobacillus plantarum 7–40 and one of three prebiotics, fructooligosaccharide (FOS), galactooligosaccharide (GOS) and mannan oligosaccharide (MOS). The best in vitro growth was observed when probiotic was cultured in the medium containing either FOS or GOS as the sole of carbon source. The analysis of enzyme activity revealed that GOS induced the highest activities of protease and β‐galactosidase of probiotic. Based on the findings, probiotic + GOS were selected as synbiotic to evaluate if it could promote the growth of white shrimp, Litopenaeus vannamei. For this, four diets, including a basal diet with no GOS or probiotic (control), 0.4% GOS (PRE), 108 CFU probiotic kg?1 (PRO) and 0.4% GOS in combination with 108 CFU probiotic kg?1 (SYN), were fed to shrimp for 60 days, and then the growth performance, intestinal microbiota (including total Vibrio counts, VBCs; and lactic acid bacteria, LAB) and digestive enzyme (including protease, leu‐aminopeptidase and β‐galactosidase) were evaluated. The weight gain (WG) of shrimp fed the PRO did not significantly differ from those of control (p > .05). Shrimp fed the SYN had significantly higher WG compared with the other treatments (p < .05). In addition, the SYN‐fed shrimp had significantly higher LAB and protease, leu‐aminopeptidase and β‐galactosidase activity (p < .05). The lowest presumptive Vibrio count (VBC) was also observed in intestines of SYN‐fed shrimp. Therefore, we suggested that Lac. plantarum 7–40+ GOS can be used as a synergistic synbiotic for shrimp culture. 相似文献
629.
将恩诺沙星与皮肤渗透促进剂氮酮按药剂学方法配制的透皮吸收搽剂 ,经皮给药防治哺乳仔猪肠型大肠杆菌病 ,收到了与恩诺沙星注射剂、口服剂同样的效果 .表明透皮吸收制剂在兽医临床上具有广阔的应用前景 . 相似文献
630.
Tamas Somfai Van Khanh Nguyen Huong Thu Thi Vu Huong Le Thi Nguyen Huu Xuan Quan Nguyen Viet Linh Son Le Phan Lan Doan Pham Ngo Thi Kim Cuc Kazuhiro Kikuchi 《Animal Science Journal》2019,90(7):840-848
We report the cryopreservation of oocytes from Ban miniature pigs which are endemic in Vietnam. Immature cumulus‐oocyte complexes were collected from antral follicles of 7–8 mo old female cyclic Ban pigs and vitrified in micro‐drops. Oocyte morphology, lipid content, post‐warming survival, nuclear maturation, and embryo development were compared to those of oocytes from commercially slaughtered Landrace × Large white hybrid pigs. The size of oocytes in the two breeds was similar. However, significantly lower amounts of intracellular lipid were detected in Ban oocytes. There was no difference (p > 0.05) between Ban and Landrace × Large white oocytes in percentages of post‐warming survival (93.1 ± 3.4% vs. 70.7 ± 16.7%, respectively) and nuclear maturation after in vitro maturation (80.4 ± 5.1% vs. 90.0 ± 1.3% respectively). Similarly, cleavage (30.8 ± 7.8% vs. 10.3 ± 6.1%, respectively) and blastocyst development rates (9.4 ± 5.0% vs. 0.79 ± 0.79, respectively) were not different (p > 0.05) between vitrified Ban and Landrace × Large white oocytes after in vitro fertilization and embryo culture. In conclusion, high survival and maturation rates were achieved after vitrification of immature Ban oocytes and their cryo‐tolerance was similar to that of Landrace × Large white oocytes, despite the difference in lipid content. We succeeded to generate reasonable rates of blastocysts from vitrified Ban oocytes by in vitro fertilization. 相似文献