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271.
Rubaiya Rafique Swarna A. K. M. Asaduzzaman Syed Rashel Kabir Nawshin Arfin Sarkar M. A. Kawsar Sultana Rajia Yuki Fujii Yukiko Ogawa Keisuke Hirashima Nanae Kobayashi Masao Yamada Yasuhiro Ozeki Imtiaj Hasan 《Marine drugs》2021,19(7)
In recent years, there has been considerable interest in lectins from marine invertebrates. In this study, the biological activities of a lectin protein isolated from the eggs of Sea hare (Aplysia kurodai) were evaluated. The 40 kDa Aplysia kurodai egg lectin (or AKL-40) binds to D-galacturonic acid and D-galactose sugars similar to previously purified isotypes with various molecular weights (32/30 and 16 kDa). The N-terminal sequence of AKL-40 was similar to other sea hare egg lectins. The lectin was shown to be moderately toxic to brine shrimp nauplii, with an LC50 value of 63.63 µg/mL. It agglutinated Ehrlich ascites carcinoma cells and reduced their growth, up to 58.3% in vivo when injected into Swiss albino mice at a rate of 2 mg/kg/day. The morphology of these cells apparently changed due to AKL-40, while the expression of apoptosis-related genes (p53, Bax, and Bcl-XL) suggested a possible apoptotic pathway of cell death. AKL-40 also inhibited the growth of human erythroleukemia cells, probably via activating the MAPK/ERK pathway, but did not affect human B-lymphoma cells (Raji) or rat basophilic leukemia cells (RBL-1). In vitro, lectin suppressed the growth of Ehrlich ascites carcinoma and U937 cells by 37.9% and 31.8%, respectively. Along with strong antifungal activity against Talaromyces verruculosus, AKL showed antibacterial activity against Staphylococcus aureus, Shigella sonnei, and Bacillus cereus whereas the growth of Escherichia coli was not affected by the lectin. This study explores the antiproliferative and antimicrobial potentials of AKL as well as its involvement in embryo defense of sea hare. 相似文献
272.
Tahir Karasahin Hasan Alkan Fatma Satilmis Sukru Dursun Huseyin Erdem 《Reproduction in domestic animals》2021,56(12):1555-1561
This study aimed to determine the effect of flunixin meglumine treatment during and after the transfer of in vivo produced embryos to Angus (cows) and Holstein (cows and heifers) breeds of cattle on pregnancy rate. Holstein cows were used as donors in the study. A double dose of prostaglandin F2α was administered to the recipient animals for synchronization. Uterine flushing was performed in donors on day 7 after artificial insemination. A total of 295 transferable embryos were obtained. These embryos were transferred to Angus cows (n = 85), Holstein heifers (n = 80) and Holstein cows (n = 130). After the transfer, these animals were divided into three subgroups. The first subgroup (TI) was administered flunixin meglumine during embryo transfer, and the second subgroup (TII) was administered flunixin meglumine both during embryo transfer and on days 8 and 9 after the transfer. The third subgroup (TIII) was not administered anything and it was considered the control group. Pregnancy examination of the recipients was performed on days 30–35 after the transfer using real-time ultrasonography. The pregnancy rates after embryo transfer were found to be 43.52% in Angus cows, 42.5% in Holstein heifers, and 24.61% in Holstein cows (p < .05). When the animals were not classified according to breed, the pregnancy rates in subgroups TI, TII and TIII were found to be 29.29%, 45.10% and 29.79%, respectively (p < .05). In addition, the pregnancy rates were higher in TII and TIII subgroups of Angus cows and Holstein heifers compared to that of Holstein cows (p < .05). As a result, the pregnancy rates obtained after embryo transfer in Angus cows and Holstein heifers were found to be higher than that in Holstein cows. In addition, it was concluded that the administration of flunixin meglumine during and during/after embryo transfer has a positive effect on pregnancy rates in Angus cows and Holstein heifers. 相似文献
273.
为探讨利用三波段植被指数(three-band index, 3BI)对春小麦叶片水分含量(leaf water content, LWC)估算的可行性,在田间尺度上,利用ASD-FieldSpec-3光谱仪测定春小麦抽穗期冠层光谱反射率,采用任意波段组合方法,分别建立两波段植被指数(two-band index, 2BI)包括比值植被指数(RVI)、归一化植被指数(NDVI)、差值植被指数(DVI)及3BI,并对单波段反射率、两波段植被指数和三波段植被指数与春小麦抽穗期LWC之间进行相关性分析,筛选稳定的光谱参数,基于人工神经网络(artificial neural network, ANN)、K近邻(K-nearest neighbors, KNN)和支持向量回归(support vector regression, SVR)等3种机器学习算法,建立有效波段组合运算的抽穗期春小麦LWC估算模型,并利用独立样本对模型精度进行检验和评价。结果表明,单波段反射率、2BI和3BI与春小麦抽穗期LWC之间的相关性均达极显著水平(P<0.01),而相关系数差异较大,绝对值分别为0.23、0.62、0.94,说明组合波段展现了光谱隐含信息,避免有效光谱信息的丢失;估算模型中,春小麦抽穗期以KNN算法和最佳3BI组合变量(3BI-5(1075, 1095, 1085)、3BI-6(1100, 400, 1097))构建的模型拟合度最高(r2=0.83),均方根误差最小(RMSE=2.14%),相对偏差百分比超出了2.0以上(RPD=2.31),说明该模型具有一定的预测能力。由此可见,通过任意波段组合,可明显提高3BI与春小麦LWC的关联度,且基于K近邻算法构建的模型具有较好的稳定性和估算能力。 相似文献
274.
S. Ceccarelli S. Grando M. Singh M. Michael A. Shikho M. Al Issa A. Al Saleh G. Kaleonjy S.M. Al Ghanem A.L. Al Hasan H. Dalla S. Basha T. Basha 《Euphytica》2003,133(2):185-200
Farmer participation is increasingly seen as a key to develop technologies which are more relevant to farmers' communities.
In plant breeding, farmer participation is seen as key to increase the probability of adoption of new varieties. This paper
addresses the issue of selection efficiency in participatory plant breeding by testing the effect of selection environment
and of who did the selection in one cropping season (1997) on the performance of the selected lines in the following cropping
season (1998). Selection environment had a larger effect on response to selection than who did the selection, confirming the
importance of decentralized selection. Selections made by the breeder and the farmers in 1997, differed in 1998 for a number
of traits, but seldom for grain yield. When the difference for grain yield was significant, breeder's selection was more effective
on station, while farmers' selection was more effective in farmers' fields. The results of this study indicate that it is
possible to organize a plant breeding program with the objective of adapting crops to a multitude of both physical and socio-economic
environments: such a breeding program will, at the same time, increase productivity and stability, enhance biodiversity and
produce environmentally friendly cultivars.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
275.
Marker-assisted increase of genetic diversity in a double-low seed quality winter oilseed rape genetic background 总被引:1,自引:0,他引:1
P. Basunanda T. H. Spiller M. Hasan A. Gehringer J. Schondelmaier W. Lühs W. Friedt R. J. Snowdon 《Plant Breeding》2007,126(6):581-587
Generation of novel genetic diversity for maximization of heterosis in hybrid production is a significant goal in winter oilseed rape breeding. Here, we demonstrate that doubled haploid (DH) production using microspore cultivation can simultaneously introgress favourable alleles for double‐low seed quality (low erucic acid and low‐glucosinolate content) into a genetically diverse Brassica napus genetic background. The DH lines were derived from a cross between a double‐low quality winter rapeseed variety and a genetically diverse semisynthetic B. napus line with high erucic acid and high glucosinolates (++ quality). Twenty‐three low‐glucosinolate lines were identified with a genome component of 50–67% derived from the ++ parent. Four of these lines, with a genome component of 50–55% derived from the ++ parent, also contained low erucic acid. Heterosis for seed yield was confirmed in test‐crosses using these genetically diverse lines as pollinator. The results demonstrate the potential of marker‐assisted identification of novel genetic pools for breeding of double‐low quality winter oilseed rape hybrids. 相似文献
276.
Abstract A six hundred hectare township in Saudi Arabia was sprayed by a Micronair equipped helicopter with approximately 11 g of bioresmethrin in 550 ml solvent per hectare, applied in the early morning, on one occasion only, in order to evaluate the technique for fly control. The kill of caged wild flies (Musca domestica nebulo F.) in the open was complete. However, sticky traps and Scudder grill counts indoors indicated only 69% and 72% reduction of fly density. Although coverage by aerial application was found to be accurate, penetration into such areas as covered markets was poor, and therefore the method can only be recommended as an adjunct to ground based operations. 相似文献
277.
Nahar Sharmin Hasan Md. Faruk Sikdar Biswanath Islam Md. Asadul 《Journal of Crop Science and Biotechnology》2021,24(5):521-531
Journal of Crop Science and Biotechnology - The present investigation was carried out to investigate the effects of rhizosphere bacteria on growth and rice yields. Also, isolation and... 相似文献
278.
279.
A rapid, sensitive, and specific radioreceptor assay for the determination of human chorionic gonadotropin and luteinizing hormone in plasma is described. Plasma membranes of bovine corpora lutea of early pregnancy, which bind biologically active labeled human chorionic gonadotropin, have been used as receptor. Pregnancy could be detected by assaying the gonadotropin in plasma samples obtained from day 6 to 8 after conception. 相似文献
280.
Hasan MZ Isaacs ED Shen Z Miller LL Tsutsui K Tohyama T Maekawa S 《Science (New York, N.Y.)》2000,288(5472):1811-1814
The electronic structure of Mott insulators continues to be a major unsolved problem in physics despite more than 50 years of research. Well-developed momentum-resolved spectroscopies such as photoemission or neutron scattering cannot probe the full Mott gap. High-resolution resonant inelastic x-ray scattering revealed dispersive charge excitations across the Mott gap in a high-critical temperature parent cuprate (Ca(2)CuO(2)Cl(2)), shedding light on the anisotropy of the Mott gap. These charge excitations across the Mott gap can be described within the framework of the Hubbard model. 相似文献