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91.
The influence of intercropping with Allium on some insect populations in potato (Solatium tuberosum)
Two field experiments were conducted in West Java, Indonesia to investigate the effects on insect populations in a potato crop of intercropping with Allium cepa or A. sativum. Intercropping reduced populations of Myzus persicae, Aphis gossypii and Empoasca spp. when less than 0.75 m separated the potato plants and Allium spp. Leaf damage to potato by Henosepilachna sparsa was also reduced at this spacing; but populations of Thrips palmi or T. parvispinus were increased. The implications of these trends are noted. 相似文献
92.
93.
外泌体是多泡体与细胞质膜融合后释放的细胞外囊泡.它们携带有源自分泌细胞的功能性蛋白质,脂质和核酸,能够介导细胞间通信,并在生物体的致病过程中发挥重要作用.当前,对外泌体在病毒感染中的作用机制研究,以及外泌体作为病毒感染诊断和治疗的潜在标志物研究仍处于初级阶段.首先阐述了外泌体的组成和生物学发生机制;然后重点阐述了外泌体在病毒感染中的作用机制,尤其是其在免疫调节中的作用;最后探讨了外泌体作为病毒感染诊断和治疗的潜在标志物的可能性及其应用前景. 相似文献
94.
《Bioorganic & medicinal chemistry letters》2020,30(16):127284
Screening a series of 4-anilinoquinolines and 4-anilinoquinazolines enabled identification of potent novel inhibitors of dengue virus (DENV). Preparation of focused 4-anilinoquinoline/quinazoline scaffold arrays led to the identification of a series of high potency 6-substituted bromine and iodine derivatives. The most potent compound 6-iodo-4-((3,4,5-trimethoxyphenyl)amino)quinoline-3-carbonitrile (47) inhibited DENV infection with an EC50 = 79 nM. Crucially, these compounds showed very limited toxicity with CC50 values >10 µM in almost all cases. This new promising series provides an anchor point for further development to optimize compound properties. 相似文献
95.
Piscine novirhabdovirus = Viral Hemorrhagic Septicemia Virus (VHSV) first appeared in the Laurentian Great Lakes with large outbreaks from 2005 to 2006, as a new and novel RNA rhabdovirus subgenogroup (IVb) that killed >30 fish species. Interlude periods punctuated smaller more localized outbreaks in 2007, 2010, and 2017, although some fishes tested positive in the intervals. There have not been reports of outbreaks or positives from 2018, 2019, or 2020. Here, we employ a combined population genetics and phylogenetic approach to evaluate spatial and temporal evolutionary trajectory on its G‐gene sequence variation, in comparison with whole‐genome sequences (11,083 bp) from a subset of 44 individual isolates (including 40 newly sequenced ones). Our results show that IVb (N = 184 individual fish isolates) diversified into 36 G‐gene haplotypes from 2003 to 2017, stemming from two originals (“a” and “b”). G‐gene haplotypes “a” and “b” differed by just one synonymous single‐nucleotide polymorphism (SNP) substitution, remained the most abundant until 2011, then disappeared. Group “a” descendants (14 haplotypes) remained most prevalent in the Upper and Central Great Lakes, with eight (51%) having nonsynonymous substitutions. Group “b” descendants primarily have occurred in the Lower Great Lakes, including 22 haplotypes, of which 15 (68%) contained nonsynonymous changes. Evolutionary patterns of the whole‐genome sequences (which had 34 haplotypes among 44 isolates) appear congruent with those from the G‐gene. Virus populations significantly diverged among the Upper, Central, and Lower Great Lakes, diversifying over time. Spatial divergence was apparent in the overall patterns of nucleotide substitutions, while amino acid changes increased temporally. VHSV‐IVb thus significantly differentiated across its less than two decades in the Great Lakes, accompanied by declining outbreaks and virulence. Continuing diversification likely allowed the virus to persist at low levels in resident fish populations, and may facilitate its potential for further and future spread to new habitats and nonacclimated hosts. 相似文献
96.
Khalil Ur Rehman Shahla Andleeb Saleh Alfarraj Sulaiman Ali Alharbi Adeel Mahmood 《Saudi Journal of Biological Sciences》2021,28(5):3013-3020
This article presents the COVID-19 situation and control measures taken by the Government of Pakistan. Two waves of pandemic are faced globally and similar in the study area. We have investigated the risk management decision in two phases. Primarily, strict lockdown was observed from March 2020 to July 2020 and smart lockdown was enforced from August 2020 to December 2020. It has been studied that during strict lockdown, COVID cases reduced gradually but reopening of institutes and smart lockdown strategy resulted gradual increase in confirmed cases and death rates. During first wave of COVID-19 in Pakistan, a total confirmed number of patients of COVID-19 were 263,496 till 18th of July 2020 with total deaths of 5,568 people and 204,276 recoveries, while total number of COVID-19 patients reached 555,511 till 9th of February 2021 with total deaths of 12,026 people. Province of Sindh was affected badly with total number of 251,434 COVID-19 cases followed by Punjab Province with total number of 161,347 COVID-19 till 9th of February 2020. 相似文献
97.
Massimo Reverberi Mauro Picardo Alessandra Ricelli Emanuela Camera Corrado Fanelli Anna Adele Fabbri 《Free radical research》2013,47(6):833-841
In order to verify the role played by oxidation in the budding of potato tubers (Solanum tuberosum L. cv. Kennebec), the physiological events occurring below bud at 4°C have been studied for a period of 6 months. The low temperature storage induced an increase in the degree of unsaturation and a decrease in the ratio of saturated/unsaturated fatty acids of membrane polar lipids with a subsequent increase of lipid hydroperoxides (LOOH). Cold stress increased both enzymatic antioxidative activities (superoxide dismutase, SOD, E.C.1.15.1.1; catalase, CAT, E.C. 1.11.1.6), and α-tocopherol levels thus protecting membrane's polyunsaturated lipids. Between 0 and 15 days of storage SOD/CAT ratio, α-tocopherol, LOOH levels and the degree of lipid unsaturation showed strong variations. After 30 to 120/150 days the antioxidative system seemed to reach a homeostasis different from that of time 0, accompanied by a constant increase of indole-3-acetic acid (IAA) after 60 days. The antioxidative system, after 150 days, lost its efficiency while LOOH levels were maintained higher than time 0 and IAA concentration was sufficient to allow sprouting. 相似文献
98.
Massimo Reverberi Corrado Fanelli Slaven Zjalic Stefania Briganti Mauro Picardo Alessandra Ricelli 《Free radical research》2013,47(6):637-647
Plant responses to biotic and abiotic stress can be mediated by oxidised products and in this study we analysed the relation among some of them and the growth factor indole-3-acetic acid (IAA). The plant material used was potato tuber sliced below bud and incubated for different lengths of time before analysis. Wounding in potato tuber leads, in a very short time (0–30?min), to the generation of lipid hydroperoxides (LOOH) from polyunsaturated fatty acids (PUFA). These reactive species could cause a subsequent increase of 9 and 13-lipoxygenase (LOX, E.C.1.13.12.12.), analysed by RT-PCR and spectrophotometric assay, LOOH, Jasmonates and IAA all quantified by GC–MS analysis. The activation of 9 and 13-LOX, using different timing, leads to the formation of LOOH with a subsequent generation of jasmonates and IAA as highlighted by the addition on the potato tuber slices of salicylhydroxamic acid (SHAM), an inhibitor of LOX activity. A correlation between jasmonates and IAA resulted by testing their reciprocal influence during wounding in potato tuber. The relationship occurring among each hormone analysed during wounding underlines the fact that the jasmonates level can be regulated in situ and this can suggest a role for these compounds in potato tuber which has been underestimated up to now. 相似文献
99.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-7):767-770
In order to improve the oral bioavailability of 2′-C-methylcytidine, a potent anti-HCV agent, the corresponding 3′-O-L-valinyl ester derivative (NM 283) has been synthesized. Based on its ease of synthesis and its physicochemical properties, NM 283 has emerged as a promising antiviral drug for treatment of chronic HCV infection. 相似文献
100.
Ravi K. Ujjinamatada Yankanagouda S. Agasimundin Peng Zhang Ramachandra S. Hosmane Roman Schuessler Peter Borowski 《Nucleosides, nucleotides & nucleic acids》2013,32(10-12):1775-1788
The attempted synthesis of a ring-expanded guanosine (1) containing the imidazo[4,5-e][1,3]diazepine ring system by condensation of 1-(2′-deoxy-β-D-erythropentofuranosyl)-4-ethoxycarbonylimidazole-5-carbaldehyde (2) with guanidine resulted in the formation of an unexpected product, 1-(2′-deoxy-β-D-erythropentofuranosyl)-5-(2,4-diamino-3,6-dihydro-1,3,5-triazin-6-yl)imidazole-4-carboxamide (7). The structure as well as the pathway of formation of 7 was corroborated by isolation of the intermediate, followed by its conversion to the product. Nucleoside 7 showed promising in vitro anti-helicase activity against the West Nile virus NTPase/ helicase with an IC 50 of 3-10 μg/mL. 相似文献