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61.
Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) is one of the most serious pests of greenhouse crops. It is mainly controlled by chemical means, requiring some 10–12 sprays during the average growing season in Turkey. There is growing interest in finding alternatives to pesticides for control of B. tabaci in greenhouse crops because this heavy pesticide usage disrupts biocontrol and leads to rapid build-up of insecticide resistance in the pest. In our study, the control of B. tabaci on greenhouse eggplants was evaluated following releases of the lady beetle Serangium parcesetosum Sicard (Coleoptera: Coccinellidae). In cage experiments, four adults per plant were introduced and, within 3–4 weeks, resulted in 97 and 98% reductions in whitefly populations in 2004 and 2005, respectively. In a large plot experiment, two adults per plant were released only one time. Beetle larvae were observed through 2–9 weeks after release. The density of whitefly in large plot receiving beetle adults showed fluctuations to a level lower than in control plot receiving no beetle in 2004 and 2006. Further study is needed to develop new managing strategies in biological control of B. tabaci with S. parcesetosum in protected culture.  相似文献   
62.
A retrospective study involving 972 twin births was conducted to evaluate the maternal and fetal outcomes of twin pregnancies complicated by single fetal death. The incidence of single fetal death in twin pregnancies after 20 weeks was 3.3%. Preterm birth rates for 37 and 32 gestational weeks were 81.3% and 41.6% respectively. The median interval between the diagnosis of fetal death and the delivery was 11 days (range 1-27 days). Eighteen (56%) infants were delivered by cesarean and 14 (43%) vaginally. Twin-twin transfusion syndrome (TTTS) was the cause of single fetal death in 8 of 32 twin pregnancies (25%). Ten of the surviving co-twins were lost in the neonatal period (31.3%) and half of those neonatal deaths were due to TTTS. TTTS is the major contributor for perinatal mortality in same-sex twins complicated by single fetal death. The death of one twin in utero should not be the only indication for preterm delivery, and in case of severe prematurity with a stable intrauterine environment; expectant management may be advisable until fetal lung maturation ensues.  相似文献   
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Lysinuric protein intolerance is an autosomal recessive metabolic disorder caused by defective transport of the cationic amino acids lysine, arginine and ornithine in the epithelial cells of the basolateral membrane in the small intestine and renal tubules. Mutations in the solute carrier family 7, member 7, SLC7A7, gene cause this multisystemic disease with a variety of clinical symptoms such as hepatosplenomegaly, osteoporosis, hypotonia, developmental delay, pulmonary insufficiency or end-stage renal disease. In the present study, genomic structure of SLC7A7 in six Turkish patients with lysinuric protein intolerance was examined in order to detect disease causing mutations by denaturing high pressure liquid chromatography and direct sequencing. Four novel mutations were identified in SLC7A7: c.223insGTC, p.Val74_Ile75insVal; c.283insTGG, p.Glu94_Thr95insTrp; c.344_347delTTGC, p.Leu115LeufsX53; and c.1099insT, p.Ile367TyrfsX16. Clinical and biochemical findings were evaluated together with these molecular analyses.  相似文献   
65.
This study aimed to compare two different approaches for the purification of enterocin B from Enterococcus faecium strain W3 based on the observation that the bacteriocin was found both in cell associated form and in culture supernatant. The first approach employed ammonium sulfate precipitation, cation-exchange chromatography, and sequential reverse-phase high-performance liquid chromatography. The latter approach exploited a pH-mediated cell adsorption–desorption method to extract cell-bound bacteriocin, and one run of reverse-phase chromatography. The first method resulted in purification of enterocin B with a recovery of 4% of the initial bacteriocin activity found in culture supernatant. MALDI-TOF MS analysis and de novo peptide sequencing of the purified bacteriocin confirmed that the active peptide was enterocin B. The second method achieved the purification of enterocin B with a higher recovery (16%) and enabled us to achieve pure bacteriocin within a shorter period of time by avoiding time consuming purification protocols. The purity and identity of the active peptide were confirmed again by matrix-assisted laser desorption/ionization time-of flight (MALDI-TOF) mass spectrometry (MS) analysis. Although both approaches were satisfactory to obtain a sufficient amount of enterocin B for use in MS and amino acid sequence analysis, the latter was proved to be applicable in large-scale and rapid purification of enterocin B.  相似文献   
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The novel coronavirus (COVID-19, SARS-CoV-2) is a rapidly spreading disease with a high mortality. In this research, the interactions between specific flavonols and the 2019-nCoV receptor binding domain (RBD), transmembrane protease, serine 2 (TMPRSS2), and cathepsins (CatB and CatL) were analyzed. According to the relative binding capacity index (RBCI) calculated based on the free energy of binding and calculated inhibition constants, it was determined that robinin (ROB) and gossypetin (GOS) were the most effective flavonols on all targets. While the binding free energy of ROB with the spike glycoprotein RBD, TMPRSS2, CatB, and CatL were –5.02, –7.57, –10.10, and –6.11 kcal/mol, the values for GOS were –4.67, –5.24, –8.31, and –6.76, respectively. Furthermore, both compounds maintained their stability for at least 170 ns on respective targets in molecular dynamics simulations. The molecular mechanics Poisson–Boltzmann surface area (MM/PBSA) calculations also corroborated these data. Considering Lipinski’s rule of five, ROB and GOS exhibited 3 (MW>500, N or O>10, NH or OH>5), and 1 (NH or OH>5) violations, respectively. Neither ROB nor GOS showed AMES toxicity or hepatotoxicity. The LD50 of these compounds in rats were 2.482 and 2.527 mol/kg, respectively. Therefore, we conclude that these compounds could be considered as alternative therapeutic agents in the treatment of COVID-19. However, the possible inhibitory effects of these compounds on cytochromes (CYPs) should be verified by in vitro or in vivo tests and their adverse effects on cellular energy metabolism should be minimized by performing molecular modifications if necessary.  相似文献   
68.
Micronuclei (MN) in blood lymphocytes were determined in 31 male workers occupationally exposed to lead (Pb), zinc (Zn), and cadmium (Cd) and 20 control workers matched for age and smoking habits. Exposed workers have higher MN mean values than control workers (p<0.01). In exposed workers, blood Pb concentrations were also significantly higher than in control workers (p<0.001), but the mean concentrations of Zn and Cd in the blood were not statistically significant compared to the controls (p>0.05). These results suggest that lead may be genotoxic and the human lymphocyte micronucleus test can be used to assess genotoxic effects that result from occupational exposures.  相似文献   
69.
Journal of Plant Biochemistry and Biotechnology - Wheat is the second important cereal crop worldwide due to nutritional composition and role in meeting daily energy needs. Salinity is an abiotic...  相似文献   
70.
This paper presents new Wide Bandpass Filter (WBPF) and Narrow Bandstop Filter (NBSF) incorporating two microstrip resonators, each resonator is based on 2nd iteration of Hilbert fractal geometry. The type of filter as pass or reject band has been adjusted by coupling gap parameter (d) between Hilbert resonators using a substrate with a dielectric constant of 10.8 and a thickness of 1.27 mm. Numerical simulation results as well as a parametric study of d parameter on filter type and frequency responses are presented and studied. WBPF has designed at resonant frequencies of 2 and 2.2 GHz with a bandwidth of 0.52 GHz, −28 dB return loss and −0.125 dB insertion loss while NBSF has designed for electrical specifications of 2.37 GHz center frequency, 20 MHz rejection bandwidth, −0.1873 dB return loss and 13.746 dB insertion loss. The proposed technique offers a new alternative to construct low-cost high-performance filter devices, suitable for a wide range of wireless communication systems.  相似文献   
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