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401.
The effect of incorporation of 3-43 mol% sterol on the lipid order and bilayer rigidity has been investigated for model membranes of dimyristoylphosphatidylcholine or dipalmitoylphosphatidylcholine. 2H NMR spectra and spin-lattice relaxation rates were measured for macroscopically aligned bilayers. The characteristics of spectra obtained at temperatures between 0-60 °C are interpreted in terms of a two-phase coexistence of the liquid disordered and the liquid ordered phases and the data is found to be in agreement with the phase diagram published by Vist and Davis (Biochemistry 29 (1990), pp. 451-464). The bending modulus of the bilayers was calculated from plots of relaxation rate vs. the square of the order parameter at 44 °C. Clear differences were obtained in the efficiency of the sterols to increase the stiffness of the bilayers. These differences are correlated to the ability of the sterols to induce the liquid ordered phase in binary as well as in ternary systems; the only exception being ergosterol, which was found to be unable to induce lo phases and also had a relatively weak effect on the bilayer stiffness in contrast to earlier reports.  相似文献   
402.
Abstract

There is a growing interest in the tracking of genetic and epigenetic alterations in exhaled breath condensate (EBC) samples. The effects of different procedures on the quality and quantity of DNA in EBC were studied. The results demonstrated that sodium acetate precipitation and oligo (dT) improved the quality of the extracted DNA significantly (p?<?0.01). Also, sodium acetate precipitation, using oligo (dT), incubation at 70?°C and SDS treatment increased the quantity of DNA significantly (p?<?0.01). These results showed the advantages of the chemical and physical manipulations for improving the quality and quantity of the extracted DNA from EBC samples.  相似文献   
403.
The effect of different soybean varieties ( Glycine max 356, M4, M7, M9, Clark, Sahar, JK, BP, Williams, L17, Zane, Gorgan3 and DPX) on the life history and fecundity of the gram pod borer Helicoverpa armigera (Hubner) (synonym Heliothis armigera (Hubner), also known as the American or African bollworm) was determined at 25 ± 1°C, 65 ± 5% r.h. and a light : dark cycle of 16:8 h. The larval period ranged 17.30 to 26.20 days on M7 and L17, respectively. The longest development time was on L17, BP and Sahar (42.71, 40.29 and 39.20 days, respectively) and the shortest was on M7, M9, Williams and Clark (34.21, 36.06, 36.60 and 36.82 days, respectively). The development index of overall immature stages varied from 1.39 to 2.41, with the minimum on L17 and BP and the maximum on M7. The highest daily fecundity and total fecundity (118.92 and 582.70 eggs, respectively) and the lowest (37.88 and 177.10 eggs, respectively) were observed on DPX and 356, respectively. Cluster analysis of the biological parameters of H. armigera on different soybean varieties demonstrated that BP, Sahar and L17 were partially resistant to H. armigera . Knowledge of the extent of susceptibility or resistance of crop varieties and biology of a pest on that crop are fundamental components of integrated pest management (IPM) programs for many crops. Such information can help to detect and monitor pest infestation, variety selection and crop breeding.  相似文献   
404.
Since the new coronavirus known as 2019‐nCoV (severe acute respiratory syndrome coronavirus 2, SARS‐CoV‐2) has widely spread in Wuhan, China, with severe pneumonia, scientists and physicians have made remarkable efforts to use various options such as monoclonal antibodies, peptides, vaccines, small‐molecule drugs and interferon therapies to control, prevent or treatment infections of 2019‐nCoV. However, no vaccine or drug has yet been confirmed to completely treat 2019‐nCoV. In this review, we focus on the use of potential available small‐molecule drug candidates for treating infections caused by 2019‐nCoV.  相似文献   
405.
BackgroundRecent circumstantial evidence suggests increasing number of Iranian patients with cutaneous leishmaniasis (CL) who are unresponsive to meglumine antimoniate (MA), the first line of treatment in Iran. Oral meltifosine was previously reported to be effective in visceral leishmaniasis as well CL. The current study is designed to determine efficacy and safety of oral miltefosine for the treatment of anthroponotic cutaneous leishmaniasis (ACL) cases who were refractory to MA in Iran.Methodology/Principal findingsMiltefosine was orally administered for 27 patients with MA resistant ACL with approved L.tropica infection, at a dosage of ∼2.5 mg/kg daily for 28 days. Patients were evaluated on day 14 and 28, as well as 3, 6 and 12 month post treatment follow up sessions. Laboratory data were performed and repeated at each visit. Data were analyzed using SPSS version 17. Twenty-seven patients including 16 men (59.25%) and 11 women (40.74%) with mean age of 28.56 ± 4.8 (range 3–54 years old) were enrolled. Total number of lesions were 42 (1–4 in each patient). Most of lesions were on face (76.19%). Mean lesions’ induration size was 2.38 ± 0.73 cm at the base-line which significantly decreased to1.31 ± 0.58 cm and 0.61 ±0.49 cm after 14 and 28 days of therapy, respectively (p value <0.05). At 12-months follow-up post treatment, 22 patients had definite/partial cure (81.48%) including 17 definitely cured patients, corresponding to a cure rate of 68% on per protocol analysis, and 62.96% according to intention to treat analysis. Recurrence of lesion was only occurred in one patient (3.70%). Nausea was the most subjective complication during the therapy (33.33%).ConclusionOral miltefosine could be an effective alternative for the treatment of MA-resistant ACL.  相似文献   
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408.
During the purification of human recombinant erythropoietin (rEPO) from host cells, residual DNA may remain in final products. This contamination is a risk factor for patients and may result in the inactivation of some tumor suppressor genes or activation of oncogenes if its concentration is more than the standard defined by WHO. Based on WHO’s criteria, acceptable level of residual DNA in biopharmaceuticals is less than 10–100?pg/dose. In this study, we have designed a sensitive and specific quantitative real-time polymerase chain reaction (PCR) assay for the detection of residual DNA in human rEPO products. All reported sequences of CHO’s GAPDH gene were retrieved from GenBank, and a multiple alignment was performed using Mega 6 software to find conserved regions of the gene. Primers and probe were designed by AlleleID7 software for the highly conserved region. Quantitative real-time PCR showed an R2 value more than 0.99 and the efficiency equal to 101% indicating a highly accurate and efficiency of the reaction, respectively. Based on the standard curve, the limit of detection of the assay was determined to be 10?copies/µL (0.00967?fg/µL). In addition, the inter- and intra-assay of the test were determined to be 1.14% and 0.65%, respectively, which are in acceptable range according to the WHO’s guidelines.  相似文献   
409.
International Journal of Peptide Research and Therapeutics - This study was conducted to evaluate and compare the effects of bioactive peptides derived from sesame meal (BPSM), avilamycin as an...  相似文献   
410.
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