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131.
Ordookhani A Padyab M Goldasteh A Mirmiran P Richter J Azizi F 《Chronobiology international》2010,27(9-10):1854-1869
Seasonal aggregation and the monthly rate of neonatal transient hyperthyrotropinemia (THT) were assessed. From November 1998 to April 2005, neonates of gestational age ≥37 wks, birth weight 2500-4000?g, birth length 45-55 cm, and 1st min Apgar score >3, who had thyrotropin (TSH) ≥20 mU/L in their cord dried-blood specimen, but without congenital hypothyroidism, were enrolled in the study. The recall rate equals the rate of THT occurrence in this study. Of 47,945 neonates, 555 had THT (recall rate: 1.2%). The aggregated seasonal recall rate (recall for further assessment to rule out congenital hypothyroidism) was significantly higher in winter (January, February, and March) than the other seasons (p < .0001). Winter had higher recall rate in each year as compared to other seasons, but the overall rate of recalls decreased in 2001 and 2002. Excluding the first 6 months (due to erratic variations), the remaining 72 months revealed a relatively sinusoidal pattern in monthly recall rates; indeed, there was an initial 11-month high recall rates (1.7%), followed by a 33-month decrease (0.7%), a 19-month increase (1.9%), and a final 9-month decrease (0.8%). The recall rate of each of these time intervals was significantly different from that of the next time interval (p < .0001). The monthly recall rates were best fitted to cubic curve estimation and then autoregressive integrated moving average (ARIMA) (0, 1, 1) models. THT occurs significantly more in winter than in other seasons, and this suggests a possible role for time-varying factor(s) contributing to its seasonal preponderance. 相似文献
132.
Mohsin Sayed Mohammad Hasanuzzaman Mirza Nahar Kamrun Hossain Md. Shahadat Bhuyan M. H. M. Borhannuddin Parvin Khursheda Fujita Masayuki 《Physiology and Molecular Biology of Plants》2020,26(6):1139-1154
Physiology and Molecular Biology of Plants - Fungicides are widely used for controlling fungi in crop plants. However, their roles in conferring abiotic stress tolerance are still elusive. In this... 相似文献
133.
Mehdi D. Esraili Fariba Mohammadian-Sabet Parvin Esmailpour Mohammad Solimannejad 《Journal of molecular modeling》2013,19(12):5625-5632
This article analyzes the substitution effects on cooperativity between fluorin-centered halogen bonds in NCF?·?·?·?NCF?·?·?·?NCX and CNF?·?·?·?CNF?·?·?·?CNX complexes, where X?=?H, F, Cl, CN, OH, and NH2. These effects are investigated theoretically in terms of geometric and energetic features of the complexes, which are computed by ab initio methods. The topological analysis, based on the quantum theory of atoms in molecules (QTAIM), is used to characterize the interactions and analyze their enhancement with varying electron density at bond critical points. It is found that the complexes with electron-donating groups exhibit a strong cooperativity, while a much weaker cooperativity occurs in the NCF?·?·?·?NCF?·?·?·?NCCN and CNF?·?·?·?CNF?·?·?·?CNCN trimers. An excellent correlation is found between the cooperative energy in the ternary complexes and the calculated three-body interaction energies. The energy decomposition analysis (EDA) indicates that the electrostatic and dispersion effects play a main role in the cooperativity of fluorine-centered halogen bonding. Figure
Structure of NCF···NCF···NCX and CNF···CNF···CNX complexes 相似文献
134.
Parvin Ramak Shahrokh Kazempour Osaloo Hassan Ebrahimzadeh Mozafar Sharifi Mehrdad Behmanesh 《Journal of plant physiology》2013
Carvacrol is a major component of Satureja khuzistanica Jamzad (≤90%) that has significant antimicrobial and antioxidant properties. Considering the specific capabilities of S. khuzistanica to produce highly pure carvacrol, this plant is an important potential source of carvacrol that could address the abundant consumption and increasing demand for this monoterpene in current world markets. This research was performed to better understand the process of biosynthesis and accumulation of carvacrol in S. khuzistanica. Tests were performed on shoot cultures of S. khuzistanica in Linsmaier-Skoog (LS) medium treated with different concentrations of fosmidomycin (an inhibitor of the non-mevalonate pathway) and mevinolin (an inhibitor of the mevalonate pathway) for 21 days at the following concentrations: 0, 10, 25, 50, 75 and 100 μM. The present study demonstrated that the MEP pathway is the major pathway that provides IPP for the biosynthesis of carvacrol, and the expression and activity levels of the DXR enzyme have a critical effect on carvacrol biosynthesis. Surprisingly, Mevinolin at concentrations of 75 and 100 μM increased the carvacrol content and the DXR activity and gene expression in S. khuzistanica plantlets. 相似文献
135.
Fatemeh Hosseininaveh Parvin Razavi Tabatabaei Ali Darvishzadeh Faezeh Bagheri 《Archives Of Phytopathology And Plant Protection》2013,46(14):1704-1715
Pistachio fruit hull borer, Arimania komaroffi Ragonot (Lep.: Pyralidae), is one the most important pests of pistachio in Iran. The larvae spin web as well as bore into young fruits, and the infested fruits fall off the trees. The second-generation adult moths appear in August and September, and their offspring feed on the fruit hull. Results indicated the presence of α-amylase, α-glucosidase, β-glucosidase, α-galactosidase, β-galactosidase and some proteases in the digestive tract of the pest. Highest activities of α-amylase, α-glucosidase, β-glucosidase, α-galactosidase and β-galactosidase were at pH 10, 7, 7, 6 and pH 6, respectively. Highest activities of trypsin, chymotrypsin and elastase of larval midgut were at pH 11. Zymogram analysis of α-amylase, α-glucosidase, β-glucosidase, tryptic, chymotryptic and elastase using native-PAGE revealed 1, 1, 2, 3, 3 and 2 bands of activity respectively, in A. komaroffi. One band was disappeared in the presence of the inhibitor TLCK, but no further inhibition by the inhibitors TPCK was observed. The results can be of help for designing new strategies for controlling the pistachio fruit hull borer based on natural proteases and carbohydrase inhibitors. 相似文献
136.
Various lipopeptides produced by Bacillus subtilis were examined for their ability to modify the surface hydrophobicity of two substrata, stainless steel (SS) and Teflon. These modifications were evaluated by water contact angle measurements. The effects depended on the lipopeptide, its concentration, and the tested substratum. Treatment of SS with different concentrations of surfactin S1 showed an increase of the hydrophobicity between 1 and 100 mg l?1. On the same substratum, fengycin increased hydrophobicity up to its critical micelle concentration (6.25 mg l?1). With higher concentrations of fengycin, hydrophobicity decreased. Surfactin, mycosubtilin, and iturin A decreased hydrophobicity on Teflon. The different effects of these three families of lipopeptides were related to their structural differences. A good correlation was shown between hydrophobicity modifications of surfaces and the attachment of B. cereus 98/4 spores. Enhancement in the hydrophobicity of the surfaces increased the number of adhering spores. 相似文献
137.
Javad Hashemi Evelyn Morin Parvin Mousavi Keyvan Hashtrudi-Zaad 《Journal of electromyography and kinesiology》2013,23(2):416-424
In this paper, a calibration method to compensate for changes in SEMG amplitude with joint angle is introduced. Calibration factors were derived from constant amplitude surface electromyogram (SEMG) recordings from the biceps brachii (during elbow flexion) and the triceps brachii (during elbow extension) across seven elbow joint angles. SEMG data were then recorded from the elbow flexors (biceps brachii and brachioradialis) and extensors (triceps brachii) during isometric, constant force flexion and extension contractions at the same joint angles. The resulting force at the wrist was measured. The fast orthogonal search method was used to find a mapping between the system inputs – estimated SEMG amplitudes and joint angle – and the system output – measured force, for both calibrated and non-calibrated SEMG data. Models developed with calibrated data yielded a statistically significant improvement in force estimation compared to models developed with non-calibrated data, suggesting that the calibration method can compensate for changes in the SEMG–force relationship with changing joint angle. It was also found that the number of non-linear, joint angle-dependent terms used in the SEMG–force model was reduced with calibration. Additionally, initial inter-session analysis performed for four subjects suggests that calibration values can be used for subsequent recording sessions, and different output force levels. 相似文献
138.
Ye F Lemieux H Hoppel CL Hanson RW Hakimi P Croniger CM Puchowicz M Anderson VE Fujioka H Stavnezer E 《The Journal of biological chemistry》2011,286(46):40013-40024
139.
Farsad F Karbassi A Monavari SM Mortazavi MS Farshchi P 《Biological trace element research》2011,143(3):1828-1842
This study aims to investigate the pollution rate of heavy metals on the western seaboard of Bandarabbas in southeast Iran
using a new pollution index. The bulk of the analysis was conducted on sediments, followed by selection of a few samples to
perform experiments on chemical partitioning studies as well as biological accessibility. On this basis, the proportions of
natural and anthropogenic elements were calculated. Finally, with regard to chemical separation results, the pollution rate
was calculated based on Muller's geo-chemical index, enrichment factor, pollution index, and a new "Risk" index. Chemical
separation showed the anthropogenic origin of elements are as follows: Ni(27.5%) > Zn(6.5%) > Pb(2%) > Al (0.2%). The newly
developed pollution index is indicative of "low environmental pollution "for Ni. 相似文献
140.
Sima Seifi Farzaneh Pouya Mahsa Rahmani Mehrane Mehramiz Azam Rastgar-Moghadam Masoumeh Gharib Farzad Rahmani Soodabeh Shahidsales Seyed Mahdi Hassanian Majid Khazaei Parisa Dadjoo Seyede Sara Parvin Yeganeh yazdinezhad Seyed Mohammad Reza Parizadeh Gordon A. Ferns Mehdi Fathi Amir Avan 《Journal of cellular physiology》2020,235(6):5141-5145
There is a growing body of data reporting the association of genetic alterations in chromosome 9P21 with the risk of developing cancer. In the current study, we studied the association of a genetic variant in CDKN2A/B, rs1333049, with the risk of developing breast cancer. A total of 339 participants with and without breast cancer entered to the study. Genotyping was done by the TaqMan real-time polymerase chain reaction (RT-PCR) method and gene expression analysis was ran by RT-PCR. Our data showed that the minor allele homozygote in the total population was 10%, whereas for heterozygote was 38%. The dominant genetic model demonstrated that individuals with breast cancer had advanced TNM classification. Moreover, the logistic regression revealed that individuals who had CC/CG genotypes might have an enhanced risk of developing breast cancer when compared to the holders of GG genotype (e.g., OR = 2.8; 95% CI,1.4–5.4; p = .001), after regulated for confounders; age and body mass index. Furthermore, our analysis showed that the CDKN2A/B gene was downregulated in patients (p < .001). We showed a meaningful relationship of CDKN2A/B with the risk of breast cancer, cancer, showing the importance of studies in great sample size and several centers for studying the value of the marker as a risk classification in the management of patients with breast cancer. 相似文献