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101.
The riboflavin kinase in Methanocaldococcus jannaschii has been identified as the product of the MJ0056 gene. Recombinant expression of the MJ0056 gene in Escherichia coli led to a large increase in the amount of flavin mononucleotide (FMN) in the E. coli cell extract. The unexpected features of the purified recombinant enzyme were its use of CTP as the phosphoryl donor and the absence of a requirement for added metal ion to catalyze the formation of FMN. Identification of this riboflavin kinase fills another gap in the archaeal flavin biosynthetic pathway. Some divalent metals were found to be potent inhibitors of the reaction. The enzyme represents a unique CTP-dependent family of kinases. 相似文献
102.
Hasan Hosseinzadeh Saeid Nasrollanejad Zahra Dordiani Vahid Jamshidnezhad 《Archives Of Phytopathology And Plant Protection》2013,46(16):1879-1883
Sharka disease is one of the most damaging diseases of fruit trees in the world, which is caused by Plum pox virus (PPV) that belongs to the genus Potyvirus in the family Potyviridae. Each year, this virus decreases the yield and causes substantial economic damages to its host plants worldwide. This virus is quarantined in Iran but in recent years, suspicious symptoms of the disease were observed in different grown areas, such as Golestan province. During 2010, 420 samples with mosaic, chlorosis, necrosis, ring pattern, blotches, etc. symptoms were collected from the gardens in Golestan province that included 100 samples from plum, 100 from peach and 240 from nectarine. These samples were evaluated using a double-antibody sandwich-ELISA (DAS-ELISA) method and a polyclonal antibody. The results of this survey indicated that among the total of 420 samples, none of them showed positive reaction in DAS-ELISA test. 相似文献
103.
Malaka Ameratunga Khashayar Asadi Xihui Lin Marzena Walkiewicz Carmel Murone Simon Knight Paul Mitchell Paul Boutros Thomas John 《PloS one》2016,11(4)
IntroductionImmune checkpoint inhibition has shifted treatment paradigms in non-small cell lung cancer (NSCLC). Conflicting results have been reported regarding the immune infiltrate and programmed death-ligand 1 (PD-L1) as a prognostic marker. We correlated the immune infiltrate and PD-L1 expression with clinicopathologic characteristics in a cohort of resected NSCLC.MethodsA tissue microarray was constructed using triplicate cores from consecutive resected NSCLC. Immunohistochemistry was performed for CD8, FOXP3 and PD-L1. Strong PD-L1 expression was predefined as greater than 50% tumor cell positivity. Matched nodal samples were assessed for concordance of PD-L1 expression.ResultsOf 522 patients, 346 were node-negative (N0), 72 N1 and 109 N2; 265 were adenocarcinomas (AC), 182 squamous cell cancers (SCC) and 75 other. Strong PD-L1 expression was found in 24% cases. In the overall cohort, PD-L1 expression was not associated with survival. In patients with N2 disease, strong PD-L1 expression was associated with significantly improved disease-free (DFS) and overall survival (OS) in multivariate analysis (HR 0.49, 95%CI 0.36–0.94, p = 0.031; HR 0.46, 95%CI 0.26–0.80, p = 0.006). In this resected cohort only 5% harboured EGFR mutations, whereas 19% harboured KRAS and 23% other. KRAS mutated tumors were more likely to highly express PD-L1 compared to EGFR (22% vs 3%). A stromal CD8 infiltrate was associated with significantly improved DFS in SCC (HR 0.70, 95%CI 0.50–0.97, p = 0.034), but not AC, whereas FOXP3 was not prognostic. Matched nodal specimens (N = 53) were highly concordant for PD-L1 expression (89%).ConclusionPD-L1 expression was not prognostic in the overall cohort. PD-L1 expression in primary tumor and matched nodal specimens were highly concordant. The observed survival benefit in N2 disease requires confirmation. 相似文献
104.
Summary Leaf disc transformation-regeneration technique was applied to the drought tolerant wild relative of cultivated tomato,Lycopersicon chilense, using a plasmid construct which contained the coding sequences of neomycin phosphotransferase (NPTII) and chloramphenicol acetyltransferase (CAT) genes. The two genotypes used, LA2747 and LA1930, showed a distinct difference in their aptitude to transformation; a higher success rate was obtained for the first genotype in every stage of the process. Shoots were formed on the regeneration medium containing 100 g/ml kanamycin through direct or indirect organogenesis. Root formation became only possible when the concentration of kanamycin was reduced to 50 g/ml. Expression of chloramphenicol acetyltransferase gene was observed in all of the kanamycin-screened plants after they matured; the activity of the gene was absent or low in some of the young plants. The presence of the CAT gene in transgenic plants was further confirmed by Southern blot analysis. Although transgenic plants grew to maturity, they did not produce fruit, owing to the self incompatibility ofL. chilense.
Abbreviations BAP
6-benzylaminopurine
- CAT
chloramphenicol acetyltransferase
- 2,4-D
2,4-dichlorophenoxyacetic acid
- IAA
indole-3-acetic acid
- LB
Luria Broth
- EDTA
ethylenediamine-tetraacetic acid 相似文献
105.
Bahmani Bahareh Amini-bayat Zahra Ranjbar Mohammad Mehdi Bakhtiari Nahid Zarnani Amir-Hassan 《International journal of peptide research and therapeutics》2021,27(1):365-378
International Journal of Peptide Research and Therapeutics - Cervical cancer is the second most common leading cause of women's death due to cancer worldwide, about 528,000 patients’... 相似文献
106.
Asadi Nematollah Kheradmand Arash Gholami Mohammad Reza 《International journal of peptide research and therapeutics》2019,25(2):719-726
International Journal of Peptide Research and Therapeutics - Varicocele, abnormal dilatation of the spermatic vein, is one of the most common andrological disease found during a male physical... 相似文献
107.
Bevacizumab Antibody Affinity Maturation to Improve Ovarian Cancer Immunotherapy: In Silico Approach
Eyvazi Shirin Payandeh Zahra Khalili Saeed Sefid Fatemeh Ouladsahebmadarek Elaheh 《International journal of peptide research and therapeutics》2019,25(4):1417-1430
International Journal of Peptide Research and Therapeutics - Ovarian cancer is one of the most lethal gynecologic cancers. The high mortality rate is due to lack of early symptoms and developing... 相似文献
108.
Asghari Mohammad Shaghaghi Zahra Farzipour Soghra Ghasemi Arash Hosseinimehr Seyed Jalal 《Molecular biology reports》2019,46(6):5909-5917
Molecular Biology Reports - Olanzapine (OLA), is prescribed as an anti-psychotic medicine in schizophrenia patients. In this study, the protective effect of OLA against genotoxicity and... 相似文献
109.
Kourosh Bamdad Zahra Adel Masoomeh Esmaeili 《Journal of cellular biochemistry》2019,120(6):10572-10575
Exposure to electromagnetic fields is considered as a potential hazard for biological systems. The objective of our investigation is the study of probable consequences of radiofrequency electromagnetic fields from Wi-Fi router devices on the short-term memory, and attention's levels. A population consisting of 312 female college students (14 to 17 years old) was elected by cluster random sampling. Teenagers were divided into two groups of control group (Wi-Fi nonusers; n = 138), and experiment group (Wi-Fi users; n = 174). Both groups have been examined using short-term memory tests; selective attention, and also divided attention tests. According to the results, there was no significant difference between using Wi-Fi router devices on levels of selective attentions and short-term memory of the sample students with the control group. However, analyses revealed that there is a significant correlation between the use of Wi-Fi routers and declining levels of divided attentions. Our investigation has demonstrated the adverse consequences of 2.4-2.48 GHz radiofrequency electromagnetic fields of Wi-Fi router devices on divided attention levels of female university students that should be mentioned as a technological risk factor and taken into account by healthcare organizations. 相似文献
110.
Human Immunodeficiency Virus Type 1 (HIV-1) Quasispecies at the Sites of Mycobacterium tuberculosis Infection Contribute to Systemic HIV-1 Heterogeneity 下载免费PDF全文