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71.
A new subspecies, Jurinea cataonica Boiss. & Hausskn. subsp. mardinensis B. Do?an & A. Duran (Asteraceae), is described and illustrated from Anatolia, Turkey. The subspecies grows on abandoned fields in the Bakirkiri place (C8 Mardin Province) in southeastern Anatolia. It is morphologically similar to J. cataonica subsp. cataonica. Diagnostic morphological characters between these closely similar taxa are discussed and arranged in a key. Ecology and conservation status of the subspecies is also presented. In addition, the geographical distributions of the new subspecies and other related species are given. 相似文献
72.
Precision genetic modifications: a new era in molecular biology and crop improvement 总被引:2,自引:0,他引:2
Recently, the use of programmable DNA-binding proteins such as ZFP/ZFNs, TALE/TALENs and CRISPR/Cas has produced unprecedented advances in gene targeting and genome editing in prokaryotes and eukaryotes. These advances allow researchers to specifically alter genes, reprogram epigenetic marks, generate site-specific deletions and potentially cure diseases. Unlike previous methods, these precision genetic modification techniques (PGMs) are specific, efficient, easy to use and economical. Here we discuss the capabilities and pitfalls of PGMs and highlight the recent, exciting applications of PGMs in molecular biology and crop genetic engineering. Further improvement of the efficiency and precision of PGM techniques will enable researchers to precisely alter gene expression and biological/chemical pathways, probe gene function, modify epigenetic marks and improve crops by increasing yield, quality and tolerance to limiting biotic and abiotic stress conditions. 相似文献
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Alcohol oxidase (AOD) was immobilized in polypyrrole (PPy) and a random copolymer containing 3-methylthienyl methacrylate and p-vinylbenzyloxy poly(ethyleneoxide) matrices. Immobilization of enzyme was performed via entrapment in conducting polymers during electrochemical polymerization of pyrrole through the thiophene moiety of the copolymer. Three different alcohols, namely methanol, ethanol and n-propanol, were used as substrates. Maximum reaction rates, Michaelis–Menten constants, optimum temperature and pH values, operational stabilities and shelf life of the enzyme electrodes were investigated. 相似文献
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Yiginer O Kilicaslan F Aparci M Isilak Z Uz O Bayrak F Eroglu E Uzun M Kardesoglu E Kirilmaz A Cebeci BS 《Indian pacing and electrophysiology journal》2010,10(10):454-463
Aim
We aimed to report the clinical features related to torsades de pointes (TdP) in patients with complete AV block (CAVB).Methods
Patients with CAVB who were admitted to our instituition between January 2007 and January 2010 were retrospectively evaluated in terms of the occurence of TdP. The clinical features were compared in patients with and without TdP using the software of SPSS.Results
Sixty-four patients were determined to have CAVB. Three of them had documented episodes of TdP. All three patients experiencing TdP were females, whereas 48% of the patients with CAVB were females. The mean age of patients with TdP was significantly greater than the mean age of the other patients (85 ±3 vs. 78±7.6, respectively; p<0.05). In our archives, bradycardia exposure time could be determined in only 49 patients without TdP. Among them, just 10 patients had been exposed to bradycardia over 48 hours, whereas all of the 3 patients with TdP had been exposed to bradycardia over 48 hours (p<0.05). Additionally, in two patients with TdP, we demonstrated that QT and QTc prolongation increases as the duration of bradycardia is extended. Furthermore, all patients with TdP had notched T waves in the ECG on the occurrence day of TdP, whereas they did not have any notched T wave in their ECG on the admission day.Conclusion
Among the patients with CAVB, elderly females are more susceptible to development of TdP. Delay in institution of physiological heart rate leads to further QT prolongation and thereby to TdP. Besides QT prolongation, the finding of T wave notching on ECG may also have a predictive value for TdP. 相似文献76.
Bekir Fatih Kahraman Ahmet Altin Sureyya Altin Gulcin Demirel Bayik 《Soil & Sediment Contamination》2017,26(5):486-500
Nutrient enhancement of bioremediation with nitrogen, namely biostimulation, increases process performance. Selection of a proper nitrogen source is critical for bioremediation applications. In this study, the effects of different nitrogen sources on biodegradation of C10–C25 n-alkane compounds in diesel fuel-spiked soil were revealed, and the most appropriate nitrogen source for biodegradation of semi- and non-volatile n-alkanes was investigated. Bioremediation of diesel fuel contaminated soil was monitored in lab-scale reactors for 15 days. Ammonium sulfate, potassium nitrate and urea were used as nitrogen sources. Carbon dioxide and oxygen levels in the reactors were recorded to monitor microbiological activity. Contaminant removal process was investigated by pH, heterotrophic plate count, total petroleum hydrocarbons (TPH) and C10–C25 n-alkane analyses. First-order kinetic constants were calculated via respirometric and contaminant concentration data. According to total C10–C25 n-alkane removal levels and degradation rate constants, ammonium sulfate addition resulted in the most efficient contaminant removal followed by potassium nitrate and urea. Simultaneous degradation of individual n-alkanes was observed for all of the nitrogen sources. Urea addition changed the distribution of individual n-alkane concentrations relative to the pre-experimental concentrations. Nitrogen source type had no differential effect on degradation rates of semi- (C10–C16) and non-volatile (C17–C25) fractions. 相似文献
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Oztürk B Güven M Arpaci F Kömürcü S Ozet A Beyzadeoğlu M 《Biological trace element research》2000,73(2):181-187
Plasma and erythrocyte lipid peroxidation levels of 20 patients with histopathologically confirmed testis cancer and 20 healthy
control individuals were studied between November 1995 and June 1997. The group with testis cancer had a mean age of 24.8±8.2
yr and the control group’s mean age was 28.3±6.9 yr. Stage distribution of the testis cancer cases were 4 of stage A, 10 of
stage B, and 6 of stage C. Blood samples of the patients were drawn after orchiectomy and after 12 h fasting before chemotherapy.
Mean plasma and erythrocyte lipid peroxidation levels were detected to be 14.51±5.30 nmol malondialdehide (MDA)/mL and 9.30±2.06
nmol MDA/g hemoglobin (Hb), respectively, in the testis cancer group, whereas the healthy control group had mean plasma and
erythrocyte lipid peroxidation levels of 10.7±1.82 nmol MDA/mL and 6.18±1.68 nmol MDA/g Hb, respectively. Plasma and erythrocyte
lipid peroxidation values of the testis cancer patients were determined to be statistically significantly higher than that
of the health control group (p<0.001, p<0.001). No significant correlation was determined between plasma, erythrocyte lipid peroxidation levels and tumor markers.
In conclusion, it can be said that an increase in the lipid peroxidation may play a role in the pathogenesis of testis carcinomas
in addition to the other causes. 相似文献
79.
Ascenzi R Ulker B Todd JJ Sowinski DA Schimeneck CR Allen GC Weissinger AK Thompson WF 《Transgenic research》2003,12(3):305-318
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