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排序方式: 共有219条查询结果,搜索用时 234 毫秒
1.
Robert Brus Dalibor Ballian Faruk Bogunić Martin Bobinac Marilena IdžOjtić 《Plant biosystems》2013,147(2):278-285
Abstract In most European countries, the service tree (Sorbus domestica L.) is a rare and threatened species and its conservation has been recognised as a priority. The aim of this study was to asses its morphologic variation in the western and central part of the Balkan Peninsula and in southern Central Europe. Three populations were analysed: one in Serbia, one in Bosnia and Herzegovina and one in Slovenia. In each population 30 trees were selected, and from each tree 30 leaves were collected for morphometric analysis based on nine leaflet morphological traits. Univariate (ANOVA) and multivariate (MANOVA) analysis of variance were used to estimate the variation within- and between populations and a discriminant analysis was performed to examine the structure of the between-population differences. The values of particular morphological traits found in our study did not differ considerably from the values reported elsewhere. The results revealed significant within- and between population variation. Variation within populations was highly significant for all the scored leaf morphological traits, while variation between populations was significant for all the studied traits except for the leaflet length. The discrimination between the three populations was significant. High percentages of correctly classified samples demonstrate good discriminating employability of the analysed leaf morphological traits and indicate differentiation of the analysed populations. 相似文献
2.
Mehmet Ciftci 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):485-489
Inhibitory effects of some drugs on glucose 6-phosphate dehydrogenase from the erythrocytes of rainbow trout (Oncorhynchus mykiss Walbaum, 1792) were investigated. The enzyme was purified 2488-fold in a yield of 76.8% using ammonium sulfate precipitation and 2′,5′-ADP Sepharose 4B affinity gel at 4°C. The drugs pental sodium, MgSO4, vancomycin, metamizol, marcaine, and prilocaine all exhibited inhibitory effects on the enzyme. While MgSO4 (Ki = 12.119 mM), vancomycin (Ki = 1.466 mM) and metamizol (Ki = 0.392 mM) showed competitive inhibition, pental sodium (Ki = 0.748 mM) and marcaine (Ki = 0.0446 mM) displayed noncompetitive inhibition. 相似文献
3.
Kenan Gumustekin Mehmet Ciftci Abdulkadir Coban Sayit Altikat Omer Aktas Mustafa Gul 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):497-502
Effects of nicotine, and nicotine + vitamin E on glucose 6-phosphate dehydrogenase (G-6PD) activity in rat muscle, heart, lungs, testicle, kidney, stomach, brain and liver were investigated in vivo and in vitro on partially purified homogenates. Supplementation period was 3 weeks (n = 8 rats per group): nicotine [0.5 mg/kg/day, intraperitoneal (ip)]; nicotine + vitamin E [75 mg/kg/day, intragastric (ig)]; and control group (receiving only vehicle). The results showed that nicotine (0.5 mg/kg, ip) inhibited G-6PD activity in the lungs, testicle, kidney, stomach and brain by 12.5% (p < 0.001), 48% (p < 0.001), 20.8% (p < 0.001), 13% (p < 0.001) and 23.35% (p < 0.001) respectively, and nicotine had no effects on the muscle, heart and liver G6PD activity. Also, nicotine + vitamin E inhibited G-6PD activity in the testicle, brain, and liver by 32.5% (p < 0.001), 21.5% (p < 0.001), and 16.5% (p < 0.001) respectively, and nicotine + vitamin E activated the muscle, and stomach G-6PD activity by 36% (p < 0.05), and 20% (p < 0.001) respectively. In addition, nicotine + vitamin E did not have any effects on the heart, lungs, and kidney G-6PD activity. In addition, in vitro studies were also carried out to elucidate the effects of nicotine and vitamin E on G-6PD activity, which correlated well with in vivo experimental results in lungs, testicles, kidney, stomach, brain and liver tissues. These results show that vitamin E administration generally restores the inactivation of G-6PD activity due to nicotine administration in various rat tissues in vivo, and also in vitro. 相似文献
4.
Ender Karaca Elif Karakoc-Aydiner Omer Faruk Bayrak Sevgi Keles Serhat Sevli Isil B. Barlan Adnan Yuksel Talal A. Chatila Mustafa Ozen 《Gene》2013
Protein tyrosine kinases (PTKs) play an important role in T cell development and activation. In vitro and in vivo defects, resulting in variable deficiencies in thymic development and in T cell antigen receptor (TCR) signal transduction, in PTKs have been shown. ZAP70, one of those PTKs, is a 70-kDa tyrosine phosphoprotein and associates with the ζ chain and undergoes tyrosine phosphorylation following TCR stimulation. It is expressed in T and natural killer (NK) cells. Several mutations were shown to lead to an autosomal recessive form of severe combined immunodeficiency disease (SCID). 相似文献
5.
In this report we describe the first patient ever found to have azoospermia in association with both exceptional complex chromosomal rearrangements and microdeletions at two translocation breakpoints. A 36-year-old male who had been suffering from male factor infertility was admitted to our clinic. The patient also displayed mild dysmorphia. An analysis of the patient's semen revealed azoospermia. GTG banding revealed the presence of an exceptional complex chromosomal rearrangement involving chromosomes 1, 4, 10 and 14. Using subtelomeric FISH analysis, the patient's karyotype was designated as 46,XY,t(1;10)(q43q44;q21q26.1)(CEB108/T7+,D1S3738-;10PTEL006+,D10S2290+, D1S3738+), ins(14;4) (q31.3;q23q33)(D14S1420+; D4S3359+, D4S2930+). Array-CGH analysis revealed two microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions. We suggest that microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions associated with both an exceptional complex chromosomal rearrangement and the Homo sapiens chromosome 4 open reading frame 37 (C4orf37) gene located at the 4q22.3q23 region might be associated with male factor infertility. 相似文献
6.
The aim of the present study is to determine whether patients with primary spontaneous pneumothorax (PSP) are subject to oxidative stress. For this purpose, we measured the activities of red blood cell superoxide dismutase, which is an antioxidant enzyme, and the level of plasma malondialdehyde, which is one of the lipid peroxidation markers, in a group of patients with PSP. The study was carried out with 16 patients with PSP and 24 healthy individuals. The two groups were similar to each other in terms of sex, age and smoking attitudes. Erythrocyte superoxide dismutase activity was found to be significantly lower in patients with PSP than in the control group (p < 0.01). The plasma malondialdehyde levels were significantly high in patients with PSP (p < 0.01). Our results suggest that oxidative stress may contribute to the pathogenesis of PSP. 相似文献
7.
Single-cell protein production from ram horn hydrolysate by bacteria 总被引:23,自引:0,他引:23
The alcoholysis (transesterification) of the refined cotton seed oil of Turkish origin with primary and secondary alcohols was investigated in the presence of an immobilized enzyme from Candida antarctica, commercially called Novozym 435 in a solvent-free medium. The optimum conditions of the methanolysis were as follows: 30% enzyme based on oil weight; oil/alcohol molar ratio 1:4; temperature: 50 degrees C and reaction time: 7 h. Maximum methyl esters (ME) yield was 91.5%. At the same conditions cotton seed oil was converted with short-chain primary and secondary alcohols to its corresponding esters with conversions between 72% and 94%. Our results indicated that alcoholysis products of cotton seed oil could be used as valuable intermediates in oleochemistry. 相似文献
8.
Glucose 6-phosphate dehydrogenase (G6PD) was purified from chicken erythrocytes, and some characteristics of the enzyme were investigated. The purification procedure was composed of three steps: hemolysate preparation, ammonium sulfate precipitation, and 2',5'-ADP Sepharose 4B affinity gel chromatography. Thanks to the three consecutive procedures, the enzyme, having the specific activity of 20.862 EU/mg proteins, was purified with a yield of 54.68% and 9,150-fold. Optimal pH, stable pH, optimal temperature, molecular weight, and KM and Vmax values for NADP+ and glucose 6- phosphate (G6-P) were also determined for the enzyme. In addition, Ki values and the type of inhibition were determined by means of Line-Weaver-Burk graphs obtained for such inhibitors as ATP, ADP, NADH, and NADPH. 相似文献
9.
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