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51.
Fecal samples from 20 Caucasian tree squirrels, Sciurus anomalus (Gmelin, 1778) Güldenstaedt, 1785, were collected in Turkey during February and March, 2004, and all 20 were infected with a single species of coccidia, Eimeria serbica. Sporulated oocysts are ellipsoidal, 27.5 x 17.5 (21-34 x 15-20) with a length:width ratio (L/W) of 1.6 (1.4-1.8); they lack a micropyle and oocyst residuum, but 0-2 polar granules may be present. Sporocysts are ellipsoidal, 11.9 x 6.9 (10.5-14 x 6-7.5) with a L/W of 1.7 (1.5-2.1); a Stieda body and sporocyst residuum are present.  相似文献   
52.
Immobilization of tyrosinase in polysiloxane/polypyrrole copolymer matrices   总被引:1,自引:0,他引:1  
Immobilization of tyrosinase in conducting copolymer matrices of pyrrole functionalized polydimethylsiloxane/polypyrrole (PDMS/PPy) was achieved by electrochemical polymerization. The polysiloxane/polypyrrole/tyrosinase electrode was constructed by the entrapment of enzyme in conducting matrices during electrochemical copolymerization. Maximum reaction rate (V(max)) and Michaelis-Menten constant (K(m)) were investigated for immobilized enzyme. Enzyme electrodes were prepared in two different electrolyte/solvent systems. The effect of supporting electrolytes, p-toluene sulfonic acid and sodium dodecyl sulfate on the enzyme activity and film morphology were determined. Temperature and pH optimization, operational stability and shelf-life of enzyme electrodes were also examined. Phenolic contents of green and black tea were determined by using enzyme electrodes.  相似文献   
53.
Sternbergia fischeriana is an endangered geophyte and therefore in vitro micropropagation of this plant will have great importance for germplasm conservation and commercial production. Bulb scale and immature embryo explants of S. fischeriana were cultured on different nutrient media supplemented with various concentrations of plant growth regulators. Immature embryos produced higher number of bulblets than bulb scales. Large numbers of bulblets were regenerated (over 80 bulblets/explants) from immature embryos on Murashige and Skoog (MS) medium supplemented with 4 mg l–1 6-benzylaminopurine (BA) and 0.25 mg l–1 -naphthaleneacetic (NAA) or 2 mg l–12,4-dichlorophenoxyacetic acid (2,4-D) after 14 months of culture initiation. Regenerated bulblets were kept at 5 °C for 5 weeks and then transplanted to a potting mixture.  相似文献   
54.
The aim of this study was to investigate a possible relation between power performance of the Wingate test (WT) and isometric leg strength (ILS) and explosive leg strength (ELS) characteristics in young men and women with different physical fitness levels. A total of 166 subjects, including 98 young men and 68 young women, were included in the study. The subjects were divided into a regular exercise group and a sedentary group. The physical and body mass index characteristics of the subjects were not different, and they had not taken part in the directed jumping. When the regular exercise and sedentary groups were considered together with men, women, and total population groups, no significant correlation existed between WT anaerobic fatigue index and ILS and ELS (p > 0.05), but significant positive correlations existed among peak power, peak power per weight, mean power, mean power per weight, and WT power, which were recorded in 5-second intervals (p < 0.001). Although the 5-second WT parameters were significantly correlated with ILS and ELS for the first 15-second period, this correlation was more pronounced for the last 15 seconds for all groups (p < 0.01). As a result, this study indicated that regular physical activity has a positive significant relation on WT power, ILS, and ELS in both sedentary men and women and those engaged in regular sports activities.  相似文献   
55.
A new affinity gel for purification of carbonic anhydrase isozymes was prepared using EUPERGIT C-250L derivatized with p-aminobenzenesulfonamide, an inhibitor of carbonic anhydrase. The binding capacity of the affinity gel was determined at different temperatures, pH values, elution buffers, and ionic strengths. Human carbonic anhydrase isozymes (HCA I and HCA II) and bovine carbonic anhydrase (BCA) were purified in high yields from erythrocytes.  相似文献   
56.
57.
The efficacy of low‐toxicity chemicals as possible alternatives to synthetic fungicides for the control of Uromyces appendiculatus and Puccinia triticina was evaluated. A preliminary selection of food additives was performed through in vitro and in vivo preliminary screenings. The ED50 and minimum inhibition concentration (MIC) values showed that most of the food additives used in this study were more toxic to U. appendiculatus than to P. triticina. Acetic acid, potassium carbonate, sodium carbonate and sodium molybdate were the food additives that were more toxic to the urediniospores of P. triticina. Selected compounds and concentrations were tested on bean and wheat plants grown in pots under controlled conditions. Acetic acid, ammonium bicarbonate, potassium acetate, potassium benzoate, potassium bicarbonate, potassium carbonate, sodium acetate and sodium citrate at 0.03, 0.09, 0.03, 0.006, 0.012, 0.012, 0.03 and 0.03 m , respectively, significantly reduced the disease severity of U. appendiculatus without causing any injury to bean leaves. Ammonium bicarbonate, potassium bicarbonate, sodium bicarbonate and sodium citrate at 0.12, 0.03, 0.12 and 0.03 m , respectively, were the most effective in reducing the disease severity caused by P. triticina without causing any injury to wheat leaves.  相似文献   
58.
Drug-induced liver toxicity is a common cause of liver injury. This study was designed to elucidate whether high dose vancomycin (VCM) induces oxidative stress in liver and to investigate the protective effects of erdosteine, an expectorant agent. Twenty-two young Wistar rats were divided into three groups as follows: control group, VCM, and VCM plus erdosteine. VCM was administered intraperitoneally in the dosage of 200 mg/kg twice daily for 7 days. Erdosteine was administered orally administered once a day at a dose of 10 mg/kg body weight. The activities of antioxidant enzymes such as superoxide dismutase and catalase as well as the concentration of malondialdehyde, as an indicator of lipid peroxidation, were measured to evaluate oxidative stress in homogenates of the liver. VCM administration increased malondialdehyde levels (p < 0.001), superoxide dismutase (p < 0.01) and catalase (p < 0.001) activities. Erdosteine co-administration with VCM injections caused significantly decreased malondialdehyde levels (p < 0.001), superoxide dismutase (p < 0.01) and catalase (p < 0.001) activities in liver tissue when compared with VCM alone. It can be concluded that erdosteine may prevent VCM-induced oxidative changes in liver by reducing reactive oxygen species.  相似文献   
59.
Sinan S  Kockar F  Arslan O 《Biochimie》2006,88(5):565-574
Human serum paraoxonase (PON1, EC 3.1.8.1.) is a high-density lipid (HDL)-associated, calcium-dependent enzyme; its physiological substrates are not known. In this study, a new purification strategy for human PON1 enzyme was developed using two-step procedures, namely ammonium sulfate precipitation and sepharose-4B-l-tyrosine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis of the enzyme indicates a single band with an apparent MW of 43 kDa. Overall purification rate of our method was found 227-fold. The V(max) and K(m) of the purified enzyme were determined 227.27 EU and 4.16 mM, respectively. The in vitro effects of commonly used antibiotics, namely gentamycin sulfate and cefazolin sodium was also investigated on the purified human serum PON1 enzyme and human liver PON1 enzyme from human hepatoma cell (HepG2). Gentamycin sulfate and cefazolin sodium caused a dose- and time-dependent decrease on PON1 activity in HepG2 cells. Moreover, gentamycin sulfate and cefazolin sodium were effective inhibitors on purified human serum PON1 activity with IC(50) of 0.887 and 0.0084 values, respectively. The kinetics of interaction of gentamycin sulfate and cefazolin sodium with the purified human serum PON1 indicated a different inhibition pattern. Cefazolin sodium showed a competitive inhibition with K(i) of 0.012+/-0.00065 mM. However, Gentamycin sulfate was inhibited in non-competitive manner with K(i) of 0.026+/-0.015. In order to determine the inhibition statue of these drugs on a living system, the effects of same antibiotics on PON1 enzyme activity of mouse serum PON1 and liver PON1 were investigated in vivo. Gentamycin sulfate (3.2 mg/kg) and cefazolin sodium (106.25 mg/kg) leads to the significant decrease in mouse serum PON1 after 2, 4, 6 h and 2, 4 h drug administration, respectively. Cefazolin sodium did not exhibit any inhibition effect for the liver PON1, in vivo.  相似文献   
60.
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