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International Journal of Peptide Research and Therapeutics - Influenza A viruses are among the most studied viruses, however no effective prevention against influenza infection has been developed....  相似文献   
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Ozturk Urek  Raziye  Ilgin  Seda 《Annals of microbiology》2019,69(11):1201-1210
Microbial exopolysaccharides (EPSs) are very important because they are used in biotechnological applications in different industrial areas. The aim of the study was to determine the best EPS producer Pleurotus sp., to optimize EPS production and to perform partial purification and characterization of the produced EPS. After the production conditions were optimized, the EPS was isolated and partially purified. EPS was characterized by HP-TLC, 1H-NMR, FT-IR, and TGA. Hydroxyl, superoxide, and DPPH radical scavenging activities of the EPS were also investigated spectrophotometrically. The best EPS producer and its incubation period in submerged fermentation were determined as Pleurotus sajor caju and on 5 days, respectively. Culture conditions to increase EPS production were optimized as follows (in per liter): 90 g of glucose, 10 g of yeast extract, 10 g of peptone, and 100 mM of Mg2+. The optimal initial pH, temperature, and an agitation rate of culture were determined as 5.0, 25 °C, and 150 rate min−1, respectively. The highest EPS production was determined as 33.32 ± 1.6 g L−1. After isolation of EPS, one active fraction was obtained by gel filtration chromatography. EPS is composed mainly of glucose according to HP-TLC analysis. To the results, EPS had a complex structure by having carbohydrate and protein contents. The produced EPS had high degradation temperature as well as high antioxidant activity.  相似文献   
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We aimed to assess the association between IGF-I gene (CA repeats) polymorphism in breast cancer patients and their clinicopathological features, as well as disease recurrence and survival. Seventy-six non-metastatic breast cancer patients were enrolled in the present study. The IGF-I (CA) repeats were studied with polymerase chain reaction by using proper primers belonging to these gene areas from DNA samples. Results show that the non 19- non 19 homozygote were more common in patients without lymph node involvement (p=0.04), with low histological grade (p=0.04), with positive hormone receptor status (p=0.01), and in patients without recurrence (p=0.06). These results suggest that the non 19-non 19 carriers have some favorable prognostic factors, and IGF-I gene polymorphism (CA repeats) may affect disease recurrence and overall survival.  相似文献   
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P-glycoprotein (Pgp) is encoded by the multidrug resistance gene (MDR1) in humans and is the product of MDR1. It is expressed in various tissues and is related to drug distribution in intestinal erythrocytes, capillary endotel of brain, proximal tubules cells of kidneys and liver canalicular cells. Expression of Pgp is affected by Pgp polymorphism, and exon 26 C3435T polymorphism is the most common one. It has been thought that expression of Pgp is high in C-allele subjects and this situation is responsible for the resistance against some drugs and substances. Pgp may have a role in the distribution of thyroid hormones, drugs used for hypo- and hyperthyroidism and the resistance occurred. For this purpose possible relationship between T and C alleles and frequency of Pgp polymorphism as well as thyroid hormone distribution in patients with hypo- and hyperthyroidism was investigated. Thirty five hyperthyroidism patients diagnosed as Graves’ disease, 78 hypothyroidism patients diagnosed as Hashimoto’s thyroiditis and 100 healthy volunteers were included in the study. According to the results obtained no statistically significant difference was found in Pgp C3435T polymorphism between hypo- and hyperthyroidism patients. In addition, the serum free T3 levels of hyperthyroidism patients with C alleles was higher than those of subjects with T alleles. No statistically significant difference was seen in the CC, CT and TT genotype frequencies between the patients and control groups. In conclusion, it seems that Pgp polymorphism is not a predictor factor for the occurrence of hypo- and hyperthyroidism. There is a significant relationship between Pgp and the elevated serum free T3 levels of hyperthyroidism patients, and further research will help understand this situation.  相似文献   
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Acromegaly is associated with increased morbidity and mortality related to cardiovascular disease. Hypertension is one of the most common cardiovascular risk factors in acromegalic patients. The aim of this study was to investigate association between the frequencies of angiotensin converting enzyme (ACE) I/D, angiotensinogen (AGT) M235T and the angiotensin II type 1 receptor (AT1-R) A/C1166 gene polymorphisms and some clinical parameters of acromegalic patients. Total of 33 acromegalic patients and 63 controls were enrolled to study. We determined the ACE I/D, AGT M235T and AT1-R A/C1166 gene polymorphisms. Serum insulin, glucose, triglyceride, HDL-cholesterol, LDL-cholesterol, growth hormone and Insulin-like growth factor I (IGF-I) levels of subjects were analyzed. The frequencies of ACE and M235T AGT genotype were not significantly different between control and patients. The distribution of AT1R A/C1166 genotypes was significantly different between patients and control subjects (P = 0.016). None of the three ACE genotypes, DD, ID and II displayed significant difference in acromegalic patients. A significant difference in systolic blood pressure and the serum IGF-I levels among the three AGT genotype, MM, MT and TT genotypes was found in patient group. Individuals with MT genotypes had significantly higher serum IGF-I levels and systolic blood pressure than MM and TT genotype subjects, P < 0.05. In addition, serum triglyceride and HDL levels differed significantly between MM and MT genotypes, P < 0.05. However, systolic blood pressure of patients with CC genotypes was found to be significantly higher than AA genotypes individuals in acromegaly group, P < 0.05. It can be said that the angiotensinojen MT and AT1R CC1166 genotype carriers may have more risk than other genotypes in the development of hypertension in acromegaly.  相似文献   
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Biosurfactants are amphiphilic compounds produced by several microorganisms that reduce the surface tension. Low toxicity, optimal activity in extreme conditions, biodegradability and production from several wastes are main advantages of biosurfactants as compared to synthetic surfactants. Production of biosurfactant by a white rot fungus Pleurotus djamor on sunflower seed shell in solid-state fermentation was determined by emulsification indexes, oil spreading activity and surface tension (28.82 ± 0.3mN/m) measurement. The critical micelle concentration was detected as 0.964 ± 0.09 mg/mL. Also, the chemical and physicochemical properties of the biosurfactant produced were investigated. Considering the results of the chemical contents analysis, HPLC, FT-IR and 1H-NMR, it can be concluded that the produced biosurfactant has a complex structure. Besides, resistance of its activity to environmental factors such as temperature, pH and salt concentration, as well as its thermal stability, were investigated. Additionally, the produced biosurfactant formed stabile emulsions with different hydrocarbons. Lastly, the performance of removing waste frying oil from contaminated sand of produced biosurfactant was detected as 76.57 ± 6%. Owing to its high emulsification capacity, low surface tension and critical micelle concentration, the biosurfactant, shows great potential for use in hydrocarbon removal applications.  相似文献   
7.
Journal of Plant Research - This research hypothesized that tolerance of cucumber seedlings to salinity stress could be increased by hydrogen sulfide (H2S) treatments. In pot experiments, the...  相似文献   
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Solid-state culture of the white-rot fungus Phanerochaete chrysosporium BKMF-1767 (ATCC 24725) has been carried out, using an inert support, polystyrene foam. Suitable medium and culture conditions have been chosen to favor the secretion of manganese peroxidase (MnP). The enzyme was isolated and purified from immobilized P. chrysosporium and partially characterized. Partial protein precipitation in crude enzyme was affected using ammonium sulphate, polyethylene glycol, methanol, and ethanol methods. Fractionation of MnP was performed by DEAE-Sepharose ion exchange chromatography followed by Ultragel AcA 54 gel filtration chromatography. This purification attained 23.08% activity yield with a purification factor of 5.8. According to data on gel filtration chromatography and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), the molecular weight of the enzyme was 45 000±1000 Da. The optimum pH and temperature of purified MnP were 4.5 and 30 °C, respectively. This enzyme was stable in the pH range 4.5–6.0, at 25 °C and also up to 35 °C at pH 4.5 for 1 h incubation period. MnP activity was inhibited by 2 mM NaN3, ascorbic acid, β-mercaptoethanol and dithreitol. The Km values of MnP for hydrogen peroxide and 2.6-dimetoxyphenol were 71.4 and 28.57 μM at pH 4.5, respectively. The effects of possible inhibitors and activators of enzyme activity were investigated.  相似文献   
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