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131.
Recombinant tissue plasminogen activator (rt-PA) is one of the most important thrombolytic agents for treating cardiovascular obstructions such as stroke. Glycoprotein rt-PA is a serine protease, consisting of 527 amino acids of which 35 are cysteine residues. A variety of recombinant protein expression systems have been developed for heterologous gene expression in prokaryotic and eukaryotic hosts. In recent years, Leishmania tarentolae has been considered because of its safety aspects and special attributes in expression of complex proteins. In this study, two expression cassettes, each one including two copies of t-PA cDNA, were used for integration into the L. tarentolae genome by electroporation. Transformed clones were selected in the presence of appropriate antibiotics. Expression of active rt-PA was confirmed by Western blot and Zymography tests. Real-time PCR analysis was applied to investigate the presence of multiple t-PA gene copies in the parasite genome. Correlation of t-PA gene dosage and production rate was confirmed with real-time PCR. It was shown that the expression level of rt-PA in L. tarentolae is at least 480 IU/mL of culture media. This concentration of rt-PA is seven times higher than what was reported in previous studies in L. tarentolae and some other eukaryotic systems.  相似文献   
132.
Molecular Biology Reports - Clinical application of doxorubicin (DOX) is restricted due to its cardiotoxicity, reinforcing the significance of exploring new strategies to counteract DOX-induced...  相似文献   
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Background  

The effects of ovarian drilling on the serum levels of gonadotropins and androgens have been studied previously. The aim of this study is to evaluate the effects of ovarian drilling on the serum prolactin levels and its relation to ovulation in women with polycystic ovary syndrome.  相似文献   
135.
A new series of 1-N-thiocarboxamide-3-phenyl-2-pyrazolines 1-6 was synthesized by cyclization of different Mannich bases with unsubstituted thiosemicarbazide. The reaction of cyclized pyrazoline derivatives 1-6 with 2,3-dichloroquinoxaline afforded the title compounds 7-12. The structures of the new compounds were confirmed by elemental analyses as well as (1)H, (13)C NMR, IR and electronic spectral data. The HM1:IMSS strain of Entamoeba histolytica parasite was cultured in vitro and the sensitivity of the parasite to the synthesized compounds was evaluated using the microdilution method. Among all the pyrazoline derivatives 1-6, none was found to be a better inhibitor as compared to the reference drug, metronidazole. The quinoxaline derivatives, 9, 11 and 12 were found to be potent inhibitors of E. histolytica.  相似文献   
136.
Ethambutol is an oral anti-tuberculosis agent with chelating effects owing to its chemical structure which is similar to that of penicillamine. Copper (Cu) is an essential trace element that has important roles in physiological function of the body organs. The aim of present study was to determine (1) whether ethambutol usage can alter serum Cu concentration in patients with tuberculosis and (2) whether there is any relationship between age, sex, and smoking habit of patients with changes in serum Cu levels. Sixty patients with diagnosis of pulmonary tuberculosis were enrolled the study. Blood samples were obtained before treatment (baseline) and 10 days after starting anti-tuberculosis therapy. The amounts of serum Cu were determined in all samples by atomic absorption. Mean ± SD levels of Cu at baseline and on the 10th day of ethambutol use were 0.94 ± 0.24 and 0.64 ± 0.24 μg/mL, respectively. Statistical analysis confirmed a significant difference (p < 0.0001). Also, there was not any relationship between changes in Cu concentration and study variables of age, sex, and smoking habit. Our findings endorse the chelating effect of ethambutol leading to a decrease in serum levels of cationic trace elements, e.g., Cu.  相似文献   
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Background aimsThe aim was to investigate the therapeutic effect of granulocyte–colony-stimulating factor (G-CSF) administration following implantation of autologous bone marrow mononuclear cells (BM MNC) for patients with lower limb ischemia.MethodsThe design was a randomized controlled trial. Fifteen patients with severe chronic limb ischemia were treated with autologous BM MNC [without G-CSF (MNC–G-CSF) or combined with G-CSF administration for 5 days following transplantation (MNC+G-CSF)].ResultsAll clinical parameters, including ankle brachial index, visual analog scale and pain-free walking distance, showed a mean improvement from baseline, which was measured at 4 and 24 weeks after transplantation in both groups. However, in three (20%) patients, the clinical course did not improve and limb salvage was not achieved. No significant difference was observed among the patients treated in the MNC–G-CSF and MNC+G-CSF groups. No severe adverse reactions were reported during the study period. No relationship was observed between both the numbers of viable MNC or CD34+ cells and the clinical outcome.ConclusionsAutologous transplantation of BM MNC into ischemic lower limbs is safe, feasible and efficient for patients with severe peripheral artery disease. However, the administration of G-CSF following cell transplantation does not improve the effect of BM MNC implantation and therefore would not have any beneficial value in clinical applications of such cases.  相似文献   
139.
The present study was designed to evaluate the effects of parenteral iron on red blood cell parameters, performance, and health in dairy Holstein calves. Twenty neonatal calves were equally divided at random into two groups, one of which served as controls. Care was taken to ensure homogeneity of sex, age, and general health status of the animals. The controls received a normal diet and water ad libitum, while the study animals were injected with 1 g iron as Fe-dextran 2 days after birth. A daily record was kept of the calves’ weight and growth parameters. At periods of 24–48 h after birth and at 14, 28, and 42 days of age, jugular blood was drawn from all the experimental and control animals to measure the packed cell volume, red blood count, hemoglobin, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and iron levels. At the start of the experiments, there were no significant differences between these parameters between the two study groups (p > 0.05). With time, significant differences were seen between most of the values measured (p < 0.05) except for the mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and iron level. Significant differences were seen for total weight gain and mean daily weight gain, which were higher in the iron-supplemented group (p < 0.05).  相似文献   
140.
Investigations were made on rearing, reproductive behaviour and gamma sterilization of one-day old male adults of Dacus zonatus. The larvae were successfully reared on an artificial diet based on wheat shorts. Adult emergence ranged from 89–99% with a sex ratio of about 1:1. Mating occurred at dusk and its duration ranged from 8–13 hours. Males mated a second time with the same female but preferred mating if the already mated female was replaced with a sexually mature virgin female. The optimum dosage for inducing sterility amongst one-day old male adults was 12 kR.
Zusammenfassung Zucht und Fortpflanzungsverhalten von Dacus zonatus (Saunders) wurde untersucht. Die Larven wurden vier Generationen lang an einer Diät aus Weizenkleie, Bierhefe, granuliertem Zucker, Agar, Nipagin, Salzsäure und Wasser gehalten. Die Arbeit gibt Daten über Verpuppungsprozentsatz (69,3%), Puppengewicht, Dauer der Ei + Larvenperiode, Schlüpfen der Adulten, Präovipositionszeit, Fruchtbarkeit, Fertilität und Lebensdauer der Adulten. Die Schlüpfrate der Adulten betrug 89–99%, das Geschlechtsverhältnis lag etwa bei 1:1. Die Kopulation findet während der Abenddämmerung statt, sie dauert 8–13 Stunden. Maximum der Kopulationen zwischen dem 10. und 15. Tag nach dem Schlüpfen. Männchen paarten sich ein zweites Mal mit dem gleichen Weibchen, bevorzugten jedoch geschlechtsreife jung-fräuliche Weibchen. Die Eiablage begann am 2.–7. Tag nach der Paarung, die Eizahl betrug bei gepaarten Weibchen 91–564.Die optimale Dosis zur Erzeugung von 99,3% Sterilität bei Bestrahlung von einem Tag alten Männchen war 12 kR. Die Lebensdauer der Bestrahlten war vermindert.
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