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71.
Purpose This work was carried out to follow up the healing of full-thickness incision wounds opened on the back skin of rabbits in order to gain insight into the periodical correlation among such factors as ascorbic acid, collagen (hydroxyproline), the zinc content, and tensile strength of wound tissue. The need to provide vitamin C or zinc supplements after such wound incisions is also discussed.Methods Full-thickness incision wounds and the ascorbic acid and hydroxyproline levels were measured in 24 rabbits by spectrophotometric methods on day 0 and on the 3rd, 5th, 7th, and 15th days after operation. The tensile strength was measured by a polygraph using a force displacement transducer. The zinc levels of the wounds were measured by atomic absorption spectrophotometry.Results The zinc and hydroxyproline levels reached the peak levels on the 5th day, but the tensile strength of wound increased sharply on the 7th day after wounding while the zinc levels did not change. These results indicated that in the first 7 days of wound healing, high levels of ascorbic acid, hydroxyproline, and zinc cumulation occurred in the wound tissue, and the tensile strength reached its highest level on the 15th day without any supplementation.Conclusion The supplementation of zinc and/or ascorbic acid should therefore be given just at the beginning of the wounding period, especially if there is deficiency of these nutrients. 相似文献
72.
Görenek G Akyilmaz E Dinçkaya E 《Artificial cells, blood substitutes, and immobilization biotechnology》2004,32(3):453-461
In this study, catalase enzyme was immobilized by entrapping in alginate beads in the presence of gelatin. In the optimization studies of the bioactive layer immobilized some parameters such as enzyme amount, alginate, gelatin, and crosslinking agent glutaraldehyde amount were determined as 700 U/mL, 2.0%, 18 mg/mL, and 5.0%, respectively. Effects of pH and temperature on the immobilization were also investigated. In the characterization studies of the immobilized enzyme storage and thermal stability experiments were done. The immobilized enzyme was used for the decomposition of hydrogen peroxide in milk samples and also by using a catalase biosensor prepared by the decomposition level of hydrogen peroxide was detected. 相似文献
73.
Walash M Sharaf-El Din M Metwalli ME RedaShabana M 《Archives of pharmacal research》2004,27(7):720-726
Two Spectrophotometric procedures are presented for the determination of two commonly used H2-receptor antagonists, nizatidine (I) and ranitidine hydrochloride (II). The methods are based mainly on charge transfer complexation reaction of these drugs with either p-chloranilic acid (rho-CA) or 2, 3 dichloro-5, 6-dicyanoquinone (DDQ). The produced colored products are quantified spectrophotometrically at 515 and 467 nm in chloranilic acid and DDQ methods, respectively. The molar ratios for the reaction products and the optimum assay conditions were studied. The methods determine the cited drugs in concentration ranges of 20-200 and 20-160 microg/mL for nizatidine and ranges of 20-240 and 20-140 microg/mL for ranitidine with chloranilic acid and DDQ methods, respectively. A more detailed investigation of the complexes formed was made with respect to their composition, association constant, molar absorptivity and free energy change. The proposed procedures were successfully utilized in the determination of the drugs in pharmaceutical preparations. The standard addition method was applied by adding nizatidine and ranitidine to the previously analyzed tablets or capsules. The recovery of each drug was calculated by comparing the concentration obtained from the spiked mixtures with those of the pure drug. The results of analysis of commercial tablets and the recovery study (standard addition method) of the cited drugs suggested that there is no interference from any excipients, which are present in tablets or capsules. Statistical comparison of the results was performed with regard to accuracy and precision using student's t-test and F-ratio at 95% confidence level. There is no significant difference between the reported and proposed methods with regard to accuracy and precision. 相似文献
74.
In vitro activity of beta-lactam antibiotics and their beta-lactamase inhibitor combinations were evaluated for their activity against clinical isolates of Mycobacterium tuberculosis and M. tuberculosis H37Ra. Agar dilution, the BACTEC 460 system and beta-lactamase activity tests were used. Results using the BACTEC 460 and enzyme activity tests showed the best beta-lactamase inhibitor for M. tuberculosis H37Ra to be clavulanic acid. Cefazolin-clavulanic acid gave the lowest minimal inhibitory concentration (MIC) values using dilution tests and M. tuberculosis H37Ra. beta-Lactam antibiotics were combined with clavulanic acid and tested for in vitro activity against 50 selected multidrug-resistant (MDR) and 50 susceptible clinical isolates. Seventy-four percent of the isolates were inhibited by cefazolin-clavulanic acid combination. These results suggested that an appropriate combination of beta-lactam and beta-lactamase inhibitors might be useful in the treatment of tuberculosis due to multidrug-resistant strains. 相似文献
75.
In this paper we developed a graphical method based on Haar (HA) and Mexican (MEX) one-dimensional continuous wavelet transforms and we applied it to a mixture of hydrochlorothiazide (HCT) and spironolactone (SP) in the presence of strongly overlapping signals. Keeping in mind to obtain an appropriately transformed spectrum, we tested several values of the scaling parameter a and the point number of the analysed spectrum in the concentration range of 2-22 microg/ml for both active compounds. The optimal values of the scale parameters and the corresponding frequencies were found to be a = 32 and 0.031 for HA and a = 30 and 0.008 for MEX corresponding to 400 points. HA and MEX methods based on a zero crossing technique were applied to the analysed signal and their regression lines at the selected points were obtained. The validation of the above methods was carried out by analysing different synthetic mixtures containing HCT and SP. MATLAB 6.5 software was used for one-dimensional wavelet analysis and the basic concepts about wavelet method were briefly explained. The method developed in this paper is rapid, easy to apply, inexpensive and is suitable for analysing the overlapping signals of compounds in their mixtures without any chemical pre-treatment. 相似文献
76.
77.
The Klippel-Trenaunay-Weber syndrome is a rare disorder characterized by congenital vascular hamartomas, limb hypertrophy, cutaneous manifestations, lymphangiomas and atresia of lymph vessels with non-pitting edema. A three-year-old boy was referred to our clinic for progressive hypertrophy of leg and feet with 32-month history. We diagnosed Klippel-Trenaunay-Weber syndrome, and determined vesicoureteral reflux in our patient. To our knowledge, hydronephrosis and vesicoureteral reflux have not been described previously in the KTWS. 相似文献
78.
79.
Abd Elhafez OM El Khrisy Eel D Badria F Fathy Ael D 《Archives of pharmacal research》2003,26(9):686-696
Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy)methyl]-4-acetyl-5-substituted-delta2-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied. 相似文献
80.
Evaluation of O6-methylguanine DNA methyltransferase activity in patients with gastric cancer 总被引:1,自引:0,他引:1
O6-Methylguanine DNA methyltransferase (O6-MGMT) reverses DNA alkylation damage produced alkylating agents. O6-MGMT is also a major determinant of cellular resistance to adjuvant chemotherapy with alkylating drugs. O6-MGMT activity was measured in samples from patients with gastric cancer, including tumor, adjacent normal appearing mucosa, and peripheral blood leukocytes (PBL). O6-MGMT activity of PBL from healthy individuals was evaluated as control. There was no significant difference between controls and patients for O6-MGMT activity in PBL. O6-MGMT activity was significantly increased in tumor tissue. Tumor O6-MGMT activity was found to be independent from tumor subgroups and tumor grade. A positive correlation was determined between O6-MGMT activity in tumor and in circulating PBL. The results indicate that O6-MGMT, a defense protein against alkylating agent-mediated carcinogenesis, increased in gastric tumors. This may explain the low response rate to drug combinations, including chloroethylnitrosoureas, exhibited by patients with gastric cancer. 相似文献