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991.
G. B. Slepchenko L. S. Anisimova V. F. Slipchenko E. V. Mikheeva N. P. Pikula 《Pharmaceutical Chemistry Journal》2005,39(3):166-168
Rapid voltammetric procedures for the determination of water-soluble vitamins C, B1, and B2, fat-soluble vitamin E (α-tocopherol acetate), and quercetin in bioactive food additives have been developed. The systematic error (i.e., correctness) of the proposed procedures was evaluated using certified reference materials and the additive recovery tests, which gave the following limiting metrological characteristics: relative error, 25 %; reproducibility, 28 %; convergence, 22 %. The full analysis time (with sample preparation) did not exceed 2 hours. Voltammetric determinations under optimum conditions can be performed in the automated regime controlled by a computer according to the specially developed software.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 3, pp. 54 – 56, March, 2005. 相似文献
992.
L. A. Trukhacheva V. I. Levina A. P. Arzamastsev N. B. Grigor'ev V. G. Granik 《Pharmaceutical Chemistry Journal》2005,39(6):296-299
The kinetics of alkaline hydrolysis of N-(5-nitro-2-thiazolyl)-2-thiophenylcarboxamide (tenonitrozole or atrican) has been studied by photometric and polarographic
techniques, and the thermodynamic parameters in the intermediate state of this process were determined. A mechanism explaining
the nitric oxide (NO) production during the hydrolytic decomposition of tenonitrozole is proposed. It is suggested that the
antiprotozoal and antimicrobial activity of this drug under anaerobic conditions is related to the formation of nitro radical
anions and NO. Under aerobic and microaerophilic conditions, the hydrolysis of tenonitrozole may lead to the formation of
a peroxynitrite anion, which is a strong cytotoxic agent.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 6, pp. 15 – 18, June, 2005. 相似文献
993.
The antibiotics that are recommended for treatment of pelvic inflammatory disease (PID) in the outpatient setting are efficacious against Neisseria gonorrhoeae and Chlamydia trachomatis. The susceptibility of non-sexually transmitted pathogens to these agents has not been well studied. The mean inhibitory concentrations of ampicillin, cefpodoxime, metronidazole, and doxycycline were determined for 137 upper-genital tract isolates from 84 women with confirmed PID. Antibiotic resistance was noted in 16%, 9%, 93%, and 72% of the facultative and 0%, 11%, 10%, and 56% of the anaerobic bacteria when tested against ampicillin, cefpodoxime, metronidazole, and doxycycline, respectively. The authors conclude that doxycycline is limited to coverage of Chlamydia and that a single dose of another antibiotic may not be adequate to eradicate the non-sexually transmitted disease pathogens from the upper-genital tract. Additional clinical and microbiologic studies are needed to determine whether the current outpatient antibiotic regimens provide optimal coverage for the non-sexually transmitted pathogens that are associated with PID. 相似文献
994.
The effect of chronic inflammation on gingival connective tissue proteoglycans and hyaluronic acid 总被引:1,自引:0,他引:1
Proteoglycans have been isolated and analysed from extracts of normal and chronically inflamed human gingiva in order to determine the effects of chronic inflammation on these important soft connective tissue extracellular macromolecules. The uronic acid content of glycosaminoglycans isolated by papain digestion of normal and inflamed gingiva did not differ significantly. Likewise, electrophoretic analysis revealed that the content of hyaluronic acid, heparan sulfate, dermatan sulfate and chondroitin sulfute was similar. The sulfated glycosaminoglycans from both sources eluted from a Sepharose C1-6B column with a Kav of 0.45 (approximate Mr 25,000). However, hyaluronic acid from normal gingiva was predominantly of a large size eluting in the void volume of a Sepharose. CL-6B column, while that isolated from inflamed tissue was mostly a small molecular weight species which elutccl in the included volume of a Sepharose CL-6B column. Using dissociative conditions, intact proteoglycans could be more readily extracted from inflamed tissues (90% of the total tissue uronic acid) than from normal tissues where only 80% of the total tissue uronic acid was extractable. Even though DEAE-Sephacel ion-exchange chromatography revealed no differences in charge between normal and inflamed gingival proteoglycans, Sepharose CL-4B chromatography revealed more molecular size polydispersity in samples from inflamed tissue than from normal tissue. Taken together, these results indicate that while hyaluronic acid is depolymerized in inflamed tissue, no evidence of sulfated glycosaminoglycan degradation was found. Therefore, the most likely cause for disruption to the molecular integrity of the proteoglycans is via proteolytic alteration to the proteoglycan core protein. 相似文献
995.
996.
The Monk Duopleet femoral interlocking uncemented two-component endoprosthesis consists of a polyethylene cup covered by a metal cap and an Austin-Moore type stem. Seventy-two patients (average age, 71 years) were treated by this arthroplasty: 27 for subcapital femoral neck fracture, 36 for osteoarthritis, and nine as an exchange operation. Three patients died following operation. After a mean follow-up time of 50 months, 47 patients were reexamined clinically and radiographically. Because of loosening, four patients had the prosthesis removed. Twenty-six patients were classified as excellent, 12 as good, six as fair, and three as poor. There were no cases of acetabular intrusion. The Monk Duopleet prosthesis may solve the problem of the loosening that had been associated with femoral component alone. The long-term results are promising and appear to be better than the results of the standard Moore prosthesis. The Monk Duopleet prosthesis is an alternative to other two-component endoprostheses for the treatment of subcapital hip fractures and in the group of patients suffering from osteoarthritis, where an arthroplasty with a cemented prosthesis may be considered hazardous because of age or general disease. 相似文献
997.
998.
M Herbst H Fritz H G Nüsslein B J Manger J R Kalden R Sauer 《Strahlentherapie und Onkologie》1986,162(1):25-30
Eleven patients with refractory rheumatoid arthritis were submitted to a total lymphoid irradiation up to a dose of 20 Gy. A constant improvement of clinical symptoms was observed in four out of the eleven patients already during the treatment and in the other patients not later than two months after. The frequency of attacks decreased and the number of joints involved in the attack was reduced. Morning rigidity and joint swellings decreased. One patient developed joint empyemas 4 and 26 months after the treatment. Four patients died in the meantime. In two patients the cause of death were renal insufficiency and a postoperative cardiogenic shock associated with generalized amyloidosis. The third patient died because of a toxically induced left cardiac decompensation with sepsis that could not be controlled by antibiotic drugs and multiple joint empyemas. The fourth patient developed an abscess after surgical treatment of a Kaposi syndrome. She died three months later from acute left cardiac decompensation. The therapy induced a lymphocytopenia with decrease of T helper lymphocytes and unchanged number of T suppressor lymphocytes. The constant therapy results of total lymphoid irradiation in primary chronic polyarthritis is probably due to this modification in the immune regulation. 相似文献
999.
E D Endean S K Mukhopadhyay L K Fung J L Cronenwett J C Stanley S M Lindenauer 《The Journal of surgical research》1986,40(1):49-54
Basal isolated canine paw blood flow was equally distributed between arteriovenous anastomosis (AVA) and capillary circulations. Norepinephrine decreased AVA flow by 92% and capillary flow by 41%. Dopamine significantly reduced AVA flow by 94% compared to baseline with a 37% reduction in capillary flow. However, with alpha-adrenergic blockade dopamine decreased AVA flow 66% while capillary flow increased 42%. Isoproterenol increased capillary flow almost twofold and appeared to decrease AVA flow, although the latter was statistically insignificant. Differential effects of adrenergic and dopaminergic agonists on canine paw AVA and capillary blood flow suggest the existence of independent regulation of these components of the microcirculation. 相似文献
1000.
Mitogen responsiveness of lymphocytes from the BB/W rat 总被引:3,自引:0,他引:3
The response of BB diabetes-prone (DP) and W-line non-diabetes-prone rats to the T-cell mitogen concanavalin A (ConA) was measured. The W line was a good responder to ConA, whereas the DP was relatively unresponsive. This unresponsiveness could not be reversed with exogenous interleukin 2 (IL-2). The response of DP rats was enhanced by removing adherent cells. To directly test the response of BB T-cells, they were isolated by flow sorting. These experiments demonstrated that BB T-cells could mount a normal ConA response. The normal function of isolated BB T-cells suggested that they were under suppression. Suppressor activity could not be found in the OX8+ population but was found in the DP-adherent cell population. Adherent cells from the W line were not suppressive at the concentrations used. These results showed that the decreased mitogen responsiveness of BB T-cells was not due to an intrinsic T-cell abnormality but was due, in part, to suppression by adherent cells. 相似文献