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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Gastric cancer still represents the second most common cause of gastrointestinal cancers in Germany. A disturbing issue is that at the time of diagnosis there are less than 15% of patients for whom a cure can be achieved. Nowadays, biological, histomorphological, molecular genetic and epidemiological data suggest that Helicobacter pylori eradication may lead to the prevention of gastric pre-neoplastic lesions and even gastric cancer. At present, eradication can be offered to selected patients and populations at increased risk, but more research is required before embarking on general and global H. pylori eradication for gastric cancer prevention. The main challenge is to determine how long mucosal abnormalities remain reversible and gastric cancer development can be halted. 相似文献
993.
994.
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
995.
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
996.
997.
V Pesakova P Gillery F X Maquart J P Borel M Adam 《Biomedicine & Pharmacotherapy》1991,45(10):455-459
The effects of some antirheumatics on the formation and retraction of collagen lattices seeded with fibroblasts have been studied. Among the antirheumatics, diclofenac was the most active inhibitor of lattice retraction, then tropesin and to a lesser extent indomethacin. Ibuprofen which is known as a very slight inhibitor of protein synthesis was able to significantly enhance lattice retraction when 10 micrograms/ml (48.5 microM) and 50 micrograms/ml (242 microM) were used. 相似文献
998.
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
999.
P E Anderson 《Dental economics》1986,76(3):73-4, 76, 79-80
1000.
From 1970 to 1980, 153 patients with stages A2, B1 and B2 prostatic cancer and proved negative pelvic lymph nodes underwent radical prostatectomy (84 underwent radical perineal and 69 underwent radical retropubic prostatectomy). Seventeen patients were lost to followup. Of 136 patients who were followed for 5 years or until death 128 (94 per cent) were alive at 5 years, including 118 (87 per cent) who were without evidence of recurrence. Patients with microscopic invasion of the prostatic capsule have a better outcome at 5 years than those with microscopic involvement of the seminal vesicles. Only 46 of the patients could be assessed at 10 years or had died 6 to 10 years postoperatively. Results at 10 years are considered preliminary, since many more patients will reach the 10-year milestone within the next few years. 相似文献