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排序方式: 共有2021条查询结果,搜索用时 15 毫秒
1.
Objective:To study the effect of oral administration of dimethyl dimethoxy biphenyl dicarboxylate(DDB) on adjusting angiogeneic/inflammatory mediators and ameliorating the pathology of bones in rats with collagen-induced arthritis(CIA).Methods:Wistar rat model of CIA was set up using bovine collagen type Ⅱ.Fifty rats were divided into five groups randomly:normal,CIA model,DDB treatment,methotrexate(MTX) treatment,and combined DDB+MTX treatment.Ankle joints of rats were imaged with digital X-ray machine to show the destruction of joints.Fore and hind paw and knee joints were removed above the ankle joint then processed for haematoxylin and eosin staining.Plasma levels of vascular endothelial growth factor(VEGF),platelet derived growth factor,interleukin-8(IL-8),IL-4,tumor necrosis factor α(TNF-α),and cyclooxygenase-2(COX-2) were quantified by enzyme-linked immunosorbent assay.Nitric oxide levels were detected by Griess reagent.Results:Compared with the CIA model group,a remarkable reduction in various angiogenic(VEGF and IL-8) and inflammatory mediators(TNF-α,IL-4 and COX-2) after treatment with DDB either alone or combined with MTX(P0.05 or P0.01).Histopathological and X-ray findings were confirmatory to the observed DDB anti-arthritic effect.The DDB-treated group showed amelioration in signs of arthritis which appeared essentially similar to normal.Conclusion:Our data shed light on the therapeutic efficacy of DDB in experimental rheumatoid arthritis(RA) compared with a choice drug(MTX) and it may be offered as a second-line drug in the treatment of RA. 相似文献
2.
The metabolic disposition of N-(1-methyl-3,3-diphenylpropyl) formamide was studied in rats. The water-soluble metabolites, N-acetyl-S-[N-(1-methyl-3,3-diphenylpropylcarbamoyl)]cysteine and S-[N-(1-methyl-3,3-diphenylpropylcarbamoyl)]glutathione, were identified in urine and bile, respectively, of rats doses with the secondary formamide. The structures of these metabolites were confirmed by comparison with synthetic standards and by using liquid chromatography mass spectrometry and fast atom bombardment mass spectrometry. Synthetic standards of these metabolites were obtained by reacting the N-(1-methyl-3,3-diphenylpropyl)isocyanate with glutathione or N-acetylcysteine in methanolic solutions. The isocyanate was obtained in high yield by reacting 1-methyl-3,3-diphenylpropylamine with trichloromethyl chloroformate. The S-linked conjugates released the isocyanate in mild alkali, but were stable under acidic conditions. The released isocyanate was characterized by comparison with the synthetic standard using GC/MS and HPLC. A mechanism is proposed for the base-catalyzed elimination of the isocyanate from the thiol conjugates. 相似文献
3.
The broad background of scattered light observed in spectra of cell suspensions is reduced by factors of up to 20 by immersion refractometry allowing for improved spectroscopic determination of the absorption properties of cells in the 325-820 nm range. Refractive-index matched spectra of E. coli C1a exhibit a set of resonant features near 422, 561, and 582 nm. Exposure wavelengths are chosen based on this spectrum and cell viability is investigated in E. coli suspensions exposed to 350, 400, 422, 440, and 700 nm radiation delivered in nanosecond pulses with total doses from 500 millijoules to 60 Joules. We observe a loss in cell viability for doses greater than 1 Joule at 422 nm and for all doses at other wavelengths; exposures of less than 1 Joule at 422 nm enhance growth. Excluding exposures at wavelengths within the resonant feature, longer wavelengths are less effective at reducing the viability of E. coli C1a. This indicates the occurrence of at least two absorption processes. 相似文献
4.
Concomitant administration of cyclosporine and ketoconazole in idiopathic nephrotic syndrome. 总被引:1,自引:1,他引:0
Amr El-Husseini Fathy El-Basuony Ahmed Donia Ihab Mahmoud Nabil Hassan Nagy Sayed-Ahmad Mohamed Sobh 《Nephrology, dialysis, transplantation》2004,19(9):2266-2271
BACKGROUND: The deliberate use of ketoconazole to reduce the need for cyclosporine (CsA) is not new, but it is particularly relevant because of the high cost of CsA. Many studies have documented this benefit in renal and cardiac transplants, but this co-administration has not been reported in patients with nephrotic syndrome. METHODS: This retrospective study included 207 nephrotic patients who were steroid resistant, dependent or frequent relapsers and received CsA therapy. Among these patients 153 received daily ketoconazole therapy in a dose of 50 mg with concomitant decrease of one-third of the CsA dose while 54 patients received CsA alone. The majority of our cases were children (179 were below 18 years) and male to female ratio was 1.7:1. RESULTS: The great majority of the study population received the drugs for 1-2 years. Patients who received CsA and ketoconazole were comparable with those who received CsA alone regarding age, sex, duration of renal disease, renal pathology, severity of nephrotic syndrome, renal function, hepatic function and steroid response. Co-administration of ketoconazole significantly reduced mean doses of CsA by 37% after 1 month and 47% at 1 year with overall net cost savings of 37%. Hepatic functions remained within the normal range in both groups. Additionally, co-administration of ketoconazole significantly improved the response to CsA therapy, successful steroid withdrawal and decreased the frequency of renal impairment. CONCLUSIONS: Co-administration of keto with CsA in idiopathic nephrotic patients significantly reduces CsA costs and may improve its response. 相似文献
5.
Ibraheim A. Naga Francois B. Sakla Zaiful A. Girgis Fathy A. State 《Developmental dynamics》1970,129(1):53-63
Twenty-five rabbits were used to study the effect of glossopharyngeal nerve transection upon the number, size and cellular constitution of the taste buds. The glossopharyngeal nerve was cut on one side, the other being left undisturbed as a control. The animals were sacrificed in groups of three after 7, 10, 14, 21, and 30 days, and 2 and 4 months after the operation. Seven days after the operation the size and number of intragemmal cells were decreased in the taste buds. The taste pores with hairlets passing through them disappeared. The number of taste buds on circumvallate papillae decreased. After ten days taste buds in both types of papillae showed signs of degeneration. Fourteen days after the operation there was a marked decrease in size and number of taste buds. The circumvallate papillae now possessed no taste buds. After 21 days few taste buds were present in foliate gutters. These consisted of one or two sustentacular cells each. After 30 days there were no taste buds on foliate papillae, and thickness of the epithelium lining the gutters was decreased. Two or four months after denervation, the foliate gutters were shallow and some had become flattened. The importance of the gustatory nerve for development and maintenance of the normal status of the taste buds is discussed. 相似文献
6.
The ability of several bacterial species to adhere to human nasal mucosal cells and their distribution on nasal mucosal surfaces was studied. Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, and Pseudomonas aeruginosa adhered to scraped nasal mucosal cells. In contrast, viridans streptococci and Klebsiella pneumoniae exhibited feeble or no adherence to nasal mucosal cells. S. aureus affinity for the nasal mucosal cells of carriers of S. aureus was greater than for those of the noncarriers (P less than 0.005). Heat treatment of S. aureus did not block, but slightly reduced, its binding to mucosal cells. The data suggest a high degree of specificity involved in the adherence of bacteria to nasal mucosal cells. The greater affinity of S. aureus for the nasal mucosal cells of carriers (than noncarriers) seems to be a property of mucosal cells rather than bacteria. 相似文献
7.
Protection of Chicken Embryos by Viridans Streptococci Against the Lethal Effect of Staphylococcus aureus 总被引:2,自引:0,他引:2 下载免费PDF全文
Raza Aly Howard I. Maibach Henry R. Shinefield Adrian D. Mandel 《Infection and immunity》1974,9(3):559-563
Chicken embryos were used to investigate the mechanism by which viridans streptococci inhibit the growth of pathogenic staphylococci. Ten-day-old embryonated eggs were infected allantoically. At a concentration of 1.8 x 10(2) colony-forming units (CFU) of viridans streptococci, the percentage of fatalities was less than 10%. There was 80% fatality with 8 x 10(1) CFU of Staphylococcus aureus strain 502A and 100% when a 100-fold increase in concentration was used. An inoculum size of 10(2) to 10(3) CFU of viridans streptococci was chosen to protect the embryos against the lethal effect of strain 502A when challenged 24 h later. The survival after challenging at 4 days was 93% in protected eggs and 37% in unprotected eggs. Chicken embryos receiving heat-killed viridans and challenged with strain 502A when examined after 4 days did not demonstrate a protective effect. This protection of embryonated eggs could not be transferred by administration of sterile filtrate of allantoic fluid in which protecting strain was grown. The experimental infection of embryonated eggs has demonstrated that prior allantoic infection with viridans streptococci affords significant protection against subsequent challenge with virulent staphylococci. 相似文献
8.
Magdy S. Aly Paola Dal Cin Herman Van Den Berghe Wim Van De Voorde Hein Van Poppel Filip Ameye Luc Baert 《Genes, chromosomes & cancer》1994,9(4):227-233
We combined conventional cytogenetic analysis and fluorescence in situ hybridization of short-term cultures of 28 samples from benign prostatic hyperplasia. Lou of the Y chromosome was the most common chromosome change, followed by trisomy 7. Trisomy 7, however, may be unrelated to the origin of benign prostate hyperplasia, in which the only and not very specific change seems to be the loss of the Y chromosome. Genes Chrom Cancer 9:227-233 (1594). © 1994 Wiley-Liss, Inc. 相似文献
9.
Paola Dal Cin Chris De Wolf-Peeters Magdy S. Aly Georges Deneffe Walter Van Mieghem Herman Van Den Berghe 《Genes, chromosomes & cancer》1993,6(4):243-244
Cytogenetic analysis of a thymoma showed the presence of a ring chromosome 6 as the sole chromosome abnormality. © 1993 Wiley-Liss, Inc. 相似文献
10.
Mahmoud Hassanein El-Saied A. Aly Yousf A. Abbas Samia M. El-Sigeny 《Macromolecular chemistry and physics.》1993,194(6):1817-1825
To overcome mass transfer limitations which are usually encountered on immobilizing active catalysts, cationic latex particles were used as support for the cobalt(II) complex of disodium N,N′-bis(salicylidene)ethylenediamine-5,5′-disulfonate ( 1 ). The cationic latex 2 was prepared by emulsion copolymerization of chloromethylstyrene (m/p-isomer mixture 60/40) and divinylbenzene (m/p-isomer mixture) followed by treatment with trimethylamine. The latexbound catalyst from 1 and 2 was found to considerably increase the reaction rate of the autoxidation of 2,6-di-tert-butylphenol in water as compared with the conventional polymer-free system. Reaction products were identified as the oxidative coupling product 3,3′,5,5′-tetra-tert-butyldiphenoquinone (3,3′,5,5′-tetra-tert-butyl-4,4′-dioxo-1,1′-bicyclohexa-2,5-dienylidene) and 2,6-di-tert-butyl-1,4-benzoquinone. All reactions showed an induction period before the start of dioxygen consumption. The rate of autoxidation in the three-phase mixtures of water, latex particles, and phenol droplets was not affected significantly by the method of mixing. The reaction rate increased as the concentration of 1 increased. Increasing the partial pressure of dioxygen in the range between 0,25 and 1,0 atm (2,53. 104 – 1,01. 105 Pa) gave a small increase in rate. The colloidal latex catalyst from 1 and 2 showed some loss of activity after successive runs. 相似文献