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991.
PURPOSE: We have investigated T Lymphocytes ability for CD69 molecule induction in presence and absence of monocytes in idiopathic uveitis. MATERIAL AND METHODS: Twenty-five children with idiopathic uveitis were studied. The control group consisted of 12 healthy children. Peripheral blood mononuclear cells (PBMCs) were isolated from heparinised venous blood, by density gradient centrifugation. CD69 expression was cytometrically assessed on freshly isolated and cultured T lymphocytes. RESULTS: CD69 expression on freshly isolated peripheral blood T lymphocytes was low in both studied groups. LPS-stimulated monocytes added to cultures of T lymphocytes induced increase in CD69 expression but significantly lower in children with idiopathic uveitis compare to healthy children.  相似文献   
992.
PURPOSE: To evaluate the efficacy of photodynamic therapy (PDT) with verteporfin in reducing the vision loss and progression of choroidal neovascularization (CNV) in patients with subfoveal CNV due to age-related macular degeneration (AMD). MATERIALS AND METHODS: 46 eyes of 46 patients with subfoveal, predominantly classic CNV caused by AMD and best-corrected visual acuity of 5/50 to 5/10 were treated with photodynamic therapy with verteporfin (Visudyne, CIBA Vision). Verteporfin was administered via intravenous infusion over 10 minutes. Fifteen minutes after the start of the infusion, a diode laser light at 689 nm (Opal Photoactivator, Coherent) was delivered over 83 seconds. Visual acuity and fluorescein angiography were performed before and after the treatment at 7 days and 1, 3, 6, 9 and 12 months after the initial-treatment. Retreatment in the same manner was applied if at follow-up examination fluorescein leakage from CNV was seen. Outcomes were compared with those of control group which consisted of 38 eyes of 38 patients of the same condition of the disease, not treated with any method. RESULTS: The lost of visual acuity was significantly reduced in the verteporfin--treated eyes compared--with controls. At the 12 month 73.91% eyes of PDT group versus 36.84% of control group (p < 0.001) lost fewer than 3 Snellen lines. The vision loss appeared to be more rapid in first 6 months of the study. During the study growth of CNV was diminished in PDT group compared with control group. CONCLUSIONS: Results show, that photodynamic therapy may be an effective method of treatment for predominantly classic subfoveal choroidal neovascularization caused by AMD. Further studies are needed to find the best modes of PDT procedure.  相似文献   
993.
PURPOSE: To determine differences between the predicted and postoperative refraction after cataract extraction with intraocular lens implantation in the eyes, which previous underwent vitrectomy. MATERIAL AND METHODS: Fifty three eyes of 52 patients underwent the analysis: twenty five in group I, nineteen in group II and nine eyes with previous scleral buckling in group III. All the eyes had ECCE and IOL with PMMA implantation after vitrectomy. In groups II and. III silicone oil tamponade was used and removed before cataract extraction. Thirty eyes of the control group K underwent cataract surgery and IOL implantation alone. The IOL power calculation was performed with SRK II formula. The predicted and postoperative refractions were compared. The follow-up was minimum 4 months (on average 15 +/- 12.71 months). RESULTS: The postoperative refractions were significantly shifted toward myopia than it was predicted--1.41 +/- 1.21 D in group I, -0.81 +/- 2.11 D in group II and -3.03 +/- 1.49 D in group III. In the control group K the difference was--0.07 +/- 0.91. CONCLUSIONS: Myopic shift of postoperative refraction after cataract surgery should be considered, when calculating the IOL power in the eye after vitreoretinal procedures.  相似文献   
994.
995.
The basic problem in decompression is the limit of maximum tolerable change of pressure after diving. Due to the number of parameters involved in decompression models (bottom time, ambient pressure, exposition profile, content of breathing mixtures, properties of inert gases) the number of possible solutions is theoretically unlimited. Since the beginning of modern decompression models the starting point has been direct saturation decompression using air. The generally accepted form of solution is the linear relation between tolerable pressure P2 after saturation exposition to pressure P1 described by the equation in the form P1 = P2 x A + B, where A and B are parameters obtained by experiments. Since the introduction of this equation values of parameters have been changing in order to decrease the rate of decompression illness. The aim of this study was to analyse and interpret the trend of those changes. Sixteen published models, including the one developed in our center, were compared and gradual change of parameters was identified. This trend should result in safer decompression systems.  相似文献   
996.
2,6-Dimethylaniline (2,6-DMA) and o-toluidine (o-TLD) together with their decomposition products are potential technological impurities of Pharmaceuticals used for local anaesthesia, in which lidocaine and prilocaine appear as active substances. Pharmacopoeial analytical methods for the determination of these impurities are little sensitive (from about 1 microg ml(-1)) and accurate and provide results which are difficult to interpret. Taking the above into account, a sensitive and specific amperometric method has been developed, which enables, after separation with the use of HPLC, an accurate determination of the content of 2,6-DMA and o-TLD in various pharmaceutical preparations. The determinations were performed at a glassy carbon electrode at a potential of +0.85 V. The limit of detection for both 2,6-DMA and o-TLD was 0.8 ng ml(-1). On the other hand, the limit of quantitation, considering a signal to noise ratio, was 1.5 ng ml(-1). The developed method allows to determine low concentrations of the impurities in question, which are hardly 1/120000 of the main substance. Preparation and determination of samples is carried out in a relatively short time, thus the method can be applied to routine investigations. Statistical evaluation of the obtained results shows that the accuracy and precision of the elaborated HPLC-ED method is good.  相似文献   
997.
The preparation of a number of new N-substituted derivatives of 1-acetyldibenzo-[e.h]-bicyclo[2.2.2]-octane-2,3-dicarboximide with an expected anxiolytic activity is described.  相似文献   
998.
Sterility and antibacterial activity of several antibiotics (including some penicillins and their salts, gramicidin and neomycin) subjected to sterilization by irradiation has been studied. The compounds in solid phase have been exposed to gamma irradiation in air atmosphere at room temperature, with a dose of 25 kGy, and afterwards they have been subjected to tests recommended by FP V (volume I, 1990) checking their sterility and activity. The results have shown that the majority of initial compounds have been to a slight degree contaminated by bacteria from the genera Bacillus and Micrococcus, the number of bacteria did not exceed 10(2) CFU, and fungi up to 10 CFU in 1 g of the compound. All compounds subjected to sterilization with a dose of 25 kGy were sterile and preserved the activity required by FP V. The decrease in activity observed for some compounds was always within the limits of FP specification. The results have proved that the penicillins analysed, gramicidin and neomycin can be sterilized by irradiation with a dose of 25 kGy, without any detrimental effect on their properties and antibacterial activity.  相似文献   
999.
Several applications of the COMSA were discussed including a series of the potential anti-HIV drugs and a series of dyes.  相似文献   
1000.
High performance size exclusion chromatography with fluorimetric detection for the determination of erythropoietin in pharmaceutical preparations has been developed. The applied chromatographic system has been enabled a quick estimation of the identity and contents of the studied compound. The method was validated and showed good validation data in terms of linearity, precision and repeatability. The validated method was successfully applied to the determination of erythropoietin content in commercially available preparations.  相似文献   
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