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71.
The effect of 2,3-dimercaptopropane sodium sulfonate on mercury retention in rats in relation to age
The effectiveness of DMPS (sodium 2,3-dimercaptopropane-1-sulfonate) in reducing inorganic mercury retention was studied in 2-, 6-, and 28-week-old albino rats. 203Hg was administered IP. The chelating agent DMPS was administered by IP injection at a dose of 250 mol/kg body weight three times, 1 day after 203Hg administration and at 24 h intervals thereafter. The whole body retention determined 1, 2, 3, and 6 days after 203Hg administration showed that DMPS decreased the body retention of mercury in all age groups, being about twice as effective in adult compared to suckling rats. The reduced effectiveness was due to the reduced efficacy of DMPS in reducing kidney retention in young animals. In other organs the effectiveness of DMPS was not age dependent. These and previous results obtained with different chelating agents and other metals indicate that age might be an important factor in chelation therapy in general. 相似文献
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Orkun Koban Ahmet Öğrenci Ezgi Ayçiçek Akar Ahmet Sadık Uyanık Mesut Yılmaz Sedat Dalbayrak 《Journal of orthopaedic science》2021,26(3):369-374
BackgroundIt is extremely difficult to treat spine disorders with stabilization in patients with rheumatoid arthritis. Because revision rates are significantly higher in rigid stabilization. To date, there is no data about patients with rheumatoid arthritis treated with dynamic stabilization. Our aim was to compare the radiological and clinical results of patients with rheumatoid arthritis who underwent lumbar rigid stabilization or dynamic stabilization with Polyetheretherketone rod (PEEK).MethodsPatients with degenerative lumbar spine disease with rheumatoid arthritis who underwent dynamic stabilization between 2013 and 2015 and rigid stabilization between 2010 and 2012 were evaluated radiologically for adjacent segment disease, proximal junctional kyphosis, system problem (nonunion, screw loosening, instrumentation failure, pull out). It was also compared according to both the revision rates and the Visual Analog Scale and Oswestry Disability Index scores at the 12th month and 24th month.ResultsThe difference of decrease in Visual Analog Scale and Oswestry Disability Index scores from preoperative to 12th month between patients who underwent dynamic stabilization and rigid stabilization was statistically insignificant. However, there was a significant difference of increase in Visual Analog Scale and Oswestry Disability Index scores between the 12th month and 24th month of patients who underwent rigid stabilization, compared with patients with dynamic stabilization. In patients with dynamic stabilization, the problems of instrumentation were seen less frequently. Revision rates were high in patients with rigid stabilization when compared the patients with dynamic stabilization.ConclusionRadiological and clinical outcomes in patients with rheumatoid arthritis operated with dynamic stabilization are more significant when compared to rigid stabilization. These patients have lower pain and disability scores in their follow up periods. Revision rates are lower in patients with dynamic stabilization. 相似文献
74.
Timotej Jagrič Christine Brown Tammy Boyce Vita Jagrič 《Health policy (Amsterdam, Netherlands)》2021,125(1):90-97
Policy-makers face pressures to improve lives and safeguard public finances sustainably. In this analysis, we estimate the economic importance of the health-care sector in 19 European national economies.We use input–output tables for the year 2010 and sectoral data to estimate a set of multipliers: simple, total, truncated, type I and type II multipliers for output, income, value-added, employment and import multiplier.The analysis reveals similarities in the economic importance of the health-care sector for the national economies of the observed countries. Results suggest prevailing positive effects on national economies (value-added, employment and household income) when spending on health-care sector products and services increases, especially in comparison to the effects of increases in spending in other sectors. The importance of the health-care sector is connected to countries’ levels of development; the benefits are especially promising in countries with lower levels of gross domestic product (GDP) per capita, where changes in the health-care sector have a larger impact on employment in the national economy than similar changes in more developed countries. The health-care sector therefore can play an important role as an instrument of economic policy. 相似文献
75.
Summary A new method is described which permits the measurement of membrane currents of thick muscle fibres (diameter 300 m or more) ofAstacus fluviatilis orBalanus balanus under voltage clamp conditions.The potential difference across a small patch of membrane (60–100 m in diameter) is controlled by connecting a voltage source across it with two external electrodes. One of them is connected to the fluid bathing the muscle fibre. The other, tubular one is in touch with the test area. The current flowing through the electrodes represents the sum of the membrane current flowing across the test area and the leak current flowing in the external fluid between the electrodes. In the first version of the method the leak current is limited by a circular sucrose gap around the test area. In the second, more elaborate method, the leak current is eliminated by a system of two concentric sucrose rings with a guard ring electrode between them. This method permits in addition the measurement of full sized action potentials in the test area.This work has been briefly reported in Cs. fysiol.17, 48 (1968). 相似文献
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78.
Action potentials of the rat diaphragm and their sensitivity to tetrodotoxin during postnatal development and old age 总被引:1,自引:0,他引:1
F. Vyskočil 《Pflügers Archiv : European journal of physiology》1974,352(2):155-163
Summary Using the microelectrode technique, parameters of action potentials obtained from the diaphragm muscle fibres were studied at 3, 7, 14, 30 and 90 days of age and on 28–30 month old rats. The maximum rate of rise was always greater at the end-plate zone than at the extrajunctional parts of muscle fibre at all ages examined. A maximum difference of 40% was found in animals aged 7–30 days. Sensitivity to tetrodotoxin (TTX) was maximal 3 days after birth at the extrajunctiona zone (5×10–8 M) and minimal at the end-plate zone (5×10–6 M). This difference declined during the postnatal life until it had disappeared in old rats. The greater resistance of the end-plate zone action potentials to TTX and their greater maximum rate of rise is not apparently connected with the presence of acetylcholine sensitivity. 相似文献
79.
80.
Davor Ježek Ljerka Šimunić-Banek Ružica Pezerović-Panijan 《Archives of toxicology》1993,67(2):131-140
The effects of exogenous testosterone on various testicular variables has become of increasing significance because of its potential use in male contraception. For this reason, high doses of two testosterone esters [testosterone propionate (TP) and testosterone enanthate (TE)] were used in a study of their influence on the morphology, length and curvature of the seminiferous tubules of the rat testis, and on cytological smears of the seminiferous tubules epithelium. TP was given for 14 days (3 mg/100 g body weight, i. m.) to assess the acute effects of testosterone on the seminiferous tubules. TE was administered for 60 days (in the same manner as TP) to study possible chronic effects on the rat testis. After TP and TE treatment the seminiferous tubule epithelium showed disorganization and desquamation of spermatogenic cells. In the TP-treated testes the tubules lined with Sertoli cells only were observed. The values for the length and curvature of seminiferous tubules of the TP- and TE-treated rats were significantly reduced (p<0.001). All these changes were observed earlier in the TP-treated than in the TE-treated animals. In cytological smears of the testis of the TP- and TE-treated rats an increase of vacuoles and residual bodies in Sertoli cell cytoplasm was noted. In addition, a reduction of spermatogenic cells, particularly sperms, was manifest in the smears after treatment. Large groups of Sertoli cells were seen in the smears from these testes.The study was supported by a Grant for Scientific Research No. 3-01-041 from the Ministry of Science, Technology and Informatics of the Republic of Croatia 相似文献