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51.
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
52.
Jarmila Kruseová Jelena Černíková Marina Zámečníková Lucie Hřivnová Stanislava Koloušková Michaela Čepelová Edita Kabíčková Václav Čapek Aleš Lukš Tomáš Eckschlager 《Andrologia》2021,53(1):e13853
The objective of this study was to compare semen quality (sperm density, progressive motility and spermia) between long-term childhood cancer survivors and a control group of males. The second objective was to correlate the semen analysis of the survivors with cancer treatment and endocrine status. The semen quality of 143 survivors (median age, 23.6 years) was compared to 200 men (median age, 27.9 years) who had not been diagnosed with cancer. The cancer-related risk factors and gonadotrophin levels were compared. Overall, 65% of the survivors had abnormal semen analysis compared to 26.5% of the controls (p < 0.0001). Survivors with nonaspermia had lower sperm density than the controls (p < 0.001). Other observed correlations were not significant. Survivors who were treated with alkylating agents were more likely to have abnormal semen analysis (p < 0.008). Follicle-stimulating hormone and luteinising hormone levels were significantly elevated (p < 0.0001) in survivors with abnormal semen analysis. The semen quality parameters, except for low sperm density, did not differ in survivors with nonaspermia compared to the controls. The risk factors included treatment with alkylating agents. Elevated gonadotrophin levels correlated with abnormal semen analysis. All cancer survivors should be made aware of the possibility of suffering from cancer treatment-related infertility. 相似文献
53.
Mehmet Celik Yusuf Yilmaz Muzaffer Kahyaoglu Ayhan Kup Yusuf Bilen Regaip Zehir 《Journal of cardiac surgery》2021,36(1):336-338
Right ventricular (RV) perforation is a rare but life‐threatening complication of pericardiocentesis and is usually treated surgically. We presented a case of RV free wall perforation, which occurred during pericardiocentesis and tried to be closed percutaneously with the Amplatzer vascular plug‐III (AVP‐III) device. The occluder device sealed the perforation, but it was in an insecure position; therefore, the patient underwent surgical repair. As an AVP‐III device, with a middle disk thicker than the RV myocardium, it may cause the RV myocardium to stretch outwards, so it should not be used for the treatment of RV perforation by the transcatheter way. 相似文献
54.
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
55.
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
56.
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58.
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
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60.
Young semi-domesticated pigeons captured or hatched from eggs gathered in Bratislava during 1989–1991 were examined for complement fixing antibodies to Chlamydia psittaci and agglutinating antibodies to Coxiella burnetii. Antibodies to Ch. psittaci were present in 76% of birds younger than 24 h, in 47.7% between 1 and 10 days of age and in 12% of nestlings over 10 days old. Antibodies to Ch. psittaci were also detected in crop milk of 4.1% of 1 to 10 day old birds and in 4.5% of specimens older than 10 days. Antibodies to C. burnetii were not found in juvenile birds under 24 h old, but antibodies against this agent were present in 16.4% birds between 1 and 10 days old and in 18% over 10 days old. Antibodies to C. burnetii were also detected in crop milk collected from crops of 2% of the young birds between 1 and 10 days. 相似文献