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1.
J. Rinat E. Korin L. Soifer A. Bettelheim 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,575(2):195-202
Calcium carbonate was deposited by electrochemical reduction of oxygen to hydroxyl ions at various carbon-based electrodes. Although some vaterite was observed during earlier stages of the electrodeposition, the predominant polymorph during later stages was calcite. The average crystal size reached a value of 15 μm after 10 h at a glassy carbon electrode but the crystal growth rate was substantially accelerated when oxygen was catalytically reduced. The same average size of the calcite crystals in this case (Pt/C electrode) was reached within a period of 1.5 h. Efficient removal of CaCO3 from water was demonstrated when using a porous aerogel carbon electrode and a potential sufficiently negative to promote reduction of water molecules within the pores. 相似文献
2.
本实验用C_(57)BL/6j小鼠CFU-GM集落形成的方法观察了三种CSF和氢化可的松、锂盐及硒盐对CFU-GM的影响及其对IFN的CFU-GM抑制作用的阻断作用。结果表明,三种CSF能部分拮抗IFN的CFU-GM抑制效应;微量的硒酸钠,碳酸锂均可刺激CFU-GM增殖,并使IFN200IU抑制的CFU-GM产率提高200%以上;微量的氢化可的松也能部分阻断IFN的CFU-GM抑制。 相似文献
3.
4.
Tarek Sadek Hakim Mazouz Hedi Bahloul Roxana Oprisiu Najeh El Esper Isabelle El Esper Francis Boitte Michel Brazier Philippe Moriniere Albert Fournier 《Nephrology, dialysis, transplantation》2003,18(3):582-588
BACKGROUND: Sevelamer hydrochloride was recently proposed as a phosphate binder to prevent hypercalcaemia in place of calcium alkaline salts in dialysis patients. So far, it has been evaluated only in patients receiving calcitriol, without comparison with CaCO(3) alone, although the latter was found to be as effective as the combination of calcitriol and Al(OH)(3) in suppressing parathyroid hormone (PTH) without inducing hypercalcaemia and to have a better lowering effect on serum phosphate. Moreover, this bile salt binder may decrease serum 25-OH vitamin D. Therefore, we compared for 5 months two strategies for controlling moderate hyperparathyroidism: CaCO(3) alone vs sevelamer in conjunction with measures to increase calcium balance. METHODS: Forty-two patients were randomized: 21 continued their treatment with 4.8 g/day CaCO(3) and 21 were switched to sevelamer (initial dose: 2.4 g/day, increased to 4.4 g/day). Each month, when serum-corrected calcium decreased below 2.30 mmol/l, dialysate calcium was increased or alphacalcidol was given at each dialysis session, according to serum PO(4) levels. The following parameters were monitored: serum Ca, PO(4), bicarbonate and protein, weekly; and serum PTH, 25-OH vitamin D and total, LDL and HDL cholesterol monthly. RESULTS: Except for higher serum phosphate at month 1, lower serum bicarbonate at month 2 and lower LDL cholesterol at month 5 in the sevelamer group, no difference was found between the two groups. Compared with baseline levels, PTH increased and 25-OH vitamin D decreased significantly in both groups, these two parameters being inversely correlated. CONCLUSIONS: Given comparable control of plasma calcium, phosphate and 25-OH vitamin D, PTH control is comparable in both strategies. Sevelamer does not induce greater vitamin D depletion than CaCO(3). The transient decrease of serum bicarbonate after discontinuation of CaCO(3) in the sevelamer group suggests a less optimal prevention of acidosis. The sevelamer-induced decrease in LDL cholesterol gives this drug a potential advantage in cardiovascular prevention. 相似文献
5.
Using the ELISA technique we have been able to quantify antibodies directed against actin and to follow the kinetics of antibody production. Specific anti-actin antisera have been raised in rabbits by immunization with chemically modified white muscle rabbit actin. Two or three dinitrophenyl groups linked per actin molecule were sufficient to break natural tolerance, while linkage of three phosphorylcholine groups to actin was not. 相似文献
6.
Marja Ala-Houhala Christer Holmberg Kai Rönnholm Aila Paganus Jarmo Laine Olli Koskimies 《Pediatric nephrology (Berlin, Germany)》1995,9(6):737-741
Alphacalcidol oral pulse therapy was given for secondary hyperparathyroidism to 22 children (mean age of 5.6 years) with renal insufficiency. At the beginning of the study, the glomerular filtration rate was <50% of normal, serum intact parathyroid hormone (PTH) was >100 ng/l and the serum phosphate and calcium concentrations were within the normal range. Alphacalcidol (0.5–3.0 g) was given orally thrice weekly in the evening and adjusted according to PTH, ionized calcium and phosphate concentrations. Serum PTH (mean ± SEM) decreased significantly from a pre-treatment level of 393±81 ng/l to 122±34 ng/l after 12 months, and stabilized at this level. Mean vitamin D metabolite concentrations were within the normal range. 1,25-Dihydroxyvitamin D did not increase during therapy, while PTH decreased. The estimated creatinine clearance remained almost unchanged (20±3 and 21±6 ml/min per 1.73 m2). Growth remained low normal (height standard deviation score –1.8±0.3 initially and –1.7±0.4 12 months later) and bone mineral density did not decrease. We concluded that feedback regulation of PTH with oral alphacalcidol pulse therapy is effective in the treatment of hyperparathyroidism in children with renal failure prior to dialysis. 相似文献
7.
The case of a patient with reappearing stupor, accompanied by auditory hallucinations and persecutory ideas during the periods and not with alternating excitement, is reported. After 24 years of neuroleptics medication with little effect, the lithium carbonate regimen was started, which showed a remarkable prophylactic effect. The implications of lithium carbonate treatment for recurrent psychosis are discussed. 相似文献
8.
碳酸锂对环磷酰胺的抑瘤及毒副作用的影响 总被引:6,自引:2,他引:6
观察碳酸锂(Li2CO3)对环磷酰胺(CP)的抑瘤作用和毒副作用的影响。按标准方法对每只小鼠进行肿瘤(肝癌H22、肉瘤S180)接种。Li2CO3[20、40mg/kg.dig,连续10天。CP(90、180mg/kg)一次iP。结果显示:Li2CO3与CP联合应用可显著提高抑瘤率,增加荷瘤鼠的外周血白细胞(WBC)数和降低骨磷嗜多染红细胞(PCE)的微核率(MNF)。提示Li2CO3能明显增强C 相似文献
9.
尼可刹米生产工艺改进 总被引:2,自引:0,他引:2
菸酸与二乙胺、三氯氧磷作用,再经氢氧化钠中和,加入纯碱使反应液中的产品与水分层,取代有机溶剂萃取工艺,简化了操作,降低了消耗. 相似文献
10.
Grzegorz Borkowski Agnieszka Martya Marta Dobrosielska Piotr Marciniak Ewa Gabriel Julia Gowacka Marek Jabrzykowski Daria Pakua Robert E. Przekop 《Materials》2022,15(17)
In this study, the influence of carbonate lake sediments (Polylactide/Carbonate Lake Sediments–PLA/CLS) on the mechanical and structural properties of polylactide matrix composites was investigated. Two fractions of sediments originating from 3–8 and 8–12 m were analysed for differences in particle size by distribution (Dynamic Light Scattering–DLS), phase composition (X-ray Diffraction–XRD), the presence of surface functional groups (Fourier Transform-Infrared–FT-IR), and thermal stability (Thermogravimetric Analysis–TGA). Microscopic observations of the composite fractures were also performed. The effect of the precipitate fraction on the mechanical properties of the composites before and after conditioning in the weathering chamber was verified through peel strength, flexural strength, and impact strength tests. A melt flow rate study was performed to evaluate the effect of sediment on the processing properties of the PLA/CLS composite. Hydrophobic-hydrophilic properties were also investigated, and fracture analysis was performed by optical and electron microscopy. The addition of carbon lake sediments to PLA allows for the obtention of composites resistant to environmental factors such as elevated temperature or humidity. Moreover, PLA/CLS composites show a higher flow rate and higher surface hydrophobicity in comparison with unmodified PLA. 相似文献