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131.
在广泛文献检索基础上,文章对生铁落的种属、成分、药理及临床应用等进行了概述,为深入开发利用提供科学资料。  相似文献   
132.
目的 合成地拉罗司并对工艺进行优化研究。方法 以水杨酸为原料,经与二氯亚砜氯化、水杨酰胺脱水环合和对羧基苯肼开环重排3步得到口服铁螯合剂地拉罗司。结果 地拉罗司合成总收率为59.36%。结论 对工艺进行了改进,提高了地拉罗司合成收率。  相似文献   
133.
An approach toward treatment of tumors involving the optic apparatus is presented. When tumors cause mass effect, microsurgical excision or debulking is generally recommended. Radiosurgery has been controversial yet advances in imaging and high speed computer planning allow treatment of lesions involving the optic apparatus with low morbidity. Microsurgical and radiosurgical approaches to tumors involving the globe, orbit, suprasellar region and third ventricle are discussed. Gamma Knife radiosurgery for choroidal melanomas spares orbital excenteration. We have used a marginal dose of 20–25 Gy for choroidal melanomas and generally limit the optic nerves and chiasm to less than 10 Gy in other cases. The effective dose for cavernous hemangiomas remains unclear, however we have had success with marginal doses in the range of 16–20Gy. Lower doses may prove successful yet better spare vision in cases where vision is useful. Our combined microsurgical and radiosurgical approach to tumors involving the apparatus has had an excellent rate of sparing vision, a low overall morbidity and excellent success.  相似文献   
134.
Soaking of cereal grains has been suggested as a method to reduce their phytate content and hence increase their mineral availability. Whole and milled wholegrain, normal and low phytate sorghum and normal maize were studied. Soaking of unmilled sorghum and maize did not result in substantial reductions in phytate or mineral contents. With milled grains, phytate solubilisation was somewhat greater in maize than in sorghum after a short (1?h) soaking period but not after 6–12?h of soaking when practically all phytate had been solubilised. Also, with milled, low phyate sorghums, phytate solubilisation was not substantially higher than in their null controls. Soaking milled grain substantially reduced mineral contents and Ca?×?phytate:zinc molar ratios. However, the loss in soluble minerals could have a greater negative effect on mineral availability, compared to the positive effect of the phytate reduction. Thus, soaking does not seem to be a viable household method to improve sorghum and maize mineral availability.  相似文献   
135.
Recent years have witnessed impressive advances in our understanding of iron metabolism. A number of studies of iron disorders and of their animal models have provided landmark insights into the mechanisms of iron trafficking, distribution and homeostatic regulation, the latter essential to prevent both iron deficiency and iron excess. Our perception of iron metabolism has been completely changed by an improved definition of cellular and systemic iron homeostasis, of the molecular pathogenesis of iron disorders, the fine tuning of the iron hormone hepcidin by activators and inhibitors and the dissection of the components of the hepcidin regulatory pathway. Important for haematology, the crosstalk of erythropoiesis, the most important iron consumer, and the hepcidin pathway has been at least partially clarified. Novel potential biomarkers are available and novel therapeutic targets for iron‐related disorders have been tested in murine models. These preclinical studies provided proofs of principle and are laying the ground for clinical trials. Understanding iron control in tissues other than erythropoiesis remains a challenge for the future.  相似文献   
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Both iron deficiency and hyperglycemia are highly prevalent globally for pregnant women. Iron supplementation is recommended during pregnancy to control iron deficiency. The purposes of the review are to assess the oxidative effects of iron supplementation and the potential relationship between iron nutrition and gestational diabetes. High doses of iron (~relative to 60 mg or more daily for adult humans) can induce lipid peroxidation in vitro and in animal studies. Pharmaceutical doses of iron supplements (e.g., 10× RDA or more for oral supplements or direct iron supplementation via injection or addition to the cell culture medium) for a short or long duration will induce DNA damage. Higher heme-iron intake or iron status measured by various biomarkers, especially serum ferritin, might contribute to greater risk of gestational diabetes, which may be mediated by iron oxidative stress though lipid oxidation and/or DNA damage. However, information is lacking about the effect of low dose iron supplementation (≤60 mg daily) on lipid peroxidation, DNA damage and gestational diabetes. Randomized trials of low-dose iron supplementation (≤60 mg daily) for pregnant women are warranted to test the relationship between iron oxidative stress and insulin resistance/gestational diabetes, especially for iron-replete women.  相似文献   
140.
Heart failure (HF) is highlighted by its burdening symptom-limited exercise capacity and recurrent hospitalizations. Despite substantial advances regarding disease-modifying drugs in HF with reduced ejection fraction, additional therapeutic strategies to improve quality of life are invaluable. Currently, iron deficiency (ID) is overwhelmingly recognized in over 30% to 50% of patients with stable chronic HF, which worsens prognosis. The established pathophysiological mechanisms of progressive HF may be intertwined with increasing myocardial iron scarcity, wherein one begets the other. Most importantly, ID constitutes a novel target for symptom relief in carefully selected patients. In this regard, intravenous iron may be a safe and efficacious intervention, potentially reducing HF hospitalizations. We discuss the evidence and gaps in knowledge concerning iron therapy in HF and propose a practical, comprehensive, clinically oriented algorithm for timely adequate iron replenishment in different clinical scenarios. Finally, we further debate imperative decision-making before intervention and the drawbacks of such a strategy.  相似文献   
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