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61.
肉鸡对不同形态锰源的生物利用率研究   总被引:9,自引:0,他引:9  
目的 : 研究肉仔鸡对不同形态锰源的相对生物学利用率。方法 : 将 62 4只 1日龄肉公鸡随机分为 1 3组 ,分别饲不添加锰的基础饲粮 (对照组 )或以不同锰化合物添加 60、1 2 0、1 80 mg/ kg锰的试验饲粮 2 1 d。结果 : 肉鸡生长性能各指标和腿病发生率以及肉鸡的跖骨灰锰含量、心肌细胞线粒体中 Mn SOD活性均未受到添加锰源以及锰源与锰水平互作的显著影响 ,但受到添加锰水平的显著影响。肉鸡心肌含锰量和 Mn SOD m RNA水平均未受到添加锰源与锰水平互作的显著影响 ,但受到添加锰源及添加锰水平的显著影响。其中中等和强络合强度有机锰源的生物学利用率明显高于无机硫酸锰和弱络合强度有机锰源。结论 : 中等和强络合强度的复合氨基酸锰对肉仔鸡的生物学利用率明显优于无机硫酸锰和弱络合强度的蛋氨酸锰  相似文献   
62.
为了降低焦化蜡油(CGO)-甲酸/H2O2选择性氧化体系中H2O2的无效分解速度,屏蔽重金属离子对H2O2分解的催化效应,考察了造纸行业中常用的硅酸钠、硅酸镁和乙二胺四乙酸(EDTA)等稳定剂和螯合剂的加入对有机溶剂抽提后CGO中含硫量的影响。实验结果表明,EDTA可以很好地和重金属离子螯合,氧化后CGO抽余油中硫含量大幅降低。  相似文献   
63.
溶栓治疗和神经保护治疗是缺血性脑卒中的两大药物干预策略,其中广义的神经保护治疗包括神经保护和神经修复两种方法,而目前存在的中西医结合缺血性脑卒中的药物干预策略可能也存在多层次、分阶段干预的特点,体现了祖国医学"同病异治"的原则,我们认为现有的缺血脑保护方法主要针对缺血性脑卒中的不同发展阶段,而神经修复的研究,尤其是中医药促进神经干细胞再生的研究,可能蕴涵着巨大的发展潜力和无限商机.  相似文献   
64.
In Part I of this review series, an overview was presented on what the basic properties of supercritical fluids are and how they can, and are being used in many of today's industries as solvents for extraction, chromatography and reaction. A good part of this overview detailed the kinds of equipment needed, and techniques on how to use them for optimal performance. Part II of this series will delve into specific applications of supercritical fluid technology as it relates to aspects of medical isotope processing. The reader will note that very few applications of this technology to Nuclear Medicine have been published. Many potential applications cited within the context of this review derive from preliminary studies carried out in the author's laboratory. These examples are presented to spark interest in future developments of this nature. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
65.
The aim of the present study was to evaluate the combined application of different bioabsorbable materials for healing of residual peri‐implant defects after placement of non‐submerged implants into fresh extraction sockets. Second and third mandibular premolars were extracted from 10 Beagle dogs, the coronal part of the distal sockets were surgically enlarged and this was followed by immediate placement of specially designed hollow‐screw non‐submerged dental implants. For each animal, the coronal peri‐implant defects were further treated with one of the 4 following procedures: 1) no treatment, control site: 2) grafting with porous hydroxyapatite (HA); 3) collagen membrane tightly secured around the implant and over the defect and 4) grafting with HA covered with a collagen membrane. After 16 weeks of healing, specimens were removed from the mandibule and prepared for a histomorphometric evaluation. The bone-to-implant contact length (BIC) was measured and compared amongst the different treatment modalities. In the defect area, the irregular bone regeneration was similar between all the treatment procedures ( P >0.10). In the sites covered with a collagen membrane alone, the total BIC (47%) was greater than in control sites (28.7%. P <0.05) or sites grafted with HA (22.2%, P <0.02). Total BIC in sites treated with the HA‐membrane combination (43%) was only significantly different from sites treated with HA ( P <0.10). It is concluded that the use of bioabsorbable materials results in a limited increase of osseointegration when used in conjunction with immediate placement of non-submerged implants, although the principle of the one stage surgical approach can be maintained.  相似文献   
66.
本文探讨了菊科9种植物和地胆草的4种对口商品药材基因组DNA提取与纯化的原理、方法通过对3种常用植物基因组DNA提取方法(CsCl梯度超速离心法、CTABCsCl梯度超速离心法和CTAB微量提取法)的条件摸索在DNA产率、纯度以及提取纯化过程中影响PCR扩增因子方面进行比较,认为CTAB微量提取法是植物类药材基因组DNA一种比较省时、有效、经济的提取方法  相似文献   
67.
Purpose: To determine if adequate anaesthesia and akinesia could be obtained using an inferonasal quadrant sub-Tenons anaesthesia for cataract surgery.
Methods: The sub-Tenons method of local anaesthesia was used in 50 patients undergoing extracapsular cataract extraction and lens implantation. The technique followed was that described by JD Stevens in his study of 50 patients. Posterior sub-Tenons space was approached through a conjunctival incision in the inferonasal quadrant and the anaesthetic solution delivered by an irrigating cannula. The patients were assessed for residual ocular movements just before surgery. Effectiveness of anaesthesia was assessed during surgery using a verbal pain rating score. Scoring was based on the concept of a visual analogue pain score chart.
Results: Total akinesia was obtained in 20% patients and total anaesthesia in 24% patients. The remainder of the patients had adequate akinesia and anaesthesia to proceed with and complete the surgery.
Conclusion: This method provides satisfactory anaesthesia for cataract surgery.  相似文献   
68.
Summary A specific radioimmunoassay for the quantitative measurement of ACTH 4-10 and a procedure for its extraction from plasma have been developed.Its pharmacokinetics was studied in eight healthy male volunteers given ACTH 4-10 125 µg/kg body weight as a bolus i.v. injection, by infusion and intranasally. Following the i.v. bolus, plasma levels rapidly declined biexponentially, with half-lives of 0.39±0.05 min for the -phase and 3.84 ± 1.5 min for the -phase (mean±SD). The constant rate i.v. infusion yielded steady-state levels between 0.74 and 5.06 ng/ml plasma. Administered as intranasal spray, absorption of intact ACTH 4-10 was low and variable (maximal bioavailability 7.6%).The results are discussed in relation to the dose-dependent effects of ACTH 4-10 on the auditory evoked potential.  相似文献   
69.
A high-performance liquid chromatographic (HPLC) method is described for the assay of the active metabolite [1-(2-pyrimidinyl)piperazinel of buspirone, an anxiolytic agent, in rat plasma.

The method is based on the use of ion-pair HPLC coupled to a liquid—solid extraction scheme. Samples of rat plasma (2 ml) with internal standard (1-phenylpiperazine), adjusted to pH 10.5 with borate buffer, were loaded on to a preactivated C-18 cartridge. The metabolite and the internal standard were eluted with 5 ml of methanol and injected on to a reversed-phase 10-μm Spherisorb ODS-2 column. The column was eluted with a mobile phase of 0.005 M sodium lauryl sulphate in citrate buffer (pH 3.6)-acetonitrile (65:35, v/v) at 2 ml min−1. Detection was carried out at 248 nm. The recovery of the metabolite was 55%. The method was applied to the determination of the metabolite in rat plasma after oral dosing (25 mg kg−1) of the parent compound.  相似文献   

70.
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