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21.
建立大体积进样,离子色谱法(IC)测定饮用水中不同数量级F-,BrO3-,Cl-,Br-,NO2-,NO3-,SO4-等7种无机阴离子的新方法。采用离子色谱碳酸盐等度淋洗系统,高容量色谱分析柱AS-23,DS5电导检测器,500μL定量环直接进样分析饮用水中7种无机阴离子的保留时间等,并通过峰面积法定量各种阴离子含量。该法各离子线性相关性好(R>0.999 0),精密度高(RSD<3.6%),准确度好(平均回收率96.5%~102.4%),检出限低(3.56~6.74μg/L,以500μL进样量计算)。可同时测定饮用水中不同数量级浓度的7种无机阴离子,检出限低,操作简便,快速准确,不仅能够满足水质监测要求,而且大幅提高检测效率。 相似文献
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Deborah C. Silverstein DVM DACVECC Janet Aldrich DVM Steve C. Haskins DVM MS DACVECC DACVA Kenneth J. Drobatz DVM MSCE DACVECC DACVIM Larry D. Cowgill DVM PhD DACVIM 《Journal of Veterinary Emergency and Critical Care》2005,15(3):185-192
Objective: To determine the continuous changes in blood volume in response to fluid administration using an in‐line hematocrit monitor. Design: Prospective study. Setting: Research laboratory. Animals: Four healthy dogs. Interventions: Each dog received intravenous boluses of 80 mL/kg of 0.9% saline (S), 4 mL/kg of 7.5% saline (HS), 20 mL/kg of dextran 70 (D), 20 mL/kg of hetastarch (HES), or no fluids (control, C) on separate occasions. Fluids were administered at 150 mL/min in the S, D, and HES groups, and at 1 mL/kg/min in the HS group. Measurements and main results: Blood volume changes were measured every 20 seconds for 240 minutes using an in‐line hematocrit monitor. There was a rapid rise in blood volume during all infusions. Immediately after the administration of crystalloid fluids, the rapid rise in blood volume ceased. Subsequently, there was a steep decline in blood volume for 10 minutes, and a slower decline thereafter. In contrast, the rise in blood volume continued for at least 10 minutes after the infusion of the colloids was complete, and a plateau was observed for the remainder of the experiment. The blood volume effect, as measured by area under the curve, was significantly greater in the saline group than the other groups during the infusion time and for the 0–240 minutes time period. The areas under the curve for the two colloid solutions were not significantly different from each other during any time periods. The percent increase in blood volume immediately following the infusions was 76.4±10.0 in the S group, 17.1±3.2 in the HS group, 23.0±10.5 in the D group, and 27.2±6.4 in the HES group. At 30 minutes from the start of the infusion, the mean percent increases in blood volumes were 35.2±9.3 in the S group, 12.3±0.9 in the HS group, 35.9±7.3 in the D group, and 36.8±6.5 in the HES group. At 240 h post‐infusion, the mean percent increases in blood volume were 18.0±9.7 in the S group, 2.9±6.1 in the HS group, 25.6±16.1 in the D group, and 26.6±8.6 in the HES group. The C group had a mean percent change in blood volume of ?3.7±3.4 at the end of the experiment. Conclusions: This study indicates that the rapid administration of saline at clinically relevant doses leads to the largest immediate increase in blood volume, although this change is transient because of rapid redistribution of the fluid. Despite a brief increase in blood volume that was almost 3 times the volume administered, hypertonic saline led to the smallest increase in blood volume post‐infusion. The synthetic colloid solutions increased the blood volume by an amount greater than that infused and the effect was sustained for a longer period of time than seen following crystalloid administration, but the maximum increase in blood volume was significantly less than saline. The measurement of continuous changes in blood volume, using an in‐line hematocrit monitor, was a useful means of assessing the dynamic effects of fluid administration in dogs in a research setting. 相似文献
24.
干旱沙区农田防护林营建模式与经营评价研究 总被引:5,自引:1,他引:5
通过对干旱沙区人工绿洲农田防护林林木生长量的调查测定和样本树干解析数据,揭示了林木生长规律,建立了树干材积模型,为农田防护林合理更新提出了科学依据。利用相关依据指标,对现有农田防护林的营建模式进行了评价,提出了新的更新模式。 相似文献
25.
The object of this study was to develop a simple method for accurately calculating the volume of bovine claws under field conditions. The digits of 30 slaughterhouse beef cattle were examined and the following four linear measurements taken from each pair of claws: (1) the length of the dorsal surface of the claw (Toe); (2) the length of the coronary band (CorBand); (3) the length of the bearing surface (Base); and (4) the height of the claw at the abaxial groove (AbaxGr). Measurements of claw volume using a simple hydrometer were highly repeatable (r(2)= 0.999) and could be calculated from linear measurements using the formula:Claw Volume (cm(3)) = (17.192 x Base) + (7.467 x AbaxGr) + 45.270 x (CorBand) - 798.5This formula was found to be accurate (r(2)= 0.88) when compared to volume data derived from a hydrometer displacement procedure. The front claws occupied 54% of the total volume compared to 46% for the hind claws. 相似文献
26.
复方黄柏颗粒剂在小鼠体内的药代动力学 总被引:1,自引:0,他引:1
为探讨复方黄柏颗粒剂有效成分-盐酸小檗碱在小鼠体内的药动学特征,按25 g/kg(相当于盐酸小檗碱10.95 mg/kg)的剂量经口给予小鼠复方黄柏颗粒剂,用高效液相色谱法检测用药后不同时间血浆中盐酸小檗碱的质量浓度,研究在小白鼠体内的药物动力学。结果表明口服复方黄柏颗粒的有效成分-盐酸小檗碱在小鼠体内的药时数据符合开放性二室模型,动力学方程为C=17.8e-0.859 81t 14.51e-0.636 1t。主要药代动力学参数:t1/2α为(0.81±0.07)h,t1/2β为(5.25±2.96)h,t1/2Ka为(0.76±0.05)h,AUC0→∞为(3.389 3±0.437 4)mg.L-1.h,CL/F为(3.281 8±0.446 3)L/h,Vd/F为(13.65±22.38)L/kg,Tpeak为(1.617 19±0.056 50)h,Cmax为(1.149 98±0.056 04)μg/mL。 相似文献
27.
GIOVANNA BERTOLINI TOMMASO FURLANELLO DAVIDE DE LORENZI MARCO CALDIN 《Veterinary radiology & ultrasound》2006,47(5):444-448
We conducted a retrospective study in presumed normal dogs to determine the adrenal gland attenuation and volume values. Multidetector computer tomography (MDCT 16) analysis of the gland was carried out in 48 adult dogs without evidence of adrenal gland disease that underwent CT examination for acute spinal injuries. The mean nonenhanced attenuation value +/- SD of the left adrenal gland was 36.0 +/- 5.3 HU (range: 22.0-42.0 HU). The mean nonenhanced attenuation value +/- SD of the right gland was 34.3 +/- 7.0 HU (range: 20.4-48.6HU). The mean enhanced attenuation value +/- SD were: left gland 101.5 +/- 10.6HU (range: 86.8-128.0 HU), and right gland 97.4 +/- 12.4 HU (range: 58.9-123.6 HU). The mean CT volume +/- SD were: left gland was 0.60 cm3 (range: 0.20-0.95; SD 0.17), and right gland (0.55cm3, range: 0.22-1.01; SD 0.19). Attenuation values and volume data were related to age, weight, and gender, using ANOVA. There was no statistically significant difference between the left and right side or in adrenal measurements, because of body weight class effects. The animal effect was the most important source of variation for all adrenal measurements. Based on our study, CT is an effective method for assessing adrenal characteristics in the dog. Normative CT data are provided to allow estimation of normal adrenal gland size and volume. 相似文献
28.
The relationship between the physicochemical properties (molar volume, partition coefficient, and dissociation constant) of slow-acting systemic postemergence xenobiotics and their uptake and translocation to the sites of action was investigated using the nonlinear, dynamic simulation model ERMESSE. When the pKa was held constant at 4.0, the model enables the prediction of the uptake of a systemic xenobiotic as a function of its partition coefficient and molar volume. The model also considered the effects of the physicochemical properties of a systemic xenobiotic on its long-distance translocation within the vascular tissues. For instance, when the log Kow and pKa were held constant at 1.5 and 6.0, respectively, the model predicted a higher translocation rate (55%) for molecules with a small (e.g., MV = 100 cm3 mol−1) as opposed to a large (e.g., MV = 300 cm3 mol−1, 33%) molar volume. In addition, the theoretical predictions from the ERMESSE model showed that any xenobiotic with a molar volume not exceeding 300 cm3 mol−1 could provide an uptake ?50% and a translocation rate ?25% when its log Kow is between −0.5 and 2.5 and its pKa is between 0.0 and 8.0. 相似文献
29.
通过对2000年、2002年野生动植物进出口贸易额的比对分析,对野生动植物进出口贸易中有关贸易额、贸易价格、中医药、海关记录数据等主要问题进行了具体分析,并对加强野生动植物的进出口管理提出几点建议:规范海关记录、监管标准;加强大宗贸易的审查和管理;推广限额、限价管理;进行全国野生动植物贸易调查;争取某些产品的特惠税制度等。 相似文献
30.