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21.
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,均匀制得的微晶的粒径大小约为2~4um,均匀微晶的结晶性好,纯度高。用均匀设计方法优化条件,制备的均匀的微晶平均粒径大小为2.09um,实验结果达到预测结果要求。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。 相似文献
22.
目的探讨D7S2 1位点在河北汉族人群分布的多态性 ,为DNA指纹数据库的构建及其法医学应用提供基础资料。方法应用MVR PCR方法和聚丙烯酰胺梯度凝胶电泳银染法对 12 4名河北汉族人群无关个体D7S2 1位点进行了快速检测 ,并进行数字编码。结果每一个体平均得到 3 6个数字编码 ,未发现任何两个无关个体所有编码相同 ,两无关个体 3 6个编码相同的机率为 3 .4 8× 10 -18。三种重复单位a 型、t 型和o 型出现的机率分别为 4 8.5 %、4 9.5 %和 2 .1%。该位点杂合度为 0 .9876,非父排除率为 0 .974 6,多态性信息含量为 0 .9872。结论D7S2 1位点在河北汉族人群中具有高度的多态性 ,聚丙烯酰胺梯度凝胶电泳银染法简便、快速 ,具有一定的实用价值 相似文献
23.
Silver nanoparticles (SNPs) can pass from the cell membrane and testicular blood barrier due to their small size, and by increasing oxidative stress they cause disorder in the male reproductive system. Kombucha is a traditional fermented drink with detoxification and potent antioxidant properties. We aimed to examine the protective effect of Kombucha against the damages due to SNPs on the testis tissue. In this experimental study, NMRI mice were randomly separated into four groups (n = 6), namely control (distilled water), SNPs (500 mg/kg), Kombucha extract (9 ml/kg) and SNPs + Kombucha, and were treated with gavage for 35 days. A significant decrease in testosterone level and total antioxidant capacity, and a significant increase in malondialdehyde concentration was observed in the SNPs group in comparison with the control group. Histological studies on the testis of mice treated with SNPs showed vacuolation, decrease in generational epithelium thickness, seminiferous tubules diameter, testis volume and the number of spermatozoa in lumen of the seminiferous tubule and increase in the volume of interstitial space while the mentioned parameters were improved in the SNPs + Kombucha group compared to the SNPs group. Kombucha reduces the adverse effects of SNPs on testis tissue and improves the function of the male reproductive system. 相似文献
24.
25.
微乳液反应法制备磺胺嘧啶银均匀微晶及其质量评价 总被引:1,自引:0,他引:1
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,并评价其质量。方法:利用磺胺嘧啶钠微乳和硝酸银微乳混合后反应的方法,制备磺胺嘧啶银均匀微晶,用透射电镜观察其形态和大小,以X-射线衍射分析、红外光谱、核磁共振、差热分析等手段检测磺胺嘧啶银均匀微晶各种理化特性。结果:磺胺嘧啶银均匀微晶的粒径大小约为2~4μm,均匀微晶的结晶性好,纯度高。体外抑菌实验表明该品比市售磺胺嘧啶银具有更好的抑菌效果。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。 相似文献
26.
Since the mid-1980s, cyanide in heap leach solutions and mill tailings ponds at gold mines in Nevada has killed a large but incompletely documented number of wildlife (>9,500 individuals, primarily migratory birds). This field investigation documents the availability of cyanide at a variety of typical Nevada gold mines during 1990 and 1991, describes wildlife reactions to cyanide solutions, and discusses procedures for eliminating wildlife loss from cyanide poisoning. Substantial progress has been made to reduce wildlife loss. About half of the mill tailings ponds (some up to 150 ha) in Nevada have been chemically treated to reduce cyanide concentrations (the number needing treatment is uncertain) and many of the smaller heap leach solution ponds and channels are now covered with netting to exclude birds and most mammals. The discovery of a cyanide gradient in mill tailings ponds (concentration usually 2–3 times higher at the inflow point than at reclaim point) provides new insight into wildlife responses (mortality) observed in different portions of the ponds. Finding dead birds on the tops of ore heaps and associated with solution puddling is a new problem, but management procedures for eliminating this source of mortality are available. A safe threshold concentration of cyanide to eliminate wildlife loss could not be determined from the field data and initial laboratory studies. New analytical methods may be required to assess further the wildlife hazard of cyanide in mining solutions. 相似文献
27.
目的观察吡哌酸锌软膏促进烧伤愈合的作用。方法用230℃的圆铁板造成大鼠背部烧伤,以不同浓度的吡哌酸锌及磺胺嘧啶银霜、磺胺嘧啶锌软膏、吡哌酸软膏、软膏基质每日涂药一次,连续15d。d16测量未愈合烧伤创面面积。结果吡哌酸锌软膏及磺胺嘧啶锌软膏均能明显促进创面愈合,两者之间无显著差异(P>0.05),但磺胺嘧啶银霜、吡哌酸软膏等促进创面愈合作用不明显(P>0.05)。结论吡哌酸锌软膏能明显促进烧伤创面的愈合。 相似文献
28.
F. Andreasen L. Elsborg S. Husted O. Thomsen 《European journal of clinical pharmacology》1978,14(1):57-67
Summary Sulfadiazine (SDZ) 800 mg and trimethoprim (TMP) 160 mg were given orally to 10 normal subjects and the concentration of SDZ and TMP in serum and urine was followed for 24 h. Both drugs showed a significant negative correlation between individual peak concentrations in serum and the body weight of the subject. Twelve hours after dosing the serum concentration was 12 to 25 µg/ml for SDZ and 0.3 to 1.1 µg/ml for TMP. Individual concentration ratios between SDZ and TMP in serum were 4.8 (1 h) – 145 (24 h), and in the urine the ratio was close to 6 throughout the 24 h collection period. The range of urinary concentrations was from 65 to 400 µg/ml for SDZ and from 13.8 to 93.4 µg/ml for TMP. The fraction acetylated SDZ/acetylated SDZ + SDZ was 21% during the 0–8 h period, 33% during the 8–15 h period and 41% during the 15–24 period. The average values for the notional volume of distribution, Vd, were 0.36±0.13 1/kg for SDZ and 1.39±0.25 1/kg for TMP. The average t1/2 was 15.2±7.4 h for SDZ and 7.4±1.9 h for TMP. Individual subjects showed a significant correlation between the serum clearance of TMP and SDZ (p<0.01) and also between the renal clearance of the two drugs (p<0.05). The serum clearance was significantly correlated with the renal clearance for TMP but not for SDZ. For SDZ Vd was significantly negatively correlated with the elimination constant; for TMP no such correlation was found. The serum clearance of SDZ was significantly correlated with the percentage of SDZ which was excreted as the (presumably) acetylated compound. The renal clearance of SDZ was independent of the serum concentration of SDZ. There was a highly significant negative correlation between the renal clearance and serum concentration of TMP, as well as for acetylated SDZ. The renal clearance of acetylated SDZ averaged more than six times that of unconjugated SDZ. With increased urine flow the renal clearances of TMP and SDZ were significantly increased. 相似文献
29.
Organization of nucleoli and nuclear bodies in osmotically stimulated supraoptic neurons of the rat 总被引:10,自引:0,他引:10
M Lafarga M A Andres M T Berciano E Maquiera 《The Journal of comparative neurology》1991,308(3):329-339
This study has analyzed variations in the number of nucleoli and nuclear bodies, as well as in their ultrastructural and cytochemical organization, after the osmotically induced activation of supraoptic nucleus (SON) neurons of the rat. The number of nucleoli and nuclear bodies and also the nucleolar size were determined on smear preparations of previously block-impregnated SON. The mean number of nucleoli per cell was 1.35 +/- 0.6 (mean +/- SDM) in control rats. No significant variations in this value were registered either in dehydrated or rehydrated rats. The mean nucleolar volume and the total nucleolar volume per cell showed a significant increase in dehydrated rats with respect to the controls, whereas these two parameters tended to return to control values in rats rehydrated after dehydration. The mean number of nuclear bodies per cell increased significantly from 0.56 +/- 0.50 (mean +/- SDM) in control rats to 1.54 +/- 1.1 after 6 days of dehydration. By electron microscopy, SON neurons displayed a reticulated nucleolar configuration. After the osmotically induced neuronal activation, there was an increase in the proportion of the total nucleolar area occupied by the granular component, and also a reduction in the mean fibrillar-center area. The most characteristic nucleolar features in rehydrated rats were the tendency for the granular component to be segregated and the occurrence of intranucleolar vacuoles. Ultrastructural cytochemistry with a specific silver method revealed a selective silver reaction on the coiled threads of the nuclear bodies--identified as "coiled bodies"--and on the nucleolar fibrillar components in all animal groups studied. Since nucleoli play a major role in ribosome biogenesis, a relationship between these nucleolar changes and the level of cellular activity of SON neurons is proposed. Furthermore, the response of nuclear "coiled bodies" to neuronal activation suggests their participation in the processing and transport of rRNA precursors. 相似文献
30.
磺胺嘧啶锌的HPLC测定 总被引:2,自引:0,他引:2
建立了磺胺嘧啶锌的HPLC测定法。以磺胺嘧啶为对照品,采用C18色谱柱,甲醇-水(30:70,用磷酸调至pH2.5)为流动相,检测波长270nm,流速1.0ml/min。在浓度40-300μg/ml范围内线性关系良好(r=0.9999)。平均回收率为101.1%,RSD为0.87%。 相似文献