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1.
采用水蒸气蒸馏法、有机溶剂萃取法、CO2超临界萃取法3种提取方法提取组培百里香精油,比较分析精油得率、精油化学成分以及相对含量,以期得出最佳提取方法。结果表明:水蒸气蒸馏法提取的百里香精油得率为O.21%,主要化学成分为:百里酚(36.53%)、间伞花烃(14.13%)、松油烯(8.09%)和石竹烯(4.14%);有机溶剂萃取法提取的精油得率为0.19%,主要化学成分为:1,2-苯二甲酸-单-2-乙基己基酯(55.23%)、百里酚(873%)、松油烯(5.23%);CO2超临界萃取法提取的精油得率为0.27%,主要化学成分为:百里酚(26.68%)、3-苯基-2-丙烯酸-甲酯(21.55%)、间伞花烃(9.69%)。从精油得率、精油质量以及精油主要化学成分综合比较3种方法,水蒸气蒸馏法是提取百里香精油的最佳方法。  相似文献   

2.
广西何首乌中微量元素的原子吸收光谱分析   总被引:2,自引:0,他引:2  
程碧桃   《广西植物》1996,16(4):359-361
用原子吸收光谱法测定了广西何首乌中4种微量元素,考查了方法的精密度和准确度,变异系数为3.1%~4.3%,回收率为94.5%~105.1%。  相似文献   

3.
目的:探讨腹部X线与CT扫描鉴别急性肠梗阻的准确性,为临床诊断提供参考。方法:选取2011年8月-2013年8月我院收治的66例急性肠梗阻患者的临床资料进行回顾分析。所有患者均经手术活检或病理诊断证实为急性肠梗阻。术后患者均行腹部X线及CT扫描检查,对两种方法判断肠梗阻的发生、梗阻部位、类型及病因与手术病理结果进行比较,评价并分析两种检查方法的准确率。结果:66例肠梗阻患者中,X线检出率为89.39%,CT检出率为95.45%。X线诊断小肠梗阻准确率为72.10%,CT为86.05%;X线诊断结肠梗阻准确率为69.57%,CT为86.96%。X线诊断肿瘤准确率为69.57%,CT为86.96%;X线诊断肠粘连准确率为67.86%,CT为82.14%;X线诊断肠套叠准确率为60.00%,CT为80.00%;X线诊断单纯性机械性肠梗阻准确率为78.72%,CT为82.98%;X线诊断绞窄性肠梗准确率为73.68%,CT为78.95%。CT对肠梗阻部位、病因及类型的诊断准确率高于腹部X线片,差异具有统计学意义(P〈0.05)。结论:腹部X线与CT用于诊断急性肠梗阻具有较高的准确率,但CT对于肠梗阻部位、梗阻类型及梗阻病因的诊断优于X线片。  相似文献   

4.
目的:建立测试黄连素片中盐酸小檗碱含量的高效液相方法,并对此方法进行系统的方法学验证,以确保应用该方法测试的结果准确、可靠。方法:采用色谱柱:Agilent TC-C18柱(4.6 mm ×150 mm,5μm,Agilent,美国),流动相:乙腈-0.05 mol/L磷酸二氢钾溶液(45∶55,含5%的0.05 mol/L庚烷磺酸钠溶液),检测波长为265 nm。结果:盐酸小檗碱在2.5~80μg/mL范围内线性关系良好,得到线性回归方程为Y=421 .5X+17.32,相关系数为0.9997(n=6);低、中、高浓度批内精密度的RSD值分别为0.30%、0.58%、0.30%,批间精密度的RSD为0.80%;重复性RSD为0.27%;低、中、高浓度的加样回收率分别为99.66%、99.88%、99.98%;供试品溶液室温放置8h稳定,RSD为0.41%。结论:本方法测定黄连素片中盐酸小檗碱的含量准确、可靠,操作简单、用时短,可用于黄连素片中盐酸小檗碱的含量测定。  相似文献   

5.
本文报道应用多肽抗体谱印迹法检测风湿性疾病患者的ENA抗体,该法一次可检测7种抗体。应用本法检测SLE85例,其Sm抗体阳性率为20.0%,u1-RNP抗体为41.1%,SS-A抗体为10.5%SS-B抗体为3.5%,抗核糖体为7.0%。检测DLE6例,其山u1-RNP抗体阳性率为33.0%。检测PM/DM15例,其u1-RNP抗体阳性率为13.0%,Jo-1抗体为14.0%。检测RA48例,其u1-RNP抗体的阳性率为33.3%。检测SS21例,其SS-A抗体阳性率为43.0%,SS-B抗体为38.0%,检测PSS9例,其Scl-70抗体阳性率为22.0%。检测MCTD10例,其u1-RNP抗体阳性率为50.0%。健康人对照100例,7种抗体均为阴性。显示应用多肽抗体谱印迹法检测结果与国内其它方法所测得结果基本一致,但可检测的抗体种类多于其它方法。  相似文献   

6.
目的了解医务人员手部卫生状况,制定改进措施,预防医院感染。方法回顾性分析东南大学附属中大医院2007年1月至2010年12月医务人员手卫生监测资料1586份。结果医护手监测合格率为89.28%,医生手监测合格率为86.94%,护士手监测合格率为93.09%;重点病区医护手监测台格率为91.98%,普通病区医护手监测合格率为87.06%;该院医护手监测合格率为90.64%,进修、实习医护手监测合格率为88.17%,手部检出细菌184株,葡萄球菌属占49.46%,阳性杆菌占14.67%。结论医务人员对手的清洁与消毒仍缺乏足够的认识,应加强医务人员手卫生培训与监督,提高医务人员手卫生合格率。  相似文献   

7.
98年2194份呼吸道标本病原体分析   总被引:4,自引:0,他引:4  
目的 了解本地区呼吸道感染的病原体。方法 采用回顾性调查方法对我院1998年1月~12月呼吸道标本规培养结果进行全面分析。结果 病原体阳性培养率为32.36%,其中G-杆菌占73.52%,G+菌占12.68%,霉菌占13.80%;在病原体种类中前五位依次为,绿脓杆菌占25.07%,肺炎克雷伯杆菌占17.04%,霉菌占13.80%,葡萄球菌占8.17%,鲍鳗不动杆菌占6.20%。结论 本地区呼吸道感  相似文献   

8.
黑曲霉几丁质和壳聚糖的研究   总被引:26,自引:0,他引:26  
曹健  殷蔚申   《微生物学通报》1995,22(4):200-203
通过正交试验确定黑曲霉的最佳培养条件。由培养的黑曲霉湿菌体制备几丁质,最经济的方法是电解法;制备壳聚糖则采用间歇提取法,所得干燥壳聚糖产品的壳聚糖含量为92.29%,游离氨基为96.11%,1%壳聚精的1%醋酸溶液运动粘度为5.33x10-6/s,粘均分子是为8.024x10,灰分为9.24%,产品得率为9.72%,探讨了从柠檬酸厂废弃酸渣中分离黑曲霉菌丝体的方法,得率为30%左右。  相似文献   

9.
采用国产链霉亲和素直接包被塑料板孔,生物素标记抗体,建立的竞争酶联免疫吸附试验的方法测定血中地高辛浓度,其测定灵敏度为0.964μg/L最低检测限为0.2251μg/L,测定三份低,中、高浓度的血甭标本,批内变异系数为8.9%、5.9%、2.4%;批间变民系数为15.8%、10.1%、9.2%,测定回收率在89.1-107.22%之间,此法与FPIA方法相关良好。  相似文献   

10.
目的探讨红鲫实验动物的营养需要、科学配制红鲫饲料。方法用常规方法测定红鲫幼鱼、红鲫成鱼的含肉率及肌肉营养成分。结果红鲫幼鱼、红鲫成鱼的含肉率为46.34%、42.35%;红鲫幼鱼、红鲫成鱼肌肉(鲜样)中分别含水分79.11%、78.49%,粗蛋白质12.47%、14.72%,粗脂肪6.95%、4.37%,粗灰分1.01%、1.41%,无氮浸出物0.47%、1.07%,能量5.65kJ/g、5.24kJ/g,其E/P值(能量蛋白比)为45.32kJ/g、35.69kJ/g。结论红鲫幼鱼、红鲫成鱼含肉率、肌肉营养成分有一定差异。  相似文献   

11.
紫锥菊属三种植物的抗氧化性能研究   总被引:2,自引:0,他引:2  
采用分光光度法和电子顺磁共振法对紫花松果菊、狭叶松果菊、白花松果菊乙醇提取物的抗氧化性能进行了分析研究。结果表明,狭叶松果菊、白花松果菊、紫花松果菊提取物对羟自由基的清除率分别是76.4%、68.1%、61.5%,对超氧阴离子自由基的清除率分别是80.6%、85.7%、74.2%,对香烟烟气自由基的平均清除率分别是31.8%、19.4%、25.1%。  相似文献   

12.
为探索一个灵敏、简便、快速的定量检测A/C群脑膜炎球菌多糖疫苗中乳糖含量的方法,对两种化学法进行了分析和比较。两种化学方法分别采用间苯二酚显色法和苦味酸显色法。间苯二酚显色法为套用唾液酸测定法,苦味酸显色法是对乳制品中乳糖含量检测方法的改良。两种方法的相关系数均大于0.99,线性良好。用间苯二酚法测定样品的回收试验检测结果平均值和变异系数分别为100.4%和3.09%,用苦味酸法测定样品的回收试验检测平均值和变异系数分别为99.9%和1.43%。这两种方法可以初步应用于疫苗中乳糖含量检测。  相似文献   

13.
Yan C  Hu J  Wang Y 《Amino acids》2008,35(1):65-73
Identification of outer membrane proteins (OMPs) from genome is an important task. This paper presents a k-nearest neighbor (K-NN) method for discriminating outer membrane proteins (OMPs). The method makes predictions based on a weighted Euclidean distance that is computed from residue composition. The method achieves 89.1% accuracy with 0.668 MCC (Matthews correlation coefficient) in discriminating OMPs and non-OMPs. The performance of the method is improved by including homologous information into the calculation of residue composition. The final method achieves an accuracy of 96.1%, with 0.873 MCC, 87.5% sensitivity, and 98.2% specificity. Comparisons with multiple recently published methods show that the method proposed in this study outperforms the others.  相似文献   

14.
Two major methods used by the U. S. Environmental Protection Agency (USEPA) to calculate ecological risk criteria using “species sensitivity distributions” (SSD) are compared using identical datasets. One method is the current USEPA Office of Water method for deriving acute numeric water quality criteria (EPA-FAV method). The 95% protection level generated by this method is the Final Acute Value (FAV). The other method is the USEPA Office of Pesticide Programs log normal distribution regression method that uses all available toxicological data in performing ecological risk assessments (OPP-Ecorisk method). Of the 50 comparisons made, 38% of the 95% protection levels calculated by the OPP-Ecorisk method are within a factor of 1.5 of the EPA FAV, 68% are within a factor of 2.0, 86% are within a factor of 2.5 and 92% are within a factor of 3.5. For pollutants where the difference between the OPP-Ecorisk 95% protection level and the EPA FAV are greatest, the OPP-Ecorisk 95% protection level is more protective than the EPA FAV. Where there are major differences, an analysis of the toxicity data indicates that the majority of the differences can be attributed to outliers, especially on the least sensitive ends of the toxicity distribution. In the one example dataset presented with one very sensitive genus, the OPP-Ecorisk method gave a protection level that was much closer to the lowest GMAV than the EPA-FAV method.  相似文献   

15.
《Cryobiology》2016,73(3):290-293
The purpose of this study was to investigate the potential for cryopreservation of granulocytes using 30% glycerol. Recently reported permeability data was used to design two different methods for addition and removal of glycerol: a fast method that is predicted to keep cell volumes between 80% and 150% of the isotonic volume and a slow method that is predicted to keep cell volumes between 80% and 115% of the isotonic volume. The fast method resulted in cell recoveries of 31% ± 9% and 11% ± 3% before and after freezing, respectively, whereas the slow method resulted in even lower cell recoveries of 5% ± 2% and 4% ± 2%. The reduced cell recovery for the slow method is consistent with an increase in damage as a result of glycerol toxicity. Our results suggest that cryopreservation of granulocytes in concentrated glycerol is not feasible.  相似文献   

16.
土地利用变化是影响土壤碳、氮循环的重要因素,也是研究全球气候变化的热点.本研究基于固定深度法(FD)和等效质量法(ESM),从森林开垦和退耕还林还草两个角度探讨喀斯特移民迁入区土地利用变化对土壤有机碳(SOC)和全氮(TN)储量的影响.结果表明: 原始森林被开垦为草地、桉树林和农田后,SOC和TN储量均显著减少;基于FD方法计算的SOC和TN储量分别损失了47.4%、41.6%,而通过ESM方法计算的SOC和TN的损失率分别为54.8%、49.7%.农田撂荒为草地及种植桉树后,SOC和TN储量显著增加;基于FD方法计算的SOC和TN储量提高了60.5%、49.7%,通过ESM方法计算的SOC和TN分别增加85.5%和70.8%.FD方法忽略了土地利用变化后土壤容重的差异,而森林开垦后会显著增加土壤容重,因此,FD方法高估了SOC和TN储量;农田恢复后土壤容重减小,FD方法则会低估SOC和TN储量的增加.建议相关研究选择ESM方法测算土地利用变化对SOC和TN储量的影响.  相似文献   

17.
A radioimmunoassay method based on commercially distributed antibody and antigen for measurement of bovine luteinizing hormone is presented. The method is characterized by (1) intraassay coefficient of variation (C.V.) from 1.3 to 10%, and (2) interassay C.V. from 4 to 18%. The specificity is illustrated by the cross reactivity of bFSH which is found to be 0.4%. The method provides good correlation with a previously well characterized method. Also the influence on sensitivity of length of incubation time is discussed.  相似文献   

18.
Niemann H 《Theriogenology》1985,23(2):369-379
The effects of a one-step addition of 1.4 M glycerol (method A) upon morphological appearance and developmental capacity of frozen/thawed day 7 bovine embryos were investigated and compared to a standard stepwise addition of 1.0 M glycerol (method B). With method A, the percentage of intact embryos (classified as excellent, good and poor) was 95.3% (61 out of 64) without differences between morulae (96.5%) and blastocysts (94.4%). With method B, the percentage of intact embryos was 83.0% (44 out of 53). The percentage was similar for blastocysts (89.2%) and significantly (p < 0.05) lower for morulae (68.8%) when compared to method A. The percentage of embryos with a damaged zona pellucida was considerably increased with method A (26.6%) when compared to method B (13.2%). The proportion of embryos with excluded blastomeres was similar in both methods (21.9% method A, 17.0% method B). With method A, pregnancy rates after nonsurgical transfer were 51.0% (25 out of 49) and were better than with method B (40.5%; 15 out of 37). Embryos with a damaged zona pellucida resulted in a high pregnancy rate of 66.7% (8 out of 12). A pregnancy rate of 52.9% (10 out of 17) was obtained with embryos showing some excluded blastomeres. Thus, a one-step addition of 1.4 M glycerol facilitates and accelerates the process of embryo cryopreservation and is compatible with high pregnancy rates. Damage of the zona pellucida does not impair further development of frozen/thawed bovine embryos provided blastomeres are intact.  相似文献   

19.
目的探讨真菌荧光法在皮肤浅部真菌筛查的敏感性。方法收集皮肤科门诊疑似真菌感染的患者标本,同时用KOH湿片法和真菌荧光染色法进行检测,并对检验结果进行对比。结果 1 209例患者中真菌荧光染色法阳性的阳性率为42.76%,KOH湿片法的阳性率为24.81%,结果差异有统计学意义(χ^2=87.094,P<0.05)。荧光染色法和KOH法在患者不同部位的阳性率:头面部为55.59%、7.90%,体股部为46.93%、30.06%,手足部为27.37%、26.25%,外阴部为31.85%、14.07%,指甲(趾甲)部为51.64%、48.36%;在不同疾病中的阳性率:马拉色毛囊炎为77.00%、8.50%,手足癣为48.04%、46.08%,体癣为50.31%、33.44%,甲癣为51.64%、48.36%,花斑癣为66.67%、48.00%,湿疹为10.24%、5.42%,皮炎为48.11%、9.43%。结论荧光染色法是一种简单、快速、准确的真菌镜检方法,值得在临床上推广使用。其总体的阳性率比KOH湿片法高,毛囊虫、疥疮等真菌荧光染色法在镜下更容易辨认。头面部、外阴等油脂分泌旺盛的部位以及马拉色毛囊炎、湿疹和皮炎等疾病推荐使用荧光染色法来排除是否有真菌的感染。  相似文献   

20.
通过比较不同的提取方法对牛耳草新鲜和脱水叶片中代谢物的提取效率,旨在建立一种可以有效鉴定并分析牛耳草脱水过程中关键小分子代谢物的种类和含量变化的方法,为研究植物耐脱水分子机制提供技术方法。本研究以气相色谱-质谱联用(GC-MS)为分析方法,对复苏植物牛耳草代谢物提取方法进行比较。从提取总色谱峰数目、提取效率、代谢物保留时间和提取效率稳定性等方面比较甲醇溶液(A法)和甲醇-氯仿-水溶液(B法)两种提取方法的提取效果。对牛耳草新鲜样品提取结果表明,B法提取的总色谱峰数目多于A法;对9种共有代谢物的提取效率比较结果表明,B法的提取效率高于A法;对10种色谱峰的保留时间和提取效率的方法学考察结果表明,两者保留时间RSD(相对标准偏差)值均小于1%,A法提取效率的RSD值≤10%的比例为50%,B法的为100%。A法对干样的提取色谱峰数目远少于鲜样,而B法对干样的提取色谱峰数目和鲜样没有显著差异,保留时间RSD值均小于1%,提取效率的RSD值与鲜样没有差异,稳定性良好。  相似文献   

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