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31.
The earliest sign of osteoarthritis is acute synovitis with joint effusion and elevated intraarticular pressure, which causes compression of the intracapsular vein segments draining the epiphyseal bone compartment. The increased outflow resistance may cause a fall in the regional blood flow and thereby lead to a state of tissue hypoxia. The acute osteoarthritis may also affect the transfer of oxygen to the cartilage across synovial membrane because of the extensive inflammation with hypercellularity and edema.In the present study we have investigated the subchondral P02 and Pc02 in acute osteoarthritis. There was no significant difference between these gas tensions in the normal and osteoarthritic bone. We have also investigated the oxygen consumption and diffusion capacity in the synovial membrane. The latter was decreased by a factor of 4 in the osteoarthritic joints whilst the oxygen consumption was increased by a factor of 3. 相似文献
32.
QuEChERS-超高效液相色谱-质谱联用法测定熊胆粉中9种苯二氮䓬类药物残留量 总被引:1,自引:0,他引:1
建立了超高效液相色谱-质谱联用法(UPLC-MS/MS)快速测定中药材熊胆粉中9种苯二氮?类药物残留的方法。样品以乙腈为提取溶剂,经萃取盐包除杂提取,采用分散式固相萃取管 (EMR-Lipid dSPE) 净化,ACQUITY BEH C18色谱柱(1.7 μm,2.1×100 mm)分离,多反应监测模式(MRM)采集数据,外标法定量。在优化的条件下,虽9种药物存在不同程度的基质效应,但不影响检测结果的准确性。方法学考察结果显示,9种苯二氮?类药物在对应的浓度范围内线性关系良好,决定系数(R2)≥0.9961,方法检出限(LOD,S/N =3)在0.06~0.71 μg/kg范围内,定量限(LOQ,S/N =10)在0.20~2.60 μg/kg范围内,3个加标水平的平均回收率在69.1%~108.0%范围内,日内RSD为1.8%~9.0%,日间RSD为2.6%~9.3%。该方法前处理操作简便、重现性好,准确度高,为熊胆粉中苯二氮?类药物残留的风险监控提供了一种有效的检测技术。 相似文献
33.
Fumihito Takahashi Mariko Mochizuki Touko Sato Kinya Katayama Paul R. Kenyon Stephen T. Morris Peter D. Kemp Takeyuki Ozawa Fukiko Ueda Hiroyuki Tazaki 《Animal Science Journal》2013,84(6):496-501
The establishment of a classification system for domestic animals on consumed feed stuff is thought to be important from both a hygiene and market point of view. We collected plasma samples of Romney lambs (Ovis aries) which were fed one of the following: a herb‐clover mix (n = 10) which included chicory, red clover, white clover and plantain; a plant‐grass mix (n = 10) which included plantain, ryegrass and white clover; or a grass mix (n = 10) which included ryegrass and white clover. A total of 20 elements in plasma samples obtained from the lambs were analyzed using inductively coupled plasma mass spectrometry. The data were then analyzed by principal component analysis. The lambs were divided into three groups on a score plot depending on the different feed conditions. Furthermore, discriminant analyses of the elements were examined, using linear discriminant analysis with forward stepwise regression. This discriminant function correctly classified the samples from each group. The accuracy of classification of each group, as shown by 10‐fold cross‐validation, proved the effectiveness of the established discriminant function. It is concluded that using linear discriminant analysis might be a useful tool for the validation of elements from plasma in lambs grown in different conditions. 相似文献
34.
建立了乳与乳制品中20种邻苯二甲酸酯气相色谱-质谱联用仪分析方法.样品用正己烷提取后,采用DB-5MS(30m×0.25mm,0.25μm)石英毛细管柱分离,在进样口温度280℃,传输线温度280℃,离子源温度230℃条件下20种邻苯二甲酸酯完全分离.该方法各组分的相关系数均大于0.9990,线性范围0~10μg/mL,样品加标回收率为80%~109%.邻苯二甲酸二异壬酯、邻苯二甲酸二异癸酯化合物检出限分别为1.0、0.5mg/kg,其他化合物均为0.05mg/kg.该方法具有简单易行,快速准确,灵敏度高等优点. 相似文献
35.
以GB/T 20752-2006中的实验方法为基础,对超高效液相色谱-串联质谱法(UPLCMS/MS)检测水产品中呋喃它酮(AMOZ)、呋喃西林(SEM)、呋喃妥因(AHD)和呋喃唑酮(AOZ)4种硝基呋喃代谢物的样品前处理方法进行了改进。试样用0. 2 mol/L盐酸溶液溶解后,经2-硝基苯甲醛衍生化,加入0. 1 mol/L磷酸氢二钾,混匀后用1 mol/L氢氧化钠溶液调节pH约为7. 4。经乙酸乙酯直接振荡离心提取上清液,氮气吹干经超高效液相色谱串联质谱,采用正离子多反应监测(MRM)模式检测,同位素内标法定量。结果表明,四种代谢物回收率控制在90%~120%之间,RSD10%。实际样品分析结果显示,新的样品前处理方法简单、分析时间短、结果可靠,适合水产品中硝基呋喃代谢物残留的测定。 相似文献
36.
为完善止痢散质量标准,采用氢化物发生-原子荧光光谱法对止痢散中三氧化二砷的含量测定进行了研究。载流为3.0%盐酸溶液,还原剂为含0.5%氢氧化钾的1%硼氢化钾溶液,氩气载气流量为600mL/mL,砷空心阴极灯电流为60mA。砷元素进样浓度在0~100ng/mL范围内与荧光强度值呈良好的线性关系(r=0.9999);样品平均回收率为95.3%(n=6),RSD为1.9%。本方法简便、准确度高、重复性好,为进一步控制止痢散的质量提供了依据。 相似文献
37.
对农业执法案件中缴获的未知粉末进行分析研究。应用超高效液相色谱-飞行时间高分辨质谱(UPLC-TOF-HRMS)获得未知物分子离子峰的精确质量数、天然同位素信息,二级特征碎片的精确质荷比,并应用SCIEX PeakView及MasterView软件进行分析。经过靶向及非靶向筛查,同时参考文献报道,推导出未知粉末中的疑似化合物。采用高效液相色谱-二极管阵列检测器(HPLC-PDA)法及UPLC-TOF-HRMS法进行了双重确证。结果显示该未知粉末中含克仑特罗(16 g?kg-1)及其合成前体克仑特罗杂质B(455 g?kg-1)。本文详述的分析技术可为未知添加物的筛查和确证提供思路和技术参考。 相似文献
38.
39.
Noboru SASAKI Thandar OO Yoshikazu YASUDA Takahiro ICHISE Noriyuki NAGATA Nozomu YOKOYAMA Kazuyoshi SASAOKA Keitaro MORISHITA Shouta MM NAKAYAMA Mayumi ISHIZUKA Kensuke NAKAMURA Mitsuyoshi TAKIGUCHI Yoshinori IKENAKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1634
We developed an analytical method using an on-line column-switching liquid chromatography with triple quadrupole mass spectrometry (LC/MS/MS) for quantifying multiple steroids in serum. Using the developed method, we evaluated the serum concentration of nine steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 21-deoxycortisol, deoxycorticosterone, progesterone, 17α-OH-progesterone and aldosterone) in dogs with hyperadrenocorticism (HAC). Serum was mixed with stable isotope internal standards and thereafter purified by the automated column-switching system. The limit of detection ranged 2–16 pg/ml for nine steroids. In the baseline samples, five steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, and 17α-OH-progesterone) were detected in all dogs. The concentrations of cortisone, 11-deoxycortisol, and 17α-OH-progesterone in dogs with HAC (n=19) were significantly higher those in dogs without HAC (n=15, P<0.02). After the adrenocorticotropic hormone stimulation test, six steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 17α-OH-progesterone, and deoxycorticosterone) were above the limit of quantification in all dogs. Cortisol, corticosterone, cortisone, and deoxycorticosterone concentrations of dogs with HAC were significantly higher than those of dogs without HAC (P<0.02). In addition, 11-deoxycortisol and 17α-OH-progesterone concentration was higher in dogs with HAC than in dogs without HAC (P=0.044 and P=0.048, respectively). The on-line column-switching LC/MS/MS would be feasible for measuring multiple steroids in dog serum. The results suggest that cortisone, 11-deoxycortisol, and 17α-OH-progesterone would be related to HAC. Further studies are warranted to assess the clinical feasibility of steroid profile in dogs with HAC. 相似文献
40.
石墨炉原子吸收光谱法测定新资源食品中的硒含量 总被引:1,自引:0,他引:1
建立一种简便、快速、准确的食品中硒的测定方法;检测新资源食品芝麻叶、野生四叶参、野生菜葛根、野生葛花及桑蚕蛹中的硒含量。用1mg·mL-1硝酸镍为基体改进剂,加入体积分数为0.1%TritonX-100和0.5%硝酸(1∶1),以改善样液的表面张力。用HITACHIZ-5000型石墨炉原子吸收光谱仪及全自动进样方法进行硒含量测定。石墨炉采用光控升温方式,硒的灰化温度按程序升温方式进行,程序升温分为干燥、灰化、原子化和净化。该方法的测定限为18.6μg/L,精密度为3.26% ̄9.29%(RSD),加标回收率为92.1% ̄108.8%。该方法具有测定简便、快速和准确等特点,可作为食品中硒含量测定的良好方法。 相似文献