气相色谱外标法测定饲料添加剂丙二醇(包膜型)含量

为建立气相色谱外标法测定饲料添加剂丙二醇(包膜型)的含量,本研究采用中国科学院兰州化学物理研究所色谱中心PEG-20M毛细管色谱柱(30 m×0.25 mm×0.25μm);柱温150℃,保持6 min;进样口温度270℃;检测器温度280℃;检测器为火焰离子化检测仪(Flame Ionization Detector,FID);载气为氮气(N2);色谱柱流量1.5 mL/min;进样模式为分流进样;进样1μL,分流比为20:1进行测定。结果显示丙二醇在1 mg/mL～5 mg/mL的检测浓度范围内呈良好线性关系(r2=0.999 6),最低定量限为3.2μg。该方法操作简便、灵敏、准确,适用于饲料添加剂产品中丙二醇的含量控制。     

气相顶空法检测c-met抑制剂中异戊醇的残留

目的:用气相顶空外标法检测药物中的异戊醇残留。方法:将样品溶于N,N-二甲基咪唑啉酮,顶空90℃保持30 min,采用毛细管气相色谱柱HP-INNOWax(30 m×250μm×0.25μm);FID检测器;载气为氮气;流速3 mL/min;检测器温度250℃;进样口温度200℃;分流比5/1;程序升温:起始温度40℃,保持3 min,再以5℃/min温至90℃,保持5 min,最后以20℃/min升温至230℃,保持5 min。结果:异戊醇的线性范围为1.05~67.04μg/mL(R~2=0.998 2),定量限:1.05μg/mL,回收率为95.79%~98.78%,精密度1.0%,溶液稳定性符合设计要求。结论:所建立的气相顶空法灵敏准确、精密稳定,适合对药品中异戊醇的检测研究。     

甲基丙烯酸甲酯在真丝上接枝共聚反应条件的优化

对有引发剂和无引发剂存在时甲基丙烯酸甲酯对真丝接枝增重的工艺条件进行研究,并用正交试验法探讨了不同的温度、时间、单体质量浓度等对接枝增重效果的影响。有引发剂的接枝聚合反应最佳工艺条件为反应温度80℃、单体质量浓度50g/L、反应时间40min;反应温度和单体质量浓度对接枝率的影响极其显著,反应时间对接枝率的影响不显著。无引发剂的接枝聚合反应最佳工艺条件为反应温度80℃、单体质量浓度55g/L、反应时间3h,反应温度对接枝率的影响极其显著,反应浓度对接枝率的影响比较显著,反应时间对接枝率的影响不显著。     

离子色谱法测定油田增强剂中Cl-的含量

本文采用离子色谱仪,建立了一种快捷测定油田外加剂增强剂中氯离子含量的方法。以20mM KOH溶液为淋洗液,AS19分离柱(250mm×4mm)分离,电导检测器检测,柱温、检测器温度为30℃,进样量为10μL,流速为1.0mL/min,峰面积定量。氯离子的检出限为0.01mg/L,在2~25mg/L范围内具有良好的线性关系(r2=0.9998),加标回收率均在98%以上,相对标准偏差(RSD)为1.2%~1.4%。经实验表明,此方法简单、快速,可便捷地应用于油田外加剂增强剂中氯离子含量的测定。     

气相色谱法测定喉炎净散中龙脑的含量

建立气相色谱法测定喉炎净散中龙脑含量的方法。色谱柱：DB-WAX 30 m×0.25 mm×0.25μm,柱温：140℃,进样口温度：160℃,检测器温度：180℃,柱流量：1 mL/min,以氮气为载气,以乙酸乙酯为溶剂,以水杨酸甲酯为内标。龙脑进样量在0.1999~3.998μg时峰面积比与浓度呈良好的线性关系（R2=0.999）,平均回收率为99.1%,RSD为0.7%。该方法快速、灵敏、准确,可作为喉炎净散质量评价的依据。     

HPLC法测定氨苄西林钠可溶性粉中氨苄西林的含量

采用HPLC法测定氨苄西林钠可溶性粉中氨苄西林的含量.色谱柱为WaterssphericalC18(3.9mm×150mm,5μm),流动相为水-乙腈-1mol/L磷酸二氢钾溶液-1mol/L醋酸溶液(909∶80∶10∶1,V/V),检测波长254nm,流速1.0mL/min,柱温30℃,保留时间约4.5min.氨苄西林在0.25～2.0mg/mL范围内具有良好的线性关系(r=0.9999),平均回收率99.6%,RSD为0.3%.     

离子色谱法测定盐酸头孢噻呋中的氯离子

建立了离子色谱法测定盐酸头孢噻呋中氯离子含量的方法。试验采用Dionex Ion Pac AS19(250 mm×4 mm,5μm)阴离子交换色谱柱,以氢氧化钾溶液为淋洗液,流速为1.0 m L/min,柱温为30℃,检测池温度为35℃,抑制型电导检测器。试验结果表明氯离子与常见成盐阴离子分离良好,在0.5~20μg/m L浓度范围内呈良好的线性关系(r2=0.9999),加样回收率为101.4%(n=9,RSD=1.7%)。建立的方法准确、灵敏、专属性好,可用于测定盐酸头孢噻呋中氯离子的含量,以控制成盐比例。     

离子色谱法测定磷酸替米考星中磷酸根含量

建立离子色谱法测定磷酸替米考星中的磷酸根含量,并考察替米考星与磷酸的成盐比率。方法:色谱柱为ASLL-HC阴离子交换柱(250 mm×4 mm),检测器为电导检测器,流动相为30 mmol/L氢氧化钠溶液,流速为1.0 m L/min,柱温为30℃,进样体积为25μL。结果:磷酸根离子的检测限与定量限分别为0.002μg/m L、0.006μg/m L,在0.1~4.0μg/m L范围内线性关系良好(R2=0.9991),精密度良好(RSD=1.04%,n=8),平均回收率为99.11%(RSD=0.33%,n=9)。磷酸替米考星中替米考星与磷酸的成盐率约为1∶1。结论:所建立的离子色谱法专属性强、精密度好、准确度高,可用于磷酸替米考星的磷酸根含量与成盐率测定,5批磷酸替米考星样品的成盐状态良好。     

偶氮二异丁脒盐酸盐引发甲基丙烯酰胺接枝真丝纤维的反应性及工艺条件研究

对真丝织物接枝增重是改善其抗皱性和耐水洗性能的方法之一。采用偶氮二异丁脒盐酸盐(AIBA)为引发剂,将单体甲基丙烯酰胺(MAA)接枝到真丝纤维上,研究接枝的反应性及工艺因素对真丝织物接枝增重率的影响。通过单因素试验获得引发剂AIBA引发单体MAA接枝真丝纤维的最佳工艺条件是:MAA浓度0.31 mol/L,AIBA浓度2.95 mmol/L,浴比1∶30,反应液pH 9,反应温度80℃,反应时间60 min。当单体MAA和引发剂AIBA的浓度分别为0.31 mol/L、2.95 mmol/L时,真丝纤维的活性基团与单体、引发剂之间的反应性(表观反应速率)Rg=K[MAA]1.58[AIBA]0.21,由此得出单体MAA在水相中接枝真丝纤维的表观活化能为148.46 kJ/mol。     

HPLC-DAD法同时测定清乳通贴膜剂中绿原酸和黄芩苷的含量

目的:建立清乳通贴膜剂中绿原酸和黄芩苷含量测定的方法。方法:采用反相高效液相色谱法,色谱柱:Agilent ZORBOX SB-C18色谱柱(5μm,4.6 mm×250 mm),流动相:乙腈(A)-0.2%磷酸水溶液(B),线性梯度洗脱[0-30min,A-B(20∶80)→A-B(60∶40)],流速:1.00 m L/min,柱温:40.0℃。检测器:二极管阵列检测器,检测波长:绿原酸327.0 nm、黄芩苷280.0 nm。结果:绿原酸和黄芩苷线性范围分别为0.14-1.39μg(r=0.999 6)、0.29-2.87μg(r=0.999 9);平均加样回收率(n=6)分别为98.71%(RSD=0.39%)、99.95%(RSD=0.49%)。结论:本方法简捷快速,结果准确可靠,适用于清乳通贴膜剂的质量控制。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.