示波极谱法测定血清和组织中的亚硝酸盐

用示波极谱法测定血清和组织匀浆中的亚硝酸盐。取０．１０ｍｌ血清或组织匀浆,样液中的ＮＯ－２在稀盐酸介质中,与磺胺和盐酸萘乙二胺反应生成偶氮化合物,在氨碱性介质中,该偶氮化合物可产生灵敏的极谱波,波高与ＮＯ－２含量在一定范围内成正比关系。本法检出限为０．５６μｇ／Ｌ（相应血清浓度和组织含量分别为０．６１μｍｏｌ／Ｌ和０．２２μｇ／ｇ）,相对标准差为６．１％～７．８％。加标回收率为９２．０％～１０８．０％（平均１００．６％）。本法具有灵敏度高,操作简便和样品不需除蛋白即可直接测定等优点。     

血清中亚硝酸盐的化学发光测定法

基于盐酸介质中Ⅰ与ＮＯ２＾－反应产生的Ⅰ２氧化鲁米诺（Ｌｕｍｉｎｏｌ）而产生的化学发光反应，建立了Ｌｕｍｉｎｏｌ－Ⅰ－ＮＯ２＾－偶合化学发光体系测定血清中亚硝酸根（ＮＯ２＾－）的方法。测定ＮＯ２＾－的线性范围为（０．０１８￣３００）μｇ／Ｌ，检出限为０．０２６μｇ／Ｌ，用于血清中ＮＯ２＾－的测定，结果满意。     

血清中亚硝酸盐的化学发光测定法

基于盐酸介质中Ｉ－与ＮＯ－２反应产生的Ｉ２氧化鲁米诺（Ｌｕｍｉｎｏｌ）而产生的化学发光反应，建立了Ｌｕｍｉｎｏｌ－Ｉ－ＮＯ－２偶合化学发光体系测定血清中亚硝酸根（ＮＯ－２）的方法。测定ＮＯ－２的线性范围为（０．０１８～３００）μｇ／Ｌ，检出限为０．０２６μｇ／Ｌ，用于血清中ＮＯ－２的测定，结果满意     

用镉还原NO3^—法测定小鼠血清及肝组织一氧化氮的含量

采用镉还原法测定了小鼠血清及肝组织内一氧化氮（ＮＯ）的含量,并观察了ｉｐ细菌内毒素（ＬＰＳ）后小鼠血清ＮＯ含量变化。通过检测ＮＯ在体内稳定的代谢产物ＮＯ２－／ＮＯ３－来表示ＮＯ的含量。用本法测定的正常昆明、ＩＣＲ、ＢＡＬＢ／ｃ小鼠血清及肝组织内ＮＯ２－／ＮＯ３－含量分别为３８．７±７．９,４８．８±４．４,４４．２±５．９μｍｏｌ／Ｌ及６４．４±２．２,７９．５±１２．１,７３．３±２９．３ｎｍｏｌ／ｇ;应用本法测定的正常ＩＣＲ小鼠血清及肝组织内ＮＯ２－／ＮＯ３－含量与应用硝酸根还原酶试剂合法测得值基本吻合;ｉｐ１,２,３ｍｇ／ｋｇ细菌内毒素后,ＩＣＲ小鼠血清的ＮＯ２－／ＮＯ３－含量分别上升至１６２．５±４７．８,４９４±１２３．６,６７４．８±２５９．７μｍｏｌ／Ｌ。表明本法测定这些生物样品中ＮＯ的含量是简便、可靠、有效的     

一氧化氮检测在新生儿败血症中的应用

为探讨一氧化氮（ＮＯ）在新生儿败血症中的作用，测定了２０例新生儿败血症外周血亚硝酸／硝酸根离子（ＮＯ２＾－／ＮＯ３＾－）水平。结果表明：新生儿败血症外周血ＮＯ２＾－／ＮＯ３＾－水平与肿瘤坏死因子水平密切相关（Ｐ＜０．０５）。８例外周血ＮＯ２＾－／ＮＯ３＾－水平高于２００μｍｏｌ／Ｌ者，６例发生休克；其余１２例ＮＯ２＾－／ＮＯ３＾－水平低于此标准者，无一例发生休克，差别显著（Ｐ＜０．０５）。本文显示     

体内一氧化氮测定的技术及临床应用

采用硝酸还原酶和甲酸脱氢酶偶联反应，建立了测定血清ＮＯ３－／ＮＯ２－含量的新方法，对酶浓度、还原时间、ｐＨ、ＮＡＤＨ浓度进行了条件测试。本法重复性好，回收率高，操作简便，线性范围可达ＮＯ３－浓度２００μｍｏｌ／Ｌ。３２例正常人血清ＮＯ３－／ＮＯ２－浓度为８２．９±１７．７μｍｏｌ／Ｌ。一例小肠移植术后患者分别于术后３、５、７、１４、３０、４５、６０和９０ｄ测得血清ＮＯ３－／ＮＯ２－浓度为５８．５～９１．４μｍｏｌ／Ｌ，属正常范围，表明无排异现象发生。２０例慢性腹腔感染患者血清ＮＯ３－／ＮＯ２－浓度为４６．０±１７．５μｍｏｌ／Ｌ，显著低于正常人（Ｐ＜０．０１），并与感染患者严重程度呈显著负相关。因此，感染患者ＮＯ检测可作为其感染严重程度的指标     

血清亚硝酸盐的快速测定

目的：建立一种无需去蛋白的血清亚硝酸盐的快速测定方法。方法：加入蛋白活化剂后，直接用Ｇｒｉｅｓ试剂显色分光光度测定。结果：方法的检测下限为０．２μｍｏｌ／Ｌ，相对标准差为５．１３％～８．８６％，回收率为９４．５％～９９．８％（平均为９７．８％）。血清ＮＯ－２浓度为１４．３８±０．２５μｍｏｌ／Ｌ时，批内变异系数为１．７５％，ＮＯ－２浓度为５．６９±０．２５μｍｏｌ／Ｌ时，批间变异系数为４．４６％。测定５５例正常人血清，得到血清中ＮＯ－２浓度的平均值分别为５．３６±２．１６ｕｍｏｌ／Ｌ；对糖尿病病人血清测定结果表明，亚硝酸盐浓度明显高于正常人。与去蛋白的Ｇｒｉｅｓ试剂分光光度法比较，结果无统计学差异。结论：用蛋白活化剂替代蛋白沉淀剂，减少操作步骤和干扰，测定准确、简便、快速，适用于血清中ＮＯ－２的测定。     

肿瘤患者血清中NO与Ca^2＋的关系及其临床意义

研究了肿瘤患者血清ＮＯ，Ｃａ＾２＋的含量和两者之间的关系，以及Ｍｇ＾２＋，γ－谷氨转肽酶（γ－ＧＴ），前白蛋白（ＰＡＢ），白蛋白（ＡＬＢ）等的变化规律，结果表明，ＮＯ和Ｃａ＾２＋含量增加（ｒ＝０．８６１２）γ－ＧＴ活性升高，Ｍｇ＾２＋ＰＡＢ及ＡＬＢ含量降低，Ｃａ＾２＋可促进ＮＯ生成，ＮＯ与肿瘤发生，发展有关，提示测定肿瘤患者ＮＯ含量对肿瘤诊断，治疗和预后判断有重要意义。     

慢性阻塞性肺病患者血中亚硝酸盐／硝酸盐含量的变化及其意义

目的：探讨血清中一氧化氮（ＮＯ）代谢终产物－－亚硝酸盐／硝酸盐（ＮＯ２＾－／ＮＯ３＾－）测定在慢性阻塞性肺病（ＣＯＰＤ）的应用价值。方法：和镉还原显色法测定５９例ＣＯＰＤ患者治疗前后血中ＮＯ２＾－／ＮＯ３＾－含量。结果：ＣＯＰＤ患者急性发作期患者血清ＮＯ２＾－／ＮＯ３＾－高于正常对照组（Ｐ〈０．０１）,缓解期患者血清中ＮＯ２＾－／ＮＯ３＾－测定明显高于正常对照组（Ｐ〈０．０１）。结论：血清ＮＯ２＾     

健脾益气方对大鼠乙酸慢性胃溃疡的影响及其机制探讨

运用大鼠乙酸慢怀胃溃疡模型采用中药健脾益气方，观察治疗７ｄ及２１ｄ后溃疡指数，溃疡抑制率及血清脂质过氧化物（ＬＰＯ）和ＮＯ＾－３／ＮＯ＾－２含量变化，结果显示，中药治疗组溃疡指数，血清ＬＰＯ含量显著低于模型组（Ｐ〈０．０１），溃疡抑制率及血清ＮＯ＾－３／ＮＯ＾－２含量显著高于模型组（Ｐ〈０．０１），与雷尼替丁组相比较溃疡指数，血清ＬＰＯ含量无统计学差异，但溃疡抑制率及血清ＮＯ＾－３／ＮＯ＾－２含量     

示波极谱法测定罐头食品中的锡

目的：建立测定罐头食品中锡的示波极谱测定法。方法：利用锡在硫酸(H2SO4)-碘化钾(KI)-抗坏血酸(Vit C)-偏钒酸铵(NH4VO3)体系中有一灵敏的极谱波，对几种罐头食品中的锡进行测定。结果：锡浓度在O～2．Oμg／ml时线性良好，方法：检出限为O．12μg／L，相对标准偏差(RSD)在4．22％～8．33％之间；样品平均回收率为94．7％～112．O％。将本法与食品国家卫生标准方法比较，结果令人满意。结论：本法简便、快速、灵敏，测定干扰少，可用于实际样品的测定。     

催化极谱法测定关系水中钛

Titanium has a very sensitive catalytic polarographic wave in the system of cupferon-hexamine-sodium sulfate at pH 6.0-6.4. The catalytic current was proportional to the content of titanium. High blank of the reagents could be improved by extraction with the system of cupferron-chloroform. For determination, samples were filtered with quantitative filter paper, but it was not necessary for drinking water samples. The filtration was acidified with HCl to 0.5% (V/V) and heated in a boiling water bath for 30 min, 5 ml sample was sufficed to most analyses. The detection limit was 0.12 microgram/L. The coefficient of variation was 8% for 6 determinations at 0.2 microgram/L. Three levels of titanium were spiked to one sample, and it was found that the recoveries were 96-101%. The proposed method was applied to rain water, well-head water, well water, tap water and river water. The content of titanium of most samples was less than 2 micrograms/L.     

二阶导数示波极谱检测人血清中NO2-含量方法的建立

目的 NO2-是NO在体内的代谢产物之一,直接测定NO2-含量更能反映血清中NO含量的真实情况.本实验则建立一种直接测定人血清中NO2-含量的方法——阶导数示波极谱法.方法 采用对氨基苯磺酸和8-羟基喹啉为测定体系,使用二阶导数示波极谱测定血清中的NO2-含量.结果 该方法的检出限为9.6×10^-3 μg·ml^-1,线性范围为0.05～66.7 μg·ml^-1,精密度为4.91％,平均回收率为102.6％.结论 二阶导数示波极谱法测定人血清中NO2-含量是一种灵敏、准确、重复性好、试剂安全的方法.     

CCD—二级管陈列检测分光光度法同时测定镉和铅研究

为了同时测定有害元素铅（Ｐｂ）和镉（Ｃｄ），建立了以电荷耦合器件（ＣＣＤ）作为陈列光信号探测器，小型多色仪和专用微机组成的分光光度装置，研究了Ｍｅｓｏ－四（４－三甲铵基苯基）卟淋与Ｐｂ和Ｃｄ显色反应的最佳条件。测定了合成试样、陶瓷及搪瓷食品容器泡液中Ｐｂ＾２＋、Ｃｄ＾２＋的含量，加标加收率为８４．４％￣１１８．６％，平均回收率为１００．８％，相对标准偏差小于９．１％。本法较常规分光光度法更为灵敏、     

Antimicrobial effect of acidified nitrate and nitrite on six common oral pathogens in vitro

Background Salivary nitrate is positively correlated with plasma nitrate and its level is 9 times the plasma level after nitrate loading. Nitrate in saliva is known to be reduced to nitrite by oral bacteria. Nitrate and nitrite levels in saliva are 3-5 times those in serum in physiological conditions respectively in our previous study. The biological functions of high salivary nitrate and nitrite are still not well understood. The aim of this in vitro study was to investigate the antimicrobial effects of nitrate and nitrite on main oral pathogens under acidic conditions. Methods Six common oral pathogens including Streptococcus mutans NCTC 10449, Lactobacillus acidophilus ATCC 4646, Porphyromonas gingivalis ATCC 33277, Capnocytophaga gingivalis ATCC 33624, Fusobacterium nucleatum ATCC 10953, and Candida albicans ATCC 10231 were cultured in liquid medium. Sodium nitrate or sodium nitrite was added to the medium to final concentrations of 0, 0.5, 1, 2, and 10 mmol/L. All of the microorganisms were incubated for 24 to 48 hours. The optical densities （OD） of cell suspensions were determined and the cultures were transferred to solid nutrient broth medium to observe the minimum inhibitory concentration and minimum bactericidal/fungicidal concentration for the six tested pathogens. Results Nitrite at concentrations of 0.5 to 10 mmol/L had an inhibitory effect on all tested organisms at low pH values. The antimicrobial effect of nitrite increased with the acidity of the medium. Streptococcus mutans NCTC 10449 was highly sensitive to nitrite at low pH values. Lactobacillus acidophilus ATCC 4646 and Candida albicans ATCC 10231 were relatively resistant to acidified nitrite. Nitrate at the given concentrations and under acidic conditions had no inhibitory effect on the growth of any of the tested pathogens. Conclusion Nitrite, at a concentration equal to that in human saliva, is both cytocidal and cytostatic to six principal oral pathogens in vitro, whereas nitrate at a similar concentration has no antimicrobial effect on these organisms.     

全氟丙烷人血白蛋白微球注射剂中全氟丙烷气体含量测定

目的建立一种新型的测定全氟丙烷人血白蛋白微球注射剂中全氟丙烷气体含量的方法。方法采用气相色谱-质谱选择离子方式(GC-MS/SIM)。结果该方法在全氟丙烷浓度为40.92-16368nmol/L范围内,线性关系良好,标准曲线方程为Y=51.13X 40.38,R2=0.9999;其方法检测限为8.18nmol/L。在低(204nmol/L)、中(2046nmol/L)、高(8184nmol/L)3个浓度下回收率分别为(100.98±1.4)%、(102.63±2.29)%和(97.5±2.2)%;日内精密度RSD%分别为0.6%、1.67%和2.0%;日间精密度RSD%分别为0.86%、1.75%和2.3%。结论该方法简便、快速、灵敏、准确、精密度高,可作为质控的有效手段。     

毛细管电泳法测定玉米赤霉烯酮及其代谢物

目的 建立粮食样品中玉米赤霉烯酮及其代谢物的毛细管电泳测定方法。方法 样品经液－液超声波提取，C18小柱净化后，胶束电动毛细管电泳（MEKC）测定。结果 玉米赤霉烯酮（Zeralenone,ZON),α-Zearalenon (α-ZOL)，β-Zearalenol(β-ZOL），黄曲霉B1（Aflatoxin B1,FT B1)，赭曲霉A（Ochratoxin A,Och A)的检出限分别为：0.0084,0.081,0.14,0.0016,0.031μml。样品加标回收率77．9％－103．1％，相对标准偏差0．63％－1．98％。结论 该法灵敏，准确，可用于粮食样品中玉米赤霉烯酮等真菌毒素的测定。     

尿铬测定方法研究

Systemic investigations of chromium determination in urine with diphenylcarbazide were carried out and suitable analytic conditions for the determination established. Urine samples were first digested with nitric acid-hydrogen peroxide and then the chromium in the sample was oxidized to the hexavalent state by permanganate in acidic medium. After the excess oxidizing reagent was destroyed with sodium nitrite, chromium (VI) combined with diphenylcarbazide, forming a stable red color. The average recovery was 101.1%, ranging from 82.0% to 115.8%. Coefficients of variation were in the range from 2.0% to 8.4%. The method can be conveniently applied to the analysis of trace chromium in urine samples with satisfactory sensitivity and recovery. The method was applied to the measurement of 180 normal and 124 CHD (coronary heart disease) urine samples from Chengdu city. The mean of chromium level in normal urine was 6.1 micrograms/L and the range with 95% confidence of urine chromium was determined as 1.7-11 micrograms/L. The mean of chromium level in CHD urine samples was 4.2 micrograms/L. By statistical analysis, there was a significant difference between the means of the two groups (t' = 6.9, P less than 0.05).     

Effects of cyclosporine A on insulin content and insulin release in neonatal rat islet cell monolayer cultures]

We investigated the effects of cyclosporine A (CsA) on insulin content and insulin release in neonatal rat islet cell monolayer cultures. Insulin content in 5.5-day-old monolayers was not affected after 12-hour incubation in the medium containing 16.7 mmol/L glucose plus 0.1 or 100 micrograms/ml CsA and 5.6 mmol/L glucose plus 10 micrograms/ml CsA. Insulin release in 7.5-day-old monolayers was inhibited after 12-hour incubation in the medium containing 5.6 or 16.7 mmol/L glucose plus 0.01-100 micrograms/ml CsA in a dose-responsive manner. At 16.7 mmol/L glucose, CsA less than or equal to 0.1 microgram/ml did not affect insulin release, while CsA greater than or equal to 1.0 microgram/ml significantly inhibited insulin release and the inhibitory effect did not return to normal after a 16-hour incubation in CsA-free medium. At 5.6 mmol/L glucose, CsA 1.0 microgram/ml did not affect insulin release. CsA 100 micrograms/ml inhibited insulin release less than it did at 16.7 mmol/L glucose. These experimental data demonstrated that high doses of CsA have inhibitory effects on insulin release in islet monolayer cultures.