2—氯—4—硝基苯—β—D—半乳糖—麦芽二糖苷作底物测定淀粉酶总活性

目的 建立2－氯－4－硝基苯－β-D－半乳糖－麦芽二糖苷（GalG2-CNP）作底物测定淀粉酶的方法。方法 用连续监测法对pH值，Km值及最适底物浓度等反应条件进行实验研究，并对建立的方法进行评价。结果 用双试剂连续监测法；试剂Ⅰ：含KSCN 200mmol/L,CaCl26.7mmol/L,NaCl400mmol/L；试剂Ⅱ：含GalG2-CNP20mmol/L；均用pH6.0 50mmol/L MES缓冲液。线性范围达1200U/L批内CV＝2.77％，批间CV＝3.56％，与参考方法（BPS－G7）有良好的相关性。结论 本法操作简便，结果准确，可用于常规分析。     

连续监测法测定腺苷脱氨酶

目的 建立连续监测法测定腺苷脱氨酶的方法。方法 用连续监测法对 pH值、腺苷浓度等反应条件进行实验研究，并对所建立的方法进行评价。结果 用双试剂连续监测法；试剂Ⅰ：含α－酮戊二酸6mmol/L,NADH 0.35mmol/L,ADP0.8mmol/L,EDTA-Na2 0.1mmol/L，谷氨酸脱氢酶1000U／L，试剂Ⅱ：腺苷12mmol/L,均用磷酸盐缓冲液（0．1mol/L);pH7.2。线性范围达97U／L，批内CV＝4．90％，批间CV＝6．53％。与波氏显色法有良好的相关性（r=0.9902)。结论 本法操作简便，结果准确，可用于常规分析。     

尿素酰基裂解酶酶偶联法测定血清总钙

目的 介绍尿素酰基裂解酶酶偶联测定血清总钙的方法。方法 双试剂两点法；缓冲液为三乙醇胺（TEA，pH8.0,200mmol/L）；试剂I：含NaHCO326.0mmol/L,NADPH 0.4mmol/L,α－酮戊二酸8.0mmol/L，尿素酰基裂解酶115U／L，GLDH43．0kU/L；试剂Ⅱ：含NaCO3 26.0mmol/L,ATP6.2mmol/L。结果 方法线性范围为0．5－5．0mmol/L，批内和批间平均变异系数分别为2．13％和2．69％。平均回收率为102．7％ 。本法（Y）与邻甲酚酞络合酮法（OCPC法，X1）比较：r＝0．981，Y1＝1．02X1－0．021，与偶氮胂Ⅲ法（X2）比较：r＝0．978，Y＝0．99X2＋0．03。血清胆红素高达300μmol/L，血红蛋白4g/L，镁2.5mmol/L，NH4^ 2.0mmol/L,Trig 8.0mmol/L对本法无明显干扰。结论 本法具有简便、准确、快速，适用于自动分析等特点。     

液体单试剂酶法测定血清碳酸氢根

目的建立一种稳定的单试剂酶法测定血清碳酸氢根（HCO3^-）。方法利用自配单试剂建立了两点法的检测方法，可满足全自动和手工测定，用Bayer 1650生化仪对本方法进行方法学评价。结果本法的线性范围可达50mmol／L，批内变异系数（CV）为2．48％，批间CV为3．24％，平均回收率102．8％，与血气分析仪（X）相关良好，Y=1．019X-0．745，r=0．9903，黄疸、脂血、溶血标本对结果几乎无影响，健康人静脉血HCO3^-浓度为21．5～32．3mmol／L。结论本法操作简便、反应特异、灵敏准确、试剂较稳定，适用临床检测。     

偶氮氯膦I测定血清钙

目的：建立灵敏度高、选择性好、试剂稳定的血清钙测定方法。方法：在pH9.6的2－氨基－2－甲基－1，3－丙二醇（AMP）缓冲介质中，以偶氮氯膦I作显色剂，8－羟基喹啉－5－磺酸为掩蔽剂，分光光度法测定血清钙。对反应条件和方法性能进行系统研究。结果：该方法显色络合物最大吸收波长为580nm，线性血清钙。对反应条件和方法性能进行系统研究。结果：该方法显色络 的最大吸收波长为580nm，线性范围达5．0mmol/L，回收率为98．8％－99．1％，平均99．0％。批内变异系数（CV）和批间变异系数（CV）分别为0．95％和1．74％。与邻甲酚酞络合酮（OCPC）（X1）比较：Y＝1．003X1－0．036，r=0.996;与偶氮肿Ⅲ（X2）比较：Y＝1.001X2-0.030,r=0.997；与酶速率（X3）法比较：Y＝0.999X3-0.045,r=0.998。在血清胆红素高达412μmol/L,血红蛋白7g/L，镁2．59mmol/L及Intralipid高达8g/L时均对该法无显著干扰。结论：该法具有简便、快速、试剂稳定和灵敏可靠的优点，适合血清钙的手工测定和自动分析。     

采用修饰的ICD酶促法测定血清镁

已知Mg2+可激活300多种酶．到目前为止测定血清Mg2+的酶有：已糖激酶．葡萄糖激酶，甘油激酶和葡萄糖磷酸变位酶．用这些酶建立的酶法存在测定时间长，受干扰等缺点．故常规应用不能令人满意，为克服上述缺点本文介绍用化学修饰的异柠檬酸盐脱氢酶（ICD）简便快速地测定血清Mg2+，测定反应原理：以340um测定NADPH产生的吸光度，血清Mg2+浓度与吸光度的增加呈正比。试剂试剂I，0．2mol/L。pH8．0HEPES－TEA缓冲液，含0．67kU／L，修饰的ICD，6.7mmol／L异柠檬酸钾。试剂D．IOmn。of／I，pH60EDTA－Na。10Ommol／I。乙醇醚二…     

脲酶和亮氨酸脱氢酶偶联法动力学测定血清或尿液中尿素

目的　建立适合于自动化分析血清和尿液尿素的脲酶和亮氨酸脱氢酶偶联的连续监测法。方法　对pH、2 酮基异乙烯酸钠、亮氨酸脱氢酶和脲酶浓度等反应条件进行实验研究 ,并对建立的方法进行评价。结果　用双试剂连续监测法 ,试剂Ⅰ :10 0mmol/LN ,N 二乙醇胺基乙酸缓冲液 (pH 8.80 ) ,含 2 酮基异乙烯酸钠 3.0mmol/L、NADH 0 .3mmol/L、亮氨酸脱氢酶 2 .0kU/L。试剂Ⅱ :试剂Ⅰ中加入脲酶 70kU/L。本法线性范围血清 0 .5～ 15 0mmol/L ,尿液 8.0～ 6 5 0mmol/L。血清和尿液的平均回收率分别为 10 2 .1%和 10 1.5 %。血清批内和批间平均CV分别为 1.0 2 %和 1.70 % ;尿液批内平均CV为 1.98%。本法 (Y)和脲酶偶联谷氨酸脱氢酶法 (X)对比相关良好 (血清Y =0 .992X +0 .0 4 0 ,r=0 .993;尿液Y =0 .990X +0 .6 1,r=0 .991)。胆红素 <32 5 μmol/L、血红蛋白 <5g/L、抗坏血酸 <80 0 μmol/L、三酰甘油 (TG) <7.5mmol/L和NH+ 4 <0 .5mmol/L对测定无明显干扰。结论　本法简便、准确、线性范围广 ,可用于常规自动分析。     

液体单试剂酶法测定血清碳酸氢根

目的建立一种稳定的单试剂酶法测定血清碳酸氢根(HCO3-)。方法利用自配单试剂建立了两点法的检测方法,可满足全自动和手工测定,用Bayer 1650生化仪对本方法进行方法学评价。结果本法的线性范围可达50 mmol/L,批内变异系数(CV)为2.48%,批间CV为3.24%,平均回收率102.8%,与血气分析仪(X)相关良好,Y=1.019X-0.745,r=0.990 3,黄疸、脂血、溶血标本对结果几乎无影响,健康人静脉血HCO3-浓度为21.5~32.3 mmol/L。结论本法操作简便、反应特异、灵敏准确、试剂较稳定,适用临床检测。     

一种简便、灵敏的测定血清及尿液尿素的方法

目前,测定血清及尿液尿素的方法主要有二乙酰-肟法和偶酶联法,前者存在使用腐蚀性试剂、反应必须加热进行等缺点,故难以用于自动生化分析仪,后者虽能进行自动化分析,但试剂成本较高。且由于二者受方法线性范围的限制,测定尿液时都必须先行稀释标本。作者根据尿素酶水解尿素释放出的氨引起反应体系pH 升高这种情况,选择合适的缓冲液和pH 指示剂,建立了一种快速、简便、灵敏的比色分析力法,本法的最大特点是尿液无需稀释,且试剂成本低廉,它不但适用于手工操作,也可进行自动化分析。试剂:1.显色液——内含邻钾酚酞络合剂(OCPC)2.5mmol/L、EDTANa_4 5mmol/L、Tris 30mmol/L 及叠氮钠15.4mmol/L,用1mol/L     

低密度脂蛋白胆固醇的直接测定法

目的　建立直接测定血清低密度脂蛋白胆固醇 (LDL C)的方法。方法　基于选择性水解法的原理 ,通过对多聚体和表面活性剂的筛选和测定条件的优化实验确定了方法。结果　本法反应达终点的时间为 180s ,线性达 11 7mmol/L ,批内CV <1 6 4% ,日间CV <2 6 5 % ,总CV <3 38% ,回收率平均为 99 7%。和日本一化试剂比较 :Y =0 94X 0 0 32 ,r =0 975 ,n =5 2。本法的特异性好 ,加入LDL C达 3 9mmol/L ,VLDL Trig达 19 5mmol/L ,抗坏血酸 <2 84mmol/L、血红蛋白<5g/L和胆红素 <340 μmol/L时无显著干扰。 结论　本法的总误差 <7 40 % ,达到NCEP提出的 <12 %的分析目标 ,标本无需预处理 ,适合全自动分析     

Lipid peroxidation of the liver in liver disease

Material of puncture biopsy of the human liver left after morphological study was used to explore enzymatic and non-enzymatic lipid peroxidation, NADH-ferricyanide reductase activity, the content of triglycerides, cholesterol and protein. It was shown that the degree of lipid peroxidation varies considerably in different liver diseases. The highest degree of lipid peroxidation was discovered in patients with fibrosis accompanied by the symptoms of fatty dystrophy. It was established that the rate of peroxidation does not directly correlate with the level of liver lipid infiltration. It is concluded that NADH-ferricyanide reductase activity mirrors adequately the nature of a liver disease and can be used as a highly sensitive and very specific enzymatic test.     

Alcohol and the liver

Since ethanol metabolism predominantly takes place in the liver it is not surprising that hepatic intermediary metabolism is strikingly influenced. Alcohol is metabolized via three enzyme systems: alcohol dehydrogenase (ADH), microsome ethanol oxidizing system (MEOS) and catalase. The ADH reaction produces reducing equivalents as NADH which results in various metabolic disorders such as hyperproteinemia IV and V, hypoglycaemia, lactacidosis, hyperuricaemia, and certain forms of porphyria. The metabolism of hormones is also disturbed. Alcohol fatty liver is a direct consequence of NADH production. Alcoholic liver disease comprises of fatty liver, alcoholic hepatitis and cirrhosis. Risk factors of alcoholic liver disease are the amount of alcohol consumed, drinking pattern, female gender and certain genetic predispositions. Alcoholic hepatitis is characterized by a typical clinical and laboratory feature, and specific heaptic morphology. Poor prognostic factors are continuous alcohol consumption, cholestatis and perivenular fibrosis. Alcoholic cirrhosis has similar complications as cirrhosis of other etiology. Therapy includes abstinence, antioxidative drugs, steroids, and S-adenosylmethionine. Liver transplantation is of long-term benefit.     

Fat in the liver and insulin resistance

Insulin resistance in humans is not always accompanied by obesity, since severe insulin resistance also characterizes patients lacking subcutaneous fat such as those with HAART- (highly-active antiretroviral therapy)-associated lipodystrophy. Both obese and lipodystrophic patients, however, have an increase in the amount of fat hidden in the liver. Liver fat content can be accurately quantified non-invasively by proton magnetic resonance spectroscopy. It is closely correlated with fasting insulin concentrations and direct measures of hepatic insulin sensitivity while the amount of subcutaneous adipose tissue is not. An increase in liver fat content has been shown to predict type 2 diabetes, independently of other cardiovascular risk factors. This is easily explained by the fact that the liver, once fatty, overproduces most of the known cardiovascular risk factors such as very low density lipoprotein (VLDL), glucose, C-reactive protein (CRP), plasminogen activator inhibitor-1 (PAI-1), fibrinogen and coagulation factors. The causes of inter-individual variation in liver fat content, independent of obesity, are largely unknown but could involve differences in signals from adipose tissue such as in the amount of adiponectin produced and differences in fat intake. Adiponectin deficiency characterizes both lipodystrophic and obese insulin-resistant individuals, and serum levels correlate with liver fat content. Liver fat content can be decreased by weight loss and by a low as compared to a high fat diet. In addition, treatment of both lipodystrophic and type 2 diabetic patients with peroxisome proliferators activator receptor-gamma (PPARgamma) agonists, but not metformin, decreases liver fat and markedly increases adiponectin levels. The fatty liver may help to explain why some but not all obese individuals are insulin resistant and why even lean individuals may be insulin resistant, and thereby at risk of developing type 2 diabetes and cardiovascular disease.     

Sarcoidosis and sarcoid-like granulomas in the liver

Based on examination of 2450 liver biopsy specimens it has been shown that different granulomas occur in 4% of all the biopsy specimens. Of these, sarcoid-like granulomas are detectable in 13.5% of cases. Diagnosis of liver sarcoidosis is always based on the clinicomorphological findings with regard to an injury to at least of one more organ or tissue characteristic for such a disease. Sarcoid impairment of the liver is not infrequently coupled with chronic liver disease. The greatest difficulties may occur in differential diagnosis between primary biliary cirrhosis and sarcoidosis.