环境水样中硬度与碱度的测定与计算

提出了一种测定环境水样中总硬度,永久硬度及暂时硬度的新方法。与传统方法相比,该方法对环境水样更有针对性,能避免其他干扰条件引起的正误差,测定更准确。     

镜检脑脊液白细胞定量计数方法改进的研究

目的:建立手工法镜检脑脊液白细胞定量的快速、准确、直观的检测方法,并验证该方法比传统方法准确并可靠性高。方法:无菌条件下采集患者脑脊液标本230例,分别采用中华人民共和国卫生部医政司出版的《全国临床检验操作规程》上的规程法、定量法。两种方法对于同一样本进行白细胞数计数,实验重复3次,用单因素方差分析进行统计学比较。结果:镜检脑脊液白细胞计数定量的方法比传统的方法(P>0.05,sd,cv值更小)更准确精密可靠。结论:计数定量的方法比规程法更准确,精密,可靠。     

细菌人工染色体基因组文库构建方法的改进

目的:建立一种改进的更简便、易操作的细菌人工染色体(BAC)文库构建方法。方法:在构建猪霍乱沙门氏菌基因组大片段DNA的BAC文库时,对改进的基因组BAC文库构建方法和常规的BAC文库构建方法进行比较。结果:利用改进的方法可简便快速地构建猪霍乱沙门氏菌基因组BAC文库。结论:使用2种方法构建BAC文库,其转化效率,以及在BAC克隆中插入的DNA片段的大小和BAC克隆的稳定性等都相同,从而表明改进的方法更简单、更方便,它能使BAC文库的构建更为高效。     

慢病毒载体法制备遗传工程猴和小型猪的现状及应用前景展望

较小鼠等啮齿类动物而言,猴和小型猪等大型实验动物在亲缘关系上与人类更为接近,在解剖、生理生化代谢及疾病发病机制等多方面与人类更接近,使它们在复制人类疾病模型,研究疾病发病机制和新药研发等中有无可替代的应用。而制备遗传工程大动物可以更深入地解析人类疾病,并可为器官移植和新药研发提供更充分的实验材料。基于慢病毒介导的转基因方法近几年已越来越多地被用来制备遗传工程猴和小型猪。与传统的原核显微注射方法和体细胞核移植法相比,慢病毒介导的转基因方法转基因效率高,操作更简单。因此,构筑基于慢病毒介导的转基因方法制备遗传工程猴和小型猪的技术平台将对生物医学研究产生巨大推动作用。     

蛋白质印迹法的应用

本文介绍了蛋白质印迹法的新近应用。并希望这一方法能启发人们的思想,使其应用更迅速、更完善地扩展到生物学科的各个方面。     

对初中生物实验教学方法的运用与思考

生物实验是生物学形成和发展的基础,而生物学实验课程的开展则为学生提供了理论与实践相结合的平台。为了探究更有效更科学的生物学实验教学方法,本文阐述了我们在初中生物实验教学中所用的主要方法,并进行了相应的总结和补充。     

紫色非硫细菌固体石蜡双层平板培养法

紫色非硫细菌是一类不产氧光合细菌,具有重要的生态学意义和应用价值。建立固体石蜡双层平板法,与传统的培养法相比较,发现该方法可以更方便、更快捷地计数和分离紫色非硫细菌。结合分子生物学技术,将该方法应用于水稻土紫色非硫细菌的研究,发现以甲酸为碳源的固体石蜡双层平板法可以很好地对环境中可培养的紫色非硫细菌多样性进行研究。该方法的建立将更有助于紫色非硫细菌的研究。     

核酸疫苗制备卵黄免疫球蛋白研究进展

卵黄免疫球蛋白(Ig Y)由于其独特的分子结构和稳定性能,使得Ig Y的制备成为抗体领域的研究热点。核酸疫苗作为一种新型疫苗,在生产成本、免疫剂量和免疫保护力等方面比大多数传统疫苗更具有优势。核酸疫苗制备Ig Y结合了两者的优点,比常规免疫方法更具有优势,产生的Ig Y适用范围也更广。本文综述了一种经济、快速的Ig Y制备方法:核酸疫苗制备Ig Y。     

地区农业耕作模式的综合评价优化法

提出一种系统的综合评价方法对广东三水市种植业18种耕作模式进行综合评价．该法克服了仅用一种方法在评价中的片面性,使评价结果更加全面、客观,同时解决了评价结果总存在差异的现象．此外,还提出用指标客观权重进行综合评价更合理、更可靠．     

应用蒙特卡洛方法对黑龙江创业农场水稻单产变化的预测

应用蒙特卡洛方法对创业农场水稻单产进行模拟计算和预测,这样的预测结果较其它方法更接近于实际的结果．     

造血细胞活力冷冻损伤的可恢复性

人骨髓冻存后其造血祖细胞活力有一定程度下降,本研究对这种下降的可逆性作了初步观察。结果发现,用双层法和单层法作CFU-GM培养时,未冻存骨髓集落产率相近,冻存骨髓双层法的CFU-GM产率高于单层法。骨髓细胞用20％FM-CM、PHA-LYCM、PHA-PMCM预孵育2h后,分别测定其CFU-GM、BFU-E与CFU-Mix,发现这种孵育过程对未冻存骨髓的集落产率无明显影响,而冻存骨髓的集落产率在孵育后可升高(GEMmeg除外)。说明骨髓造血祖细胞对冻存的损伤反应不均一,部分受损细胞在一定条件下可以恢复其增殖活力。这对于用冻存骨髓作骨髓移植可能有一定意义。     

潜生体定植的原位观察技术研究

对小鼠结肠组织原位标本进行潜生体定植的实验研究。染色采用美蓝初染后,高锰酸钾复染的方法。方法简便、有效。     

DEVELOPMENT OF A NEW BIOSENSOR FOR DETERMINATION OF CATALASE ACTIVITY

Catalase is one of the major antioxidant enzymes that catalyzes the hydrolysis of H₂O₂. The aim of this study was to suggest a new method for the assay of catalase activity. For this purpose, an amperometric biosensor based on glucose oxidase for determination of catalase activity was developed. Immobilization of glucose oxidase was made by a cross-linking method with glutaraldehyde on a Clark-type electrode (dissolved oxygen probe). Optimization and characterization properties of the biosensor were studied and determination of catalase activity in defined conditions was investigated in artificial serum solution. The results were compared with a reference method.     

DETECTION AND DEMONSTRATION OF INHIBITORY ACTIVITIES OF BACTERIOCINS BY ISOELECTRIC FOCUSING

A technique utilizing isoelectric focusing (IEF) was developed and compared with a modified Bhunia's sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) method for directly detecting antimicrobial activities of inhibitory peptides or proteins (bacteriocins). In IEF, the gel containing separated peptide or protein bands was directly overlaid with indicator bacteria without any fixation or rinsing as done in the SDS-PAGE method. The IEF gave clear zones of inhibition surrounding inhibitory bands. Bhunia's method was modified to reduce the time for fixation and rinsing, and a 15-min fixation followed by 2-h rinsing with dd H₂O was determined to be necessary for a detection similar to the IEF. In addition, results of this study showed that denaturation of bacteriocins and, subsequently, failure to detect the presence of a bacteriocin could occur in the SDS-PAGE analysis while little denaturation was observed in the IEF assay. Therefore, the IEF assay developed in this study was more rapid and less destructive as compared with the SDS-PAGE method.     

细菌透析袋表面培养法及其蛋白质产物的检测

本文报告的细菌透析袋表面培养法,可使被检菌的浓度比普通培养法高10倍左右,并避免了培养基中高分子物质混入,以上清原液直接进行SDS-PAGE得到了清晰的带谱。对葡萄球菌产生的蛋白质带谱观察显示:不同菌种、菌株间带谱都有各自不同特征,各菌株的带谱重复性良好。本培养法在细菌蛋白质产物分析及临床细菌鉴定中是很有实用价值的。     

RADIATION THERAPY OF RINGWORM OF THE SCALP

A recent epidemic of tinea capitis in children has revived a considerable interest in the methods of treatment of this disease.The most efficacious form of therapy for M. audouini infections is roentgen epilation.The various methods of x-ray treatment are briefly presented and compared. A modification of the four-point technique is shown to offer a simple yet safe method of curing ringworm of the scalp. Results with this method compare favorably with the best of those reported by the use of other methods.Cure was effected by this method in all of a group of 125 cases.     

COMPARISON OF SIMPLIFIED METHODS FOR EVALUATION OF SENSORY THRESHOLDS OF ADDED SUBSTANCES

Results obtained in the determination of sensory thresholds with three different simplified methods were compared. The methods were: a modification of the ascending method of limits (1), one based on the method of the constant stimuli (2), and one based on the use of scales (3). The study was carried out on two sensorially simple systems, sucrose and aspartame aqueous solutions. The thresholds values for sucrose obtained by method 1 (1.41 g/L) and by method 2 (1.60 g/L) were similar and within the range obtained by method 3 (0.6–1.6 g/L). For aspartame the values obtained with methods 1 and 2 were also similar (0.004 and 0.005 g/L, respectively), but they were below the minimum value of the corresponding range (0.008–0.016 g/L) calculated with method 3. These results suggest that the sensory methods provoked less variability in thresholds values than other noncontrolled factors. The limitations and advantages of each method are discussed considering: experimental work, precision of results and practical validity.     

ASSESSMENT OF IMPEDANCE MICROBIOLOGICAL METHOD FOR THE DETECTION OF ESCHERICHIA COLI IN FOODS

This study was conducted to determine the sensitivity and specificity of the impedance-based microbiological method for the detection of Escherichia coli in foods within 24 h of testing. A Malthus Microbiological Analyzer system (Malthus System V, Malthus Instruments Ltd., Bury, United Kingdom), and a modified Malthus Coliform Broth Medium (MCBM), and an incubation temperature of 44C were used. The sensitivity of the impedance method was determined by testing E. coli-negative food samples spiked with different concentrations of E. coli. The specificity of the method was determined by testing E. coli -negative food samples spiked with Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa. The test results were compared with those obtained by the Most Probable Number (MPN) method. Milk, milk products, raw and ready-to-eat meats, and vegetables were tested for the presence of E. coli by both methods. The sensitivity of the impedance method and the MPN method for the detection of foods containing 10¹ CFU/g was 100% and 84.4%, respectively. Both methods had a specificity of 100% for food samples spiked with 10¹ CFU/g E. coli. The specificity of the impedance and the MPN methods for the detection of E. coli in naturally contaminated milk and meat samples was 100% and 95.7% respectively. E. coli was detected in foods by the impedance method within 4–24 h of testing at a detection limit of 1 CFU/mL. These results demonstrate that the impedance method can be used as a rapid and sensitive method for the detection of E. coli in foods.     

真空负压ABC法在各种组织相关抗原检测的应用研究

在免疫组化染色过程中,如何把各组织中的相关抗原充分地显示出来,许多免疫组化工作者进行了各种方法的探讨。但是,其结果却不十分理想,主要问题是染色的背景深及组织切片容易脱离载片,造成染色的失败。真空负压在免疫组化染色过程中的应用,能减少步骤,缩短时间,消除非特异性染色,使背景清晰,易于判断结果。并且避免了组织切片脱落现象,还可提高某些抗体的稀释度。此法均可使用金属性或非金属性器皿,而且整个过程都可在室温中进行,比微波技术更为简便易行,安全可靠,实用性强,成本低,有较大的推广价值。     

EVALUATION OF EXPOSURE TREATMENT OF BURNS

For purposes of comparison with the occlusive dressing method of treating burns, the exposure method was used in 30 cases—16 of first and second degree and 14 of third degree. Attempt was made to simulate the conditions which might be expected to prevail in mass treatment of burned patients—inadequate personnel and materials. Elaborate measures to immobilize burned areas were not employed.Healing of first and second degree burns was natural and the results satisfactory without further treatment. In third degree burns, skin grafting was necessary after the eschar was removed. Cracking of the eschar several days before time to remove it in some cases of third degree burns necessitated use of occlusive dressings in the last few days before skin grafting was done.The exposure method is considered valuable in circumstances in which saving of time, material and personnel is indicated. Generally it is not suitable for treatment of encircling burns of the trunk or extremities, since maintaining the integrity of the eschar is extremely difficult in such situations.