Estimation of cardiac output by the CO2 rebreathing method during tethered swimming

The reproducibility of cardiac output (Q) estimated by the CO2 rebreathing method during tethered swimming was studied in five highly trained college swimmers. The reproducibility of the CO2 rebreathing method for estimations of Q during tethered swimming was similar to the reproducibility reported for the CO2 rebreathing method, direct Fick method, or dye-dilution method during either cycling or treadmill walking. All duplicate estimates of Q by the CO2 rebreathing method were within 15% of one another. A comparison was made between the Q's estimated by the CO2 rebreathing method during tethered swimming and previously published data on Q determined by the dye-dilution method during free swimming in a flune. At any given oxygen uptake, Q obtained by the CO2 rebreathing method during tethered swimming was not significantly different from the Q obtained by the dye-dilution method during flume swimming. Estimates of Q by the CO2 rebreathing method made during high intensities of tethered swimming were reproducible and appear to be valid.     

Comparative Study of Responses to Neomycins B and C by Microbiological and Gas-Liquid Chromatographic Assay Methods

The relative responses of neomycins B and C have been determined by a microbiological agar-diffusion method, a turbidimetric method, and by a recently developed gas-liquid-chromatographic (GLC) method capable of separating the neomycin isomers. The ratios of response of neomycin C to neomycin B by the individual methods were as follows: agar-diffusion method, 1:3; turbidimetric method, 1:2.5; and GLC method, 1:1. When neomycin C is assumed to have 35% biological activity of neomycin B, the calculated drug contents of neomycin sulfate powders obtained by the GLC method correlated well with values obtained by the microbiological agar-diffusion assay method.     

Interaction amongst calcineurin subunits. Stimulatory and inhibitory effects of subunit B on calmodulin stimulation of subunit A phosphatase activity depend on Mn2+ exposure of the holoenzyme prior to its dissociation by urea

Calcineurin was dissociated into subunits A and B by 6 M urea in the presence (method A) and absence (method B) of MnCl2 and dissociated subunits were isolated by gel filtration in urea in the absence (method B) or presence (method A) of MnCl2. Phosphatase activity was associated with the A subunit isolated by either method. The phosphatase activity (nmol/mg) of subunit A isolated by method A was greater (2-5-fold) than by method B. Mn2+ increased subunit A phosphatase and calmodulin further increased the enzyme activity. Subunit B isolated by method A or B increased Mn2+ + calmodulin stimulated subunit A phosphatase prepared by method B but interestingly and unexpectedly inhibited such stimulated activity of the subunit A prepared by method A. These results imply the tightly bound cation (in our case, most likely Mn2+) with subunit A dramatically and differentially influences the effects of two Ca2+-binding proteins, calmodulin and subunit B, on the subunit A phosphatase.     

条斑紫菜丝状体总RNA提取方法比较

目的:为了获得质量较高的条斑紫菜丝状体总RNA,对几种常用提取方法进行研究。方法:以条斑紫菜自由丝状体为材料,比较了用异硫氰酸胍法、CTAB法、SDS/酚法、TRIzol法、RNAplant法提取的RNA的质量和纯度。结果:异硫氰酸胍法提取RNA的成本低,但纯度不高;CTAB法产率较小,且不能完全去除多糖或蛋白质;SDS/酚法未能获得完整的RNA;TRIzol法未能见到5SrRNA条带,且带有杂带;而RNAplant法提取RNA的质量好、纯度高、提取效率高,其D260nm/D280nm值为1.836,经逆转录得到的双链cDNA扩增产物长度在200bp以上。结论:实验结果表明RNAplant法更适于条斑紫菜丝状体总RNA的提取。     

Recovery of DNA from soils and sediments

Experiments were performed to evaluate the effectiveness of two different methodological approaches for recovering DNA from soil and sediment bacterial communities: cell extraction followed by lysis and DNA recovery (cell extraction method) versus direct cell lysis and alkaline extraction to recover DNA (direct lysis method). Efficiency of DNA recovery by each method was determined by spectrophotometric absorbance and using a tritiated thymidine tracer. With both procedures, the use of polyvinylpolypyrrolidone was important for the removal of humic compounds to improve the purity of the recovered DNA; without extensive purification, various restriction enzymes failed to cut added target DNA. Milligram quantities of high-purity DNA were recovered from 100-g samples of both soils and sediments by the direct lysis method, which was a greater than 1-order-of-magnitude-higher yield than by the cell extraction method. The ratio of labeled thymidine to total DNA, however, was higher in the DNA recovered by the cell extraction method. than by the direct lysis method, suggesting that the DNA recovered by the cell extraction method came primarily from active bacterial cells, whereas that recovered by the direct lysis method may have contained DNA from other sources.     

Recovery of DNA from soils and sediments.

Experiments were performed to evaluate the effectiveness of two different methodological approaches for recovering DNA from soil and sediment bacterial communities: cell extraction followed by lysis and DNA recovery (cell extraction method) versus direct cell lysis and alkaline extraction to recover DNA (direct lysis method). Efficiency of DNA recovery by each method was determined by spectrophotometric absorbance and using a tritiated thymidine tracer. With both procedures, the use of polyvinylpolypyrrolidone was important for the removal of humic compounds to improve the purity of the recovered DNA; without extensive purification, various restriction enzymes failed to cut added target DNA. Milligram quantities of high-purity DNA were recovered from 100-g samples of both soils and sediments by the direct lysis method, which was a greater than 1-order-of-magnitude-higher yield than by the cell extraction method. The ratio of labeled thymidine to total DNA, however, was higher in the DNA recovered by the cell extraction method. than by the direct lysis method, suggesting that the DNA recovered by the cell extraction method came primarily from active bacterial cells, whereas that recovered by the direct lysis method may have contained DNA from other sources.     

Comparison of three methods detection of slime production by Staphylococcus aureus and Staphylococcus epidermidis

In this article, slime production of Staphylococcus aureus and Staphylococcus epidermidis strains from infective skin lesions was evaluated by three different methods: Congo red agar method (CRA), Christensen tube method (CT) and spectrophotometric method (SC). All strains by CT method interpreted as negative (dark-claret or red colonies of the surface). 12 (37.5%) strains of S. aureus, 16 (50.0%) strains of S. epidermidis produced slime as shown by CT method, 6 (18.7%) strains of S. aureus, 8 (25,0%) strains of S. epidermidis by SC method. They also found a correlation of slime production by CT and SC method (p > 0.05).     

快速提取类球红细菌中辅酶Q10的方法研究

目的：建立一种从类球红细菌中快速分离纯化辅酶Q10的方法。方法：对影响超声提取辅酶Q10的各因素,包括提取试剂、超声频率、循环次数及工作时间的最佳条件进行正交试验,比较超声破碎法与碱醇皂化法提取辅酶Q10的差异。结果：在超声提取中,提取试剂和循环次数对辅酶Q10提取效果具有显著性影响;在超声频率0.5s、丙酮提取3min、循环3次的条件下提取的辅酶Q10的含量比碱醇皂化法提高了近6倍。结论：超声破碎法是一种简单、迅速、高效的提取辅酶Q10方法。     

PCR特异产物回收纯化方法的比较

方法：采用三种方法对苹果褪绿叶斑病毒RT-PCR的特异DNA产物进行回收纯化。目的：针对不同情况,选择适宜的回收纯化方法。结果：用普通琼脂糖替代低融点琼脂糖,回收纯化后产物的浓度及纯度与低融点琼脂糖法基本一致,完全可以用普通琼脂糖替代低融点琼脂糖进行DNA片段的回收纯化,从而降低成本,简化操作。玻璃奶法的回收纯度明显高于低融点琼脂糖法和普通琼脂糖法,且更快速安全,是采用普通琼脂糖法还是采用玻璃奶法回收纯化DAN片段应以实际需要而定。     

啮齿动物的巢区面积估算法

巢区(Home range)是动物在其巢附近进行取食、生殖、育幼等日常活动的区域(Burt 1940)。标志流放法是应用最广的调查啮齿动物巢区的方法,尤其是按方格式布笼。但对同一野外调查结果,由于估算方法不同,巢区估算值相差很大,并且至今尚无学者提出一致公认的估算法。1980年5-10月,我们在青海省门源县的高寒草甸生态系统定位站调查根田鼠的巢区,按多种估算法对同一批实际调查结果估计了巢区面积,并对结果进行了分析比较,检查其特点和优缺点,并提出修正平均值法,作为我们今后讨论根田鼠巢区动态的基础。 对方格式布笼的调查结果进行巢区的估算方法,基本上分二大类,图形法和概率性模型法。图形法是按照捕点分布划出巢区,并直接求出巢区面积,如最小面积法,包括或不包括周边地带法,最大距离法和复合散布图法。     

T细胞亚群CD4测定方法的研究

为比较外周血T淋巴细胞亚群CD4不同测定方法的差别,以流式细胞术为定量手段,测定了猴外周血中三种不同方法处理后CD4的表达.结果表明：先标后溶法——先用异硫氰荧光素标记的单克隆抗体（FITC-CD4 McAb）标记后,再加入红细胞溶解液溶掉红细胞的处理方法,结果基本等同于传统的淋巴细胞分离法,但样本用量仅为传统方法的1/5,且操作简单.激光共焦显微术的形态学研究也证实：先标后溶法与淋巴细胞分离法相似,其细胞膜表面荧光标记清晰,优于先溶后标法.     

Use of a new methylene blue derivative for determination of lipid peroxides in foods

To determine lipid peroxides in chloroform-methanol extracts of foods, a simple and sensitive colorimetric method using a new leucomethylene blue derivative was adopted. The amounts obtained by this method coincided well with those by the iodometric method and paralleled those by the thiobarbituric acid method.     

洗发、护发化妆品微生物检查方法学研究

为提高化妆品潜在微生物的阳性检出率,建立洗发、护发类化妆品微生物限度和控制菌检查方法。采用常规法、培养基稀释法、薄膜过滤法对4种洗发、护发类化妆品进行微生物限度与控制菌方法学研究。结果显示,飘柔长效柔顺滋养洗发露、海飞丝去屑洗发露、飘柔人参滋养润发精华素、力士密集滋养修复-发膜级精华素菌落总数检测方法分别为0.2 m L/皿法、800 m L/膜法、0.5 m L/皿法和300 m L/膜法;霉菌及酵母菌检测方法分别为300 m L/膜法、300 m L/膜法、1 m L/皿法和1 m L/皿法;除海飞丝去屑洗发露采用培养基稀释法,其他均采用常规法进行控制菌检查。建议在化妆品微生物检验前应进行微生物方法研究,从而提高化妆品"潜在"病原菌的检出率。     

Rapid Semiquantitative Method for Screening Large Numbers of Virus Samples by Negative Staining Electron Microscopy

A rapid, semiquantitative method for screening large numbers of virus samples by negative staining electron microscopy is presented. Results obtained by this method are compared with results obtained by the pseudoreplica method and a measureddrop method. A figure is presented which represents the limit of detectability for virus by negative staining.     

蚧虫基因组DNA不同提取方法的比较

实验以日本龟蜡蚧CeroplastesjaponicusGreen,白蜡绵粉蚧PhenacoccusfraxinusTang ,朝鲜球蚧DidesmococcuskoreanusBorchseniush和瘤大球坚蚧EulecaniumgiganteaShinji等 4种蚧虫为材料 ,分别用十二烷基硫酸钠 (SDS)法、十六烷基三乙基溴化铵 (CTAB)法、醋酸钾 (KAc)法和氯化钠 (NaCl)法等 4种方法 ,对单只蚧虫进行基因组DNA提取 ,用 0 8%琼脂糖凝胶电泳检测所提DNA。结果表明 ,4种方法都可以提取到基因组DNA ,但是比较而言 ,CTAB法和NaCl法所提取的DNA质量明显优于SDS法和KAc法 ,并适用于PCR。因此认为 ,CTAB法和NaCl法是实验室提取单只蚧虫基因组DNA更有效而实用的方法。     

三种人全血基因组DNA提取方法的比较

目的：比较改良酚一氯仿抽提法、盐析法、试剂盒法从人全血中提取基因组DNA的效果,以期建立一种快速、经济的提取高质量基因组DNA的方法。方法：分别用上述三种方法从人全血中提取基因组DNA,通过紫外分光光度计、琼脂糖凝胶电泳、聚合酶链式反应（PCR）、限制性内切酶酶切检测提取的基因组DNA的产量、纯度和质量。结果：改良酚一氯仿抽提法与试剂盒法提取的基因组DNA相比,DNA的产量有统计学差异,DNA的纯度无统计学差异,但试剂盒法提取的基因组DNA有较明显的降解现象：盐析法与改良酚．氯仿抽提法、试剂盒法相比,基因组DNA的产量和纯度都存在统计学差异,并且基因组DNA聚合酶链式反应（PCR）扩增的稳定性也明显劣于另外两种方法;三种方法提取基因组DNA均能进行限制性内切核酸消化。结论：改良酚一氯仿抽据取法是一种经济、快速、高效、稳定提取人全血基因组DNA的方法,适用于批量临床标本处理。     

A method for characterizing ultrasonically-derived follicular data in heifers

A method was developed for ultrasonically characterizing follicular waves in heifers without the necessity of maintaining day-to-day identities of individual follicles (nonidentity method). Results were compared to a method in which the identities of individual follicles were maintained from day to day (identity method). Data collected daily during 5 estrous cycles were processed by each method, independently, by different operators. The nonidentity method involved grouping and then profiling follicles in order of decreasing diameters without regard to day-to-day identities. The profiling scheme distinguished between follicles of the left versus the right ovary. The dominant and subordinate follicles were readily distinguishable in the nonidentity profiles. When successive dominant follicles developed in the opposite ovary, the follicles were profiled directly. When two successive dominant follicles developed on the same ovary, size information was obscured for a few days where the profiles for each follicle crossed, but continuity of the profiles on each side of the area of ambiguity was maintained. The nonidentity method seemed equivalent to the identity method in determining characteristics of the dominant follicle (e.g., maximal diameter, growth rate, regression rate). Day of emergence of a wave and day of divergence in diameters between dominant and subordinate follicles were readily determined by inspection of the nonidentity profiles. A greater number of subordinate follicles per wave was detected by the nonidentity method due to the inability to individually identify all detected follicles by the identity method. Regression of follicles from a previous wave into the subordinate follicles of a succeeding wave was apparent by either method. The nonidentity method seemed suitable for most needs, was less tedious, and required less skill than the identity method.     

不同方法分离的成人睾丸支持细胞与胰岛共移植的效果对比

目的比较成人睾丸支持（Sertoli）细胞不同分离方法的效果,建立成人Sertoli细胞简便高效的分离方法。方法将质量相等的睾丸组织按照不同分离方法随机分为3组：A组采用胰蛋白酶、DNA酶、胶原酶和透明质酸酶一步消化法;B组采用胰蛋白酶和DNA酶第一步消化,胶原酶和透明质酸酶第二步消化;C组采用胰蛋白酶和DNA酶第一步消化,透明质酸酶第二步消化,胶原酶第三步消化;D组为对照组。采用形态学观察和免疫组化鉴定Sertoli细胞;MTT法和流式细胞仪法测定3组Sertoli细胞的活性和纯度;应用生存分析方法比较3组Sertoli细胞与胰岛共移植至糖尿病鼠的效果。结果分离获得的细胞经形态学和免疫组化鉴定,具有Sertoli细胞的特征,A、B、C三组Sertoli细胞的纯度分别为（85．17±1．8）％、（92．33±2．5）％和（93．12±2．6）％,B组和C组的Sertoli细胞纯度显著高于A组（t=7．35,t=7．95,P=0．00,P=0．00）。B组Sertoli细胞活性于培养14d时达到峰值,此后缓慢下降。B组Sertoli细胞活性显著高于A组和C组（t=4．02,t=2．77,P=0．00,P=0．01）,且B组Sertoli细胞与胰岛共移植术后胰岛移植物存活时间显著高于A、c、D组（F=165．548,P=0．000）。结论采用两步消化的方法能够获得纯度和活性较高的Sertoli细胞,其与胰岛共移植能够显著延长移植物存活。     

海南产桶形芋螺线粒体基因组DNA提取条件的优化

提取海南产桶形芋螺线粒体基因组完整DNA (mtDNA),并对提取条件进行优化。以桶形芋螺腹足肌肉、毒腺和肝胰脏三个不同组织为材料,分别采用改进高盐沉淀法、细胞器/磁珠法和试剂盒提取三种方法,提取桶形芋螺mtDNA,并利用琼脂糖凝胶电泳和紫外分光光度计对提取mtDNA的纯度和浓度进行测定。以coxⅠ-rRNA小亚基基因和α-芋螺毒素基因设计引物,通过PCR反应来确证所提取的DNA确实是mtDNA。试剂盒法提取肝胰脏、高盐沉淀法提取肝胰脏和腹足肌肉组织这三种方法的产率很高,分别为44.4μg/mg、43.3μg/mg和32.6μg/mg。A260/280比值表明,改进高盐沉淀法提取毒腺和腹足肌肉组织,细胞器磁珠法提取腹足肌肉组织的mtDNA纯度很高。综合比较,采用改进高盐沉淀法,利用桶形芋螺腹足肌肉组织所提取的mtDNA产率高、质量好、纯度高。高质量芋螺mtDNA的获取为利用分子生物学方法对芋螺进行遗传进化分析和系统分类提供了基础。     

Formation of Fine Oil-in-Water Emulsions by the Gel Emulsification Method with Saccharide and Protein

An emulsification method using a gel-like phase of a saccharide and protein mixture has been developed. In the method, which is called a gel emulsification method, an oil is added to the highly concentrated saccharide solution containing protein to form a clear gel-like phase, which followed by dilution with water to form a fine oil-in-water emulsion. This emulsion was investigated as to its emulsifying activity and emulsion stability as compared with that obtained by high-shear equipment, which was called a homomixer method. The emulsifying activity of the emulsions prepared by the gel emulsification method was much higher than that of the emulsions prepared by the homomixer method.

The emulsions prepared by both methods were highly stable in terms of the stability against coalescence. On the other hand, the stability against creaming of the emulsions prepared by the gel emulsification method was much higher than that of the emulsions prepared by the homomixer method.

The surface hydrophobicity of the protein and the unfreezable water content in the highly concentrated saccharide solution containing protein were not correlated to the emulsifying properties of the emulsions prepared by the gel emulsification method, which appeared to be dependent on the viscosity of the highly concentrated saccharide solution containing protein.