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71.
建立毛细管电泳分离分析多巴胺和 5一羟色胺的方法。采用自由区带电泳法 (CZE) ,4 0mmol/L硼砂缓冲液 2 0PSI气压进样 5s ,定电流 75 μA分离 10min ,二极管阵列PDA检测器检测 ,应用 2 0 0nm检测波长 ,结果显示两种物质完全分离。 相似文献
72.
Kolak M Karpati F Monstein HJ Jonasson J 《International journal of medical microbiology : IJMM》2003,293(4):309-317
Despite recent advances in therapy, lower airway infections remain the major cause of morbidity and mortality in cystic fibrosis (CF) patients. Bacterial colonisation of the lower airways in CF is limited to a few bacterial species, commonly Staphylococcus aureus, Pseudomonas aeruginosa and Haemophilus influenzae. Burkholderia cepacia colonisation is much rarer, but it has been thought to be associated with more advanced lung disease and increased mortality. A rapid characterisation of the bacterial flora in sputum of CF patients is of great importance for proper treatment. The aim of this study was to establish bacterial profiles and to identify pathogenic bacteria in respiratory specimens by means of molecular methods including temporal temperature gradient gel electrophoresis (TTGE) and DNA sequencing of PCR amplicons derived from 16S rDNA variable V3 and V6 regions. Sputa of 13 CF patients (7 males/6 females, age 19-59 years) collected at the Stockholm CF centre were analysed. TTGE revealed the presence of complex bacterial profiles in all samples. The V3 and V6 PCR amplicons were cloned and sequenced by real-time DNA Pyrosequencing. DNA from Staphylococcus aureus, Haemophilus influenzae, and Pseudomonas aeruginosa, respectively, was identified together with sequences from normal oral cavity flora. The results were in reasonable agreement with those obtained by conventional bacterial culture, considering that only known CF pathogens are included in routine reports. However, the methodology seems too elaborate to be introduced into daily routine 相似文献
73.
Nobukazu Tamaki 《European journal of applied physiology》1987,56(2):127-131
Summary Muscle fiber type composition and capillary supply in rat diaphragm were investigated after 14 weeks of endurance training: body weight and muscle fiber area were significantly decreased, the muscle fiber type composition, capillary to fiber ratio and number of capillaries around each fiber type were unchanged, and the capillary density and number of capillaries around each fiber relative to fiber type areas were significantly increased. These small fiber areas and increased capillary supplies in the trained rats would facilitate oxygen transport to all parts of the muscle fiber during exercise. It is concluded that the changes observed in the trained rat diaphragm appear to enhance the capacity for oxidative metabolism. 相似文献
74.
G. N. Kryzhanovskii V. I. Fedorova R. N. Glebov R. M. Kulygina O. P. Sakharova 《Bulletin of experimental biology and medicine》1975,79(4):367-370
It was shown by electrophoresis on polyacrylamide gel that the content of proteins with low electrophoretic mobility rises in a Triton extract of the fractions of synaptic structures from the spinal cord tissue of rats with local tetanus, whereas no change was found in the protein spectrum in the dodecyl sulfate extract. In experiments in vitro tetanus toxin stimulated the incorporation of lysine-H3 into total proteins of cortical synaptosomes.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 79, No. 4, pp. 19–22, April, 1975. 相似文献
75.
76.
In the search for a serology tool for the diagnosis of nonpatent as well as patent infections with Oesophagostomum dentatum in pigs a water-soluble, unglycosilated antigen of about 30 kDa specific for the third-stage larvae of the parasite was purified
by ion-exchange chromatography. In Western blots, the antigen was first detected by antibodies at day 7 postinfection. Cross-reactivity
with O. quadrispinulatum, Ascaris suum, or Trichuris suis was not detected. It is suggested that this protein is a suitable tool for the species-specific serodiagnosis of O. dentatum infection in pigs.
Received: 15 June 1998 / Accepted: 28 September 1998 相似文献
77.
大鼠肝再生过程中碱性磷酸酶活性变化及其超微细胞化学研究 总被引:4,自引:0,他引:4
目的 研究2/3肝切除后大鼠肝再生过程中碱性磷酸酶(AKP)活性的变化及其细胞定位。方法 利用比色法对AKP活性进行定量分析;用酶的原位复性电泳技术分析再生肝中AKP的种类和活性变化;用电镜细胞化学方法研究酶定位。结果 在肝部分切除后的肝再生期间,AKP出现两个活性高峰(16h和19h),在每个活性高峰后,AKP均有显著下降;获得3种肝型AKP同工酶(140、160和180kD),其中180kD的AKP只在肝再生过程中出现;随着肝再生的进展,AKP活性出现在细胞的不同部位。结论 AKP在肝再生过程中起重要作用,可能参与细胞代谢、物质转运、DNA合成和细胞分化。 相似文献
78.
M. A. Livesley S. E. Tebbs H. A. Moss M. H. Faroqui P. A. Lambert T. S. J. Elliott 《European journal of clinical microbiology & infectious diseases》1998,17(2):108-112
Microorganisms detected in situ on the distal tip of central venous catheters (CVC) within 90 min of insertion were investigated using pulsed-field gel electrophoresis to analyse genomic fragments obtained with theSmaI restriction enzyme. Thirty patients received a triple lumen CVC, which was inserted directly through the skin using the Seldinger technique. In a further 30 patients a triple lumen CVC was inserted through a Swan sheath, thereby avoiding direct contact of the CVC with the skin. Staphylococci were isolated from the distal tips of the catheters in 6 patients (5 who had the CVC inserted directly through the skin and 1 who had the CVC inserted via a Swan sheath.) Twenty-three staphylococcal isolates were also isolated from the insertion equipment and the skin swabs surrounding the insertion site of these six patients. All the isolates were genotyped. In one of the patients the organisms isolated from the skin were identical to those on the CVC tip. In two further patients similar organisms were isolated from the insertion equipment and the patients' skin. These results, in addition to the reduced colonisation rates observed when catheters were introduced through a Swan sheath, support the hypothesis that microorganisms from the skin are impacted onto the CVC tip and the CVC insertion equipment at catheter insertion. 相似文献
79.
R Cigén 《Molecular immunology》1985,22(9):1039-1043
The structural difference between two forms (basic and acidic) of guinea-pig beta 2-microglobulin (beta 2m) has been established. Both forms are present in urine from inbred guinea-pig strains. The beta 2m forms were each digested with carboxypeptidase Y and carboxypeptidase A contaminated with carboxypeptidase B. Released amino acids were separated from remaining protein, dansylated and analysed by 2-dimensional TLC on polyamide layer sheets. From the results it was concluded that the basic beta 2m form has lysine and the acidic beta 2m form has asparagine as their respective C-terminal amino acids. The acidic form is also 1 amino acid (lysine) shorter than the basic form, which is supported by electrophoretic studies on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The presence of the 2 forms of beta 2m in urine from inbred guinea-pig strains 2 and 13, shown by gel filtration and ion exchange chromatography, makes it unlikely that the 2 forms are a result of genetic polymorphism. 相似文献
80.
Capillary array electrophoresis (CAE) is a novel technique, which allows for high throughput analysis of DNA fragments. When screening for mutations in whole populations or large patient groups it is necessary to have robust and well-characterized setups for high throughput analysis. For large-scale mutation screening, we have developed procedures for single strand conformation polymorphism (SSCP) assays using CAE (CAE-SSCP) whereby we may increase both the sensitivity and the throughput compared to conventional SSCP analysis. In this study we have validated CAE-SSCP by 1) comparing detection by slab-gel based SSCP with CAE-SSCP of mutations in the MYH7, MYL2, and MYL3 genes encoding sarcomere proteins from patients suffering from hypertrophic cardiomyopathy; and 2) by constructing a series of 185 mutants having substitution mutations, as well as insertion/deletion mutations, or some combinations of these, in different sequence contexts in four exons and different positions relative to the end of the amplicon (three from the KCNQ1 gene, encoding a cardiac potassium channel, and one from the TNNI3 gene encoding cardiac troponin I). The method identified 181 out of 185 mutations (98%), and the data suggest that the position of mutation in the fragment had no effect on the sensitivity. Analysis of the specificity of the method showed that only very few mutants could not be distinguished from each other and there were no false positives. 相似文献