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91.
人细胞色素p450IA1基因cDNA的克隆和鉴定 总被引:5,自引:1,他引:4
在用3-甲基胆蒽诱导培养人羊膜FL细胞24h后,抽提细胞总RNA并直接合成cDNA第一链。利用人工合成的一对寡核苷酸引物,采用PCR技术特异性地扩增Cyt p50IA1 cDNA。30个循环后琼脂糖凝胶电泳显示1.5Kb大小片段,长度与预计相符。Southern杂交结果证实此片段确为Cyt p450IA1 cDNA。将此片段克隆至质粒pGEM-3Z并进行部份序列分析。结果显示克隆片段包含Cyt p 相似文献
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C. F. POETS A. ARNING W. BERNHARD C. ACEVEDO & H. VON DER HARDT 《European journal of clinical investigation》1997,27(4):293-298
Alveolar surfactant is well known for its ability to reduce minimal surface tension at the alveolar air–liquid interface to values below 5 mN m?1. In addition, it has been suggested that surfactant is also present in the airways, particularly in the perinatal period. We isolated surfactant from pharyngeal aspirates obtained from 33 neonates immediately after delivery and analysed it for both phospholipid (PL) composition and surface tension function. PL classes and phosphatidylcholine (PC) molecular species were determined by normal and reversed-phase high-performance liquid chromatography (HPLC), respectively. Static and dynamic surface properties of the surfactant were studied in a pulsating bubble surfactometer. Sample volume was 1.3 ± 0.5 mL (mean ± SD) with a total amount of 2.5 ± 1.3 μmol of PL and a concentration of 2.1 ± 1.0 μmol mL?1 PL. HPLC analyses of PL classes revealed a composition identical with surfactant prepared from alveolar washes, i.e. PC 83.6 ± 2.1%, sphingomyelin 1.4 ± 0.5%, phosphatidylglycerol 8.1 ± 1.6%, phosphatidylethanolamine 2.1 ± 0.5% and phosphatidylinositol 2.6 ± 1.1%. Thin-layer chromatography showed almost identical results but was more time-consuming and needed more material for analysis. Analysis of PC molecular species revealed a composition typical of human alveolar surfactant with 54.7 ± 3.9% dipalmitoyl PC, 10.3 ± 1.9% palmitoyloleoyl PC and 9.1 ± 1.5% palmitoylmyristoyl PC. Minimal surface tension fell to values below 5 mN m?1 within 5 min of cycling in all subjects. The methods used in this study allowed for complete PL and surface tension analyses of surfactant obtained during routine pharyngeal suctioning after delivery at term. Whether they are also applicable to preterm neonates with respiratory distress remains to be determined. 相似文献
95.
Kathleen M. Giacomini 《Journal of pharmacokinetics and pharmacodynamics》1997,25(6):731-741
Many clinically used drugs and their metabolites as well as a variety of environmental toxins are organic cations at physiologic pH. Secretion in the renal proximal tubule constitutes a major pathway in the elimination of organic cations. In this report, the results of studies recently performed in this laboratory are presented. First, the molecular cloning of a novel splice variant of organic cation transporter from rat kidney (rOCTIA) is described. The functional characteristics of the transporter are discussed along with the implications of RNA splicing in enhancing transporter diversity. Second, the molecular cloning of the first human organic cation transporter (hOCTI) is described. Distinct interspecies differences in the tissue distribution and function of this transporter is presented. These studies have paved the way for elucidating molecular structure function relationships of organic cation transporters and for determining their physiologic role in drug absorption and elimination. The cloned transporters can be used in mammalian expression systems for screening candidate compounds identified during drug discovery and development and in the in vivo prediction of the pharmacokinetics of therapeutic agents. 相似文献
96.
Clinical and diagnostic DNA laboratories must maintain a large inventory of DNA probes for use in hybridization studies. The preparation of plasmid DNA and isolation of DNA fragments for use as probes in both expensive and time consuming. We present here a rapid and relatively inexpensive method of producing large amounts of DNA fragments from stocks, using the polymerase chain reaction (PCR). Our experience over the past year using this technique has been very positive and we believe many laboratories could benefit by employing such a labor-saving approach to maintaining DNA probes. The technique uses the bacteriophage M13 DNA sequencing primers to amplify cloned inserts contained in commonly used plasmid vectors. As examples, we illustrate the use of DNA produced in this manner as probes for linkage analysis of the fragile X syndrome and for detection of deletions in the Duchenne muscular dystrophy gene. We have also found that at least two probes can be amplified in the same PCR reaction, allowing the detection of two different restriction fragment length polymorphisms (RFLP) simultaneously. It should be possible for laboratories to devise strategies particular to their individual needs using more than one DNA probe produced in the same PCR reaction to detect RFLP's. Such strategies would need only to consider that the predicted alleles of the multiple polymorphisms do not migrate to the same position during electrophoresis. Stocks of single or multiple probes produced by the PCR could then be maintained for more rapid Southern analyses. 相似文献
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Yasuo Aoki Souji Maruo Akira Arakawa Sadao Sasaki Seiki Hori 《Journal of orthopaedic science》1997,2(6):434-441
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed
demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine
iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity.
Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration
in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings
suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently
caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers.
On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached
the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations
in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes
may also play an important role in damage to nerve fibers. 相似文献
100.
研究煤焦油组分时,为了防止组分相互之间的干扰,在测定前用几种不同极性的溶剂:石油醚;80%石油醚-20%甲苯;60%石油醚-40%甲苯;40%石滑醚-60%甲苯;20%石油醚-80%甲苯;甲苯;氯仿;50%氟仿-50%甲醇;甲醇进行洗提,从煤焦油中得到9个级分。然后用荧光法从9个级分中鉴定出28个组分:茶、苊、联苯、三甲基酚、菲、异喹啉、芴、对氨基酚、联苯胺、蒽醌、四氢萘、2,5-二甲酚、蒽、咔唑、间苯二酚、二乙基苯胺、喹啉、吲哚醌、1,3,5-三甲苯、1,2,4-三甲苯、萘醌、菲醌、窟、苾、氧芴、1,2-苯并蒽、2,3-苯并蒽、3,4-苯并苾。同时定量了氯仿和甲醇级分中氧芴、(艹屈)、联苯胺、苾、菲、蒽、咔唑、四氢蔡咔、四氢萘、苯醌、喹啉、8-羟基喹啉等12个组分的含量。 相似文献