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981.
薄层色谱紫外分光光度法定量测定微生物发酵产物辅酶Q10 总被引:1,自引:0,他引:1
报道了一种微生物发酵液中辅酶Q10的定量检测方法.该方法分为两个步骤:第一步是离心收集菌体和结合使用超声波处理的辅酶Q10丙酮抽提;第二步是硅胶薄层色谱,根据标样位置取产物斑点乙醇洗脱后用紫外分光光度法测定辅酶Q10含量.结果表明,该方法具有操作简便、重复性好、相对误差小等优点,可用于细菌发酵生产辅酶Q10研究过程中发酵产物的快速定量检测.图2表2参6 相似文献
982.
Young-Mi Kim Eun-Hee Cho Jin-Mi Kim Moon-Hee Lee So-Yeon Park Hyun-Mee Ryu 《黑龙江环境通报》2004,24(3):161-164
We report a de novo translocation between chromosome 15 and 18 resulting in monosomy 18p in prenatal diagnosis. The patient was referred for amniocentesis due to increased nuchal translucency (INT) (5 mm) at 13.6 weeks of gestation. Karyotype of the fetus revealed 45,XX,der(15;18)(q10;q10) in all metaphases. The targeted fetal ultrasound at 20 weeks of gestation did not show any special physical abnormalities other than 6.4 mm of nuchal fold thickness. Molecular cytogenetic findings using CGH and FISH confirmed the del(18p) with dicentromeres from both chromosome 15 and 18. The present study shows that the INT at first trimester was the only prenatal finding for the fetus with del(18p) syndrome and that molecular cytogenetic methods are useful for detecting chromosomal aberrations precisely. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
983.
984.
A rare complication of twin-to-twin transfusion syndrome (TTTS) is described: myocardial infarction of the recipient fetus. Myocardial infarction and hydrops are considered to be consequences of hypertension in the recipient. No other organs were affected. Pathological signs of intrauterine hypertension were estimated by the thickness of vessel walls and signs of hypertrophied myocardial cells. In the heart of the recipient fetus there was a chronic myocardial infarction near the apex cordis on the anterior wall with an aneurysm 4×5 mm in diameter. Diagnosis was based on light microscopic examination. The poor myocardial systolic function resulted in hydrops. Since the mother was administered β sympathomimetics in therapeutic doses the contribution of the drug to the myocardial infarction is uncertain, but we would like to suggest this as a possible adverse effect in TTTS. The present case is the first reported myocardial infarction in connection with the syndrome. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
985.
986.
Preimplantation genetic diagnosis (PGD) was developed more than a decade ago to offer an alternative to prenatal diagnosis for couples at risk of transmitting an inherited disease to their offspring. Portuguese-type familial amyloidotic polyneuropathy (FAP type I), is an autosomal dominant disease presenting an inherited mutation in the gene encoding the plasma protein transthyretin (TTR). We here report the first protocol for single-cell detection of the Met30 mutation in FAP type I and its application to PGD. A nested PCR reaction for exon 2 of the TTR gene was developed. The PCR product was then analysed by restriction enzyme analysis and SSCP allowing the detection of the point mutation. Ten clinical cycles were performed in seven couples. From the 93 metaphase II (MII) injected oocytes, 82 were normally fertilized and 78 were biopsied. A positive signal in the nested PCR reaction was obtained in 61 blastomeres, corresponding to a DNA amplification efficiency of 78.2%. No allele dropout (ADO) or contamination were detected. A biochemical pregnancy was obtained in three cases and a clinical pregnancy in one couple is actually in normal evolution. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
987.
基于高程的环境库兹涅茨曲线实证分析 总被引:2,自引:0,他引:2
本文利用GIS的空间分析技术。以高程带为取样单元。研究在高程带上三种主要的大气污染物与经济发展之间的定量关系。以重庆市为例,验证环境库兹涅茨在高程上是否存在。研究结果发现。污染物浓度随高程的增加呈非单调下降的趋势。人均GDP随高程的增加先增大后减小。在高程上。污染物浓度与经济发展之间的关系和两者在时间序列和国别(或地区)序列上环境库兹涅茨曲线研究的结论相似。其中。TSP和NOx分别与人均GDP之间呈较稳定的呈“N”形和饲“U”形关系。受人口密度和高程影响较大;而SO2与人均GDP之间关系不稳定。 相似文献
988.
We present a case report on a fetus with multiple malformations, diagnosed by ultrasound at 20 weeks' gestation. From the combination of intrauterine growth retardation and limb abnormalities that were observed, the most likely diagnosis was considered to be Cornelia de Lange Syndrome (CdLS). Following counselling, the mother opted to terminate the pregnancy. Chromosome analysis of cultured amniotic fluid cells showed a karyotype of 46,XX,t(3;5)(q21;p13). Postmortem examination of the baby confirmed the presence of features consistent with a diagnosis of CdLS. This case provides a report of a definitive diagnosis of Cornelia de Lange Syndrome, suspected on the basis of ultrasound imaging and confirmed by amniocentesis findings. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
989.
990.