基因定量检测方法研究进展

基因定量检测已经成为研究基因组变异以及由于基因重组所引起的相关疾病的重要手段。大片段的基因组的重复和缺失可以引起致病突变。使用PCR和测序等定性检测方法很难探测到杂合状态的缺失和重复,因此探寻高效、可靠、灵敏的基因定量检测方法是当务之急。在过去的几年中已经相继出现了一些自动高效的技术方法。现在可用的基因定量方法大致可以分成3类:DNA印迹技术,细胞遗传学方法和以PCR扩增为基础的定量。本文对基因定量的最新进展作一综述,探讨其优缺点以期对定量研究方法的选择有所帮助。     

The usefulness of CEA as an indicator for early detection and a guide to the treatment of recurrent gastric cancer

The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25 of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression. Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis (68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results.     

血清TPS浓度在消化道肿瘤中价值的研究

共选择３０例消化道肿瘤病人，其中食管癌，胃癌，大肠癌各１０例，设健康献血者３０例，对两组血清特异型组织多肽抗原浓度进行了检测，结果肿瘤组血清ＴＰＳ浓度明显高于健康人。消化道肿瘤阳性检出经达７０％，其中食管癌８０％，胃癌６０％，大肠癌７０％。消化道肿瘤合并淋巴转移阳性检出率达７６．９％，其中食管癌１００％，胃癌６６．７％，大肠癌７０．０％。随着病程发展，血清ＴＰＳ浓度呈现升高趋势。     

脉动真空灭菌器内室气体流向监测报警装置的研制

本文针对XGI型脉动真空灭菌柜出现的蒸汽倒流故障设计出一种内室气体流向监测报警装置，对管道中的蒸汽流向和空气流向进行监测。当出现倒流现象时，报警装置发出报警信号，提醒工作人员采取措施排除故障。经在两台灭菌柜上使用，证明此方案是一种行之有效的方法。     

Dopamine receptor agonists alter gap prestimulus modulation

An innocuous sensory event (a prestimulus) that briefly precedes a startle-eliciting stimulus (SES) will reduce the amplitude of the subsequently elicited reflex. In three experiments brief silent periods in otherwise continuous noise (gaps) were used as prestimuli to investigate the effects of the D₁ dopamine receptor agonist (±)-SKF-38393 (SKF) and the dopamine D₂ receptor group agonist (−)-quinpirole hydrochloride on gap inhibition of the rat’s acoustic startle reflex. Gap durations of 4 and 50 ms were analyzed. Quinpirole (0–1.6 mg/kg) had a biphasic effect on gap inhibition. Lower doses increased gap inhibition, an effect that peaked at the 0.4 mg/kg dose. For higher doses, inhibition returned to control levels for the 4-ms long gap, but remained elevated for the 50-ms long gap. SKF had no effect on gap inhibition, and haloperidol (0.2 mg/kg) reversed the quinpirole-induced increase of gap inhibition. These data implicate the D₂ dopamine receptor group in gap inhibition of startle modulation. The results are discussed in terms of the effects of catecholamine agonists on attention. Received: 25 July 1995/Final version: 28 April 1997     

Indirect detection of anti-acetylcholinesterase compounds in microcolumn liquid chromatography using packed bed reactor with immobilized human red blood cell acetylcholinesterase and choline oxidase

The inhibiting compounds were separated by micro-column liquid chromatography in the mobile phase containing the natural substrate acetylcholine. A home-made packed bed microbioreactor system containing immobilized enzyme acetylcholinesterase (ACHE) in human red blood cell membrane and choline oxidase (CHO) from alcaligenes was used for the post-column conversion of acetylcholine to hydrogen peroxide which was detected by an electrochemical detector. The inhibition effect of the solutes caused a decrease in the acetylcholinesterase activity, a decrease in the formation of hydrogen peroxide and also a decrease in the response corresponding to the concentration of the solutes. The rate of the enzyme regeneration was also recorded. The micro-system was compared with a conventional LC system comprising commercially prepared enzyme reactor. The stability of the enzymes is at least 3 weeks at ambient temperature. The limit of detection depends on biological activity of inhibition and for galanthamine was 1 pmol.     

转基因食品的快速PCR鉴定

用十六烷基-二甲基-乙基-溴化铵(CTAB)法快速高效地从样品中提取了可供分析的基因组DNA,经PCR扩增,鉴定了含有35S启动子和NOS终止子的转基因样品.该方法的灵敏度可达0.1%,并且具有很好的稳定性.     

应用数据挖掘技术获取周围型肺癌临床和CT诊断规则的初步研究

目的探讨数据挖掘技术对周围型肺癌影像诊断规则提取的价值。方法收集58例经过临床病理证实的周围型肺癌病例,对其临床及CT表现属性进行标准化认定,输入数据库,分别采用自主开发的基于关联规则知识发现程序与通用数据分析工具ROSETTA中的粗糙集约简算法和遗传分类算法对58例周围型肺癌临床及影像学数据进行挖掘对比研究。结果由Johnson’s Algorithm粗糙集约简算法产生诊断规则51条,由ROSETTA遗传分类算法所产生的诊断规则有5千多条,基于关联规则的挖掘算法所产生的诊断规则有123条。这3种不同的数据挖掘方法产生的最重要的诊断规则基本上都将性别、年龄、位置、毛刺、形状、毛玻璃样密度等属性作为诊断周围型肺癌的主要依据。结论数据挖掘技术在医学影像诊断和鉴别诊断中具有潜在的应用价值。     

Fine mapping of X-linked clasped thumb and mental retardation (MASA syndrome) in Xq28

The MASA syndrome is an X-linked disorder with mental retardation, spastic paraparesis, and adducted thumbs as the most characteristic features. We performed linkage analysis, using Xq28 markers, on a large MASA syndrome family. The maximum lodscore was 6.37 at 0 recombination for DXS52 and 5.99 at 0 recombination for DXS305. Crossovers were demonstrated between the disorder and DXS455. Clinical and linkage data from this family further support the hypothesis that the MASA syndrome and X-linked hydrocephalus are allelic disorders.