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1.
超市连锁店熟食卤味销售的HACCP研究   总被引:2,自引:0,他引:2  
应用HACCP的原理和方法,对超市连锁店熟食卤味销售进行了危害因素分析,找出了关键控制点(CCP),提出了控制措施,并建议超市连锁店销售非包装熟食卤味时使用密封低温冷藏展示柜。  相似文献   
2.
We have identified the A3243G heteroplasmic point mutation in mitochondrial DNA from a female patient with headache as the main clinical feature. The mitochondrial origin of her disease was only suspected because of her brother with MELAS syndrome. Morphological and biochemical studies failed to reveal mitochondrial respiratory chain dysfunction in her muscle which contained 65% of mutated mitochondrial DNA molecules. Molecular studies performed among four generations (in the blood of seven subjects) showed the variable transmission of mutated molecules and pointed out the difficulty in giving genetic counsel.  相似文献   
3.
Molecular genetic analysis was performed in a patient with cytochrome b positive X-linked chronic granulomatous disease. A previous Southern blot study, using a cytochrome b heavy chain cDNA as probe, revealed a Pst I restriction fragment pattern for the cytochrome b heavy chain gene (CYBB) different to that of normal individuals. Since restriction length polymorphism with Pst I has never been observed in control individuals and no abnormal restriction fragment patterns in the patient's CYBB was detected with seven other enzymes used, we focussed on the single Pst I site in the CYBB cDNA as being the only mutation site responsible for his disease. A fragment of the patient's cDNA which included the Pst I site was amplified by reverse polymerase chain reaction, and loss of the Pst I site in the fragment was confirmed by incubation with Pst I. Subsequent sequence analysis of the fragment revealed a point mutation in the Pst I site (cytosine to adenine), substituting glutamic acid for alanine at position 57.  相似文献   
4.
目的:探讨GPC4基因与中国山东Smith-Fineman-Myers综合征(SFMS)的关系,并分析SFMS患者GPC4基因突变。方法:利用primer3设计扩增GPC4全部编码序列及内含子和外显子接头序列的引物,采用PCR扩增结合PCR产物直接测序方法检测GPC4基因开放性阅读框架区域基因突变。结果:在GPC4基因开放性阅读框架区域内并未检测到导致疾病的基因突变。结论:山东SFMS家系患者不是由于GPC4基因编码区域基因突变所致。  相似文献   
5.
毛细管电泳技术快速检测p53基因点突变   总被引:1,自引:0,他引:1  
目的:探讨利用毛细管电泳技术快速检测p53基因点突变的临床应用价值。方法:采用毛细管电泳作SSCP分析,检测20例结肠癌肿瘤标本p53基因第7外显子PCR扩增产物,并与传统的聚丙烯酰胺凝胶电泳结果进行比较,最后用DNA序列测定判断其准确性。结果:20例结肠癌标本中,毛细管电泳技术检测出5例标本(Ca4,Ca6,Ca7,Ca8,Ca14)有突变,而凝胶电泳结合银染技术仅检出4例标本(Ca4,Ca6,Ca7,Cal4)有突变,测序证实经毛细管电泳所检出的5例标本均存在点突变。结论:对于PCR产物的单链构象多态性分析,毛细管电泳技术是一种更加快速、简便、敏感的方法,可应用于临床筛查基因点突变。  相似文献   
6.
The allele-specific PCR approach has been modified by introducing a second mismatch at the 3'-penultimate link of the primer and used to identify the sickle cell anemia mutation (A-->T transversion in the sixth codon of the human beta-globin gene causing Glu-->Val substitution in the protein), thus obviating the problem of an interpretationally ambiguous 3'-terminal mismatch including T residue.  相似文献   
7.
Familial amyloidosis, Finnish type (FAF) (gelsolin-related amyloidosis) is an autosomal dominant form of systemic amyloidosis characterized by corneal lattice dystrophy and peripheral polyneuropathy. The accumulating protein in FAF consists of fragments of gelsolin, an actin-modulating protein. The gelsolin mutation G654A has been found in both Finnish and Japanese patients. To study the origin of the gelsolin mutation in these patients we performed haplotype analysis in 10 Finnish and 2 Japanese FAF families. Poymorphic DNA markers GSN, D9S103, AFMa061xd9, and AFMa139xb9 revealed a uniform disease haplotype in all the disease-associated chromosomes of the Finnish FAF families, which was different from the one observed in the Japanese families. The present results and the previously detected gelsolin mutation G654T in Czech and Danish FAF patients suggest that nucle otide 654 may represent a mutation hot spot in the gelsolin gene. The DNA markers studied here will be useful in future genealogical analyses of FAF. © 1995 Wiley-Liss, Inc.  相似文献   
8.
作者用“点值法”对成都市内和郊区842例从事轻、中、重劳动的健康工人、农民和战士作了MEFV曲线和常规肺功能测定,发现工人和农民在低肺容积时流量增加,在高、中肺容积时流量下降,并以农民最明显,重劳动工人次之,轻、中劳动工人较不明显,战士则相反。揭示不同的体力活动方式及生活条件可导致不同肺容积时的流量改变,以适应其代谢增强时的耗氧需求。  相似文献   
9.
Risk stratification is of utmost importance in burn therapy. However, suitable bedside biomarkers to evaluate the emerging inflammatory response following burn injuries are missing. Serum cholinesterase (butyrylcholinesterase, BChE) has been shown to be a clinically relevant biomarker in acute inflammatory diseases including burns.In this observational cohort study BChE activity was measured by using point-of-care testing (POCT), a novel method in acute burn care. POCT measurements were performed at emergency room admission (ERA) of 35 patients and repeated 12, 24 and 48 h later. All patients or their legal designees gave informed consent.Patients with burn injuries showed sustained BChE activity reduction following hospital admission. BChE activity correlated negatively with burn injury severity, organ failure severity and intensive care unit resource requirements. BChE activity measured at ERA and 12 h later identified survivors and predicted 28-day patient outcome with noninferior efficacy compared to the abbreviated burn severity index (ABSI) scoring. Finally, POCT-measured BChE activity might complement ABSI scoring and possibly improve early risk stratification in acute burn care therapy.  相似文献   
10.
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