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11.
藏汉民族线粒体基因组全序列的比较研究   总被引:1,自引:0,他引:1  
目的 以藏汉民族线粒体基因组全序列为基础,进行Haplogroup构建和系统发生分析,在全序列水平上比较核苷酸的变异,阐释可能的变异机制和蕴含的生物学意义.方法 采用Applied Biosystems 3730DNA自动测序仪分别对40名藏族和50名汉族的标本进行线粒体DNA序列测定,应用phredPhrap 16.0软件进行全序列拼接,并以rCRS(revised Cambridge Reference Sequence)为标准与测定序列进行比对分析;根据MTTO-MAP的标准,通过Network方法进行Haplogroup构建和系统发生的分析,并结合其它方法对产生的数据进行深入解读.结果 数据分析结果显示:在系统发生上,藏汉民族90个线粒体DNA序列归类到13个Haplogroups,除M9以外,其它各Haplogroup出现频率之间比较差异无统计学意义;通过两个民族的线粒体DNA全序列比对,发现21个分布频率有统计学意义的变异位点,其中的5个为新变异位点;另外,对D-Loop区的5个突变位点进行了单倍型构建,90个标本可分为2种Supertype,发现在藏汉民族之间Supertypel和Supertype 2的分布频率均有统计学意义.结论 藏汉民族在种族起源和系统发生上具有较近的母系遗传关系;在全序列有统计学意义的位点究竟是适应性或者中性选择,抑或是一种病理性突变尚需深入的探讨.  相似文献   
12.
The kidneys are vital organs in the management of fluid balance, waste product removal, electrolyte homeostasis, acid–base balance and endocrine function. Waste products removed by the kidney are urea, uric acid and creatinine; other foreign products with similar physiochemical properties are also excreted. Urea and uric acid are by products of protein metabolism and creatinine is generated by the metabolism of creatine compounds from muscle. The kidney regulates fluid and electrolyte balance through controlling the composition and volume of urine. In the proximal convoluted tubule and the loop of Henle, 90% of sodium, potassium, calcium and magnesium are reabsorbed. Acid–base balance is achieved by regulating the excretion of hydrogen ions and bicarbonate buffering. The kidney also has a number of endocrine functions including the production of renin and erythropoietin as well as hydroxylation of vitamin D. The kidneys receive 25% of cardiac output, generating 170–200 litres of ultrafiltrate per day. Urine output is approximately 1.5 litres per day, which is concentrated ultrafiltrate through selective reabsorption of solutes and water. In this article we will discuss tests frequently used to assess renal function.  相似文献   
13.
Journal of Community Health - The purpose of this study was to evaluate family physicians’ job strain during the Covid-19 pandemic and determine the effective factors. The study was carried...  相似文献   
14.
A rare case of hydatid cyst of the pancreas is reported. Although ultrasonography and computerised tomography scan confirmed the presence of a cystic mass in the body and tail of the pancreas, diagnosis was made only on laparotomy. A distal pancreatectomy was done and the diagnosis of hydatid cyst of the pancreas was confirmed by histopathology. Though very rare, pancreatic hydatidosis should be considered in the differential diagnosis of cystic lesions of the pancreas in the appropriate epidemiological setting.  相似文献   
15.
We report a unique case of a patient who underwent cystectomy with ileal conduit for nonmalignant bladder disease. Patient postoperatively developed stomal necrosis which was managed conservatively but after few months there was severe stomal stenosis and retraction and patient ended up with bilateral nephrostomies. On planned open abdominal exploration with intention to refashion stoma, after resection of distal stenosed segment we found that it was impossible to mobilize proximal portion of conduit due to severe small bowel adhesions. We used a unique approach of creating one more ileal conduit, bringing it as a new stoma on one side and anastomosing its other side with proximal one (ileal conduit over conduit) to augment deficient portion. This technique is not mentioned in the literature and as such we are reporting same as it can help many urologists who may encounter such problems.  相似文献   
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17.
A new species of spirochete which we have called Spirochæta hebdomadis has been described as the specific etiological agent of seven day fever, a disease prevailing in the autumn in Fukuoka and other parts of Japan. This spirochete is distinguishable from Spirochæta icterohæmorrhagiæ to which it presents certain similarities. Young guinea pigs are susceptible to inoculation with the blood of patients and to pure cultures of the spirochete, and those developing infection exhibit definite symptoms suggestive of those of seven day fever in man. The blood serum of convalescents from seven day fever contains specific immune bodies acting spirochetolytically and spirocheticidally against the specific spirochetes, but not against Spirochæta icterohæmorrhagiæ. The field mouse (Microtus montebelli) is the normal host of the spirochetes, which have been detected in the kidneys and urine of 3.3 per cent of the animals examined. The endemic area of prevalence of seven day fever corresponds with the region in which field mice abound.  相似文献   
18.
Horses immunized with cultures of Spirochæta icterohæmorrhagiæ yield an immune serum having therapeutic properties. With rare exceptions the serum destroys completely the spirochetes contained in the circulating blood. The development of antibodies is promoted by the serum injections. The number of spirochetes in the organs is reduced by the treatment. Secondary manifestations due to the serum are slight and disappear promptly. The ultimate effects of the serum treatment on the symptoms and final outcome of the disease have still to be determined.  相似文献   
19.
目的通过系统的生物信息学分析和实验验证,筛选黄热病毒的特异抗原片段,为免疫诊断试剂的研制奠定基础。方法分别利用DNAStar及ANTHEPROT软件对黄热病毒蛋白进行分析,参考亲水性、抗原性、可塑性、表面可及性及二级结构信息,对黄热病毒可能的共有及特异性抗原表位进行系统的预测分析,分析其在不同毒株中的保守性,并对预测得分值较高的抗原区域进行RT-PCR扩增,利用pMal-c2x原核表达系统进行原核表达,Western blot验证其免疫学反应原性,检测阳性抗原片段经亲和纯化后,包被ELISA微孔板,进一步验证其免疫学反应特异性及检测敏感性。结果其中27段抗原片段获高效表达,经Western blot筛选及ELISA进一步验证,原核表达抗原片段YFV22表现良好特异抗,可检测低至1∶12 800倍稀释的黄热病毒多克隆抗体,与所试其他参考病毒多克隆抗体无交叉反应。结论经系统筛选、验证,获黄热病毒特异性抗原片段1段,为其免疫学诊断试剂的研制奠定了基础。  相似文献   
20.
目的:采用HPLC法测定四川粉葛中葛根素的含量。方法:色谱柱为依利特C18柱(4.6min&;#215;150mm,5μm),流动相为甲醇-水(25:75),流速为0.8ml/min,检测波长为250nm,柱温为25℃。结果:葛根素在0.0880~0.7040μg范围内峰面积与进样量呈良好的线性关系,回归方程为A=336.35X-1.7716,r=1.0000,其平均同收率为100.01%,RSD为0.14%(n=6)。结论:该方法简便易行,结果准确,可用于四川粉葛药材的质量控制。  相似文献   
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