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11.
中国人血管抑素基因的克隆及其序列分析   总被引:1,自引:0,他引:1  
目的:克隆中国人血管抑素(angiostatin,ANG)基因全长并进行序列分析。方法:应用RT-PCR,将5例健康人肝脏组织ANG基因克隆到pSP71载体上,用Sanger法进行基因测序分析。结果:通过RT-PCR获得一个1141bp的扩增产物,测序发现与已报道的ANG比较,国人ANG上有3个碱基突变位点:分别为第825位C→T;第927位T→G和第1078位G→A。前两个碱基突变氨基酸未发生变化,第3个碱基突变结果使缬氨酸(Val342)改变成为蛋氨酸(Met342)。结论:克隆得到中国人ANG基因片段,其碱基和氨基酸的变化可能是人群中该基因的遗传多态现象。  相似文献   
12.
胃癌组织中核基质蛋白的变化   总被引:1,自引:1,他引:0  
目的:研究胃癌组织核基质蛋白的改变。方法:应用SDS-PAGE技术及Geneools定量分析软件,对22例胃癌组织及正常组织的核心基质蛋白进行了研究,结果:胃癌组织与正常组织比较,Mr为30000,28000的核基质蛋白表达量明显减少(P<0.05),不同分化类型及不同临床分期胃癌组织间比较,此种核基质蛋白表达量差异无统计学意义(P>0.05),结论:胃癌组织中核基质蛋白的改变可能在肿瘤的早期已经发生,是胃癌发生的早期分子事件。  相似文献   
13.
The effect of a carbon dioxide (CO2) pneumoperitoneum and its duration on rabbit follicular oocytes was assessed by evaluating fertilization and subsequent embryonic development rates. CO2 may cross the plasma membrane and form carbonic acid, which liberates H+, thus lowering the intracellular pH. There were no significant differences in arterial pH and [HCO3-] between CO2 and air treatment groups, whereas arterial pCO2 and pO2 were significantly increased in the CO2 treatment group. We found that the duration of pneumoperitoneum, irrespective of type of gas used, was negatively correlated with success of embryonic development. These findings necessitate that more attention be given to the gas used for creation of a pneumoperitoneum during egg retrieval for in vitro fertilization and an attempt be made to minimize duration of the pneumoperitoneum.  相似文献   
14.
目的:构建含有目的基因kring5的真核植物细胞穿酸表达载体。方法:应用RT-PCR方法,从正常人肝脏组织中获得kringle5基因,测序后,再通过DNA重组技术,将kringle5基因片段克隆到真核植物细胞表达载体pBI121和pCAMBIA3301上。结果:得到的kringle5基因序列测定结果与文献相符,重组载体pB1k5和pC33k5经酶切鉴定正确,含有植物高效表达CaMV35S启动子。结论:重组载体pB1k5和pC33k5不仅可以在大肠杆菌中稳定复制,而且可以在植物细胞中表达。  相似文献   
15.
采用已报道的金黄色葡萄球菌质粒DNA的检测方法(简称LL法)。从1982年在南京地区临床分离的131株金黄色葡萄球菌中的125株(95.4%)中检出质粒,可分为21质粒谱。经单向及双向二步琼脂糖凝胶电泳法鉴别,按分子量共有16个CCC型质粒带(P_1~P_(16))。用改良的LL法制备E.coli V517菌株质粒DNA,建立了简便的测定金黄色葡萄球菌质粒DNA分子量的参考系统。结果表明:要本实验条件下,P_1~P_(16)的分子量为1.42 Md~22.24±0.73 Md;以含有14.88、2.66±0.06 Md质粒谱的菌株较常见,占总数的25.2%;2.66±0.06 Md的质粒最常见,在73.3%的菌株中检出。  相似文献   
16.
The growth of bioscience knowledge over the last two decades has increased the potential benefits of scientifically based patient care by contributing to the theory of clinical care. However, there is little evidence that knowledge, derived from the human biosciences is being fully incorporated into nursing theory and practice.Nursing has developed its own unique professional body of knowledge, heavily influenced by behavioural science. If nursing theory leans towards behavioural science, but practice is devoted to problems of biological disturbance, nursing may be facing a widening theory-practice gap, greater than other professions. The theory-practice gap in nursing may be widened by the exclusion of bioscience from nursing theory. Nurses' relative disinterest in the natural sciences can be attributed both to sociological reasons and to problems stemming from the symbol-object dichotomy that recur in the teaching of natural sciences. Reflection on practice and examination of education method are suggested as strategies for re-introducing bioscience into nursing theory and practice. A challenge facing nurse educators is the integration of biological science into the nurses' conceptual ecologies. For, if nursing fails to make bioscience its own, much of the clinical welfare of patients will become a medical monopoly.  相似文献   
17.
The role of the gubernaculum during testicular descent was investigated in 115 male pig fetuses ranging from 68 to 109 days of gestation. Descent of the testis through the inguinal canal occurred between 77 and 94 days. There was a marked increase in the total and relative wet mass as well as the wet/dry mass ratio of the gubernaculum, denoting an increase in the water content of this structure during descent of the testis. Similar changes were not seen in other fetal tissues. Asymmetrical descent of the testes occurred in seven of the 40 fetuses between 81 and 92 days of gestation. Descended testes had gubernacula with a greater relative wet mass than the gubernacula of undescended testes. These findings indicate that the increase in mass of the gubernaculum plays an important part in testicular descent. An increase in both the DNA content (hyperplasia) and the RNA/DNA ratio (hypertrophy) was noted in the gubernaculum during descent of the testis. Hyperplasia in the gubernaculum occurred at a rapid rate initially and ceased after the completion of descent. Hyperplasia was also seen in the testis and epididymis, but occurred at a slower rate initially, with a rapid acceleration after the completion of descent. Cellular hypertrophy was not noted in the testis and epididymis, but did occur in umbilical cord tissue. If gonadotropins acting via androgen secretion by the testis provide the stimulus for these changes, the observed difference in response between the gubernaculum and testis could be due to a difference in end-organ sensitivity. However, it is also possible that some unidentified non-androgenic gubernaculotropin, possibly secreted by the fetal testis, provides the stimulus for gubernacular growth.  相似文献   
18.
恶性肿瘤是威胁人类生存的第一杀手,就头颈肿瘤来说虽然发病率在我国并不高,但由于我国人口众多,发病率的绝对数字也是不可忽视的。当今提倡晚期头颈肿瘤的综合序列治疗,患者的生存率及生存质量已有很大的提高,由于我国的地域差异和医学发展水平的不平衡,对于头颈肿瘤的治疗难以形成统一的治疗标准,目前国内也缺少头颈肿瘤的诊断治疗指南,客观存在着肿瘤的诊断治疗欠规范,延误诊治、过度治疗、治疗不够等现状,这不仅导致医疗资源的浪费和国家及个人的经济负担加重,而且由此导致的医患纠纷时有发生。鉴于此,本期刊出由上海交通大学医学院附属第九人民医院·口腔医学院郭伟等医师编译的2005年美国国立癌症综合信息网(National Comprehensive Cancer Network,NCCN)公布的由NCCN头颈肿瘤专家组31位专家撰写的关于头颈部恶性肿瘤诊断治疗指南的有关内容,旨在结合我国实际情况供专业人员参考。  相似文献   
19.
PURPOSE: To describe a radiographic finding--enhancement of the cisternal portion of the third cranial nerve on postcontrast MR--and to correlate it with patients' clinical symptoms and ultimate diagnosis. MATERIALS AND METHODS: Thirteen consecutive patients with enhancement of the cisternal portion of the third cranial nerve on postcontrast MR were retrospectively identified; 50 control patients referred for pituitary microadenomas were also retrospectively reviewed. FINDINGS: The enhancement was bilateral in six patients and unilateral in seven patients. Four of the six patients with bilateral enhancement had unilateral oculomotor nerve palsies; none had bilateral third cranial nerve palsy. Five of the seven patients with unilateral enhancement had ipsilateral third nerve palsies. Of the nine patients with third nerve palsies, the pupil was involved in four patients. Follow-up studies were available in six patients, four of whom had third nerve palsy. Resolution of the enhancement correlated with resolution of the symptoms in two patients. The patients' underlying diagnoses were lymphoma (four), leukemia (one), viral meningitis (one), neurofibromatosis (two), inflammatory polyneuropathy-HIV related (one), ophthalmoplegic migraine (one), Tolosa-Hunt syndrome (one), coccidioidomycosis (one), and diabetes (one). No enhancement was seen in any of the controls. CONCLUSION: Enhancement of the cisternal segment of the third cranial nerve is always abnormal, revealing an underlying inflammatory or neoplastic process. However, it is not always associated with clinically apparent oculomotor nerve dysfunction.  相似文献   
20.
BACKGROUND AND PURPOSE: Waiting lists for radiotherapy have become longer over the past years. Apart from the psychological distress for the patient we are concerned about tumour growth during this waiting time, which may worsen prognosis. The purpose of this pilot study was to investigate tumour growth in the waiting time and to obtain an indication of its clinical consequences for patients with oropharyngeal carcinoma. A tumour control probability (TCP) model was applied to evaluate consequences for outcome. METHODS AND MATERIALS: Increase in tumour volume was measured for 13 patients with oropharyngeal carcinoma by outlining the tumour on the diagnostic as well as on the treatment planning CT scan. Waiting time was defined as time between histopathological diagnosis and start of radiotherapy. For each tumour we calculated the increase in tumour volume and the tumour doubling time. The potential increase in TCP was calculated for each tumour for the situation without treatment delay. RESULTS: The mean increase in tumour volume was 70%. The mean waiting time was 56 days. Expected TCP with incorporation of delay was 47%, without delay it might have been 63-66%. CONCLUSION: This study shows tumour progression during the time between the diagnostic CT scan and the treatment planning CT scan in oropharyngeal cancer. As a consequence of waiting time, which allows tumour volume increase, there may be an average control loss of 16-19 % for these tumours during the total waiting time before radiotherapy.  相似文献   
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