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The QT interval was measured in 12 normal and 7 aborted sudden infant death syndrome (SIDS) infants in rapid eye movement (REM) and quiet sleep at monthly intervals through the age of 4 months. An accuracy of better than 2 msec was assured by high resolution of the digitized signal and calibration of each QT measurement with an accurately generated time code. In contrast to current speculations, the QT index was significantly smaller in the infants with aborted SIDS than in the normal infants in both REM and quiet sleep (P less than 0.05). In addition, as in normal infants, the QTc was smaller in REM than in quiet sleep (P less than 0.01). Although these results offer no support for the hypothesis that SIDS results from prolongation of the QT interval, they suggest that aborted SIDS infants have a functional abnormality in the autonomic nervous system.  相似文献   
63.
泽泻提取物不同组分对尿草酸钙结石形成的实验研究   总被引:6,自引:0,他引:6  
目的 :研究泽泻提取物不同组分对尿草酸钙结石形成的影响 ,并确定其抑制尿草酸钙结石形成的有效部位。方法 :通过喂服泽泻提取物不同组分对乙二醇和氯化铵诱导的大白鼠肾草酸钙结石模型进行实验研究。结果 :服用泽泻醋酸乙酯浸膏的醋酸乙酯洗脱液大鼠的血清尿素氮 (BUN) ,肌酐 (Cr) ,肾钙 (Ca2+ )含量 ,24h尿Ca2+ 分泌量 ,肾组织的草酸钙晶体沉积均明显低于成石组 (P<0.05)。结论 :泽泻醋酸乙酯浸膏的醋酸乙酯洗脱液能抑制实验性高草酸尿症大白鼠体内肾草酸钙晶体的形成 ,是泽泻抑制尿草酸钙结石形成的有效部位。  相似文献   
64.
喉鳞状细胞癌组织体外原代培养的初步研究   总被引:1,自引:0,他引:1  
目的 应用体外培养技术,对喉鳞状细胞癌组织进行体外培养,探讨喉鳞癌组织原代培养中的各种影响因素,为建立人喉鳞癌组织的细胞系提供实验基础。方法采用体外组织培养技术,对24例人喉鳞状细胞癌组织进行原代培养,观察原代培养中肿瘤细胞的生长与供体的年龄、肿瘤组织的分化程度及不同培养方法的关系,分析在人喉鳞癌细胞的培养中成纤维细胞、微生物污染的影响。结果 24例人喉鳞状细胞癌组织标本,年龄小于60岁组的细胞生长率为31.25%(5/16例),年龄大于60岁组为37.5%(3/8例);高分化组为100%(2/2例),中分化组为30.8%(4/13例),低分化组25%(2/8例);组织块培养法为43.75%(7/16例),酶消化法培养为10%(1/10例);倒置显微镜下观察,在培养的第5~7天,在贴壁组织块周围可见到有上皮样细胞爬出。全部标本中,成纤维细胞的过度生长和微生物的污染是阻碍人喉鳞癌细胞生长的重要因素。结论培养组织的细胞生长率与供体的年龄关系不大;肿瘤组织的分化程度较高者,细胞的生长率较高;与酶消化分离培养法相比,贴壁组织块培养法的细胞生长率较高;成纤维细胞及微生物的污染是阻碍人喉鳞癌细胞系建立的重要因素。  相似文献   
65.
BACKGROUND: The purpose of this study was to evaluate the tolerance and efficacy of combining i.v. irinotecan, 5-fluorouracil (5-FU) and leucovorin (LV) with hepatic arterial infusion (HAI) of pirarubicin in non-resectable liver metastases from colorectal cancer. PATIENTS AND METHODS: Thirty-one patients were included in a phase II trial with i.v. irinotecan/5-FU/LV administered every 2 weeks, combined with HAI pirarubicin 60 mg/m(2) on day 1 every 4 weeks. In most cases HAI was administered via a percutaneous catheter. RESULTS: The main grade 3/4 toxicity was neutropenia, encountered in 78% of the patients. When all patients were considered in the analysis, tumour response rate was 15 out of 31 [48%; 95% confidence interval (CI) 32% to 65%]. Liver resection was made possible in 11 patients (35%; 95% CI 21% to 53%). There were no toxic death. Median overall survival was 20.5 months, and median progression-free survival was 9.1 months. In patients with completely resected metastases, median overall survival was not reached and median progression-free survival was 20.2 months. CONCLUSION: The multimodality approach used in the present study was well-tolerated and yielded dramatic responses. An aggressive approach combining i.v. and HAI chemotherapy deserves further investigation.  相似文献   
66.
γ射线对大鼠血管平滑肌细胞增殖和周期影响   总被引:2,自引:1,他引:2  
目的:探讨γ射线对大鼠血管平滑肌细胞(VSMCs)抑制作用机理。方法:对大鼠VSMCs进行原代培养,经^3H-TdR掺入法观察γ射线对VSMCs增殖情况影响,应用流式细胞仪检测γ射线对VSMCs细胞周期的影响。采用Western Blot技术检测γ射线对VSMCs p53、细胞周期素D(cyclin D)和增殖细胞核抗原(PCNA)表达的影响。结果:γ射线对寻殖的抑制作用呈剂量依赖性。γ射线照射可诱导VSMCs出现G1期阻滞,在照射后一定时间内会导致p53表达增强,cyclinD和PCNA表达减弱,结论:γ射线可抑制VSMCs增殖,其机制可能主要是γ射线诱导VSMCs出现G1期阻滞,抑制VSMCs进行有丝分裂,在这个过程中p53,cyclinD和PCNA等分子起到一定作用。  相似文献   
67.
Proteus syndrome     
Abstract: This female Asian (Malay) baby had clinical features of Proteus syndrome. She had a large right facial lipolymphangioma with hyperpigmentation of the overlying skin. There was a smaller lymphangioma over the left side of her neck with excess nuchal folds, macrodactyly and bilateral talipes equinovarus. Despite the extensive hemifacial swelling, there was no evidence of upper respiratory tract obstruction. Generalized seizures developed on the sixth day of life which were controlled with phenobarbital. The lymphangiomas were excised without recurrence.  相似文献   
68.
Objectives: A prospective study comparing the efficiacy and side-effects of oral sulindac with intravenous indomethacin in clinically stable preterm infants (<1750 g) requiring non-invasive closure of haemodynamically significant patent ductus arteriosus.
Methodology: As maturity and birthweight are the two major determinants of ductal closure, infants were matched as closely as possible for these parameters. An eligible patient was first assigned to the sulindac group and a subsequent patient with similar gestational age (± 1 week) and birthweight (±100 g) to the previously recruited infant would automatically receive indomethacin. A total of eight infants were enrolled in each group.
Results: The ductus arteriosus was successfully closed in all eight infants receiving indomethacin, and in seven of eight infants receiving sulindac. No significant differences were found with regards to the ductal size between the two groups at diagnosis or on each of the consecutive days of treatment ( P >0.25). More renal adverse effects were encountered in the indomethacin group. Significant differences in changes from baseline value for urine output, plasma sodium, urea and creatinine concentrations were noted at 24, 48 and 72 h after commencement of treatment between the two groups ( P <0.05). All the parameters returned to normal or pre-treatment levels 48 h after stopping therapy. Unexpectedly, severe gastrointestinal complications were encountered in the sulindac group.
Conclusions: Sulindac is capable of promoting ductal constriction in clinically stable preterm infants without compromising the renal function. The spectrum of gastrointestinal complications observed in sulindac treated infants were similar to those described for indomethacin. The use of sulindac for ductal closure in the preterm infant should remain experimental.  相似文献   
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