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41.
A cell line from Wilms' tumour with deletion in short arm of chromosome II   总被引:1,自引:0,他引:1  
A cell line (T3/73) from a Wilms' tumour has been established from a 9 month-old boy with aniridia. The tumour was removed in 1973. On histological examination a diagnosis of Wilms' tumour was made which showed undifferentiated areas, marked tubule formation and abundant striped muscle fibres. The tumour cells, which are fusiform, grew rapidly in culture without the addition of growth factors, and have undergone over 100 passages. Approximately 95% and 5% were positive for desmin and cytokeratin, respectively. The cell doubling time was 28 hr. Cytogenetic studies revealed a karyotype of 46,XY,del(11) (p12::p14). Although the cells stained very intensely with a monoclonal antibody that detects oncogene ras p 21 antigen, Southern blot analysis using c-Ha-ras as a probe failed to reveal an obvious deletion or amplification of either Ha-ras allele.  相似文献   
42.
Three patients with symptomatic occlusions of subclavian artery were operated upon by means of carotid subclavian bypass using ipsilateral jugular vein. The indications for this technique include unavailability of saphenous veins or contraindications to use of prosthetics. Late clinical and angiographic followup have revealed satisfactory results and no changes in caliber of vein graft.  相似文献   
43.
Summary The devastating neuropathological changes wrought by the intrathecal administration of vincristine are reported, with a detailed account of the widespread lesions in the brain and spinal cord, found in post-mortem light- and electron-microscope studies.  相似文献   
44.
2型糖尿病患者载脂蛋白E基因多态性的研究   总被引:2,自引:0,他引:2  
目的:探讨中国人2型糖尿病患者载脂蛋白E(apoE)基因多态性及其与血脂和载脂蛋白水平的关系。方法:采用聚合酶链反应-限制性酶切片段长度多态性法,分别对74例2型糖尿病患者及191例血脂、血糖正常且无糖尿病史者的apoE基因型、空腹血脂及载脂蛋白AI、AⅡ、B100、CⅡ、CⅢ及E进行全面分析。结果:2型糖尿病患者的血清甘油三酯(TG)、总胆固醇(TC),低密度脂蛋白胆固醇(LDLC),非高密度脂蛋白胆固醇(nHDLC),载脂蛋白B100、CⅡ、CⅢ、E水平及TG/HDLC比值较对照组显著升高(P<0.01);血清高密度脂蛋白胆固醇(HDLC),apoE/apoCⅢ比值显著降低(P<0.05)。2型糖尿病组与对照组apoE基因频率分布无显著性差异(P>0.05)。携带ε2等位基因组血清TG/HDLC比值较E3/3基因型显著降低;而携带ε4等位基因组血清apoAⅡ水平较E3/3基因型及携带ε2等位基因组显著升高(P<0.001)。结论:2型糖尿病患者apoE基因多态性与血TG/HDLC及apoAⅡ有一定关联。  相似文献   
45.
Over a 5-year period from 1985 to 1989, 2760 patients underwent open heart surgery at the University Hospital of Wales. Of these, 44 (1.6%, 35 men, mean age 61 years) developed median sternotomy dehiscence 2-40 (median 9) days after surgery. Infection was an associated factor in 18 patients (41%) and Staphylococcus aureus the predominant isolate in seven of those. Thirty-seven patients underwent rewiring of the sternotomy wound and seven patients underwent debridement, removal of wires and delayed closure. In those undergoing rewiring, sternal stability was maintained in 34 patients (92%). There were seven deaths (16%), of which two were considered to be wound-related. Median hospital stay of survivors was 34 (range 16-84) days. Comparison with 88 matched controls by univariate analysis showed preoperative chronic obstructive airways disease, reduced FEV1/FVC ratio (both P < 0.001) and smoking (P < 0.05) were all more common in the dehiscence group. In addition, reoperation for bleeding (P < 0.05), prolonged bypass time, postoperative ventilation period and length of stay in the intensive care unit (all P < 0.001) were more common in the study group.  相似文献   
46.
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48.
Experimental columnar metaplasia in the canine oesophagus   总被引:7,自引:0,他引:7  
Regeneration of canine oesophageal mucosa was studied under basal conditions and in the presence of gastro-oesophageal reflux. In normal circumstances mucosal defects in the oesophagus regenerate by squamous epithelium. In the presence of gastro-oesophageal reflux of either acid or a combination of acid and bile, regeneration was frequently by columnar epithelium (Barrett's oesophagus). This columnar regeneration was not seen with bile reflux alone. By the use of squamous barriers to proximal migration of columnar epithelium in the stomach, it was demonstrated that columnar re-epithelialization may occur from cells intrinsic to the oesophagus and is not dependent on proximal migration of cardiac columnar epithelium. The cell of origin of this epithelium may be located in oesophageal gland ducts and is likely to be a multipotential stem cell since the regenerated columnar epithelium may contain goblet and parietal cells not normally found in the oesophagus. This epithelium is morphologically distinct on mucin histochemistry from cardiac columnar epithelium. These findings support the concept that Barrett's epithelium is metaplastic.  相似文献   
49.
The synthesis of acute-phase proteins by the liver during sepsis has been thought to be induced primarily by monokines released from activated macrophages, although glucocorticoid hormones may also stimulate this process to a lesser degree. According to this concept, synthesis of these proteins following administration of bacterial endotoxins would be an indirect effect and would not reflect a direct interaction of the endotoxin molecule with the hepatic parenchymal cell. We observed, however, that the synthesis of a 23-kilodalton protein was stimulated directly by the addition of lipopolysaccharide to cultures of primary mouse hepatocytes. The synthesis of this protein was also stimulated by glucocorticoids and interleukin 1. These findings demonstrate that certain hepatic proteins are subject to complex regulation by several factors thought to be important mediators of sepsis; in addition, they suggest that hepatic parenchymal cells may have the intrinsic capacity to respond directly to bacterial endotoxins.  相似文献   
50.
One hundred thirty-one children underwent rigid bronchoscopy under general anesthesia for suspected aspirated foreign bodies. There were 79 boys and 52 girls, with a mean age of 2.1 years. Physical examination showed decreased breath sounds (n = 130) and wheezing (n = 119) over the affected site. Chest roentgenograms were diagnostic or suggestive of aspirated foreign bodies in 127 cases (97%). Radiopaque lesions were noted on roentgenograms in ten cases. Four infants had a preoperative hypoxic arrest. Two patients had negative results of bronchoscopy (1.5%). Extraction of the aspirated foreign body was carried out at laryngoscopy in two patients and by forceps under direct vision at bronchoscopy in 97 patients. A Fogarty catheter was used in 12 cases. Postendoscopic complications included fever (n = 27), pulmonary infiltrate (n = 11), ventilatory support (n = 4), and pneumothorax (n = 2). Rigid bronchoscopy for aspirated foreign body in children is a safe, effective, and sometimes life-saving procedure. Morbidity is low and mortality is zero.  相似文献   
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