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991.
Differential distribution of brush cells in the rat lung 总被引:2,自引:0,他引:2
The distribution of brush cells in the rat lung was studied using electron microscopic morphometry. Samples were taken from six distinctive anatomical regions. Tissue from the trachea, lobar bronchi, terminal bronchioles, first alveolar duct bifurcations, proximal alveolar regions, and the distal alveolar region were isolated and embedded in Epox 812. Aside from the trachea and the lobar bronchi, the other four regions were isolated from embedded tissue using microdissection techniques. Electron micrographs taken from thin sections of these samples were analyzed. It was found that brush cells made up 10% of the volume of epithelium covering the first alveolar duct bifurcation. Approximately 2% of the proximal alveolar epithelium, 1.4% of the terminal bronchiolar epithelium, and 3% of the tracheal epithelium were made up of brush cells. No brush-bordered epithelium was found in the lobar bronchi or in the distal alveolar walls. We conclude that brush cells have a distinct spatial location in the lung, being in high concentration in the trachea and in areas where first generation alveolar ducts bifurcate. The highest density was on the bifurcation of the first alveolar ducts, and their density decreased radially from this region. 相似文献
992.
V L Kinnula A R Whorton L Y Chang J D Crapo 《American journal of respiratory cell and molecular biology》1992,6(2):175-182
Endogenous hydrogen peroxide (H2O2) release from aortic endothelial cells was studied in the presence of antioxidant enzyme inhibitors, mitochondrial inhibitors, a microsomal cytochrome P-450 inhibitor, and after oxidative stress induced with H2O2 or menadione. Extracellular H2O2 generation was determined spectrofluorometrically using 3-methoxy-4-hydroxy phenylacetic acid, and intracellular H2O2 production (in or near peroxisomes) was measured indirectly using aminotriazole, which inactivates catalase in the presence of H2O2. Extracellular H2O2 release was 0.079 +/- 0.005 nmol/min/mg protein in Hanks' balanced salt solution, was constant during a 120-min incubation period, and was not affected by the cell passage number. The half-life for catalase inactivation with aminotriazole was 23 min. Inhibition of catalase, glutathione reductase, or gamma-glutamylcysteine synthetase did not change the rate of extracellular release of H2O2. Furthermore, inhibition of the mitochondrial respiratory chain (rotenone, antimycin A) or microsomal cytochrome P-450 (8-methoxypsoralen) did not change extracellular H2O2 release or intracellular H2O2 production (at peroxisomes) by endothelial cells or cells in which glutathione reductase was inactivated. When the cells were exposed to exogenous H2O2 (30 microM), extracellular H2O2 was scavenged primarily by the glutathione redox pathway. Exogenously added H2O2 (100 microM) changed intracellular H2O2 production (in or near peroxisomes) only when the glutathione redox cycle was inactivated. Menadione (20 microM), which undergoes intracellular redox cycling, increased extracellular H2O2 release almost 4-fold to 0.3 nmol/min/mg protein. Furthermore, menadione increased peroxisomal H2O2 levels and decreased the half-life for catalase inactivation in the presence of aminotriazole to 13 min. Catalase inhibition increased extracellular H2O2 release during menadione treatment, indicating that H2O2 can diffuse across the plasma membrane during oxidant stress.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
TM Fandel M Pfnür SC Schäfer P Bacchetti FW Mast C Corinth M Ansorge SW Melchior JW Thüroff CJ Kirkpatrick H‐A Lehr 《The Journal of pathology》2008,216(2):193-200
In the histomorphological grading of prostate carcinoma, pathologists have regularly assigned comparable scores for the architectural Gleason and the now‐obsolete nuclear World Health Organization (WHO) grading systems. Although both systems demonstrate good correspondence between grade and survival, they are based on fundamentally different biological criteria. We tested the hypothesis that this apparent concurrence between the two grading systems originates from an interpretation bias in the minds of diagnostic pathologists, rather than reflecting a biological reality. Three pathologists graded 178 prostatectomy specimens, assigning Gleason and WHO scores on glass slides and on digital images of nuclei isolated out of their architectural context. The results were analysed with respect to interdependencies among the grading systems, to tumour recurrence (PSA relapse > 0.1 ng/ml at 48 months) and robust nuclear morphometry, as assessed by computer‐assisted image analysis. WHO and Gleason grades were strongly correlated (r = 0.82) and demonstrated identical prognostic power. However, WHO grades correlated poorly with nuclear morphology (r = 0.19). Grading of nuclei isolated out of their architectural context significantly improved accuracy for nuclear morphology (r = 0.55), but the prognostic power was virtually lost. In conclusion, the architectural organization of a tumour, which the pathologist cannot avoid noticing during initial slide viewing at low magnification, unwittingly influences the subsequent nuclear grade assignment. In our study, the prognostic power of the WHO grading system was dependent on visual assessment of tumour growth pattern. We demonstrate for the first time the influence a cognitive bias can have in the generation of an error in diagnostic pathology and highlight a considerable problem in histopathological tumour grading. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
994.
来氟米特对大鼠不同器官移植排斥反应的抑制作用 总被引:3,自引:0,他引:3
目的:验证来氟米特(leflunomide)对同种异体急性排斥反应的抑制作用。方法:60只成年Lewis雄性大鼠作为受体,ACI大鼠作为供体,分别行原位肝脏、小肠、肾脏以及异位心脏、胰腺移植。除对照组外,给予每只受体来氟米特5 mg.kg-1.d-1治疗14 d。结果:与对照组比较,来氟米特可显著延长受体及移植物存活时间。其中,来氟米特可将2/6肾移植受体及5/5肝移植受体存活时间延长至100 d以上。结论:来氟米特可显著延缓大鼠同种异体小肠、心脏及胰腺器官移植排斥反应;可有效控制肝脏及肾脏移植排斥反应。 相似文献
995.
The evaluation of mammographic interpretations is a difficult challenge for a professional quality assessment program. As most images are read by a single observer and pathologic proof is obtained only if prompted by the report or if clinical symptoms warrant surgical intervention, it is difficult to construct a meaningful quality assessment program. The authors designed a program on the basis of a mammographic coding system that allows both individual physicians and practice groups to be evaluated. The program examines mammographic reports to determine the consistency of reporting by each physician and by the entire group. In addition, the program facilitated periodic evaluation of physicians with use of test cases. The coding system provided an easy method of correlating the mammographic reports with pathology reports from biopsy specimens, allowing a more thorough examination of possible systematic errors in the evaluation of the examinations, as well as enabling calculation of the positive predictive value for the diagnosis of cancer. The professional quality assessment program can be easily implemented in a busy clinical setting to evaluate whether mammograms were read consistently and "correctly" and to provide a method of continuing education for the physicians. 相似文献
996.
重型颅脑损伤后高血糖82例 总被引:1,自引:1,他引:0
1 临床资料 1996 - 0 8/ 1999- 0 8我科共收治重型颅脑损伤患者 82 (男 5 8,女 2 4)例 ,年龄 7~ 81(平均 32 .4)岁 .本组患者伤前均无糖尿病史 .GCS评分均 <8分 .其中 6~ 8分的 42例 ;3~ 5分的 2 8例 ;3分以下的 12例 .发病至入院时间均在2 4h以内 .应用美国产“One Touch”血糖仪每日在床旁测空腹血糖 1次[1 ] ,连续测 7d.对于空腹血糖 >10 mmol· L者 ,给予低糖饮食 ,不用激素 ,少量应用甘露醇 ,适当应用胰岛素及乳酸林格液等治疗 .在 82例中 ,首次测血糖值 >10 mmol· L[2 ] 的 49例 ,最高值为 19.4mmol· L ;经上述治疗 ,结果… 相似文献
997.
Colonic perforation following mild abdominal trauma in a patient with Crohn's disease: a case report
John Bunni Simon JW Monkhouse Christopher P Armstrong 《World journal of emergency surgery : WJES》2008,3(1):13
Colonic perforation following mild abdominal trauma in patients with Crohn's disease is a rare occurrence. We present a case
of a 21 year old Crohn's sufferer, who presented to the emergency department with signs of shock and peritonitis following
minor abdominal trauma. A computed tomography (CT) scan revealed ascending colonic perforation and he underwent a subsequent
right hemicolectomy. This is the first UK report of a patient with inflammatory bowel disease suffering colonic perforation
following minimal trauma. 相似文献
998.
目的:探讨结构性培训课程对员工掌握职业复康服务知识的效用.方法:2006-04开始从广州市残疾人士职业培训中心招募参与课程的同工有23名,男14名,女9名,年龄23~51岁,平均年龄31.3岁,服务年资6个月~4年,平均年资2年.安排23位员工接受一连8节结构性课程,在课程前后以相同的测验卷测试员工的表现,从而测试课程的成效.课程内容:一连4 d的培训课程共分为8节,每节3个小时.每节均有特定的主题:①复康理念.②辅导工作理论及技巧.③职业复康需要.④评估工具应用.⑤训练流程之制定及管理.⑥市场推广及顾客管理.⑦开发就业及训练机会.⑧就业跟进及在职支援.结果:上课前的测验成绩及上课后的测验成绩差异有显著性(t=0.986,P<0.001).总结:结构性培训课程能帮助员工掌握职业复康服务的理论及实务. 相似文献
999.
Pierre-Yves Berclaz Haitao Gao Janet A. Tobian Diana L. Swanson David M. Webb Robert O. Crapo Robert L. Jensen 《Diabetes research and clinical practice》2009,83(1):e1-e3
Using data from NHANES III, we evaluated the effect of diabetes on the age-related decline in lung function. The Diabetes group (n = 471) had significantly lower mean FEV1 and FVC values than the No Diabetes group (n = 4317), but pulmonary function declined with increasing age at a similar rate for both groups. 相似文献