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31.
胸腺瘤临床病理的预后因素研究   总被引:6,自引:2,他引:6  
目的 探讨胸腺瘤临床病理特点与预后的关系。方法 对130例胸腺瘤的重症肌无力、肿瘤大小、坏死、核分裂及包膜情况、组织学分型(按照L-B分类及M-H分类)、Massaoka临床分期等诸多因素进行分析,观察其5,10年生存率的差别,所得数据进行统计学U检验及χ^2检验。结果 重症肌无力的有无、肿瘤大小、坏死、核分裂及L-B分类均与预后无关(P>0.05);而肿瘤有无包膜、M-H分类及临床分期与生存率有明显相关性。有包膜者5,10年生存率分别为100%和93.1%,无包膜者分别为54.4%和40.0%(P<0.05)。按M-H分类,髓质型5,10年生存生存率分别为100%和79.8%,混合型分别为97.5%和88.4%,皮质为主型分别为83.3%和50.1%,皮质型分别为60.2%和29.9%,分化好的胸腺癌(WDTC)分别为43.4%和0%(P<0.05)。临床分期中Ⅰ期5,10年生存率分别为100%和93.2%,Ⅱ期分别为84.6%和78.4%,Ⅲ期分别为45.3%和19.8%,Ⅳ期分别为38.0%和0(P<0.01)。其中以细胞的异型性及有无侵犯胸腺周围器官对预后尤为重要。结论 L-B分类与预后无关;M-H分类、临床分期与预后有关,尤其是瘤细胞呈多角形和大圆形、临床侵犯胸腺外器官者对预后影响较明显。  相似文献   
32.
One of the most serious problems with endothelial cell (EC) seeding of prosthetic materials is the poor adhesion and stability of the cells. Although several substrates that improve the initial adhesion have been assayed, the EC are lost within a limited period of time. In this study we attempted to modify the hydrophobic conditions of expanded polytetrafluoroethylene (ePTFE) by treating it with ethanol prior to seeding. In addition, we created a fibroblastic matrix that was also fixed by ethanol to the prosthetic material. In vitro studies were carried out at intervals of 24 hours and 15 days after seeding. EC from umbilical cord vein and fibroblasts from skin were seeded onto disks of PTFE with a porosity of 30 µm. The results obtained show that treatment of ePTFE with ethanol prior to EC seeding modifies its permeability, preventing cellular adhesion. The seeding of fibroblasts onto ePTFE allows a coating to form at 24 hours. The EC seeded onto this matrix adhere to it, forming a monolayer that persisted throughout the entire study period. The fibroblastic matrix allows the long-term survival of the EC on ePTFE.Supported by a grant from the CICYT SAF 92-0875.  相似文献   
33.
柴胡皂甙q及其甙元的结构鉴定   总被引:4,自引:0,他引:4  
从小叶黑柴胡(Bupleurum smithii Wolffvar;parvifolium ShanetY.Li)的根中得到3个化合物,柴胡皂甙元A和Q及柴胡皂甙q。柴胡皂甙元Q和柴胡皂甙q为新化合物,根据理化性质和波谱分析,确定其结构分别为齐墩果烷-11,13(18)-二烯-3β,16β,23,28,30-五醇和3β,16β,23,28,3O-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基(1→6)-[α-L-吡喃鼠李糖基(1→4)]-β-D-吡喃葡萄糖甙。  相似文献   
34.
Grossman  LB; Buonocore  E; Modic  MT; Meaney  TF 《Radiology》1984,150(2):323-325
Forty-three patients with acquired and congenital abnormalities of the thoracic aorta were studied using digital subtraction angiography (DSA) after an intravenous bolus injection of 40 ml of contrast material. Abnormalities studied included coarctation, pseudocoarctation, Marfan syndrome, cervical aorta, double aortic arch, aneurysm, dissection, and tumor. Twenty-four patients also had conventional angiography. DSA was accurate in 95% of cases; in the other 5%, involving patients with acute type I dissection, the coronary arteries could not be seen. The authors concluded that in 92% of their patients, DSA could have replaced the standard aortogram.  相似文献   
35.
Pneumocystis carinii pneumonia studied by gallium-67 scanning   总被引:1,自引:0,他引:1  
The validity and reliability of gallium-67 (Ga-67) scanning for diagnosis and follow-up of Pneumocystis carinii pneumonia (PCP) were assessed in 34 patients thought to have pulmonary complications of acquired immunodeficiency syndrome (AIDS). Overall sensitivity was 94% and specificity 74%. Among patients with normal or equivocal chest radiographs at the time of admission, sensitivity was 86% and specificity 85%. The authors consider Ga-67 scanning a valid and reliable adjunct in the diagnosis of PCP in AIDS patients with respiratory symptoms when the chest radiograph is normal or equivocal.  相似文献   
36.
Helms  CA; Kaban  LB; McNeill  C; Dodson  T 《Radiology》1989,172(3):817-820
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.  相似文献   
37.
Objective:  Hutchinson-Gilford progeria syndrome (HGPS) is a rare early-onset accelerated senescence syndrome. In HGPS, a recently identified de novo dominant mutation of the lamin A gene ( LMNA ) produces abnormal lamin A, resulting in compromised nuclear membrane integrity. Clinical features include sclerotic skin, cardiovascular and bone abnormalities, and marked growth retardation. Craniofacial features include 'bird-like' facies, alopecia, craniofacial disproportion, and dental crowding. Our prospective study describes dental, oral soft tissue, and craniofacial bone features in HGPS.
Methods:  Fifteen patients with confirmed p.G608G LMNA mutation (1–17 years, seven males, eight females) received comprehensive oral evaluations. Anomalies of oral soft tissue, gnathic bones, and dentition were identified.
Results:  Radiographic findings included hypodontia ( n  = 7), dysmorphic teeth ( n  = 5), steep mandibular angles ( n  = 11), and thin basal bone ( n  = 11). Soft tissue findings included ogival palatal arch ( n  = 8), median sagittal palatal fissure ( n  = 7), and ankyloglossia ( n  = 7). Calculated dental ages (9 months to 11 years 2 months) were significantly lower than chronological ages (1 year 6 months to 17 years 8 months) ( P  = 0.002). Eleven children manifested a shorter mandibular body, anterior/posterior cranial base and ramus, but a larger gonial angle, compared to age/gender/race norms.
Conclusion:  Novel oral-craniofacial phenotypes and quantification of previously reported features are presented. Our findings expand the HGPS phenotype and provide additional insight into the complex pathogenesis of HGPS.  相似文献   
38.
AIM: To analyze the effect of age-period and birth cohort on gastric cancer mortality, in Brazil and across its five geographic regions, by sex, in the population over 20 years of age, as well as make projections for the period 2010-2029.METHODS: An ecological study is presented herein,which distributed gastric cancer-related deaths in Brazil and its geographic regions. The effects of ageperiod and birth cohort were calculated by the Poisson regression model and projections were made with the age-period-cohort model in the statistical program R. RESULTS: Progressive reduction of mortality rates was observed in the 1980's, and then higher and lower mortality rates were verified in the 2000's, for both sexes, in Brazil and for the South, Southeast and Midwest regions. A progressive decrease in mortality rates was observed for the Northeast(both sexes) and North(men only) regions within the period 1995-1999, followed by rising rates. CONCLUSION: Regional differences were demonstrated in the mortality rates for gastric cancer in Brazil, and the least developed regions of the country will present increases in projected mortality rates.  相似文献   
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