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81.
Alterations of the myocardial skeletal framework in acute myocardial infarction with and without ventricular rupture. A preliminary report 总被引:1,自引:0,他引:1
S M Factor T F Robinson R Dominitz S H Cho 《The American journal of cardiovascular pathology》1987,1(1):91-97
Thinning and dilatation (expansion) of the infarct region and complete rupture of the ventricular wall are significant complications of acute transmural myocardial infarction associated with increased morbidity and mortality. The pathogenesis of these related events is unknown. Recent studies of myocardial connective tissue have delineated an extensive array of intercellular and pericellular structures which serve as a skeletal framework and which may modulate contractile activity. We have employed a modified silver impregnation method to visualize the connective tissue components by light microscopy. To explore whether the skeletal framework is altered in acute myocardial infarction with and without ventricular rupture, we studied 9 human hearts at autopsy, and 4 canine infarcts of known duration. The human infarctions included 4 nonruptured cases with infarcts 1-5 days old, and 5 ruptured cases with infarcts 3-10 days old. Sections from normal, lateral, and central infarct or ventricular rupture sites were stained with silver. The normal tissue from each heart served as a control. Silver staining was moderately decreased in the lateral infarct zones, and markedly decreased in the central non-ruptured infarct zones. In the 5 ventricular rupture cases, the rupture site had no silver staining. A similar pattern was observed in the 4 canine infarcts. Thus, we conclude that the skeletal framework is markedly altered in the central zone of acute myocardial infarction. The acute changes of silver stained connective tissue may contribute significantly to the development of infarct expansion or ventricular wall rupture. 相似文献
82.
83.
Doki Chun Jae K. Chung Dong T. Cho Sung Yong Seol Ryunbin Tak 《Journal of clinical microbiology》1977,5(3):385-386
Almost all strains of Vibrio parahaemolyticus produced Kanagawa-type hemolysis on media of high salt content in the presence of fermentable carbohydrates. 相似文献
84.
Localized in vivo proton magnetic resonance spectroscopy ((1)H-MRS) has been used to measure the metabolic status of the human brain in a non-invasive manner; thus, it is often called "a non-invasive biochemical assay". MRS is more sensitive than magnetic resonance imaging (MRI) in detecting ischemic damage by measuring the metabolic changes that occur prior to the anatomic changes. We report a patient who presented with innominate artery occlusion and symptoms of posterior circulation insufficiency and showed favorable metabolic changes by (1)H-MRS after revascularization. He showed no visible lesion in brain MRI, but in (1)H-MRS, decreased N-acetylaspartate (NAA) signal was noted in a resting state.After revascularization, both symptomatic improvement and recovery of NAA signal were observed. (1)H-MRS may provide valuable clinical information in diagnosis and management of cerebral hypoperfusion at a much earlier stage prior to the anatomic changes. 相似文献
85.
One hundred and eleven zoo birds representing 49 species in 14 orders were examined for Marek's disease (MD) herpesvirus (MDHV) infection. MDHV was isolated from 10 birds, all belonging to genus Gallus. The precipitating antibodies against MDHV were demonstrated only in the Gallus birds, when 51 selected birds including 34 Galliformes and 17 other birds representing 12 species from nine orders were examined. The 10 MDHV isolates all induced morphologically similar plaques in cell cultures closely resembling those of HN strain, a low pathogenic isolate of MDHV. Six of the 10 isolates, when inoculated into an experimental line of chickens highly susceptible to MD, caused only a minimal degree of histologic lesions without causing clinical MD, gross MD lesions, or deaths from MD. Natural hosts of MD are probably Galliformes, primarily affecting Gallus and less often other genera of Galliformes. 相似文献
86.
87.
Malignant granular cell tumor at the retrotracheal space 总被引:3,自引:0,他引:3
We report a case of an extremely rare neoplasm, malignant granular cell tumor (MGCT). The patient was a 21-year-old woman, who was 5 months pregnant. The tumor occurred in the retrotracheal space, extending from the level of the larynx to the thoracic inlet. In addition, there were multiple, variable-sized tumor nodules within both lung fields on chest CT scan. Histologically, tissue biopsied from the periphery of the tumor consisted of solid sheets of large ovoid cells with ample, eosinophilic cytoplasm, eccentric nuclei, and prominent nucleoli. Each cell showed slight atypism of the nuclei. There was a focal necrosis at the periphery of the lesion. These cells stained strongly for S-100 protein, neuron-specific enolase (NSE) and CD68. On electron microscopy, the tumor cells contained autophagic vacuoles. The patient refused further treatment and died 7 months later. The exact cause of death was not known. Until now, the diagnosis of MGCTs has been made only when metastasis and an aggressive clinical course are identified, although some observers advocate that some histologic features such as nuclear pleomorphism, necrosis, and the presence of any mitotic activity are indicative of malignancy. These histologic findings are not easily detectable in every case of MGCT, as in our case. So the diagnosis of a MGCT should be considered in cases with aggressive clinical findings and some histologic features, such as necrosis, nuclear atypism, and mitotic activities, which could suggest the malignant behavior of this neoplasm. 相似文献
88.
Coronary microvascular abnormalities in the hypertensive-diabetic rat. A primary cause of cardiomyopathy? 总被引:2,自引:1,他引:2 下载免费PDF全文
S M Factor T Minase S Cho F Fein J M Capasso E H Sonnenblick 《The American journal of pathology》1984,116(1):9-20
The authors have continued their investigation of the hypertensive-diabetic (HD) rat by evaluating changes in the myocardial microvasculature in this model. Perfusion of HD animals in vivo with a silicone rubber solution revealed numerous areas of microvascular tortuosity, focal constrictions, and microaneurysm formation. These alterations were present to a lesser extent in normoglycemic hypertensive (H) rats, and were distinctly rare in normotensive diabetic rats and unaffected control animals. Quantitation of these vascular lesions revealed highly significant differences between HD animals and the other three groups, with hypertensive rats intermediate between HD rats and diabetic control rats. Areas of pronounced arteriolar constriction were also identified in the HD and H animals with the use of serial sections of Epon-embedded myocardium. It is believed that these lesions represent dynamic changes in the microcirculation, which may cause segmental reperfusion injury to the myocardium, leading to focal replacement fibrosis. Interstitial scarring may result from increased leakiness of small vessels exacerbated by the combined disease. The authors propose that the additive effects of hypertension and diabetes mellitus on the myocardial microcirculation may be a primary cause of cardiomyopathy in this model of human disease. 相似文献
89.
Chung JH Yang JH Song MJ Cho JY Lee YH Park SY Moon MJ Lim HJ Choi JS Kim JO Shin JS Ahn HK Han JY Kim MY Choi KH Ryu HM 《Journal of Korean medical science》2004,19(1):32-36
The aim of present study was to establish normative data for the distribution of nuchal translucency (NT) thickness in normal Korean fetuses. The data were collected from pregnant women with singleton pregnancies in whom fetal ultrasound was performed and the fetal NT thickness was measured between 11 and 14 weeks of gestation. Among them, a total of 2,577 fetuses with a known normal outcome were included in this study. The distribution of multiple of median (MoM) values of the NT thickness with crown-rump length (CRL) in 10-mm intervals and the 95th percentile of MoM were calculated with the linear regression method. The present study showed that NT measurements increase with increasing CRL and a false positive rate increases with increasing gestational age. Therefore, a fixed cut-off point through the first trimester was not appropriate and each NT measurement should be examined according to the gestational age. The present study offers normative data of the fetal NT thickness in a Korean population, which can be used as reference for screening chromosomal aberrations or other congenital abnormalities in the first trimester. 相似文献
90.
Lectin affinity electrophoresis in a yolk sac tumour in the vagina with yolk sac tumour-type glycoform of alpha fetoprotein. 下载免费PDF全文
R Yamamoto K Taketa Y Ebina Y Cho H Hareyama N Sakuragi S Makinoda K Kobayashi S Nishi S Fujimoto 《Journal of clinical pathology》1997,50(10):856-858
AIMS: To investigate a potential diagnostic use of alpha fetoprotein (alpha FP) isoform analysis by lectin affinity electrophoresis to distinguish between endodermal sinus tumours arising in the vagina in infants from those at other sites. METHODS: alpha FP in the serum of a patient with a vaginal endodermal sinus tumour was analysed for its isoforms by lectin affinity electrophoresis. The isoforms were compared with that of cord serum, sera of hepatoid adenocarcinoma of the uterus, and endodermal sinus tumour of the ovary. RESULTS: The isoforms of alpha FP obtained by lectin affinity electrophoresis in the serum of the patient with vaginal endodermal sinus tumour differed from the isoforms of alpha FP in the cord serum of normal neonates, and sera of patients with hepatoid adenocarcinoma of the uterus or endodermal sinus tumour of the ovary. CONCLUSIONS: Endodermal sinus tumour arising in the vagina could be distinguished from that in the ovary by the lectin affinity electrophoresis, and a potential diagnostic use of alpha FP isoform analysis by the lectin affinity electrophoresis for the detection of the endodermal sinus tumour in infants was demonstrated. 相似文献