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21.
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy. A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous 13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18). Results The overall positive ratios were as follows: HIF-1α, 74% of adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and 100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%; GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than in mucinous adenocarcinomas. Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared with mucinous tumors is related to the difference in their histological characteristics.  相似文献   
22.
Objective : To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation F iO2 >80% (OR 3.4; 95% Cl 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury.  相似文献   
23.
We describe a fatal case of adenovirus pneumonia accompanied by encephalitis in a neonate who showed lethargy on the 6th day and died on the 12th day. Adenoviral particles as well as viral intranuclear inclusions were noted in pulmonary alveolar epithelium cells. Neuropathological examination revealed diffuse oedema, perivascular cuffing and gliosis in the white matter. Adenovirus type 11 was isolated from lung, hilar lymph node, and brain tissue. This is the first instance of adenovirus isolation from brain tissue in a newborn infant. The viro-logical and neuropathological findings sugest the invasion of neural tissue by adenovirus and substantiate the significance of neurological symptoms observed in neonatal adenovirus infection.  相似文献   
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Histological therapeutic effects of neoadjuvant hormone therapy (NHT) in prostatic cancer were examined, focusing on the association with neuroendocrine differentiation (NED), using 69 radical prostatectomy cases. The effects of NHT were classified into 3 grades based on the extent of tumor degeneration as observed with hematoxylin and eosin staining. NED cells in the cancer were semi-quantified into 4 grades (negative, 1+, 2+, and 3+) by immunohistochemical staining of chromogranin A (CgA). According to the therapeutic effects, the cases are divided as follows: good response in 26 patients, intermediate in 20, poor in 23. The histological therapeutic effects were significantly weaker in the CgA-positive group than the CgA-negative group (p=0.02). A close relationship between the extent of CgA expression and the histological response was also demonstrated (p=0.007). In the biopsy specimens before NHT, CgA was positive in 46% (32/69) and there was no significant difference in histological therapeutic effects between the positive and negative groups. However, the therapeutic effects were significantly weaker in 22 CgA-positive cases for both biopsy and prostatectomy specimens than in 18 CgA-negative cases for both specimens (p=0.001). In conclusion, although it seems difficult to predict the therapeutic effects of NHT using the biopsy specimens of prostatic cancer, we believe that NED is negatively associated with histological response of prostatic cancer to NHT.  相似文献   
26.
Glucose transporter-1 (GLUT-1) expression was immunohistochemically analysed in a total of 268 cases of thyroid gland disease, including 129 cases of papillary carcinoma (PC), 60 cases of follicular carcinoma (FC), 57 cases of follicular adenoma, and 22 cases of adenomatous goitre. Seventy-one percent (91/129) of PC cases showed GLUT-1 expression, semi-quantitatively evaluated as: +, 21 cases (16%); 2+, 37 cases (29%); 3+, 33 cases (26%); and negative, 38 cases (29%). These positive cases were divided into two groups: 'membrane-like' pattern in 24 cases (19%), and 'cytoplasm-predominance' pattern in 67 cases (52%). GLUT-1 expression was observed in 5% (3/60) of FC cases, but all follicular adenomas and adenomatous goitres were negative for GLUT-1 (PC vs. FC, p<0.0001). Membrane-like expression was observed more frequently in non-organ-confined PCs (pT4) than in organ-confined PCs (pT1, 2, and 3) (p=0.0056). Seventy-five percent (18/24) of PC cases showing membrane-like expression were non-organ-confined. The membrane-like pattern was observed more frequently in PCs with lymph node (LN) metastasis compared to those without (p=0.0036). Ninety-two percent (22/24) of PC cases showing the membrane-like pattern were not organ-confined. Semi-quantitative analysis of glut-1 mRNA by RT-PCR showed a tendency toward higher expression in PCs compared to FCs, follicular adenomas and adenomatous goitres, and the mRNA expression in PCs with a membrane-like pattern was higher than those showing cytoplasm-predominance. We concluded that: 1) GLUT-1 is immunohistochemically useful in distinguishing PC from FC and benign diseases; 2) GLUT-1 may play an important role in the advancement of PC and LN metastasis, and its membrane-like expression is of more clinical significance than the cytoplasm-predominance pattern; and 3) glut-1 mRNA expression corresponds with the immunohistochemical expression profile.  相似文献   
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The ultrastructure of a myocardial tumor, referred to by a variety of names, which most currently is myocardial fibroma, has been studied. Although the tumor cells did not have the structure associated with protein synthesizing cells or active fibroblasts, there was evidence that they were participating in formation of the abundant stroma rich in collagen and elastic fibers in varying stages of maturity. The morphology of the stromal elements was similar to that in the surrounding myocardium and that described in the "normal" heart but differed from the elastica described in fibroelastosis.  相似文献   
30.
A 31-year-old woman was treated for atypical endometrial hyperplasia (AEH) with high-dose medroxyprogesterone acetate (MPA) therapy to preserve fertility. The AEH was found by repeated cytologic and histologic examinations to have completely disappeared with the therapy, but 3 years after her last follow up she required emergency surgery to treat severe genital bleeding. The hysterectomied uterus consisted mostly of poorly differentiated adenocarcinoma, G3 endometrioid type. Minor AEH was present in the exophytic area, in which some glands were cystically dilated. Part of the AEH had transformed into other histologic features with germ-cell-like differentiation, demonstrated by immunohistochemical positive reaction of placental alkaline phosphatase, alpha-fetoprotein, and human chorionic gonadotrophin. Recurrent AEH had undergone malignant transformation, resulting in the development of well- and poorly differentiated adenocarcinoma and tumor exhibiting germ-cell-like differentiation. The patient died of a massive tumor extension 7 months after surgery. The AEH before MPA therapy and the recurrent tumors had genetically different characteristics based on evidence of a loss of heterozygosity, detected at D8S1132 (chromosomal locus, 8q22.1) in the latter but not in the former, by analysis of genetic alterations using microsatellite markers.  相似文献   
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