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101.
102.
The effect of polyanions on the formation of mixed dimers of methylene blue ( 1 ) and trypaflavine ( 2 ), methylene blue ( 1 ) and phenosafranine ( 3 ), and methylene blue ( 1 ) and pyronine G ( 4 ) was investigated spectrophotometrically. The following polyanions were used: poly(potassium styrenesulfonate) (PSS), poly(potassium vinyl sulfate) (PVS), and poly(sodium acrylate) (PAA). On addition of polyanions, the formation of mixed dimers was enhanced largely. Thermodynamic parameters inferred that the enhancement of the formation of mixed dimers in the presence of polyanions resulted from an entropic factor.  相似文献   
103.
The structural effect of polyanions on the binding type of methylene blue ( 1 ) was investigated spectrophotometrically. 1 was bound to poly(potassium styrenesulfonate) (PSS) and poly(sodium 4-vinylphenylsulfate) (SVS) in the dimeric or slightly aggregated form and to poly(sodium vinylsulfonate) (SVF) and poly(potassium vinyl sulfate) (PVS) in the highly aggregated (polymeric) form. It was found that the flexibility of polyanions plays an important rǒle in the aggregation of bound 1 and that the difference between ? SO and ? OSO as binding site is not a significant factor.  相似文献   
104.
A case of adrenocortical carcinoma associated with congenital heart defect in a 6-month-old Japanese girl is reported. A fist-sized tumor was incidentally noted in the right hypochondrium upon admission for cardiac surgery. No clinical endocrinopathy was evident in this case. The resected tumor was encapsulated with smooth surface and no invasion to adjacent tissues or organs was observed. Histologically, the tumor was composed of small cells with granular or clear cytoplasm, and occasional giant cells with single or multiple nuclei. By electron microscopy, the tumor cells showed various nuclear contours with distinct nucleoli and had a moderate amount of cytoplasm containing abundant rough endoplasmic reticulum and mitochondria with variable-sized electron-dense granules. Intercellular desmosome-llke junctions were observed in some tumor cells. Immunohistochemlcally, the tumor cells contained granules positive for estriol, progesterone and Cortisol. These morphological findings including electron microscopic features suggested that the tumor cells had a malignant character.  相似文献   
105.
Three cases of pancreatoblastoma in children were examined immunohis-tochemically and the results were compared with those of pancreatic duct carcinoma in adults. The pancreatoblastoma demonstrated positive reactions to α-fetoprotein (AFP) (67%: 2/3), α-1-antitrypsin (AAT) (100%: 3/3), carcinoembryonic antigen (CEA) (67% : 2/3) and keratin (33% : 1/3), although CEA was only weakly positive in both cases. On the other hand, adult pancreatic duct carcinoma showed positive reactions as follows; AFP: 3% (1/29), AAT: 21% (6/29), CEA: 97% (28/29) and keratin: 93% (27/29). Also, endocrine substances including insulin, glucagon and somatostatin were all negative in the pancreatoblastomas. Two cases of pancreatoblastoma which were immunohistochemically positive for AFP also showed elevation of the serum AFP level clinically. The different expressive pattern of oncofetal antigens in pancreatoblastoma as compared with pancreatic duct carcinoma in adults may provide further supporting evidence for the embryonic nature of pancreatoblastoma, and suggests that such a pattern might be used as a tumor marker for pancreatoblastoma. ACTA PATHOL. JPN. 37 : 1581-1590, 1987.  相似文献   
106.
Heme oxygenase (HO), the heme-degrading enzyme, plays an important role in heme catabolism. Among three isozymes, HO-1 is an inducible form expressed mainly in macrophages. In rat ontogeny, HO-1 immunoreactivity was detected in mononuclear cells in the yolk sac at 10 days of gestation. HO-1-expressing cells were then detected in the fetal liver and their numbers increased during the gestational period. The numbers of HO-1-positive cells and HO-1 mRNA levels in the liver peaked at 18 days of gestation. Most of the macrophages expressed both HO-1 and a macrophage scavenger receptor. Macrophages in the fetal liver showed marked hemophagocytosis. Macrophages in the lung, spleen, bone marrow, and other tissues also expressed HO-1. HO-1 immunoreactivity was also observed in syncytial cells of the chorionic villi, the endodermal layer of the yolk sac, and renal tubules of the fetus. Intestinal mucosal epithelial cells expressed HO-1 after birth. These findings imply that HO-1 is crucial for macrophages in heme catabolism from an early stage of ontogeny. HO-1 expression in non-macrophagic cells may be required for other purposes such as protection from oxidative stress and various stimuli.  相似文献   
107.
BACKGROUND: In Asian countries, there is no epidemiological report on seasonal affective disorder (SAD) in different age groups and different geographic regions surveyed at the same time. The aim of this study was to estimate the prevalence rates of SAD and risk factors for SAD in adults and high-school students, with special reference to the difference of winter SAD between northern and southern regions in Japan. METHODS: A total of 3237 high-school students and 4858 workers living in Japan (31.3-43.5 degrees N) responded to this epidemiological survey using Japanese version of the Seasonal Pattern Assessment Questionnaire (SPAQ). RESULTS: The overall prevalence rates of winter SAD (subsyndromal winter SAD) and summer SAD (subsyndromal summer SAD) in high-school students were 0.91(2.21) and 0.81(2.57)%, respectively. In workers, these rates were 0.45(1.16) and 0.43(0.71)%, respectively. Although no regional difference was noted in high-school students with winter seasonal type, the estimated odds ratio of this type for northern workers was nearly 3-fold higher than the southern counterparts. The prevalence rates of each seasonal type were not significantly different between two sexes in both age groups. No clear dependence on latitude was seen with regard to summer SAD in both age groups. LIMITATIONS: The effect of climate on SAD could not be entirely excluded from geophysical factor as indexed by latitude. CONCLUSIONS: SAD was less common in adults than in high-school students. While latitude was a major determinant of winter type in adults, socio-cultural factors or other contributing factors might affect the development of this type in high-school students.  相似文献   
108.
109.
Coxsackievirus B is the most common cause of viral myocarditis and is particularly virulent in neonates and children. Adenovirus is also a leading cause of the disease. The determinant of tropism for both viruses is considered to be the expression of coxsackievirus and adenovirus receptor (CAR) in target organs. However, developmental change and physiological localization of CAR in the heart are unknown. We examined expression levels of CAR in rat hearts by quantitative real-time polymerase chain reaction and Western blot analysis and found that CAR decreased gradually during postnatal development, although CAR was detectable, even in adults. Immunohistochemistry revealed CAR on the whole surface of cardiomyocytes in immature rat hearts. In contrast, CAR was detected predominantly on intercalated disks in the adult heart and was accumulated especially at the contact point between the cultured cardiomyocytes, even though they were prepared from the neonatal rat heart. In conclusion, CAR was expressed abundantly on the whole surface of cardiomyocytes in immature rat hearts. Both the expression level and the localization of CAR are possible determinants of the susceptibility to viral myocarditis of neonates and children.  相似文献   
110.
Dendritic cell-like cells (Mo-DCs) generated from peripheral blood monocytes with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been used as tools to treat cancer patients (DC-vaccines). Because Mo-DCs have multiple antigen presentation-related functions, including phagocytosis, migration, cytokine production, and T cell stimulation, establishment of a method for simultaneously evaluating the various functions of Mo-DCs is important. We developed a new in vitro three-dimensional two-layer collagen matrix culture model that consists of a collagen gel containing Mo-DCs as the lower layer and a collagen gel containing necrotic GCTM-1 tumor cells and/or T cells as the upper layer. We used this system to observe simultaneously multiple functions of Mo-DCs by phase-contrast or fluorescence microscopy and to assess IL-12 secretion during more than 2 weeks of culture. We also observed interactions between Mo-DCs and necrotic GCTM-1 or T cells on an individual cell basis by time-lapse videomicroscopy. In addition, we collected Mo-DCs from the collagen gels by collagenase treatment and analyzed the expression of antigen presentation-related molecules such as HLA-DR, CD80, CD83, and CD86 on Mo-DCs. This model may be a useful tool for evaluation of the various functions of Mo-DCs used as DC vaccines and for studies of the complex behaviors of Mo-DCs in vivo.  相似文献   
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