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101.
This report describes the morphological responses of unstimulated and stimulated non-functioning adrenocortical adenoma in culture. The removed adrenocortical adenoma was composed mainly of clear-type cells and partially had a small area of cholesterol granuloma. These adenoma cells had many lipid droplets and round to long rod-shaped mitochondria with tubular or tubulo-lamellar cristae which were similar to those in Cushing's adenoma. The non-functioning adrenocortical adenoma cells which were incubated in vitro under ACTH (10 mIU/ml) and angiotensin II (10(-6) M/ml) stimulation, were examined by phase contrast microscopy, transmission and scanning electron microscopy, and the content of cortisol and aldosterone in the culture medium was measured by radioimmunoassay. As a result of exposure of ACTH, the cultured cells revealed the retraction response and production of cortisol and aldosterone. After administration of ACTH for many days, the cultured cells showed characteristic changes in sER and mitochondria. The sER were markedly developed and packed tightly into a network of dilated tubules. Mitochondria were larger and more numerous than in the unstimulated cells. The mitochondria appeared to be entwined by the tubules of the sER. Lipid droplets decreased in number.  相似文献   
102.
Hepatocellular carcinoma (HCC) showing marked elevation of serum alpha fetoprotein (AFP) (maximum; 70942.0 ng/ml at the end stage) and serum carcinoembryonic antigen (CEA)(maximum; 7368.4 ng/ml at the end stage) was surgically resected. In the resected liver, there were two different tumor nodules which were adjacent to each other but clearly separated by a thin connective tissue. One of the nodules was a well differentiated and the other was poorly differentiated HCC. Immunoperoxidase study revealed that both CEA and AFP were localized in the tumor cells of the poorly differentiated HCC. This is the first report which clearly proved CEA synthesis in the cells of HCC. Serial staining showed that there was simultaneous synthesis of CEA and AFP in some of the tumor cells. ACTA PATHOL. JPN. 35: 969–974, 1985.  相似文献   
103.
In an attempt to clarify the cytological characteristics of the RES cells in the lymph nodes and their embryological correlations, lymph nodes and lymph node anlages of germ-free rats, nude mice, and human fetuses were light and electron microscopically examined. On the basis of differences of intracellular organelles, their behaviors for reticulum fibers and of endogenous peroxidatic activity, histiocytes should be reasonably distinguished from the cells conventionally called reticulum cells. Reticulum cells and histiocytes respectively are destined to differentiate in different directions from the early stage of development of the lymph node anlage. Sinus endothelial cells are ontogenetically originated and differentiated from the endothelial lining cells of lymphatic vessels. Primitive reticular cells are differentiated into mature reticulum cells in the lymph nodes, they transform into the lympho-reticular cells, further into lymphoblasts, and finally develop into medium-sized lymphocytes.  相似文献   
104.
Matrix metalloproteinases (MMPs) have been implicated in physiological cartilage matrix remodelling as well as in pathological and invasive extracellular matrix remodelling of tissue. Age-related changes in the gene expression patterns of MMPs in mandibular condylar cartilages (MCCs) were analysed. We examined the gene expression patterns of Mmp-8 and -13 and their substrates, Col1a1, Col2a1 and Col10a1, in MCC of growing and ageing rats. Temporomandibular joints of male Wistar rats aged 4, 8, 16 and 32 weeks were subjected to in situ hybridization analysis. Histologically, MMCs showed characteristics of growth plate cartilage at ages 4 and 8 weeks, and more closely resembled articular cartilage thereafter. Mmp-8 was expressed in the cells in all cartilaginous cell layers at ages 4 and 8 weeks, and then was localized only in the mature cells at ages 16 and 32 weeks. Whereas Mmp-13 expression was limited to the lowermost hypertrophic chondrocytes in the growth stage, mature chondrocytes instead of hypertrophic chondrocytes expressed Mmp-13 in adult non-hypertrophic MCC. Because Mmp-8 and -13 expression overlapped with Col2a1 and Col10a1, chondrocytes could play a pivotal role in degradation as well as production of the cartilaginous matrix in MCC.  相似文献   
105.
Our research group aims to develop an osteochondral composite using type II collagen gel with hydroxyapatite (HAp) deposited on one side. Soaking gels in Ca2+ and phosphate solution is indispensable to HAp deposition, so relationships between cell behavior and Ca2+ concentration were examined in two- and three-dimensional cultures. The present results indicate that 2-4 mM Ca2+ is suitable for proliferation and survival of osteoblasts, whereas slightly higher concentrations (6-8 mM) favor osteoblast differentiation and matrix mineralization in both 2- and 3-dimensional cultures. Higher concentrations (>10 mM) are cytotoxic. Purely from the perspective of calcium deposition, higher concentrations lead to increased accumulation of Ca2+. Culturing cells in phosphate-containing gel in media with Ca2+ also leads to time-dependent formation of HAp in the gel. Considering the viability of embedded cells, culturing scaffolds in media with Ca2+ concentrations around 5mM is useful for both HAp deposition and osteoblast behavior.  相似文献   
106.
The discontinuous change of the lamellar thickness with crystallization temperature was studied for low molecular weight fractions of OH-terminated poly(ethylene oxide) (PEO). IR analyses demonstrated that almost all of the molecular chain ends were associated in the molten state, whereas a large part of their ends were free in dilute solution. Discontinuous changes were observed for low molecular weight PEO fractions crystallized from the melt, whereas continuous changes were found both for PEO's crystallized from dilute solution and those with phenylated end groups crystallized from the melt. Accordingly, it was pointed out that the association of the end groups could play an important role in the crystallization mechanism and the conformation of the resultant PEO crystals.  相似文献   
107.
In an Epstein-Barr virus-transformed human B cell line we found an unusual immunoglobulin heavy chain gene rearrangement. Restriction mapping and sequencing analysis led us to conclude that VH-D and D-JH recombination took place in a single allele. Both VH-D and D-JH complexes still had their recombination signal sequences adjacent and the DNA sandwiched by these two complexes retained a germ line configuration, suggesting the potential for a secondary rearrangement resulting in a VH-D(-D)-JH formation. With this finding, we propose a novel pathway, in which the VH-D complex is an intermediate in the formation of a functional VH exon.  相似文献   
108.
A rare case of malacoplakia (MKP) of the endometrium in an 88-year-old Japanese woman is presented. By light microscopy, typical Michaelis-Gutmann bodies (M-G bodies) could be identified. Electron microscopic findings revealed M-G bodies in various stages of development. These features suggested that M-G bodies were derived from round electron-dense granules that coalesced to form phagolysosomes. Early-stage M-G bodies were manifested as small, irregular, needle-shaped areas of calcification in phagolysosomes. The present paper reviews 6 cases of endometrial MKP, 5 of which have previously been reported in the literature, and this case being the sixth, to our knowledge.  相似文献   
109.
An autopsy case of a 74-year-old male who had shown clinically hypothyroidism due to chronic atrophic thyroiditis (Hashimoto's thyroiditis), and pathologically necrotizing myopathy as a remote effect of gastric cancer was reported.
Morphological features of this necrotizing myopathy was those of carcinomatous myopathy rather than those of hypothyroid or diabetic myopathy.
As for the pathogenesis of the necrotizing myopathy (as a Group IV of polymyositis of Walton and Adams), the malignancy might have played an important role as a trigger of the secondary immunological abnormality upon a pre-exizting longstanding immune disorder of Hashimoto's thyroiditis. Pseudomembranous colitis, which was thought to be related to antibiotics (Lincomycin), was also briefly discussed.  相似文献   
110.
Role of the gene 17 protein of bacteriophage T4   总被引:1,自引:0,他引:1  
Y Kawai  S Koga 《Virology》1985,147(2):459-461
Head-related particles of bacteriophage T4 were examined by using heat leakage scanning calorimetry. The 17- particles showed two endothermic peaks on thermograms during their thermal transition process, while 49- particles gave only a single sharp endothermic peak. Thermograms of 17- particles treated with 23- defective lysate were different from those of nontreated 17- particles, and closely resembled thermograms of 49- particles. The 31- defective lysate was also capable of converting thermal properties of 17- particles. These results suggest that there is a structural difference between 17- particles and 49- particles, and that the product gene 17 of bacteriophage T4 is involved in the structural conversion of prohead to a more completed structure.  相似文献   
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