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11.
Simultaneous immunoelectron microscopic localization of human chorionic gonadotropin (HCG) and human placental lactogen (HPL) was examined on the same ultrathin section of human chorionic villi by means of the double labeling technique. Using specific rabbit antisera against HCG and HPL followed by goat anti-rabbit IgG-coated colloidal gold of different sizes (15 nm and 5 nm), immunoreactions of HCG were concentrated on middle-sized secretory granules of 200-300 nm and large dense bodies of 500-1000 nm, while those of HPL were exclusively located on small secretory granules of 80-180 nm. The present experiment provides direct evidence for our previous data that HCG and HPL seem to be stored in different granular components in the syncytiotrophoblast. 相似文献
12.
13.
Natural history and pathophysiology of enterocolitis in the piebald lethal mouse model of Hirschsprung's disease 总被引:3,自引:0,他引:3
T Fujimoto 《Journal of pediatric surgery》1988,23(3):237-242
A breeding colony of piebald lethal mice was established in order to study the natural history of congenital megacolon in a mouse model of Hirschsprung's disease and to investigate mucosal defense mechanisms and secretory functions in enterocolitis complicating congenital megacolon. In experiment 1, 214 mice were studied, 53 of which had congenital megacolon. All piebald lethal mice with congenital megacolon (S1/S1) died at 3 to 11 weeks of age. Two distinct patterns of mortality were identified. A majority of mice (64%) became acutely ill at 3 to 4 weeks of age and died, whereas the remainder died between 9 and 11 weeks of age. The former group of mice exhibited clinical and histologic evidence of severe enterocolitis while the latter group had massive abdominal distension and classical megacolon. In experiment 2, piebald mice with congenital megacolon were killed at the time of acute illness. Significant histologic and immunohistochemical differences were seen in the ganglionic colon between piebald mice with early clinical onset of acute illness and piebald mice with the classical clinical picture of congenital megacolon. In the former group of mice the number of immunocytes in the lamina propria was significantly higher than in control mice (P less than .001), immunoglobulin-producing cells were equally distributed throughout the lamina propria and IgA-containing cells were by far the most abundant cell type identified in the colon. In the latter group of mice, immunocyte responses were significantly low and the distribution of immunocytes markedly different, with the immunoglobulin-producing cells being located only at the deep layer of lamina propria.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
14.
We report a case of extraadrenal pheochromocytoma of Zuckerkandl imaged by dynamic magnetic resonance imaging (dynamic MRI) with a 0.5 tesla (T) machine. The dynamic MRI proved useful in disclosing the tumor clearly because of strong enhancement in its early phase. This case has the advantages of dynamic computed tomography (dynamic CT) as well as of T2-weighted spin-echo (SE) MR images. 相似文献
15.
J T Chen Y Kurokawa K Nakayama K Saito K Sakamoto K Fukuda Y Hirai T Hamada I Fujimoto K Yamauchi 《Nippon Sanka Fujinka Gakkai zasshi》1987,39(5):815-822
Bismuth subnitrate (BSN), a bismuth compound medically used for antidiarrheics, was orally administered to see whether it can reduce CDDP nephrotoxicity or not. Thirteen patients aged 19 approximately 60 with ovarian cancer entered this BSN-CDDP trial. A total of thirty three courses of BSN-CDDP treatment was undergone. BSN was administered orally at a dose of 50 mg/kg for five days before CDDP therapy. CDDP was infused for two hours. No vigorous hydration or diuresis was performed. Only 2,000 ml of saline with 20 mEq per liter of KCl was given for post-hydration. The median dose of CDDP was 100 mg/m2. The renal toxicity of BSN-CDDP treatment was minimum. 82% of the courses at the sixth day after the treatment had creatinine clearance levels which were more than 80% of those before the treatment. But twenty-four hour NAG and beta 2-microglobulin excretion were significantly increased. Bone marrow suppression and gastrointestinal disturbance were commonly observed. The results of our study indicate that BSN pretreatment reduces the renal toxicity of CDDP to some extent. 相似文献
16.
Serum lipid and apolipoprotein concentrations were measured in 37 male survivors of cerebral infarction (CI) and in 30 healthy controls. Both groups had similar total cholesterol levels, but the HDL-cholesterol level was significantly lower and the serum triglyceride level was significantly higher in the CI patients than in the controls. The ApoB level was significantly higher in the CI patients but there was no significant difference between the 2 groups in the levels of the other apolipoproteins (ApoA-I, A-II, C-II, C-III, and E). The HDL-cholesterol/ApoA-I ratio was significantly lower in the CI patients. Both the VLDL-triglyceride and VLDL-cholesterol levels were higher in the CI patients but the VLDL-cholesterol especially its cholesterol ester level was conspicuously high. A population of VLDL particles that bound to heparin on heparin-Sepharose columns was increased in the CI patients. We suggest that cholesterol ester is excessively transferred from HDL to VLDL during the disturbed catabolism of VLDL in CI patients. 相似文献
17.
H Watanabe Y Kamasaka T Higashihara T Inoue T Kuroda T Kozuka N Fujimoto Y Tada 《Clinical radiography》1989,34(12):1501-1504
We report two cases of unilateral renal angiomyolipoma. In both cases, our preoperative diagnosis was renal cell carcinoma because no low density area compatible with a fatty tissue was noted in the tumors. Histological examination revealed both tumors to be angiomyolipoma mainly composed of myomatous cells and immature fat cells. 相似文献
18.
Samuel B Adams Paul R Herz Debra L Stamper Mark J Roberts Stephane Bourquin Nirlep A Patel Karl Schneider Scott D Martin Sonya Shortkroff James G Fujimoto Mark E Brezinski 《Journal of orthopaedic research》2006,24(4):708-715
The objective of this study was to develop and verify a new technique for monitoring the progression of osteoarthritis (OA) by combining a rat model with the imaging modality optical coherence tomography (OCT). Time-sequential, in vivo, OCT imaging was performed on the left femoral condyles of 12 Wistar rats following sodium-iodoacetic acid-induced OA progression. The right femoral condyles (untreated) were also imaged and served as controls. Imaging was performed on days 0, 10, 20, 30, and 60 with an OCT system capable of acquiring images at four frames per second and an axial resolution of 5 microm. Progressive changes were analyzed using an OA scoring system. OCT successfully identified progressive cartilage degeneration as well as alteration of the cartilage/bone interface. Significant changes to both of these structures were observed in the sodium-iodoacetic acid-injected condyles. Structural changes detected with OCT were confirmed histologically. OCT in combination with a well-known model used in arthritis research represents a powerful tool for following degenerative joint disease progression in a given animal by detecting changes to the cartilage/bone interface and articular cartilage. 相似文献
19.
A Miki E Fujimoto A Mizoguchi M Arakawa C Ide 《Archives of histology and cytology》1992,55(4):407-414
Traumatic degeneration of myelinated fibers was studied by electron microscopy over 5 days following transection of mouse sciatic nerve. Special attention was paid to the mechanism which separates the degenerating part, while preserving the viable part of the axon. Immediately after transection, the opened end of the proximal stump revealed extensive subcellular changes including the disorganization of neurofilaments, and disruption of mitochondria and axonal endoplasmic reticulum (SER). Subsequently, vesicles of round and tubular profiles filled up the whole area of the stump end, and proximal to it appeared a neurofilament-predominant area characterized by randomly oriented neurofilaments and normally appearing mitochondria and SER. Characteristic membranous demarcations occurred in early periods at the border between the vesicle accumulation and the neurofilament-predominant areas, and later also within these areas. The demarcation membranes formed both by invagination of the surface plasma membrane and, probably, by fusion of the large vesicles. These became prominent with time, dividing the axoplasm into compartments of varying sizes, which gradually underwent degeneration and were liberated from the parent axon. Occurrence of autophagic vacuoles was characteristic of the degenerating portions of the parent axon. Thus, by the function of demarcation membranes, the parent axon to be preserved could remain membrane-bound, while the degenerating parts were shed off. 相似文献
20.
Intracytoplasmic lumina (ICL) in human oviduct epithelium were investigated with transmission electron microscopy. ICL were found in 43 out of 60 cases examined. They were ultra-structurally characterized by microvilli lining the lumina, periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining-positive finely granular material in the lumina, and secretory vesicles in the cytoplasm surrounding the lumina. Although ICL were observed at various heights within the epithelium, they were mainly seen in basally located cells that did not face the oviduct lumen. Various stages of formation and development of ICL were observed in the basally located epithelial cells with secretory activities. Primary ICL were originated in the cytoplasm where the secretory granules were aggregated with smooth-surfaced tubular vesicles. Electron microscopic observations after PA-TCH-SP staining revealed that ICL were formed by fusion of the secretory granules with the tubular vesicles. ICL were enlarged into round profiles by further fusion of secretory granules and tubular vesicles, and subsequently opened to the oviduct lumen, or fused to each other to develop into large extracellular cysts within the epithelium. 相似文献