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101.
A mapping study of cystectomy specimens in three cases of pure squamous cell carcinoma and 28 cases with transitional cell carcinoma with squamous differentiation is described, with an emphasis on the histogenesis of pure squamous cell carcinoma. Two of the three cases of pure squamous cell carcinoma had extensive benign keratinizing mucosa and an atypical squamous metaplastic mucosa contiguous with the tumour. These pure squamous cell carcinomas seemed to be derived from the squamous metaplasia. On the other hand, in all except one of the cases of transitional cell carcinoma with squamous differentiation, there was neither benign keratinizing nor atypical squamous metaplastic mucosa in the bladder. The quantitative amounts of both the transitional cell and squamous components differed from case to case in 28 cases with transitional cell carcinoma with squamous differentiation. Five of the 28 had a tumour composed predominantly of a squamous component with minute transitional cell components at the margin. In another two cases, transitional carcinoma in situ or satellite tumours of transitional cells were present adjacent to the main tumour which was composed of squamous cell carcinoma alone. We think these seven tumours originated as a result of extensive squamous differentiation in the transitional cell carcinomas. These features may indicate two forms of histogenesis of pure squamous cell carcinoma. The first is malignant transformation on the basis of squamous metaplasia of the bladder mucosa and the second is extensive squamous differentiation in a pre-existing transitional cell carcinoma.  相似文献   
102.
Of 1-cyclohexyl-4-[2-(3-hydroxyphenyl)-1-phenylethyl]piperazine (I) and its 1-(3-methyl-2-butenyl) derivative (II), the S(+)-isomers were analgesically more active than either their R (-)-isomers or their racemates, having 15 to 44 times the potency of morphine in mice and rats. R (-)-I had comparable analgesic activity to morphine R (-)-II to pentazocine in mice, rats and dogs and they were nearly equipotent with pentazocine in reversing some actions of morphine. The S (+)-isomers and racemates lacked this action. R (-)-II required about 10 times more naloxone to reverse its analgesic activity than was needed to antagonise the S (+)-isomers, morphine and pentazocine. The S (+)-isomers and racemates produce a typical Straub tail reaction and increased spontaneous locomotor activity in mice, but the R (-)-isomers did not. R (-)-II had no significant physical dependence liability in mice, rats and monkeys. From these results, it is suggested that the compounds show an uncommon stereoselectivity in comparison with morphine and its surrogates, and that R (-)-II is worth investigating further as a narcotic antagonist analgesic.  相似文献   
103.
A potential use of 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) to solubilize methyl paraben and to suppress its percutaneous absorption was examined, and compared with nonionic surfactant HCO-60. HP-β-CyD significantly increased the solubility of methyl paraben in water, where the apparent 1:1 stability constant of the soluble complex was determined to be 2150 M?1. The in-vitro cutaneous permeability of methyl paraben through an isolated skin of hairless mouse was suppressed by HP-β-CyD, thus promoting the bioconversion of methyl paraben to the less toxic metabolite, p-hydroxybenzoic acid (p-HBA) in the epidermis. These effects of HP-β-CyD were greater than those of HCO-60. HP-β-CyD (2% w/v) reduced the in-vivo percutaneous absorption of methyl paraben by 66% 24 h after the topical application of a solution containing [14C]methyl paraben to hairless mouse skin. Additionally, the percutaneous absorption of [14C]HP-β-CyD was confirmed to be extremely low. These results suggest that HP-β-CyD is useful in liquid preparations of methyl paraben for topical application.  相似文献   
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Erythropoietin (EPO)-producing renal cell carcinomas in two hemodialysis patients are reported. Despite deteriorated kidney function, these patients did not manifest anemia at diagnosis and their elevated serum EPO levels rapidly returned to within the normal range after nephrectomy. Immunohistochemical staining of the resected specimens showed production of erythropoietin in the tumor cells in one case and in the lining cells of the cyst wall in the other case. Renal cell carcinoma could cause an increase of blood hematocrit level in dialysis patients.  相似文献   
106.
Abstract A 72-year-old man complaining of upper abdominal discomfort was diagnosed as having retroperitoneal liposarcoma by means of diagnostic imaging. He then underwent an operation. One mass existed on the curvatura ventriculi major, extending to the hilum splenicum and pressing back the pancreal head and body. There was another mass to the left of the first, situated on the ventral side of the left kidney. Also, another mass was intramurally found adjacent to the curvatura ventriculi major. Histologically, the mass on the curvatura ventriculi major ranged from the peritoneal cavity to the retroperitoneum Its intraperitoneal portion was classified as a differentiated lipoma-like type and the retroperitoneal mass was of mucous type. The mass on the left kidney was of a differentiated fibrosing type. The intramural mass in the gastric curvature was found to be a differentiated lipoma-like type. The patient has been under observation for 12 months and has shown no recurrence.  相似文献   
107.
Background and Aims: The purpose of this study was to investigate possible factors that could impact on γδ T cell accumulation in the gastric mucosa. Method: Subjects were 22 Helicobacter pylori (H. pylori)free and 75 H. pylori‐infected mucosa biopsies classified into grades I~III gastritis as per our previous study. The number of γδ‐ and 45 RO‐positive T cells were determined by immunostaining. Gastric mucosal anti‐H. pylori urease specific antibodies and interleukin (IL)‐1β, IL‐2, 4, 7, 10 and IL‐12 levels were assayed by enzyme‐linked immunosorbent assay (ELISA). CC chemokine receptor 2 (CCR2) expression levels, migration, and cytokine production in γδ T cells stimulated by H. pylori urease were also evaluated. Results: The γδ T cell count was significantly higher in grade III gastritis which exhibits strong immunoglobulin (Ig)A and IgG responses to H. pylori urease with lymphoid follicles than in other groups. γδ T cell count was significantly correlated with IL‐1β and interleukin‐7 (IL‐7) levels in the gastric mucosa. H. pylori urease immunoreactivity was detected in lamina propria of grade III gastritis, along with many γδ T cells. After H. pylori eradication therapy, the γδ T cell count in grade III gastritis significantly decreased. H. pylori urease stimulated significant increases in CCR2 expression levels, although to a lesser degree than those induced by IL‐7 stimulation in both peripheral and mucosal γδ T cells. Interferon (IFN)‐γ and IL‐10 production was also stimulated by H. pylori urease in peripheral γδ T cells. Conclusions: Gastric mucosal increases in IL‐7 and IL‐1β closely corresponded to the accumulation of γδ T cells in gastric mucosa. An association was also seen between γδ T cell accumulation and H. pylori urease‐specific Ig levels.  相似文献   
108.
Abstract Wrist activity rhythm and sleep diary data in a case of delayed sleep phase syndrome were investigated. The sleep self-estimation was nearly compatible with the activity levels of the actigraph. The actigraphic data were also analyzed. The subject's most fixed period of activity was 24.31 h, and acrophase (time of day) that fixed the data to a 24 h period was 03.25 h. The subject has had reversed night and day sleep patterns for more than 7 years. It was very difficult to advance the sleep phase when the delayed phase has been continuous long-term under the state of poor social cues.  相似文献   
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