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71.
We determined whether hyperplastic mucosa adjacent to colon cancer contributes to neoplastic angiogenesis. Surgical specimens of human colon cancer (40 Dukes' stage B and 34 Dukes' stage C) were analyzed by immunohistochemistry for expression of proliferative and angiogenic molecules. The mucosa adjacent to Dukes' stage C tumors (but not Dukes' stage B tumors) had a higher Ki-67 labeling index and a higher expression of epidermal growth factor receptor and transforming growth factor-alpha than distant mucosa. The expression levels of vascular endothelial growth factor, basic fibroblast growth factor, interleukin-8, and the vascular density in the adjacent mucosa were similar to those in the tumor lesions and significantly higher than those in the distant mucosa. The expression of interferon-beta inversely correlated with the level of pro-angiogenic molecules and the vascular density. The injection of metastatic human colon cancer cells and murine colon cancer cells into the cecal wall of mice induced hyperplastic changes in the adjacent mucosa which expressed higher levels of epidermal growth factor receptor, basic fibroblast growth factor, and vascular endothelial growth factor, and lower levels of interferon-beta than did the control mucosa, which directly correlated with the degree of hyperplasia. These data suggest that metastatic human colon cancer cells can induce hyperplasia in the adjacent mucosa, which in turn produces angiogenic molecules that contribute to neoplastic angiogenesis.  相似文献   
72.
We present a case of granular cell tumor (GCT) occurring in the esophagus 7 years after operation for bronchial GCT. A 59-year-old Japanese man complained of epigastralgia, and endoscopic examination of the upper digestive tract disclosed a submucosal tumor in the lower esophagus. Histological examination of the endoscopic mucosal resection of the esophageal tumor showed a proliferation of neoplastic cells with an eosinophilic and granular cytoplasm. The cytoplasm of the neoplastic cells was histochemically positive for PAS stain and immunohistochemically positive for S-100. This tumor did not fulfill any of the diagnostic criteria for malignancy at either the macroscopic or microscopic level. I believe that this is the first case of GCT occurring metachronously in the respiratory and digestive tracts. Clinicians and pathologists should bear in mind that GCT may arise metachronously in the respiratory and digestive tracts.  相似文献   
73.

Purpose

The aim of this study was to evaluate anatomically the relationship between bone and muscles by detailed observation of the bone shape and the structure of muscles to facilitate an understanding of the function of the muscles involved in jaw movement.

Methods

36 specimens of 24 Japanese cadavers were examined. The insertion areas were marked using a radiopaque marker and examined by micro-computed tomography. For morphological observation, we used 101 condylar processes. In addition, we made histological sections in some specimens to observe the detailed attachments of the muscle.

Results

Based on the micro-CT images and dissection findings, the lateral pterygoid muscle was found to be most frequently inserted into the anterior impression and attached to the medial impression of the process. According to the histological observations, the lateral pterygoid muscle mainly inserted to the condylar process. The micro-CT images indicated that the obvious bony ridge was lateral to the pterygoid fovea on the condylar process in all specimens. The midmedial muscle bundle of the temporalis was attached to the ridge. Based on the morphological observations, the ridge was situated on the lateral area of the condylar process.

Conclusions

Since dysfunction of the temporomandibular joint is likely closely related to both the lateral pterygoid muscle and also the temporalis, further studies are necessary to evaluate the function of these muscles and consider jaw movement.
  相似文献   
74.
Camostat mesilate (CM), an oral protease inhibitor, has been used clinically for the treatment of chronic pancreatitis in Japan. However, the mechanism by which it operates has not been fully understood. Our aim was to evaluate the therapeutic efficacy of CM in the experimental pancreatic fibrosis model induced by dibutyltin dichloride (DBTC), and we also determined the effect of CM on isolated monocytes and panceatic stellate cells (PSCs). In vivo, chronic pancreatitis was induced in male Lewis rats by single administration of 7 mg/kg DBTC and a special diet containing 1 mg/g CM was fed to the DBTC+CM-treated group from day 7, while the DBTC-treated group rats were fed a standard diet. At days 0, 7, 14 and 28, the severity of pancreatitis and fibrosis was examined histologically and enzymologically in both groups. In vitro, monocytes were isolated from the spleen of a Lewis rat, and activated with lipopolysaccharide stimulation. Thereafter, the effect of CM on monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF-alpha) production from monocytes was examined. Subsequently, cultured rat PSCs were exposed to CM and tested to see whether their proliferation, MCP-1 production and procollagen alpha1 messenger RNA expression was influenced by CM. In vivo, the oral administration of CM inhibited inflammation, cytokines expression and fibrosis in the pancreas. The in vitro study revealed that CM inhibited both MCP-1 and TNF-alpha production from monocytes, and proliferation and MCP-1 production from PSCs. However, procollagen alpha1 expression in PSCs was not influenced by CM. These results suggest that CM attenuated DBTC-induced rat pancreatic fibrosis via inhibition of monocytes and PSCs activity.  相似文献   
75.
非侵入性腰椎屈伸运动的动态观察   总被引:2,自引:0,他引:2  
本研究应用电视X线动态摄影和计算机图形重建技术,建立了数字化X线电视分析系统,可对脊柱的总体和各活动节段作非侵入性动态观检。通过对44例正常人腰椎主动屈伸运动测定,取得一组正常参数值。并将本法试用于21例腰腿痛患者。结果表明:腰椎屈伸活动时,L1~2角活动度和平移量最小,分别为12.57°和2.1mm;L4~5角活动度和平移量最大,分别为18.42°和3.7mm。正常人腰椎各节段屈曲活动度和平移量比伸直活动时大,每5~6°屈伸活动伴有1mm平移。正常人男、女之间在屈伸活动时,各节段活动度和平移量无显著性差异(P>0.05);正常人各年龄组之间的活动度和平移量无显著性差异(P>0.05)。本法在精度、可重复性、无创伤性、可分节段性检测和可发现一些“潜在”运动学异常等方面具有独特优点,有较大的研究和临床应用价值。  相似文献   
76.
77.
We investigated the association between ulcerative colitis (UC) and polymorphisms of IL-17A (rs2275913, G-197A) and IL-17F (rs763780, 7488T/C) genes. We employed the multiplex PCR-SSCP method to detect gene polymorphisms. Both the numbers of -197A (IL-17A) and 7488T (IL-17F) alleles were significantly correlated to the development of UC. The frequencies of -197A/A and 7488T/T genotypes in the UC group were significantly higher than those in the non-UC group. An adjusted analysis revealed that -197A and 7488T alleles were independent risk factors for the developing UC. In addition, both polymorphisms were significantly associated with the pancolitis phenotype. Furthermore, -197A allele was significantly correlated to the chronic relapsing phenotype and -197A/A homozygote was more frequent in steroid-dependent cases, whereas 7488T allele was correlated with the chronic continuous phenotype. Our results provided the first evidence that -197A (IL-17A) and 7488T (IL-17F) alleles may influence the susceptibility to and pathophysiological features of UC independently.  相似文献   
78.
Mesh surgeries, such as sacrocolpopexy and transvaginal mesh surgery, are commonly used to treat pelvic organ prolapse. Although mesh surgeries have a high success rate, they are unsuitable for some patients. For a patient with pelvic organ prolapse and highly calcified multiple fibroids, we performed hybrid sacrocolpopexy combined with transvaginal mesh surgery with a method modified for the patient's condition. Three months after surgery, the results were highly satisfactory. This approach is simple, secure, and versatile for patients who are not good candidates for conventional mesh surgeries. This novel hybrid mesh surgery is an option for treating various types of pelvic organ prolapse.  相似文献   
79.
Genetic polymorphisms of the interleukin 28B (IL28B) locus are associated closely with outcomes of pegylated-interferon (PEG-IFN) plus ribavirin (RBV) combination therapy. The aim of this study was to investigate the relationship between IL28B polymorphism and responses to therapy in patients infected with genotype 2. One hundred twenty-nine chronic hepatitis C patients infected with genotype 2, 77 patients with genotype 2a and 52 patients with genotype 2b, were analyzed. Clinical and laboratory parameters, including genetic variation near the IL28B gene (rs8099917), were assessed. Drug adherence was monitored in each patient. Univariate and multivariate statistical analyses of these parameters and clinical responses were carried out. Univariate analyses showed that a sustained virological response was correlated significantly with IL28B polymorphism, as well as age, white blood cell and neutrophil counts, adherence to RBV, and rapid virological response. Subgroup analysis revealed that patients infected with genotype 2b achieved significantly lower rapid virological response rates than those with genotype 2a. Patients with the IL28B-major allele showed higher virus clearance rates at each time point than those with the IL28B-minor allele, and the differences were more profound in patients infected with genotype 2b than those with genotype 2a. Furthermore, both rapid and sustained virological responses were associated significantly with IL28B alleles in patients with genotype 2b. IL28B polymorphism was predictive of PEG-IFN plus RBV combination treatment outcomes in patients infected with genotype 2 and, especially, with genotype 2b. In conclusion, IL-28B polymorphism affects responses to PEG-IFN-based treatment in difficult-to-treat HCV patients.  相似文献   
80.
We report a case of Chlamydophila (C.) pneumoniae infection presenting with fever and rapid intrahepatic cholestasis. A 63-year-old man had a week-long history of intermittent high fever and rapidly progressive jaundice with atypical erythema. The results of liver function tests were recorded. The results of all serological tests were negative; the IgM, IgG, and IgA titers for C. pneumoniae had increased, which indicates a C. pneumoniae infection. The patient's fever and liver dysfunction improved upon administration of minocycline. Light microscopic findings showed the presence of enlarged liver cells with clear cytoplasm, a few mitotic figures, multinucleated cells, and bile cholestasis. The electron microscopic appearance of liver biopsy showed that bile canaliculi exhibited intrahepatic forms of cholestasis. From the results of light and electron microscopy, we inferred atypical intrahepatic cholestasis, probably resulting from the C. pneumoniae infection.  相似文献   
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