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排序方式: 共有5560条查询结果,搜索用时 31 毫秒
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Shuichi Kuniyuki 《The Journal of dermatology》1997,24(2):120-124
A 50-year-old Japanese man had a blue-black patch on the dorsum of his right wrist. Light and electron microscopic study of the lesion revealed dermal melanocytes containing mature melanosomes, predominantly in the upper dermis. This case was diagnosed as acquired dermal melanocytosis confined to the right wrist. 相似文献
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Shuichi Sato Fumiko Nasu Katsutoshi Motegi 《Journal of oral and maxillofacial surgery》2002,60(8):867-872
PURPOSE: The purpose of this study was to examine changes of chewing movement and masticatory efficiency during the natural course of nonreducing disc displacement of the temporomandibular joint (TMJ). PATIENTS AND METHODS: The subjects were 15 patients who had been diagnosed with nonreducing disc displacement of the TMJ but had received no treatment. Chewing movement and masticatory efficiency were examined at the initial visit and at a mean follow-up of 21.7 months, using mandibular kinesiography and adenosine triphosphate ebteric-coated granules. As a control, 23 persons who had no current or previous TMJ symptoms were studied. RESULTS: The patients' clinical signs and symptoms tended to be alleviated during the follow-up period. In normal controls, chewing movement showed lateral excursion to the chewing side on both the right and left sides. In patients, chewing movement at the initial visit showed lateral excursion to the chewing side during chewing on the TMJ affected side, but no such deviation was noted during chewing on the TMJ unaffected side in the horizontal plane. However, chewing movement at follow-up became similar to that of controls. In patients, masticatory efficiency became better during the natural course, although that at follow-up did not always reach the control's level. CONCLUSION: In untreated patients with nonreducing disc displacement of the TMJ, chewing movement and masticatory efficiency tend to improve spontaneously. 相似文献
5.
Hiromitsu Nakaya Shuichi Kawashiri Akira Tanaka Natsuyo Noguchi Koroku Kato Takashi Hase Etsuhide Yamamoto 《Journal of oral pathology & medicine》2005,34(2):87-92
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion. 相似文献
6.
Novel SCN5A mutation (Q55X) associated with age-dependent expression of Brugada syndrome presenting as neurally mediated syncope. 总被引:1,自引:0,他引:1
BACKGROUND: An association between Brugada syndrome and neurally mediated syncope has been described. Although mutations in SCN5A have been identified in Brugada syndrome, the genetic link between Brugada syndrome and neurally mediated syncope has not been determined. OBJECTIVES: The purpose of the study was to clinically and genetically characterize a man with recurrent syncope that originally was diagnosed as neurally mediated syncope at age 8 years but subsequently manifested as Brugada syndrome at age 17 years. METHODS: The proband underwent clinical examination, which included head-up tilt test, sodium channel provocation test, and electrophysiologic study. Genetic screening of SCN5A was performed for the proband and his family members. The biophysical properties of a mutant SCN5A channel in a heterologous expression system were studied using whole-cell, patch clamp technique. RESULTS: The proband showed positive head-up tilt test, coved-type ST elevation recorded from the third intercostal space, and positive pilsicainide provocation test. Ventricular fibrillation was inducible at programmed electrical stimulation, consistent with characteristics of both Brugada syndrome and neurally mediated syncope. A novel nonsense SCN5A mutation (Q55X) was identified in the proband, his mother, and his asymptomatic brother. The heterologously expressed mutant channel was nonfunctional. CONCLUSION: We genetically determined an SCN5A mutation in a patient showing the combined phenotype of neurally mediated syncope and Brugada syndrome. Neurally mediated syncope and Brugada syndrome may share, at least in part, a common pathophysiologic mechanism. 相似文献
7.
Masujiro Makita MD Futoshi Akiyama MD Naoya Gomi MD Takuji Iwase MD Fujio Kasumi MD Goi Sakamoto MD 《The breast journal》2006,12(S2):S210-S217
Abstract: To improve the utility of mammary ductoscopy, we investigated the correlation between endoscopic findings and histologic findings using intraductal biopsy specimens. Seventy-one intraductal biopsy specimens obtained from 63 patients between October 2001 and March 2004 were analyzed retrospectively. All specimens were obtained from monotonous intraductal lesions immediately after observation by mammary ductoscopy and were composed of a pure histologic subtype. With regard to endoscopic findings, color was classified as yellow, red, white, or colorless, and morphology was classified as spherical, lobular, mulberry, or amorphous. The histologic subtype was classified as papillotubular, papillary, degenerated, papillary cancer, solid-type ductal carcinoma in situ (DCIS), or cribriform cancer. The relationship between histologic diagnosis, color, and morphology was investigated. Intraductal biopsy specimens included 25 specimens of carcinoma and 46 specimens of papilloma. There was no significant correlation between color and diagnosis. Fourteen of 25 carcinoma specimens were amorphous, and amorphous morphology was significantly suggestive of malignancy (p < 0.001). Further, cribriform cancer was associated with amorphous morphology and yellow color. Morphology may be a useful endoscopically delineated parameter for differentiating intraductal lesions. 相似文献
8.
Hiroshi Uno Yoshihiro Izawa Kiyoshi Sagara Tamotsu Koyama Tokutaro Makita Chia-Yuan Hsu-Chang Mitsugi Sugiyama 《Journal of bone and mineral metabolism》1990,8(1):10-16
The effect of 1α-hydroxyvitamin D3 (1α(OH)D3) on the metabolic bone disorders developed in gastrectomized rats were investigated biochemically and histomorphologically.
1α(OH)D3 was suspended in 0.2 % Triton-X-100 aqueous solution after dissolving in a very small amount of ethanol, was given orally
to the rats for 10 weeks. The sham operated animals and the gastrectomy control animals received the vehicle alone. Gastrectomy
was followed by the development of the metabolic bone disorders after 10 weeks of observation. This was characterized by reduction
in ash content of the femur and histologically by a disappearance of the trabecular bone in tibial metaphysis. Decrease Ca
absorption from the intestines was demonstrated by a radiotracer technique. Biochemical studies showed significant decreases
in serum 25(OH)D concentration in gastrectomized rats. These findings suggest that gastrectomy partially impairs intestinal
absorption of calcium and results in a negative calcium balance, which may contribute to the development of bone metabolic
disorders in rats. The administration of 1α(OH)D3 increased dose-dependently serum calcium and Ca absorption from the intestine and prevented the development of bone metabolic
disorders histomorphologically. 相似文献
9.
10.
Comparison of p53 expression in proximal and distal gastric cancer: Histopathologic correlation and prognostic significance 总被引:2,自引:0,他引:2
Huihuan Tang MD Shuichi Hokita MD PhD Xiangming Che MD Masamichi Baba MD PhD Kuniaki Aridome MD PhD Fumio Kijima MD Gen Tanabe MD PhD Sonshin Takao MD PhD Dr. Takashi Aikou MD PhD 《Annals of surgical oncology》1997,4(6):470-474
Background: The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but
no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53
expression of proximal and distal gastric cancer concerning histopathology and prognosis.
Methods: A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical
methods.
Results: p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher
than in distal gastric cancer (38.8% vs. 20.0%, p<0.05). A 5-year survival analysis showed that there is no significant difference
between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology
of gastric cancer.
Conclusion: p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer. 相似文献