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排序方式: 共有9100条查询结果,搜索用时 0 毫秒
1.
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
2.
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
3.
To clarify when and how rapidly individual muscles are damaged in the course of Duchenne muscular dystrophy (DMD), we followed X-ray CT of whole body skeletal muscles from 29 cases of DMD patients (age ranging 3 to 23 years) for a period of 2 to 6 years. Each patient had 2 to 5 scans with an average of 3.3. We evaluated chronological changes of 23 muscles from the entire body using the muscle damage stage defined as follows. The stages were classified into the following 5 stages: stage 0; normal, 1; area of fatty replacement less than 10% of whole muscle area, 2; area of fatty replacement between 10 to 50%, 3; area of fatty replacement 50 to 90%, 4; almost complete fatty replacement. Each muscle had its own period of rapid degeneration starting at 5 to 10 years of age and, continuing 5 to 10 years. In some muscles such as gluteus maximus or quadriceps femoris, fatty replacement started at 5 years or earlier and progressed for five years, while other muscles such as splenius capitis, damage started much later, e.g. around 10 years of age and the progression was much slower. There was a variation of at least 5 years among individual patients in any muscle damage stage, reflecting the variability of clinical severity in each patient. On the basis of the above results we defined the whole body muscle damage index as a summation of the muscle damage stages of the following five muscles: gluteus maximus, quadriceps femoris, gracilis, medial head of gastrocnemius and splenius capitis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
M Kurimoto N Hayashi H Kamiyama S Nagai T Shibata T Asahi N Matsumura Y Hirashima S Endo 《Minimally invasive neurosurgery》2004,47(5):278-283
Neuronavigation has become an effective therapeutic modality and is used routinely for intra-axial tumor removal. This retrospective study was conducted to evaluate the clinical impact of neuronavigation and image-guided extensive resection for adult patients with supratentorial malignant astrocytomas. Between 1990 and 2002, 76 adult patients with pathologically confirmed malignant astrocytomas underwent craniotomy and removal of the tumors at the Toyama Medical and Pharmaceutical University Hospital. Of these 76 patients, 42 were treated using neuronavigation with conventional microneurosurgery and the other 34 were treated with conventional microneurosurgery alone. Postoperative early MRI with contrast enhancement was done, and gross total resection was defined as the complete absence of residual tumor. Survival time was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from the Cox proportional hazards model. In univariate analysis, age (< 65), grade 3, preoperative KPS (>/= 80), use of neuronavigation, and gross total resection were significantly associated with longer survival. However, when the data were submitted to multivariate analysis, grade 3, preoperative KPS (>/= 80), and gross total resection were independent prognostic factors. The median survival periods of patients receiving gross total resection (vs. partial resection) and neuronavigation (vs. no neuronavigation) were 16 (vs. 9) months and 16 (vs. 10) months, respectively. The percentage of a gross total resection was significantly higher in the neuronavigation group compared to that in the no-navigation group (64.3 % vs. 38.2 %, p < 0.05). Neurological deterioration occurred in 4 of 42 (9.5 %) and in 6 of 34 (17.6 %) patients after surgery with neuronavigation and surgery without neuronavigation, respectively, although this difference was not statistically significant. Our results showed that neuronavigation increases the radicality in the resection of malignant astrocytomas and is objectively useful for improving survival time. 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
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Magnetic resonance imaging of 31 meningiomas in 29 patients was retrospectively reviewed and compared with pathologic specimens in 25 tumors to investigate how magnetic resonance imaging could delineate a tumor-brain interface. The thick, collagenous connective tissue, which was seen around four tumors, was shown as a low signal intensity rim on both a T1-weighted image and a T2-weighted image. A rim of low signal intensity on a T1-weighted image and high signal intensity on a T2-weighted image most likely represented cerebrospinal fluid space: this finding was seen around eight tumors. No distinct rim could be identified in five tumors. Of these five, two tumors grew invasively into the brain. Although mixed features predominated in meningiomas, magnetic resonance imaging could well delineate a tumor-brain relationship in most of the cases. 相似文献
10.
Yukata Okita M.D. Shigehito Miki M.D. Yuichi Ueda M.D. Takafumi Tahata M.D. Tetsuro Sakai M.D. Katsuhiko Matsuyama M.D. Masahiko Matsumura M.D. 《Journal of cardiac surgery》1994,9(4):433-439
A 6-year-old boy was successfully operated on for double outlet ventricle, common atrioventricular canal with severe valvular regurgitation, right atrial Isomerism, L-loop ventricles, total anomalous pulmonary venous connection, and pulmonary stenosis with hypoplastic left pulmonary artery. The Interventricular rerouting from the left ventricle to the ascending aorta was performed with a spiral patch, the lnteratrlal switching was performed by a Mustard patch, the common atrioventricular orifice was partitioned and valve repair was performed, and an 18-mm valved conduit was inserted between the right ventricle and the pulmonary artery. Although the patient had a small residual ventricular septal defect and pulmonary stenosls, the patient Is alive and well. 相似文献