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排序方式: 共有1125条查询结果,搜索用时 968 毫秒
71.
Takagi Y Sumi M Van Cauteren M Nakamura T 《Journal of magnetic resonance imaging : JMRI》2005,22(1):29-37
PURPOSE: To establish a fast and high-resolution MR sialographic technique that provides fast and high-resolution imaging. MATERIALS AND METHODS: MR sialography was performed on a 1.5-T MR imager using a small (47-mm) surface coil. We determined appropriate sequence parameters, and then applied the technique to the salivary glands of 143 patients with xerostomia (including those with Sj?gren's syndrome or hyperlipidemia) or salivary gland inflammation. We compared the high-resolution MR sialography with conventional x-ray sialography in the patients with xerostomia to evaluate the effectiveness of the MR sialography technique. RESULTS: We found that a single-shot, single-slice MR sialography (TR/TR/number of signal acquisitions [NSA] = 8000 msec/1000 msec/6) using a small surface coil provides excellent duct images that are clinically feasible with fast (imaging time of 56 seconds) and high-resolution images. An alternative three-dimensional MR sialography technique provided better details of the branches at the expense of imaging time. The MR sialography technique using a small surface coil depicted effectively the ductal changes in the salivary glands in patients with or without Sj?gren's syndrome, reflecting the severity of the diseases. CONCLUSION: We conclude that MR sialography can be performed using a fast and high-resolution sequence. 相似文献
72.
73.
Sato Y Tamaki J Kitayama F Kusaka Y Kodera Y Koutani A Iki M 《The Tohoku journal of experimental medicine》2005,207(3):217-222
Assessing calcium intake is necessary for epidemiological studies on osteoporosis. This study was aimed at developing a valid food frequency questionnaire (FFQ) to estimate the dietary calcium intake of Japanese people. The FFQ contains 26 items, representing common sources of calcium. The respondents, 74 women aged 15 - 79 years living in Fukui city, whose dietary calcium intake was estimated at 638 +/- 306 (S.D.) mg based on a one-day weighted food record kept during the National Nutrition Survey of 1996, were asked to indicate their consumption frequency and usual portion size (large, medium, small) for each food item. Trained dieticians interviewed the subjects to confirm their answers to the FFQs. The mean calcium intake per day according to the FFQ (655 +/- 222 mg) did not differ significantly from that according to the one-day food record. The coefficient of correlation between these methods was 0.512, a statistically significant value. The calcium intake from dairy products showed a good correlation, r = 0.717. The coefficient of correlation between the values estimated based on two FFQ filled out three days apart was 0.900, showing good test-retest reliability. Therefore, this FFQ is valid and reliable in estimating dietary calcium intake for epidemiological studies. 相似文献
74.
Fukuda T Yamashita Y Nagamitsu S Miyamoto K Jin JJ Ohmori I Ohtsuka Y Kuwajima K Endo S Iwai T Yamagata H Tabara Y Miki T Matsuishi T Kondo I 《Brain & development》2005,27(3):211-217
A total of 45 different mutations of methyl-CpG-binding protein 2 gene (MECP2) were identified in 145 of 219 Japanese patients with typical or atypical Rett syndrome (RTT) (66.2%). A missense mutation, T158M was the most common mutation of MECP2, identified in 22 (19.1%) patients, followed by four nonsense mutations, R168X (14.8%), R270X (13.0%), R255X (9.6%), and R294X (6.1%) in 115 patients with classical RTT. Two missense mutations, R133C (33.3%) and R306C (23.3%), and a nonsense mutation, R294X (13.3%), were common in 30 patients with atypical RTT, including the preserved speech variant (PSV). Frameshift mutations due to nucleotide deletion or insertion were identified in 22 patients with MECP2 mutations, and one of them had a 3.6 kb deletion encompassing exons 3 and 4. Three patients with classical RTT had a splicing anomaly. The wide spectrum of phenotypic variability in patients with RTT has been considered to be correlated with the mutation type and location in MECP2, and X-inactivation. However, most patients showed a random X-inactivation pattern evaluated by an androgen receptor gene polymorphism in this study, suggesting that a skewed X-inactivation might not be a main modification factor on clinical phenotypes of RTT. In addition, three new missense mutations, P176R, A378V and T479M, were identified in patients with RTT, but also in healthy Japanese, indicating that these mutations are non-pathogenic in Japanese. Information about rare polymorphic variations is very important for the molecular diagnosis of RTT, although rare polymorphic variants might differ among ethnic groups. 相似文献
75.
Takagi Y Sumi M Sumi T Ichikawa Y Nakamura T 《AJNR. American journal of neuroradiology》2005,26(5):1207-1214
BACKGROUND AND PURPOSE: MR imaging of the salivary glands has been applied to the diagnosis of Sjogren's syndrome; however, the diagnosis remains qualitative. We sought to establish and evaluate quantitative MR imaging criteria for the diagnosis of Sjogren's syndrome. METHODS: MR imaging with a 47-mm microscopy coil was performed in 83 patients with xerostomia (55 patients with Sjogren's syndrome, 28 without Sjogren's syndrome). MR images were obtained by T1-weighted and fat-suppressed T2-weighted imaging and by MR sialography of the parotid glands. MR imaging findings of the parotid glands in Sjogren's syndome included increases in fat areas and decreases in intact lobule areas. These MR images were morphometrically analyzed for the diagnostic criteria. RESULTS: MR imaging with a microscopy coil demonstrated well the details of the damaged parotid glands in patients with xerostomia. Quantitative MR imaging of fat, intact gland lobule, and number of sialoectatic foci significantly and highly correlated with severity of disease. Receiver operating characteristic (ROC) curve analysis demonstrated that quantitative MR imaging yielded high diagnostic ability in differentiating patients with xerostomia who have Sjogren's syndrome from those without Sjogren's syndrome, with areas under the ROC curve of 0.94 for fat area, 0.98 for intact lobule area, and 0.91 for number of sialoectatic foci. The best cutoff points by quantitative MR imaging were each associated with high sensitivity and specificity, and, when used in combination, yielded 96% sensitivity and 100% specificity. CONCLUSION: Quantitative MR imaging effectively differentiated the parotid glands in patients with xerostomia who have Sjogren's syndrome from those without the syndrome and provided criteria for staging the gland disease. 相似文献
76.
Sata N Moriyama Y Hamada N Horinouchi T Miyahara K 《The Annals of thoracic surgery》2004,78(4):1472-1475
We encountered a 72-year-old woman with a left atrial hemangioma arising in the appendage and growing like an extracardiac mass. Life-threatening cardiac tamponade, recurrent over a 5-year clinical course, was the only sign of this rare tumor. The extraatrial growth pattern of the tumor made it difficult to distinguish the cardiac origin from a paracardiac mass. With the aid of cardiopulmonary bypass, the tumor was removed from the left atrium at the base of the appendage. Pathologic diagnosis was a combination of cavernous- and venous-type hemangioma. The postoperative course was uneventful, and the patient was doing well with no pericardial effusion at the 10-month follow-up. 相似文献
77.
Wallerian degeneration of the middle cerebellar peduncle after pontine infarction: MR imaging 总被引:5,自引:0,他引:5
PURPOSE: To report magnetic resonance (MR) imaging findings of wallerian degeneration of the pontocerebellar tract secondary to a pontine infarction. MATERIALS AND METHODS: We retrospectively reviewed cranial MR images obtained during the past seven years in our institution and selected those from patients with a chronic stage of pontine infarction and a hyperintense lesion at the central portion of the middle cerebellar peduncle on T2-weighted images. RESULTS: In three patients with a ventromedial pontine infarction, we found a symmetrical hyperintense lesion at the central portion of the middle cerebellar peduncle bilaterally on T2-weighted MR images in the chronic stage. In another patient with a ventrolateral pontine infarction, we found such a lesion at the ipsilateral middle cerebellar peduncle. CONCLUSION: Because the middle cerebellar peduncle carries afferent fibers from the contralateral basis pontis to the cerebellar cortex, these middle cerebellar peduncular lesions are regarded as wallerian degeneration. This secondary degeneration should not be misinterpreted as a newly developed infarction or other disease. 相似文献
78.
Adachi T Koeda T Hirabayashi S Maeoka Y Shiota M Wright EC Wada A 《Brain & development》2004,26(5):301-306
It is sometimes difficult to discriminate high functioning pervasive developmental disorders (HFPDD) from attention deficit/hyperactivity disorders (AD/HD) in young children because of the behavioral similarities between the two. For adequate diagnosis, understanding fundamental differences in their social cognitive abilities might become significant. In order to detect the differences in social cognitive abilities between AD/HD and HFPDD, a new test, the Metaphor and Sarcasm Scenario Test (MSST) was developed. One hundred and ninety-nine normal school children (the control group), 29 AD/HD children and 54 HFPDD children were involved. The results showed that the inability to understand a sarcastic situation was specific to children with HFPDD, both children with AD/HD and HFPDD could not equally understand metaphor. The correlation between the comprehension of sarcasm and success in the theory of mind task was remarkably high but not for comprehension of metaphor. In conclusion, the MSST has the potential to discriminate HFPDD from AD/HD in young children. 相似文献
79.
Systemic or intra-striatal administration of d-amphetamine (AMPH) elicits a dose-dependent pattern of behavioral activation and neuronal firing in the striatum. To determine if the AMPH-induced striatal firing pattern is expressed in the substantia nigra pars reticulata (SNr), a main target of striatal efferents and the primary output nucleus of the basal ganglia, we recorded the activity of 214 SNr units in alert, behaving rats responding to either systemic (1.0 or 5.0 mg/kg, sc) or intra-striatal (20 microg/microl/min) AMPH. Both routes of administration increased behavior but the strongest effects occurred after systemic injection. A dose of 1.0 mg/kg progressively increased locomotion, head movements, and sniffing, whereas after 5.0 mg/kg behavioral responding became progressively more focused and stereotyped. The collective response of SNr neurons was a net increase in firing rate that was most apparent after the low systemic dose and intra-striatal infusion. Further analysis revealed significant unit populations that were either excited, inhibited or showed no change. Although excitations predominated over inhibitions in all cases, a sizable population of units was unresponsive: approximately 25% to systemic AMPH and almost half to intra-striatal infusion. Subsequent injection of haloperidol (0.5 or 1.0 mg/kg, sc), a dopamine receptor antagonist, reversed both the behavioral and electrophysiological effects of AMPH. Thus, as in striatum, dopamine appears to play a critical role in AMPH-induced changes in SNr activity. Interestingly, however, SNr activity did not closely parallel the striatal response, suggesting that patterns of neuronal responding to AMPH in striatum are not reliably relayed to SNr. 相似文献
80.
Ikoma N Matsuyama T Nuruki H Iizuka M Umezawa Y Ohta Y Ozawa A Sekido Y Shimamura K Ueyama Y 《The Tokai journal of experimental and clinical medicine》2004,29(2):49-51
A case of atypical benign fibrous histiocytoma is reported. A 62-year-old Japanese female visited our clinic because of an asymptomatic solitary lesion on the skin of the left leg. Physical examination revealed a polypoid mass lesion (2.5 x 2.3 x 1.8 cm) with central erosion. The lesion began with a 1 mm-sized papule and slowly enlarged over the 20 years. Clinical diagnosis was a malignant tumor such as dermatofibrosarcoma protuberans, atypical fibroxanthoma or adnexal tumors. Biopsy of the polypoid lesion was carried out. Histopathological examination revealed a polypoid lesion consisting of proliferation of fibroblast-like spindle cells in the dermis. Large atypical cells with pleomorphic nuclei were occasionally observed but mitotic figures were rare. From immunohistochemical results (CD68, Factor-XIII, MIB-1 labeling index), we diagnosed this case as "atypical benign fibrous histiocytoma (ABFH)". Clear distinction has not been made between ABFH, a variant of benign fibrous histiocytoma, and atypical fibroxanthoma, which is a variant of malignant fibrous histiocytoma. Here we report a case of ABFH with a diagnosis of the neoplasm. 相似文献