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Abstract –  Although mouthguards have been suggested as a means for preventing dental traumatic injuries, there are still some controversies over some aspects such as effectiveness in preventing concussions, material selections, method for fabrication, design, side effects and so on. The purpose of this literature review was to clarify differences in opinions with supporting evidence on these issues and find the best guidelines for promoting usage and providing mouthguards with better protective capability and fewer side effects such as difficulty in breathing and speaking.  相似文献   
94.
We report a 64-year-old woman with follicular thyroid cancer found by subacute bulbar palsy. Progressive bulbar palsy (PBP) was considered the most likely diagnosis, because no abnormal finding was detected on brain CT and blood test except for the decrease of free T4. An echogram of the thyroid revealed a small nodule which was shown to be class IIb by fine needle biopsy. However, 201Tl scintillation examination showed skull base metastasis. Follicular thyroid cancer sometimes seems to manifest as a distant metastasis with no clinically evident thyroid lesion. This case suggested the importance of a detailed survey for malignancy, when subacute bulbar palsy is seen.  相似文献   
95.
A 47-year-old Japanese woman in whom obstructive jaundice had already been diagnosed, was found to have a dome-shaped elevated tumor approximately 3 cm in diameter located in the area very close to the papilla of Vater on endoscopical and radiographical investigations. Histopathologically, the resected tumor was composed mainly of solid nests of atypical argyrophilic cells, and partially of an area of well differentiated tubular adenocarcinoma, showing mutual transition in the mucosal layer. Both immunohistochemical and ultrastructural analyses confirmed the difference in character of tumor cells between these two areas: neuroendocrine cell carcinoma and tubular adenocarcinoma of common type in the intestine. To the best of our knowledge, this is only the third case reported to be a coexisting malignant carcinoid tumor and adenocarcinoma arising in the periampullary region.  相似文献   
96.
BACKGROUND: Concentration of carcinoembryonic antigen (CEA) is known as a marker of malignant transformation and chronic inflammation. We recently observed increased levels of serum CEA in a patient with asthma accompanied by mucoid impactions, which dramatically decreased after a sequence of bronchial washings. The present study evaluated relationships between levels of CEA, bronchial asthma and mucoid impactions. METHODS: Serum CEA concentrations were determined by chemiluminescent immunoassay (CLIA) or enzyme immunoassay in 44 subjects, comprising 9 asthmatic patients with mucoid impactions, 13 asthmatic patients without mucoid impactions, 12 patients with bronchiectasis, and 10 healthy volunteers. CEA concentrations in bronchoalveolar lavage fluid (BALF) were determined in 5 asthmatic patients with mucoid impactions and 10 healthy volunteers. RESULTS: Serum concentrations of CEA were significantly increased in asthmatic patients with mucoid impactions compared with patients without mucoid impactions, patients with bronchiectasis, or healthy volunteers (median [range], 17.3 ng/ml [2.8-28.8 ng/ml]; 3.0 ng/ml [1.5-7.1 ng/ml], 2.2 ng/ml [0.9-17.9 ng/ml], and 1.9 ng/ml [0.6-2.9 ng/ml], respectively). Concentrations of CEA in BALF were also significantly increased in asthmatic patients with mucoid impactions compared to healthy volunteers (3.2 ng/ml albumin [1.2-12.4 ng/ml albumin] vs. 0.4 ng/ml albumin [0.2-1.9 ng/ml albumin]). CONCLUSION: These findings suggest that bronchial asthma with mucoid impactions is among several pathogeneses that cause increased levels of CEA in serum and BALF.  相似文献   
97.
Pseudohypoparathyroidism type Ia (PHP-Ia), one of 4 types of PHP, is a genetic disease characterized by clinical hypoparathyroidism caused by parathyroid hormone (PTH) resistance. In addition, patients with PHP-Ia show resistance to other hormones as well as Albright's hereditary osteodystrophy (AHO), a constellation of features including short stature, obesity, brachydactyly, ectopic ossifications, and/or mental retardation. Hypocalcemia is one of the hallmarks of PHP-Ia, but several PHP-Ia patients have been described to have normocalcemia. We encountered a 10-year-old girl with typical Albright's hereditary osteodystrophy with round face, short stature, brachydactyly, and obesity. Biochemical examination showed normocalcemia and increased PTH levels. Ellsworth-Howard test did not show any responses of urinary cAMP and phosphate. Based on these findings, she was diagnosed as having PHP-Ia with normocalcemia. Sequencing analysis of the GNAS gene identified a heterozygous missense mutation in exon 13 (R385H), which was previously reported in a PHP-Ia patient. The exact reason for her normocalcemia is not determined, but we must recognize heterogeneous biochemical findings even in PHP-Ia.  相似文献   
98.
BACKGROUND: Cardiac sarcoidosis is frequently overlooked or misdiagnosed as idiopathic dilated cardiomyopathy (DCM), primarily because of difficulties in its diagnosis. This is a crucial issue because appropriate therapy with immunosuppressive agents can be initiated if early diagnosis is achieved. METHODS AND RESULTS: Thoracic computed tomography (CT) was retrospectively analyzed in detail with special reference to lymph node swelling (LNS) in the mediastinum of 8 patients diagnosed with idiopathic DCM who underwent left ventriculoplasty (LVP), and were later proven to have active cardiac sarcoidosis by histological evaluation of the resected myocardium. Twenty age-matched patients with idiopathic DCM who also underwent LVP served as controls. On conventional chest radiographs, none of the cardiac sarcoidosis patients exhibited lymph node involvement, including bilateral hilar lymphadenopathy. However, CT demonstrated significant mediastinal LNS in 7 (88%) of them and in only 1 (5%) of the 20 controls. There was a significant difference in the incidence of LNS in the 2 groups (p=0.00005). CONCLUSION: Evaluation of mediastinal lymphadenopathy by CT is an easy and valuable initial screening method for distinguishing cardiac sarcoidosis from idiopathic DCM.  相似文献   
99.
After the release of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines in 2001 and update in 2003, its implementation in nine Asian countries was investigated. Questionnaire surveys involving thoraco-pulmonary physicians or internists investigated the awareness and consensus of the GOLD guidelines including the care and management of chronic obstructive pulmonary disease (COPD) patients in Asian. Two surveys were conducted, in June 2002 and March 2004, through questionnaires by direct mail in Japan and face-to-face interviews in the other countries. Approximately 600 questionnaires were returned with approximately 84% awareness of the publication and its update and nearly 90% appreciated the globalization efforts. The survey revealed great variances concerning the definition of COPD, its diagnosis, and use of computed tomography. As for the implementation, the majority answered the use of the combined local and GOLD guidelines in five of nine countries surveyed, while the GOLD guidelines were implemented mainly in Korea, suggesting the influence in daily practice for care and management of COPD patients. Implication of rehabilitation in clinical practice has not been standardized despite high evidence of its advantages. Most respondents stated the necessity of developing a local or regional guideline for best practice. Our survey revealed: (i) awareness of the GOLD guidelines was high and well accepted; (ii) the possibility of developing a uniform or standard guideline in Asia is low due to local characteristics; (iii) modifications of the GOLD guidelines may be more practical; and (iv) that the multidisciplinary pulmonary rehabilitation program needs to be further activated in GOLD implementation for the Asia–Pacific region.  相似文献   
100.
Neurological complications during the treatment of hematological malignancies have a wide range of causes. Treatment-related leukoencephalopathy has been recognized as a major complication of combined chemotherapy and radiotherapy for central nervous system (CNS) lymphoma, and can complicate the diagnosis of CNS infection. Herein, we present a patient with diffuse large B-cell lymphoma who developed herpes simplex encephalitis (HSE) and subsequent cytomegalovirus encephalitis after chemoradiotherapy for CNS relapse. Although cerebrospinal fluid examination (CSF) showed no significant pleocytosis, brain magnetic resonance imaging and polymerase chain reaction analysis of the CSF were useful in the diagnosis. With a review of the literature on the association between HSE and radiotherapy for CNS malignancies, our case suggests that an awareness of viral encephalitis is important in the differential diagnosis of acute neurologic disturbance during chemoradiotherapy for CNS lymphoma.  相似文献   
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