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61.
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
62.
Yukiko Maeda Nobuyuki Hizawa Yoshinobu Fukui Katsura Nagai Eiki Kikuchi Daisuke Takahashi Toshiyuki Harada Noriaki Suko Masaharu Nishimura 《Nihon Kokyūki Gakkai zasshi》2004,42(12):988-993
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
63.
Kaoru Otsuka Fumio Terasaki Yoshinobu Eishi Hiroaki Shimomura Yasuharu Ogura Taiko Horii Tadashi Isomura Hisayoshi Suma Yasushi Kitaura 《Circulation journal》2007,71(12):1937-1941
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
64.
Yuzo Kodama Kuniaki Seyama Kaku Yoshimi June Ueki Hideichi Oka Yoshinobu Ikari Yoshinosuke Fukuchi 《Geriatrics & Gerontology International》2007,7(2):174-183
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
65.
Suzuki HI Hangaishi A Hosoya N Watanabe T Kanda Y Motokura T Chiba S Kurokawa M 《International journal of hematology》2008,87(5):538-541
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
66.
Saito Y Guo YM Hirokawa M Saito K Komatsuda A Takahashi N Fujishima M Fujishima N Yamashita J Sawada K 《International journal of hematology》2008,88(1):64-72
Tumor necrosis factor-alpha (TNF-alpha) has been shown to induce the differentiation of CD34(+) cells toward dendritic cells (DCs). We have previously shown that DCs are co-generated from human CD34(+) cells during erythroid or megakaryocytic differentiation in the presence of TNF-alpha, and those DCs are able to stimulate autologous T cell proliferation. The aim of this study was to learn whether the co-stimulation of granulocyte colony-stimulating factor (G-CSF) and TNF-alpha would generate neutrophil progenitors and DCs together from human CD34(+) cells, and if this was the case, to clarify the phenotypic and functional characteristics of these DCs. When highly purified human CD34(+) cells were cultured for 7 days with G-CSF alone, the generated cells predominantly expressed a granulocyte marker, CD15, and then differentiated into neutrophils after 14 days of culture. The addition of TNF-alpha with G-CSF markedly decreased the number of CD15(+) cells without affecting the total number of cells during 7 days of culture. Almost one third of the generated cells were positive for CD11c and CD123. Furthermore, CD11c(+) cells were found to phagocytose CD15(+) cells and were able to induce allogeneic, but not autologous, T cell proliferation in the mixed lymphocyte reaction (MLR). On the other hand, the CD11c(+) cells generated by TNF-alpha and cytokines capable of inducing erythroid differentiation were able to stimulate autologous T cells. There was a difference in the expression of CD80, CD83 and CD86 among CD11c(+) cells induced by G-CSF plus TNF-alpha and those generated by interleukin-3, stem cell factor, and erythropoietin plus TNF-alpha. These results indicate that the co-stimulation of human CD34(+) cells with G-CSF and TNF-alpha induces the phagocytosis of co-developing neutrophil progenitors by DCs, and the stimulatory effects of these DCs on autologous T cells is different from that of DCs generated from CD34(+) cells during erythroid differentiation. 相似文献
67.
Kojima H Uemura M Sakurai S Ann T Ishii Y Imazu H Yoshikawa M Ichijima K Fukui H 《Journal of gastroenterology》2002,37(8):617-625
Background:
Background: Liver disturbance in rheumatoid diseases results not only from liver disease associated with the rheumatoid diseases themselves
but also from various other causes. This study aimed to elucidate the clinical features of liver disturbance in rheumatoid
diseases, focusing on the cause of this disturbance.
Methods: A clinicopathological study was performed in 306 patients (106 with systemic lupus erythematosus, 71 with Sj?gren's syndrome,
59 with rheumatoid arthritis, 27 with scleroderma, 30 with polymyositis, and 13 with polyarteritis nodosa).
Results: Liver disturbance occurred in 43% of these patients and resulted from various causes. Its degree and duration varied from
one cause to another. Liver disease associated with rheumatoid diseases was the leading cause of the liver disturbance in
these patients and was characterized by mild and transient liver disturbance (maximum alanine aminotransferase [ALT] level
during the study period, 68 ± 8 IU/ml; maximum alkaline phosphatase [ALP] level, 410 ± 31 IU/ml; duration of liver disturbance,
6 ± 2 months). Most patients with this type of liver disease showed minimal change in liver histology, although two-thirds
of those evaluated by the international scoring system for autoimmune hepatitis (AIH) were classified as “probable” or “definite”.
Eight of 14 patients with histologically proven chronic hepatitis or cirrhosis were infected with hepatotropic virus (7 with
hepatitis C virus [HCV] and 1 with hepatitis B virus [HBV]). Five of 9 patients in whom the hepatic lesion progressed had
hepatotropic virus infection (4 with HCV and 1 with HBV), and the other 4 patients suffered from autoimmune liver diseases.
Conclusions: Liver disease associated with rheumatoid diseases was the leading cause of liver disturbance in these patients and was characterized
by mild and transient liver disturbance, whereas progressive liver diseases were often associated with hepatotropic virus,
mainly HCV, or autoimmune liver diseases. Liver histology is indispensable for differentiating AIH from liver disease associated
with rheumatoid diseases.
Received: August 27, 2001 / Accepted: January 7, 2002 相似文献
68.
69.
L J Yang C B Zeller N L Shaper M Kiso A Hasegawa R E Shapiro R L Schnaar 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(2):814-818
Nerve cells depend on specific interactions with glial cells for proper function. Myelinating glial cells are thought to associate with neuronal axons, in part, via the cell-surface adhesion protein, myelin-associated glycoprotein (MAG). MAG is also thought to be a major inhibitor of neurite outgrowth (axon regeneration) in the adult central nervous system. Primary structure and in vitro function place MAG in an immunoglobulin-related family of sialic acid-binding lactins. We report that a limited set of structurally related gangliosides, known to be expressed on myelinated neurons in vivo, are ligands for MAG. When major brain gangliosides were adsorbed as artificial membranes on plastic microwells, only GT1b and GD1a supported cell adhesion of MAG-transfected COS-1 cells. Furthermore, a quantitatively minor ganglioside expressed on cholinergic neurons, GQ1b alpha (also known as Chol-1 alpha-b), was much more potent than GT1b or GD1a in supporting MAG-mediated cell adhesion. Adhesion to either GT1b or GQ1b alpha was abolished by pretreatment of the adsorbed gangliosides with neuraminidase. On the basis of structure-function studies of 19 test glycosphingolipids, an alpha 2,3-N-acetylneuraminic acid residue on the terminal galactose of a gangliotetraose core is necessary for MAG binding, and additional sialic acid residues linked to the other neutral core saccharides [Gal(II) and GalNAc(III)] contribute significantly to binding affinity. MAG-mediated adhesion to gangliosides was blocked by pretreatment of the MAG-transfected COS-1 cells with anti-MAG monoclonal antibody 513, which is known to inhibit oligodendrocyte-neuron binding. These data are consistent with the conclusion that MAG-mediated cell-cell interactions involve MAG-ganglioside recognition and binding. 相似文献
70.
Shinobu Osanai Toru Takahashi Hiroyuki Enomoto Nobuyuki Satoh Osamu Yahara Yuji Akiba Satoru Fujiuchi Hitoshi Nakano Yoshinobu Ohsaki and Kenjiro Kikuchi 《Respirology (Carlton, Vic.)》2001,6(2):163-166
We describe a case of a 21-year-old man with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) who presented with hypoxic ventilatory depression. He had chronic hypoventilation, which was not explained by weakness of respiratory muscles. His hypercapnic ventilatory response was not impaired. In contrast, hypoxic ventilatory depression was observed in the isocapnic progressive hypoxic response test. After exposure to hypoxic conditions, his respiratory frequency decreased and tidal volume was unchanged. The hypoxic ventilatory depression was partially blocked by pretreatment with aminophylline. In conclusion, we need to be careful with patients with MELAS who are hypoxaemic because a vicious circle of hypoxia and hypoventilation can occur. 相似文献