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排序方式: 共有6318条查询结果,搜索用时 245 毫秒
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Kosuke Kaida Masaya Takahashi Torbj?rn Akerstedt Akinori Nakata Yasumasa Otsuka Takashi Haratani Kenji Fukasawa 《Clinical neurophysiology》2006,117(7):1574-1581
OBJECTIVE: The Karolinska sleepiness scale (KSS) is frequently used for evaluating subjective sleepiness. The main aim of the present study was to investigate the validity and reliability of the KSS with electroencephalographic, behavioral and other subjective indicators of sleepiness. METHODS: Participants were 16 healthy females aged 33-43 (38.1+/-2.68) years. The experiment involved 8 measurement sessions per day for 3 consecutive days. Each session contained the psychomotor vigilance task (PVT), the Karolinska drowsiness test (KDT-EEG alpha & theta power), the alpha attenuation test (AAT-alpha power ratio open/closed eyes) and the KSS. RESULTS: Median reaction time, number of lapses, alpha and theta power density and the alpha attenuation coefficients (AAC) showed highly significant increase with increasing KSS. The same variables were also significantly correlated with KSS, with a mean value for lapses (r=0.56). CONCLUSIONS: The KSS was closely related to EEG and behavioral variables, indicating a high validity in measuring sleepiness. SIGNIFICANCE: KSS ratings may be a useful proxy for EEG or behavioral indicators of sleepiness. 相似文献
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Takako Miyamae Masaaki Mori Yasuji Inamo Youichi Kohno Shuji Takei Motoharu Maeda Takuji Murata Shuji Nakata Hiroshi Kawai Yukiko Hirano Yukiji Date Katsuhiko Kitamura Shumpei Yokota 《Ryūmachi》2003,43(3):538-543
OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children. 相似文献
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Clinical outcome of surgical management for patients with renal cell carcinoma involving the inferior vena cava 总被引:1,自引:0,他引:1
Tomoaki Terakawa Hideaki Miyake Atsushi Takenaka Isao Hara Masato Fujisawa 《International journal of urology》2007,14(9):781-784
BACKGROUND: The objective of this study was to evaluate the clinical outcome after surgical management of renal cell carcinoma (RCC) extending to the inferior vena cava (IVC). METHODS: This study included a total of 55 patients (41 men and 14 women; mean age, 59.3 years) with RCC (39 right- and 16 left-sided tumors) involving the IVC, who underwent radical nephrectomy and tumor thrombectomy between 1983 and 2005 at a single institution in Japan. The level of thrombus was classified as follows: level I, infrahepatic; level II, intrahepatic; level III, suprahepatic; and level IV, extending to the atrium. Clinicopathological data from these patients were retrospectively reviewed to identify factors associated with survival. RESULTS: There were 11 and 18 patients who were diagnosed as having lymph node and distant metastases, respectively. Twenty-two patients had tumor thrombus in level I, 20 in level II, 10 in level III, and 3 in level IV. Pathological examinations demonstrated that 34 and 21 patients had clear cell carcinoma and non-clear cell carcinoma, respectively, 42, 9 and 4 were pT3b, pT3c and pT4, respectively, and 6, 35 and 14 were Grades 1, 2 and 3, respectively. Cancer-specific 1-, 3- and 5-year survival rates of these 55 patients were 74.5%, 51.4% and 30.3%, respectively. Among several factors examined, clinical stage (P = 0.047), lymph node metastasis (P = 0.016), histological subtype (P = 0.034) and tumor grade (P < 0.001) were significantly associated with cancer-specific survival by univariate analysis. Furthermore, multivariate analysis demonstrated clinical stage (P = 0.037) and tumor grade (P < 0.001) as independent predictors of cancer-specific survival irrespective of other significant factors identified by univariate analysis. CONCLUSIONS: In patients with RCC involving the IVC, biological aggressiveness characterized by tumor grade rather than tumor extension would have more potential prognostic importance; therefore, more intensive multimodal therapy should be considered in patients with high grade RCC with tumor thrombus extending into the IVC. 相似文献
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Hideki Ioi Shunsuke Nakata Akihiko Nakasima Amy L Counts 《American journal of orthodontics and dentofacial orthopedics》2005,128(2):206-211
INTRODUCTION: Soft tissue analysis is a basic tool in planning orthodontic treatment. However, the components of a well-balanced Japanese facial profile have not yet been established. The purpose of this study was to assess the most-favored or most well-balanced profile from a series of facial silhouettes with varying anteroposterior lip positions by a group of Japanese orthodontists and a group of young adult Japanese dental students. METHODS: Average female and male profiles were constructed from the profiles of 30 Japanese men and women with normal occlusions. The lips in each average profile were protruded or retruded in 1-mm increments, and the 13 images were arranged with the average profile in the center. Forty two orthodontists and 42 dental students were asked to select the 3 most-favored, well-balanced profiles for each sex and rank them in order of preference. RESULTS: Both the orthodontists and the students preferred a profile with slightly retruded lips. The dental students favored a more retruded lip position for women. The least-favored profile was the most protrusive. CONCLUSIONS: These findings suggest that Japanese orthodontists and young adults prefer a retruded profile, even though Japanese profiles have historically been characterized by more convex facial features. 相似文献
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Ocular allergic reactions and inflammatory cascades in the eye involve various arachidonic acid metabolites. One such metabolite, leukotriene B4 (LTB4) was detected in bovine lenses after incubation in Tyrode's solution and analyzed by reverse phase and normal phase high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). LTB4, a product of the lipoxygenase pathway has a chemotactic potency, and may play an important role in the inflammatory cascade. Our results demonstrate the capacity of the bovine lens to synthesize LTB4. It is possible that LTB4 synthesized in lenses under some conditions plays an important role in ocular inflammatory and allergic reactions. 相似文献
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Design of a Centrifugal Blood Pump with Magnetic Suspension 总被引:1,自引:0,他引:1
Takashi Yamane Tadashige Ikeda Toyoki Orita Tatsuo Tsutsui Tomoaki Jikuya 《Artificial organs》1995,19(7):625-630
Abstract: A new concept blood pump, whose impeller is suspended by permanent magnets and a mechanical pivot without seals or ball bearings, is presented in this paper. The primary aim of the blood pump is an application to implantable artificial hearts. The prototype model is of a centrifugal type with a four-vaned semiopen impeller 50 mm in diameter. Since this mechanism has no seals or ball bearings, flow stagnation or heat generation that might cause blood cell denaturation is expected to be small. The results of performance testing for the prototype model 2 were satisfactory regarding pump head and efficiency. The radial-suspension magnets and the magnetic coupling were stable. As a result, the present mechanism has been verified to be a candidate applicable to implantable artificial hearts. 相似文献
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Minoru Sasano Mihoko Tanaka Katsuhiko Nakata Shiro Mita 《Immunopharmacology and immunotoxicology》1991,13(1):121-133
(4R)-Hexahydro-7, 7-dimethyl-6-oxo-1, 2, 5-dithiazocine-4-carboxylic acid (SA3443) is a newly synthesized cyclic disulfide compound which offers potential hepatoprotective properties.
The effect of SA3443 on the induction of natural killer (NK) and cytotoxic T lymphocyte (CTL) activities was investigated. NK activity in BALB/c mice splenic cells was investigated using YAC-1 cells as target cells. SA3443, at a dose range of 30-300 mg/kg/day, augmented NK activity significantly when administered orally once daily for 4 days before the assay. Alloantigen-specific CTL activity in splenic cells from BALB/c mice was detected 9 days after sensitization with C57BL/6 mice splenic cells. SA3443, at a dose of 100 mg/kg/day, augmented CTL activity significantly when administered orally, once daily for 4 days beginning after the sensitization and for 2 days before the assay, while a high dose of SA3443, at 300mg/kg, suppressed CTL activity.
From these results, it is thought that SA3443 may assist in the elimination of hepatitis viruses from the liver in patients with chronic active hepatitis, by the activation of NK and/or CTL activities. 相似文献
The effect of SA3443 on the induction of natural killer (NK) and cytotoxic T lymphocyte (CTL) activities was investigated. NK activity in BALB/c mice splenic cells was investigated using YAC-1 cells as target cells. SA3443, at a dose range of 30-300 mg/kg/day, augmented NK activity significantly when administered orally once daily for 4 days before the assay. Alloantigen-specific CTL activity in splenic cells from BALB/c mice was detected 9 days after sensitization with C57BL/6 mice splenic cells. SA3443, at a dose of 100 mg/kg/day, augmented CTL activity significantly when administered orally, once daily for 4 days beginning after the sensitization and for 2 days before the assay, while a high dose of SA3443, at 300mg/kg, suppressed CTL activity.
From these results, it is thought that SA3443 may assist in the elimination of hepatitis viruses from the liver in patients with chronic active hepatitis, by the activation of NK and/or CTL activities. 相似文献