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排序方式: 共有883条查询结果,搜索用时 140 毫秒
1.
Motoki Sakuraba Yukinori Sakao Akio Yamazaki Ryuta Fukai Kazu Shiomi Satoshi Sonobe Yuichi Saito Kohta Imashimizu Takeshi Matsunaga Hideaki Miyamoto 《Annals of thoracic and cardiovascular surgery》2006,12(4):267-269
We report a case of aspergilloma in an 80-year-old male patient who had no identifiable underlying disease before surgery for pneumothorax. He was hospitalized for left pneumothorax. A chest CT revealed a large bulla in the left lung apex with a nodule (diameter; 1.5 cm) at the edge of the bulla. After thoracodocesis, air leakage persisted and a large bulla and nodule were resected. Aspergillus was detected histopathologically in the nodule. Treatment with itraconazole 200 mg a day followed, and 4 months later he had no recurrent pneumothorax or Aspergillus infection. 相似文献
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Fujii T Okuda J Tsukiura T Ohtake H Suzuki M Kawashima R Itoh M Fukuda H Yamadori A 《Neuroscience research》2002,44(4):429-438
The recent advent of neuroimaging techniques provides an opportunity to examine brain regions related to a specific memory process such as episodic memory encoding. There is, however, a possibility that areas active during an assumed episodic memory encoding task, compared with a control task, involve not only areas directly relevant to episodic memory encoding processes but also areas associated with other cognitive processes for on-line information. We used positron emission tomography (PET) to differentiate these two kinds of regions. Normal volunteers were engaged in deep (semantic) or shallow (phonological) processing of new or repeated words during PET. Results showed that deep processing, compared with shallow processing, resulted in significantly better recognition performance and that this effect was associated with activation of various brain areas. Further analyses revealed that there were regions directly relevant to episodic memory encoding in the anterior part of the parahippocampal gyrus, inferior frontal gyrus, supramarginal gyrus, anterior cingulate gyrus, and medial frontal lobe in the left hemisphere. Our results demonstrated that several regions, including the medial temporal lobe, play a role in episodic memory encoding. 相似文献
4.
Taki Y Goto R Evans A Zijdenbos A Neelin P Lerch J Sato K Ono S Kinomura S Nakagawa M Sugiura M Watanabe J Kawashima R Fukuda H 《Neurobiology of aging》2004,25(4):455-463
The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter. 相似文献
5.
Shiroh Miura Kengo Kosaka Ryuta Fujioka Yusuke Uchiyama Tomofumi Shimojo Takuya Morikawa Azusa Irie Takayuki Taniwaki Hiroki Shibata 《European journal of medical genetics》2019,62(3):172-176
Spinocerebellar ataxia 27 (SCA27) is an autosomal dominant SCA caused by variants in the fibroblast growth factor 14 (FGF14) gene. We examined a Japanese SCA patient whose deceased father also suffered from SCA. The patient was a 63-year-old male. He graduated from junior high school but received no further education. The predominant complaint was slowly progressive dysarthria and gait disturbance, which appeared at age 47. He showed pathological saccadic dysmetria, saccadic intrusions into smooth pursuit eye movements, dysarthria, and limb and truncal ataxia. His gait was wide-based but he did not require a walking stick. Limb muscle strength was intact. Deep tendon reflexes were normal or slightly reduced. Pathological reflexes were absent. He demonstrated mildly impaired vibration sense in the lower limbs. There was no urinary dysfunction. Brain MRI showed cerebellar atrophy without brainstem involvement. We first confirmed the absence of repeat expansion in genes known to be responsible for SCAs 1–3, 6–8, 10, 12, 17, 36 and dentatorubral-pallidoluysian atrophy. By exome analysis, we identified a novel heterozygous variant (NM_004115, c.529A>T; Lys177X) in exon 4 of the FGF14 gene. This variant is expected to generate a truncated FGF14 protein lacking the heparin binding sites, those are likely to modify the activity of FGF14. We confirmed the absence of the variant in 502 healthy Japanese individuals by Sanger sequencing. There is no record of the variant in public databases. We conclude that the novel variation in FGF14 is causative for SCA27 in this patient. 相似文献
6.
Takanori Abe Satoshi Saito Misaki Iino Tomomi Aoshika Yasuhiro Ryuno Tomohiro Ohta Mitsunobu Igari Ryuta Hirai Yu Kumazaki Yasuhiro Ebihara Mitsuhiko Nakahira Masashi Sugasawa Shin-ei Noda Shingo Kato 《Journal of radiation research》2021,62(1):104
The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study. 相似文献
7.
[目的] 研究5,7,4’-三羟基异黄酮(genistein,GEN)对日本比目鱼(牙鲆)生殖腺性分化的作用,并在基因表达上探索其分子机制。[方法]运用日本比目鱼随饲养水温决定其性别的生物学特性,在鱼卵孵化后第30天到第100天性分化敏感期内,在27 ℃水温下饲养,会使幼鱼分化成雄性。同时,分别给予幼鱼投食GEN 10和100 μg/g饲料进行喂养染毒,直到第100天(青年期)和第300天(成年期),分别对各组比目鱼样本做病理组织切片,判断其性别和雌雄比例,并通过原位杂交和RT-PCR分析,探索它们的作用机制。[结果] GEN对27 ℃水温饲养下的比目鱼幼鱼有雌性化诱导作用,两组成年比目鱼雌性分别有不同的百分比:10 μg/g组为46.7%,100 μg/g组为96.7%,其诱导效应呈现一定剂量依赖性;比目鱼幼鱼出生后第100天时原位杂交实验显示,P450芳香化酶的mRNA在各组的雌鱼卵巢中有明显表达,但在雄鱼精巢中未见表达;而MIS(苗勒氏管抑制物质)的mRNA在各组的雌鱼卵巢中不表达,而在雄鱼精巢中能见到非常明显的表达。RT-PCR实验显示,在雌鱼卵巢中P450芳香化酶的mRNA表达被诱导,而MIS基因表达被抑制,进一步证实了原位杂交的结果。[结论] GEN对日本比目鱼的生殖腺性分化有雌性化诱导作用,其分子机制很可能是通过诱导P450芳香化酶基因表达和抑制MIS的基因表达从而发挥雌激素样干扰作用的。 相似文献
8.
Hypertension is a pervasive public health concern due to strong associations with cardiovascular diseases and stroke. Alternatively, the associations between hypertension and the risk of Alzheimer’s disease are complex and recent large sample studies reported positive associations. In this paper, we examine the associations between diastolic blood pressure (BP) and subsequent changes in brain structure and cognitive function over several years by multiple regression analyses (with adjustment for a wide range of potential confounding variables) among a large cohort from the UK Biobank. Higher baseline diastolic BP was associated with a slightly smaller relative increase (relative improvements) in reaction time and a slightly greater reduction in depression scores. Higher baseline diastolic BP was also associated with a greater total gray matter volume (GMV) retention, while aging alone was associated with GMV reduction. White matter microstructural analyses revealed that a greater diastolic BP was associated with reduced longitudinal mean and regional fractional anisotropy, greater increases in mean and regional mean diffusivity, radial diffusivity, and axial diffusivity, a greater decline in mean intracellular volume fraction, and greater increases in mean and regional isotropic volume fraction. These white matter microstructural changes were consistent with those seen in the aging process. Additional analyses revealed a greater cheese intake level at baseline, which is associated with a subsequent decline in diastolic BP and a relative subsequent increase in depressive tendency together with a relative increase in fluid intelligence and visuospatial memory performance. These results are congruent with the view that a higher BP in the aging brain has a complex role. 相似文献
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10.
Takuhiro Shoji Ryuta Saito Masayuki Kanamori Yukihiko Sonoda Mika Watanabe Teiji Tominaga 《Brain tumor pathology》2016,33(4):255-260
We present a case of sarcoma occurring at a site of resected oligodendroglioma without preceding radiotherapy or chemotherapy. Oligosarcoma occurring at sites of resected oligodendroglioma or anaplastic oligodendroglioma with sarcomatous components are rare. Although meningioma or sarcoma-like lesions are sometimes reported after glioma-targeted radiotherapy, those without preceding radiotherapy are quite rare. Moreover, cases of sarcoma without oligodendroglial components occurring at a site of resected oligodendroglioma have never been reported. In this case, fluorescent in situ hybridization analysis revealed 1p/19q co-deletion in both the first tumor and second tumors. Additionally, immunohistochemistry revealed mutated isocitrate dehydrogenase 1 in both tumors. Taken together, these findings suggest a monoclonal tumor origin. Consequently, this case may indicate a new mechanism of development of sarcomatous lesions occurring at the site of a resected glioma. 相似文献