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排序方式: 共有683条查询结果,搜索用时 31 毫秒
41.
Pulmonary dirofilariasis: computed tomography findings and correlation with pathologic features 总被引:2,自引:0,他引:2
Oshiro Y Murayama S Sunagawa U Nakamoto A Owan I Kuba M Uehara T Miyahira T Kawabata T Kuniyoshi M Ishikawa K Kinjyo T Fujimoto K Yamada K 《Journal of computer assisted tomography》2004,28(6):796-800
OBJECTIVE: The purpose of this study was to describe the computed tomography (CT) and pathologic features of 5 nodules of pulmonary dirofilariasis in 4 patients. METHODS: Four patients with 5 nodules of pathologically confirmed pulmonary dirofilariasis who under went CT were enrolled, and the imaging interpretations were retrospectively compared with the histopathologic characteristics. RESULTS: Three of the 4 patients had a solitary nodule, and the remaining patient had 2 nodules. All the nodules were distributed in the right lower lobe and were attached to the pleura. They were all round or oval in shape and ranged in size from 11 to 22 mm in largest diameter (mean=17 mm). On thinner section CT, the nodules had a well-defined smooth margin with or without a shallow notch; they were connected to the arterial branch and, occasionally, to the venous branch. On contrast-enhanced CT, all the nodules contained a homogeneous low-attenuation area, which corresponded to areas of coagulative necrosis on histopathologic examination. CONCLUSION: Although the CT findings of a pulmonary dirofilariasis nodule are nonspecific, awareness of the findings on contrast-enhanced CT and the pathologic appearance of this rare benign condition may facilitate its differentiation from a malignant nodule. 相似文献
42.
As the neural substrates of second language (L2) acquisition are largely unknown, they may or may not be similar to those of first language (L1) representation. We used functional imaging to examine whether training in the conjugation of English verbs from present to past tense alters brain activations in 13-year-old twins. A novel experimental design contrasted past tense verb identification and verb matching, which were tested in either English (L2) or Japanese (L1). After 2 month classroom training in the past tense using bingo games, the two individuals in each pair exhibited significantly correlated performances. When pre- and post-scanning sessions were compared with each other for L2, the left dorsal inferior frontal gyrus (IFG) exhibited significantly correlated activation increases within each pair of twins and the increases were positively correlated with individual performance improvements. Moreover, the cortical plasticity for L2 acquisition was guided toward the L1 specialization of the left dorsal IFG, in spite of notable differences between L1 and L2 in the students' linguistic knowledge and in their performance in making past tense forms. These findings suggest a cortical mechanism underlying L2 acquisition, which critically depends on shared genetic and environmental factors for each twin in a surprisingly predictive manner. 相似文献
43.
Kuniyoshi Y Koja K Miyagi K Shimoji M Uezu T Arakaki K Yamashiro S Mabuni K Senaha S Nakasone Y 《The Annals of thoracic surgery》2003,76(5):1477-1484
BACKGROUND: We present data showing the impact of sequential multisegmental aortic clamping accompanied by reimplantation of as many segmental arteries as possible on the prevention of postoperative paraplegia or paraparesis during thoracoabdominal aortic graft replacement. METHODS: Since 1987 we have performed graft replacements in 51 individuals undergoing thoracoabdominal aortic surgery using the technique of normothermic partial bypass with sequential multisegmental aortic clamping. The procedure was performed emergently in 10 patients and electively in 41 patients. The patients ranged in age from 22 to 82 years (mean, 57.6 +/- 13.8 years). Indications for surgery included dissecting thoracoabdominal aortic aneurysm (n = 19) and nondissecting thoracoabdominal aortic aneurysm (n = 32). The extent of aneurysm was Crawford type I in 19 patients, type II in 7 patients, type III in 12 patients, and type IV in 13 patients. Along the entire extent of aneurysm to be replaced, we reimplanted as many of the patent segmental arteries as feasible. RESULTS: Five patients died during hospitalization, for an in-hospital mortality rate of 9.8%. The number of aortic clampings per patient ranged from one to five (median, three). A total of 124 segmental arteries were reimplanted in 44 (86.3%) of 51 patients. Of the 124 arteries, 90 (72.6%) were distributed between T9 and L2. Postoperative paraplegia or paraparesis did not develop in any of the patients. CONCLUSIONS: Our results demonstrate that extensive reimplantation of segmental arteries using sequential multisegmental aortic clamping, accompanied by adequate intraoperative distal aortic perfusion, is effective in preventing spinal cord ischemia. 相似文献
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Kuniyoshi K Uno N Irifune M Shimomura Y 《Documenta ophthalmologica. Advances in ophthalmology》2003,106(3):311-318
To record electroretinograms (ERG) produced by short-wavelength-sensitive cone mechanisms (SWS-cone ERG), the authors used three kinds (blue, green, and red) of light-emitting diode (LED) which were built into a contact lens electrode assembly. The LEDs were used as both stimulus and background light sources. ERG was recorded using blue LED after 10 min of yellow light adaptation produced by green and red LEDs. Duration of photo-stimulation was either 2 or 100 ms. ERG recorded in normal human subjects showed two positive waves with 2 ms photo-stimulation. Amplitude of the former positive wave (b1-wave) was attenuated when the luminance of yellow background increased, and the latter positive wave (b2-wave) was attenuated when the color of photo-stimulation was green or red. These findings suggest that middle-wavelength-sensitive and long-wavelength-sensitive cone mechanisms generated the former positive wave (b1-wave) and SWS-cone mechanisms generated the latter positive wave (b2-wave). Ratio of b2-wave-amplitude to b1-wave-amplitude with 2 ms photo-stimulation measured on 39 normal subjects ranged from 0.5 to 2.0. It was concluded that this three-colored LED built-in electrode was useful for recording SWS-cone ERG. 相似文献
47.
Arai K Iwasaki Y Kimura Y Takahashi K Yamaguchi T Honma S Takahashi T 《Gan to kagaku ryoho. Cancer & chemotherapy》2003,30(9):1297-1301
The efficacy and safety of the oral fluoropyrimidine TS-1, which contains a dihydropyrimidine dehydrogenase (DPD) inhibitor, were examined in fifty-five patients with gastric cancer. The patients were divided into 28 with measurable cancer lesions (TUM group) and 27 without them (ADJ group). The total number of courses was 164 (mean: 5.9 courses) in the TUM group and 146 (mean; 5.4 courses) in the ADJ group. The response rate in the TUM group, excluding three patients who could not be evaluated because of incomplete administration, was 40% (CR: 4, PR: 6, NC: 6, PD: 9). Among responders, the mean number of courses to response was 2.2 and the median survival time (MST) was 21.7 months. In terms of safety, adverse reactions appeared in forty-five patients (82%) and the incidence was higher in the ADJ group. Major toxicities were leukopenia (38%), anorexia (27%), increased total bilirubin concentration (25%) and diarrhea (24%). Adverse reaction of grade 3 was found in only three patients (5.5%) and there were no drug-related deaths. In conclusion, TS-1 is safe and effective if attention is given to biweekly examinations for the development of adverse reactions. 相似文献
48.
Clinical outcome and survival after palliative surgery for spinal metastases: palliative surgery in spinal metastases 总被引:3,自引:0,他引:3
Hirabayashi H Ebara S Kinoshita T Yuzawa Y Nakamura I Takahashi J Kamimura M Ohtsuka K Takaoka K 《Cancer》2003,97(2):476-484
BACKGROUND: The authors sought to identify treatment-related factors that influenced survival after surgical treatment for metastatic spinal tumors and to evaluate the relationship between survival and postoperative ambulation time as a factor related to quality of life. METHODS: The medical records of 81 patients with metastatic spinal tumors who underwent palliative surgery at the study institution were assessed. Univariate analysis for factors influencing survival used the Kaplan-Meier log rank statistic and multivariate analysis used the Cox proportional hazards model. The Spearman correlation test was used to analyze the relationship between postoperative ambulation and survival time. RESULTS: The patients had a median age of 59.9 years and a median survival of 10.6 months after surgery. For patients, postoperative ambulatory median survival was 16.5 months and median ambulation time was 13.8 months. By univariate analysis, anatomic site of the primary tumor, postoperative ambulation, and combined adjuvant therapy (chemotherapy plus radiotherapy) were associated with prolonged survival (P < 0.05). Multivariate analysis identified primary site and postoperative ambulatory function as independent predictors of prolonged survival (P < 0.0001). Significant correlations were found between ambulation time and survival time of patients who were able to walk after surgery (P < 0.0001), even in patients with liver (P < 0.05) or lung carcinoma (P < 0.05). CONCLUSIONS: The anatomic site of primary carcinoma and postoperative ambulation were associated with longer survival after palliative surgery for metastatic spinal tumor. When ambulation is attained after surgery, it can be preserved until late in remaining life even when the primary tumor is unfavorable. Palliative surgery for spinal metastasis can improve the quality and quantity of life. 相似文献
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An event-related fMRI study of explicit syntactic processing of normal/anomalous sentences in contrast to implicit syntactic processing 总被引:1,自引:0,他引:1
Using event-related functional magnetic resonance imaging (fMRI), we examined activation of cortical language areas for explicit syntactic processing. In a syntactic decision (Syn) task, the participants judged whether the presented sentence was syntactically correct, where syntactic knowledge about the distinction between transitive and intransitive verbs was required. In a semantic decision (Sem) task, lexico-semantic knowledge about selectional restrictions was indispensable. In a phonological decision (Pho) task, phonological knowledge about accent patterns was required. The Sem and Pho tasks involved implicit syntactic processing, as well as explicit semantic and phonological processing, respectively. We also tested a voice-pitch comparison (Voi) task in which no explicit linguistic knowledge was required. In the direct comparison of Syn - (Sem + Pho + Voi), we found localized activation in the left inferior frontal gyrus (F3op/F3t), indicating that activation of the left F3op/F3t is more prominently enhanced in explicit syntactic processing than in implicit syntactic processing. Moreover, we determined that its activation is selective to syntactic judgments regarding both normal and anomalous sentences. These results suggest that explicit information processing in the syntactic domain critically involves the left F3op/F3t, which is functionally separable from other regions. 相似文献