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排序方式: 共有3087条查询结果,搜索用时 31 毫秒
1.
Hirotaka Koizuml Mikita Morita Shinya Mikaml Eiichi Shibayama Toshiyuki Uchikoshi 《Pathology international》1998,48(2):93-101
The Trk family of tyrosine protein kinase receptors plays a significant role in the development and maintenance of neural tissues. It has been recently shown that Trk receptors are also expressed by a wide range of normal non-neuronal tissues in humans in a cell type-specific manner. In the present study, the expression patterns of TrkA in 337 non-neuronal invasive carcinomas of 15 different human tissues were investigated immunohistochemically. Overall, 133 (39%), 101 (30%) and 103 (31%) tumors exhibited strong, moderate and no TrkA Immunoreactivity, respectively. Esophageal and thyroid carcinomas expressed high levels of TrkA, whereas the levels in gastric and colon cancers were low. TrkA expression was detected not only in carcinomas originating from TrkA-positive normal counterpart tissues, Including the esophagus, breast, lung and uterus, but also in those from TrkA-negative tissues/cells of the thyroid, liver and ovary. Immunostaining for nerve growth factor-β, the specific ligand for TrkA, in esophageal and breast carcinomas demonstrated its immunoreactivity in stromal fibroblasts and some TrkA-expressing tumor cells. These results suggest that paracrine/autocrine regulation via stromal/tumoral NGF-tumoral TrkA interaction may be involved In the growth of certain non-neuronal carcinomas. 相似文献
2.
Two-level posterior lumbar interbody fusion for degenerative disc disease: improved clinical outcome with restoration of lumbar lordosis 总被引:2,自引:0,他引:2
Akira Hioki MD Kei Miyamoto MD PhD Hirotaka Kodama MD PhD Hideo Hosoe MD PhD Hirofumi Nishimoto MD Hirofumi Sakaeda MD PhD Katsuji Shimizu MD DMSc 《The spine journal》2005,5(6):600-607
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis. 相似文献
3.
Hirotaka Inaba Kazuhiko Higuchi Kenji Koseni Haruo Yamauchi Junichi Naganuma 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(11):587-592
OBJECTIVE: The aortic connector system was used to minimize cerebrovascular complications when performing the proximal anastomosis of vein grafts during coronary artery bypass grafting (CABG). The goal of this study was to investigate the intermediate outcomes of patients undergoing CABG with the aortic connector system. METHODS: The aortic connector was used on nine patients undergoing CABG between November 2002 and July 2003. Intermediate outcomes of the patients were examined, and the results of coronary angiography, which were performed before patient discharge and at least 6 months after discharge, were evaluated. RESULTS: There were no operative deaths or cerebrovascular accidents. One patient died 9 months after discharge, one patient had angina, and the remaining seven patients were asymptomatic. When evaluating the results of angiography performed before patient discharge, two of the 21 distal vein graft anastomoses were occluded (patency rate, 90.5%), but there was no stenosis or occlusion at the proximal anastomoses sites that were performed using the aortic connector. When evaluating the results of the second angiography performed after patient discharge, four of the eight proximal anastomoses were patent, one was completely occluded, two had 90% stenosis and one had 75% stenosis. Further, four of the 18 distal anastomoses were occluded (patency rate, 77.8%). There was no significant difference in graft flow or device size when comparing patients with patent vein grafts and those with stenotic or occluded vein grafts. CONCLUSION: Intermediate outcomes of vein grafting using the aortic connector were suboptimal. Long-term outcome data are forthcoming. 相似文献
4.
Naomi Matsumoto Manabu Ikeda Ryuji Fukuhara Takayuki Hyodo Tomohisa Ishikawa Takaaki Mori Yasutaka Toyota Teruhisa Matsumoto Hiroyoshi Adachi Shunichiro Shinagawa Kazuhiko Hokoishi Hirotaka Tanabe Nobutsugu Hirono 《Brain and nerve》2006,58(9):785-790
OBJECTIVE: Neuropsychiatric disturbances are common and burdensome symptoms of dementia. Assessment and measurement of neuropsychiatric disturbances are indispensable to the management of patients with dementia. Neuropsychiatric Inventory (NPI) is a comprehensive assessment tool that evaluates psychiatric symptoms in dementia. We translated the NPI-Caregiver Distress Scale part of NPI (NPI-D) and NPI-Brief Questionnaire Form (NPI-Q) into Japanese and examined their validity and reliability. SUBJECTS AND METHODS: The subjects were 152 demented patients and the caregivers who lived with them. These patients consisted of 76 women and 76 men; their mean age was 73.9 +/- 7.8 (S.D.; range: 49 to 93) years. Their caregivers consisted of 46 men and 106 women; their mean age was 65.0 +/- 11.4 (S.D.; range: 35 to 90) years. The Mini-Mental State Examination (MMSE) was conducted with all patients and NPI-Q, NPI, NPI-D, and the Zarit caregiver burden interview (ZBI) were conducted with all caregivers. We examined validity of NPI-D by comparing its score with the MMSE and ZBI scores, and the validity of NPI-Q by comparing its score with the NPI and NPI-D scores. In order to evaluate test-retest reliability, NPI-D was re-adopted to 30 randomly selected caregivers by a different examiner one month later and NPI-Q was re-executed by 27 randomly selected caregivers one day later. RESULTS: Total NPI-D score was significantly correlated with ZBI (rs = 0.59, p < 0.01). Test-retest reliability of NPI-D was adequate (ri = 0.47, p < 0.01). Total NPI-Q severity score and distress score were strongly correlated with NPI (r = 0.77, p < 0.01) and NPI-D (r = 0.80, p < 0.01) scores, respectively. Test-retest reliability of the scores of NPI-Q was acceptably high (the severity score; ri = 0.81, p < 0.01, the distress score; ri = 0.80, p < 0.01). CONCLUSION: The Japanese version of NPI-D and NPI-Q demonstrated sufficient validity and reliability as well as the original version of them. These are useful tools for evaluating psychiatric symptoms in demented patients and their caregivers' distress attributable to these symptoms. 相似文献
5.
Hiromi Kataoka Takashi Joh Yusuke Inoue Naotaka Ogasawara Tadayuki Oshima Satoshi Tanida Makoto Sasaki Haruhisa Nakao Takahiro Nakazawa Hirotaka Ohara 《Digestive endoscopy》2006,18(4):294-297
A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS. 相似文献
6.
Y. Tani T. Ishihara T. Kanai T. Ohno J. Andersson A. Lilja G. Antoni K. -J. Fasth P. Bjurling G. Westerberg P. Hartvig H. Onoe Y. Watanabe B. Langström 《Journal of neural transmission (Vienna, Austria : 1996)》1995,102(3):189-208
Summary The effects of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (R-THBP) on the central cholinergic and dopaminergic systems in the Rhesus monkey brain were investigated by positron emission tomography (PET) with the muscarinic cholinergic receptor ligands (N-[11C]methyl-benztropine) and dopaminergic receptor ligands selective for D1 D2, and D3 subtypes ([11C]SCH23390, N-[11C]methyl-spiperone, and (+)[11C]UH232, respectively). None of the doses (3, 10, and 30 mg/kg i.v.) of R-THBP used significantly affected the regional cerebral blood flow (rCBF as determined by Raichle's H2
15O method), and 10 mg/kg of R-THBP had little effect on the regional cerebral metabolic rate of glucose (rCMRglc) in the Rhesus monkey brain, as assessed by the graphical [18F]fluoro-deoxyglucose method. The effect of R-THBP on the muscarinic cholinergic system was dose dependent; while 3 mg/kg of R-THBP did not significantly alter the uptake ratio of N-[11C]methyl-benztropine in several brain regions to that in the cerebellum, 10 and 30 mg/kg of R-THBP significantly reduced the uptake ratio in the thalamus, as well as in the frontal and temporal cortices. None of the doses (3, 10, and 30 mg/kg i.v.) of R-THBP tested affected [11C]SCH23390 (dopamine D1 receptor) binding. However, the k3 value for N-[11C]methyl-spiperone (dopamine D2 receptor) binding, which represents the association rate × Bmax value, was significantly decreased in the striatum. The uptake ratio of (+)[11C]UH232 (dopamine D3 receptor) in the striatum to that in the cerebellum was also decreased by administration of R-THBP (3 and 30 mg/kg i.v.). These findings suggest that R-THBP acts on dopamine D2 and D3 receptors selectively without markedly affecting dopamine D1 receptor binding. Furthermore, the changes in cholinergic and dopamine D2 and D3 receptors in vivo can not be attributed to a change in rCBF but may depend on the action of R-THBP.Abbreviations
R-THBP
6R-L-erythro-5,6,7,8-tetrahydrobiopterin
-
PET
positron emission tomography
-
rCBF
regional cerebral blood flow
-
rCMRglc
regional cerebral metabolic rate of glucose 相似文献
7.
When C57BL/10(B10) mice were immunized with a pigeon cytochrome c related peptide, 50V (AEGFSYTVANKNKGIT), two helper T cell populations with different specificity were activated. A major T cell population reacted with a 50V analog, 50V54A (AEGFSYTVANKAKGIT), more potently than with the immunogen, 50V, in a heteroclitic fashion, whereas the other minor T cell population responded only to 50V. By contrast, when bm12 mice were immunized with 50V, the minor T cell population responding only to 50V could hardly be demonstrated. The apparent deletion of the minor T cell population in bm12 mice seems to be attributable to negative selection under the influence of I-Abm12 molecules, since the minor T cell population was undetectable in both I-Ab and I-Abm12 restricted T cells from (B10 x bm12)F1 mice. Thus, three mutant points on the I-A molecule in bm12 mice appear to be involved in the seemingly negative selection of the certain T cell repertoire. The present finding demonstrates that a T cell repertoire generated under the influence of a MHC product (Ab) on one parental strain is eliminated by a different MHC product (Abm12) on the other parental strain of F1 cross. The mechanism underlying the apparent negative selection is discussed. 相似文献
8.
9.
Mitsuru Izumisawa DDS Masanori Shozushima DDS PhD Hirotaka Sato DDS PhD 《Oral Radiology》2003,19(2):47-55
Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer,
FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon
have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous
cell cancer and PET findings on FDG uptake.
Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed
by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered
dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following
parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the
primary lesion, and cell density of the tumor.
Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation,
but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage
of tumor parenchyma.
Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in
cancer tissue tends to become a false negative. 相似文献
10.
Hirotaka Itakura Shoji Kishi 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2009,247(8):1147-1150
Purpose To determine the efficacy of intravitreal injection of sulphur hexafluoride (SF6) gas for reducing persistent subfoveal fluid
after scleral buckling surgery for macula-off rhegmatogenous retinal detachments.
Methods We injected 0.3 ml of SF6 gas into the vitreous cavity of two eyes of two patients with persistent macular retinal detachment
3 and 5 months after successful scleral buckling. Optical coherence tomography was performed before and after surgery.
Results Subfoveal fluid was displaced peripheral to the fovea immediately after gas injection and the fluid was absorbed gradually
in both eyes.
Conclusions Persistent subfoveal fluid after scleral buckling may be treated with intravitreal SF6 gas injection.
The authors have no proprietary interest in any aspect of this report 相似文献