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81.
Y Fujibayashi Y Takemura K Matsumoto K Wada Y Yonekura J Konishi A Yokoyama 《Journal of nuclear medicine》1992,33(4):545-549
In view of the high binding ability of cardiac glycosides to the myocardial Na,K-ATPase, radioiodinated digoxin derivatives were surveyed as candidates for myocardial imaging, with particular emphasis on the noninvasive monitoring of cardiac glycoside therapy. Among the radioiodinated digoxin derivatives surveyed, 125I-digoxin-iodohistamine(bis(O-carboxymethyloxime)) showed the highest accumulation in the myocardium and similar binding ability to Na,K-ATPase as digoxin itself against ouabain displacement, as indicated by in vivo and in vitro studies. Based on these results, 123I labeling of digoxin-histamine(bis(O-carboxymethyloxime)) and imaging in a dog demonstrated uptake in the myocardium. 相似文献
82.
K Iwata H Yoshimura Y Tsuji A Shirai F Uto T Tamada I Yamamoto T Tomiyama T Wada H Ohishi 《International journal of radiation oncology, biology, physics》1992,22(5):1109-1115
For intracavitary high dose-rate radiation therapy, a thermoluminescent [TL] sheet for in vivo measurement of spatial dose distribution around source has been recently developed. The TL sheet was found to have a linear response with a very wide dynamic range from at least 0.002 cGy to 5000 cGy for 60Co gamma-rays. This TL sheet (40 cm x 50 cm x 200 microns), which is composed of Teflon mixed with BaSO4:Eu doped powder, is very flexible and can be cut to the desired size. In addition, this sheet is easy to handle because of its insensitivity to room light. The spatial dose distribution is displayed in a color mode by using a newly developed TL sheet readout system. For a clinical application, the TL sheet was wrapped on an applicator for intracavitary radiation therapy of a rectal cancer and was inserted into the rectum. The location of the TL sheet could be confirmed with diagnostic X ray film. After irradiation with high dose-rate 60Co source, the in vivo relative dose distribution on the surface of the rectum was determined. This TL sheet provided a convenient means of measuring the relative dose distributions around 60Co sources of various patterns in intracavitary radiation therapy. 相似文献
83.
Ruri Aoki Tetsuya Arinobu Takeshi Kumazawa Hideki Hattori Hiroshi Noguchi 《Forensic Toxicology》2007,25(1):8-15
An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography
(HPLC)/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-μl
portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis
HLB cartridge was used as the precolumn for extraction; large molecules such as proteins in serum were discarded by use of
distilled water containing 0.1% formic acid as a mobile phase. After switching a valve, the analytes trapped in the precolumn
were eluted in the backflush mode and separated by a Chromolith Performance RP-18e column, which is composed of C18-bonded monolithic silica. The column effluents were then introduced into the SSI-MS. The present method provided successful
separation and determination of six phenothiazines including an internal standard. Satisfactory linearities, reproducibility,
and sensitivity were obtained at concentration levels that matched the toxic levels of phenothiazines. All drug peaks appeared
within 18 min, and the system could be reequilibrated in only about 8 min for the next run. Because of the simplicity and
rapidness of the method, it is likely to be useful in the fields of emergency medicine and forensic toxicology. 相似文献
84.
Motoaki Nakamura Dean F Salisbury Yoshio Hirayasu Sylvain Bouix Kilian M Pohl Takeshi Yoshida Min-Seong Koo Martha E Shenton Robert W McCarley 《Neuropsychopharmacology》2007,62(7):773-783
BACKGROUND: Overall neocortical gray matter (NCGM) volume has not been studied in first-episode schizophrenia (FESZ) at first hospitalization or longitudinally to evaluate progression, nor has it been compared with first-episode affective psychosis (FEAFF). METHODS: Expectation-maximization/atlas-based magnetic resonance imaging (MRI) tissue segmentation into gray matter, white matter (WM), or cerebrospinal fluid (CSF) at first hospitalization of 29 FESZ and 34 FEAFF, plus 36 matched healthy control subjects (HC), and, longitudinally approximately 1.5 years later, of 17 FESZ, 21 FEAFF, and 26 HC was done. Manual editing separated NCGM and its lobar parcellation, cerebral WM (CWM), lateral ventricles (LV), and sulcal CSF (SCSF). RESULTS: At first hospitalization, FESZ and FEAFF showed smaller NCGM volumes and larger SCSF and LV than HC. Longitudinally, FESZ showed NCGM volume reduction (-1.7%), localized to frontal (-2.4%) and temporal (-2.6%) regions, and enlargement of SCSF (7.2%) and LV (10.4%). Poorer outcome was associated with these LV and NCGM changes. FEAFF showed longitudinal NCGM volume increases (3.6%) associated with lithium or valproate administration but without clinical correlations and regional localization. CONCLUSIONS: Longitudinal NCGM volume reduction and CSF component enlargement in FESZ are compatible with post-onset progression. Longitudinal NCGM volume increase in FEAFF may reflect neurotrophic effects of mood stabilizers. 相似文献
85.
Keiko Imamura Kenji Wada Kenichi Yasui Kazuhiro Nakaso Yasuhiro Watanabe Hisanori Kowa Kenji Nakashima 《Clinical neurology》2004,44(7):446-449
A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors. 相似文献
86.
K Wada D Nishi T Kitamura K Ono T Takahara T Shirotani A Shimizu 《Undersea & hyperbaric medicine》2006,33(6):399-405
Moderate hypothermia may have a beneficial effect on the neurological outcome. However, ischemic deterioration such as brain swelling during rewarming has been reported as a notable complication after successful therapeutic cerebral hypothermia. In this study, we investigated the effects of hyperbaric oxygenation during rewarming. Forebrain ischemia was produced in 24 gerbils and sham ischemia in 8 animals. Then ischemia-treated animals were divided into 3 groups, whole-body moderate hypothermia (31 degrees C for 60 min) and hyperbaric oxygenation (HBO2) (2- atmosphere absolute for 60 min using 100% oxygen) during rewarming group (n = 8), moderate hypothermia without HBO2 group (n = 8), and sham treatment without hypothermia and without HBO2 group (n = 8). Both the hypothermia group (77.9 +/- 48.1 neurons per mm, mean +/- SD) and hypothermia + HBO2 group (127.6 +/- 29.7 neurons per mm,) showed significant preservation of CA1 pyramidal neurons in the hippocampus compared to that in the sham treatment group (6.4 +/- 2.7) (p < 0.01). Furthermore, the hypothermia + HBO2 group showed significantly greater preservation of CA1 pyramidal neurons than the hypothermia group (p < 0.05). These results suggest that HBO2 during rewarming preserves the protective effect of hypothermia against ischemic neuronal damage. 相似文献
87.
Masaaki Kohta Hiroaki Minami Kazuhiro Tanaka Keiichi Kuwamura Takeshi Kondoh Eiji Kohmura 《Journal of clinical neuroscience》2007,14(2):167-170
A 52-year-old man fell from standing and a computed tomography (CT) scan revealed traumatic intracerebral haematoma and subarachnoid haemorrhage in the temporal cortex. He was treated without surgery and discharged. On day 30 after the accident, he had no neurological deficit. On day 37 he complained of headache and urinary incontinence, and on day 39 he was hospitalized due to progressive neurological deterioration (reduced conciousness, dilated pupils, and left hemiplegia). A CT scan revealed a diffuse low-density in the right cerebral hemisphere with marked midline shift. Emergency decompressive craniectomy and right temporal lobectomy were performed. Angiography after surgery revealed moderate vasospasm in the right middle and anterior cerebral arteries. The patient remained severely disabled. Delayed onset neurological deterioration can be caused by brain oedema and vasospasm after traumatic brain injury, despite an intervening period of improvement. 相似文献
88.
Endogenous bone-marrow-derived stem cells contribute only a small proportion of regenerated myocardium in the acute infarction model. 总被引:6,自引:0,他引:6
Shinya Fukuhara Shinji Tomita Takeshi Nakatani Chikao Yutani Soichiro Kitamura 《The Journal of heart and lung transplantation》2005,24(1):67-72
BACKGROUND: Our recent study showed that granulocyte-colony stimulating factor (G-CSF) promoted bone-marrow cells (BMC) to migrate into the infarcted heart and that they differentiated into cardiomyocytes. However, we still do not know to what degree bone-marrow-derived cardiomyocytes contribute to myocardial regeneration after injury. In this study, we verified the proportional contribution of cells from bone marrow (BM) and from non-bone marrow (n-BM) in regenerating neomyocardium after myocardial infarction. METHODS: Eight C57BL/6 mice were irradiated (900 cGy), and green fluorescent protein (GFP) mouse-derived BMCs (GFP-BMC, 1 x 10(6) cells) were injected. Four weeks later, the left descending coronary artery was ligated. Recombinant human G-CSF (200 microg/kg/day, 8 days) was injected. At 4 weeks after ligation, hearts were fixed for histology. We calculated the proportions of cardiomyocytes derived from BM and n-BM after taking the chimeric rate into consideration. RESULTS: The chimeric rate was 54.6% +/- 5.9%. At the infarcted border area, the total cell number was 1000.3 +/- 56.5/mm(2), and mobilized BM-derived GFP-BMC was 103.3 +/- 13.1/mm(2). After compensation with the chimeric rate, we found BM-derived troponin I-positive cells at 23.9 +/- 4.1/mm(2), nestin-positive cells at 12.9 +/- 2.6/mm(2), and Ki67-positive cells at 18.3 +/- 2.6/mm(2), respectively. We found significant differences in the contribution of troponin I-(6.7% +/- 1.7% vs 93.3% +/- 1.7%), nestin- (2.4 +/- 0.5 vs 97.6 +/- 0.5), and Ki67-positive (3.9 +/- 1.0 vs 96.1 +/- 1.0) cells derived from BM and n-BM. CONCLUSIONS: Bone marrow was one of the origins of regenerated cardiomyocytes; however, the contribution of cells from BM was very small compared with those of n-BM origin in the infarction model. 相似文献
89.
Naohito Mikuma Hideki Adachi Keiji Takatsuka Akifumi Yokoo Hideki Wada Atsushi Takahashi 《International journal of urology》1996,3(3):243-244
A rare adult case of a left ectopic ureterocele associated with a duplex horseshoe kidney is reported. To the best of our knowledge, only one pediatric case of horseshoe kidney with an ectopic ureterocele has been reported. The present case was successfully treated by ureteropyelostomy, upper ureterectomy and unroofing of the ureterocele. The patient is currently followed with excretory urograms and renograms. 相似文献
90.
W Sakamoto T Kishimoto M Nishisaka H Iimori S Wada R Yasumoto K Yamamoto M Maekawa S Sukano K Umeyama 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(2):230-235
We retrospectively reviewed 32 patients who underwent parathyroidectomy at our hospital for the last fourteen years. 1) Clinical appearance of primary hyperparathyroidism was in younger age in women. 2) In previous history or at the time of PTX, 9 patients had malignant tumors including 6 thyroid cancers, 36% of the patients with out bone related symptoms had a remarkable decrease in bone mineral content. 3) After PTX, none of patients had recurrent urolithiasis and bone mineral content of all patients was significantly increased in a short time. In addition, upper GI complaints were improved, or hypertension was partially normalized. However, renal insufficiency remained unchanged. 4) In preoperative localization study, Ultrasound sonography (US) demonstrated the best accuracy rate of 88% when only one gland was involved. US was able to detect multiple gland involvement only in 20% of 5 cases. 5) Hypercalciuria was recognized as one of the risk factors of stone formation in patients with primary hyperparathyroidism. 相似文献