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21.
22.
K Tanaka Y Fukuuchi S Gomi S Takashima B Mihara T Shirai S Nogawa H Nozaki E Nagata 《Experimental neurology》1992,117(3):254-259
The alterations of second-messenger ligand binding and cerebral blood flow (CBF) were evaluated in the gerbil brain after 2-h unilateral common carotid artery occlusion. [3H]Forskolin (FK) and [3H]phorbol-12,13-dibutyrate (PDBu) were used as specific ligands for adenylate cyclase (AC) and protein kinase C (PKC) activity estimation, respectively. CBF was determined at the end of the experiment by the [14C]iodoantipyrine method. A quantitative autoradiographic method permitted simultaneous measurement of the three parameters in the same brain. The levels in the caudate-putamen, globus pallidus, and hippocampus were analyzed. The animals were divided into three groups: Group 1 with severe ischemia (CBF in the lateral nuclei of the thalamus (CBFt) less than 50 ml/100 g/min), Group 2 with mild ischemia (CBFt greater than or equal to 50 ml/100 g/min), and the Sham Group. The PDBu binding revealed a statistically significant increase in the caudate-putamen, lateral nuclei of the thalamus and hippocampus (CA1 and CA3 regions and dentate gyrus) on the ischemic side in Group 1 as compared to that in Group 2 and the Sham Group. In contrast, the FK binding did not show any significant changes in any of the regions. These data and our previous findings for 6-h ischemia suggest that (1) PKC translocation to the cell membrane may occur at the early ischemic phase in particular regions including the caudate-putamen, lateral nuclei of the thalamus and hippocampus, with the translocated PKC gradually diminishing during the subsequent ischemic period; and (2) the suppression of the AC system observed in 6-h ischemia may not appear in the early ischemic phase. 相似文献
23.
S Miyamoto H Kikuchi J Karasawa I Nagata N Yamazoe Y Akiyama 《Journal of neurosurgery》1988,68(4):537-543
Eleven cases of moyamoya disease refractory to indirect non-anastomotic revascularization, including encephalomyosynangiosis in two, encephaloduroarteriosynangiosis in seven, and encephalomyoarteriosynangiosis in two, are described. The patients suffered from recurrent cerebral ischemic symptoms, and further operative intervention, including superficial temporal artery-middle cerebral artery anastomosis and intracranial omental transplantation, was performed. The choice of operative maneuver depended on the availability of scalp arteries and on the nature of the ischemic symptoms. Although indirect non-anastomotic revascularization procedures have the advantage of technical ease and most patients respond to these procedures alone, there are some patients like the 11 presented here who are not cured by such procedures. In such cases, direct anastomotic revascularization is necessary for the prevention of stroke. 相似文献
24.
Kazumasa Miyake Atsushi Tatsuguchi Mikiko Tachibana Masanobu Kusunoki Yoko Shinji Kei Shinoki Tetsuro Hiratsuka Kazuhiro Nagata Hitoshi Nishigaki Seiji Futagami Ken Wada Taku Tsukui Toshiro Yoshiyuki Akira Tokunaga Takashi Tajiri Choitsu Sakamoto 《Digestive endoscopy》2004,16(2):172-175
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia. 相似文献
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27.
Cerebral aspergillosis after burr-hole surgery for chronic subdural hematoma: case report 总被引:1,自引:0,他引:1
We report a case of aspergillosis in the subdural space and frontal lobe in an 83-year-old man. The clinical course simulated that of a brain tumor. The source for the infection was considered to be the previous burr-hole surgery for chronic subdural hematoma, which was performed 2.5 years before the onset of symptoms. The patient was treated by removal of the abscess and granuloma. The clinical features and treatment of aspergillosis after neurosurgical procedures are discussed. 相似文献
28.
Clinical evaluation of a potassium nitrate dentifrice for the treatment of dentinal hypersensitivity
Toshihiko Nagata Hiroshi Ishida Hiroyuki Shinohara Seiji Nishikawa Shinji Kasahara Yoichi Wakano Shusaku Daigen Emanuel S. Troullos 《Journal of clinical periodontology》1994,21(3):217-221
Abstract The effectiveness of a 5% potassium nitrate dentifrice as a daily home treatment for dentinal hypersensitivity was evaluated in a double-blind study in 36 Japanese subjects who complained of cold and/or tactile hypersensitivity. The subjects were divided into 2 groups, with 18 being given a 5% potassium nitrate dentifrice (treated group) and the other 18 a vehicle paste (control group). Both groups were instructed to brush their teeth 2 × a day. The hypersensitivity levels of the affected teeth were assessed by 2 stimuli, one tactile and the other cold air, and by the perception of pain. The results of all 3 assessment methods indicated that the potassium nitrate dentifrice significantly decreased the level of hypersensitivity at weeks 4, 8, and 12. In the treated group, a rapid decrease of positive scores for both the cold air stimulus and the subjective symptoms appeared from week 2. Although a significant decrease of the assessment score was also observed in the control group, the reduction rate of the score was much greater in the treated group by ail 3 assessment methods at weeks 4, 8, and 12. Complete relief of subjective symptoms throughout the 12 weeks’examination was noted in 67% of the subjects in the treated group, but in only 6% in the control group. These results suggest the usefulness of a 5% potassium nitrate dentifrice in Japanese patients with dentinal hypersensitivity. 相似文献
29.
Radiographic studies of three cases of hypoplasia of the humeral trochlea were done. Several other anomalies were also detected, including a hypoplastic capitellum in case 2, a hyperplastic radial head in cases 2 and 3, and bulging of the loose joint capsule in case 3. Operations in cases 1 and 3, disclosed that ganglions and fibrous septa compressed the ulnar nerve. The cause of ulnar nerve palsy in patients with hypoplasia of the humeral trochlea is thought to be associated with the high incidence of ganglions in hypoplastic elbow joints. The ganglion may play a role. 相似文献
30.
M Ishikawa H Kikuchi I Nagata S Yamagata W Taki Y Yonekura S Nishizawa Y Iwasaki T Mukai 《Neurologia medico-chirurgica》1990,30(6):377-381
To investigate the value of direct measurement of the rate constants by performing 18F-labeled fluorodeoxyglucose (FDG) studies of glucose consumption in human gliomas in vivo, a kinetic method with 3- and 4-parameter rate constant models for FDG uptake was used to analyze data from dynamic scans obtained by positron emission tomography after injection of FDG into 14 patients with glioma. The results were compared with those obtained by the autoradiographic method using 3- and 4-parameter rate constant models. There were no significant differences in the glucose consumption calculated by the four different methods both in the gliomas and in the contralateral intact cortex. It was found that the rate constant k4* could be neglected in calculation of glucose consumption in gliomas as well as in the contralateral intact cortex. The rate constant k3*, an index of hexokinase function, was higher in malignant gliomas than in benign gliomas and was close to that in the contralateral cortex. This study indicates that the 3-parameter autoradiographic method, which is the most common one used in clinical practice, is reliable for the calculation of glucose consumption in human gliomas. Furthermore, direct measurement of the regional rate constants for FDG by the kinetic method was found to be useful for evaluation of the biochemical and physiological characteristics of human gliomas in vivo. 相似文献