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1.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
2.
Masatoshi Chiba Takashi Shigihara Seishi Echigo Teiichi Teshima 《Journal of bone and mineral metabolism》1990,8(3):24-29
Summary In this study, we examined histologically the effect of a bone morphogenetic protein (BMP) derived from bovine tooth on the
periosteum. Supraperiosteal injection of crude BMP into femurs of Wistar rats (28 day old) resulted in periosteal cell proliferation
with subsequent bone and cartilage formation. Moreover, proliferating periosteal cells migrated into injected BMP, and formed
both cartilage and bone. These observations show that exogenous BMP stimulates mesenchymal cells of the periosteum to proliferate
and differentiate into osteoblasts, and therefore BMP may be one of factors which are involved in differentiation of osteoblasts
in the periosteum. 相似文献
3.
Hisashi Tanii Norio Taniguchi Hisayoshi Niigawa Takayoshi Hosono Yasumitsu Ikura Sakae Sakamoto Takashi Kudo Tsuyoshi Nishimura Masatoshi Takeda 《Brain research》1996,743(1-2)
The neuroleptic malignant syndrome (NMS) is a life-threatening complication of neuroleptic treatment. To elucidate the pathogenesis of NMS, an animal model has been developed. Experimental rabbits treated with haloperidol (1 mg/kg) by intramuscular injection, were studied for the diagnostic symptoms of increased muscle rigidity, elevated body temperature, and high serum creatine phosphokinase (CPK) level. Administration of haloperidol (1 mg/kg) and atropine (0.4 mg/kg), and exposure to high ambient temperature (35°C) induced a significant increase in electromyographic activity with muscle rigidity similar to that observed in patients with NMS. Such rabbits also showed elevated body temperature and serum CPK value. In addition to the similarity of the signs and symptoms, all parameters measured (muscle rigidity, body temperature, and serum CPK level) were normalized by dantrolene treatment. The effectiveness of dantrolene in the experimental animal partially confirms the validity of this animal model for NMS. This experimental animal model for NMS may be useful to elucidate the pathogenesis of NMS. 相似文献
4.
Nobuyuki Takemura Yasuhiko Sugawara Takuya Hashimoto Nobuhisa Akamatsu Yoji Kishi Sumihito Tamura Masatoshi Makuuchi 《Liver transplantation》2005,11(3):356-360
The incidence of hepatic venous stenosis is higher in partial liver transplantation. New methods for hepatic venous reconstruction in left liver transplantation, which secure wide anastomosis, were devised and are reported here. In the graft, the right side of the middle hepatic vein or the left side of the left hepatic vein was cut longitudinally and a rectangular-shaped vein patch was attached for venoplasty. In the recipient, after the left and middle hepatic veins were joined, the right side of the middle hepatic vein was cut toward the closed right hepatic vein, making a horizontal cavotomy for anastomosis. Of 92 patients who underwent conventional hepatic vein reconstruction, 3 were complicated by hepatic venous stenosis (median follow-up 43 months). By contrast, there were no hepatic vein complications in the 20 patients who underwent the new technique (7 months). The current method appears to be technically feasible for outflow reconstruction in left liver graft transplantation. 相似文献
5.
6.
Kazuta Fukumori Yoichi Yano Koutaro Kuwaki Shuji Sumie Eiji Ando Masatoshi Tanaka Michio Sata 《Nihon Shokakibyo Gakkai zasshi》2007,104(8):1225-1230
A 64-year-old man was admitted for further examinations of a liver tumor. The patient was diagnosed as chronic hepatitis C complicated with advanced hepatocelluar carcinoma (HCC) with left portal vein tumor thrombosis. As he refused surgical treatment, hepatic arterial infusion chemotherapy (HAIC) using cisplatin and 5-fluorouracil was performed initially. Administration of ursodesoxycholic acid (UDCA) was also started. Following HAIC, microwave coagulation therapy for residual tumor was added. Consequently, viable lesions of HCC disappeared completely. At present, after more than 8 years, neither signs of tumor recurrence, nor elevation of hepatic enzymes has been observed. Although the precise reason for long survival of this patient is not known, we speculate that suppression of levels of hepatic enzymes, as well as HAIC for subclinical intrahepatic metastasis, contributed to the good outcome. Therapeutic strategy for hepatic inflammation seems to be important for long-term prevention of hepatocarcinogenesis. 相似文献
7.
New sonographic techniques for the diagnosis and treatment of hepatocellular carcinoma 总被引:1,自引:0,他引:1
Masatoshi Kudo 《Hepatology research》2007,37(S2):S193-S199
Ultrasound (US) contrast agents such as Levovist and Sonazoid are now commercially available in Japan. Innovative contrast agents and ultrasound technologies have dramatically changed both diagnostic and treatment strategies for hepatocellular carcinoma (HCC). Contrast-enhanced US is extremely useful in the differential diagnosis of hepatic tumors as well as in evaluation of post-treatment response of HCC after lipiodol transarterial chemoembolization and radio frequency ablation. Harmonic US sensitively detects residual cancer cells in HCC patients after treatment, to facilitate accurate guidance for needle insertion for US monitoring; no other imaging modalities, including computed tomography (CT) or magnetic resonance imaging (MRI), have such capability. In 2005, the breakthrough technology of pure arterial phase imaging, which depicts only intranodular arterial accumulated maximum intensity projection images, was developed from advanced raw data storing and accumulation technologies. This technique can clearly identify whether blood supplyin the tumor is of arterial or portal origin, to facilitate the non-invasive characterization of nodular lesions associated with liver cirrhosis. Again, CT or MRI do not have such capabilities. This innovative technique can help differentiate premalignant lesions from overt HCC. Concurrent real-time imaging of multi-detector CT and US, known as real-time virtual sonography, has recently become available. This technique greatly facilitates the treatment guidance for HCC. These newly introduced sonographic techniques are dramatically changing the diagnostic and therapeutic strategies for HCC, which are expected to improve the prognosis of HCC patients. 相似文献
8.
Tomoko FUKUNAGA Satoshi UKAI Toshiko KOBAYASHI Tsuyoshi NISHIMURA Masatoshi TAKEDA 《Psychogeriatrics》2006,6(4):159-167
Background: Progression of the core and accessory symptoms of dementia can be slowed if drug therapies and psychosocial interventions are administered at an early stage. The aim of this study was to develop and standardize a neuropsychological test for the elderly that can detect dementia at an early stage with high sensitivity and can evaluate a wide range of severities of dementia based on assessments of various cognitive functions. Methods: A preliminary test consisting of 23 items and the Nishimura Mental State Scale for the Elderly (NM Scale), which evaluates the mental functions of elderly individuals by observing their actual behaviors in daily life, were administered to 448 elderly subjects. After applying Hayashi’s quantification theory type I to the results, we revised the preliminary test to construct a neuropsychological test for the elderly, which we named the Nishimura Dementia Test (ND Test), and standardized it. Then, we examined its validity and test–retest reliability. Results: Among the 448 subjects, there was a strong correlation between the ND Test scores and NM Scale scores. The ND Test showed a good general agreement rate for the discrimination of the severity of dementia, and good sensitivity and specificity of discrimination of dementia when compared with the actual NM Scale. Using different groups of elderly subjects, the ND Test showed validity and test–retest reliability, and the ND Test scores showed strong correlations with the Revised Hasegawa Dementia Scale scores and the Mini‐Mental State Examination scores. Conclusions: The ND Test is based on assessment of a variety of cognitive functions and can evaluate a wide range of severities of dementia with good validity and reliability. 相似文献
9.
Tetsumori Yamashima Takaomi C. Saido Masatoshi Takita Atsuo Miyazawa Jun Yamano Atsuo Miyakawa Hisashi Nishijyo Junkoh Yamashita Seiichi Kawashima Taketoshi Ono Tohru Yoshioka 《The European journal of neuroscience》1996,8(9):1932-1944
To clarify the mechanism of postischaemic delayed cornu Ammonis (CA)-1 neuronal death, we studied correlations among calpain activation and its subcellular localization, the immunoreactivity of phosphatidylinositol 4,5-bisphosphate (PIP2) and Ca2+ mobilization in the monkey hippocampus by two independent experimental approaches: in vivo transient brain ischaemia and in vitro hypoxia-hypoglycaemia of hippocampal acute slices. The CA-1 sector undergoing 20 min of ischaemia in vivo showed microscopically a small number of neuronal deaths on day 1 and almost global neuronal loss on day 5 after ischaemia. Immediately after ischaemia, CA-1 neurons ultrastructurally showed vacuolation and/or disruption of the lysosomes. Western blotting using antibodies against inactivated or activated μ-calpain demonstrated μ-calpain activation specifically in the CA-1 sector immediately after ischaemia. This finding was confirmed in the perikarya of CA-1 neurons by immunohistochemistry. CA-1 neurons on day 1 showed sustained activation of μ-calpain, and increased immunostaining for inactivated and activated forms of μ- and m-calpains and for PIP2. Activated μ-calpain and PIP2 were found to be localized at the vacuolated lysosomal membrane or endoplasmic reticulum and mitochondrial membrane respectively, by immunoelectron microscopy. Calcium imaging data using hippocampal acute slices showed that hypoxia-hypoglycaemia in vitro provoked intense Ca2+ mobilization with increased PIP2 immunostaining specifically in CA-1 neurons. These data suggest that transient brain ischaemia increases intracellular Ca2+ and PIP2 breakdown, which will activate calpain proteolytic activity. Therefore, we suggest that activated calpain at the lysosomal membrane, with the possible release of biodegrading enzyme, will cause postischaemic CA-1 neuronal death. 相似文献
10.
Hiroyuki Ishizu Masatoshi Takahashi Yukifumi Kondo Akihiko Kataoka Takashi Nakamura Kuniaki Okada Hiroyuki Masuko Yasunori Nishida Hideaki Ogawa Ryoji Yokoyama Yutaka Kimura 《Surgery today》1997,27(3):285-287
Magnetic resonance cholangiopancreatography (MRCP) was performed in 35 patients to evaluate the feasibility of its use as a postsurgical imaging technique after resection of the pancreas. The surgical procedures performed were: pancreatoduodenectomy in 22 patients, segmental pancreatectomy in 1, distal pancreatectomy in 7, and pyroluspreserving pancreatoduodenectomy in 5. The pancreatic duct was shown in its entirety in 24 of the 35 patients (68.6%) and was partially visualized in 8 patients (22.9%), but the intrahepatic and extrahepatic bile ducts were visualized completely in all patients. Furthermore, MRCP was able to demonstrate lesions in 3 of 6 patients who had shown clinical evidence of recurrence. The visualization of the pancreatic and bile duct system was satisfactory despite anatomical changes brought about by resection of the pancreas. Thus, we conclude that MRCP is an appropriate follow-up screening test for patients with suspected abnormalities of the biliary and pancreatic duct system. 相似文献