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21.
Tsunao Imamura Rie Takeshita Rikako Koyama Chikao Okuda Kazuo Takeuchi Masamichi Matsuda Masashi Hashimoto Goro Watanabe Hitoshi Yoshida Michio Imawari 《Digestive endoscopy》2006,18(4):303-307
Background: Pancreatic carcinoma is one of the most lethal cancers. Because pancreatic carcinoma is still very difficult to diagnose in its early stage, many of these patients will be considered unsuitable for surgery. If a cytological diagnosis is obtained at initial endoscopic retrograde cholangiopancreatography (ERCP), suitable treatment will be initiated without delay. Methods: To increase the number of exfoliated cells from the pancreatic duct, we devised a new technique, pancreatic duct lavage fluid (PDLF), following bronchoalveolar lavage fluid. The present paper reports the effectiveness of cytological examination using PDLF in the diagnosis of pancreatic carcinoma. We examined 18 pancreatic carcinoma cases. After the endoscopic retrograde pancreatography (ERP), PDLF was collected from a double‐lumen catheter inserted into the main pancreatic duct. Saline injected from the lumen for the injection, and PDLF was aspirated from the other lumen for the guidewire at the same time. The cytological examination was performed using PDLF. Results: Exfoliated cells were more frequently found in PDLF from all patients. In 15 cases (83%), cytological examination of PDLF revealed positive cytological results as the diagnosis of pancreatic carcinoma. Conclusion: Cytological examination using PDLF has a high sensitivity for detection of pancreatic carcinoma. The new examination, PDLF, is simple, safe and effective, so we expect PDLF to become widely popular. 相似文献
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23.
Behcet's disease (BD) is characterized by recurrent oral aphthae, skin lesions, eye lesions, and genital ulceration. To determine the pathogenesis of BD, we performed histological and immunohistochemical studies of these mucocutaneous lesions, an assay of neutrophil activity, and HLA typing. Dense dermal or subcutaneous infiltrations of polymorphonuclear cells (PMN) without leukocytoclastic vasculitis were found in 28 of 57 lesions. Immunohistochemically, deposits of C3 on the vessels were found in 12 of 31 lesions. Deposits of immunoglobulin were not found except for one of IgM. C3 deposits and PMN infiltrations were significantly related (p<0.05). PMN activity by polarization was enhanced; however, the results did not show a significant relationship with the PMN infiltrations or the C3 deposits. The incidence of HLA-B51 was significantly high in BD, but no significant relationship was found between HLA-B51 and the results of other examinations. These results suggest that the pathogenesis of BD lesions differs from that of collagen diseases and that C3 deposits on the vessels may play an important role in the development of mucocutaneous lesions where PMN have mainly infiltrated. 相似文献
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25.
Yang-Sheng Tzeng Eric Hoffman Janice Cook-Granroth Rie Maurer Niral Shah Joey Mansour Juerg Tschirren Mitchell Albert 《Magnetic resonance in medicine》2007,58(3):636-642
An anthropomorphic airway tree phantom was imaged with both hyperpolarized (HP) 3He MRI using a dynamic projection scan and computed tomography (CT). Airway diameter measurements from the HP 3He MR images obtained using a newly developed model-based algorithm were compared against their corresponding CT values quantified with a well-established method. Of the 45 airway segments that could be evaluated with CT, only 14 airway segments (31%) could be evaluated using HP 3He MRI. No airway segments smaller than approximately 4 mm in diameter and distal to the fourth generation were adequate for analysis in MRI. For the 14 airway segments measured, only two airway segments yielded a non-equivalent comparison between the two imaging modalities, while eight more had inconclusive comparison results, leaving only four airway segments (29%) that satisfied the designed equivalence criteria. Some of the potential problems in airway diameter quantification described in the formulation of the model-based algorithm were observed in this study. These results suggest that dynamic projection HP 3He MRI may have limited utility for measuring airway segment diameters, particularly those of the central airways. 相似文献
26.
H Fukatsu H Yamada H Nonomura Y Miyagawa M Waki Y Hatano S Hiraiwa T Muramatsu Y Yamada E Nishikawa 《Hinyokika kiyo. Acta urologica Japonica》1990,36(5):569-575
A total of 518 bacterial strains isolated from the urine of patients with various urological diseases in our Urological Department between November, 1987 and February, 1989 were studied for their beta-lactamase production and susceptibility to various antimicrobial agents was determined. beta-lactamase activity was determined by the acidometry disc method. There were 241 gram-positive cocci, 276 of gram-negative rods and 1 Neisseria gonorrhoeae. Thirty-four percent of the gram positive and 76.3% of gram negative rods produced beta-lactamase. S. aureus (81.3%), S. epidermidis (65.1%) in gram-positive cocci, E. cloacae (100%), S. marcescens (100%), C. freundii (100%), P. aeruginosa (97.2%), P. Rettgeri (88.9%), E. gergoviae (85.7%), K. oxytoca (84.6%), M. morganii (81.8%) and E. coli (69.0%) in gram-negative rods produced beta-lactamase at a higher rate. beta-lactamase produced by gram-positive cocci was entirely penicillinase, and that produced by gram-negative rods only penicillinase in 4.0%, only cephalosporinase in 44.2% and both in 25.4%. In S. aureus and S. epidermidis, the isolated rate of strains resistant to ampicillin (p less than 0.01) and piperacillin (p less than 0.05) in the beta-lactamase producing strains was significantly higher than that in the beta-lactamase non-producing strains. In E. coli, the isolation rate of strains resistant to ampicillin and piperacillin in the penicillinase-producing strains was significantly higher than in the penicillinase non-producing strains (p less than 0.01). But both cephalosporinase-producing strains and beta-lactamase non-producing strains showed high susceptibility to cephalothin. These results suggest that the penicillinase might present a clinical problem in the treatment of urinary tract infections by S. aureus, S. epidermidis and E. coli. 相似文献
27.
S Sato T Iiyama R Hata H Tomomasa H T Iizumi T Yazaki T Umeda H Amemiya H Muramatsu 《Nihon Jinzo Gakkai shi》1992,34(6):711-715
A 59-year-old male was admitted to our clinic for further examination of the calcified renal cyst discovered incidentally on medical workup elsewhere. CT showed a left renal cyst associated with calcification. Ultrasound-guided puncture of the renal cyst was not successful because of thickness of the cystic wall. Renal angiography showed hypervascularity of the cystic wall. Association of renal cell carcinoma could not be ruled out, therefore the exploration was performed. Histological examination revealed benign renal cyst with calcification. A 27-year-old male presented with the chief complaint of left flank pain. Following examinations by US, CT and MRI, a renal cyst associated with renal cell carcinoma was highly suspected. Subsequent exploration revealed cluster of cysts with a yellowish lesion a few mm in diameter. Frozen section revealed no malignancy, and cystic fluid was not hemorrhagic. Therefore as many cystic walls as possible were removed without nephrectomy. Histological examination of the permanent specimen revealed renal cell carcinoma. Renal cyst associated with renal cell carcinoma was regarded as rare clinical entity, but such cases are reported in increasing number in recent years. We report such cases and review the pertinent literature in this paper. 相似文献
28.
Trans-activation of glutathione transferase P gene during chemical hepatocarcinogenesis of the rat. 总被引:2,自引:0,他引:2
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S Morimura T Suzuki S Hochi A Yuki K Nomura T Kitagawa I Nagatsu M Imagawa M Muramatsu 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(5):2065-2068
Glutathione transferase P (GST-P; glutathione transferase, EC 2.5.1.18) is known to be specifically expressed at high levels in precancerous lesions and in hepatocellular carcinomas from a very early phase of chemically induced hepatocarcinogenesis in the rat. The almost invariable occurrence of this phenotype in these lesions strongly suggests a mechanism by which GST-P gene is activated together with a crucial transforming gene of liver cells. To distinguish the two alternative possibilities--either the GST-P gene is coactivated with a closely located transforming gene by a cis mechanism or it is activated in trans by a common trans-acting factor--we carried out carcinogenesis experiments using transgenic rats harboring the bacterial chloramphenicol acetyltransferase reporter gene ligated to the upstream regulatory sequence of the GST-P gene. In each of three independent lines tested, liver foci and nodules produced by chemical carcinogens (Solt-Farber procedure) were found to express high levels of chloramphenicol acetyltransferase activity, indicating clearly that the GST-P gene is activated by a trans mechanism during hepatocarcinogenesis. 相似文献
29.
S Uchida M Sumiya Y Muramatsu Y Ohmomo S Yamaguchi H Obata M Umebayashi 《Health physics》1988,55(5):779-782
Among the routes of gaseous I transfer to rice grains, direct deposition to the hull of rice plants and the subsequent transfer to brown rice and polished rice should be more critical than leaf absorption-translocation. A grain number normalized deposition velocity (Vs) is recommended as a key parameter to assess the amount of gaseous I deposited on the rough rice. This parameter is given as "iodine content per unit number of grain per unit time" divided by "iodine concentration per unit volume of the air." After the heading period the surface area of rough rice is almost constant but weight increases with time. Therefore, mass normalized deposition velocity (VD) varies with time. By introducing Vs instead of VD, the variations could be converged into narrow ranges. The contribution of gaseous I from the atmosphere to rough rice, brown rice and polished rice were estimated using Vs values obtained experimentally and gaseous I concentration in the air. 相似文献
30.
Shinichiro Hirose Yukiko Umetani Misato Amitani Rie Hosoi Sotaro Momosaki Jun Hatazawa Antony Gee Osamu Inoue 《Neuroscience letters》2007
The effect of inhibition of glial metabolism by infusion of fluorocitrate (FC, 1 nmol/μl, 2 μl) into the right striatum of the rat brain on the glucose metabolism was studied. Significant increases in [18F]fluorodeoxyglucose ([18F]FDG) uptake (45 min) in the right cerebral cortex and striatum were observed 4 h after the infusion of FC, both as determined by the tissue dissection method and autoradiography. No significant increase in the initial uptake of [18F]FDG (1 min) was seen in the striatum. Pretreatment with dizocilpine (MK-801), an N-methyl-d-aspartate (NMDA) receptor antagonist, reduced [18F]FDG uptake in not only FC infused hemisphere but also in the contralateral hemisphere (saline-infused side). The radioactivity concentrations in plasma at 1, 5 and 45 min after the [18F]FDG injection were not altered by MK-801. This effect of MK-801 on glucose metabolism observed in the rat brain infused with FC was different from previous reports which indicated an increase in glucose metabolism in some areas of normal rat brain. In addition, the enhancement of glucose metabolism in the striatum induced by FC was almost completely abolished by pretreatment with MK-801. In the cerebral cortex, the relative ratio of radioactivity concentration in the right hemisphere to that in the left hemisphere still remained 1.37 (tissue dissection method) or 1.55 (autoradiography), which indicated that MK-801 partially blocked the effect of FC of enhancing glucose metabolism in this region. These results indicate an important role of NMDA-mediated signal transmission on the increase of glucose utilization induced by inhibition of glial metabolism. 相似文献