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21.
N. Ozaki D. Nakahara Y. Kasahara T. Nagatsu 《Journal of neural transmission (Vienna, Austria : 1996)》1991,86(3):175-179
Summary The suprachiasmatic nucleus (SCN) has been identified as a major circadian pacemaker. Methamphetamine has been shown to modify the behavior of circadian rhythms. We detected extracellular serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the SCN in freely moving rats, using a microdialysis method, to investigate biochemical effects of methamphetamine in the SCN. Methamphetamine infusion into the SCN dose-dependently increased extracellular 5-HT and decreased extracellular 5-HIAA. 相似文献
22.
Tadashi Kano MD Toshiro Koga Kuniyasu Souda Yoshishige Abe Tomohiro Yonemura Naokata Oka Kiyoshi Inokuchi 《Surgery today》1987,17(4):269-275
The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated
from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25
of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression.
Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis
(68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found
prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time
of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients
with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after
the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those
with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive
CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection
of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results. 相似文献
23.
Kengo Yoshimitsu Hiroshi Honda Kuniyuki Kaneko Toshiro Kuroiwa Hiroyuki Irie Takashi Ueki Kazuo Chijiiwa Kenji Takenaka Kouji Masuda 《Journal of magnetic resonance imaging : JMRI》1997,7(4):696-701
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions. 相似文献
24.
25.
Hideaki Anai Yoshihiko Maehara Tatsuo Oshiro Hideo Baba Hiroyuki Orita Toshiro Okuyama Keizo Sugimachi 《Journal of surgical oncology》1993,53(3):204-207
In 268 of the 1,115 patients (24.0%) with gastric cancer who underwent a curative resection in our clinics, the tumor was located in the middle third of the stomach. The clinicopathological features and prognosis of these patients were divided into two groups, according to site of the tumor: anterior wall (n = 58) vs. other sites (n = 210). Clinicopathological factors did not differ between the two groups. The survival time for patients with a tumor in the anterior group was shorter than that for patients with a tumor in other areas (P < 0.05). The five-year survival rate was 79.3% for patients with an anterior tumor and 91.9% for those with a tumor at a different site. A multivariate analysis indicated lymph node metastasis, serosal invasion, and anterior wall location to be independent prognostic factors indicative of a poor prognosis when the tumor was located in the middle third of the stomach. For such patients, close follow-up is needed to detect possible recurrences. © 1993 Wiley-Liss, Inc. 相似文献
26.
Haruhisa Matsuguma Rie Nakahara Masaki Anraku Tetsuro Kondo Yukio Tsuura Yukari Kamiyama Kiyoshi Mori Kohei Yokoi 《European journal of cardio-thoracic surgery》2004,25(6):1102-1106
Objective: The standard operation for patients with stage IA lung adenocarcinoma is considered to be a lobectomy. Recently, some researchers have reported that patients with tumors showing greater proportions of ground-glass opacity (GGO) at computed tomography (CT) could be candidates for limited resection, because of its less aggressive nature. However, the lack of a precise definition or standard measuring method of GGO prevents its general use as an index for planning limited resection. Therefore, we attempted to define GGO based on CT number and measured it more objectively. Methods: Between 1998 and 2001, 90 patients with clinical stage IA adenocarcinoma, who underwent standard or intentional limited resection and whose images of chest high-resolution CT were preserved in Digital Imaging and Communications in Medicine (DICOM) format, constituted the study population. The tumor shadow seen on the solid window (WL, −160 HU; WW, 2 HU) was regarded as the central solid area of the tumor seen on the lung window, and GGO was defined as the whole tumor area with the exception of the central solid area. Each area was measured using Scion Image (Scion Corp., Frederick, MD). We analyzed the relationship between the proportion of GGO and both of pathologic findings and recurrence. Results: Among the 90 tumors, 31 (34.4%) were calculated to have a GGO area greater than or equal to 50%. Of these, 27 (87%) tumors were bronchioloalveolar carcinoma. Lymphatic and vascular invasions, or nodal involvement were found only in patients with a smaller proportion of GGO (<50%) (P<0.05). During the follow-up period (median 36 months), recurrences occurred in eight patients who were diagnosed as having tumors showing smaller proportion of GGO (<50%). Conclusions: Tumors with a greater proportion of GGO measured by our method are thought to have a less invasive nature. Our objective measuring method of GGO could be useful for future multicenter trials to elucidate the value of limited resection for clinical stage IA adenocarcinoma based on the proportion of GGO. 相似文献
27.
Dr. Shosaku Nakahara M.D. Hideaki Itoh M.D. Ryuichi Mibu M.D. Shinichi Ikeda M.D. Yoshihiro Oohata M.D. Kamesaburo Kitano M.D. Yoshihiko Nakamura M.D. 《Diseases of the colon and rectum》1988,31(10):762-766
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line,
using an EEA™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following
surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients
could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure
and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct
tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily
by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation
is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is
a functionally acceptable option for low rectal cancer. 相似文献
28.
29.
Clinical usefulness of the WHO histological classification of thymoma. 总被引:12,自引:0,他引:12
Satoshi Sonobe Hideaki Miyamoto Hiroshi Izumi Bunsei Nobukawa Toshiro Futagawa Akio Yamazaki Tumin Oh Toshimasa Uekusa Hiroshi Abe Koichi Suda 《Annals of thoracic and cardiovascular surgery》2005,11(6):367-373
PURPOSE: Rosai et al. published the World Health Organization (WHO) classification of thymic epithelial tumors in 1999, and its clinical usefulness seems to be established. It is our purpose to find the clinically relevant diagnostic points in the WHO Histological Classification of Thymoma. METHODS: Thymomas surgically removed from 100 consecutive patients at Juntendo University Hospital between October 1983 and February 2002 were classified according to the WHO histological classification. We assessed overall survival and recurrence-free rate calculated for each tumor type in the WHO classification compared with those of tumors classified by the Masaoka system. RESULTS: The thymic epithelial tumors in this series comprised 10 type A, 15 type AB, 18 type B1, 21 type B2, 33 type B3, and 3 type C tumors according to the WHO classification. Based on the Masaoka system, the disease was stage I in 53 patients, stage II in 30, stage III in 15, and stage IV in 2. The 15-year recurrence-free rate was 100% for type A, AB and B1, while the rates for types B2 and B3 were 66.7% and 54.5%, respectively. The 10-year recurrence-free rate was 66.7% for type C. The 15-year recurrence-free rate of the 64 patients with type A, AB, B1, and B2 thymomas was significantly higher from that of the 33 patients with type B3 thymoma (p=0.0026). CONCLUSION: When using the WHO classification, it is critical to distinguish type B3 thymoma from other tumor types. 相似文献
30.