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991.
We describe here a patient with a recurrent hemangiopericytoma of the superior mediastinum 23 years after an initial complete resection. In the current biopsy specimen, the tumor cells were much more anaplastic than those seen 23 years ago. Although the patient was treated with chemotherapy, which consisted of ifosfamide and epirubicin, the tumor was unresponsive and he died 6 months later from disease progression. Careful long-term follow-up is mandatory for patients with hemangiopericytomas because recurrence with greater malignancy can develop following an extended disease-free interval.  相似文献   
992.
Objective: The effects of dose-escalation of 5-fluorouracil (5-FU) on the clinical outcome and pharmacokinetics of 5-FU were investigated in Japanese patients with Stage III/IVa esophageal squamous cell carcinoma.Methods: Thirty-five patients with Stage III/IVa were enrolled, who were treated with a definitive 5-FU/cisplatin-based chemoradiotherapy. A course consisted of continuous infusion of 5-FU at 400 mg/m2/day (the standard dose group, N=27) or 500-550 mg/m2/day (the high dose group, N=8) for days 1-5 and 8-12, infusion of cisplatin at 40 mg/m2/day on days 1 and 8, and radiation at 2 Gy/day on days 1 to 5, 8 to 12, and 15 to 19, with a second course repeated after a 2-week interval. Plasma concentrations of 5-FU were determined by high performance liquid chromatography at 5:00 PM on days 3, 10, 38 and 45, and at 5:00 AM on days 4, 11, 39 and 46.Results and conclusions: No patient with Stage IVa achieved a complete response in the standard dose group, whereas a complete response was observed at a rate of 50% in the high dose group, and this can be explained by a higher plasma concentration of 5-FU. The circadian rhythm in the concentrations found at the standard dose was not observed for a higher dose.  相似文献   
993.
BACKGROUND: The suitable parameter in PF as well as in serum that may predict the activity of endometriosis is not well described. Therefore, we tried to examine the peritoneal fluid (PF) and serum concentrations of hepatocyte growth factor (HGF) in different revised American Society of Reproductive Medicine (r-ASRM) staging and morphologic appearances of endometriosis in an attempt to determine whether HGF can be clinically useful to predict the activity of pelvic endometriosis. METHODS: Peritoneal fluid was collected from 137 women with endometriosis and 57 women without endometriosis during laparoscopy and blood sampling was collected from 37 women with endometriosis and 21 women without endometriosis before laparoscopy. The concentration of HGF in PF and serum was measured by enzyme-linked immunosorbent assay. The ability of isolated macrophages and stroma to secrete HGF in response to lipopolysaccharide (LPS) was evaluated. RESULTS: A significantly increased concentration of HGF in PF was found in women with endometriosis (1451.75 +/- 90.7 pg/mL) than that in non-endometriosis (1120.5 +/- 77.3 pg/mL, p < 0.01) without any remarkable difference in HGF levels between women with stage I-/II endometriosis and stage III-/IV endometriosis. When we distributed serum and PF levels of HGF according to different color appearances of endometriosis, we found a significantly higher serum and PF levels of HGF in women containing dominant red peritoneal lesions in pelvic cavity (740 +/- 109.3 pg/mL for serum; 1685 +/- 183.4 pg/mL for PF) than those having other pigmented lesions (649 +/- 79.5 pg/mL, p < 0.05 for serum; 1224 +/- 67.8 pg/mL, p < 0.05 for PF) or chocolate cysts (485 +/- 43.1 pg/mL, p < 0.05 for serum; 1118 +/- 83.1 pg/mL, p < 0.01 for PF). Exogenous stimulation with LPS significantly increased the production of HGF in the culture media by macrophages and stroma derived from women with endometriosis than that in women without endometriosis. CONCLUSIONS: These results suggest that women with early or advanced endometriosis as measured by r-ASRM scoring system are not associated with an increase in either serum or PF concentrations of HGF. Rather HGF levels in serum and PF were significantly increased in women harboring blood-filled red peritoneal lesions and may be clinically useful to predict the activity of pelvic endometriosis.  相似文献   
994.
Matsuda G  Hiraki K 《NeuroImage》2006,29(3):706-711
Traditional neuroimaging studies have mainly focused on brain activity derived from a simple stimulus and task. Therefore, little is known about brain activity during daily operations. In this study, we investigated hemodynamic changes in the dorsal prefrontal cortex (DPFC) during video games as one of daily amusements, using near infrared spectroscopy technique. It was previously reported that oxygenated hemoglobin (oxyHb) in adults' DPFC decreased during prolonged game playing time. In the present study, we examined whether similar changes were observed in children. Twenty children (7-14 years old) participated in our study, but only 13 of them were eventually subject to analysis. They played one or two commercially available video games; namely a fighting and a puzzle game, for 5 min. We used changes in concentration of oxyHb as an indicator of brain activity and consequently, most of the children exhibited a sustained game-related oxyHb decrease in DPFC. Decrease patterns of oxyHb in children during video game playing time did not differ from those in adults. There was no significant correlation between ages or game performances and changes in oxyHb. These findings suggest that game-related oxyHb decrease in DPFC is a common phenomenon to adults and children at least older than 7 years old, and we suggest that this probably results from attention demand from the video games rather than from subject's age and performance.  相似文献   
995.
Metastatic tumors in the stomach are rare. We report a case of solitary gastric metastasis from renal cell carcinoma (RCC) 19 years after radical excision of the primary tumor. During evaluation for anemia with melena, a small elevated tumor with ulceration was detected in the gastric fundus of this patient. The tumor was diagnosed as RCC based on endoscopic biopsy findings. There was no evidence of any other metastatic lesion, and a wedge resection of the stomach was performed. No additional metastasis or recurrence has been detected in the patient 12 months after discharge. This case confirms the existence of a very slow growing type of RCC with the potential for late solitary metastases and describes the surgical resectability.  相似文献   
996.
997.
BACKGROUND: Several clinical and epidemiological studies have observed a better outcome after sepsis in women than in men. The purpose of this study was to determine if these sex differences are observed in cytokine responses and the surface antigen expression of monocytes. In addition, the clinical courses of male and female patients after gastrointestinal surgery were compared. METHODS: A total of 25 patients with gastric carcinoma who underwent gastrectomy were enrolled in this study. Tumor necrosis factor-alpha (TNF-alpha), interleukin-10, and interferon-gamma (IFN-gamma) production by lipopolysaccharide-stimulated peripheral blood mononuclear cells (PBMCs) as well as the expression of Toll-like receptor-4 (TLR-4), TLR-2, human leukocyte antigen-D related (HLA-DR), and CD16 on monocytes in 16 men and 9 women on the day before surgery were compared with measurements on postoperative day (POD) 1. Furthermore, postoperative infectious complications, the development of systemic inflammatory response syndrome, and serum C-reactive protein levels on POD3 were compared. RESULTS: TNF-alpha production of PBMCs and TLR-2 and CD16 expression on monocytes were significantly higher in women than in men before surgery. IFN-gamma production of PBMCs and HLA-DR expression on monocytes were significantly lower in men than in women on POD1. Furthermore, TNF-alpha production of PBMCs on POD1 was significantly increased, and both IFN-gamma production and HLA-DR expression were significantly decreased compared with that observed before surgery in men, but no corresponding significant changes were observed in women. In addition, C-reactive protein levels on POD3 were significantly higher in men than in women. CONCLUSIONS: Both TNF-alpha and interleukin-10 production of PBMCs and both TLR-2 and CD16 expression on monocytes were significantly higher in women than in men on the day before surgery. Excessive TNF-alpha and suppressive IFN-gamma production of PBMCs, as well as a decrease in HLA-DR expression on monocytes, occurred more often in men than in women after surgery, suggesting that these factors all contribute to an increased susceptibility of men to develop systemic inflammatory response syndrome or postoperative infectious complications.  相似文献   
998.
The purpose of this study was to measure event-related potentials (ERPs) to clarify how attention affects neural activity during the visual perception of biological motion (BM). Thirteen healthy subjects observed BM or scrambled motion (SM). For SM, each point had the same velocity vector as in BM, but the initial starting positions were randomized. Each BM and SM was overlaid with ten noise dots and four rectangles. For the rectangles, one was or was not rotated 90 degrees relative to the others. Subjects were required to undertake two kinds of visual tasks. For the attention-to-motion condition, subjects directed their attention to the type of motion. For the attention-to-rectangle condition, subjects directed their attention to the rotational angle of the overlaid rectangles. As in our earlier study, the ERP response to the perception of BM had two negative components at approximately 200 ms (N200) and approximately 330 ms (N330) in both attentional conditions. Our analysis focused on the amplitude of the second negative component, which was sensitive to BM. There was a significant interaction between attention and the type of motion regarding the amplitude of N330. Specifically, the amplitude of N330 in response to BM was greater in the attention-to-motion condition than in the attention-to-rectangle condition, and was greater than the amplitude of the response to SM in the attention-to-motion condition. These results suggest that in this experimental design, processing of BM is modulated by attention.  相似文献   
999.
We report a rare case of a solitary primary paraganglioma arising in the mesentery, found in a 72-year-old woman who presented with abdominal pain and a palpable abdominal mass. This extra-abdominal paraganglioma developed from paraganglionic cells that travelled by vertebral migration from the root of the superior mesenteric artery. Extra-adrenal paraganglia extend anywhere from the neck down to the base of the pelvis. Ultrasonography, computed tomography (CT), and angiography showed a solid and cystic heterogeneously enhanced mass, which was fed by the superior mesenteric artery, without distant metastasis. Exploratory laparotomy revealed a large, dark, brownish-red mass in the mesentery of the ileum, which was distinct from the ileum. The mass consisted of peripherally solid areas with central hemorrhage and cystic degeneration. It was diagnosed as a paraganglioma histologically. The patient is free from recurrence of paraganglioma after 1 year of follow up. To our knowledge, this represents only the seventh case of a paraganglioma arising in the mesentery.  相似文献   
1000.
A 62-year-old man with renal cell carcinoma in the solitary kidney after right nephrectomy underwent CT-guided radiofrequency ablation. The tumor, which was located in the dorsal part of the lower aspect of the kidney, was exophytic and measured 2 cm in diameter. A 17-gauge, internally cooled radiofrequency needle electrode was placed percutaneously into the center of the lesion. Dynamic CT 6 days after the first ablation showed band-like residual lesion along the intact renal parenchyma. A second ablation was performed for the residual lesion. CT both 1 and 3 months after the second procedure demonstrated complete ablation with the normal renal parenchyma maintained.  相似文献   
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