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OBJECTIVE: The purpose of this study was to determine whether the addition of positron emission tomography (PET) with the radiotracer FDG to cross-sectional imaging, such as CT, increases accuracy in the detection of tumor spread. SUBJECTS AND METHODS. Fifteen patients who were thought to have ovarian cancer on the basis of the results of physical examination, sonography findings, and level of serum cancer antigen 125 were enrolled over an 11-month period. After screening, patients underwent two imaging examinations-abdominopelvic CT and whole-body FDG PET- within 2 weeks before surgery. Also before surgery, staging accuracy was assessed separately using CT with or without FDG PET (which was based on modifications of the International Federation of Gynecology and Obstetrics [FIGO] criteria). The results of the histology and surgery findings were used to assess the accuracy of the scanning findings. RESULTS: Staging revealed stage III disease in seven patients (IIIC, n = 6; IIIB, n = 1), stage II in three (IIC, n = 2; IIB, n = 1), and stage I in five (IC, n = 3; IA, n = 2), according to the FIGO criteria. Although CT staging correlated with postoperative staging in eight (53%) of 15 patients, consensus evaluation of CT with FDG PET staging improved correlation with postoperative staging in 13 (87%) of 15 patients. CONCLUSION: The addition of FDG PET to CT increases accuracy in staging of ovarian cancer.  相似文献   
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OBJECTIVE: To evaluate the effect of inputs estimated from different methods for metabolite correction on binding potential (BP) of C-flumazenil (FMZ). METHODS: Five healthy volunteers underwent C-FMZ positron emission tomography. Arterial blood was sampled to obtain plasma radioactivity and metabolite fraction, followed by estimation of input functions with several methods. Binding potential images for different input functions and that using the noninvasive graphic method were calculated. Images of standardized uptake value (SUV) with different acquisition times were also compared. RESULTS: Binding potential images calculated from arterial inputs were almost equivalent, and regional values were not significantly different irrespective of methods for metabolite correction as well as the noninvasive graphic plot method. Standardized uptake value images showed less contrast compared with quantitative BP images, and the regional values varied depending on scan time. Statistical parametric mapping analysis showed significant regional differences between BP and SUV images. CONCLUSION: Binding potential images were equivalent irrespective of calculation methods; however, SUV was not appropriate for quantitative evaluation.  相似文献   
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Purpose To determine whether fibril length is correlated with graft healing as well as cellular and capillary ingrowth in a canine carotid implantation model.Methods Expanded polytetrafluoroethylene (ePTFE) vascular grafts with three different fibril lengths (30, 60, and 90µm) were implanted into the carotid artery in dogs. They were retrieved 4 weeks later, and subjected to histomorphometric analysis.Results Endothelial healing was best in the 60-µm grafts. Not only cellular ingrowth but also capillary ingrowth was most evident in the 60-µm grafts, followed by the 90-µm grafts and then the 30-µm grafts.Conclusion Better endothelial healing of ePTFE vascular grafts is correlated with more cellular and capillary ingrowth, but more cellular and capillary ingrowth is not correlated with longer fibril length or higher air porosity.  相似文献   
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Patients suffering from traumatic intracranial hemorrhage (TICH) may experience an episode of catastrophic intraoperative hypotension (IHT), after decompression of the brain. The aim of this study was to investigate the risk factors for IHT during emergency craniotomy A total of 67 patients, who underwent emergency craniotomy due to TICH, were divided into two groups: IHT ( n=31 ) or without IHT ( n=36 ). Data concerning (1) age; (2) gender; (3) mechanism of injury; (4) Glasgow Coma Scale (GCS) on admission; (5) abnormality of the pupils (anisocoria or mydriasis); (6) mean arterial blood pressure; (7) heart rate; (8) time elapsed before craniotomy from injury; (9) initial brain CT scans; (10) duration of craniotomy; and (11) total infusion or urine volume until craniotomy were collected prospectively as IHT risk factors. Low GCS score (<5), tachycardia (heart rate >112min(-1)) and hypertension (mean blood pressure >131mmHg) before emergency craniotomy were strongly ( P<0.05 ) associated with IHT. Delayed surgery (>173min until craniotomy) also had a significant ( P<0.005 ) effect on IHT. The risk factors for IHT were considered as a low GCS score on admission, tachycardia, hypertension before emergency craniotomy and delayed surgery. These results suggested the patients with IHT had a high sympathetic tone before emergency craniotomy A sudden reduction in sympathetic tone after surgical decompression of the brain might cause IHT. We concluded that an important factor in the occurrence of IHT was not only the injury severity, but also the balance between sympathetic and parasympathetic activity before decompression surgery.  相似文献   
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To evaluate methotrexate (MTX) administration as a conservative treatment for ectopic pregnancy, we reviewed the medical records of 248 cases (210 patients) of MTX treatment for tubal pregnancies at our department between December 1985 and December 2003, and compared its pregnancy prognosis with that of laparoscopic salpigotomy (59 patients). With the MTX treatment, 185 patients were successfully treated, and the subsequent pregnancy rate and ectopic pregnancy rate were 48.4 % and 18.4 %, respectively, while those rates were 49.2 % and 18.6 %, respectively, after the salpigotomy. These results suggest that MTX treatment is comparable to the more conservative operation. To clarify the (dys/) function of the ectopic implantation tubes and MTX-treated tube (s), we excluded patients who had a contra-lateral healthy tube, and extracted 40 patients as "the affected tube group", where the pregnancy-related parameters were not adversely affected. The findings suggest that MTX is not necessary to preserve tubal function.  相似文献   
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Renoprotective effects of omapatrilat are mediated partially by bradykinin   总被引:2,自引:0,他引:2  
AIM: To investigate the effects of omapatrilat on systemic and renal hemodynamics, glomerular dynamics, renal function, and histopathological changes as well as the participation of the bradykinin B2 receptor in WKY, SHR, and L-NAME/SHR rats. METHODS: Eight groups of 17-week-old rats were examined using renal micropuncture techniques and histopathological analyses after 3 weeks of treatment: group 1, WKY control; group 2, WKY+omapatrilat (40 mg/kg/day); group 3, SHR control; group 4, SHR+omapatrilat; group 5, SHR+L-NAME (50 mg/l); group 6, SHR+L-NAME+omapatrilat; group 7, SHR+L-NAME for 3 weeks followed by omapatrilat for a subsequent 3 weeks, and group 8, SHR+L-NAME+omapatrilat+bradykinin antagonist icatibant (500 microg/kg/day). RESULTS: In WKY and SHR, omapatrilat significantly reduced the mean arterial pressure, increased effective renal blood flow and single nephron plasma flow associated with reduced glomerular arteriolar resistances. Furthermore, omapatrilat prevented and reversed L-NAME induced urinary protein excretion, glomerular and arteriolar injuries, glomerular morphometric alterations, and glomerular apoptosis (at least, p < 0.05). Icatibant partially inhibited these beneficial effects of omapatrilat. CONCLUSION: Omapatrilat provided potent antihypertensive and renoprotective actions, which were mediated, in part, by bradykinin.  相似文献   
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