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81.
PURPOSE: Many studies have shown that the S-phase fraction is a reflection of the proliferation potential of tumors, and DNA aneuploidy is more common in malignant tumors. In this preliminary study, the authors assessed the Tc-99m MIBI uptake of brain tumors and its relation to tumor grade and DNA content of the tumor cells. METHODS: Ten patients (eight male, two female; mean age, 53.2 +/- 6.11 years) with untreated brain tumors were included in the study. SPECT imaging was performed 20 minutes after injection of 740 MBq (20 mCi) Tc-99m MIBI. A single detector camera with a low-energy high-resolution collimator was used for image acquisition. A region of interest was drawn in the tumor area under magnetic resonance guidance. A Tc-99m MIBI uptake index was computed as the mean tumor-to-background ratio. Flow cytometric analysis of fresh tumor tissue specimens was performed immediately. The percentages of cells in the G0/G1, S, and G2/M phases were determined for each patient. RESULTS: DNA aneuploidy was found in 4 (49%) patients, whereas diploidy was found in 6 (60%) patients. There was a significant positive correlation between the Tc-99m MIBI uptake and the percentage of the S-phase fraction of the cell cycle ( = 0.000, r = 0.95). The Tc-99m MIBI index was significantly greater in aneuploid tumors than in diploid tumors ( < 0.01). CONCLUSIONS: High-grade brain tumors have increased Tc-99m MIBI uptake compared with that of low-grade tumors. Tc-99m MIBI uptake is correlated with the percentage of the S-phase fraction of the cell and the aneuploidy level of the brain tumor. This preliminary report suggests that Tc-99m MIBI imaging may be useful in the evaluation of the biologic characteristics of brain tumors. 相似文献
82.
Protective effect of IGF-1 on experimental liver cirrhosis-induced common bile duct ligation 总被引:9,自引:0,他引:9
Cantürk NZ Cantürk Z Ozden M Dalçik H Yardimoglu M Tülübas F 《Hepato-gastroenterology》2003,50(54):2061-2066
BACKGROUND/AIMS: The causes of malnutrition in liver cirrhosis are multifactorial. Levels of IGF-1 (insulin like growth factor-1) that is a crucial regulator of intermediary metabolism decreases. The aim of this study was to analyze the effect of IGF-1 supplementation during liver cirrhosis induced by common bile duct ligation. METHODOLOGY: Rats were divided into five different groups: One sham and four experimental groups. Rats in three of four groups were treated with 2 micrograms/day IGF-1 with a different time of experiment in each group. Blood biochemical parameters, tissue malondialdehyde, glutathione levels and the activity of tissue antioxidant enzymes and conventional and immunohistochemical analysis of liver samples were studied for each group. RESULTS: Serum albumin, total protein, fibrinogen levels decreased and prothrombin time was prolonged in the bile duct ligated and transected experimental group but not in the IGF-I treated rats compared with the rats in sham group. Liver malondialdehyde levels significantly increased in control group but not in IGF-1 treated groups. The activities of antioxidant enzymes were decreased compared with the other groups. Histopathology findings of liver biopsy demonstrated intense degree fibrosis and overexpression of fibroblast growth factor and desmin in the control group but a lesser degree of those in the IGF-1 treated groups. CONCLUSIONS: IGF-1 treatment improves liver function and decreases oxidative liver damage and histopathological findings. Further studies are required to delineate the mechanisms of protective effects of IGF-1. 相似文献
83.
Deeply seated aggressive fibromatosis also termed as desmoid tumors are rare tumors that invade surrounding structures. Although they never metastasize mortality rate may be as high as 10% due to their aggressive local behavior. Intraabdominal desmoid tumors are usually associated with familial poliposis coli and have a high recurrence rate regardless of the therapy instituted. Sporadic cases are very rare and generous surgical excision may be of benefit. We hereby report 2 siblings with sporadic pancreatic desmoid tumors who also harbor additional fibrotic masses in the pelvis. Although in previously reported cases there is usually a triggering event such as trauma, in the present cases there was no inciting event. Furthermore, the cases are without an associated FAP history, which provides the first clinical clue of a possible genetic determinant in this rare disorder. 相似文献
84.
85.
86.
Ureteroscopy and pneumatic lithotripsy, followed by extracorporeal shock wave lithotripsy for the treatment of distal ureteral stones 总被引:1,自引:0,他引:1
Zafer Gökhan Gurbuz Murat Gonen Adem Fazlioglu Habib Akbulut 《International journal of urology》2002,9(8):441-444
BACKGROUND: We retrospectively reviewed our experience with retrograde ureteroscopy (URS) and a pneumatic lithotriptor in 160 patients with distal ureteral stones to determine whether prior extracorporeal shock wave lithotripsy (ESWL) is a limiting factor in the ureteroscopic procedure. METHODS: From January 1999 to September 2000, we performed URS and pneumatic lithotripsy in 160 patients with distal ureteral stones. Seventy-four patients were treated with URS primarily (Group 1), while the remaining 86 patients received URS only after ESWL had failed (Group 2). For URS and lithotripsy, we used a 9.5 French rigid instrument and vibrolith (Elmed, Ankara, Turkey). RESULTS: In Group 1, 73 of 74 patients (98.6%) were treated successfully by URS alone, as were 81 of 86 patients (94.4%) in Group 2. Impacted stones were also observed in 17 patients from Group 2. In these patients, endoscopic observation revealed edematous inflammation above and below the calculus. Ureteral perforation occurred in one patient from Group 2, which required surgical repair. There was no significant difference in the stone-free rates of the two groups t = 1.4 < 1.96t( infinity,0.05). CONCLUSION: Our data demonstrate that when ESWL fails, URS and pneumatic lithotripsy is as safe and effective as primary URS. Pneumatic lithotripsy also seems to be an effective treatment modality for impacted stones. 相似文献
87.
Ilkay Koray Bayrak Zafer Ozmen Mehmet Selim Nural Murat Danaci Baris Diren 《Korean journal of radiology》2008,9(3):250-257
OBJECTIVE: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the use of a lower concentration (0.5 M). A higher concentration would also cause a reduction in dose. The purpose of our study was to test the use of a low dose (0.05 mmol/kg) of gadobutrol in magnetic resonance renography and angiography and compare the findings with a dose of 0.1 mmol/kg. MATERIALS AND METHODS: One-hundred-thirty-four patients referred for magnetic resonance angiography for suspected renovascular disease participated in the study. Contrast enhanced MR renography and angiography were performed after administration of a bolus of 0.1 mmol/kg or 0.05 mmol/kg gadobutrol in randomized patients. The relative signal intensity-time curves of the aorta, peripheral cortex and parenchyma, were obtained. Two radiologists evaluated the angiographic images and evaluated the quality of angiography. RESULTS: The signal intensity with a low dose of gadobutrol was significantly lower in early phases, in the peripheral cortex (for 36, 54, 72 and 90 seconds), the parenchyma (for 36, 54, 72 seconds) and the aorta (for 18, 36, 54, 72 seconds). The decreases in the early phase obtained with a low dose of gadobutrol caused blunter time intensity curves. The difference in the quality scores of the readers for the angiographic images for the use of the two different doses was not statistically significant (p > 0.05). CONCLUSION: A lower dose of gadobutrol can be used for MR renal angiography, but for MR renography the normal dose should be used. 相似文献
88.
Mehmet Turgut
sman Ekin Ozcan Can Zafer Karaman 《Journal of Medical Imaging and Radiation Oncology》1998,42(3):262-263
Clinical, radiographic, and operative findings in two children with intra-osseous pseudomeningocele of the occipital bone due to cranial trauma are presented here, along with a literature review of this uncommon radiologic entity. 相似文献
89.
Tancan Uysal Zafer Sari 《American journal of orthodontics and dentofacial orthopedics》2005,128(2):226-230
INTRODUCTION: The aims of this study were to determine the size of individual permanent teeth, tooth-size ratios for the maxillary and mandibular dentitions, and sex differences for those variables in a Turkish population, and to compare the figures obtained with those of the Bolton analysis. METHODS: The data were derived from dental casts of 150 Turkish subjects (72 men, mean age 22.09 +/- 3.11 years; 78 women, mean age, 21.11 +/- 2.08 years) with normal occlusions. The mean, standard deviation, and minimum and maximum values were calculated for individual tooth size, and overall and anterior ratios, separately for men and women. To determine whether there are sex differences in intermaxillary tooth size discrepancies, an independent samples t test was performed. RESULTS: The mesiodistal dimensions of the maxillary teeth showed greater variability than the mandibular teeth, with the first molar dimensions having the greatest variability. The overall and anterior ratios were found to be 89.88 +/- 2.29 and 78.26 +/- 2.61, respectively. A statistically significant sex difference was found only in overall ratio (P < .001). According to Bolton's mean values, a discrepancy in the overall ratio was found in 18% of Turkish normal occlusion subjects, and anterior ratios outside 2 standard deviations from the Bolton mean were found in 21.3% of our sample. CONCLUSIONS: These findings indicate that population-specific standards are necessary for clinical assessments. Bolton's original data do not represent Turkish people, and therefore it is appropriate to use Turkish norms in daily orthodontic practice for Turkish patients. 相似文献
90.
Erol KOC Mustafa TUNCA Emin Ozgur AKGUL Ahmet AKAR Yasemin KURT Zafer KURUMLU Kemal ERBIL Selim KILIC 《The Journal of dermatology》2009,36(4):191-196
Neopterin is an immunological marker of cellular immune activation. Etanercept is a tumor necrosis factor-α (TNF-α) antagonist that decreases excessive levels of TNF-α associated with inflammatory disease down to physiological levels. The objective of this study was to investigate urine neopterin levels in psoriatic patients treated with etanercept, to study the effect of etanercept as a TNF-α blocker on urine neopterin levels. Urine neopterin levels and urine neopterin/creatinine ratios were measured by high-performance liquid chromatography in 22 patients with psoriasis before and after treatment with etanercept. Results were compared with a group of 20 healthy volunteers, and 20 patients with inflammatory skin diseases as control groups. Urine neopterin levels, neopterin/creatinine ratios and Psoriasis Area and Severity Index (PASI) scores were evaluated at baseline, and the 12th and 24th week after treatment. Urine neopterin levels were significantly elevated in the psoriatic group compared with control and inflammatory skin diseases groups ( P < 0.05). Urine neopterin levels were significantly reduced after etanercept treatment. Statistically we did not find any correlation between neopterin levels and PASI scores. Our findings indicate that urine neopterin concentrations may reflect the disease activity in psoriasis, and may be used as a marker for monitoring disease activity and response to treatment with etanercept in psoriatic patients. 相似文献