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1.
Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.  相似文献   
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During the diagnostic evaluation of patients with vasculogenic impotence duplex scanning has been proposed as a reliable noninvasive method to evaluate the cavernous arteries. However, the sensitivity and specificity of this test have never been elucidated. To provide insight into the clinical value of this test 25 men who presented with impotence and failed to respond to 60 mg. intracavernous papaverine were evaluated with duplex scanning and the results of this modality were compared to penile angiography. The cavernous arteries were considered normal by duplex scanning if the artery demonstrated either a 60% or greater increase in diameter and/or a peak flow velocity of greater than 25 cm. per second 5 minutes after papaverine injection. Penile angiography was considered normal if both cavernous arteries were visualized and appeared to be normal radiographically (after intracorporeal papaverine). In the 25 patients studied there was no significant difference in peak flow velocity between patients with normal or abnormal cavernous arteries by angiography. In addition, arterial dilatation (more than 60%) after papaverine injection did not correlate with the results of the angiogram. These data demonstrate that duplex scanning of the cavernous arteries does not correlate well with what is observed by penile angiography in a selected population of men with vasculogenic erectile dysfunction. Since penile angiography itself has limitations in the evaluation of the penile arteries, the reliability of duplex scanning to identify cavernous artery dysfunction needs additional confirmation.  相似文献   
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We examined whether the inhibition of neoplastically transformedcell growth by co-cultured non-transformed cells involved gapjunctional intercellular communication (GJIC). The growth ofpoorly communicating (  相似文献   
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Probucol is a lipid-lowering agent with an antioxidant effect; however, its influence on the liver remains unclear. The effects of probucol on hyperlipidemic rabbit liver are investigated to add a structural data on its therapeutical profile. Local albino rabbits were divided into three groups. 1) Hyperlipidemic group: fed with 1% cholesterol (150 g/kg/day) enriched chow for 2 months. 2) Probucol treated group: group 1 + intraperitoneal probucol (10 mg/kg/day) administration for 15 days. 3) Control group fed with normal chow. The blood lipid profile was investigated biochemically. Liver samples were examined electronmicroscopically. Within the parenchymal cells of group 1, the amount of rough surfaced endoplasmic reticulum was increased, its cisterna was dilated displaying a moderately electron dense substance in it and showed close apposition with the condensed mitochondria. In group 2, smooth surfaced endoplasmic reticulum was in extensive amounts filling almost all of the cytoplasm, displayed a reticular, degenerated appearance and was in close relation with the condensed, degenerated mitochondria. Probucol may cause degenerative changes on the liver parenchyme at the subcellular level. It alters the structure of these cells mainly acting on the smooth surfaced endoplasmic reticulum and the mitochondria that are known to be involved in cellular detoxification.  相似文献   
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PURPOSE: To report five patients with intraocular invasion of conjunctival squamous cell carcinoma and to make recommendations regarding clinical recognition and treatment of this condition. METHODS: The authors reviewed the clinical records and pathology slides on five patients who had intraocular invasion of conjunctival squamous cell carcinoma, and they describe the presenting features and histopathology in these cases. RESULTS: Intraocular invasion of conjunctival squamous cell carcinoma occurred in older patients who had one or more recurrences of a previously excised conjunctival epithelial tumor located near the comeoscleral limbus. The intraocular recurrence often was heralded by the onset of low-grade inflammation and secondary glaucoma, simulating a granulomatous iridocyclitis. A white mass generally was observed in the anterior chamber angle. Histopathologic examination revealed an ingrowth of malignant epithelial cells through the limbus with diffuse involvement of the anterior segment of the eye. The reported patients were managed by modified enucleation (standard enucleation with excision of affected conjunctival tissue). Metastatic disease did not develop in any of the patients. CONCLUSIONS: The onset of signs of uveitis and glaucoma and a white mass in the anterior chamber angle in a patient with prior excision of a conjunctival squamous cell neoplasm tumor should raise suspicion of intraocular recurrence of conjunctival squamous cell carcinoma. Most affected patients require enucleation or subtotal orbital exenteration. The prognosis is good.  相似文献   
8.
Giant cell reparative granuloma of the orbit   总被引:1,自引:0,他引:1  
PURPOSE: To report a case of giant cell reparative granuloma occurring in the orbit and to discuss its clinical, radiologic, and histopathologic characteristics in contrast with other similar lesions. METHODS: A 38-year-old man developed pain and mild proptosis of the left eye. Computed tomography and magnetic resonance imaging demonstrated an intraosseous cystic orbital mass. Excisional biopsy disclosed giant cell reparative granuloma of the orbit. RESULT: At 11 months' follow-up, the patient had normal vision, with no tumor recurrence. CONCLUSION: Giant cell reparative granuloma of the orbit is a rare benign fibro-osseous proliferation that is generally seen in young adulthood. It should be considered in the differential diagnosis of orbital fibro-osseous proliferation. Surgical excision and curettage is the therapeutic method of choice.  相似文献   
9.
To understand further the role of trace elements in the pathogenesis of febrile convulsions, serum zinc (Zn), copper (Cu), magnesium (Mg) and CSF Zn, Cu, Mg and protein levels were measured by spectrometry in patients with febrile convulsion (n=19), bacterial meningitis (n=9), viral CNS infection (n=16) and in the control groupn=10) which consisted of children with signs of meningeal irritation due to upper respiratory tract infection but normal CSF findings. Samples were obtained within 6 h after admission to hospital. Mean serum and CSF Zn levels in the febrile convulsion group were significantly lower than in the other groups (for serum Zn: 0.66±0.03 mg/l vs 0.98±0.07 mg/l, 1.06±0.08 mg/l, 1.05±0.09 mg/lP<0.05; for CSF Zn: 22.96±1.62 g/l vs 75.47 ±6.9 g/l, 50.32±5.235 g/l, 39.85 ±2.81 g/lP<0.05). A linear relationship was established between serum Zn and CSF Zn levels (P<0.001). Mean CSF Zn, Cu and protein levels in the bacterial meningitis group were significantly higher than in the other groups (for CSF Cu 63.94±6.33 g/l vs 38.77±2.70 g/l, 35.84±3.48 g/l, 33.86±2.88 g/lP<0.05; for CSF protein 0.80 ± 0.12 g/l vs 0.22±0.02 g/l, 0.53±0.08 g/l, 0.19±0.01 g/lP<0.05). In children with meningitis, the elevation of the mean CSF Zn and Cu levels may result from the breakdown of the blood-brain barrier and subsequent leakage of trace elements and protein from serum to CSF. There was no significant difference between the four groups in terms of mean serum Mg and mean CSF Mg levels.Conclusion Serum and CSF Zn levels are decreased in children with febrile seizures. Zinc deprivation may play a role in the pathogenesis of febrile seizures.  相似文献   
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