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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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ABSTRACT

Purpose

To investigate the effect of 1% tropicamide on anterior chamber aqueous flare (ACAF) measurements acquired with laser flare meter in patients with pseudoexfoliation.  相似文献   
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Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types.  相似文献   
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OBJECTIVE: The uncinate process (UP) is an important anatomic landmark in frontal recess surgery. Its superior attachment shows great anatomic variability. The agger nasi (AN) cell is another important structure that affects frontal recess anatomy and there is a close neighborhood between them. The aim of this study was to investigate the relationship between superior attachment type of UP and the presence of AN cell. STUDY DESIGN: A retrospective anatomical study. METHOD: Computed tomography scans were evaluated of 486 sides of 243 patients who had had paranasal sinus. In 125 (26%) sides, the superior attachment of the UP could not be identified. In the remaining 361 (74%) sides, the prevalence of superior attachment of UP types and the presence of AN cell in each side were recorded. The results were evaluated with chi2 test. RESULTS: The AN cell was found in 290 (80.3%) of 361 sides. The prevalence of AN cell according to superior attachment of UP types were 79.6% for type 1/2, 90.1% for type 3, 71.4% for type 4, 86.5% for type 5, and 83.3% for type 6. The presence of AN cell according to superior attachment types of UP was not statistically significant (chi2= 3.54, P = 0.315). CONCLUSIONS: The AN cell was found to be present in 80.3% of the cases. However, the relationship between the presence of the AN cell and the superior attachment types of UP was not statistically significant.  相似文献   
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The present study evaluated99mTc(V) DMSA as an agent for the visualization of inflammatory lesions in comparison to99mTc(HI) DMSA and99mTc-HIG. All three radiopharmaceuticals were prepared with commercial kits.99mTc(V) DMSA was prepared at neutral pH by the addition of first bicarbonate and then pertechnetate to the kit contents. The labeling efficiency was 99% as determined by ITLC. Abscesses were induced by i.m. injection of 50 μl turpentine into the right thighs of 36 Swiss albino mice. Six days later 3.7 MBq of each radiopharmaceutical was i.v. administered to 12 mice. The mice were sacrificed at 1,3,6 and 24 h later. Scintigrams were obtained with a gamma camera. The abscesses were better visualized on scintigrams with99mTc(V) DMSA compared to99mTc(III) DMSA, starting at 1 h. The animals were dissected and the organs were removed, weighed and the radioactivity determined with a gamma counter. The abscess to other tissue ratios were higher with99mTc(V) DMSA than the other radiopharmaceuticals. The max. abscess/muscle ratios were 9.46 ± 3.20 (24 h), 4.19 ± 1.39 (6 h) and 5.98 ± 1.17 (24 h) and max. abscess/blood ratios were 6.22 ± 1.41, 4.09 ± 0.84 and 0.914 ± 0.351 all at 24 h for99mTc(V) DMSA,99mTc(III) DMSA and99mTc-HIG, respectively. Experimental arthritis was produced in 6 New Zealand white rabbits by intra-articular injection of ovalbumin. Four days later 37 MBq of99mTc(V) DMSA and99mTc-HIG were each i.v. administered to 3 rabbits. Scintigrams obtained at 1, 3, 6, and 24 h clearly demonstrated arthritic joints. ROFs over arthritic joints were compared to contralateral normal joints (A/C). The max. A/C ratios were 2.10 ± 0.31 (3 h) and 2.92 ± 0.99 (24 h) for99mTc(V) DMSA and99mTc-HIG, respectively. Our results indicated the feasibility of imaging inflammatory lesions with99mTc(V) DMSA.  相似文献   
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Background: Among gastric restrictive operations, the procedure of choice is still controversial. The aim of this study is to compare the results of two different gastric restrictive procedures: vertical banded gastroplasty (VBG) and stoma adjustable silicone gastric banding (ASGB). Methods: Between 1991 and 1996, 51 patients were treated surgically for morbid obesity: 27 underwent VBG and 24 underwent ASGB. Preoperative body weight (BW), body mass index (BMI) and percentage of ideal body weight (% IBW) were (mean ± SD): 145.7 ± 45.3 kg; 53.9 ± 15.9 kg/m2; 249.1 ± 73.5% respectively in the VBG group. Corresponding figures for the ASBG group were 132.5 ± 22.7 kg; 46.9 ± 7.8 kg/m2 and 207.2 ± 35.0%. Results: In the VBG group, the median follow-up period was 26 months (range: 7-47). Eighteen months after the operation BW, BMI, % IBW and percentage of excess weight loss (% EWL) were 85.5 ± 26.8 kg, 31.9 ± 9.8 kg/m2, 145.4 ± 43.9% and 74 ± 1% respectively. Complications included incisional hernia (n = 1), and bowel obstruction (n = 1). One patient died of acute myocardial infarction on the third postoperative day. In the ASGB group, median follow-up time was 19.7 months (range: 18-26). At 18 months postoperation BW, BMI, % IBW and % EWL values were 86.6 ± 20.6 kg 30.6 ± 6.6 kg/m2 140.6 ± 29.3% and 64 ± 1% respectively. Gastric wall erosion occurred in two patients and the bands had to be removed. These patients underwent VBG 6 months later. Complications encountered in this group were incisional hernia (n = 1), outlet stenosis and reflux esophagitis (n = 1), reservoir leakage (n = 1) and gastrointestinal bleeding (n = 1). Two patients died of pulmonary embolism and acute gastrointestinal bleeding. Conclusions: Weight reduction was not statistically significant between the two groups. ASGB was easier to perform and less invasive than VBG.  相似文献   
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