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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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A survey of 2576 children aged two to nine years was carried out in Dhaka, Bangladesh, as part of a collaborative study to test the validity of a questionnaire (the Ten Questions) for screening severe childhood disabilities in community settings. Approximately 7% of the children were positive on the screen and this rate was slightly higher in boys than girls. The sensitivity, specificity and negative predictive value of the Ten Questions were perfect or nearly perfect for severe and moderate (serious) disabilities. The positive predictive value was only 22% for serious disabilities, but 70% of children classified as false positives were found to have mild disabilities or other conditions (such as ear infections) for which early detection and treatment could be beneficial. No major age or gender differences in the validity of the questionnaire were apparent, but this finding needs additional study and confirmation with studies based on larger samples. In general, the results indicate that the Ten Questions is a valid tool for screening serious disabilities in children and can potentially improve the efficiency of health services by reducing the number of children requiring attention from professionals. Future studies using the Ten Questions should foster greater attention to the dimensions of childhood disability as a public health problem in the less developed world.  相似文献   
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OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.  相似文献   
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Over a five-year period, 197 hysterectomies were performed at King Khalid University Hospital (KKUH). Indications for the procedures vary from menstrual disorders and symptomatic fibroids to ovarian malignancy. The most common indication was found to be menorrhagia. Among multiple pre-operative indications, only the first listed major indication for hysterectomy was chosen. There were 145 abdominal and 52 vaginal hysterectomies and all were elective gynaecological procedures, majority of which were performed on women in their fourth and fifth decades of life. Verification of pre-operative diagnosis, when correlated with pathological findings, showed that some of the indications for the procedure deserve a more critical reappraisal. Since hysterectomy carries substantial economic and medical consequences, indications for undertaking the procedure deserve more careful scrutiny given the surgical and nonsurgical options that are currently available. There may be a need, therefore, to assess the appropriateness or otherwise of the use of hysterectomy in many of the patients in future.  相似文献   
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The MS-2 is an instrument for rapid automated testing of antimicrobial susceptibility. Its performance was evaluated by comparison with disc diffusion and MIC tests in a collaborative study in four European laboratories. Tests on independently isolated organisms showed the MS-2 to be in essential agreement with conventional methods in 94.8% of tests. A further series of 170 welldefined pathogens for which a reference antibiogram was available were tested by MS-2 and the manual methods in all of the participating laboratories. MS-2 results were in full accord in 90 % of tests and in essential agreement in 94 %. MS-2 results compared at least as well with the reference values as did either of the manual methods. Initial problems of false susceptibility results with erythromycin and penicillin were resolved by (1) the addition of small amounts of erythromycin which acted as an inducer and (2) by the use of a low content penicillin disc. MS-2 was found to be reliable and needed no attention following loading of the test cuvette cartridges. A print-out of the results was available 2–5 h after inception of the test.  相似文献   
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Objective: To report a case of typhoid fever contracted in Portugal in 1994 due to a Salmonella typhi isolate which had reduced susceptibility to fluoroquinolone (MIC 1 mg/L of ciprofloxacin) and high level resistance to nalidixic acid (MIC ≥56 mg/L).
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi.  相似文献   
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