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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   
2.
Conclusions: This study revealed a significant correlation between red-green-blue (RGB) values of tympanic membrane (TM) images and the presence of effusion in the middle ear. These results confirm that endoscopic RGB evaluation is a rapid and non-invasive procedure yielding objective results. Objective: To investigate, in cases of otitis media with effusion (OME), the correlation of the TM color changes with the presence and viscosity of the effusion in the middle ear. Methods: Endoscopic images of the TMs of 52 patients (group 1) and 52 healthy controls (group 2) were taken during their otologic examinations. RGB values of particular points were measured on the TM images of both groups. Additionally, in group 1 the viscosity of each effusion taken by paracentesis during surgery was also measured intraoperatively with a viscometer. Patients with viscosity values lower and higher than 450 cP (centipoise) were subdivided into groups 1a and 1b, respectively. Results: Study and control groups were comparable regarding the number of patients and their mean ages (p > 0.05). Statistically significant differences were found in RGB values of the TM between groups 1 and 2, but not between groups 1a and 1b.  相似文献   
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The in vivo effects of non-steroidal anti-inflammatory drugs (NSAIDs) on the host immune system are still poorly understood. However, through inhibition of prostaglandin synthesis, NSAIDs may exhibit immunomodulating properties. The present work was aimed at evaluating the influence of niflumic acid on immune responses when administered orally for 7 consecutive days to 8-week-old inbred mice. Immunological tests were performed 24 h after the arrest of the treatment. At a dosage of 50 mg/kg/day, niflumic acid exerted noticeable immunostimulating effects, as shown by an increase in plaque-forming cell numbers after in vivo immunization with sheep red blood cells, an augmentation of spleen cell proliferation responses to stimulation with T- or B-cell mitogens and of T-cell cytotoxic response to allogenic cells. Phagocytosis-induced chemiluminescence of peritoneal macrophages was also enhanced whereas interleukin-1 production by these cells was depressed, but without concomitant modification in interleukin-2 production by T-cells. Increasing the niflumic acid dosage to 75 mg/kg resulted in the disappearance of the immunostimulatory effects on lymphocytes responses. Macrophage activities were affected similarly in mice receiving 50 mg/kg. These results demonstrate that niflumic acid is able to stimulate in vivo several immunological functions and, consequently, to maintain host immune defenses. Interestingly, it depressed interleukin-1 production, known to play a major role in the inflammatory process.  相似文献   
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The stability of misoprostol oil is significantly improved in a hydroxypropyl methylcellulose (HPMC) dispersion (1:100). In order to assess the effect of water on misoprostol stability, the rate of misoprostol degradation was investigated in the misoprostol/HPMC dispersion at 55°C, along with the water sorption isotherm, under seven different relative humidity (RH) conditions ranging from 0 to 81%. The results indicated that the first-order rate constants of misoprostol degradation increased in a concave-up fashion as the water content of the dispersion increased. Below 30% relative humidity (2% water), the first-order rate constants of misoprostol degradation were found to be minimum. The results of the stability study were interpreted in terms of the changing structure of HPMC as it related to the mobility of water and misoprostol within the HPMC dispersion.  相似文献   
7.
Whether a flap can be raised successfully in a body region that has been subjected to burn injury remains an issue. The aim of this study was to investigate the survival of skin flaps that were elevated after superficial and deep partial-thickness burn injury in a rat model. Sixty-five rats were divided into five groups: Group 1 (N = 15) was the control group, group 2 (N = 10) included rats with superficial partial-thickness burns that had flaps elevated on day 0, group 3 (N = 15) was comprised up of rats with superficial partial-thickness burns that had flaps elevated on day 4, group 4 (N = 10) included rats with deep partial-thickness burns that had flaps elevated on day 0, and group 5 (N = 15) was comprised of rats with deep partial-thickness burns that had flaps elevated on day 4. Caudally based dorsal flaps consisting of skin and panniculus carnosus were elevated in all groups, and the amount of surviving tissue on each flap was quantified. The surviving areas of flaps elevated on postburn days 0 and 4 in superficial partial-thickness burn zones (groups 2 and 3) were larger than those of flaps that were elevated on postburn days 0 and 4 in deep partial-thickness burn zones (groups 4 and 5). The surviving portions of flaps that were elevated on day 4 in superficial partial-thickness burn zones (group 3) were similar to the surviving areas of flaps in the control group (group 1), and were larger than those of all other groups (groups 2, 4, and 5). In this rat model, flaps were elevated in superficial dermal burn zones with successful outcomes. However, raising flaps in deep dermal burn zones was not a reliable method.  相似文献   
8.
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   
9.
The fingertip is an extremely intricate area of digital sensibility that plays an important role in fine perception and hand function. Thus, sensate fingertip reconstruction is essential to the recovery of most hand functions. The authors used two methods of direct-flow homodigital neurovascular island flap coverage to reconstruct distal finger amputations-namely, the triangular-advancement flap technique and the step-advancement flap method. The authors present their experience with these two variations of direct-flow homodigital neurovascular island flaps and their use in reconstructing 18 fingertips and 7 proximal amputation stumps. They did not observe flap failure, and they achieved stable, well-vascularized, appropriate-thickness skin coverage with good sensory properties in all patients. However, they found that the triangular-advancement flap technique was easier to plan and perform than the step-advancement method.  相似文献   
10.
This case report describes a rare complication of unicompartmental knee arthroplasty. Femoral fracture after TKR is a serious and relatively common problem, but to the best of our knowledge, only one case of femoral condylar fracture after UKA has been reported thus far.  相似文献   
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