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排序方式: 共有2587条查询结果,搜索用时 15 毫秒
1.
Senem Maral Muradiye Acar Ozlem Sahin Balcik Eyyup Uctepe Omer Faruk Hatipoglu Derya Akdeniz Hatice Uludag Altun Ali Kosar Mehmet Gunduz Esra Gunduz 《Medicine》2015,94(16)
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.
We report a case of recurrent calculi in a Kock pouch continent urinary diversion. An open operation was avoided by successfully excising the Marlex mesh and removing it with the associated calculi in an endoscopic fashion. 相似文献
3.
Esra Baltacio?lu Ferda Alev Akalin Eda Topalo?lu Erkan Süküro?lu Umit Cobano?lu 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):803-808
Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease. 相似文献
4.
Treatment of experimental pyelonephritis in the monkey 总被引:4,自引:0,他引:4
Previous studies show that chronic pyelonephritis and end stage renal disease may follow acute pyelonephritis in children and adolescents when improperly or inadequately treated. Our study shows that there is a significant decrease in renal function following untreated acute bacterial pyelonephritis due to nephron loss. The acute inflammatory response is responsible for much of the renal damage, although damage from renal ischemia is an additional significant factor. The present study used a combination of an antibiotic and a xanthine oxidase inhibitor (allopurinol) as compared to antibiotic therapy alone begun 72 hours after infection. Both were successful in eradicating the infection rapidly, but did not entirely prevent renal damage. Treatment prior to 72 hours thus is important. It appears that the combined treatment, designed to eradicate the bacteria as well as reduce the post-ischemic reperfusion damage and the phagocytic burst of phagocytosis is ideal, as this combined treatment was effective in preventing almost all renal damage and loss of renal function. 相似文献
5.
Efficacy of SIV/deltaB670 glycoprotein-enriched and glycoprotein-depleted subunit vaccines in protecting against infection and disease in rhesus monkeys 总被引:11,自引:0,他引:11
M Murphey-Corb R C Montelaro M A Miller M West L N Martin B Davison-Fairburn S Ohkawa G B Baskin J Y Zhang G B Miller 《AIDS (London, England)》1991,5(6):655-662
Immunization with an inactivated whole-virus vaccine is highly effective in preventing lentivirus infection. The viral protein(s) essential to the induction of protective responses, however, have not been identified. To define the role of virion components in the induction of protective immunity, we evaluated the efficacy of glycoprotein-enriched and glycoprotein-depleted simian immunodeficiency virus (SIV) subunit vaccines prepared by lentil-lectin affinity chromatography of gradient-purified virions using the immunization and challenge regimen previously found successful with an inactivated whole-virus vaccine. Infection was determined by successful recovery of virus, the induction of SIV-specific antibody responses, and infection of naive recipients by inoculation with lymph-node-derived lymphocytes from the vaccinates. Immunization with the glycoprotein-enriched preparation prevented infection in two out of four monkeys, whereas the glycoprotein-depleted vaccine failed to prevent infection in all four vaccinates tested. However, the glycoprotein-depleted vaccine appeared to moderate the progression of SIV-induced disease compared with non-immunized infected control monkeys inoculated with the same challenge dose. These data suggest that subunit vaccines containing sufficient quantities of viral glycoproteins can protect against SIV infection, whereas subunit vaccines composed predominantly of viral core proteins cannot. The development of effective vaccines against HIV infection should include studies on the optimum presentation of the viral envelope glycoproteins to produce long-term broadly protective immune responses. 相似文献
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Glutaurine (gamma-L-glutamyl taurine), a proposed hormone isolated from parathyroid gland oxyphil cells, was examined for its effect on circulating thyroid hormones in the rat. In acute experiments performed over a 24 hr. period, glutaurine depressed plasma triiodothyronine (T3) levels in a dose-dependent manner; however, thyroxine (T4) levels were not affected significantly. In chronic experiments performed over a 2 wk. period, glutaurine significantly increased T3 levels, but, as with acute studies, the effect of T4 levels was not significantly altered. Following acute glutaurine administration, TSH levels were elevated above control. The increased T3 observed following chronic glutaurine administration may be due to a secondary increase in TSH levels. These data support the hypothesis that glutaurine aids in peripheral thyroid hormonal regulation. Observed differences between acute and chronic glutaurine action are though to result from the effect of glutaurine on the negative feedback inhibiting action of TSH. 相似文献
9.
Background
Temporomandibular joint (TMJ) arthritis is frequently seen in children with chronic arthritis. It has rarely been described in a non-infectious acute setting. We report a case of reactive arthritis isolated to the TMJs and cervical spine. 相似文献10.
Julius Klominek Berivan Baskin Dan Hauzenberger 《Clinical & experimental metastasis》1998,16(6):529-539
Platelet-derived growth factor BB (PDGF BB) and the PDGF receptor b are expressed on mesotheliomacells, but their biological function has not yet been defined. In the present study we used Boyden chambersfitted with filters coated with the adhesive matrix proteins fibronectin, laminin, collagen type IV or the non-matrixadhesive molecule poly-L-lysine (PLL). Mesothelioma cells migrated towards PDGF BB at concen-trationsranging from 0.78 to 12.5 ng/ml if matrix proteins were present as adhesive substrates. This migrationwas integrin dependent since the same cells failed to migrate if the adhesive interactions necessary for migra-tionwere provided by molecules other than integrins. Migration of mesothelioma cells on fibronectin, lamininor collagen-type IV in response to PDGF BB was inhibited if the cells were pretreated with blocking anti-bodiesto a3b1 integrin. These findings describe for the first time PDGF BB as a chemoattractant for malig-nantmesothelioma cells and that collaboration between PDGF receptor b and integrin a3b1 is necessaryfor the motile response of these cells to PDGF BB.©Kluwer Academic Publishers 相似文献