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排序方式: 共有1571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.
Alp İ. Göçer M. D. Erdal Çetinalp Metin Tuna Faruk İldan Hüseyin Bağdatoğlu Sebabattin Haciyakupoğlu 《Neurosurgical review》1997,20(2):114-116
The results of percutaneous radiofrequency rhizotomy of lumbar spinal facets in 46 patients followed at least three months (mean 15 months) are reported and compared with those reported previously. Satisfactory pain relief three months after the procedure was achieved in 36.4 percent of patients without operations and in 41.7 percent of patients with operations other than fusion.No patient had previously undergone fusion.Treatment of low-back pain by using radio-frequency thermocoagulation of spinal facets is a simple, safe, and well-tolerated procedure. It can be used to relief of pain in spite of decreasing rates of success within the follow-up period. 相似文献
3.
Kemal Gündüz Nazmİ Zengİn Süleyman Okudan Mehmet Okka Nİlgün Özbayrak 《Documenta ophthalmologica. Advances in ophthalmology》1995,91(2):155-164
We recorded pattern electroretinograms and visual evoked potentials in a group of selected patients with unilateral uncomplicated branch retinal vein occlusion. To document the effects of preexisting risk factors, patients were divided into three groups: diabetes mellitus, hypertension with hyperlipidemia and no systemic disease. The transient and steady-state pattern electroretinogram and visual evoked potential amplitudes were significantly reduced and visual evoked potential peak times were delayed relative to the fellow eyes and agematched normal subjects. There was a second amplitude reduction relative to the other patient groups in both the affected and fellow eyes of the diabetes mellitus group, which was indicative of an additive effect of diabetes mellitus.Abbreviations BRVO
branch retinal vein occlusion 相似文献
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Helvacı Özant Korucu Berfu Gonul Ipek İsik Arınsoy Turgay Guz Galip Derici Ulver 《International urology and nephrology》2021,53(1):105-109
International Urology and Nephrology - The number of kidney biopsies (KB) performed in elderly patients has been increasing. Safety and usefulness of elderly KB have been well established, whereas... 相似文献
6.
Asiye İzem Sandal Hatice Şenlikci Merve Yılmazer Burcu Kartal Bedia Palabıyık Özen Banu Özdaş 《Andrologia》2021,53(5):e14032
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane. 相似文献
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9.
Internal biliary fistulas (IBF) are seen rarely. Because the symptoms and signs of IBF are not specific and the diagnosis
is not suspected, these patients are commonly investigated with plain abdominal films (PAF), ultrasonography (US), upper gastrointestinal
series (UGIS), barium enema (BE), and computed tomography (CT), but not always with endoscopic retrograde cholangiopancreatography
(ERCP). The purposes of this article are (a) to attract attention of radiologists to presumptive findings of IBF, so as not
to misdiagnose this unsuspected and rare disease, and (b) review of the literature while presenting radiologic features of
our cases. Five cases of IBFs in which extrahepatic biliary tree communicating with duodenum (four cases) and colon (one case)
are reported. Diagnostic work-up of cases were done by PAF, US, UGIS, BE, and CT. Aerobilia, which cannot be explained using
other means, ectopic gallstone and small bowel dilatation, nonvisualization of the gallbladder despite no history of cholecystectomy,
and thick-walled shrunken gallbladder adherent to neighboring organs were suggestive findings of IBF in our study. Knowledge
of imaging findings suggestive of IBF and a high index of suspicion increase the diagnostic rate of IBFs.
Received: 4 June 1998; Revision received: 28 July 1998; Accepted: 14 October 1998 相似文献
10.
Berkman MZ Iplikçioğlu AC Berkman MK Erbengi T San T Sav A 《Acta neurochirurgica》2000,142(9):1047-1054
Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients
with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and
initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine
(Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting
muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors
in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of
Tizanidine on vasospasm was evaluated.
Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid
hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration)
(n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after
the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was
prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.
Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric
analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine
administration group and control group.
Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic
insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm
needs further studies including the employment of clinically more relevant SAH models. 相似文献