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1.
BACKGROUND: Isolated myocardial bridging (MB) often is considered to be an unimportant angiographic finding; however, its association with cardiovascular event has been shown. In this study we aimed to assess exercise-induced electrocardiographic (ECG) changes and susceptibility to arrhythmia in patients with MB. METHOD: 21 consecutive patients who had angiographically proven MB (group I) and 25 subjects (group II) who had normal coronary arteries underwent exercise test using Bruce protocol. Before and after the exercise test the changes in QT interval duration and dispersion were compared. RESULTS: Baseline characteristics of both groups were similar. Heart rate significantly increased after exercise test in both groups. In group I, after exercise mean QT(max) and QT(min) durations did not change significantly compared to baseline values, respectively. (QT(max): 411+/-20 vs. 421+/-18 ms, p>0.05 and QT(min): 380+/-12 vs. 378+/-10 ms, p>0.05). However, following exercise test QT dispersion (QT(d)) and corrected QT dispersion (QT(cd)) significantly increased when compared to baseline values, respectively. (34+/-13 vs. 66+/-14 ms, p<0.05 and 37+/-14 vs. 69+/-17 ms, p<0.05) On the other hand, in control group QT(max) and QT(min) durations, QT(c) and QT(cd) did not change significantly compared to baseline values, respectively. (QT(max): 408+/-18 vs. 412+/-17 ms, p>0.05 and QT(min): 390+/-11 vs. 387+/-10 ms, p>0.05; QT(d): 25+/-14 vs. 31+/-16 ms, p>0.05; QT(cd): 27+/-15 vs. 33+/-17 ms, p>0.05). CONCLUSION: Treadmill exercise test significantly increased QT dispersion in patients with MB. This increase may result from exercise-induced ischemia at the area perfused by bridged artery.  相似文献   
2.
A 49-year-old woman who had idiopathic thrombocytopenic purpura was admitted to our hospital with severe chest pain. Electrocardiography revealed inferolateral myocardial infarction. The patient underwent immediate coronary angiography, which revealed thrombi in the left coronary system. Percutaneous intervention was not indicated, because the thrombi had occluded the distal segments of multiple coronary arteries. Administration of tirofiban satisfactorily dissolved the thrombi.Key words: Coronary thrombosis, multivessel; myocardial infarction; platelet aggregation inhibitors/therapeutic use; purpura, thrombocytopenic, idiopathic/therapy; tirofibanIdiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder in which autoantibodies bind platelets, leading to their sequestration by the reticuloendothelial system.1 Patients with ITP typically have mucocutaneous bleeding. Although such reports are rare, thrombotic complications such as acute myocardial infarction (MI) and stroke also occur in patients with ITP.2–4 We present the case of a middle-aged woman with ITP who sustained an acute MI caused by multivessel coronary thrombosis.  相似文献   
3.
Intestinal ischemia/reperfusion (I/R) is a complex phenomenon that causes destruction of both local and remote tissues. The objective of this study was to investigate the possible participation of oxidized low-density lipoproteins (oxLDLs) and inducible nitric oxide synthase (iNOS) expression in renal tissue damage after intestinal I/R. The superior mesenteric artery was blocked for 30 minutes, followed by 24 hours of reperfusion. At the end of the reperfusion period, renal tissues were removed; the presence of oxLDL, superoxide dismutase enzyme activity, malondialdehyde levels, and iNOS expression were evaluated. I/R resulted in positive oxLDL staining in renal tissue. Compared with control rats, tissue from the I/R group showed significantly higher malondialdehyde levels and lower superoxide dismutase enzyme activity. Strong and diffuse iNOS expression was present in the I/R group. Our findings support the hypothesis that I/R of intestinal tissue results in oxidative and nitrosative stress and enhances lipid peroxidation in the end organ. These data show that oxLDL accumulates in rat renal tissue after intestinal I/R. Antioxidant strategies may provide organ protection in patients with reperfusion injury, at least by affecting interactions with free radicals, nitric oxide, and oxLDL. This study demonstrates for the first time that oxLDL may play a role in renal tissue damage after intestinal I/R. Antioxidant strategies may be beneficial for protection from reperfusion injury.  相似文献   
4.
OBJECTIVE: The purpose of this report is to present a tularemia case accompanied by a neck mass that easily may be confounded with dental abscess. SUMMARY: Francisella tularensis is a potential agent of biologic terrorism. Thirty percent of the symptoms seen in tularemia localize in the head and neck region and are sometimes mistaken for complications of a dental abscess. To our knowledge, reports of the differential diagnostic characteristics of tularemia are lacking in the dental literature and, to date, no dental journal articles have focused on the disease. In this present case, a 51-year-old woman arrived at the public health department with high fever and facial swelling. The findings suggested a dental origin and the patient was directed to dentistry. Radiology and a detailed intraoral and extraoral examination failed to reveal a dental problem. Fortunately, the patient was known to come from a tularemia region; with the suspicion of tularemia the patient was referred to the faculty of medicine. Serologic tests showed that the patient had a Francisella tularensis infection.  相似文献   
5.
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative 12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects with bioactive glass compared to the treatment with bioabsorbable membrane.  相似文献   
6.
Nine cases of posterior fossa chordomas are presented. The clinical features, treatment, and outcomes are discussed. Two patients underwent transoral surgery. Advantages and disadvantages of this approach are discussed and related to the recent literature.  相似文献   
7.
OBJECTIVES: Macrolide-lincosamide-streptogramin B (MLSB) resistance determinants of group A streptococci (GAS) in Ankara, Turkey, were defined for the first time. ISOLATES AND METHODS: A total of 1355 GAS isolates, collected from three different regions of Ankara, were screened for erythromycin resistance. Resistance phenotypes were determined by a triple-disc test, and the gene determinants responsible were determined by PCR. MICs of erythromycin, clindamycin and spiramycin were measured for the resistant isolates, and susceptibility rates to some further antibiotics were determined. RESULTS: Thirty-six isolates (2.6%) were resistant to erythromycin. Of these, 17 (47.2%) expressed macrolide-restricted resistance (M phenotype), while the remainder expressed inducible (16 isolates, 44.4%) or constitutive (three isolates, 8.3%) MLSB resistance. All isolates of the M phenotype harboured the mef(A) gene. Of non-M isolates, 14 harboured erm(A) subclass erm(TR) and five had erm(B) genes. There was a significant relationship between tetracycline resistance and the inducible phenotype (P < 0.05). Macrolide resistance was significantly higher in adults (P < 0.05), and increased more than two-fold in 2002 compared with 2001 (P < 0.05). CONCLUSION: The prevalence of macrolide resistance in GAS is low in Ankara; therefore, routine antimicrobial susceptibility testing against these agents seems unwarranted.  相似文献   
8.
AIM: TO investigate the effect of exogenous erythro- poietin (EPO) administration on acute lung injury (ALI) in an experimental model of sodium taurodeoxycholate- induced acute necrotizing pancreatitis (ANP). METHODS: Forty-seven male Wistar albino rats were randomly divided into 7 groups: sham group (n = 5), 3 ANP groups (n = 7 each) and 3 EPO groups (n = 7 each). ANP was induced by retrograde infusion of 5% sodium taurodeoxycholate into the common bile duct. Rats in EPO groups received 1000 U/kg intramuscular EPO immediately after induction of ANP. Rats in ANP groups were given 1 mL normal saline instead. All animals were sacrificed at postoperative 24 h, 48 h and 72 h. Serum arnilase, IL-2, IL-6 and lung tissue malondialdehyde (MDA) were measured. Pleural effusion volume and lung/body weight (LW/BW) ratios were calculated. Tissue levels of TNF-a, IL-2 and IL-6 were screened immunohistochemically. Additionally, ox-LDL accumulation was assessed with immune-fluorescent staining. Histopathological alterations in the lungs were also scored.RESULTS: The mean pleural effusion volume, calculated LW/BW ratio, serum IL-6 and lung tissue MDA levels were significantly lower in EPO groups than in ANP groups. No statistically significant difference was observed in either serum or tissue values of IL-2 among the groups. The level of tumor necrosis factor-(~ (TNF-(~) and IL-6 and accumulation of ox-LDL were evident in the lung tissues of ANP groups when compared to EPO groups, particularly at 72 h. Histopathological evaluation confirmed the improvement in lung injury parameters a~er exogenous EPO administration, particularly at 48 h and 72 h. CONCLUSION: EPO administration leads to a significant decrease in ALI parameters by inhibiting polymorphonuclear leukocyte (PMNL) accumulation, decreasing the levels of proinflammatory cytokines in circulation, preserving microvascular endothelial cell integrity and reducing oxidative stress-associated lipid peroxidation and therefore  相似文献   
9.
10.
In this study we aimed to evaluate the in vivo effects of myrtle oil (myrtii oleum) on the antioxidant enzymes such as superoxide dismutase and catalase, the levels of malondialdehyde in liver tissues as an index of lipid peroxidation and nitrite–nitrate levels in normoglycaemic and alloxan-induced diabetic and MO-treated rabbits. In our previous study, we assumed that MO with a dose of 50 mg/kg, possesses a hypoglycemic activity and this activity was independent from the effects of insulin. Myrtle oil exerts its hypoglycemic activity by enhanced glycolysis, glycogenesis and decreased glycogenolysis. What is more glucose load data strongly suggest that MO treatment produces hypoglycemia mainly by reducing intestinal absorption of glucose, so MO could be an -glycosidase enzyme inhibitor which had a hypoglycaemic effect only on alloxan-induced diabetic rabbits on the fourth hour and on orally glucose loaded group. The major finding of this new study is that, MO may not offer any protection against oxidative stress during acute studies in normoglycemic and diabetic groups. Although the levels of superoxide dismutase and catalase enzyme activities did not change during acute studies in diabetes + MO group, there was a significant change at the end of 21 days. There is a very limited knowledge about MO and its effects on diabetes. Therefore, we tried to explain the mechanism that might underlie the protective effects of MO with this paper.  相似文献   
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