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991.

Aim

We aimed to report the clinical features related to torsades de pointes (TdP) in patients with complete AV block (CAVB).

Methods

Patients with CAVB who were admitted to our instituition between January 2007 and January 2010 were retrospectively evaluated in terms of the occurence of TdP. The clinical features were compared in patients with and without TdP using the software of SPSS.

Results

Sixty-four patients were determined to have CAVB. Three of them had documented episodes of TdP. All three patients experiencing TdP were females, whereas 48% of the patients with CAVB were females. The mean age of patients with TdP was significantly greater than the mean age of the other patients (85 ±3 vs. 78±7.6, respectively; p<0.05). In our archives, bradycardia exposure time could be determined in only 49 patients without TdP. Among them, just 10 patients had been exposed to bradycardia over 48 hours, whereas all of the 3 patients with TdP had been exposed to bradycardia over 48 hours (p<0.05). Additionally, in two patients with TdP, we demonstrated that QT and QTc prolongation increases as the duration of bradycardia is extended. Furthermore, all patients with TdP had notched T waves in the ECG on the occurrence day of TdP, whereas they did not have any notched T wave in their ECG on the admission day.

Conclusion

Among the patients with CAVB, elderly females are more susceptible to development of TdP. Delay in institution of physiological heart rate leads to further QT prolongation and thereby to TdP. Besides QT prolongation, the finding of T wave notching on ECG may also have a predictive value for TdP.  相似文献   
992.
Laparoscopic surgery techniques have been increasingly preferred to classic laparotomy by surgeons since 1987. However, this method may have some side effects on different intraabdominal organs including kidneys. The aim of this study is to evaluate the effects of different pressures of CO2 on p53 related apoptosis in kidneys. Totally 24 male rats were divided into four equal groups. CO2 is insufflated into rats’ intraabdominal cavity in two different pressures of 10 and 20 mmHg during 1 h. However, in sham group, only cannula was inserted, but no gas was insufflated. After 1 h, 30 min reperfusion was applied. At last, the kidneys were excised and p53 expression and apoptosis were evaluated immunohistochemically. All the data revealed that the number of apoptotic cell in kidney’ tubular cells significantly increases in proportion to CO2 pressure level. On the other hand, p53 expression was detected only in the highest pressure. Because the low CO2 pressured group’ rats had no p53 expression in kidneys, we suggest that this method can be safely used for abdominal surgery. At the same time, increasing in the number of apoptotic cells parallel to pressure also suggest that CO2 pressure level and application time are very important parameters during CO2 pneumoperitoneum.  相似文献   
993.
The aim of this study was to determine the presence and prevalence of larval stages of Dicrocoelium dendriticum and Brachylaima sp. in the first intermediate host, a species of land snail, Helix aspersa, in Turkey. A total of 211 snails were collected in April-May 2014 from pastures in Mersin District. Larval stages of D. dendriticum were identified under a light microscope. Hepatopancreas from naturally infected H. aspersa snails were examined histologically. The prevalence of larval stages of D. dendriticum and Brachylaima sp. in H. aspersa snails was found to be 2.4% and 1.9%, respectively, in Mersin, Turkey. Cercariae were not matured in sporocysts at the beginning of April; however, it was observed that cercariae matured and started to leave sporocysts by early-May. Thus, it was concluded that H. aspersa acts as an intermediate host to D. dendriticumin and Brachylaima sp. in Mersin, Turkey. A digenean trematode Brachylaima sp. was seen for the first time in Turkey.  相似文献   
994.
Left ventricular (LV) pseudoaneurysm is a rare complication of myocardial infarction. It may also occur as a complication of mitral valve surgery, chest trauma, and bacterial endocarditis. It forms when a cardiac rupture contains adherent pericardium or scar tissue and is typically located on the posterior or inferior LV wall. Pseudoaneurysms have a propensity to spontaneous rupture; hence, immediate surgical intervention is the treatment of choice for LV pseudoaneurysms diagnosed in the first months after myocardial infarction. The management of chronic LV pseudoaneurysms is still a subject of debate.  相似文献   
995.
West Nile virus (WNV), a mosquito-borne flavivirus with significant impact on human and animal health, has recently demonstrated an expanded zone of activity globally. The aim of this study is to investigate the frequency and distribution of WNV infections in potential vectors and several mammal and avian species in Turkey, where previous data indicate viral circulation. The study was conducted in 15 provinces across Turkey during 2011–2013. In addition, the entomological study was extended to 4 districts of the Turkish Republic of Northern Cyprus. WNV exposure was determined in humans, horses, sheep and ducks from Mersin, Sanliurfa, Van and Kars provinces of Turkey, via the detection of neutralizing antibodies. WNV RNA was sought in human and equine samples from Mersin, Adana and Mugla provinces. Field-collected mosquitoes from 92 sites at 46 locations were characterized morphologically and evaluated for viral RNA. Neutralizing antibodies were identified in 10.5% of the 1180 samples studied and detected in all species evaluated. Viral nucleic acids were observed in 5.9% of 522 samples but only in horses. A total of 2642 mosquito specimens belonging to 15 species were captured, where Ochlerotatus caspius (52.4%), Culex pipiens sensu lato (24.2%) comprise the most frequent species. WNV RNA was detected in 4 mosquito pools (1.9%), that comprise Oc. caspius Cx. pipiens s.l. and DNA barcoding revealed the presence of Cx. quinquefasciatus and Cx. perexiguus mosquitoes in infected Culex pools. All WNV partial sequences were characterized as lineage 1 clade 1a. These findings indicate a widespread WNV activity in Turkey, in Eastern Thrace and Mediterranean-Aegean regions as well as Southeastern and Northeastern Anatolia.  相似文献   
996.
This experiment was designed to investigate the lipid peroxidation and histological effects of chronic fluorosis on first- and second-generation rat kidney tissues. Sixteen virgin female Wistar rats were mated with eight males (2∶1) for approx 12 h to obtain first-generation rats. Mating was confirmed by the presence of sperm in vaginal smears. Sperm in vaginal smears was observed in 10 of 16 rats (d 0). These rats were identified as pregnant and included in this experiment. Pregnant rats were divided into two experimental groups (control and fluoride-supplemented), each containing five rats. The pregnant rats in the fluoride-supplemented group were exposed to 30 mg/L sodium fluoride (NaF) in commercial drinking water containing 0.07 mg/L NaF throughout the gestation and the lactation periods. After the lactation period, young animals (first generation [F1]) were exposed to the same amount of NaF in drinking water for 4 mo. At the end of the 4-mo experimental period, nine randomly chosen male rats (F1) were sacrificed, and the kidneys were removed for the histological and lipid peroxidation examinations. The remaining eight female rats were mated with four males (2∶1) for approx 12 h to obtain second-generation rats. Six female were identified as pregnant, and treated similarly throughout the gestation and the lactation periods. After the lactation period, the young male rats (second-generation male rats [F2]) were also treated similarly for 4 mo. At the end of the 4-mo experimental period, nine randomly chosen male rats (F2) were sacrificed, and the kidneys were removed for the histological and lipid peroxidation examinations. The rats in the control groups underwent the same procedure without NaF supplementation. It was found that the plasma fluoride and kidney TBARS levels of fluoride-supplemented F1 and F2 rats were higher than controls. Hydropic epithelial cell degenerations and moderate tubular dilatation were observed in some proximal and distal tubules. There were markedly focal mononuclear cell infiltrations and hemorrhage at some areas of the interstitium, especially at the corticomedullar junction. Mononuclear cell infiltrations were also evident in some peritubular and perivascular areas. Most of the vascular structures were congestive. Many Bowman capsules were narrowed. The severe degenerative changes in most of the shrunken glomerules and vascular congestion were also observed. It is concluded that chronic fluorosis causes a marked destruction in kidney tissues of F1 and F2 rats by causing lipid peroxidation. Department of Orthopedics, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey  相似文献   
997.
Hyperinsulinism of infancy is a major cause of persistent hypoglycaemia in the newborn period. Transient mild self-limiting hyperinsulinaemia and hypoglycaemia have been described in neonates born to mothers taking ritodrine therapy for premature labour. Ritodrine crosses the placental barrier and enters the fetal circulation readily but the mechanism of how it causes hyperinsulinaemia and hypoglycaemia is unclear. We report the case of severe prolonged hyperinsulinaemic hypoglycamia in a neonate born to a mother taking ritodrine therapy from 16 weeks' gestation for preterm labour. The hyperinsulinaemic hypoglycaemia was managed with oral nifedipine as diazoxide was contraindicated due to fluid overload. Possible mechanisms of ritodrine-induced hypoglycaemia and insulin secretion are discussed.  相似文献   
998.
Three stations selected for altitude and habitat types within the Kasnak Oak Forest Nature Reserve (Isparta, Turkey) were studied comparatively for species composition, richness and abundance of the Hymenoptera families Ampulicidae, Crabronidae, and Sphecidae. A total of 56 species was recorded, 1 from the family Ampulicidae, 43 from the family Crabronidae and 12 from the family Sphecidae. 8 species are new records for Turkey.  相似文献   
999.
Archives of Microbiology - Bacterial biofilms are related to various dental and periodontal infectious diseases, and the characterization of this biological structure with micro-computed tomography...  相似文献   
1000.
Despite a vast amount of different methods, protocols and cryoprotective agents (CPA), stem cells are often frozen using standard protocols that have been optimized for use with cell lines, rather than with stem cells. Relatively few comparative studies have been performed to assess the effects of cryopreservation methods on these stem cells. Dimethyl sulfoxide (DMSO) has been a key agent for the development of cryobiology and has been used universally for cryopreservation. However, the use of DMSO has been associated with in vitro and in vivo toxicity and has been shown to affect many cellular processes due to changes in DNA methylation and dysregulation of gene expression. Despite studies showing that DMSO may affect cell characteristics, DMSO remains the CPA of choice, both in a research setting and in the clinics. However, numerous alternatives to DMSO have been shown to hold promise for use as a CPA and include albumin, trehalose, sucrose, ethylene glycol, polyethylene glycol and many more. Here, we will discuss the use, advantages and disadvantages of these CPAs for cryopreservation of different types of stem cells, including hematopoietic stem cells, mesenchymal stromal/stem cells and induced pluripotent stem cells.  相似文献   
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