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991.
Emine Yilmaz Sipahi Ishak Ozel Tekin Mustafa Comert Figen Barut Huseyin Ustun Tunc Hakan Sipahi 《Pharmacological research》2004,50(6):585-591
Oxidation of the low-density lipoprotein (LDL) results in the production of modified LDLs. Oxidation of LDL cholesterol plays a role on the pathogenesis of endothelial dysfunction. This study was designed to investigate the possible participation of the oxidative modification of low density lipoprotein in the lung edema induced by alpha-naphthylthiourea (ANTU), which is a well-known noxious chemical agent on the lung endothelium. When ANTU injected intraperitoneally into rats (15 mg kg(-1)), it produced lung edema as indicated by an increase in lung weight/body weight (LW/BW) ratio and pleural effusion (PE) reaching a maximum within 4 h. A significant lung edema was observed 4 h after intraperitoneally injection of alpha-naphthylthiourea when compared with olive oil-injected control rats. On microscopic examination of alpha-naphthylthiourea-treated rats were shown to have severe lung injury, while no change was observed in olive oil-treated control rats. While there were no staining in control lungs, positive oxidized low-density lipoproteins immune-fluorescent staining were observed in lung edema group. Our study showed that oxidized low-density lipoprotein (oxLDL) accumulated in ANTU-induced lung damage. This is the first study in which accumulation of oxLDL molecules in the intact lung tissue were shown by fluorescent immune-staining method in experimental lung edema. The potential role of oxLDL in this pathology are still under investigation. 相似文献
992.
993.
(Received for publication on Dec. 8, 1998; accepted on Sept. 17, 1999) 相似文献
994.
Research has shown a relationship between community violence exposure and heightened aggression in young adults (Scarpa, in press). This study tests the role of psychophysiological functioning in mediating this relationship. Fifty-four university students (mean age = 20.25) were selected from a screening sample (N= 476) based upon high- and low-violence exposure. Salivary cortisol, heart rate (HR), and heart rate variability (HRV) were obtained before and after two stressor tasks. Aggression was reported before the tasks. Aggression was significantly correlated with reduced baseline HR, increased baseline HRV, and increased poststressor cortisol. However, exposed groups did not differ psychophysiologically, suggesting that psychophysiological functioning does not serve as a mediator. Instead, violence exposure and psychophysiological functioning have independenteffects on aggressive behavior. © 2000 John Wiley & Sons, Inc. 相似文献
995.
Background and objectivesMost studies to date have focused on the negative aspects of anxiety. Anxiety, however, is an evolved emotional response that can provide protection in the face of risk. Pandemics are characterized by increased mortality risk coupled with future uncertainties, which both cause heightened anxiety. Here, we examine the factors associated with anxiety levels and risk avoidance behaviours during the first wave of the COVID-19 pandemic. We asked how individual time perspectives (future-oriented consideration and attention to present moment experience) affect anxiety in uncertain times, and whether anxiety reduces mortality risk by promoting risk avoidance behaviour.MethodologyWe conducted an online survey in the UK (N = 1088) and Turkey (N = 3935) and measured participants’ generalized and pandemic-related anxiety levels, future-oriented consideration, mindfulness, intolerance of uncertainty, risk perception and risk avoidance behaviours.ResultsWe found that people less tolerant of uncertainties had higher levels of pandemic anxiety. Those with higher pandemic anxiety exhibited risk avoidance behaviours more frequently. Mindfulness and increased financial satisfaction reduced pandemic anxiety. People in Turkey reported higher levels of generalized and pandemic anxiety and greater engagement in risk avoidance behaviours than people in the UK.Conclusions and implicationsOur study shows an elevated anxiety response can help mitigate infection risk during pandemics and emphasizes the importance of the underlying situation in understanding whether an anxiety response is adaptive or pathological. Maintaining a healthy level of anxiety can promote engagement in protective behaviours. Therapies addressing anxiety can focus on increasing tolerance to future uncertainties.Lay summaryAnxiety is an emotional response triggered in the anticipation of a possible threat. We found that intolerance of uncertainty strongly predicted anxiety and that people with elevated anxiety levels engaged in protective behaviours more frequently during the COVID-19 pandemic, suggesting that anxiety can help mitigate mortality risk. 相似文献
996.
997.
rfan Kara Sedat al Alperen Vural mdat Yüce Mete Gündo Kemal Deniz Kerem Kkolu 《Clinical otolaryngology》2019,44(3):349-355
Objectives: To investigate the relationship between the cell percentage of T regulator (Treg) cells of patients’ specimens and disease severity, survivability, recurrence and metastasis in patients who were diagnosed with nasopharyngeal carcinoma (NPC). Design, Setting and Participants: Sixty patients who were diagnosed as NPC and treated by the same protocol were enrolled to the study. Patient files were reviewed retrospectively and their clinical and pathological results were recorded. Deparaffinized samples of nasopharyngeal carcinoma patients were stained immunohistochemically with anti‐FoxP3 monoclonal antibody. All patients’s Anti‐FoxP3 stained slides were evaluated by the same pathologist. Stained Treg lymphocytes around the tumoral foci were investigated. Patients were divided into two groups according to the total anti‐FoxP3‐stained Treg cell counts of the specimens; that is, less than 20% of the total or more than 20% of the total. These groups were compared statistically. Main Outcome Measures: Intensity of FoxP3 which is related to negative tumor response was the main outcome measure. It was evaluated in terms of stage, survival, recurrence and metastasis. Results: The study group consisted of 42 male patients (70%) and 18 female patients (30%). The mean age was 47 ± 14.9. NPC subtypes among the patients were undifferentiated non‐keratinized type in 54 patients (90%), differentiated non‐keratinized type in 4 patients (6.66%) and keratinized type squamous cell carcinoma (SCC) in 2 patients (3.33%). When the two groups were compared in terms of pathological subtype, there was no significant variation between the two groups. There was also no significant variation between the two groups when compared on the basis of tumor stage (P = 0.36 for T phase, P = 0.122 for N phase), early stage, late phase (P = 0.15), survival rate (P = 0.69 for general survival), recurrence (P = 0.2 for local recurrence, P = 0.37 for regional recurrence) and distant metastasis (P = 0.3). Conclusion: There was no significant relationship between the concentration of these cells in the stained specimens and the disease stage, survival rate, recurrence and distant metastasis discovered. 相似文献
998.
Echocardiographic and morphologic examination of left ventricular false tendons in human and animal hearts 总被引:4,自引:0,他引:4
Kervancioğlu M Ozbağ D Kervancioğlu P Hatipoğlu ES Kilinç M Yilmaz F Deniz M 《Clinical anatomy (New York, N.Y.)》2003,16(5):389-395
False tendons are thin, fibrous or fibromuscular structures that traverse the cavity of the left ventricle with no connection to the valvular cusps; they may be single or multiple. We retrospectively analyzed echocardiograms for the prevalence of false tendons in the hearts of 368 (231 male, 137 female) newborns, infants, and children (mean age = 6.28 +/- 4.32 years) who were referred for echocardiography because of suspected acquired or congenital heart disease, but in whom no cardiac pathology was found. In addition, we studied the prevalence of false tendons in 90 hearts from three species of animals (dog, sheep, goat) and eight cadaveric human hearts. In our echocardiographic study, false tendons were detected in 97 of 368 hearts (26.4%). In our gross morphologic studies, false tendons were observed in most of the animal and human hearts: they were present in 5 of 8 (62.5%) human hearts, 14 of 20 (70%) dog hearts, 41 of 50 (82%) sheep hearts, and 16 of 20 (80%) goat hearts. The overall prevalence in animal hearts was 71 of 90 (78.8%). Histologic examination showed the false tendons to be composed of cardiac muscle, blood vessels, fibrous tissue, and Purkinje cells. The possible role of false tendons in innocent murmurs, cardiac rhythm disorders, or left ventricular dysfunction is discussed. 相似文献
999.
Kunt AS Darcin OT Aydin S Demir D Selli C Andac MH 《Journal of thrombosis and thrombolysis》2005,19(3):197-200
Objectives: Low-dose aprotinin in the pump during cardiopulmonary bypass (CPB) has been shown to improve postoperative hemostasis and platelet preservation. This investigation was undertaken to evaluate the effects of mini-dose pump prime only aprotinin (70 mg) on the hemostatic parameters and blood transfusion requirements in patients undergoing on-pump coronary artery bypass surgery (CABG).Materials and Methods: We studied 86 patients who underwent CABG. Forty patients received mini-dose aprotinin (500.000 KIU [70 mg] in the pump), and a control group of 46 did not. D-dimer level, full blood count, postoperative blood loss, and transfusion requirements were analyzed before, after one hour operation and first day after operation.Results: Twenty-four-hour postoperative blood loss was significantly reduced in the aprotinin group (188± 51.5 ml vs. 818± 243.5 ml, [mean ± standard deviation] p < 0.01). Patients in the aprotinin group also received significantly less banked blood posoperatively than the control group (1.20 ± 0.52 vs. 3.33 ± 1.13 Units/per patient (p < 0.04). One hour after operation, and 24 hours after operation D-dimer level was significantly reduced in the aprotinin group (p < 0.008 and p < 0.017, respectively).Conclusions: Mini dose pump-prime aprotinin reduces postoperative blood loss, transfusion requirements and yet confers hemostatic improvement through reduced fibrinolysis in patients undergoing routine coronary artery bypass grafting. 相似文献
1000.
Serkan Simsek Kazim Yigitkanli Ayhan Comert Halil I Acar Hakan Seckin Uygur Er Deniz Belen Ibrahim Tekdemir Alaittin Elhan 《Journal of clinical neuroscience》2008,15(6):686-688
The sulcus of the vertebral artery is located behind the lateral mass of the atlas and in some cases is converted into a foramen by anomalous ossification known as the posterior ponticulus (osseous bridge). This study involved anatomical observations of 158 isolated anatomical specimens of dry C1 vertebrae. The incidence and types of posterior osseous bridging were identified for the 158 dry samples of atlas vertebrae. In nine (5.6%) dry C1 vertebrae, partial osseous bridging was detected (bilaterally in eight vertebrae and unilaterally on the left in one). Complete osseous bridging (arcuate foramen) was observed in six (3.8%) dry C1 vertebrae (bilaterally in one vertebra, unilaterally on the left in three, and on the right in two). Awareness of the types of posterior osseous bridging of C1 in craniocervical junction surgery is essential, and may be helpful in surgical interventions in this region. 相似文献