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41.
Jack Cornelius Levent Kirisci Maureen Reynolds Ralph Tarter 《The American journal of drug and alcohol abuse》2014,40(3):225-229
Background: Stress is a well-documented factor in the development of addiction. However, no longitudinal studies to date have assessed the role of stress in mediating the development of substance use disorders (SUD). Our previous results have demonstrated that a measure called Transmissible Liability Index (TLI) assessed during pre-adolescent years serves as a significant predictor of risk for substance use disorder among young adults. However, it remains unclear whether life stress mediates the relationship between TLI and SUD, or whether stress predicts SUD. Methods: We conducted a longitudinal study involving 191 male subjects to assess whether life stress mediates the relationship between TLI as assessed at age 10–12 and subsequent development of SUD at age 22, after controlling for other relevant factors. Results: Logistic regression demonstrated that the development of SUD at age 22 was associated with stress at age 19. A path analysis demonstrated that stress at age 19 significantly predicted SUD at age 22. However, stress did not mediate the relationship between the TLI assessed at age 10–12 and SUD in young adulthood. Conclusions and scientific significance: These findings confirm that stress plays a role in the development of SUD, but also shows that stress does not mediate the development of SUD. Further studies are warranted to clarify the role of stress in the etiology of SUD. 相似文献
42.
43.
Nuran Yazıcıoğlu M.D. Alev Arat Özkan M.D. Kadriye Orta Kılıçkesmez M.D. Cengiz Çeliker M.D. Murat Mert M.D. Seçkin Pehlivanoglu M.D. Rasim Enar M.D. Canan Karatay M.D. Serdar Küçükoğlu M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(7):765-769
Background: The widespread use of percutaneous mitral commissurotomy (PMC) has led to an increase in restenosis cases. The data regarding follow‐up results of repeat PMC are quite limited. The aim of this retrospective analysis is to evaluate the immediate and midterm results of the second PMC, in patients with symptomatic mitral restenosis after a succesful first procedure. Methods: Twenty patients (95% female, mean age 37 ± 4 years) who have undergone a second PMC, 6.3 ± 2.5 years after a first successful intervention built the study group. All were in sinus rhythm, with a mean Wilkins score of 8.5 ± 1.2. Results: The valve area increased from 1.2 ± 0.2 to 1.9 ± 0.2 cm2 and mean gradient decreased from 10.5 ± 3.4 to 6.1 ± 1.1 mmHg. There were no complications except for a transient embolic event without sequela (5%) and two cases (10%) of severe mitral regurgitation. The immediate success rate was 90%. The mean follow‐up was 70 ± 29 months (36–156 months). The 5‐year restenosis and intervention (repeat PMC or valve replacement) rates were 9.1 ± 5.2% and 3.6 ± 3.3%, respectively. The intervention free 5‐year survival in good functional capacity (New York Heart Association [NYHA] I–II) was 95.1 ± 5.5% and restenosis and intervention free 5‐year survival with good functional capacity was 89.7 ± 6.8%. Conclusions: Although from a limited number of selected patients, these findings indicate that repeat PMC is a safe and effective method, with follow‐up results similar to a first intervention and should be considered as the first therapeutic option in suitable patients. (Echocardiography 2010;27:765‐769) 相似文献
44.
Feske U Tarter RE Kirisci L Gao Z Reynolds M Vanyukov M 《The American journal of drug and alcohol abuse》2008,34(3):307-320
Previous research has shown that a trait termed neurobehavior disinhibition (ND) measured in childhood predicts substance use disorder by young adulthood. The present investigation extends these findings by determining the degree to which peer environment mediates the association between ND and development of cannabis use disorder (CUD). ND was measured in a sample of 216 boys 10-12 years of age. The peer environment was assessed at age 16. Current CUD was determined at age 22. Paternal and maternal SUD predicted son's ND which, in turn, predicted son's peer environment and, subsequently, son's cannabis use frequency and CUD. Peer environment mediated the association between ND and cannabis use and ND and CUD. Maternal and paternal SUD predicted the peer environment. Parental SUD, son's ND, and son's peer environment predicted CUD at age 22 with 84% accuracy. 相似文献
45.
Deli A Kreidl E Santifaller S Trotter B Seir K Berger W Schulte-Hermann R Rodgarkia-Dara C Grusch M 《World journal of gastroenterology : WJG》2008,14(11):1699-1709
In many parts of the world hepatocellular carcinoma (HCC) is among the leading causes of cancer-related mortality but the underlying molecular pathology is still insufficiently understood. There is increasing evidence that activins, which are members of the transforming growth factor β (TGFβ) superfamily of growth and differentiation factors, could play important roles in liver carcinogenesis. Activins are disulphide-linked homoor heterodimers formed from four different β subunits termed βA, βB, βC, and βE, respectively. Activin A, the dimer of two βA subunits, is critically involved in the regulation of cell growth, apoptosis, and tissue architecture in the liver, while the hepatic function of other activins is largely unexplored so far. Negative regulators of activin signals include antagonists in the extracellular space like the binding proteins follistatin and FLRG, and at the cell membrane antagonistic coreceptors like Cripto or BAMBI. Additionally, in the intracellular space inhibitory Smads can modulate and control activin activity. Accumulating data suggest that deregulation of activin signals contributes to pathologic conditions such as chronic inflammation, fibrosis and development of cancer. The current article reviews the alterations in components of the activin signaling pathway that have been observed in HCC and discusses their potential significance for liver tumorigenesis. 相似文献
46.
Fadlullah Aksoy Remzi Dogan Orhan Ozturan Selahattin Tugrul Bayram Veyseller Omer Faruk Ozer Alev Pektas 《Clinical and experimental otorhinolaryngology》2015,8(4):312-319
Objectives
In this study we investigated the probable protective effects of thymoquinone on amikacin-induced ototoxicity in rats.Methods
Thirty-two healthy rats were divided into four groups (amikacin, amikacin+thymoquinone, thymoquinone, and no treatment). Thymoquinone was fed to the rats via oral gavage in a dose of 40 mg/kg/day throughout the study period of 14 days. Amikacin was given by the intramuscular route in a dose of 600 mg/kg/day. Audiological assessment was conducted by the distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) tests, administered to all rats at the beginning of the study, and also on days 7 and 15. Biochemical parameters were calculated at the termination of the study to evaluate the oxidative status.Results
There were significant decreases in DPOAE values and significant increases in ABR thresholds of the amikacin group on days 7 and 15, as compared to the amikacin+thymoquinone group. While ABR thresholds of the amikacin group increased significantly on days 7 and 15 as compared to their initial values, there were no significant differences between the initial and the 7th and 15th day values of ABR thresholds in the amikacin+thymoquinone group. Total oxidant status and oxidative stress index values of the amikacin+thymoquinone group were significantly lower than those of the amikacin group. Total antioxidant status values of the amikacin+thymoquinone group were significantly higher than those of the amikacin group.Conclusion
Our study has demonstrated that the ototoxic effect brought forth by amikacin could be overcome with the concurrent use of thymoquinone. 相似文献47.
Successful repair of a large aortic abscess causing apical displacement of the anterior mitral valve
Anatomic continuity between the anterior mitral leaflet and the aortic root may predispose those patients with aortic root pathology to functional changes of the mitral valve without any involvement of this valve. A 34-year-old man presented with aortic valve endocarditis. Transthoracic echocardiograpy showed severe aortic regurgitation with a large aortic root abscess. The anterior leaflet of the mitral valve was displaced towards the apex of the heart causing moderate mitral regurgitation. The patient underwent aortic valve replacement with reconstruction of the aortic annulus and ventriculoaortic continuity. This procedure alone restored the mitral valve structure and function without any need for intervention on the mitral valve. Aortic abscess is a serious complication of aortic valve endocarditis and may alter the function of other structures of the heart, especially the mitral valve. Restoration of aortic wall integrity and left ventricular – aortic continuity usually restores the mitral valve structure and function if the valve is unaffected by the infection. A decision on the mitral valve should be made following correction of the aortic pathology. 相似文献
48.
Tugba Mandal Şenay Aydın Dilek Kanmaz Ahmet Levent Karasulu Gülfidan Aras Esin Tuncay 《Sleep & breathing》2016,20(3):1021-1027
Aim
Willis-Ekbom disease (RLS/WED) is common in chronic obstructive pulmonary disease (COPD). Patients with RLS/WED have poorer quality of sleep and more fatigue and depressive symptoms. The prevalence of RLS/WED in patients with COPD has been reported to vary between 29.1 and 36.8 %. However, during exacerbation, the prevalence can increase up to 54 %. These rates are higher than those seen in general population. We have not enough knowledge regarding the association between RLS and COPD. In this study, we aimed to determine the frequency of RLS in patients with stable COPD without comorbid conditions. In addition, we also aimed to determine possible related causative factors.Method
We included 80 COPD patients without comorbid conditions who presented to our outpatient clinic between April 2013 and September 2013 for RLS/WED evaluation. Three cases that have polyneuropathy and one case that refused undergoing electromyography (EMG) examination were excluded from the study. Demographic data, P-A chest X-rays, pulmonary function tests (PFT), biochemical parameters (including hemogram), and dyspnea scales were evaluated for each patient. In addition, the RLS/WED rating scale and Epworth Sleep Scale (ESS) were applied. Further, each patient diagnosed with RLS/WED underwent a detailed neurological examination (performed by a neurologist) and an EMG examination to rule out polyneuropathy.Results
Out of 76 COPD cases included in our study, 26.3 % (n?=?20) were diagnosed with RLS/WED (mean age 60.4?±?7.5 years, 20 males). The cases with RLS/WED had significantly lower body mass index (BMI) than cases without RLS/WED (p?=?0.009). There were no significant differences between cases with and without RLS/WED with respect to PFT, dyspnea scales, and arterial blood gas values. However, ESS was significantly different (p?=?0.016). There were no significant differences in RLS/WED scores and mean hs-CRP levels between COPD stages (p?=?0.424; p?=?0.518, respectively), while ESS was significantly different (p?=?0.016). ESS was significantly higher in stage B COPD than in stages A and D (p?=?0.005, p?=?0.008, respectively). Based on our model, we found that exacerbations and iron binding capacity (UIBC) were predictive factors for RLS/WED (p?<?0.100)Conclusion
RLS/WED is a common disease in cases with stable COPD. Despite our hypothesis suggesting that the prevalence of RLS/WED in COPD is related with systemic inflammation, we did not find a significant association between hs-CRP and COPD cases with RLS/WED. However, we did find that UIBC is a predictive factor for the development of RLS/WED. Nonetheless, further studies are needed to understand the relationships between UIBC, low BMI, and the development of RLS/WED in COPD.49.
Ozlen Rodop Ozgur Levent Akcay Nesrin Tutas Onur Karadag 《Saudi Journal of Ophthalmology》2015,29(3):205-209
Purpose
To evaluate the efficiency of perforated punctal plug in acquired punctal stenosis.Materials and methods
Forty-five eyes of 33 patients who had epiphora due to punctal stenosis were included in this study. After biomicroscopic examination and lacrimal dilatation punctal stenosis was managed with the perforated punctal plugs in all patients. In the following period epiphora, plug tolerance, lacrimal drainage were evaluated and graded. Lacrimal drainage was evaluated with fluorescein dye disappearing test.Results
The age of the patients ranged between 31 and 80 (mean 55.78 ± 13.11). Preoperatively punctal dilatation and lacrimal system irrigations were performed on all patients. Lacrimal system irrigation was positive in all patients. Perforated punctal plugs were placed in the inferior puncti in all patients. The plugs were explanted 6 months after operation. The follow-up period ranged between 6 and 24 months. Plug tolerance was good in 97.8% of the eyes in the 1st month visit. Epiphora decreased remarkably in 88.9% of the patients 1 month after plug implantation, except one whose plug dropped off spontaneously in 2 weeks. Fluorescein disappearing times were found under 3 min in 97.8% of the eyes after plug explanations.Conclusion
Punctum stenosis is one of the several disorders that cause lacrimal drainage obstruction. Perforated punctal plugs are found convenient and effective in managing punctal stenosis. 相似文献50.
Arat-Ozkan A Okçün B Mert M Baran T Küçükoglu S 《The Journal of heart valve disease》2004,13(4):630-631
Complications of valve replacement are diverse. In addition to morbidity due to the prosthetic valve itself (e.g. endocarditis, thrombosis), complications due to operative technique may occur in complex cases, as in aortic valve replacement with annular enlargement. Postoperative echocardiography is a simple, non-invasive method to evaluate patients with prosthetic valves. Detailed knowledge of the surgical technique employed and of probable complications is necessary to make an accurate diagnosis. The case is reported of a woman with aortic valve replacement and annular enlargement who had mitral regurgitation due to a tear in the anterior mitral leaflet as a complication of Manouguian's annulus enlargement. 相似文献