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Heavy use of alcohol can lead to addictive behaviors and to eventual alcohol‐related tissue damage. While increased consumption of alcohol has been attributed to various factors including level of alcohol exposure and environmental factors such as stress, data from behavioral scientists and physiological researchers are revealing roles for the circadian rhythm in mediating the development of behaviors associated with alcohol use disorder as well as the tissue damage that drives physiological disease. In this work, we compile recent work on the complex mutually influential relationship that exists between the core circadian rhythm and the pharmacodynamics of alcohol. As we do so, we highlight implications of the relationship between alcohol and common circadian mechanisms of effected organs on alcohol consumption, metabolism, toxicity, and pathology.  相似文献   
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Several studies have related pathological gambling in PD to dopamine agonist therapy. A mail-in survey was sent to PD patients seen at the University of Florida Movement Disorders Center to determine gambling frequency and behavior, and any lifestyle or environmental factors associated with compulsive gambling in PD. 462 surveys were sent and 127 completed surveys were returned, of which ten were from patients who met criteria for compulsive gambling. All ten were taking dopamine agonists coincident with the compulsive gambling. Compulsive gamblers were younger, and psychological distress measures revealed that compulsive gamblers exhibited higher levels of anxiety, anger, and confusion. Thus in this cohort, we have uncovered the several characteristics of the most likely PD compulsive gambler, namely: (young) age, “angry”, “anxious”, and using a (dopamine) agonist.  相似文献   
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Background: Triiodothyronine regulates cardiac contractility; however, the mechanisms by which it produces its acute contractile effects remains unknown. We compared the acute effects of thyroid hormones (triiodothyronine [T3] and thyroxine [T4]) and of isoproterenol on the contractility of isolated rat hearts. In addition, we sought to determine whether the acute inotropic effects of thyroid hormones were mediated by beta-adrenergic receptors or by increased production of cyclic-3',5'-adenosine monophosphate (cAMP).

Methods: A Langendorff heart preparation harvested from euthyroid male Sprague-Dawley rats was used. Drugs were administered through an aortic perfusion catheter. A pressure-transduced left-ventricular balloon catheter measured pressure and heart rate changes. Changes in the maximum positive rate of change in pressure (dP/dT) and maximum negative dP/dT were determined. Responses to varying doses of T3, T sub 4, and isoproterenol were assessed in the presence and absence of beta-adrenergic receptor blockade with propranolol, cAMP production, measured by radioimmunoassay, was determined in myocardial cell suspensions after incubation with T3 or isoproterenol.

Results: T3 0.74 nmol rapidly and significantly increased maximum dP/dT by 335 plus/minus 38 mmHg/s within 30 s after bolus injection; however, contractility was unchanged after as much as 12.9 nmol T4. The maximal increase in dP/dT after 0.8 nmol isoproterenol was comparable to that produced by T3. However, the cardiotonic actions of isoproterenol were significantly slower to develop (peaking at 60 vs. 15 s) and lasted longer than those of T3. Pretreatment with propranolol 1 micro mol diminished the contractile effects of isoproterenol but had no effect on those of T3. Concentrations of isoproterenol that increase contractility also significantly increased cAMP production in isolated rat myocardial cells. However, T3 failed to increase cAMP production.  相似文献   

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The protective properties of nonwoven materials (Spandbond, SMS) used to manufacture 3-5-layer medical masks, by using model physical and bacterial test aerosols, were experimentally assessed. It was shown that the more layers of the materials, the less permeable they became for test aerosols. Three-five-layer masks made from SMS at a density of 42 g/m2 were found to have higher protective properties for oil mist and fine aerosol than those made from Spandbond at a density of 25 g/m2. Five-layer SMS materials at a density of 42 g/m2 have the highest values of bacterial aerosol retention.  相似文献   
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Disclosure of aneurysm of abdominal aorta indicates severity and prevalence of atherosclerotic process which means high probability of combined occlusive affections in other arterial circulations. Authors treated the patient with aneurysm of iliac artery with widespread atherosclerosis of aorta taking into account the abovementioned facts. Right stage surgical tactics assured success.  相似文献   
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