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Two cases of orbital myositis are reported in which precise identification of the involved muscle was possible with the use of surface coil nuclear magnetic resonance (NMR) imaging. A clinical response to oral steroids in both cases coincided with a marked reduction in the abnormal thickening of the muscles as seen on the NMR images. 相似文献
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Dopamine receptors in the ventral tegmental area affect motor, but not motivational or reflexive, components of copulation in male rats 总被引:1,自引:0,他引:1
E.M. Hull M.S. Weber R.C. Eaton R. Dua V.P. Markowski L. Lumley J. Moses 《Brain research》1991,554(1-2):72-76
Microinjection of apomorphine into the ventral tegmental area (VTA) of male rats was previously shown to delay the onset of copulation and slow its rate, presumably by stimulating impulse-regulating autoreceptors on cell bodies of the A10 mesocorticolimbic dopamine tract. Such stimulation would be expected to slow the firing rate of these neurons and, thereby, to impair locomotion and/or motivational processes. The present experiments tested whether the delayed onset and slowed rate of copulation were related to deficits in motor performance, sexual motivation, and/or genital reflexes. In X-maze tests the speed of running to all 4 goal boxes was slowed; however, the percentage of trials on which the male chose the female's goal box was not decreased. Examination of videotaped copulation tests revealed that the male showed fewer complete copulatory behaviors (mounts, intromissions, and ejaculations), but more misdirected or incomplete copulatory attempts after apomorphine in the VTA. There were also fewer scores of active, as opposed to inactive, behaviors, and the onset and rate of copulation were slowed. The total number of female directed behaviors was not different in apomorphine tests, compared to vehicle. Finally, tests of ex copula genital reflexes revealed no significant effects of apomorphine in the VTA on erections, penile movements, or seminal emissions. These data suggest a role of the VTA in the motor aspects and/or sensorimotor integration of copulation. Sexual motivation and ex copula genital reflexes appeared to be unaffected by apomorphine in the VTA. 相似文献
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Mediastinal widening in an adult is mostly nodal in origin. Occasionally vascular aneurysms may be the underlying cause, in which case the aorta or its branches are most frequently involved. Thoracic venous aneurysms, on the other hand, have been reported only in anecdotes, with fusiform aneurysm of the superior vena cava being the commonest. Isolated aneurysms involving the brachiocephalic/innominate vein are extremely rare. We describe detection of a saccular aneurysm of the innominate vein, as the underlying cause of mediastinal widening seen on a chest radiograph in a 42-year-old asymptomatic woman. The characteristic radiological findings of thoracic venous aneurysms are described with particular reference to the importance of multiplanar computed tomography in such settings. Also discussed is the role of imaging in the diagnosis and guiding the management of this rare entity. 相似文献
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Hegde VA Vivas Y Shah H Haybron D Srinivasan V Dua A Gradman A 《Heart, lung & circulation》2007,16(6):423-427
BACKGROUND: Patients with the antiphospholipid syndrome (APLS) have severe involvement of the cardiovascular apparatus and often need surgical interventions to correct these manifestations. Few studies that have looked at the outcomes of cardiothoracic surgeries in APLS patients have reported high rates of perioperative mortality and thromboembolic events. OBJECTIVE: Our goal was to examine the outcomes of adult APLS patients undergoing coronary artery bypass surgery (CABG) and/or valvular surgery. We also wanted to determine whether aggressive anticoagulation therapy could prevent life threatening thromboembolic complications in these patients. METHODS: We retrospectively reviewed medical records of nine patients with primary APLS undergoing cardiothoracic surgery between 1985 and 2005 at our institution. Patient demographics, operative procedures and one-year clinical outcomes were obtained. RESULTS: Forty-five percent of our patients had more than three cardiovascular risk factors other than APLS. There were no mortalities in our case series. However, 89% of our patients developed major complications. Despite aggressive anticoagulation, 37.5% developed thromboembolic events including cerebrovascular accidents, myocardial infarctions and vena caval thrombosis. Other complications included heparin-induced thrombocytopenia, redo of CABG surgery and sepsis. CONCLUSION: Despite aggressive anticoagulation and lack of significant pre-operative co-morbidities, APLS patients undergoing cardiothoracic surgery appear to have high rates of post-operative clinical events. 相似文献
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Recent advances in computed tomography (CT) technology have made this technique useful in evaluating coronary anatomy. Although CT has been the method of choice to evaluate vascular anatomy of the thorax for many years, the coronary arteries, until recently, could not be imaged with diagnostic quality due to cardiac and respiratory motion. The improved temporal and spatial resolution of new-generation multirow detector scanners makes noninvasive evaluation of the coronary arteries possible. Magnetic resonance imaging (MRI) has been the noninvasive method of choice to evaluate proximal coronary anatomy, but is not available in many centers. CT angiography (CTA) is more readily available, has better spatial resolution than MRI, and is quickly becoming an alternate method to evaluate the coronary arteries. Cardiac catheterization is the gold standard in imaging normal and abnormal coronary arteries, but even this technique has limitations. It is occasionally difficult to delineate the course of anomalous vessels, particularly if the anomalous vessel courses between the aorta and pulmonary artery, or if it has an intramyocardial course. We describe a patient with this type of abnormal coronary anatomy in whom CTA supplemented the invasive angiogram. 相似文献