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Among the techniques for dealing with common bile stones, choledochoduodenostomy (CDS) represents a useful alternative. This operation is indicated mainly in patients with recurrent stones, giant stones, or concomitant common bile stricture and duct stones. At the present time most of the patients undergoing CDS have been already undergone endoscopic retrograde cholangiography or ultrasonography to study the common bile duct and the cause of symptoms. The common bile duct diameter is of paramount importance when determining the feasibility of performing a CDS, the critical size being 1.2 cm. The most common operation is a side-to-side anastomosis employing absorbable sutures. Stomal patency is the most important factor for preventing classic complications such as cholangitis and sump syndrome. These complications are rare, being observed in only 5% of the patients. Long-term results of the operation show that it is a safe procedure that should be considered a good option in selected patients with choledocholithiasis. 相似文献
493.
VK Yeragani R Pohl K Srinivasan R Balon C Ramesh R Berchou 《Canadian Metallurgical Quarterly》1995,56(3):289-293
Some evidence suggests that patients with panic disorder have a decreased cardiac vagal and a relatively higher sympathetic activity. In this study, spectral analysis of the time series of heart rate before and after isoproterenol infusions was used to study heart rate variability in six panic disorder patients and 11 normal control subjects. These preliminary data reveal a significant increase of sympathovagal ratios only in the patient group after isoproterenol administration. The findings suggest a relative increase in cardiac sympathetic and a relative decrease in cardiac vagal function in patients with panic disorder during isoproterenol infusions. 相似文献
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Various factors have been implicated in the pathogenesis of essential hypertension, although the exact cause of essential hypertension is still unknown. In this paper it is suggested that the basic pathology in essential hypertension may be an inherited defect in the blood supply of that part of reticular formation of rostral ventrolateral medulla which contains the pressor area. The posited defect is one in which the arterial branch supplying blood to the above-mentioned pressor area of vasomotor center arises from an artery which is stenosed. The other branches of this stenosed artery supply adjacent areas of medullary reticular formation concerned with other neurological functions. Due to this stenosis there is ischaemia of the pressor area resulting in increased systemic arterial pressure. During stress, the blood requirement of adjacent areas of the reticular formation (whose function is still not clearly defined) may increase, thus further decreasing blood flow to vasopressor area and increasing the cerebral ischaemic response. After a prolonged time, this increased blood pressure can cause hyaline arteriolar nephrosclerosis in kidney, which may participate in the maintenance of elevated systemic arterial pressure. 相似文献
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SS Kanwar V Singh VK Vinayak AK Malik SK Mehta S Mehta 《Canadian Metallurgical Quarterly》1994,38(5):269-276
We are presenting the state of knowledge concerning intraoperative light-induced retinal injury, considered to be a combination of photic retinopathy and retinal photocoagulation. It may arise from retinal light exposure to the operating microscope or to the fiberoptic endoilluminator. Ultraviolet and short-wavelength visible light are more dangerous than longer wavelength light. Many risk factors may facilitate the onset of this iatrogenic disease following surgery. Many aspects of the retinal damage are still poorly understood. Many mid light-induced retinal injuries probably remain undiagnosed in routine postoperative examination. Current appropriate light filters are not the definitive solution. Appropriate precautions should be taken during both anterior segment and vitreoretinal surgery. 相似文献
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