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Antisynthetase syndrome (AS) is a rare disease that affects patients with inflammatory myopathies such as polymyositis (PM) and dermatomyositis (DM). In patients with AS, up to 95% of patients develop antisynthetase syndrome-associated interstitial lung disease (AS-ILD). Although AS-ILD commonly occurs in patients with a well-established diagnosis of AS, it can be the first or only manifestation of an occult AS. The frequency of interstitial lung disease (ILD), myopathy, and skin involvement are often dependent on the type of myositis-specific antibodies present. AS-ILD patients who are positive for both anti-Jo-1 and anti-SSA/RO-52 autoantibodies often present with a severe degree of lung restriction on pulmonary function tests and radiologic imaging with an inadequate response toward immunosuppressive therapies. We describe a 65-year-old woman who presents with chronic dyspnea. She was initially diagnosed with corticosteroid-resistant cryptogenic organizing pneumonia based on the radiological findings on her CT chest. Her symptoms did not improve, and she suffered from intolerable corticosteroid-related side effects. Reviews of systems were positive for arthritis and Raynaud's phenomenon. She was found to have elevated inflammatory markers and autoantibodies such as anti-Jo-1, anti-RO-52, and anti-SSA. A diagnosis of AS-ILD resistant to corticosteroid therapy was made. Her lung function improved with combination therapy of mycophenolate and rituximab. Our case highlights that a detailed history and physical exam, compatible radiologic imaging, and autoantibodies are essential for the diagnosis of AS-ILD.  相似文献   
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The effects of manganese chloride (MnCl2) and verapamil on automaticity of digitlazied Purkinje fibers were studied using conventional microelectrode techniques. The stduied wer made in isolated, spontaneously beating Purkinje prearations. Quabain alone consistently increased the automatic rate, whereas no such increase was observed when the preparations were superfused with a mixture of ouabain adn MnCl2. MnCl2 was also shown to be effective is suppressing the enhanced automaticity induced by ouabain. Mncl2 alone did not have a significant effect on the spontaneous rate of Purkinje fibers. The effect of verapamil was similar to that of MnCl2 in preventing and suppressing the ouabain-induced increase in automaticity. MnCl2 and verapamil have been shown to inhibt tha slow inward calcium current of cardiac fibers. The results therefore suggest that an inward calcium ion current may play a role in the development of digitalis-induced increase in the stope of phase 4 depolarization in Purkinje fibers.  相似文献   
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There is suggestive evidence that bundle branch re-entry occurs in man in response to premature right ventricular stimulation. Demonstration of the activation sequence during re-entrant excitation in the in vivo dog was accomplished by placing recording electrodes on the major portions of the specialized conduction system. A temporary right heart bypass was utilized to place two or more electrodes on both right and left bundle branches and place electrodes on the His bundle and on the left and right ventricular endocardium. Premature excitation of the right ventricle was found not to retrogradely activate the right bundle but was able to cause slow right to left myocardial activation that resulted in retrograde activation within the left bundle branch. Retrograde conduction in the left bundle caused activation of the His bundle and the proximal right bundle. Activation of the right bundle resulted in antegrade conduction of the impulse across the site of previous conduction block and re-excitation of the right ventricle, to complete the re-entrant circuit. This type of re-entry, utilizing the bundle branches, was demonstrated in 19 dogs. This re-entry circuit was found to be facilitated by shortening of the right ventricular refractory period by local epicardial warming and was abolished by interruption of conduction in the right bundle by anodal blocking current applied to the right bundle. The sites of slow conduction, site of unidirectional block, and pathways of conduction were demonstrated. The validity of the concept of re-entry occurring within the specialized conduction system is substantiated.  相似文献   
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Conventional wisdom dictates that autogenous tissue interposition be used in contaminated wounds when direct vascular repair is not feasible. Although there are few reports of successful use of PTFE grafts in grossly contaminated wounds, doubt still exists regarding the use of any prosthetic material in such wounds for reconstruction of vascular injury. Twenty-five vascular reconstructions were performed in 20 patients during a 3.5 year period. These patients had life-threatening multiple trauma and severe local tissue damage along with their arterial and venous injuries in open contaminated wounds after blunt (16 patients) and penetrating (4 patients) trauma. In all patients, 6 mm PTFE was used for interposition bypass for arterial injuries, and in five of these patients, 8 mm PTFE was used for concomitant venous interposition bypass. One patient died and there was one arterial and one venous graft thrombosis in the same patient 3 months after a shotgun blast injury to the groin, but there was no limb loss. All other grafts remained patent without wound infection, sepsis, or anastomatic disruption. Under the circumstances of these peripheral vascular injuries, PTFE was an acceptable choice for primary reconstruction in our patients. Its ready availability in many calibers, sparing of autogenous vein for future use, and its expedience in vascular reconstruction comprise the advantages of using PTFE in multiply traumatized patients without producing the feared evidence of infected prosthetic grafts.  相似文献   
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One hundred thirty cirrhotic patients who had portal decompressive procedures were reviewed. Progressive hepatic failure, bleeding diathesis and shock or unsatisfactory operations accounted for the 90 day operative mortality of 36 percent. Many deaths occurred after emergency operations in which delay before surgery, increased operative time and intraoperative blood loss resulted in a higher incidence of hepatic failure and coagulopathy. Of the deaths related to unsatisfactory operations, technical difficulties resulting in massive hemorrhage, inadequate shunts and leaking gastrostomies were the causes. Of the various procedures, only the portacaval H-graft was not attended by any of the complications that resulted in massive intraoperative hemorrhage.Operative mortality may be reduced by early and expeditious operation in patients with actively bleeding cirrhosis, because massive blood loss and lengthy operations would result in further hepatic dysfunction because of splanchnic hypoperfusion. Of the standard total portal decompressive procedures, the portacaval H-graft may be the operation of choice because it precludes extensive venous mobilization while shunt adequacy and patency are excellent. Furthermore, decompressive gastrostomy is contraindicated in such patients. Reduction of operative mortality by such measures might result in a more realistic appraisal of long-term results in the surgical management of portal hypertension in patients with cirrhosis.  相似文献   
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Midbrain tegmental intracranial self-stimulation (ICSS) was not attenuated by ipsilateral or bilateral locus coeruleus lesions. Certain of these lesions were followed by histochemical confirmation that the majority of locus coeruleus neurons was destroyed, and biochemical evidence that over 80% of the cortical norepinephrine was depleted. To test the possibility that the surviving ICSS was due to stimulation of another norepinephrine system, histochemically verified ipsilateral or bilateral lesions of the ventral norepinephrine bundle were administered to a second group of midbrain tegmental ICSS animals. These lesions resulted in marked loss of body weight, but had no effect on ICSS. In a third experiment, lesions were made in the medial forebrain bundle (MFB) ipsilateral to midbrain tegmental ICSS electrodes. These lesions resulted in attenuation of ICSS which was directly proportional to the extent of MFB damage. On the basis of these data alone, however, it was not possible to identify the ciritical fibers supporting ICSS. It was oncluded that the locus coeruleus does not play a necessary role in midbrain tegmental ICSS.  相似文献   
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We were concerned about the precision (i.e., consensus as to meaning) of adjectives and adverbs used to express frequency in the medical literature. We asked 103 physicians and 106 nonphysicians to assign to each of 22 such modifiers a percentage representing their understanding of the term. As indexed by the standard deviations, the degree of imprecision for 17 terms was so great for both physicians and for laymen as to make their use unacceptable. Consensus was significantly less among laymen than among physicians for 10 of the terms. Greater consensus was shown by native English-speaking physicians than by those with other native languages. Our data suggest further that American graduates of American medical schools show more consensus than American graduates of foreign medical schools. Board-certified physicians did not show greater consensus than physicians who were not board-certified. Verbal expressions of frequency should be eliminated from medical communications; failing that, the author should specify numerically the frequency he intends when he uses any such expression.  相似文献   
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