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1.
目的:明确集中的电话干预能否降低慢性心衰门诊患者死亡或因心衰加重而住院的发生率。设计:多中心、随机对照试验。地点:阿根廷的51个中心(包括公立、私立的医院及流动设施)。参与者:1518例患有稳定的慢性心衰且已接受最佳药物治疗方案治疗的门诊患者,由心脏科主治医师分层后随机分为电话干预组和常规治疗组。干预:在常规治疗的基础上,由一个中心通过护士频繁的电话随访对患者进行教育、辅导和监督。主要观察指标:全因死亡或由于心衰加重而住院。结果:99.5%的患者完成了全部随访。常规治疗组758例患者中由于心衰加重而住院或死亡的比例(235…  相似文献   
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Multiple sclerosis: serial study of gadolinium-enhanced MR imaging   总被引:4,自引:0,他引:4  
Thirteen patients with definite multiple sclerosis (MS), studied 16-24 months previously with magnetic resonance (MR) imaging with and without enhancement by intravenously administered gadolinium diethylenetriaminepentaacetic acid (DTPA) dimeglumine, were reexamined with a similar protocol. Assessment of enhancement and clinical activity in both studies revealed that enhancement was observed in 13 of 14 cases in which clinical activity had changed within 4 weeks of the study and thus appeared more sensitive than clinical examination in determining active disease. The 3-minute postinjection, short repetition time image (TR) was the most efficient for depicting enhancement. Enhancing lesions (active plaques) arose from previously hyper- or isointense regions on long TR images. Previously active lesions reverted to areas of iso- or hyperintensity on long TR images. Serial comparison of long TR images in this population reveals a decrease in high-intensity lesions on long TR images in some cases and an increase in others. The findings of high-intensity regions on long TR images and previously enhancing lesions both becoming isointense suggests that transient inflammatory changes with concomitant edema without demyelination and/or with significant remyelination may occur in some MS lesions. MS lesions are dynamic; both active and inactive lesions may show dramatic change on longitudinal MR imaging studies.  相似文献   
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Corticosteroids are a mainstay of topical therapy for psoriasis. While efficacious and relatively safe when used carefully, the potential for side effects, notably skin atrophy and adrenal suppression, have been associated with excesses in potency, prolonged or widespread use. The International Psoriasis Council Working Group on Topical Therapy has reviewed the efficacy and safety of topical corticosteroids and recommends strategies for safe, long‐term use of these agents.  相似文献   
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A case of hypochloraemic metabolic alkalosis in an infant with chloride losing ileostomy drainage and cystic fibrosis is described. It is speculated that intestinal loss of chloride played a major role in the development of metabolic alkalosis.  相似文献   
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Cervical internal carotid artery dissecting hemorrhage: diagnosis using MR   总被引:7,自引:0,他引:7  
Two men underwent high-resolution magnetic resonance (MR) imaging of the internal carotid artery (ICA) 12 and 16 days after spontaneous dissection of this vessel. One underwent follow-up MR imaging 7 weeks later. T1-weighted images were obtained in both cases, and T2-weighted images were obtained in one patient. In both cases, the MR findings corresponded to the angiographic abnormalities. On both the T1- and T2-weighted images, there was a hyperintense lesion expanding the wall and narrowing the lumen of the ICAs. Follow-up MR imaging showed complete resolution of the mural lesion. Axial images best demonstrated the anatomic and MR signal alterations. The hyperintensity of the lesion on both T1- and T2-weighted images indicated a short T1 and a long T2 as expected in a subacute hematoma. High-resolution MR imaging, therefore, can specifically demonstrate a thrombosed carotid dissection noninvasively at least as early as 12 days. The potential to diagnose carotid dissection in the acute phase using high-field-strength MR imaging and its importance for the prevention of embolic strokes are also discussed.  相似文献   
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Occult cerebral vascular malformations: high-field MR imaging   总被引:4,自引:0,他引:4  
Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions.  相似文献   
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The T(c)-cell response to ectromelia virus infection was studied in BALB/c-H-2(db) mice which carry a loss mutation in the H-2D region that results in the absence from cell surfaces of a molecule (D’) bearing certain public H-2 specificities. When infected, these mice showed a poor response of T(c) cells that recognize H-2D(d) plus virus-specific determinants on infected macrophage targets, but gave a normal response to H-2K d plus virus-specific antigens. However, their own infected macrophages do display wild-type antigenic patterns involving virus and H-2D(d) since they were killed as efficiently as wild-type (BALB/c,H- 2(d))-infected cells by T(c) cells specific only for H-2D(d) plus viral antigens. When tested in vitro, infected BALB/c-H-2(db) cells stimulated a poor T(c)-cell response to H-2D plus virus-specific antigens, but stimulated a normal response (in comparison with infected BALB/c macrophages) to H-2K(d) plus viral antigens. Uninfected BALB/c-H-2(db) cells stimulated a normal T(c)-cell response to minor H antigens or trinitrophenyl in association with H-2D(d), thus suggesting that the defective response to infection may reside in a failure of the relevant H-2D(d) antigens of mutant cells to physically associate with viral antigens. Close association of viral and H-2D-coded molecules was also suggested by ability of specific anti-H-2K or -H-2D to partially block T(c)-cell-mediated lysis of infected targets. These results were interpreted to mean that H-2Dd-dependent, virus- immune T(c) cells recognized an antigenic pattern consisting of virus- specific and H-2D(d) determinants with the latter borne on an H-2D molecule carrying serologically-defined H-2D(d) private specificities. A second H-2D(d)-coded molecule (D’) was not required for recognition and lysis by activated T(c) cells, but was apparently necessary for efficient stimulation of precursor T(c) cells, perhaps by promoting appropriate physical association of viral and H-2D(d) molecules.  相似文献   
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