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991.
The longstanding compression-relaxation effects of myocardial bridging may produce endothelial dysfunction by direct stress on the endothelium. We tested the hypothesis that myocardial bridging induces endothelial dysfunction and subsequently increases the risk of coronary spasm and investigated the symptomatic response to medication in patients with documented myocardial bridging and coronary spasm. In 81 patients with myocardial bridging (44 men; mean age 57.2 years) and 195 control patients without bridging and atherosclerotic lesions confirmed by angiography (97 men; mean age 58.4 years), spasm provocation testing was done by incremental acetylcholine infusion into the left coronary artery. Spasm was documented in 62 of 81 patients with bridging and in 31 of 195 controls (p <0.001). A focal spasm was limited to the bridging segments compared with controls (p <0.001). In conclusion, the results of this study showed that myocardial bridging increased the risk of coronary spasm by endothelial dysfunction in the bridging segment.  相似文献   
992.
Tuberculosis may affect primarily all organs and tissues of the body, although some of these show high immunity against the infection. The most common forms of non-pulmonary tuberculosis are tuberculosis of bones and joints (30%), urinary system (24%), lymph nodes (13%), sexual organs (8%), cerebrospinal meninges (4%), and alimentary system (3%). Especially, the commonest presentation of abdominal tuberculosis is ileocecal disease, but isolated appendicular involvement is also rarely seen, occurring in only 1.5% to 3% of cases in the absence of pulmonary or other abdominal involvement. The appendix may either be involved secondary to ileocecal tuberculosis, or to tuberculosis at another site within the abdomen, or may occur in the even, rarer "isolated" form, without the evidence of disease elsewhere. We report a case of acute appendicitis underwent appendectomy and histopathologic examination of appendix revealed appendicular tuberculosis.  相似文献   
993.
Epithelioid hemangioendothelioma is a rare vascular origin tumor which usually occurs in soft tissues, liver, and lung. It usually affects adult women and presents as multiple hepatic nodules with mainly peripheral distribution. It is difficult to diagnose and treat because of non-specific clinical manifestations and findings on the imaging study. Moreover, pathological misdiagnosis is common. We report a case of this rare tumor that was detected incidentally. Final diagnosis was based on histological evidence. A 52-years old man suffered from right upper quadrant abdominal pain for 3 months, and was initially misdiagnosed as a metastatic carcinoma. Physical examination revealed superior cervical lymphadenopathy with mild hepatomegaly. Finally, hepatic epithelioid hemangioendothelioma was diagnosed on the basis of positive immunohistochemical staining for factor VIII, CD34, and VEGF. Our case highlights the importance of a histological diagnosis to avoid misdiagnosis.  相似文献   
994.
Tissue Doppler imaging (TDI) is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular (LV) systolic and diastolic function. Recent studies have explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as heart failure, acute myocardial infarction, and hypertension. In these conditions, myocardial mitral annular or basal segmental (Sm) systolic and early diastolic (Ea or Em) velocities have been shown to predict mortality or cardiovascular events. In particular, those with reduced Sm or Em values of <3 cm/s have a very poor prognosis. In heart failure and after myocardial infarction, noninvasive assessment of LV diastolic pressure by transmitral to mitral annular early diastolic velocity ratio (E/Ea or E/Em) is a strong prognosticator, especially when E/Ea is > or =15. In addition, systolic intraventricular dyssynchrony measured by segmental analysis of myocardial velocities is another independent predictor of adverse clinical outcome in heart failure subjects, even when the QRS duration is normal. In heart failure patients who received cardiac resynchronization therapy, the presence of systolic dyssynchrony at baseline is associated with favorable LV remodeling, which in turn predicts a favorable long-term clinical outcome. Finally, TDI and derived deformation parameters improve prognostic assessment during dobutamine stress echocardiography. A high mean Sm value in the basal segments of patients with suspected coronary artery disease is associated with lower mortality rate or myocardial infarction and is superior to the wall motion score.  相似文献   
995.
Stent thrombosis is a feared complication of percutaneous coronary intervention, although there is a low incidence of thrombotic events following drug-eluting stent implantation. We report a case with cardiogenic shock complicated by acute myocardial infarction due to simultaneous subacute stent thrombosis occurring 3 days after implantation of two sirolimus-eluting stents in the proximal left anterior descending artery (LAD) and in the proximal right coronary artery (RCA).  相似文献   
996.
997.
Angiosarcoma is a rare malignant tumor which occurs frequently in the skin and soft subcutis. Moreover, primary gastrointestinal angiosarcomas are very rare. This tumor manifests as non-specific symptoms such as gastrointestinal bleeding, abdominal pain and nausea. The diagnosis is often made at an advanced stage. Surgery, chemotherapy and radiotherapy are the mainstay of treatment. However, the prognosis is very poor. We report a case of primary angiosarcoma of the small intestine presenting as recurrent gastrointestinal bleeding. A 54-year-old man was admitted with recurrent gastrointestinal bleeding. An abdominal CT scan revealed an ileo-ileal intussusception. Segmental resection was performed with ileo-ileal anastomosis. The ileal mass was diagnosed as angiosarcoma on immunohistochemical stain. He received 3 cycles of chemotherapy, but died 5 months after the diagnosis.  相似文献   
998.
Many patients suffering from breast carcinoma have metastases at initial diagnosis. The common metastatic sites are skeleton, liver and lung. Metastases to stomach are rare and only three cases have been reported in Korea. The endoscopic features of gastric metastases from breast carcinoma can be divided into three main categories: diffuse infiltration, external compression, and localized tumor deposition with ulceration or with a polypoid mass. However, metastatic gastric lesions which resemble early gastric carcinoma are rare. Typically, gastric metastases are confined to submucosa and muscularis, so that mucosal biopsy specimens might be false-negative. We report a case of gastric metastasis from infiltrative lobular carcinoma of the breast in a 66-year-old woman who had undergone left mastectomy with postoperative radiotherapy 17 years earlier. Initial diagnosis was early gastric carcinoma, signet ring cell type on gastric biopsy findings. However, definitive diagnosis of metastatic breast cancer was confirmed after endoscopic mucosal resection of a presumed primary early gastric carcinoma.  相似文献   
999.
ObjectivesThe VIVA (Valve in Valve) trial was designed to systematically and prospectively collect data regarding the use of transcatheter aortic valve replacement in patients with failing surgical aortic bioprostheses at high-risk for reoperation.BackgroundSurgical aortic valve replacement has been the standard of care in symptomatic patients with aortic valve disease. However, bioprosthetic valves degenerate over time, requiring redo surgery.MethodsVIVA is an international, observational, single-arm, postmarket study conducted at 23 sites that enrolled 202 patients with symptomatic degeneration of an aortic bioprosthesis eligible for elective treatment with a CoreValve or Evolut R self-expanding transcatheter aortic valve.ResultsPatients were elderly (mean age 79.9 years), 47.5% were men, and they had a mean Society of Thoracic Surgeons score of 6.6%. Although 41.8% of patients had surgical bioprostheses with labeled size ≤21 mm, valve hemodynamic parameters were markedly improved from baseline (mean aortic valve gradient 35.0 ± 16.3 mm Hg) to discharge (17.5 ± 8.6 mm Hg) and were sustained at 1 year (15.5 ± 7.5 mm Hg). At 1 year, total aortic regurgitation greater than mild was measured in 1.1% of patients. Clinical outcomes at 30 days demonstrated low mortality (2.5%), no disabling strokes, a 0.5% rate of acute kidney injury, and an 8.0% rate of new pacemaker implantation. At 1 year, the mortality rate remained low (8.8%), with 1 disabling stroke (0.6%). Five patients (2.5%) experienced coronary artery obstructions, 3 during and 1 immediately after the procedure and 1 several months later.ConclusionsDegenerated surgical bioprostheses can be safely treated with the CoreValve or Evolut R platform using the catheter-based valve-in-valve procedure. Excellent 1-year clinical and hemodynamic outcomes were achieved in this real-world patient population. (CoreValve VIVA Study Evaluation of the Clinical Outcomes of CoreValve in Degenerative Surgical Aortic Bioprosthesis; NCT02209298)  相似文献   
1000.
The E3L gene product found in all poxviruses is required for the lethality of mice in vaccinia virus infection. Both the C-terminal region, consisting of a double-stranded RNA-binding motif, and the N-terminal region (vZ(E3L)), which is similar to the Zalpha family of Z-DNA-binding proteins, are required for infection. It has recently been demonstrated that the function of the N-terminal domain depends on its ability to bind Z-DNA; Z-DNA-binding domains from unrelated mammalian proteins fully complement an N-terminal deletion of E3L. Mutations that decrease affinity for Z-DNA have similar effects in decreasing pathogenicity. Compounds that block the Z-DNA-binding activity of E3L may also limit infection by the poxvirus. Here we show both an in vitro and an in vivo assay with the potential to be used in screening for such compounds. Using a conformation-specific yeast one-hybrid assay, we compared the results for Z-DNA binding of vZ(E3L) with those for human Zbeta(ADAR1), a peptide that has similarity to the Zalpha motif but does not bind Z-DNA, and with a mutant of hZbeta(ADAR1), which binds Z-DNA. The results suggest that this system can be used for high-throughput screening.  相似文献   
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