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1.
OBJECTIVE: To evaluate the mid-term results of endovascular stent-grafting for type B aortic dissection, in comparison with those of standard medical therapy in uncomplicated cases. METHODS: Between January 1999 and 2004, among 56 patients (mean age 59.5+/-11.5 years) with type B aortic dissection, hypotensive medical therapy was the only treatment in 28 uncomplicated cases, (group A), while stent-graft implantation was performed in 28 patients with uncontrolled hypertension, persistent pain or evidence of dissection progression or complication (group B). In 14 cases (50%) the procedure was performed in an acute setting. Stent-grafting procedures were monitored with intraoperative trans-esophageal echocardiography and cine-angiography. CT scan and trans-esophageal echocardiography were performed before hospital discharge, at 6 and 12 months and then yearly. RESULTS: Follow-up (range 1-61 months, average 18.1+/-16.9 months) was 100% complete. In-hospital mortality was 10.7% (three patients, all belonging to Group B; P=0.24). No spinal cord injuries were observed. Early endoleak occurred in one patient (3.5%). Mid-term mortality was lower in Group B, although the difference was not significant (10.7 versus 14.3% in Group A, P=0.71). Follow-up CT scans evidenced complete thrombosis of the false lumen in 75% cases in Group B, 10.7% in Group A (P=0.0001), and an aneurismal dilatation of the descending aorta in 3.5% cases in Group B, 28.5% in Group A (P=0.02). CONCLUSIONS: Although with still considerable early mortality, endovascular stent-graft implantation is an effective option for the treatment of complicated type B aortic dissection. Endovascular treatment achieved a better mid-term fate of the descending thoracic aorta than medical therapy alone, even in patients with worse preoperative conditions.  相似文献   
2.
Objective: Endothelial dysfunction represents a critical early component of organ injury following cardiopulmonary bypass. Recent studies demonstrate that the treatment with atorvastatin is associated with a significant improvement of endothelial function independently of its efficacy on cholesterol levels. Therefore, we investigated the effects of preoperative atorvastatin treatment on endothelium function after coronary surgery. Methods: Forty patients undergoing coronary surgery were randomized to treatment with atorvastatin (20 mg/die; N = 20) or placebo (N = 20) 3 weeks before surgery. Twenty normal patients served as control group. The flow-mediated dilations (FMD) of the brachial artery after both reactive hyperemia (endothelium dependent) and nitroglycerin administration (endothelium independent) were evaluated at baseline, at 48 h, and 5 days postoperatively. Results: At baseline, the endothelium-dependent FMD was significantly attenuated in coronary versus normal patients (normal 10.3 ± 1.8% vs coronary 4.1 ± 1.6%, p < 0.01). At 48 h postoperatively all patients exhibited a reduced FMD compared with baseline values: the endothelium-dependent dilatation showed a drop of 60.1 + 15% in the patients of the placebo group compared with 45.8 + 16.6% (p < 0.05) those in the atorvastatin group. At the univariate analysis, no significant correlation was found between serum levels of either total cholesterol or HDL cholesterol and FMD. The nitroglycerin-induced dilation was not significantly influenced by extracorporeal circulation as well as by atorvastatin treatment. Conclusions: The endothelial dysfunction following cardiopulmonary bypass is improved by the treatment with atorvastatin, by a mechanism unrelated to the drug efficacy of controlling serum cholesterol levels.  相似文献   
3.
Subjective symptoms and experiences were explored within a group of 146 severe, chronic bronchitis and emphysema patients. Eighty-nine symptoms and experiences, derived from initial interviews with 29 patients, were rated according to the frequency of occurrence during breathing difficulties. Key cluster analyses were used to derive a Bronchitis-Emphysema Symptom Checklist (BESC) measuring 11 symptom categories: Helplessness-Hopelessness, Decathexis, Fatigue, Poor Memory, Peripheral-Sensory Complaints, Dyspnea, Congestion, Sleep Difficulties, Irritability, Anxiety, and Alienation. The BESC symptom categories are highly reliable and the relationships among categories are stable across two subgroups of patients. The BESC provides one way to describe how patients cope with and experience chronic bronchitis and emphysema.  相似文献   
4.
A uterine leiomyosarcoma that became positive for HMB45 in the metastasis   总被引:1,自引:0,他引:1  
Uterine smooth muscle tumors are usually spindle cell lesions, but a minority is composed of epithelioid cells. Foci of clear cells can be found in these latter tumors. Recently, it has been shown that some of these tumors can be positive for HMB45, and some authors have advocated calling these lesions perivascular epithelioid cell (PEC) tumors or PEComas. The case we describe here clearly shows that the so called PEC is just a smooth muscle cell capable of changing its immunophenotype. The patient involved is a 29-year-old black woman who was found to have an epithelioid leiomyosarcoma of the uterus in November 1995. She was treated with a simple hysterectomy and bilateral salpingo-oophorectomy. A metastatic lesion was found in her liver. She, therefore, also received chemotherapy and was free of disease until October 2002, when a recurrent tumor was detected in her spine. After undergoing resection of the lesion at 2 different times, in 2002 and 2003, the patient was treated with radiotherapy and is currently receiving chemotherapy. On microscopic examination, the tumor in the uterus and liver both proved to be an epithelioid leiomyosarcomas that was diffusely positive for smooth muscle actin. Approximately 15% of the cells had clear cytoplasm, but sections from 2 different blocks were completely negative for HMB45. However, although the tumors resected from the spine in 2002 and 2003 showed features similar to those of the uterine neoplasm, but with a lower percentage of cells positive for smooth muscle actin and more clear cells, several of the clear cells were positive for HMB45. To the best of our knowledge, this is the first case of a uterine smooth muscle cell tumor that became positive for HMB45 when it metastasized.  相似文献   
5.
This study analyzes the pathologic and molecular features of 5 cases of primary cutaneous large B-cell lymphoma of the leg (PCLBCL-leg), recently included in the European Organization for Research and Treatment of Cancer (EORTC) classification of primary cutaneous lymphoma. PCLBCL-leg accounts for 5% to 10% of all primary cutaneous B-cell lymphoma (PCBCL), usually affects elderly patients and carries a worse prognosis than other forms of PCBCL. It has been proposed that the malignant cells of PCLBCL-leg originate from germinal center (GC)-related cells, but their effective normal counterpart is unclear, and the rationale behind the inclusion of this lymphoma as a separate entity is based on its prognosis rather than on its proved histogenesis. All of our cases of PCLBCL-leg morphologically resembled diffuse large B-cell lymphoma (DLBCL), but to better define their histogenesis, we also analyzed various phenotypic and genotypic markers, including mutations of the Ig and of BCL-6 genes, as well as expression of the bcl-6, MUM1, and CD138/syndecan-1 proteins. Immunohistochemically, all of our cases stained for the L-26/CD20cy and CD79a antigens and expressed the bcl-2, bcl-6, and MUM-1 proteins but were negative for both the CD10/CALLA and CD138 antigens. With respect to molecular analysis, the lymphoma population of all PCLBCL-leg carried hypermutation of Ig genes, and all but 1 case also harbored mutations of the BCL-6 gene. Our results indicate that PCLBCL-leg are similar both under the morphofunctional and molecular profiles to most DLBCL of other sites. Thus, caution seems justified before definitely considering PCLBCL of the leg as a distinct entity.  相似文献   
6.
Adenoid Cystic Carcinoma of the Breast   总被引:6,自引:0,他引:6  
Twelve cases of pure adenoid cystic carcinoma of the breast were reviewed. Patients ranged in age from 34 to 69 years. Seven carcinomas were in the right breast, and five in the left; five of the 12 were located in the central region of the breast, five in the upper outer quadrant, and the two in the upper inner and lower inner quadrants, respectively. Average diameter of the primary tumors was 2.5 cm (range, 0.7 to 6.0). We graded the tumors according to a system used for adenoid cystic carcinoma of the salivary gland: five tumors were grade I, six were grade II, and one was grade III. An average of 5 years after diagnosis, all patients with grade I tumors were either alive without evidence of disease or had died of unrelated causes. Among the six patients with grade II tumors, one developed a local recurrence 5 years after diagnosis and subsequent pulmonary metastasis, and one died of metastatic adenoid cystic carcinoma 13 years after diagnosis. The one patient with grade III tumor had shown metastases in axillary lymph nodes at mastectomy, and she died of disease 2 years later. These findings suggest that the grading of adenoid cystic carcinoma of the breast may be important in prognosis and treatment selection.  相似文献   
7.
8.
Ovarian steroid cell tumors, not otherwise specified (SCTs, NOS) are uncommon sex cord-stromal tumors that may be difficult to distinguish from other oxyphilic or clear-cell neoplasms. Immunohistochemical staining for inhibin, although generally useful in the diagnosis of SCTs, NOS, is not positive in every case and not all laboratories have this marker available. Recently, it has been reported that calretinin is expressed by sex cord-stromal tumors. We studied six SCTs, NOS for both calretinin and inhibin expression to evaluate the sensitivity of calretinin in comparison to inhibin. We also tested for CD99, Melan-A (A103), and S-100, other markers reported to be positive in these tumors. HMB-45 and MART-1 (Ab3) completed our panel of markers. All six tumors were positive for both calretinin and inhibin. Calretinin positivity was present in 60% to >90% of tumor cells, whereas inhibin reactivity ranged from <5% to >90% of tumor cells. Membranous staining for CD99 was present in one tumor. S-100-positive cells were seen in two tumors, whereas four tumors were immunoreactive for HMB-45. All six tumors were positive for Melan-A (A103), but in general the staining was less diffuse than with calretinin. All of the tumors were essentially negative for MART-1 (Ab3). The consistent diffuse staining of the tumors in this study for calretinin, in comparison to inhibin and Melan-A (A103), suggests that it is a sensitive marker for SCTs, NOS. MART-1 (Ab3) immunostaining may be useful for cases in which melanoma is considered in the differential diagnosis.  相似文献   
9.
PURPOSE: A drug utilization trial was performed to investigate acute versus short-term effects after switching or adding bimatoprost in open-angle glaucoma patients over a 3- month observation period. METHODS: One (1) eye was randomly chosen from 47 glaucomatous patients (abnormal visual field and/or abnormal optic nerve and intraocular pressure (IOP) above 21 mmHg without treatment). Only patients who did not reach the target IOP with their ongoing treatment were recruited in this study. IOP was measured at baseline, after 1 hour, and 2 hours from the first instillation and after 1 week, 1, and 3 months of treatment. RESULTS: The IOP before bimatoprost administration was 20.16+/-3.6 mmHg (mean+/-standard deviation). There was no statistically significant decrease of IOP after 1 hour (mean IOP, 19.96+/-4.25 mmHg) and after 2 hours (mean IOP, 17.73+/-3.24 mmHg). Statistically significant (p<0.001) decreases after 1 week (mean IOP, 16.48+/-2.9 mmHg), after 1 month (mean IOP, 16.48+/-2.9 mmHg) and after 3 months (mean IOP, 16.15+/-2.7 mmHg) were found. CONCLUSION: The results suggested that bimatroprost had a significant acute effect on IOP in monotherapy, while no significant effect was found when the therapy was switched or added. The effect for primary open-angle glaucoma was very evident. There was no specific side effect attributable to combining bimatoprost with any of the treatments in use.  相似文献   
10.
Nowadays, manufacturing industries have to shorten the time to market in order to satisfy needs of customers and to survive in global competitive markets. For these reasons a new type of product data development and management is necessary. The Product Lifecycle Management (PLM) is an emerging philosophy to improve strategic engineering for managing information, processes and resources to support the life cycle of a product, from its conception, development, launch and the withdrawal. The well-established technologies CAD / CAE / CAM are fundamental part of it, although their interactions may be only partially involved. The paper takes into account open questions regarding the relationship between models and simulations and new possible scenarios related to their integration starting from a complete and multi-disciplinary case-test involving the virtual-experimental deliverable process of the fatigue life prediction and related structural modification design applied to a suspension cab for truck vehicle.  相似文献   
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