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OBJECTIVE: To describe initial clinical symptoms attributable to microscopic polyangiitis (MPA) or polyarteritis nodosa (PAN). METHODS: We retrospectively reviewed the medical files of 72 patients (mean followup 6.7 years) with biopsy-proven MPA (n = 36) or PAN (n = 36). RESULTS: Initial manifestations were similar in both entities except for peripheral neuropathy (P = 0.02) and gastrointestinal tract involvement (P = 0.006), which were significantly more frequent in PAN, and general signs alone in MPA (8%; P = 0.02). The mean time to diagnosis was 9.8 +/- 19.4 months; 35% of the patients died and 26% relapsed; significantly more MPA than PAN patients relapsed (P = 0.03). Time to diagnosis >/=90 days was associated with a trend toward more patients relapsing (P = 0.12), but not with an increased risk of mortality. CONCLUSION: Initial symptoms of MPA and PAN are usually nonspecific and last for several months before the diagnosis is made. A longer time to diagnosis is associated with a tendency to a higher relapse rate.  相似文献   
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PURPOSE: To describe our experience with endovascular stent-graft repairs in the thoracic aorta focusing on the secondary complication of type A dissection. METHODS: Between January 1996 and April 2004, 73 patients were treated for traumatic thoracic aortic rupture (n=15), type B dissection (n=22), or atherosclerotic descending thoracic aortic aneurysms (TAA, n=36). A retrospective review of the records found 5 (6.8%) patients (3 men; median age 64 years, range 43-87) who experienced a type A dissection at a median 20 days (range 2-124) after thoracic stent-graft repair for 3 type B dissections, 1 TAA, and a late type I endoleak that appeared 28 months after initial stent-graft repair of a traumatic dissection. RESULTS: In 3 patients (2 dissections, 1 endoleak), a tear in the aortic wall at the proximal stent-graft was responsible for a retrograde type A dissection. Underlying disease was the cause of the type A dissection in the 2 other patients (1 dissection, 1 TAA) and was unrelated to the stent-grafts. Three patients underwent open surgery at 3, 26, and 124 days after stent-graft placement; 2 procedures were successful, but the third patient died 3 months later due to multiorgan failure. Two type A dissections were untreated: one patient died from cardiac tamponade 14 days after successful stent-graft exclusion of the type I endoleak; the other patient refused further treatment and survived. The procedure-related mortality following acute retrograde type A dissection was 40%. CONCLUSIONS: Endovascular stent-graft repair of the thoracic aorta is associated with lower morbidity and mortality rates than surgical repair, although potentially lethal complications, acute or delayed, may occur.  相似文献   
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Patients with postinfarction ventricular septal rupture have poor residual or collateral blood flow in the infarct artery and do not benefit from ischemic preconditioning. This suggests that rupture of the ventricular septum occurs on an unprotected and unprepared myocardium.  相似文献   
35.

Objective

To compare long and short durations of adjunctive cyclophosphamide for the treatment of severe Churg‐Strauss syndrome (CSS).

Methods

In this prospective multicenter therapeutic trial, 48 patients with CSS with at least 1 poor‐prognosis factor at baseline were treated with glucocorticoids and either 12 or 6 intravenous cyclophosphamide pulses.

Results

At 8 years, complete remission rates and severe side effects of therapy were comparable for both groups. The overall difference in relapses was not significant between the 12‐pulse and the 6‐pulse regimens (P = 0.07), but when considering only the number of mild relapses this difference became statistically significant (P < 0.02). Although the total number of inclusions was not reached, the study was stopped prematurely in response to the superiority of the 12‐pulse regimen.

Conclusion

We concluded that 12 cyclophosphamide pulses were better able to control severe CSS than a 6‐pulse regimen. The optimal duration of therapy remains to be determined.  相似文献   
36.
A new species Kudoa azevedoi sp. n. (Myxozoa, Multivalvulida) is described in Trachurus trachurus Linnaeus, 1758 (Carangidae) from fishing harbors in Tunisian coasts using spore morphology and SSU rDNA sequence data. The parasite occurs only in ovaries within oocytes of mature and immature specimens. Spores are quadrate in shape in apical view with rounded edges, having four shell valves and four symmetrical polar capsules. They are of small sizes and measure 3.5?±?0.41 (3–4.2)?×?4.5?±?0.44 (4–5.2) length by width. The polar capsules are pyriform in shape measuring 1.5?±?0.22 (1.5–2)?×?0.75?±?0.14 (0.5–1)?μm. Infected oocytes are hypertrophied, whitish colored, and filled with mature spores. Plasmodia are tubular and ramified from the inner membrane toward the center of the oocyte. Phylogenetic analysis based on small subunit ribosomal DNA sequences shows the highest similarity (96 %) with the ovary parasite Kudoa ovivora. Some morphological details and spore dimensions support the creation of a new species in the genus Kudoa. Mean prevalence among examined females is of about 55.5 %. It varies between localities and length of fish. The present myxosporea is the second Kudoa species reported in fish ovaries.  相似文献   
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Extracellular matrix (ECM) scaffolds have been used to enhance anterior cruciate ligament (ACL) repair in large animal models. To translate this technology to clinical care, identifying a method which effectively sterilizes the material without significantly impairing in vivo function is desirable. Sixteen Yorkshire pigs underwent ACL transection and were randomly assigned to bridge‐enhanced ACL repair—primary suture repair of the ACL with addition of autologous blood soaked ECM scaffold—with either (i) an aseptically processed ECM scaffold, or (ii) an electron beam irradiated ECM scaffold. Primary outcome measures included sterility of the scaffold and biomechanical properties of the scaffold itself and the repaired ligament at 8 weeks after surgery. Scaffolds treated with 15 kGy electron beam irradiation had no bacterial or fungal growth noted, while aseptically processed scaffolds had bacterial growth in all tested samples. The mean biomechanical properties of the scaffold and healing ligament were lower in the electron beam group; however, differences were not statistically significant. Electron beam irradiation was able to effectively sterilize the scaffolds. In addition, this technique had only a minimal impact on the in vivo function of the scaffolds when used for ligament healing in the porcine model. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1015–1023, 2015.  相似文献   
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