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71.
OBJECTIVE: We consider the short- and long-term outcomes of the repair of the isolated partial atrioventricular (AV) septal defect to determine the role played by the atypical forms on the initial AV valve replacement and on the risk of reoperation. METHODS: Two hundred and eight patients underwent an operation for this malformation between 1974 and 2001. Clinical and echocardiographic examinations were performed on all patients, the AV valve regurgitation was graded from 1 to 4 and a residual interatrial shunt was sought. Median age at the intervention was 5.8 years (3 months to 67 years). RESULTS: Median follow-up time was 7.5 years (range 0-22.6 years). The cumulative 30-day, 5- and 20-year survival rates were 96.5, 95.4 and 94.6%, respectively. AV valve replacement was associated with a high mortality (P<0.001). A reoperation was performed on 12 patients (5.7%) including six patients within less than a 30-day period, especially to repair residual AV valve regurgitation. We performed four AV valve repairs by annuloplasty and six AV valve replacements. Two patients who had initially undergone an AV valve replacement underwent a reoperation for valve thrombosis. The cumulative 30-day, 5- and 20-year rates of freedom from reoperation were 96.5, 93.6 and 83%, respectively. An atypical form was present in 24 patients (11.5%) and was a risk factor for initial AV valve replacement (P<0.001) and for reoperation (P<0.001). A complete AV block occurred in 13 patients (6.2%), all of them within a 30-day period. The AV valve replacement was a high risk factor for a complete AV block (P<0.001). At the end of our study 180 patients (96%) were in NYHA I and 8 in NYHA II. CONCLUSIONS: The morbi-mortality of the isolated partial AV septal defect is primarily perioperative and is linked with the presence of an atypical form of the lesion. This atypical form was the main reason for reoperation for AV valve regurgitation. The AV valve replacement was associated with a high mortality and with the occurrence of complete AV block. Using a standardized technique, the AV septal defect can be repaired with excellent long-term clinical and echographic results.  相似文献   
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Acute vascular occlusion after percutaneous transluminal coronary angioplasty (PTCA) often necessitates a prompt aortocoronary bypass-operation (CABG). Alternatively, a re-PTCA can be attempted. In 1500 consecutive patients there was acute symptomatic occlusion due to PTCA 5 min to 16 h after the operation in 47 cases (3.1%). An immediate re-PTCA was attempted in all cases. Results: Reopening was successful in 43 of 47 cases (91%): in 15 patients (30%) within 30 min, in 36 patients (68%) within 60 min and in 42 patients (89%) within 90 min. In eight patients there was early re-occlusion 30 min to 20 h after re-PTCA, necessitating acute CABG in four patients. In 35 patients with re-PTCA the vessel remained open. Re-stenosis occurred within 1 to 10 days in 10 patients, and in additional 12 patients after 2-4 months. In most cases an additional PTCA was successful. Complications: Six patients had an emergency CABG (three with an exchange wire as a stent in the dissected coronary artery). Three patients died (one after CABG); 14 patients experienced myocardial infarction (30%) (in three of these 14 the infarct was large). Conclusion: Acute vascular occlusion after PTCA can successfully be treated by re-PTCA in four of five cases. However a rate of re-stenosis of about 60% is to be anticipated. Reperfusion with re-PTCA is fast and in these patients with transmural ischemia there are obviously less complications in comparison to emergency CABG after PTCA. 60% of the patients remain symptom free or markedly improved and without infarction or emergency CABG after 4 months.  相似文献   
75.
A 54 year-old woman developed approximately 150 generalized glomus tumors since she had been 23 years old. Painful tumors showed more glomus cells than those being not painful. Furthermore, the patient suffered from persisting congenital capillary hemangioma (strawberry mark). Histological examination revealed that glomus cells were located in the vessel walls. The large amount of Dopa found in the glomus tumor tissue supports the assumption that it may be innervated by adrenergic efferent nerves.  相似文献   
76.
BACKGROUND: The treatment of orbital wall fractures involves observation and/or surgical reduction with repositioning of herniated orbital tissues. To prevent reherniation of tissue and development of enophthalmos, the orbital floor or wall defect is commonly covered with an alloplastic implant. Complications associated with these implants are infrequent and generally appear as isolated case reports. METHODS: The authors reviewed the files of four consultative oculoplastic surgeons and searched for individuals with complications secondary to their alloplastic implants used during orbital fracture repair. FINDINGS: Seventeen patients were identified with a variety of complications related to their alloplastic implant. CONCLUSION: Although these implants are relatively inert and develop a fibrous capsule walling them off from the surrounding orbit, they remain foreign bodies and are thus subject to possible complications at any time. The authors review the spectrum of complications occurring with various alloplastic implants.  相似文献   
77.
Investigations into the effects of prior silicone exposure on subsequent capsule formation around silicone implants assume particular relevance in light of the exponential increase in the medical application of polymers such as silicone. The inert nature of silicone has been in question with regard to its effects on the immune system, specifically whether or not it may act as a hapten or antigen. The present study analyzes the effects of prior silicone exposure on subsequent capsule formation, histological consistency, and pressures when an animal is reexposed to a silicone implant. Twelve female Lewis rats (body weight 250 g) were randomly divided into two groups. Group 1 (n = 6) rats were subcutaneously injected with 2.5 ml of Freund's Complete Adjuvant, Group 2 (n = 6) rats were injected with an equal volume of adjuvant sonicated with silicone gel. At 4 weeks a gel-filled silicone implant was placed subcutaneously in each animal. Capsule pressures were obtained at 4 months and the capsules from 3 rats from Group 2 were excised and examined microscopically. Pressures were measured again at 8 months and all remaining capsules were excised and examined. No statistically significant differences were noted when comparing two profiles over time between silicone-exposed and nonexposed animals in regard to capsule thickness or capsule pressure. However, capsule pressures were significantly lower at 8 months than at 4 months in both groups (p less than 0.034). In this model, significant reductions in capsule pressure were noted in both groups over time, but prior exposure to silicone did not appear to alter capsule histology, thickness, or pressure.  相似文献   
78.
Structural tensile properties analyses of 10-mm-wide central sections of quadriceps tendon-bone (QT-B) and bone-patellar ligament (B-PL) complexes from young male donors (mean age 24.9 years, range 19–32 years) were complemented by a cryosectional analysis: each QT-B complex was composed of the segment of the quadriceps tendon with the proximal half of the patella attached, each B-PL complex was composed of the distal half of the patella with the patellar ligament attached. A servohydraulic materials testing machine was used to assess ultimate failure load of 16 unconditioned and 16 preconditioned QT-B and B-PL complexes at an extension rate of 1 mm/s. Ligaments/tendons were preconditioned during 200 cycles from 50 to 800 N at 0.5 Hz. On cryosections the quadriceps tendons were significantly longer and thicker and exhibited a significantly larger bony attachment area than the patellar ligaments. Cross-sectional areas of 10-mm-wide, full-thickness, central parts of unconditioned quadriceps tendons were significantly greater and measured 64.6±8.4 mm2 with respect to the cross-sectional area of patellar ligament, measuring 36.8±5.7 mm2 (P<0.0025). Ultimate failure loads for unconditioned complexes resulted at 2173±618 N for QT-B complexes and at 1953±325 N for B-PL complexes (P=0.43). Ultimate failure load values measured 2353±495 N for preconditioned QT-B complexes and 2376±152 N for preconditioned B-PL complexes, respectively (P=0.77). Despite the fact that initial testing length, area of unconditioned QT-B and B-PL complexes were significantly different, displacement at ultimate load, energy to failure and total energy were not. In terms of ultimate tensile strength, the 10-mm-wide central part of the QT-B complex compared favourably to the tensile properties of the human femur-anterior cruciate ligament-tibia complex from a comparable young age group. The evidence from anatomic, cryosectional and structural properties analyses suggests that the QT-B complex may be a valuable and versatile adjunct to the surgeon's armamentarium in reconstructive cruciate ligament surgery.  相似文献   
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Cyclic amides of N alpha-arylsulfonylated 4-amidinophenylalanine are specific, highly potent inhibitors of thrombin. Introduction of amino acids between the arylsulfonyl blocking group and amino nitrogen influence particularly the antithrombin activity. By the use of glycine as spacer the compounds become tight binding thrombin inhibitors, while introduction of other omega-amino acids, Gly-Gly, L-Pro, Gly-L-Pro or L-Pro-Gly, reduces the specificity and potency of thrombin inhibition. Substitution of the arylsulfonyl blocking group for a heteroarylsulfonyl residue or an aryl residue causes a decrease in antithrombin activity, while substitution for a benzoyloxycarbonyl blocking group has only slight influence. It is concluded that the N alpha-moiety is of decisive importance for the antithrombin activity of derivatives of 4-amidinophenylalanine.  相似文献   
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