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Forty elderly patients with basicervical and pertrochanteric fractures were managed with uniplanar AO external fixator under regional anaesthetic block of the femoral nerve and lateral cutaneous nerve of the thigh from April 2003 to March 2006. The mean age of the patients was 67.9 ± 5.5 years. External fixator application was performed under radiological control after closed reduction had been obtained. Comorbid factors, duration of surgery, duration of hospitalisation, complications, walking ability, time to union and mortality rate were recorded. Patients were followed up for a mean period of 12 ± 4.5 months. Superficial pin tract infection occurred in 13 patients, healing in varus >10° and with shortening >2 cm occurred in six patients, and one patient suffered a spontaneous ipsilateral femoral neck fracture after removal of the fixator. The mean time for union was 10.4 ± 1.2 weeks. Rapid union rate and minor complications obtained in the present study are comparable to those obtained with standard internal fixation techniques. Minimal intraoperative blood loss, short operative time and early patient mobilisation are advantages signifying uniplanar external fixator application under regional anaesthetic block to be a viable option in treatment of basicervical and pertrochanteric fractures in high-risk elderly patients.  相似文献   
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OBJECTIVE: In a prospective study, the effect of thymectomy on the pulmonary status of 50 consecutive patients with myasthenia gravis was evaluated over a time range of 4 years in the Chest and Chest surgery departments in the Cairo University Clinics and Thoracic Surgery Department of the Evangelisches Krankenhaus Duisburg-Nord. METHODS: The patients were divided into two groups: Group I included 26 patients who underwent thymectomy through median sternotomy. The mean age of the patients in this group was 24.8+/-10.5 (5-41) years. They were 19 females and seven males. Thirteen of the patients were in Myasthenia Gravis Foundation of America (MGFA) class IIa, and 12 were in class IIb, and one was in class IIIa. Group II included 24 patients who underwent thymectomy through manubriotomy. The mean age of the patients in this group was 25.2+/-9.2 (12-41) years. They were 13 females and 11 males. Eight of the patients were in MGFA class 2a, 14 were in class IIb, and two were in class IIIa. RESULTS: When compared to group I in which postoperative ventilation was required in 15.4% of patients, postoperative ventilation was not necessary in patients of group II with a statistically significant difference (P=0.04). The mean duration of stay in the intensive care unit was 111.4h in group II, and 169.7h in group I (P=0.03). The peak inspiratory flow rate and the forced vital capacity were also statistically significantly better in group II. There was no mortality in both groups, and the morbidity was higher in the median sternotomy group. CONCLUSION: Thymectomy through a manubriotomy, which allows extensive removal of ectopic thymic tissue in addition to the thymus through a less invasive approach than a full median sternotomy, is associated with a significantly smoother postoperative course and less pulmonary complications, when compared with thymectomy through a full median sternotomy.  相似文献   
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Six consecutive patients with active aortic valve endocarditis, including 2 with extensive subannular aortic root abscess, were successfully treated with viable cryopreserved homograft aortic valve replacement. Two patients required extensive aortic root reconstruction with an appropriately trimmed aortic homograft to cover large abscess cavities. All patients showed resolution of infection with no perioperative mortality or clinically significant morbidity. Three patients had a minor degree of aortic insufficiency on postoperative echo-Doppler study. On follow-up at 6 to 48 months, all patients were in New York Heart Association functional class I. The resistance of the unstented homograft to infection makes it an attractive choice for patients requiring aortic valve replacement for active endocarditis. The results of surgical intervention in patients with extensive aortic root involvement may be further improved by the flexibility afforded by the homograft to be "custom-fit" to the abnormal aortic root and the ability to achieve secure abnormal aortic root and the ability to achieve secure valve fixation without use of prosthetic material.  相似文献   
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Careful examination of the characteristics of both organisms revealed that we are dealing with Streptomyces violaceochromogenes and Streptomyces glaucescens. Calcium chloride decreased the permeability of both organisms as indicated by the low total nitrogen content of their media compared to the controls. Small doses of calcium nitrate suppressed the permeability of S. violaceochromogenes and increased that of S. glaucescens whereas the larger doses were stimulatory for both organisms. Calcium nitrate had similar effects on S. violaceochromogenes only without affecting S. glaucescens. The stimulatory effects of calcium gradually faded with increased concentration. Calcium chloride increased the proteolytic activity in S. violaceochromogenes media; a phenomenon that was apparent in S. glaucescens media only in the case of the larger doses. Calcium nitrate suppressed the proteolytic activity in S. glaucescens media. The cellulolytic activity of both organisms was suppressed by calcium but amylases were initiated in S. glaucescens media. Those of S. violaceochromogenes were arrested with the lower levels of calcium but the larger doses restored or stimulated their activity.  相似文献   
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The interaction of highly purified recombinant human tumor necrosis factor-alpha (rTNF-alpha) with human polymorphonuclear neutrophils (PMNs) was investigated. Binding of 125I-rTNF-alpha to PMN reached maximum levels in 30 min at 37 degrees C and in 2 h at 4 degrees C. Scatchard analysis of competitive binding data indicated approximately 6000 receptor sites per cell and a Kd of 1.37 nM. Binding data at 37 degrees C indicated a rapid internalization of rTNF-alpha. Following this receptor-mediated interaction, recombinant TNF-alpha was found to inhibit the migration of PMNs under agarose and to enhance PMN production of superoxide anion (O-2) in a dose-dependent manner. Furthermore, rTNF-alpha-activated PMNs caused a marked disruption of human umbilical-vein-derived endothelial cell monolayers and caused inhibition of their proliferative activities. These data substantiate the role of TNF-alpha as an activator of PMN functions and indicate that PMN/TNF-alpha/endothelial cell interactions may play a major role in inflammatory reactions.  相似文献   
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Although the transmission of coxsackievirus B3 occurs mainly via the oral route, little is known about the primary replication and persistence of this agent in the intestine. To address this question, BALB/c mice were inoculated by gavage with coxsackievirus B3, Nancy strain. The mice were killed from 1 hr to 90 days after infection. The viral markers were detected in the small intestine using RT-PCR, cell culture and detection of VP1 protein. Coxsackievirus B3 was detected positive by the three methods from hr 2 to day 45 after infection. By using monoclonal antibodies directed towards VP1, CD40 and CD26, the virus was shown to be present in the lymphocytes of the mucosa as soon as 2 hr after infection; in contrast, no virus was detected in the epithelial cells lining the intestinal lumen. Further experiments were performed to evaluate the capacity of coxsackievirus B3 to establish a persistent infection in two intestinal cell lines. In contrast to HT29 cells, the CaCo-2 cells were shown to develop a persistent infection for up to 20 passages, as demonstrated by the detection of viral RNA and VP1 protein. This study provides further evidence that, after infection by the oral route, the viral particles are concentrated in the lymphocytes of the mucosal layer. In addition, the results suggest that coxsackievirus B3 is capable of establishing a persistent infection in the small intestine that may act as a reservoir of viral particles for the delayed spread of the virus to other target organs.  相似文献   
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