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51.
The intraoperative blood loss of 40 uncomplicated primary total hip arthroplasties was studied in a retrospective, matched pair analysis. Half of them were implanted in the supine position after complete excision of the capsule and the other half in the lateral position with preservation of the capsule. The patients were matched for mono- or bilateral procedure. Only one surgeon carried out the operations using the same operative technique and identical prosthesis in both groups. The intraoperative blood loss associated with the lateral position and preservation of the capsule averaged 830 ml and was significantly lower (P = 0.01) than 1165 ml with the supine position and complete capsulectomy. Thus, the intraoperative blood loss can be significantly reduced in primary total hip arthroplasty by choosing the lateral position and preserving the capsule.  相似文献   
52.
In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed.  相似文献   
53.
The overexpression of somatostatin receptors (SST-Rs) on various tumour cells provides the molecular basis for the successful use of radiolabelled SST analogues in clinical oncology. The objective of the study was to evaluate the tumour binding of In-1,4,7,10-tetraazacyclo-dodecane-N,N',N',N'-tetraacetic acid-lanreotide (In-DOTA-LAN) and In-DOTA-tyrosine-octreotide (In-DOTA-Tyr-OCT) in patients with stage IV melanoma. In addition, we evaluated the potential antiproliferative effect of SST analogues, together with an assessment of the functionality of SST-Rs, on four melanoma cell lines. Twenty-three patients with advanced metastatic melanoma underwent scintigraphy. Thirty-eight of 61 lesions (62%) were positively imaged with In-DOTA-LAN, whereas 23 (37%) were negative. With In-DOTA-Tyr-OCT, 10 of the 23 documented lesions (43%) were positive and 13 (56%) were negative. In vitro, cell lines showed no growth inhibition in the presence of SST analogues and no influence on cell cycle distribution was found with the addition of SST analogues to cultured cells. In addition, no functional surface SST-Rs could be demonstrated on these cell lines. Taken together, our results demonstrate the visualization of metastatic melanoma in a high percentage of patients, probably due to binding of SST analogues to SST-Rs on tumour vessels or infiltrating immune cells. Judging from our data, however, there is no evidence of functional SST-R expression on melanoma cells.  相似文献   
54.
OBJECTIVE: Pulmonary vein isolation is curative in selected patients with atrial fibrillation. The objective of this study was to assess the feasibility and safety (midterm results) of video-assisted thoracoscopic epicardial pulmonary vein isolation. METHODS: Twenty-seven patients (22 male patients) with atrial fibrillation (18 paroxysmal, 4 persistent, and 5 permanent; average age, 57 years) underwent bilateral video-assisted thoracoscopic off-pump epicardial pulmonary vein isolation and exclusion of the left atrial appendage. All patients had had unsuccessful drug therapy or were intolerant to antiarrhythmic drug therapy or were intolerant to warfarin. The approach included two 10-mm ports and one 5-cm working port (non-rib spreading) bilaterally. Pulmonary vein isolation was achieved bilaterally by using a bipolar radiofrequency device. The left atrial appendage was excised with a surgical stapler. RESULTS: Bilateral pulmonary vein isolation and left atrial appendage excision was performed successfully in all patients. There were no conversions to sternotomy or thoracotomy. All patients were extubated in the operating room. Postoperative complications in 3 patients were minor and resolved within 48 hours. One morbidly obese patient had more serious complications related to comorbid conditions. Average postoperative follow-up is approximately 6 months (173.6 days). Twenty-three patients have been followed up for greater than 3 months, and 21 of these patients are free of atrial fibrillation (91.3%). The results of magnetic resonance angiography were normal (no pulmonary vein stenosis) in 12 of 12 patients evaluated 3 to 6 months postoperatively. CONCLUSIONS: Bilateral video-assisted thoracoscopic pulmonary vein isolation with excision of the left atrial appendage is feasible and safe and offers a promising, new, minimally invasive, beating-heart approach for curative surgical treatment of atrial fibrillation.  相似文献   
55.
56.
Epstein-Barr virus-transformed human B cells (EBV-B cells), but not resting B cells or B cells activated by T cell-derived factors, have been shown to support the proliferation of tetanus toxoid (TT)-specific autologous T cell clones in response to TT antigen. The accessory cell function of EBV-B cells was compared to that of monocytes with regard to antigen uptake and processing. After an 18-h incubation period with 125I-labeled TT, the amount of radioactivity associated with the cells (approximately 50 ng/10(7) cells) and the percentage of cells containing radiolabeled material (approximately 50%) were equivalent for EBV-B cells and monocytes. Like with monocytes, EBV-B cells pulsed with TT for 18 h or more were equivalent in their capacity to induce T cell proliferation to EBV-B cells to which soluble TT was added for the duration of the culture period. The requirements for antigen uptake and presentation to T cells were similar for both EBV-B cells and monocytes. Both processes were energy dependent, inhibited by cold (4 degrees C), 2-deoxyglucose, and azide, and both required no de novo protein synthesis as they were not affected by pretreatment of the cells with the irreversible protein inhibitor pactamycin . Trypsin treatment of antigen-pulsed EBV-B cells and monocytes followed by fixation for 1 min in 0.03% paraformaldehyde completely abolished the capacity of both cell types to induce T cell proliferation. In both EBV-B cells and monocytes, antigen presentation, but not antigen uptake, was inhibited by the addition of the lysosomotropic agent chloroquine during the antigen-pulse period suggesting that the mechanisms of antigen processing are similar for both cell types. Vacuoles positive for acid phosphatase with an electron microscopic structure similar to that of lysosomes were found in EBV-B cells but not in resting B cells or B cells activated by T cell-derived factors. The present observations indicate that EBV-B cells take up antigen and process it in a fashion similar to monocytes. The presence of lysosomes appears to correlate with the capacity of B cells to present antigen.  相似文献   
57.
58.
The lack of epidemiological data on the frequency and/or burden of organic acidurias (OA) and mitochondrial fatty acid transport and oxidation disorders (mtFATOD) is one reason for hesitation to expand newborn screening (NBS) by tandem mass spectrometry (MS-MS). From 1999 to 2000, the frequency of ten potentially treatable OA and mtFATOD was assessed by active nation-wide surveillance on cases presenting with clinical symptoms using the German Paediatric Surveillance Unit (ESPED) system. Case ascertainment was complemented by a second independent source: 3-monthly inquiries in the metabolic laboratories performing secondary selected screening for OA and mtFATOD. Frequency estimates for clinically symptomatic cases older than 7 days in a birth cohort of 844,575 conventionally screened children was compared to the frequency found in a cohort of 382,247 screened by MS-MS in Bavaria and Baden-Württemberg. The overall frequency of the ten conditions considered was 1:8,000 (95% CI 1:11,000–1:6,000) by MS-MS as compared to 1:23,000 (95% CI 1:36,000–1:17,000) in symptomatic cases presenting mainly with metabolic crisis. The contributions of medium-chain acyl-CoA dehydrogenase deficiency (MCADD), other mtFATOD and OA were 29, 4 and 13 among the 46 cases identified by MS-MS, and 19, 1 and 13 among the 33 clinically symptomatic cases, respectively. Acute metabolic crisis, with a lethal outcome in four patients, was reported for 22/33 clinically symptomatic cases. No clinically symptomatic cases were reported from cohorts with screened by MS-MS. Conclusion: ten potentially treatable organic acidurias and mitochondrial fatty acid transport and oxidations disorders were more common than phenylketonuria with organic acidurias accounting for 28% of the cases detected by newborn screening and 39% of the cases identified on high risk screening. These conditions were related to considerable morbidity and mortality. Considerations for their inclusion in expanded newborn screening programmes might be warranted.Abbreviations ESPED Erhebungseinheit für seltene pädiatrische Erkrankungen in Deutschland (German Paediatric Surveillance Unit) - MCADD medium-chain acyl-CoA dehydrogenase deficiency - MS-MS tandem mass spectrometry - mtFATOD mitochondrial fatty acid transport and oxidation disorders - NBS newborn screening - OA organic acidurias  相似文献   
59.

Background

Wound infection after median sternotomy for cardiac or thoracic surgery is a serious complication. A variety of treatment plans have been advocated, and there is lack of agreement regarding the best treatment method. We present our results in patients with mediastinitis who have been treated in a simple, consistent manner.

Methods

We reviewed our experience with 40 consecutive patients with mediastinitis who were treated between January 1995 and May 2003 with a single-stage treatment consisting of sternal and soft tissue debridement and wound closure over mediastinal tubes with continuous irrigation and drainage. Tubes were placed posterior to the sternum in all patients and were irrigated continuously for at least 7 days with antibiotic or antibacterial solution. Systemic antibiotics were selected based on culture and sensitivity data and were administered for 2 to 6 weeks.

Results

All patients with mediastinitis treated in this manner survived. Of the 40 patients, 38 achieved complete healing of the wound without further operative intervention or major complication. One patient had recurrent infection and required sternal resection and advancement of muscle flaps. One patient had a residual localized focus of chondritis and underwent limited resection of cartilage.

Conclusions

In this series of patients with postoperative mediastinitis, a simplified approach consisting of wound debridement, reclosure over drains, and anterior mediastinal irrigation has been an effective treatment. The results we have achieved suggest that this technique may be a suitable option for treating this condition.  相似文献   
60.
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