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61.
62.

Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.  相似文献   
63.
64.

Background  

Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.  相似文献   
65.
The objective of this study is to compare the effects of three different anesthetic combinations on the electroretinogram in the same animals under similar laboratory conditions. Thiopental–isoflurane (TI), medetomidine–ketamine (MK), and xylazine–ketamine (XK) were used on each of 12 healthy miniature schnauzer dogs (MS) with a period of at least 3 weeks in between subsequent anesthesia protocols, using the Dog Standard Protocol. The scotopic ERGs consisted of scotopic low stimulus strength (S) responses designated S1, S2, S3, S4, and S5, at 1, 5, 10, 15, and 20 min after dark adaptation, respectively, and scotopic standard stimulus strength (S-ST) responses. The photopic ERGs consisted of a photopic single flash (P) response and 31 Hz flicker (P-FL) responses. For S-ST (2.5 cd s/m2), the amplitude of the a-wave using TI was significantly lower than that using MK (adjusted P = 0.05) and XK (adjusted P = 0.03), and the implicit time of the a-wave was significantly shorter than that using MK (adjusted P = 0.04). For P (2.5 cd s/m2), the amplitude of the b-wave using XK was significantly higher than that using MK (adjusted P = 0.01). The implicit times of the b-wave using TI was significantly longer and shorter than that of MK for S1, S2 and P-FL and for S4 and S-ST, respectively, and than that of XK for S2 and P-FL and for S5 and S-ST, respectively. The results of the present study showed that TI affected both the amplitude and the implicit time of the a-wave for S-ST and the implicit time of the b-wave relatively more so than was the case when using XK or MK. Therefore, it appears that either XK or MK could be advantageous to use rather than TI for clinical studies.  相似文献   
66.
Conclusion  We would like to stress that we do not necessarily consider AC for SPECT MPI to be unfeasible or unworthy of scientific pursuit; indeed, a great deal of creative scientific effort has been poured into this area of investigation over the past 3 decades, and much of it has contributed to a better understanding of the physics, as well as the clinical aspects, of our field. However, the great variety of available AC hardware and software “flavors,” the historical pattern of commercial release of insufficiently validated AC implementations, and the increasingly clouded health care reimbursement horizon may have created an environment where the envisioned users of the technology have been desensitized and discouraged from expecting it to ever come to fruition in a standardized, validated, and costeffective form. It has been reported as recently as 2005 that the “entire base of SPECT cameras has only 5% of systems with attenuation correction.”8 Perhaps the reports of AC’s demise are exaggerated, but it certainly seems as if the people have spoken and, after readying themselves for the wolf one too many times, have come to the conclusion that “the future (of AC) ain’t what it used to be” . . .at least not yet.  相似文献   
67.
Survival after resection of colorectal liver metastases has traditionally been associated with clinicopathologic factors. We sought to investigate whether echogenicity of colorectal liver metastasis as assessed by intraoperative ultrasound (IOUS) was a prognostic factor after hepatic resection. Prospective data on tumor IOUS appearance were collected in 84 patients who underwent hepatic resection for colorectal liver metastasis. Images were digitally recorded, blindly reviewed, and scored for echogenicity (hypo-, iso-, or hyperechoic). The median tumor number was 1 and the median tumor size was 5.0 cm. At the time of surgery, the IOUS appearance of the colorectal liver metastases were hypoechoic in 35 (41.7%) patients, isoechoic in 37 (44.0%) patients, and hyperechoic in 12 (14.3%) patients. Traditional clinicopathologic prognostic factors were similarly distributed among the three echogenicity groups (all p > 0.05). Patients with a hypoechoic lesion had a significantly shorter median survival (30.2 months) compared with patients who had either an isoechoic (53.2 months) or hyperechoic (42.3 months) lesion (p = 0.005). The 5-year survival after hepatic resection of colorectal liver metastasis was also associated with the echogenic appearance of the lesion (hypoechoic 14.4 vs isoechoic 37.4 vs hyperechoic 46.2%) (p < 0.05). Intraoperative ultrasound echogenicity should be considered a prognostic factor after hepatic resection of metastatic colorectal cancer. This study was presented at the 47th annual meeting of The Society for Surgery of the Alimentary Tract, Los Angeles, CA, USA, 22 May 2006.  相似文献   
68.
Gastroesophageal reflux disease (GERD) is a common disease and can be successfully treated by laparoscopic fundoplication. This article describes the technique of laparoscopic surgery for GERD with a focus on operative pitfalls.  相似文献   
69.
Management of upper gastrointestinal bleeding because of erosion of vessels by esophageal cancer may be challenging. We present herein the angiographic images of a 49-year-old patient who was admitted with massive bleeding from a tumor-eroded inferior thyroid artery. Attempts to control the bleeding by means of flexible endoscopy and insertion of a Sengstaken–Blakemore tube had failed. The diagnosis was impressively demonstrated by multislice computed tomography with intravenous contrast in the arterial phase and multiplanar reconstructions (computed tomography angiography) and by digital subtraction angiography. The bleeding was successfully treated with superselective catheterization and coiling of the eroded vessel.  相似文献   
70.
Abstract Background: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term functional outcome is often disappointing. However, little is known about social implications particularly in the elderly. Methods: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function, radiological outcome and social implications were evaluated. Results: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70–93 years). Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25–80 months), 22 (29%) died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination. Median Constant-Murley score was 41 points (range 17–77 points). Long-term results concerning pain were satisfying. The Oxford shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash their whole body by themselves. Conclusion: Most patients managed their daily life independently despite poor shoulder function.  相似文献   
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