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91.
Objective Successful resection of complex tumors involving the skull base (SB) depends on the ability to reconstruct the resulting defects. The objective of this study was to assess the outcomes of patients undergoing reconstruction after resection of SB tumors with free flaps.Methods From 1995 to 2010 a retrospective review of cases was undertaken. Demographics, histology, surgical management, complications, locoregional control, and survival were analyzed.Results We performed 62 flaps in 57 patients. There was a preponderance of sinonasal malignancies (45%), and most lesions involved the anterior SB (81%). A total of 94% of patients underwent radiotherapy. Reconstruction was undertaken mainly with anterolateral thigh (37%) or radial forearm (34%) flaps. Complications occurred in 17% of patients, and the flap''s success rate was 94%.Conclusion Free flaps are versatile and highly reliable for reconstructing defects resulting from resections of the SB. They should be considered for SB reconstruction of large three-dimensional defects as well as defects involving an irradiated field. Successful reconstruction of the SB can be performed using a small number of highly dependable flaps.  相似文献   
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93.

Background

Bariatric surgery (BS) is widely accepted for the treatment of patients with morbid obesity (MO). We aimed to determine presurgical predictors of and surgical technique-related differences in excess weight loss (EWL) 1?year after BS.

Methods

This retrospective study included 407 subjects (F/M 3:1, median age?=?44?years) who underwent laparoscopic Roux-en-Y gastric bypass (RYGB, n?=?307) or sleeve gastrectomy (SG, n?=?100) at our University Hospital and were evaluated 1?year after surgery.

Results

Baseline median (min–max) body mass index (BMI) was 47?kg/m2 (range?=?36–71). BMI was higher in the SG than in the RYGB group (53 vs. 46?kg/m2, p?p?p?=?0.2), was lower in diabetic than in nondiabetic subjects (71?±?17% vs. 79?±?17%, p?p?p?=?0.4) after taking into account baseline BMI. Multiple regression and logistic analysis showed that younger individuals with lower BMI but higher WC, and lower HbA1c and TG, had higher EWL and a higher rate of successful (EWL?≥?60%) weight loss.

Conclusions

Our data indicate that some of the characteristics that would have subjects referred early for BS were associated with higher weight loss. Therefore, the timing of laparoscopic BS might be an important factor for MO individuals in which medical weight loss intervention has failed.  相似文献   
94.
The ability of human complement regulatory molecules to prevent xenograft rejection following pig-to-primate xenotransplantation is limited. We assayed the efficacy of transgenic human decay accelerating factor (hDAF) expressed on porcine cells to inhibit the in vitro complement activity of primate sera. We measured the cytotoxic activity of baboon or human sera against peripheral blood lymphocytes (PBLs) from hDAF or nontransgenic pigs using a flow cytometry complement-mediated cytotoxicity assay (FCCA). We also analyzed the anti-Galalpha1-3Gal (alphaGal) antibody titer of the baboon sera by ELISA and the expression of hDAF and alphaGal on the PBL surface by immunofluorescence. Transgenic hDAF expression was capable of protecting pig cells against injury produced by both baboon and human serum. However, the hDAF molecule was more efficient against human than baboon sera. The humoral cytotoxicity capacity correlated with the level of both IgG and IgM anti-alphaGal antibodies. In addition, inhibition of complement-mediated cytotoxicity of hDAF pig cells correlated with the expression of hDAF and alphaGal molecules on target cells. These results confirm in vitro the protective role of hDAF in pig cells to heterologus complement mediated damage, but they also suggest that protection decreases in the presence of high levels of anti-porcine antibodies in serum, low expression of hDAF, or high expression of alphaGal on pig cells.  相似文献   
95.
96.
This study was to determine the efficacy of recombinant human bone morphogenetic protien‐2 (rhBMP‐2)/calcium phosphate matrix (CPX) paste to accelerate healing in a canine articular fracture model with associated subchondral defect. rhBMP‐2/CPX (BMP), CPX alone (CPX) or autogenous bone graft (ABG) was administered to a canine articular tibial plateau osteotomy with a subchondral defect in each of 21 female dogs. The unoperated contralateral limbs served as controls. Ground reaction forces, synovial fluid, radiographic changes, mechanical testing, bone density, and histology of bone and synovium were analyzed at 6 weeks after surgery. Radiographic analysis demonstrated that the BMP and CPX groups showed improved bony healing compared to the ABG group at week 6. Histomorphometric analysis demonstrated that the BMP group had significantly increased trabecular bone volume compared to the CPX and ABG groups. Mechanical testing revealed that the BMP group had significantly greater maximum failure loads than the ABG group. Histological analysis demonstrated that the BMP group had significantly less sub‐synovial inflammation than CPX group. This study demonstrated that rhBMP‐2/CPX accelerated healing of articular fractures with subchondral defect compared to ABG in most of the parameters evaluated, and had less subsynovial inflammation than the CPX alone in a canine model. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 466–471, 2009  相似文献   
97.
It is currently very rare to find mammary involvement in cases of tuberculosis, in either primary or secondary form. Diagnosis is classically clinical and microbiological, and the basic techniques used in imaging diagnosis are mammography and ultrasound. Computed tomography may define the involvement of the thoracic wall in those cases which present as mammary masses adhering to deep levels, and is also able to evaluate accompanying pulmonary disease, if it is present. Traditionally, treatment has consisted of quadrantectomy and specific antibiotic therapy. We present a case of tuberculous mammary abscess secondary to pulmonary disease, which was treated by percutaneous drainage controlled by CT and specific antibiotic therapy. We revise the diagnosis, differential diagnosis and treatment of mammary tuberculosis. Received: 27 July 1998; Revision received: 2 February 1999; Accepted: 20 April 1999  相似文献   
98.
BACKGROUND: To assess the incidence of and risk factors for Acute Stress Disorder (ASD) in children with injuries. Numerous studies have documented the increased incidence of PTSD in those initially diagnosed with ASD. PTSD symptoms cause tremendous morbidity and may persist for many years in some children. METHODS: Children hospitalized with one or more injuries were interviewed and assessed with the following: Child Stress Disorders Checklist (CSDC), Family Strains Scale, Brief Symptom Inventory (BSI) and Facial Pain Scale. RESULTS: Participants included sixty-five children (ages 7-18 years). The mechanisms of injury varied (e.g. MVC, penetrating). The mean injury severity score was 8.9 +/- 7. The mean length of hospital stay was 4.6 +/- 4.6 days. Altogether, 18 (27.7%) of participants met DSM IV criteria for ASD during their acute hospital stay. Risk factors such as level of family stress, caregiver stress, child's experience of pain, and child's age were predictive of acute stress symptoms. CONCLUSION: We have identified four risk factors of ASD that have implications for the treatment, and possibly, preventative intervention for PTSD. Further investigation and greater understanding of risk factors for ASD in children with injuries may facilitate the design of acute interventions to prevent the long-term negative outcomes of traumatic events.  相似文献   
99.
The majority of renal angiomyolipoma (AML) is sporadic and occasionally it occurs as part of tuberous sclerosis complex (TSC). Epithelioid AML (EAML), an uncommon variant, is considered potentially malignant based on anecdotal case reports. The prognostic significance of epithelioid component in an otherwise typical AML is uncertain. We studied 194 AMLs for the clinicopathologic features of epithelioid and TSC-associated AMLs. Epithelioid component was present in 15 cases (7.7%) with an average amount of 51% (range: 10% to 100%). Histologically, the epithelioid tumor cells were categorized into small, intermediate, and large cell type based on the cell size. Worrisome histologic features were seen in many EAMLs, including coagulative tumor necrosis in 27% (4/15), nuclear atypia in 93% (14/15), mitosis in 47% (7/15), and atypical mitosis in 1 case. All 15 EAML patients had a mean follow-up time of 5.1 years and none had local recurrence or distant metastasis. Sixteen (8.2%) AMLs occurred in patients with definitive TSC. Three histologic features, namely microscopic AML foci, epithelioid component, and epithelial cysts, were present in 10 (62.5%), 4 (25%), and 44% (7/16), respectively, of TSC-associated AMLs, compared with 11 (6.2%), 11 (6.2%), and 6 (3.4%), respectively, in non-TSC-associated AMLs (P value all <0.01). In summary, all 15 cases of EAMLs in our study had benign clinical outcomes despite adverse pathologic features. Epithelioid component, epithelial cysts, and microscopic AML foci are strongly associated with TSC and the presence of all 3 features should raise strong suspicion for TSC.  相似文献   
100.
Advances in technology, with the availability of optics and minitelevision cameras and improved endoscopic instrumentation (especially endo-stapler devices), have allowed the surgeon to obtain a superior panoramic view of the thoracic cavity and an optimal surgical manuvrability. This has determined the development, besides the traditional thoracotomic approach, of minimally invasive techniques of video-assisted thoracic surgery (VATS). An auxiliary mini-thoracotomic approach and the magnification of the operating theatre, which allows the surgeon to accomplish difficult manoeuvres under diret view, have progressively extended the indications of this procedure: at first used for the treatment of pneumothorax and pleural effusions, it is now employed in biopsy or atypical resection of pulmonary nodules, lung cancer staging and diagnostic-therapeutical procedures of mediastinal diseases, major pulmonary resections (lobectomy and pneumonectomy) and lung volume reduction surgery for emphysema (LVRS). The Authors review minimally invasive techniques of video-assisted thoracic surgery (VATS), compared to the traditional surgical ones, for the treatment of various thoracic diseases.  相似文献   
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