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991.

Background  

This retrospective study compares the results of primary gastric bypass (PGB) versus secondary gastric bypass (SGB) performed after gastroplasty.  相似文献   
992.
The aim of this study was to assess structural indices from high-resolution peripheral quantitative computed tomography (HR-pQCT) images of the human proximal femur along with areal bone mineral density (aBMD) and compare the relationship of these parameters to bone strength in vitro. Thirty-one human proximal femur specimens (8 men and 23 women, median age 74 years, range 50–89) were examined with HR-pQCT at four regions of interest (femoral head, neck, major and minor trochanter) with 82 μm and in a subgroup (n = 17) with 41 μm resolution. Separate analyses of cortical and trabecular geometry, volumetric BMD (vBMD), and microarchitectural parameters were obtained. In addition, aBMD by dual-energy X-ray absorptiometry (DXA) was performed at conventional hip regions and maximal compressive strength (MCS) was determined in a side-impact biomechanical test. Twelve cervical and 19 trochanteric fractures were confirmed. Geometry, vBMD, microarchitecture, and aBMD correlated significantly with MCS, with Spearman’s correlation coefficients up to 0.77, 0.89, 0.90, and 0.85 (P < 0.001), respectively. No differences in these correlations were found using 41 μm compared to 82 μm resolution. In multiple regression analysis of MCS, a combined model (age- and sex-adjusted) with aBMD and structural parameters significantly increased R 2 values (up to 0.90) compared to a model holding aBMD alone (R 2 up to 0.78) (P < 0.05). Structural parameters and aBMD are equally related to MCS, and both cortical and trabecular structural parameters obtained from HR-pQCT images hold information on bone strength complementary to that of aBMD.  相似文献   
993.
This biographical sketch on Thomas Callaway corresponds to the historic text, The Classic: A Dissertation Upon Dislocations and Fractures of the Clavicle and Shoulder-Joint (1849) available at DOI .  相似文献   
994.

Background  

Distal femoral osteotomies (DFO) can be used to correct deformities around the knee. Although osteotomies can be fixed with either internal or external fixation techniques, the advantages of one over the other are unclear.  相似文献   
995.

Background  

Postoperative infection is a potentially devastating complication after THA and TKA. In the early postoperative period, clinicians often find nonspecific indicators of infection. Although leukocytosis may be a sign of a developing infection in the early postoperative period, it may also be part of a normal surgical response.  相似文献   
996.
BACKGROUND: Recently, tissue-engineered chondrocyte transplantation has been tried to treat full-thickness cartilage defects. We developed an injectable type II collagen gel scaffold by chemically reacting type II collagen with polyethylene glycol crosslinker. This type II collagen was prepared from the nasal septa of cattle. In the present study, chondrocytes embedded in type II collagen gel were injected into rabbit full-thickness cartilage defects without a periosteal graft, and the feasibility for clinical application of the gel was evaluated. METHODS: Chondrocytes were isolated from 1-kg New Zealand white rabbits. A full-thickness articular cartilage defect (5 mm diameter, 4 mm depth) was created on the patellar groove of the femur of 16 male 3-kg New Zealand white rabbits. A type II collagen solution of mixed chondrocytes at a density of 1 x 10(7) cells/ml was injected and transplanted into the defect in the right knee. The controls were the defect only in the left knee. At 4, 8, 12, and 24 weeks after operation, four cases from each group were evaluated macroscopically and histologically. RESULTS: After injection into the cartilage defect, the gel bonded to the adjacent cartilage and bone within several minutes. Macroscopic examination revealed that the surface of the transplanted area was smooth and exhibited similar coloration and good integration with the surrounding cartilage at 12 and 24 weeks after transplantation. Histological examination at 8 weeks revealed favorable hyaline cartilage regeneration with good chondrocyte morphology. At 12 and 24 weeks, reparative cartilage remained rich in type II collagen. According to O'Driscoll histological scores, significant differences between the transplanted and control groups were apparent at 12 and 24 weeks. Immunohistochemical staining indicated sufficient type II collagen synthesis in regenerated cartilage 8 weeks after transplantation, and it was maintained until 24 weeks. CONCLUSIONS: These results indicate that type II collagen gel is suitable for injection into cartilage defects without any covering of a graft and offers a useful scaffold during chondrocyte transplantation.  相似文献   
997.
Li T  Wang L  Yu HH  Sun HC  Qin LX  Ye QH  Fan J  Tang ZY 《Surgery today》2008,38(6):529-535
PURPOSE: We report our experience of diagnosing and treating hepatic angiomyolipoma (HAML), a rare benign mesenchymal tumor. METHODS: We analyzed retrospectively the clinicopathologic, radiological, and operative data of 25 patients who underwent surgery for HAML at our institute between November 2001 and May 2006. RESULTS: Most patients (20/25) were asymptomatic and had normal liver function. Ultrasonography (US) showed a heterogeneous hyperechoic mass in 13 of 23 patients, precontrast computed tomography (CT) showed that all of 12 lesions scanned were hypodense, and magnetic resonance imaging (MRI) showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in most (5/6) lesions. Marked enhancement in the arterial phase was seen in 10 of 12 lesions on CT scans and in 6 of 6 lesions on MRI scans. All tumors were composed of varying proportions of smooth muscle, adipose tissue, and blood vessels, and showed positive immunohistochemical staining for HMB-45. All patients underwent partial hepatectomy and there was no evidence of recurrence after a median follow-up of 43 months. CONCLUSION: The radiological features of HAML vary according to its histological components. The definitive diagnosis of HAML is challenging and depends on the presence of HMB-45-positive myoid cells. Hepatic angiomyolipoma is treated effectively with surgery and the prognosis is good.  相似文献   
998.
Bone marrow stem cells for urologic tissue engineering   总被引:1,自引:0,他引:1  
OBJECTIVES: Experiments in rats and dogs have demonstrated the potential of bone marrow-derived mesenchymal stem cells (MSCs) for urinary tract tissue engineering. However, the small graft size in rats and a failure to identify the MSCs in engineered tissues made it difficult to assess the true potential of these cells. Our goals were to characterize MSCs from pigs, determine their ability to differentiate into smooth muscle cells (SMCs) and use them in an autologous augmentation cystoplasty. METHODS: MSCs were isolated from pigs and analyzed for common markers of MSCs by flow cytometry. SMC differentiation was determined by immunoblotting. MSCs were isolated, genetically labeled, expanded in vitro, seeded onto small intestinal submucosa (SIS) and used for autologous bladder augmentation. RESULTS: Porcine MSCs are morphologically and immunophenotypically similar to human MSCs. Culturing MSCs at low density enhances proliferation rates. MSCs consistently differentiate into mature SMCs in vitro when maintained at confluence. Labeled MSCs grew on SIS over one week in vitro and survived a 2-week implantation as an autologous bladder augment in vivo. Some label-positive cells with SMC morphology were detected, but most SMCs were negative. Notably, many cells with a urothelial morphology stained positively. CONCLUSIONS: Porcine MSCs have similar properties to MSCs from other species and consistently undergo differentiation into mature SMC in vitro under specific culture conditions. Labeled MSCs within SIS may assist tissue regeneration in augmentation cystoplasty but may not significantly incorporate into smooth muscle bundles.  相似文献   
999.
The development of bone in immature rats and in aged rats has not been thoroughly studied. Therefore, we investigated the development of bones in young, middle-aged, and aged female rats. Because most rat chows contain soy proteins, including estrogenic isoflavones, as a source of protein, comparison of effects on mineral density and on areas of the cancellous and cortical parts of the metaphysis of the tibia as measured by quantitative computer tomography in animals fed with soy-free and soy-containing food was made. As surrogate parameters of bone metabolism serum, osteocalcin (OC) and the breakdown products of bone collagen--the Crosslaps--were also determined. The cancellous density increased between day 25 after birth to reach peak bone mass at 90 days of age; in 18-and 20-month-old animals, significant reduction was observed that was more profound in the animals fed with soy-free food. Serum OC and the Crosslaps were highest in 15-day-old and lowest in 9-, 18-, and 20-month-old animals. Animals fed with soy-containing food had significantly higher osteocalcin levels at day 15 and at 9 and 18 months of age. In the aged animals, intake of soy isoflavones that have an estrogenic effect appears to exert beneficial effects as these aged animals lost less cancellous bone, as indicated by their surrogate parameters of metabolism in the serum. It is concluded that exorbitantly high bone turnover is present in immature and peripubertal rats. Raising and keeping female rats under soy-free or soy-containing conditions has marked effects on several bone parameters that are of particular relevance in aged animals.  相似文献   
1000.
The number of cases of coronary artery bypass grafting (CABG) reached more than 21 000 in Japan in 2002, and the operative mortality decreased to less than 1%, including emergency operations. The annual number of CABGs in Japan declined 17% after 2003 to 18 000 cases in 2005 owing to unrestricted percutaneous coronary intervention (PCI) with drug-eluting stents. However, CABG is the best treatment for multivessel coronary artery disease based on the comparative data of PCI versus CABG. There have been two trends in CABG during the last decade. One is the widespread use of off-pump (OP) CABG, and the other is multiple coronary artery revascularization. In 2004 and 2005, approximately 60% of all isolated CABG procedures in Japan were performed without cardiopulmonary bypass. In a study of long-term outcomes comparing PCI with drug-eluting stents versus CABG with only arterial grafts, the latter was carried out in 52% of total cases and in 66% of OPCAB cases. OPCAB with multiple arterial grafts has become the standard CABG in Japan.  相似文献   
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