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991.
Anomalous union of the pancreaticobiliary duct (AUPBD) is a congenital anomaly that is defined as a junction of the bile duct and pancreatic duct outside the duodenal wall. This anomaly results in a loss of normal sphincteric mechanisms at the pancreaticobiliary junction. As a result, regurgitation of pancreatic juice into the biliary system develops and causes choledochal cysts, choledocholithiasis, cholangitis, pancreatitis and malignancy of the biliary tract. Gallbladder cancer or common bile duct cancer associated with AUPBD and choledochal cysts have been frequently reported. But, intrahepatic cholangiocarcinoma associated with this condition has been only rarely reported. Here, we report a case of intrahepatic cholangiocarcinoma associated with AUPBD and choledochal cyst.  相似文献   
992.
993.
Catalytic methane steam reforming was conducted at low temperature using a Pd catalyst supported on Ce1−xMxO2 (x = 0 or 0.1, M = Ca, Ba, La, Y or Al) oxides with or without an electric field (EF). The effects of the catalyst support on catalytic activity and surface proton hopping were investigated. Results show that Pd/Al-CeO2 (Pd/Ce0.9Al0.1O2) showed higher activity than Pd/CeO2 with EF, although their activity was identical without EF. Thermogravimetry revealed a larger amount of H2O adsorbed onto Pd/Al-CeO2 than onto Pd/CeO2, so Al doping to CeO2 contributes to greater H2O adsorption. Furthermore, electrochemical conduction measurements of Pd/Al-CeO2 revealed a larger contribution of surface proton hopping than that for Pd/CeO2. This promotes the surface proton conductivity and catalytic activity during EF application.

Temperature dependence of electron/ion conductivity of Pd/CeO2 and Pd/Al-CeO2 under wet conditions with application of an electric field.  相似文献   
994.
The low-pressure spark plasma sintering (SPS) technique is adopted to fabricate hydroxyapatite–bioglass (HA–BG) scaffolds while maintaining the physical properties of both components, including their bulk and relative density and hardness. However, prior to their orthopaedic and dental applications, these scaffolds must be validated via pre-clinical assessments. In the present study, scaffolds with different ratios of HA : BG, namely, 100 : 0 (HB 0 S), 90 : 10 (HB 10 S), 80 : 20 (HB 20 S) and 70 : 30 (HB 30 S) were fabricated. These scaffolds were characterized by investigating their physicochemical properties (X-ray diffraction (XRD) and surface wettability), bioactivity in a simulated body fluid (SBF) (field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR) and calcium dissolution), antimicrobial properties, biocompatibility and osteoinduction of human bone marrow-derived mesenchymal stromal cells (hBMSCs) and human monocyte immune cell response. The XRD and surface wettability results confirmed no formation of undesirable phases and the enhanced surface hydrophilicity of the scaffolds, respectively. The bioactivity in SBF indicated the formation of bone-like apatite on the surface of the scaffolds, corresponding to an increase in BG%, which was confirmed through FTIR spectra and the increasing trend of calcium release in SBF. The scaffolds showed inhibition properties against Staphylococcus aureus and Staphylococcus epidermidis. The scanning electron microscopy (SEM) micrographs and Alamar Blue proliferation assay indicated the good attachment and significant proliferation, respectively, of hBMSCs on the scaffolds. Alizarin Red S staining confirmed that the scaffolds supported the mineralisation of hBMSCs. The osteogenic protein secretion (bone morphogenetic protein-2 (BMP2), type-I collagen (COL1) and osterix (OSX)) was significant on the HB 30 S-seeded hBMSCs when compared with that of HB 0 S. The monocyte migration was significantly halted in response to HA–BG-conditioned media when compared with the positive control (monocyte chemoattractant protein-1: MCP-1). In conclusion, the HB 30 S composite scaffold has a greater potential to substitute bone grafts in orthopaedic and dental applications.

HB 30 S composite scaffold inhibits Staphylococcus spp., supports the biocompatibility and osteogenic differentiation of hBMSCs and resists monocyte migration.  相似文献   
995.

Introduction

The purposes of this study were: (1) to compare tunnel locations using the conventional transtibial technique with reference data, and (2) to identify factors that make it difficult to position the femoral tunnel correctly or contribute to breakage of the bone bridge between the two tibial tunnels.

Materials and methods

A prospective study was performed on 28 patients who underwent double bundle ACL reconstruction. Locations of each tunnel were determined using an anatomic coordinate axes method (ACAM). Measurements included: thickness of the bone bridge between tibial two tunnels (BB), height from the union (HU) point to expected joint surface, the ratio between the length of Blumensaat’s line and the anterior–posterior length of the lateral femoral condyle (RBL), and the ratio between anterior–posterior and proximal–distal lengths of the medial wall of the lateral femoral condyle (RAPPD).

Results

The posterior–anterior direction of femoral AM tunnel, the proximal–distal direction of femoral PL tunnel, and the posterior–anterior direction of femoral PL tunnel were statistically significantly different from the reference data. In correlation analyses between BB or HU and other variables, the AM tibial tunnel and RBL showed a moderate negative correlation. The cutoff point for tunnel breakage was an RLB of 1.14, meaning that the possibility of bone bridge breakage would increases for RBL values of >1.14.

Conclusions

It seems that conventional transtibial drilling technique used during double bundle ACL reconstruction does not reproduce correct tunnel locations compared with reference data. This problem was found to be related to the bony geometry of the medial wall of the lateral femoral condyle or the bone bridge between the two tibial tunnels. Our results indicate that RBL should be determined by pre-operative CT or plain lateral radiography, and that transtibial single bundle reconstruction or double bundle reconstruction using other methods should be attempted when the RBL exceeds 1.14.  相似文献   
996.

Purpose

The aims of the present study were to compare the biomechanical effects on the adjacent segments after mono-segmental floating fusion with posterior semi-rigid or rigid stabilization, and to evaluate the effect of the amount of fusion mass on the biomechanical differences.

Methods

A detailed, nonlinear L1–S1 finite element model had been developed and validated. Then five models were reconstructed by different fixation techniques on the L3–L4 level: rigid fixation with an interbody spacer (Ti + IS), rigid fixation with a large interbody spacer (Ti + IS_all), semi-rigid fixation with an interbody spacer (PEEK + IS), semi-rigid fixation with a large interbody spacer (PEEK + IS_all), and semi-rigid fixation only (PEEK). Analyses were conducted for the case of erect standing position, flexion, and extension motion.

Results

At L1–L2 and L2–L3, PEEK + IS demonstrated less inter-segmental rotation and nucleus pressure increments from the intact model compared with Ti + IS. The L4–L5 and L5–S1 levels showed slightly higher values with PEEK + IS, but these differences among the instrumented models were not significant. The motion difference based on the fusion mass at the adjacent levels was at most 3 %. All instrumentation cases generated a 55 % higher facet contact force at the lower adjacent level (L4–L5) compared to that of the intact model during 26° extension and the largest increment was detected at the upper adjacent level (L2–L3) in the Ti + IS. Instrumentation with Ti + IS markedly increased the stress in the intervertebral disk at the upper adjacent level, while the stress with PEEK + IS appeared largest at the lower adjacent level.

Conclusions

Posterior instrumentation with semi-rigid rods may lower the incidence of disk and facet degeneration in the upper adjacent segment compared to rigid rods. On the other hand, the possibility of facet degeneration will be similar for all instrumentation devices in the lower adjacent segment in the long-term. The stiffness difference between rigid and semi-rigid rods on the changes in the adjacent motion segments was more crucial than amount of fusion mass.  相似文献   
997.
Laparoscopic sleeve gastrectomy (LSG) is an effective procedure for treating morbid obesity, and the majority of female patients who received LSG were at childbearing age. Female patients, who successfully lost weight following LSG and became pregnant, need to be evaluated carefully. Information was gathered, through prospectively maintained database and phone interview, on women who underwent LSG from May 2003 to July 2011. A total of 136 women underwent LSG in this period. There were 13 (9.6 %) pregnancies in 12 patients after LSG. The age before surgery was 28.3?±?4.0. The mean weight and body mass index (BMI) before LSG were 95.3?±?9.4 kg and 35.1?±?3.5 kg/m2, respectively. The average time from LSG to the first live birth was 32.0?±?19.1 months. Mean BMI decreased significantly after LSG, from 35.1?±?3.5 to 24.9?±?2.3 kg/m2 at conception. The mean percentage of excess body mass index loss was 85.8?±?16.7 % at conception and 42.7?±?25.1 % at delivery. Gained weight during pregnancy was 15.1?±?5.2 kg. The mean gestational age and birth weight were 39.0?±?1.6 weeks and 3,229.0?±?505.9 g. In two cases (15.4 %), cesarean section was performed. No cases of pregnancy-induced hypertension and diabetes developed. Major congenital anomalies and neonatal deaths were not recorded. Larger study with longer follow-up is needed to evaluate the effect of LSG in pregnancies. However, these findings show that LSG seems to be a safe option for morbidly obese women in their reproductive period.  相似文献   
998.
Reconstruction of extensive abdominal wall defects is a challenge for reconstructive surgeons. In this report, a case of reconstruction of a large abdominal wall defect using an eccentric perforator‐based pedicled anterolateral thigh (ALT) flap is presented. A 30‐year‐old man presented with recurrent desmoid‐type fibromatosis in the abdominal wall. The recurrent tumor was radically excised, and the en bloc excision resulted in a full‐thickness, large abdominal wall defect (25 cm × 20 cm). An eccentric perforator‐based pedicled ALT flap, including wide fascial extension, was transferred to the abdominal defect; fascial portions were sutured to the remnant abdominal fascia. Plication of the fascia along the sutured portion was performed to relieve the skin tension between the flap and the marginal skin of the abdominal defect. Eight months after surgery, the reconstructed abdomen had an acceptable esthetic appearance without tumor recurrence or hernia. The use of an eccentric perforator‐based pedicled ALT flap may be an alternative method for the reconstruction of extensive abdominal wall defects. © 2013 Wiley Periodicals, Inc. Microsurgery 33:482–486, 2013.  相似文献   
999.
1000.
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