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81.
Sixty-seven patients (78 hips) who were younger than 50 years underwent cementless total hip arthroplasty using a porous-coated acetabular cup, an alumina liner, a 28-mm alumina head, and a proximally porous-coated femoral stem. One patient (1 hip) died and 2 patients (3 hips) were lost to follow-up. The remaining 64 patients (74 hips) were followed for 5 to 6 years. Their mean age at the index operation was 37 years. The mean Harris hip score was 94 points at the time of final follow-up. Four patients (4 hips) had mild thigh pain. All acetabular and femoral components were bone-ingrown, and neither pelvic nor femoral osteolysis was identified. No fracture of the ceramic liner or head was identified. Wear of the ceramic components was undetectable in 27 hips in which measurement was possible.  相似文献   
82.
Jeon DH  Oh K  Oh BC  Nam DH  Kim CH  Park HB  Cho J  Lee JR  Lee DS  Lee G 《Xenotransplantation》2007,14(3):236-242
BACKGROUND: Effective intervention achieved by manipulating cell-mediated xenogeneic immune responses would critically increase the clinical feasibility of xenotransplantation as immediate hyperacute rejections become controllable through genetic modulations of donor organs. Endogenous negative regulatory signals like the programmed death 1 (PD-1)-programmed death ligand 1 (PD-L1) system are candidate targets for the control of cell-mediated xenogeneic immune response. METHODS: A porcine PD-L1 molecule was cloned using RACE (rapid amplification of cDNA ends) technology based on the human PD-L1 sequence. The functional effects of cloned porcine PD-L1 were tested on human CD4(+) T cell activation using porcine PD-L1-transfected bystander cells. Cellular proliferation was monitored by [3H] thymidine incorporation, and human T cell apoptosis was measured by flow cytometry. RESULTS: Porcine PD-L1 (GenBank accession number AY837780) was found to have 73.8% sequence homology with human PD-L1 and to contain two immunoglobulin domains in its extracellular region. Moreover, porcine PD-L1 expressed on Chinese hamster ovary (CHO) cells inhibited human CD4(+) T cell proliferation stimulated with anti-CD3 only or anti-CD3 plus anti-CD28. Percentages of apoptotic activated human T cells increased by over 30% in the presence of porcine PD-L1/CHO cells, and the addition of recombinant human PD-1-Fc fusion proteins during human T cell activation reversed the inhibitory effects of porcine PD-L1. CONCLUSIONS: Cloned porcine PD-L1 showed high sequence homology with human PD-L1 and a similar molecular structure. Moreover, porcine PD-L1 inhibited human CD4(+) T cell activation in human PD-1-dependent manner, and this involved activated T cell apoptosis. The authors suggest that PD-1-PD-L1 might play an important endogenous immune regulatory role during xenogeneic transplantation, and that the effective application of this system would improve transplanted xenogeneic organ survival.  相似文献   
83.

Background

Using the da Vinci® robotic system, surgeons can complete secure thyroidectomy without noticeable neck scarring. This study compared the surgical completeness of transaxillary robotic thyroidectomy (RT) with conventional open procedures (OT) in treating papillary thyroid carcinoma (PTC) patients.

Materials and methods

From April 2009 through February 2011, 94 PTC patients underwent total thyroidectomy with central compartment neck dissection (CCND) at Yonsei University College of Medicine. All patients received 1.1 GBq radioactive iodine (RAI) ablation, post-therapy whole-body scans (TxWBS), and diagnostic WBS (DxWBS) 1 year later. We prospectively compared patient clinicopathologic characteristics and surgical completeness between the two groups.

Results

Fifty-one patients underwent OT and 43 underwent RT. Mean age was significantly younger in the RT group. Tumor size, capsular-invasion frequency, multifocality, bilaterality, and central nodal metastasis were not different between the two groups. The number of retrieved nodes during CCND did not significantly differ between the groups. There was no significant difference between the OT and RT groups in stimulated thyroglobulin levels acquired during TxWBS and DxWBS. The RAI uptake ratios at TxWBS were significantly higher in the RT group compared with the OT group; however, follow-up DxWBS showed no difference in RAI uptake ratios. Also, the ablation success rate was similar between the two groups. There were no abnormal findings in follow-up neck ultrasonography in either group.

Conclusion

Remnant thyroid tissue ablation after transaxillary RT was successfully managed by 1.1 GBq RAI. RT showed similar surgical completeness versus conventional OT, and provides a safe and feasible surgical option for PTC patients.  相似文献   
84.
Coracoid process fracture is an uncommon injury and can be easily missed. An associated acute subscapularis tear is still rare. Herein, we describe a 61 year old male who fell from a 2 meter height (stair case) and presented with isolated coracoid process fracture with acute subscapularis tear without dislocation of (R) shoulder joint. The plain x-rays, CT scan and MR arthrography comprised the diagnosis. He was operated upon with reattachment of subscapularis to lesser tuberosity and conjoint tendons to pectoralis major. At 6 mo followup he had good range of motion and his MRI revealed complete healing.  相似文献   
85.
Oncostatin M (OSM) is a multifunctional cytokine found in a variety of pathologic conditions, which leads to excessive collagen deposition. Current studies demonstrate that OSM is also a mitogen for fibroblasts and has an anti‐inflammatory action. It was therefore hypothesised that OSM may play an important role in healing of chronic wounds that usually involve decreased fibroblast function and persist in the inflammatory stage for a long time. In a previous in vitro study, the authors showed that OSM increased wound healing activities of diabetic dermal fibroblasts. However, wound healing in vivo is a complex process involving multiple factors. Thus, the purpose of this study was to evaluate the effect of OSM on diabetic wound healing in vivo. Five diabetic mice were used in this study. Four full‐thickness round wounds were created on the back of each mouse (total 20 wounds). OSM was applied on the two left‐side wounds (n = 10) and phosphate‐buffered saline was applied on the two right‐side wounds (n = 10). After 10 days, unhealed wound areas of the OSM and control groups were compared using the stereoimage optical topometer system. Also, epithelialisation, wound contraction and reduction in wound volume in each group were compared. The OSM‐treated group showed superior results in all of the tested parameters. In particular, the unhealed wound area and the reduction in wound volume demonstrated statistically significant differences (P < 0·05). The results of this study indicate that topical application of OSM may have the potential to accelerate healing of diabetic wounds.  相似文献   
86.
87.

Background

The purpose of this study is to report a modified transtibial technique to approach the center of anatomical femoral footprint in anterior cruciate ligament (ACL) reconstruction and to investigate the accurate femoral tunnel position with 3-dimensional computed tomography (3D-CT) and radiography after reconstruction.

Methods

From December 2010 to October 2011, we evaluated 98 patients who underwent primary ACL reconstruction using a modified transtibial technique to approach the center of anatomical femoral footprint in single bundle ACL reconstruction with hamstring autograft. Their femoral tunnel positions were investigated with 3D-CT and radiography postoperatively. Femoral tunnel angle was measured on the postoperative anteroposterior (AP) radiograph and the center of the femoral tunnel aperture on the lateral femoral condyle was assessed with 3D-CT according to the quadrant method by two orthopedic surgeons.

Results

According to the quadrant method with 3D-CT, the femoral tunnel was measured at a mean of 32.94% ± 5.16% from the proximal condylar surface (parallel to the Blumensaat line) and 41.89% ± 5.58% from the notch roof (perpendicular to the Blumensaat line) with good interobserver (intraclass correlation coefficients [ICC], 0.766 and 0.793, respectively) and intraobserver reliability (ICC, 0.875 and 0.893, respectively). According to the radiographic measurement on the AP view, the femoral tunnel angles averaged 50.43° ± 7.04° (ICC, 0.783 and 0.911, respectively).

Conclusions

Our modified transtibial technique is anticipated to provide more anatomical placement of the femoral tunnel during ACL reconstruction than the former traditional transtibial techniques.  相似文献   
88.
The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7), <0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (> or =7) had a 6.3 times higher mortality than those with a low SUV(max)(<7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (>10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors.  相似文献   
89.
Ham WS  Jeong HJ  Han SW  Kim JH  Kim DK 《The Journal of urology》2004,172(3):1108-1110
PURPOSE: Increasing clinical importance is being placed on the role of differential renal function (DRF) in the management of congenital ureteropelvic junction obstruction. Supranormal DRF of the hydronephrotic kidney on renal scan is a puzzling phenomenon and is hypothesized to be due to an increase in single nephron filtration or nephron volume without sound evidence. We studied the histopathological changes of hydronephrotic kidneys to determine whether glomerular hypertrophy underlies supranormal DRF. MATERIALS AND METHODS: We retrospectively evaluated the records of 3 females and 32 males with unilateral congenital hydronephrosis who underwent pyeloplasty. Mean patient age at operation was 12.6 months (range 0.1 to 144). Needle biopsies from 3 different sites at the lower pole of the kidney were performed during surgery. To evaluate the presence of glomerular hypertrophy, the maximal planar area of glomeruli was measured under light microscopy using an image analyzer. Tissue samples obtained from kidneys without a history of urinary tract disease at autopsy were used as controls. The mean glomerular areas of the patient and control groups were evaluated according to DRF and age. RESULTS: The mean glomerular area values of the patient group were smaller than those of the control group, except for 4 patients. The glomerular areas of the hydronephrotic kidneys with supranormal DRF were not significantly different from those of the control group. Instead, the probability of larger renal glomeruli increased with decreasing DRF (p = 0.1155). CONCLUSIONS: Increased nephron volume can be discounted as a cause of supranormal DRF.  相似文献   
90.

Background

Preoperative assessment of the nipple–areolar complex (NAC) is invaluable when considering nipple-sparing mastectomy. Our hypothesis is that breast magnetic resonance imaging (MRI) may predict involvement of the NAC with tumor.

Methods

Clinical, histopathologic, and imaging data were compiled for patients who underwent preoperative breast MRI followed by mastectomy or nipple-sparing mastectomy for malignancy between 2006 and 2009. Blinded rereview of all MRI studies was performed by a breast MRI imager and compared to initial MRI findings. Multivariate analysis identified variables predicting NAC involvement with tumor.

Results

Of 77 breasts, 18 (23 %) had tumor involving or within 1 cm of the NAC. The sensitivity of detecting histopathologically confirmed NAC involvement was 61 % with history and/or physical examination, and 56 % with MRI. Univariate analysis identified the following variables as significant for NAC involvement: large tumors near the nipple on preoperative MRI, node-positive disease, invasive lobular carcinoma, advanced histopathologic T stage, and neoadjuvant chemotherapy. On multivariate analysis, only tumor size >2 cm and distance from tumor edge to the NAC <2 cm on MRI maintained significance. Pearson correlation coefficient for MRI size compared to histopathologic size was 0.53 (P < 0.0001).

Conclusions

MRI is not superior to thorough clinical evaluation for predicting tumor in or near the NAC. However, MRI-measured tumor size and distance from the NAC are correlated with increased risk of NAC involvement. The combination of preoperative history and physical examination, tumor characteristics, and breast MRI can aid the surgeon in predicting a tumor-involved nipple more than any single modality alone.  相似文献   
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