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31.
The study purposed to determine if a navigation in total knee arthroplasty (TKA) leads to accurate limb alignment and component position than the conventional technique as measured by full length standing radiographs and to evaluate the correlation between navigation and radiographic measurements. A total of 160 knees underwent navigation (n = 80) or conventional (n = 80) TKAs. The frontal femoral alignment was more accurate in navigation TKAs, whereas mechanical axis and frontal tibial alignment were similar in both techniques. Although the intraoperative navigation alignment showed no outliers, postoperative radiographic measure resulted as much as 20% of outliers, and there was no correlation between the two measurements. This lack of correlation and inherent limitations in measuring TKA alignment may bring to question if plain radiograph are useful to determine if alignment achieved by navigation is accurate.  相似文献   
32.
Jeong IG  Ro JY  Kim SC  You D  Song C  Hong JH  Ahn H  Kim CS 《BJU international》2011,108(1):38-43
Study Type – Therapy (case series)
Level of Evidence 4 What’s known on the subject? and What does the study add? Although extranodal extension in node‐positive patients may provide prognostic information in certain urological malignancies, contradictory results have been reported in node‐positive patients after radical cystectomy for bladder cancer. We examined whether extranodal extension could have an impact on the outcomes of node‐positive patients who underwent radical cystectomy for bladder cancer in a single large tertiary hospital. We have shown that the presence of extranodal extension was not an independent prognostic factor in node‐positive patients after radical cystectomy and pelvic lymphadenectomy for bladder cancer.

OBJECTIVE

? To examine whether extranodal extension (ENE) has an impact on the outcome of node‐positive patients who underwent radical cystectomy for bladder cancer.

PATIENTS AND METHODS

? Of 543 consecutive patients who underwent radical cystectomy for urothelial carcinoma of the bladder between 1990 and 2007, 112 patients with lymph node metastasis detected on histological examination were evaluated with regard to recurrence‐free survival (RFS) and disease‐specific survival (DSS) based on ENE status.

RESULTS

? The overall 5‐year RFS and DSS rates were 22.3% and 33.8%, respectively. ENE was observed in 41 (36.6%) of the 112 patients. ? The presence of ENE was associated with advanced pathological nodal status (P= 0.004), more positive lymph nodes (P= 0.006), and higher lymph node density (P < 0.001). ? The incidence of positive ENE increased with large positive lymph node diameter (P < 0.001). ? Multivariate analysis showed that lymph node density (hazard ratio (HR) = 2.39, 95% CI 1.09–5.24, P= 0.029; and HR = 3.13, 1.43–6.84, P= 0.004) and use of adjuvant chemotherapy (HR = 1.80, 1.02–3.20, P= 0.041; and HR = 2.07, 1.13–3.79, P= 0.018) were significant predictors of RFS and DSS, respectively. ? After adjustment for other prognostic factors, ENE was not significantly related to RFS (P= 0.825) and DSS (P= 0.961) by multivariate analysis.

CONCLUSIONS

? The presence of ENE was not an independent prognostic factor in node‐positive patients after radical cystectomy for bladder cancer. ? Additional prospective studies are needed to determine the independent prognostic role of ENE.  相似文献   
33.
BACKGROUND: The present study investigated the feasibility of a single-stage operation consisting of self-expandable metallic stent (SEMS) placement followed by laparoscopic surgery for obstructive left colorectal cancer. METHODS: From July 2002 to March 2007, 17 consecutive patients with primary obstructive left colorectal cancer underwent SEMS placement followed by laparoscopic surgery. Data were collected retrospectively regarding clinicopathological findings, SEMS placement, operative procedures, and perioperative outcomes. Technical success was defined as successful stent deployment across the obstructive lesion, and clinical success as the possibility of performing a single-stage operation without creating a stoma. RESULTS: In the laparoscopic group, the technical success rate was 100% (17/17) and there was no morbidity associated with SEMS placement. The median interval to laparoscopic surgery was 7 (range, 2-11) days, and the procedures included 11 anterior resections, 3 left hemicolectomies, 2 Hartmann's procedures, and 1 subtotal colectomy. All procedures were completed laparoscopically without conversion to open surgery. The median operating time was 178 (range, 93-377) minutes, and the median estimated blood loss was 100 (range, 50-400) ml with no cases requiring intraoperative transfusions. The clinical success rate was 82.4% (14/17), and there was no surgical morbidity other than two patients in whom chyloperitoneum and ileus were controlled by using conservative management. The median postoperative hospital stay was 9 (range, 7-49) days. CONCLUSIONS: A single-stage operation consisting of SEMS placement followed by laparoscopic surgery seems to be a feasible and safe treatment option for obstructive left colorectal cancer.  相似文献   
34.
Background The objectives of this study were to investigate the clinicopathological features of branch intraductal papillary mucinous neoplasm (IPMN) and to determine safe criteria for its observation. Most clinicians agree that surgical resection is required to treat main duct-type IPMN because of its high malignancy rate. However, no definite treatment guideline (with respect to surgery or observation) has been issued on the management of branch duct type IPMN. Methods We retrospectively reviewed the clinicopathological data of 138 patients who underwent operations for IPMN between 1993 and 2006 at five institutes in Korea. Results Of 138 patients (mean age, 60.6 years; 87 men, 51 women), 76 underwent pancreatoduodenectomy, 39 distal pancreatectomy, 4 total pancreatectomy, and 20 limited pancreatic resection. There were 112 benign cases: 47 adenoma, 63 borderline cases, and 26 malignant cases, with 9 of these being noninvasive and 17 invasive. By univariate analysis, tumor size and the presence of a mural nodule were identified as meaningful predictors of malignancy. By receiver operating characteristic curve analysis, a tumor size of >2 cm was found to be the most valuable predictor of malignancy. When cases were classified according to tumor size and the presence of a mural nodule, the malignancy rate for a tumor ≤2 cm without a mural nodule was 9.2%, for a tumor of ≤2 cm plus a mural nodule was 25%, and for other conditions such as tumor >2 cm, >25%. Conclusions Many branch duct IPMNs are malignant. Surgical treatment is recommended, except in cases that are strongly suspected to be benign or cases that present a high operative risk. Observation is only recommended in patients with a tumor size of ≤2 cm without a mural nodule.  相似文献   
35.
BACKGROUND: Carcinoma of the ampulla of Vater has a more favorable prognosis, compared to other malignant tumors of the periampullary region, because it usually presents with symptoms in the early stage. However, treatment by local resection only of the ampullary carcinoma remains controversial. The aim of this study was to evaluate the treatment results of the ampulla of Vater carcinoma according to different types of operation in low-risk-group patients. METHODS: We retrospectively reviewed the medical records of 17 low-risk-group patients among a total of 102 patients with ampulla of Vater carcinoma who had underwent curative surgery from 1992 to 2002. All specimens were critically reviewed by a single expert pathologist, and the relationship between surgical outcomes and operation type was assessed. RESULTS: The low-risk group was comprised of 10 men and 7 women with a median age of 57.8 years. Thirteen of 17 patients underwent a pancreaticoduodenectomy (PD) or a pylorus preserving pancreaticoduodenectomy (PPPD), while 4 patients underwent a transduodenal local resection (TDLR). The operation time was significantly shorter in the TDLR group, compared to the PD or PPPD groups. Among the 17 patients, there was only 1 case of recurrence in the inguinal area 33 months after the pancreaticoduodenectomy. CONCLUSIONS: Transduodenal local resection is a comparable mode of operation for low-risk-group patients with Ampulla of Vater carcinoma. In particular, it is essential to evaluate the invasion depth in preoperative endoscopic ultrasonography, cell differentiation in preoperative biopsy, and positivity of resection margin accurately by using frozen section during the operation.  相似文献   
36.
37.
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   
38.
To effectively suppress porcine endogenous retroviruses (PERV)s, RNAi technique was utilized. RNAi is the up‐to‐date skill for gene knockdown which simultaneously multitargets both gag and pol genes critical for replication of PERVs. Previously, two of the most effective siRNAs (gag2, pol2) were found to reduce the expression of PERVs. Concurrent treatment of these two siRNAs (gag2+pol2) showed knockdown efficiency of up to 88% compared to negative control. However, despite the high initial knockdown efficiency 48 h after transfection caused by siRNA, it may only be a transient effect of suppressing PERVs. The multitargeting vector was designed, containing both gag and pol genes and making use of POL II miR Expression Vector, which allowed for persistent and multiple targeting. This is the latest shRNA system technique expressing and targeting like miRNA. Through antibiotics resistance characteristics utilizing this vector, miRNA‐transfected PK15 cells (gag2‐pol2) were selected during 10 days. An 88.1% reduction in the level of mRNA expression was found. In addition, we performed RT‐activity analysis and fluorescence in situ hybridization assay, and it demonstrated the highest knockdown efficiency in multitargeting (gag2+pol2) miRNA group. Therefore, according to the results above, gene knockdown system (siRNA and shRNA) through multitargeting strategy could effectively inhibit PERVs.  相似文献   
39.

Purpose

To understand the long-term surgical outcomes and prognostic factors for the operative treatment of cervical myelopathy (CM) in patients with athetoid cerebral palsy (ACP).

Methods

We retrospectively reviewed 24 patients with ACP who underwent surgery for CM at our hospital between March 2002 and June 2008. All patients had more than 5 years follow-up. Anterior fusion (11 patients), posterior fusion (1 patient), or combined anterior and posterior (AP) fusion (7 patients) and C1-2 fusion (5 patients) surgeries were performed. Surgical outcomes (average follow-up 102 months), as assessed using modified JOA (mJOA) scores, the Neck Disability Index (NDI), and a visual analog scale (VAS) were compared between the preoperative and postoperative states.

Results

Preoperatvie cervical kyphosis decreased mJOA scores significantly. Long-term follow-up clinical outcomes demonstrated that 10 patients showed favorable (excellent and good) outcomes and 11 patients had non-favorable (fair and worse) outcomes. According to the mJOA scores, patients showed postoperative improvement (7.10–10.45). NDI decreased from 68.46 to 31.66. A second operation was done in seven cases due to instrument failure, progressive kyphotic deformities and adjacent segment degeneration. A preoperative botulinum toxin injection significantly decreased (p < 0.05) the incidence of a second operation.

Conclusions

Patients with ACP have high incidence of instrument failure. Strong surgical fixation, bone fusion and perioperative immobilizations using botulinum toxin injection should be carefully planned preoperatively.  相似文献   
40.
Implant arthroplasty and arthrodesis of the first metatarsophalangeal joint are the main surgical treatment options for advanced hallux rigidus. The superiority of each modality continues to be debated, because there are few high-quality evidence-based studies, such as randomized controlled clinical trials or meta-analyses of comparative studies. The purpose of this study was to identify whether implant arthroplasty or arthrodesis is superior for the treatment of advanced hallux rigidus through meta-analysis of comparative studies. A comprehensive search of the MEDLINE, EMBASE, and Cochrane library databases was conducted. Only retrospective or prospective comparative studies were included in this meta-analysis. The literature search, data extraction, and quality assessment were conducted by 2 independent reviewers. The primary outcomes were clinical scores and patient satisfaction. The rate of reoperation and complication were also investigated. Seven comparative studies were included (2 prospective and 5 retrospective studies). There were no significant differences between the 2 groups in the American Orthopedic Foot and Ankle Society-Hallux Metatarsophalangeal Interphalangeal score, patient satisfaction rate, reoperation rate, or complication rate. The visual analogue scale for pain was significantly lower in the arthrodesis group than the implant arthroplasty group. This meta-analysis revealed that implant arthroplasty and arthrodesis of the first metatarsophalangeal joint led to similar clinical outcomes, patient satisfaction, reoperation rates, and complication rates, whereas pain was significantly lower in arthrodesis. Further studies of high methodological quality are required to confirm these conclusions.  相似文献   
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