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991.
To validate the adverse effects of subluxation of the femoral head in Legg-Calve-Perthes disease, the authors made an experimental model of Perthes disease with subluxation in growing rabbits by interrupting the epiphyseal artery (devascularization) and immobilizing the knee in extension (immobilization). Seventy-two rabbits, 4 to 5 weeks old, were divided into three groups: group A with both devascularization and immobilization (25 rabbits), group B with devascularization only (25 rabbits), and group C with immobilization only (22 rabbits). In each experimental group, four to six rabbits each were killed at 1, 2, 4, 8, and 12 weeks. After reviewing the serial radiographs and gross specimens, the authors found six radiologic and six macroscopic abnormalities. The incidence and the severity of deformity in group A rabbits were higher than that of groups B or C in terms of the overall incidence of deformities (P <0.001), head deformity scores (P <0.001), and the incidence of a total collapse of the capital femoral epiphysis. In conclusion, subluxation of the immature femoral head with avascular necrosis in rabbits increased femoral head deformities.  相似文献   
992.
MicroRNAs (miRNAs) are non-coding RNAs that regulate basic cellular processes and are associated with cancer characteristics. The aim of this review is to summarize the principles of miRNA biogenesis and function and to describe their contribution to tumor development, especially in uro-oncology. Therefore a PubMed search was conducted. Up to March 2009 approximately 4,500 miRNA-related articles were cited in this database. Studies of miRNA expression and functional analyses prove their impact in carcinogenesis and their potential as diagnostic or prognostic markers or as novel therapeutic targets. Only a few miRNA-related studies have been published in uro-oncology so far. Although tumor-specific miRNA expression has been shown for urological neoplasms, the contradicting data show that miRNA research is still in its infancy in this field. A systematic elucidation of characteristic miRNA abnormalities could decisively improve diagnostics as well as therapy of urological tumors.  相似文献   
993.

Background

The indications of repeat fine-needle aspiration (FNA) for thyroid nodules with benign results of the Bethesda system were investigated.

Methods

A total of 1,398 nodules were classified according to the Thyroid Imaging Reporting and Data System (TIRADS). TIRADS category 3 included nodules without solidity, hypoechogenicity or marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape on ultrasonography (US). Categories 4a, 4b, 4c, and 5 included nodules with one, two, three or four, or five suspicious US features, respectively. The malignancy risks, and odds ratio (OR) with 95 % confidence interval (CI) were calculated. Analyses were performed for all nodules, nodules >10 mm, and nodules ≤10 mm.

Results

Of 1.398 nodules, 43 (3.1 %) were malignanct. The malignancy risks of benign nodules with categories 3, 4a, and 4b were 0.7, 1.2, and 0.7 %, respectively, whereas those for nodules with categories 4c and 5 were 9.8 and 22.2 %, respectively. The ORs of nodules with categories 4c and 5 were 19.4 (95 % CI 5.0–76.2) and 50.6 (95 % CI 10.4–245.0), respectively. In nodules >10 mm, the malignancy risks of categories 4c and 5 were 2.7 and 20 %, respectively, and the ORs were 10.7 (95 % CI 1.2–93.7) and 236.1 (95 % CI 12.6–4426.4), respectively. In nodules ≤ 10 mm, the malignancy risks of categories 4c and 5 were 12.6 and 22.6 %, respectively, and the ORs were 10.1 (95 % CI 1.3–78.0) and 18.9 (95 % CI 2.1–168.9), respectively.

Conclusions

Repeat US-guided FNA should be considered in benign thyroid nodules with three or more suspicious US features regardless of size.  相似文献   
994.
A percutaneous fine-needle aspiration biopsy of metastatic tumor and/or retroperitoneal, pelvic, or abdominal lymph nodes was accomplished in 101 patients. A diagnosis of metastatic disease was confirmed by this method in 49 patients. In 26 patients, surgical excisional biopsy or exploratory laparotomy was avoided. An unknown pelvic mass causation was diagnosed in 3 patients. In 15 of 57 patients with localized bladder, prostate, or testis cancer, involvement of regional lymph nodes was confirmed by transabdominal fine-needle aspiration. All 57 transabdominal aspirations were performed without complications. The method is inexpensive, safe, and can have a high accuracy in diagnosing a local tumor spread or distant metastases.  相似文献   
995.

Background

Ileostomy closure is a minor procedure and is performed through a small peristomal incision. However, a hard adhesion increases the technical difficulty. A peritoneofascial suture (PFS) will reduce the adhesion layers of the abdominal wall. This study was performed to evaluate whether the PFS method may decrease the extent of adhesions between the bowel and the abdominal wall opening and facilitate ileostomy mobilization.

Methods

Forty-two patients (24 males and 18 females) with a mean age of 57?years (range?=?31–80?years) and who were undergoing ileostomy closure were enrolled. The PFS group and the conventional group had 18 and 24 patients, respectively. The intraoperative findings such as degree of adhesion, mobilization time, and associated bowel injury were analyzed.

Results

The thickness of the abdominal wall and the rectus abdominis was similar in both groups. The overall operation time was shorter in the PFS group than in the conventional group (50.9 vs. 80.4?min, respectively, p?=?0.001). The ileostomy mobilization time was also shorter in the PFS group than in the conventional group (18.9 vs. 44.7?min, respectively, p?p?=?0.013). Bowel injury during mobilization was more common in the conventional group than in the PFS group (50.0?% vs. 16.7?%, respectively, p?=?0.053).

Conclusions

The peritoneofascial suture method is a simple procedure, and it may facilitate ileostomy mobilization by decreasing adhesion layers. To confirm the technical advantage of this method a randomized study will be needed.  相似文献   
996.
BACKGROUND: This retrospective study determined whether extracorporeal esophagojejunostomy after laparoscopy-assisted total gastrectomy (LATG) for gastric cancer can be considered minimally invasive surgery, compared to the conventional open total gastrectomy (OTG). PATIENTS AND METHODS: This retrospective study involved 60 patients seen between January 2004 and July 2006. Twenty-seven patients underwent LATG, and 33 patients had OTG. The surgical procedure included the use of five ports with an upper vertical midline incision. In all patients, reconstruction was performed by using a Roux-en-Y esophagojejunostomy through the minilaparotomy site. In all cases, the jejunojejunostomy was performed extracorporeally as the conventional method. In OTG, a Roux-en-Y esophagojejunostomy was performed with an upper midline incision. RESULTS: The mean number of retrieved lymph nodes was smaller and the mean operating time was longer in the LATG group. The postoperative hospital course was similar in both groups. In the LATG group, the mean length of the minilaparotomy incision was 8.0+/-1.2 cm (maximum length, 11 cm), and a direct relationship was observed between the distance from the xiphoid process to the esophageal hiatus (DisXE) and the minilaparotomy incision length (Spearman's correlation of rank coefficient: 0.386; P=0.046). CONCLUSIONS: With the concept of minimal invasiveness, if the patient's DisXE exceeds 9 cm, the length of the minilaparotomy incision in laparoscopic surgery could be disadvantageous. Nevertheless, we consider LATG the treatment of choice for early gastric cancer. If the patient's DisXE exceeds 9 cm, we consider intracorporeal anastomosis with the laparoscopic total gastrectomy. The type of esophagojejunostomy may be determined preoperatively by using three-dimensional abdominal computed tomography.  相似文献   
997.

Background

The purpose of the present study was to evaluate the clinicopathologic factors and ultrasound (US) features predictive of central lymph node metastasis (LNM) in patients diagnosed with papillary thyroid microcarcinoma (PTMC).

Methods

From March 2008 to August 2008, the clinicopathologic features and preoperative US features of 483 patients who were diagnosed with conventional PTMC were included. Medical records, US features, and pathology reports of all patients were retrospectively reviewed. Univariate and multivariate analysis was performed to identify clinicopathological prognostic factors associated with central LNM. Odds ratios (OR) with relative 95 % confidence intervals (95 % CI) were calculated to determine the relevance of all potential predictors of central LNM.

Results

Among the 483 patients with PTMC, 139 (28.8 %) patients had central LNM. The OR of significant independent factors were 2.055 (95 % CI, 1.137–3.716), 2.075 (95 % CI, 1.27–3.39), 1.71 (95 % CI, 1.073–2.724), and 15.897 (95 % CI, 4.173–60.569), respectively, for bilaterality, larger tumor size (>5 mm), extracapsular invasion, and lateral LNM. No significant association was seen among the US features of PTMC with central LNM.

Conclusions

Central lymph node metastasis in patients with PTMC was significantly associated with various clinicopathological factors, including larger tumor size (>5 mm), bilaterality, extracapsular invasion, and lateral LNM. When these features are detected on preoperative US, selective central compartment dissection may be helpful in patients diagnosed with PTMC.  相似文献   
998.

Purpose

To evaluate the interobserver and intermethod correlations of histogram metrics of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters acquired by multiple readers using the single-section and whole-tumor volume methods.

Materials and methods

Four DCE parameters (Ktrans, Kep, Ve , Vp) were evaluated in 45 patients (31 men and 14 women; mean age, 61 ± 11 years [range, 29–83 years]) with locally advanced rectal cancer using pre-chemoradiotherapy (CRT) MRI. Ten histogram metrics were extracted using two methods of lesion selection performed by three radiologists: the whole-tumor volume method for the whole tumor on axial section-by-section images and the single-section method for the entire area of the tumor on one axial image. The interobserver and intermethod correlations were evaluated using the intraclass correlation coefficients (ICCs).

Results

The ICCs showed excellent interobserver and intermethod correlations in most of histogram metrics of the DCE parameters. The ICCs among the three readers were > 0.7 (P < 0.001) for all histogram metrics, except for the minimum and maximum. The intermethod correlations for most of the histogram metrics were excellent for each radiologist, regardless of the differences in the radiologists’ experience.

Conclusion

The interobserver and intermethod correlations for most of the histogram metrics of the DCE parameters are excellent in rectal cancer. Therefore, the single-section method may be a potential alternative to the whole-tumor volume method using pre-CRT MRI, despite the fact that the high agreement between the two methods cannot be extrapolated to post-CRT MRI.  相似文献   
999.
Portal vein thrombosis (PVT) remains a challenging issue for liver transplantation surgeons. Most patients who have PVT undergo eversion thrombectomy. When thrombectomy is not successful due to diffuse PVT, other modalities are adapted, such as the use of a venous jump graft or portal tributaries. Here, we report our successful experience with reconstruction of portal flow using collateral plexus for a patient with grade 4 PVT. Thrombectomy did not restore portal flow. A pericholedochal plexus was found on the lateral wall of common bile duct. Direct end-to-end anastomosis was performed between the donor's portal vein and patient's choledochal plexus. Postoperative color Doppler ultrasound revealed normal portal flow.  相似文献   
1000.
BackgroundSecondary biliary cirrhosis (SBC) represents a unique form of cirrhosis that develops in the liver secondary to persistent biliary obstruction. This study aimed to review the living donor liver transplants (LDLTs) performed at our center for patients with SBC and end-stage liver disease and to share the perioperative strategies undertaken to achieve satisfactory outcomes.MethodsThe medical records of 29 patients who underwent LDLT for SBC between December 1994 and July 2018 at the Asan Medical Center (Seoul, South Korea) were retrospectively reviewed. Their clinical data were extracted and statistically analyzed. Survival curves were computed.ResultsThe perioperative and in-hospital morbidity rates were 72.4% and 10.3%, respectively. The overall mean recipient follow-up was 80.0 (SD, 66.4) months (range, 0.8-246.8 months). Patient survival rates after 1, 3, 5, and 10 years after transplant were 82.8%, 79.3%, 79.3%, and 79.3%, respectively. For liver grafts, the survival rates were 82.8%, 75.8%, 75.8%, and 75.8% at 1, 3, 5, and 10 years, respectively.ConclusionsLDLT is potentially a final lifesaving resort for patients with SBC with portal hypertension. However, considering the difficulty of surgery and perioperative management, LDLT should be performed by experienced transplant surgeons in a center where a multidisciplinary approach is possible.  相似文献   
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