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11.

Background  

Thoracic outlet syndrome is thought to be caused by compression of the brachial plexus or subclavian artery in the interscalene, costoclavicular, or subcoracoid space. Some provocative tests are widely used for diagnosing thoracic outlet syndrome. However, whether provocative positions actually compress the neurovascular bundle in these spaces remains unclear. The purpose of this study was to investigate the possibility of neurovascular bundle compression in the costoclavicular space by measuring the pressure applied to the brachial plexus and subclavian artery in provocative positions.  相似文献   
12.
Although an ascending aortic thrombus is a rare finding, it may cause major embolic complications. We report a case of a 58-year-old male who suffered from cerebral and left renal infarctions due to emboli from a giant thrombus in the ascending aorta. The thrombus was demonstrated by computed tomography and transesophageal echocardiography. Ten days after the initiation of anticoagulation therapy, surgery was performed. After a median sternotomy was performed and cardiopulmonary bypass was initiated, the ascending aorta was replaced with a synthetic graft under hypothermic circulatory arrest and retrograde cerebral perfusion. The excised specimen revealed a 3.5×3.0×3.0-cm pedunculated thrombus. The patient's postoperative recovery was uneventful, and there was no recurrence of aortic thrombosis during one year of postoperative follow-up. The patient had no coagulation disorders, and the etiology of this giant thrombus remains unclear. We believe that initial treatment for an ascending aortic thrombus should be emergency surgery before it leads to major embolic events. However, the treatment strategy for a thrombus causing cerebral infarction is sometimes difficult to develop.  相似文献   
13.
Human pluripotent embryonic stem cells (hESCs) have great promise for research into human developmental biology, development of cell therapies for the treatment of diseases, toxicology, and drug discovery. Traditionally, undifferentiated hESCs are maintained on mouse embryonic fibroblasts (MEFs), which impede the clinical applications of hESCs. Here we have examined the long-term stability of the Japanese hESC line (KhES-1) in feeder-free culture. KhES-1 cells were cultured with MEF conditioned medium (CM) and different doses of basic fibroblast growth factor (bFGF) in six-well-plates of which the surface was coated with Matrigel. KhES-1 cells were maintained for at least 40 passages. In this culture system, the cells maintained stable proliferation rates and steadily expressed Oct-4, Nanog, and alkaline phosphatase. In addition, KhES-1 cells maintained without direct feeder contact formed embryonic bodies with expression of markers from the three germ layers. Here we demonstrated that Japanese human embryonic stem cells KhES-1 were cultured long term in a feeder-free method, while retaining pluripotency in vitro.  相似文献   
14.
BACKGROUND: Although knowledge of cancer invasion of the portal bifurcation is vitally important in planning an operation for perihilar cholangiocarcinoma, the diagnostic capability of multidetector-row computed tomography (MDCT) for this purpose has not been assessed. We evaluated how well MDCT could identify cancer invasion of the portal bifurcation by perihilar cholangiocarcinoma. METHODS: Between April 2003 and June 2005, perihilar cholangiocarcinoma was resected in 87 patients, 83 of whom underwent MDCT within 1 month before the surgery. Three-dimensional volume-rendered (3DVR) and multiplanar reformation (MPR) images were examined for evidence of portal vein invasion. Agreement with intraoperative and pathologic findings was assessed. Portal bifurcation findings by 3DVR and MPR were classified into no portal vein stenosis, unilateral stenosis, or more extensive stenosis, and also into tumor contact with the bifurcation in no, one of two, or two projections. RESULTS: For macroscopic portal vein invasion, sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were 81.5, 91.1, 81.5, 91.1, and 88.0% in 3D portography and 96.3, 92.6, 86.7, 98.1, and 94.0% in MPR, respectively. Findings by both 3DVR and MPR were significantly correlated with depth of cancer invasion (p < 0.001). CONCLUSION: MDCT is useful in assessing cancer invasion of the portal vein bifurcation by perihilar cholangiocarcinoma.  相似文献   
15.
Airway scope (AWS) is a rigid indirect laryngoscope with integrated tube guidance and can improve laryngeal exposure compared to the conventional direct laryngoscope. It is expected that the clear and improved laryngeal view obtained with AWS can eliminate the risk of esophageal intubation. We, however, experienced 3 cases of esophageal intubation out of 600 clinical cases with AWS in 15 month after its market release. Two cases were by novice anesthesiologists with fewer than 10 intubation experiences with AWS. Although they had had more than 100 intubation experiences with Macintosh laryngoscope, they did not have sharp eye for incorrect intubation with AWS. The third case was performed by an experienced laryngoscopist but it was difficult to identify the glottic opening because patient had distracted airway anatomy due to laryngeal tumor. In all cases esophageal intubation was immediately noticed and airway was secured uneventfully. We conclude that intubation under vision with improved laryngeal view is still not sufficient to prevent esophageal intubation.  相似文献   
16.
We report a case of a 33-year old man who presented with symptoms and signs of an acute biliary tract obstruction with jaundice and abdominal pain. Diagnostic imaging studies revealed a biliary stricture of the hepatic confluence, and a mass at the hepatic hilum which obstructed the extrahepatic bile duct from the outside. At laparotomy, there was 3-cm-size nodule at the hilum which presented with a rubbery consistency. We performed extrahepatic bile duct resection and right and left hepaticojejunostomy. Histological examination of the resected specimen revealed follicular lymphoma, which consisted of medium cleaved follicle-like cells, grade 1 of 3 according to the revised European-American classification of lymphoid neoplasms proposed by International Lymphoma Study Group. Postoperative follow-up of more than 1 year has been completely uneventful, without any symptoms or signs of disease recurrence. This is the second case report of follicular lymphoma of the extrahepatic bile duct.  相似文献   
17.
OBJECTIVES: The purpose of this study was to determine the most suitable candidates for scalene lymph node biopsy to detect non-palpable scalene lymph node metastasis (N(3)-scalene) in non-small cell lung cancer patients. METHODS: Standard cervical mediastioscopies and ipsilateral scalene lymph node biopsies were performed preoperatively by a single surgeon on 121 consecutive patients with non-small cell lung cancer scheduled to have surgical resection between January 1997 and August 2002, who had neither evidence of distant metastasis on imaging diagnosis nor palpable supraclavicular lymph nodes. RESULTS: N(3)-scalene was detected in six patients (5.0%), who all had non-squamous cell carcinoma, including one (1.0%) out of 98 patients with negative standard cervical mediastinoscopy and five (21.7%) out of the remaining 23 patients with positive mediastinal lymph node involvement. There was a significant difference in the incidence of the N(3)-scalene between the two groups (P<0.01). Five patients with N(3)-scalene had metastatic lesions in the multilevel mediastinal lymph node station on the same side as the cancer (multilevel N(2)), and accounted for 31.3% of 16 patients with multilevel N(2) disease. The N(3)-scalene was detected in 5 (45.5%) of 11 patients with lung cancer classified as non-squamous cell carcinoma with multilevel N(2) disease. CONCLUSIONS: The results of the present study suggest that non-palpable scalene lymph node biopsy is indicated for lung cancer patients diagnosed as having non-squamous cell carcinoma with mediastinoscopic multilevel N(2) disease.  相似文献   
18.

Purpose

We report the outcome of intercalary resection of the femoral diaphysis and extracorporeal irradiated autologous bone graft reconstruction, without the use of vascularized fibular graft.

Methods

Six patients with Ewing sarcoma of the mid-shaft femur who were treated by limb sparing tumour resection and reconstruction with extracorporeal irradiated autologous bone graft with intramedullary cement between 2002 and 2010 were studied.

Results

Mean age at the time of surgery was ten years (range, four–23). The length of resected femoral bone averaged 23 cm (15–32 cm). The ratio of bone resection length to total femoral length averaged 60 % (56–66 %). The patients had been followed up for between 16 and 79 months (mean, 41 months) at the time of the study. There was no infection nor fracture in this series. Primary union of the distal and proximal osteotomy sites was achieved in three patients. Delayed union of the proximal osteotomy site occurred in one patient that was successfully treated with iliac crest bone grafting. One patient developed non-union at the distal osteotomy site which failed to heal with bone grafting and was therefore converted to endoprosthetic replacement, and another patient was converted to rotationplasty at five months post-surgery because of contaminated margins. Function was excellent in all patients with surviving re-implanted bone. Local recurrence arose in one patient.

Conclusion

Our experience suggests that cement augmentation of extracorporeal irradiated and re-implanted bone autografts offer a useful method of reconstructing large femoral diaphyseal bone defects after excision of primary malignant bone tumours.  相似文献   
19.
OBJECTIVE: To better determine the role of portal vein resection and its effect on survival, as well as to appreciate the impact of portal vein invasion on prognosis in hilar cholangiocarcinoma. SUMMARY BACKGROUND DATA: Hepatectomy with portal vein resection is sometimes performed for locally advanced hilar cholangiocarcinoma. However, the significance of microscopic invasion of the portal vein has not been determined. METHODS: Medical records of 160 patients with hilar cholangiocarcinoma who underwent macroscopically curative hepatectomy with (n = 52) or without portal vein resection (n = 108) were reviewed. Invasion of the portal vein was assessed histologically on the surgical specimen, and results were correlated with clinicopathologic features and survival. RESULTS: Surgical mortality, including all hospital deaths, was similar in patients who did and did not undergo portal vein resection (9.6% vs. 9.3%), but the primary tumor was more advanced in patients who underwent portal vein resection. Histologically, no invasion was found in 16 (30.8%) of resected portal veins. However, dense fibrosis adjacent to the portal vein was common, and the mean distance between the leading edge of cancer cells and the adventitia of the portal vein was 437 +/- 431 mum. The prognosis was worse in patients with than without portal vein resection (5-year survival, 9.9% vs. 36.8%; P < 0.0001). The presence or absence of microscopic invasion of the resected portal vein did not influence survival (16.6 months in patients with microscopic invasion vs. 19.4 months in those without; P = 0.1506). Multivariate analysis identified histologic differentiation, lymph node metastasis, and macroscopic portal vein invasion as independent prognostic factors. CONCLUSIONS: Microscopic invasion of the portal vein may be misdiagnosed clinically in patients with hilar cholangiocarcinoma. However, the distance between tumor and adventitia is so narrow that curative resection without portal vein resection is unlikely to be possible. Gross portal vein invasion has a negative impact on survival, and hepatectomy with portal vein resection can offer long-term survival in some patients with advanced hilar cholangiocarcinoma.  相似文献   
20.
Changes in bone turnover markers during 14-day 6° head-down bed rest   总被引:1,自引:0,他引:1  
Osteoporosis caused by exposure to microgravity represents a serious clinical concern, but the mechanisms have yet to be fully elucidated. The present research aimed to elucidate the effects of microgravity environments on bone turnover, with a specific focus on changes in bone resorption markers such as type I collagen cross-linked N-telopeptides (NTx) and deoxypyridinoline (Dpyr), for which scant data are available regarding detailed time course. Methods using 6° head-down bed rest were utilized to simulate a microgravity environment. Eleven adult male volunteers underwent 6° head-down bed rest for 14 days; measurements were made of serum and urine Ca concentrations, in addition to osteocalcin (OC), bone alkaline phosphatase (ALP), NTx, and Dpyr as bone turnover markers. By the end of bed rest, concentrations of bone ALP had significantly increased, but OC displayed a tendency toward decrease. Concentrations of Dpyr significantly increased from day 6, remaining elevated until the end of bed rest. Concentrations of NTx significantly increased on day 13 and at the end of bed rest. Serum and urinary concentrations of Ca increased significantly at the end of bed rest. Bone ALP represents a relatively early marker of osteoblast differentiation at the matrix maturation phase and OC is a late marker in osteoblast differentiation at the calcification phase. The present results therefore suggest an absolute increase in bone resorption and normal or reduced bone formation, together causing prominent uncoupling and rapid bone loss after simulated microgravity. Moreover, the present results suggest that bone resorption is enhanced at an early stage of exposure to microgravity environments.  相似文献   
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