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101.
Malignant transformation of fibrous dysplasia is very rare and has not been previously described in patients with McCune–Albright syndrome in the absence of radiation treatment during gestation. Here, we report a 38-year-old pregnant woman with McCune–Albright syndrome and acromegaly accompanied by osteosarcoma. The patient was in the 6th week of pregnancy, when she visited our hospital. She had multiple fibrous dysplasia, skin pigmentation, and acromegaly. The markedly high bone turnover rate during pregnancy tended to decrease after a normal delivery. Fibrous dysplasia of the lower jaw rapidly increased in the 37th week of pregnancy, and the tumor was surgically resected after delivery. Pathological examination of the resected tumor revealed fibrous dysplasia admixed with osteosarcoma containing chondroblastic and osteoblastic tissue. We firstly reported a case of osteosarcoma in a patient with McCune–Albright syndrome, which rapidly progressed during pregnancy.  相似文献   
102.
Hypertrophic nonunion usually results from insufficient fracture stabilization. Therefore, most hypertrophic nonunions simply require the stabilization of the nonunion site. However, the reasons why union occurs without treating the nonunion site directly is not well understood biologically. In this study, we hypothesized that the intervening tissue at the hypertrophic nonunion site (nonunion tissue) could serve as a reservoir of mesenchymal progenitor cells and investigated whether the cells derived from nonunion tissue had the capacity for multilineage mesenchymal differentiation. After nonunion tissue was obtained, it was cut into strips and cultured. Homogenous fibroblastic adherent cells were obtained. Flow cytometry revealed that the adherent cells were consistently positive for mesenchymal stem cell related markers CD13, CD29, CD44, CD90, CD105, CD166, and negative for the hematopoietic markers CD14, CD34, CD45, and CD133, similar to control bone marrow stromal cells. In the presence of lineage‐specific induction factors, the adherent cells differentiated in vitro into osteogenic, chondrogenic, and adipogenic cells. These results demonstrated for the first time that hypertrophic nonunion tissue contains multilineage mesenchymal progenitor cells. This suggests that hypertrophic nonunion tissue plays an important role during the healing process of hypertrophic nonunion by serving as a reservoir of mesenchymal cells that are capable of transforming into cartilage and bone forming cells. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:208–215, 2009  相似文献   
103.

Purpose

The present study aimed to assess the safety and feasibility of laparoscopic extended pelvic surgery for primary or recurrent rectal cancer.

Methods

The data on 77 patients, who underwent extended pelvic surgery between February 2008 and June 2014, were retrospectively analyzed. The patients were divided, based on their treatment history, into an open surgery (OS) group (n = 41) and a laparoscopic surgery (LS) group (n = 36).

Results

The operative time in the LS group was significantly longer than that in the OS group (766 vs. 561 min; p < 0.001). In contrast, the LS group was associated with a significantly lower volume of intraoperative blood loss (195 vs. 923 ml; p < 0.001), fluid balance (5.38 vs. 8.23 ml/kg/h; p < 0.001) and rate of complications (40.0 vs. 68.3 %; p = 0.035), and a significantly shorter postoperative hospital stay. The postoperative levels of colloid osmotic pressure and albumin were significantly higher in the LS group.

Conclusion

The operative time of the LS group was longer than that of the OS group; however, the LS group experienced less blood loss and fewer complications. Moreover, LS was associated with a reduction in intraoperative infusions and a reduced fluid balance, which maintained homeostasis.
  相似文献   
104.

Background

CD133 is a transmembrane protein that is proposed to be a stem cell marker of colorectal cancer (CRC); however, the correlation between CD133 expression and survival of CRC patients with liver metastasis has not been fully examined.

Methods

CD133 expression was evaluated immunohistochemically, both in primary tumors and synchronous liver metastases of 88 consecutive CRC patients, as well as recurrent lesions in the remnant liver of 27 of these 88 patients. The relationship between CD133 expression and clinicopathological characteristics, recurrence-free survival, and overall survival (OS) was analyzed.

Results

CD133 expression in liver metastases (mCD133) was detected in 50 of 88 patients (56.8 %), and had significant correlation with CD133 expression in primary lesions (pCD133) (p < 0.001). CD133 expression in liver recurrent lesions (recCD133) also had a significant correlation with mCD133 (p < 0.001). mCD133+ patients had significantly longer disease-free survival (p = 0.043) and OS (p = 0.014) than mCD133? patients. In addition, mCD133+ patients had a significantly lower rate of extrahepatic recurrence (p < 0.001).

Conclusions

Patients without CD133 expression in liver metastasis had significantly shorter survival, perhaps because mCD133? patients had a significantly higher rate of extrahepatic recurrence.
  相似文献   
105.
Effort angina of a 70-year-old man was diagnosed as due to triple coronary vessel disease, and he was scheduled to undergo coronary artery bypass surgery. Preoperative carotid duplex scan revealed more than 75% stenosis of the right internal carotid artery, which was functionally proven to be significantly ischemic on brain single photon emission computed tomography. Although he was neurologically asymptomatic, we chose staged surgery for fear of stroke during coronary artery bypass surgery. He had successful carotid artery stenting first by neurosurgeons; then, 2 months later he underwent uneventful coronary artery bypass surgery. This experience prompted us to report the case.  相似文献   
106.
A 56-year-old female with congestive heart failure was transferred to our institution. Aortography demonstrated aortic valve stenosis (AS) with a congenitally bicuspid valve and dilatation of the ascending aorta. Preoperative coronary angiography showed a left single coronary artery. Replacement of the aortic valve and ascending aorta was performed. She had an uneventful postoperative course. We report the case of aortic bicuspid valve stenosis with single coronary artery as an extremely rare congenital cardiac anomaly combination.  相似文献   
107.

OBJECTIVE

To investigate the effect of a free‐radical scavenger, edaravone, on the changes occurring with acute urinary retention (AUR) and subsequent catheterization in the rat bladder.

MATERIALS AND METHODS

Eight‐week‐old male Sprague Dawley rats were allocated to one of four groups; an AUR group that had urinary retention induced, with subsequent catheterization; two edaravone groups, given edaravone at 1 or 10 mg/kg body weight for 60 min and then the same urinary retention and subsequent catheterization; and a sham‐operated control group given edaravone 10 mg/kg. Urinary retention was induced by the clamping the rat penile urethra with a small clip, making a cystostomy, and then infusing 3 mL (0.6 mL/min) of saline with an infusion pump. The obstruction was sustained for 30 min and then the bladder was allowed to drain with a catheter in place for 60 min as the studies continued. After killing the rats the function of the bladder was assessed, with carbachol and 100 mm KCl, and the levels of malondialdehyde (MDA, a marker of lipid peroxidation), 8‐hydroxydeoxyguanosine (8‐OHdG; a marker of oxidative DNA damage), heat‐shock protein 70 (HSP 70) and its mRNA were measured.

RESULTS

AUR increased the intravesical pressure and decreased blood flow, and subsequent catheterization decreased the intravesical pressure and increased blood flow. Edaravone induced a decrease in blood flow in the bladder during the urinary retention and subsequent catheterization compared to the blood flow in the AUR group. Edaravone resulted in protection of the contractile responses to both carbachol and KCl in a dose‐dependent manner. The MDA concentration, 8‐OHdG content and expressions of HSP‐70 and its mRNA in the AUR group were significantly larger than those of the control group. Edaravone markedly suppressed the accumulations of MDA and 8‐OHdG in the bladder, and reduced the expressions of HSP 70 and its mRNA.

CONCLUSION

These results indicate that edaravone reduces the oxidative stress and prevents the bladder dysfunction caused by AUR and subsequent catheterization.  相似文献   
108.

Purpose

No studies have used stress analysis with finite element analysis (FEA) to determine the causes of and mechanisms underlying rotator cuff tears. Therefore, we performed a biomechanical evaluation of the changes in stress distribution on the rotator cuff using three-dimensional (3-D) FEA.

Methods

The 3-D FEA model of shoulder joint allowed for abduction angles of 0°, 45° and 90° from the plane of the scapula and included the anatomical insertion points of the three major rotator cuff tendons and the middle fibres of the deltoid muscle. Stress distribution of the supraspinatus tendon on 3-D FEA was validated by a comparison with cadaveric and two-dimensional finite element model.

Results

The principal stress peaked in the region approximately 1 cm proximal to the insertion of the supraspinatus tendon. Furthermore, the stress on the joint side increased at the anterior edge of the supraspinatus tendon at abduction angles of 45° and 90°.

Conclusion

There are differences in stress changes between the joint side and bursal side of the supraspinatus tendon within the angles of abduction. The maximal tensile stress was observed on the articular side of the anterior edge of the supraspinatus tendon at 90° abduction. Our results indicate that the difference in tensile stress between the two layers results in delamination and causes partial-thickness tears.

Level of evidence

Decision analysis, Level II.  相似文献   
109.

Purpose

The purpose of this study was to assess the efficacy of diffusion-weighted (DW) MR imaging for the differentiation between suppurative lymphadenitis and malignancy in necrotic cervical lymph nodes.

Materials and methods

Fifteen patients with suppurative lymphadenitis, 40 with squamous cell carcinoma (SCC), eight with lymphoma, and six with thyroid cancer were accompanied by necrotic cervical nodes. All 69 patients underwent 1.5-T MR imaging including DW and 58 underwent gadolinium-enhanced MR imaging. Necrotic area-to-spinal cord signal intensity ratios (SIR) on T1-, T2- and DW images and apparent diffusion coefficients (ADCs) [10−3 mm2/s] were correlated with the pathologies.

Results

Nineteen necrotic cervical nodes with suppurative lymphadenitis, 67 with SCC, 10 with lymphoma, and 12 with thyroid cancer were identified. SIR on DW images was higher in suppurative lymphadenitis (2.50 ± 1.21) than in malignancies (1.29 ± 0.67) (p < .01), and ADC value was lower in suppurative lymphadenitis (0.89 ± 0.21) than in malignancies (1.46 ± 0.46) (p < .01). SIR on T1-weighted images was higher in thyroid cancer (1.95 ± 0.53) than in suppurative lymphadenitis (0.87 ± 0.17), SCC (0.92 ± 0.13), and lymphoma (0.95 ± 0.09) (p < .01). No significant difference in SIR on T2-weighted images was found between suppurative lymphadenitis (1.46 ± 0.50) and malignancies (1.61 ± 0.56).

Conclusion

DW imaging with ADC measurements may play a supplementary role in the differentiation of necrotic cervical nodes between suppurative lymphadenitis and malignancy.  相似文献   
110.
PURPOSE: The volar region of the scapholunate interosseous ligament is one of the key structures that maintains scapholunate alignment. It is, however, difficult to evaluate this ligament using standard diagnostic procedures, including the arthroscopy through a dorsal portal. We have performed arthroscopic evaluation of this ligament through a volar portal. METHODS: Skin incision was made at just radial of the flexor carpi radialis tendon and the portal was opened through the tendon sheath. RESULTS: The volar approach enabled us to directly observe the extent of the tear of the volar region of scapholunate interosseous ligament. A shaver is inserted through the dorsal portal, and debridement can be performed by using the volar portal vein. We have not had any complications using volar portal. CONCLUSION: Volar approach is a feasible and safe procedure to evaluate and treat the volar region of the scapholunate interosseous ligament.  相似文献   
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