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41.
Hamstring injuries are common forms of muscle strains in athletes but a complete rupture of a proximal hamstring origin is rare. Often there is a considerable delay in diagnosis and stringent treatment because of its rarity, difficulty in clinical diagnosis, and initial attempts of conservative care. We report two cases of acute complete rupture of the proximal hamstring tendons treated with early surgical repair. The diagnosis and treatment of this unusual injury are discussed.  相似文献   
42.
BACKGROUND: We hypothesized that a dorsomedial locking plate with adjunct screw compression would provide superior rigidity compared to crossed screws for first metatarsocuneiform (MTC) arthrodesis. MATERIALS AND METHODS: In ten matched lower extremity pairs, specimens in each pair were randomly assigned to receive screw fixation or plate with screw fixation. Bone mineral density (BMD) was measured. For the crossed-screw construct, two 4.0-mm cannulated screws were used. One screw was inserted dorsal to plantar beginning from the first metatarsal 10 to 15 mm distal to the joint, and the second was inserted from the cuneiform 8 to10 mm proximal to the joint, medial to the first screw, into the first metatarsal. For the plate construct, a 4.0-mm cannulated compression screw was inserted from the dorsal cortex of the first metatarsal to the plantar aspect of the medial cuneiform. A locking plate was inserted dorsomedially across the MTC joint. Specimens were loaded in four-point bend configuration (displacement rate, 5 mm/min) until failure of the fixation or 3-mm deformation. An extensometer was used to measure deformation. RESULTS: There was no difference in load to failure or stiffness between the two groups. BMD was positively correlated with load to failure in the screw (r = 0.893, p = 0.001) and the plate (r = 0.858, p = 0.001) construct. CONCLUSION: The plate construct with compression screw did not show different rigidity as compared with the screw construct with the numbers available. CLINICAL RELEVANCE: Further investigation of a dorsomedial plate with adjunct screw compression may be warranted for first MTC arthrodesis.  相似文献   
43.
Background and objectives In breast cancer, the expression pattern of CXCR4 may be correlated with the degree of axillary lymph node involvement. The aim of this study was to evaluate the contributing factors that contribute to the correlation between CXCR4 expression and axillary lymph node metastasis in breast cancer. Methods Between August 1997 and August 2002, sections of paraffin-embedded tissue were obtained from 107 patients who received optimal treatment for breast cancer. The expression of CXCR4 was evaluated by immunohistochemical staining. Results A significant correlation was found in the expression of nuclear CXCR4 and lymph node metastasis (P = 0.03). We found a significant correlation between a high nuclear expression of CXCR4 and axillary lymphatic metastasis in estrogen and progesterone receptor negative breast cancer (P = 0.01 and P = 0.01). There was a significant correlation between the high expression of nuclear CXCR4 and axillary lymphatic metastasis in comparisons between positive estrogen and/or progesterone receptor expression and negative expression (P = 0.02). Conclusions Our results showed that high expression of nuclear CXCR4 was significantly correlated with lymph node metastasis in breast cancer. The high expression of nuclear CXCR4 in hormone receptor negative breast cancer was associated with a high possibility of lymph node metastasis.  相似文献   
44.
Bariatric surgery has serious associated medical comorbidity and procedure-related risks and is, thus, considered an intermediate-to-high-risk non-cardiac surgery. Altered respiratory mechanics, obstructive sleep apnea (OSA), and less often, pulmonary hypertension and postoperative pulmonary embolism are the major contributors to poor pulmonary outcomes in obese patients. Attention to posture and positioning is critical in patients with OSA. Suspected OSA patients requiring intravenous narcotics should be kept in a monitored setting with frequent assessments and naloxone kept at the bedside. Use of reverse Tredelenburg position, preinduction, maintenance of positive end-expiratory pressure, and use of continuous positive airway pressure can help improve oxygenation in the perioperative period.  相似文献   
45.
In patients with brachial plexus birth palsy, persistent muscular imbalance across the developing shoulder results in progressive glenohumeral dysplasia, characterized by increased glenoid retroversion, humeral head flattening, and posterior subluxation of the humeral head. Soft-tissue procedures-such as tendon transfers and musculotendinous lengthenings--will provide limited functional improvements in the setting of advanced glenohumeral deformity. For patients with internal rotation contracture and external rotation weakness associated with severe glenohumeral dysplasia, external rotation osteotomy of the humerus may be used to improve global shoulder function. The purpose of this article is to review the history, indications, and surgical technique of external rotation humeral osteotomy for patients with brachial plexus birth palsy.  相似文献   
46.
Background Endoscopic resection (ER) is an effective treatment for early gastric cancer (EGC) without lymph node metastasis. However, after ER additional surgery may be needed to manage the risks presented by residual cancer or lymph node metastasis. Methods ER was performed on 344 gastric adenocarcinomas between November 2001 and April 2006 at the Korean National Cancer Center under the strict pre-procedural indication. The authors performed operations in 43 patients due to: residual mucosal cancer, a mucosal cancer larger than 3 cm, or a submucosal cancer regardless of size or margin involvement. ER and surgical specimens were reviewed and analyzed for residual cancer and lymph node metastasis. Results Based on examinations of ER specimens, cancer was confined to the mucosal layer in 15 patients (34.9%) and invaded the submucosal layer in 28 patients (65.1%). Surgical specimens showed residual cancer in 17 patients (39.5%) and lymph node metastasis in four (9.3%). Neither residual cancer nor lymph node metastasis was found in patients with less than 500 μm submucosal invasion without margin involvement in ER specimens. In three of four patients with lymph node metastasis, the depth of submucosal invasion was 500 μm or more; the remaining patient had a 4-cm-sized differentiated mucosal cancer. Conclusions When a pathologic evaluation of an ER specimen reveals more than 500 μm of submucosal invasion or a mucosal cancer of larger than 3 cm, surgery should be considered due to the risk of lymph node metastasis.  相似文献   
47.
We report a case of ceramic liner fracture in a 34-year-old man that occurred 1 year 9 months after total hip arthroplasty with a BiCONTACT (Aesculap, Tuttlingen, Germany) ceramic-on-ceramic prosthesis. The ceramic liner was found within the metal shell in 4 large pieces and multiple small fragments in the peripheral portions. Its condition indicated that the possible mechanism of late ceramic liner chip fracture was repeated episodes of impingement between the prosthetic neck and the edge of the ceramic liner. Squatting, kneeling, and sitting cross-legged caused impingement. These positions are more common in Asian populations than in Western populations. After the joint was thoroughly irrigated, a new modular ceramic liner and a 28-mm ceramic head were implanted.  相似文献   
48.
49.

Introduction

CD151, a transmembrane protein of the tetraspanin family, is implicated in the regulation of cell-substrate adhesion and cell migration. Overexpression of CD151 has been reported in several cancers and controls MET-dependent neoplastic growth by enhancing receptor signaling. However, association of CD151 overexpression with MET or tumor progression has not been reported in gastric cancer.

Materials and Methods

We conducted immunohistochemical analysis of CD151 overexpression in 491 pT3 gastric carcinomas and analyzed the relationship with MET overexpression and prognostic significance.

Results

CD151 was highly expressed in 119 gastric carcinomas (24.2 %) and was significantly associated with higher pN stages. Patients with CD151-positive gastric cancer showed shorter overall (p = 0.003) and disease-free survival (p = 0.001) compared with patients with CD151-negative gastric carcinoma. CD151 overexpression was an independent prognostic factor for overall survival [hazard ration (HR) 1.335; 95 % CI 1.005–1.775; p = 0.046] and disease-free survival (HR 1.903; 95 % CI 1.348–2.685; p < 0.001). Co-overexpression of CD151 and MET was observed in 30 (6.1 %) gastric cancers and was more frequent in advanced pN stages than in other groups. Moreover, co-overexpression of CD151 and MET was a strong independent prognostic factor for overall survival (HR 3.163; 95 % CI 1.958–5.108; p < 0.001) and disease-free survival (HR 3.834; 95 % CI 2.145–6.852; p < 0.001).

Conclusion

CD151 overexpression is an independent prognostic factor and could be a potential molecular therapeutic target in patients with advanced gastric cancers. Further studies are needed to establish the biological significance of CD151/MET co-overexpression and the potential of targeting both molecules as a therapeutic strategy.  相似文献   
50.

Background

A number of recent reports have suggested that the cystatin C/creatinine (CysC/Cr) ratio might be a useful biomarker of renal function in pediatric patients. In this study we investigated the reference intervals of the serum CysC/Cr ratio for neonates including very low birth weight infants.

Case-Diagnosis/Treatment

A total of 883 blood samples were collected from 246 neonates during the first 30 days of life for the concurrent measurement of serum CysC and Cr levels. Infants with symptoms or signs of acute kidney injury, systemic illness, congenital anomaly, or renal pathology were excluded. The association between serum CysC/Cr ratio and the subgroups of patients was also analyzed. Reference intervals of serum CysC/Cr ratio were determined according to the postnatal age and post-conceptional age (PCA). CysC/Cr ratio level increased according to PCA, except in the first three postnatal days. The serum CysC/Cr ratio correlated positively with gestational age at birth, birth weight, postnatal age, and PCA, and negatively with serum CysC and Cr (P?<?0.001).

Conclusions

Reference levels of serum CysC/Cr ratio were determined according to postnatal age and PCA. As the serum CysC/Cr ratio is dependent on several clinical parameters, these should be considered when assessing the serum CysC/Cr ratio in neonates.  相似文献   
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