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91.

Background

Current reports on nipple-sparing mastectomy (NSM) are limited to single-institution series. We use the National Cancer Institute's Surveillance, Epidemiology, and End Results database to report on the national experience with NSM.

Methods

Population-level deidentified data were extracted from the Surveillance, Epidemiology, and End Results database. All female breast cancer patients treated with NSM from 2005 to 2009 were included. Case analysis was performed with respect to demographic and oncologic characteristics.

Results

Four hundred forty-nine patients underwent therapeutic NSM; this number increased from 66 patients in 2005 to 133 in 2009. Patients were distributed across 16 regions, although nearly 50% were from a region of California. Tumor diameter was <2 cm in 224 patients (50%). Lymph nodes were positive in 59 patients (13%), while radiation was delivered to 74 patients (16%).

Conclusions

NSM use has been increasing over the past several years. A majority of patients have tumor size <2 cm, although the number of patients with tumor size ≥2 cm has increased over time. Further population-based studies of NSM may benefit from collection of oncologic data such as tumor-to-nipple distance and tumor location.  相似文献   
92.

Background

Peripheral nerve injury can result in muscle atrophy and long-term disability. We hypothesize that creating a side-to-side bridge to link an injured nerve with a healthy nerve will reduce muscle atrophy and improve muscle function.

Methods

Sprague-Dawley rats were divided into four groups (n = 7 per group). Group 1: transection only—a 10-mm gap was created in the proximal tibial nerve; group 2: transected plus repaired—the transected tibial nerve was repaired; group 3: transected plus repaired plus nerve bridge—transected nerve repaired with a distal nerve bridge between the tibial and peroneal nerves via epineurial windows; and group 4: transected plus nerve bridge—transected tibial nerve left unrepaired and distal bridge added. Gait was assessed every 2 wk. At 90 d the following measures were determined: gastrocnemius mass, muscle and nerve nuclear density, and axonal infiltration into the nerve bridge.

Results

Groups 3 and 4 had greater improvements in walking track recovery than groups 1 and 2. Group 3's gastrocnemius muscles exhibited the least amount of atrophy. Groups 1, 2, and 4 exhibited greater histologic appearance of muscle breakdown compared with group 3 and control muscle. Finally, most bridges in groups 3 and 4 had neuronal sprouting via the epineurial windows.

Conclusions

Our study demonstrated reduced muscle atrophy with a side-to-side nerve bridge in the setting of peripheral nerve injury. These results support the application of novel side-to-side bridges in combination with traditional end-to-end neurorrhaphy to preserve muscle viability after peripheral nerve injuries.  相似文献   
93.
94.

Background

We aimed to assess the results of ligament reconstruction/advancement for the management of ligament insufficiency during total knee arthroplasty.

Method

We retrospectively reviewed the results of ligament reconstruction/advancement for management of instability due to ligament insufficiency during total knee arthroplasty (TKA). Between January 2001 and January 2008 collateral ligament reconstruction/advancement was done in 15 patients. Wherever ligament advancement was not possible (mid-substance tear) ligament reconstruction was done using the hamstring tendon. Knee society scores were calculated and Kaplan–Meier survival analysis was done.

Results

Average follow-up was 6.2 years. No patient developed instability until the last follow-up, except one patient who required revision due to instability at six years after primary surgery.

Conclusion

We concluded from this study that ligament reconstruction/advancement during TKA is a viable option to address instability due to ligament insufficiency.  相似文献   
95.
AIM: To identify their diagnostic and prognostic clinical characteristics in a large series.METHODS: Retrospective review of clinicopathologic and imaging characteristics of patients diagnosed with lymphoepithelial cysts and cystic lymphangiomas of the pancreas at Massachusetts General Hospital.RESULTS: Twelve patients were identified between 1/1/1997 and 8/1/2007. Their median age was 55.5 years(range 19-78 years), and 6 were females. The le-sion was incidentally discovered in half of the patients.Contrast enhanced computed tomography demonstrat-ed that the cysts had thin walls, without calcifications, pancreatic duct dilation or pancreatic parenchyma inva-sion. Endoscopic ultrasound with fine needle aspiration(EUS/FNA) confirmed the diagnosis of a lymphoepithe-lial cyst in 3 patients, one of whom was spared an op-eration and continues to do well after 6 years. Eleven patients had a resection: 3 pancreaticoduodenecto-mies, 7 distal pancreatectomies, and 1 enucleation. The median size of the cysts was 3 cm(range 2-20 cm). At a median follow-up of 57 mo no recurrences or other pancreas-related conditions occurred.CONCLUSION: Lymphoepithelial cysts and cystic lymphangiomas of the pancreas can be diagnosed with a combination of contrast-enhanced computed tomog-raphy scans and EUS/FNA. If the lesion is asymptom-atic, an operation might be avoided.  相似文献   
96.
Seminal oxidative stress (OS) is a major cause of male factor infertility and can be measured as oxidation–reduction potential (ORP). Studies showed significant negative relationships of ORP with sperm count, motility or DNA integrity. Since these parameters are also positively or negatively associated with reproductive hormones follicle‐stimulating hormone (FSH), luteinising hormone (LH), testosterone, testicular volume and the occurrence of varicocele, it is important to understand the mechanistic relationship between ORP and hormonal and/or testicular parameters. Therefore, we studied the relationship between ORP levels, standard hormone profiles and testicular volume in infertile men with and without varicocele. Results show a highly significant negative relationship of ORP with testicular volume and significantly positive correlations with FSH and LH. Yet, when adding varicocele as covariate, the relationship with FSH/LH became nonsignificant. Contrary, the presence of varicocele had only a contributing influence on the association of ORP with the testis volume. No association was found with estradiol. We propose that since OS causes degeneration of Sertoli cell with testicular shrinkage, such negative effect would result in a negative feedback on the hypothalamus with less inhibin secretion. This may result in increased secretion of LH and FSH. Thus, systemic and/or local OS may be responsible for smaller testis volumes.  相似文献   
97.
Die laparoskopische Chirurgie hat sich in den letzten Jahren zunehmend verbreitet und sich für einige Indikationen sogar zum Goldstandard entwickelt. Auch für kolorektale Eingriffe wird der laparoskopische Zugang zunehmend benutzt, wobei jedoch im Hinblick auf die Sicherheit bei onkologischen Koloneingriffen noch keine abschließende Beurteilung möglich ist. Die operative Therapie der Rektumkarzinome, die durch die Einführung der totalen mesorektalen Exzision (TME) zusätzliche Vorteile hinsichtlich der Rate an Lokalrezidiven erfahren hat, war bislang nicht Gegenstand der laparoskopischen Operationstechnik, da die angenommene Lernkurve und die fragliche onkologische Sicherheit einen derartigen Therapieansatz nicht zuließen.In der hier diskutierten Studie wurde bei Patienten mit Rektumkarzinom die Operation mit TME laparoskopisch durchgeführt. Es konnte gezeigt werden, dass sowohl die onkologischen Ergebnisse (Rezidivrate und Überleben) als auch das kurzfristige Outcome (Mortalität und Morbidität) mit den Ergebnissen der konventionell durchgeführten Operation vergleichbar sind. Ferner bleiben für die Patienten die von anderen laparoskopischen Operationen bekannten Vorteile (Schmerzreduktion, frühe Mobilisation, frühe Darmpassage) erhalten. Die Weiterentwicklung der laparoskopischen Technik könnte hier noch weitere Vorteile bringen, sofern die Konversionsrate zum konventionellen Verfahren durch adäquate Patientenselektion begrenzt werden kann.  相似文献   
98.

Introduction

Anterior cervical decompression and fusion is a well-established procedure for treatment of degenerative disc disease and cervical trauma including flexion-distraction injuries. Low-profile interbody devices incorporating fixation have been introduced to avoid potential issues associated with dissection and traditional instrumentation. While these devices have been assessed in traditional models, they have not been evaluated in the setting of traumatic spine injury. This study investigated the ability of these devices to stabilize the subaxial cervical spine in the presence of flexion-distraction injuries of increasing severity.

Methods

Thirteen human cadaveric subaxial cervical spines (C3–C7) were tested at C5–C6 in flexion–extension, lateral bending and axial rotation in the load-control mode under ±1.5 Nm moments. Six spines were tested with locked screw configuration and seven with variable angle screw configuration. After testing the range of motion (ROM) with implanted device, progressive posterior destabilization was performed in 3 stages at C5–C6.

Results

The anchored spacer device with locked screw configuration significantly reduced C5–C6 flexion–extension (FE) motion from 14.8 ± 4.2 to 3.9 ± 1.8°, lateral bending (LB) from 10.3 ± 2.0 to 1.6 ± 0.8, and axial rotation (AR) from 11.0 ± 2.4 to 2.5 ± 0.8 compared with intact under (p < 0.01). The anchored spacer device with variable angle screw configuration also significantly reduced C5–C6 FE motion from 10.7 ± 1.7 to 5.5 ± 2.5°, LB from 8.3 ± 1.4 to 2.7 ± 1.0, and AR from 8.8 ± 2.7 to 4.6 ± 1.3 compared with intact (p < 0.01). The ROM of the C5–C6 segment with locked screw configuration and grade-3 F-D injury was significantly reduced from intact, with residual motions of 5.1 ± 2.1 in FE, 2.0 ± 1.1 in LB, and 3.3 ± 1.4 in AR. Conversely, the ROM of the C5–C6 segment with variable-angle screw configuration and grade-3 F-D injury was not significantly reduced from intact, with residual motions of 8.7 ± 4.5 in FE, 5.0 ± 1.6 in LB, and 9.5 ± 4.6 in AR.

Conclusions

The locked screw spacer showed significantly reduced motion compared with the intact spine even in the setting of progressive flexion-distraction injury. The variable angle screw spacer did not sufficiently stabilize flexion–distraction injuries. The resulting motion for both constructs was higher than that reported in previous studies using traditional plating. Locked screw spacers may be utilized with additional external immobilization while variable angle screw spacers should not be used in patients with flexion-distraction injuries.  相似文献   
99.
100.
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