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101.
Hayes KC  Askes HK  Kakulas BA 《Spinal cord》2002,40(10):544-547
STUDY DESIGN: Case report of a 68-year-old male who sustained cervical trauma following a bodysurfing accident. OBJECTIVE: To describe the pathology of a relatively uncommon mechanism of injury involving extradural cord compression associated with traumatic disc protrusion and herniation, following a cervical hyperextension injury in which there was no vertebral fracture or residual subluxation. SETTING: Department of Neuropathology, Royal Perth Hospital, West Australia. METHOD: Postmortem pathology report. RESULTS: Evidence of multiple ruptures of anterior longitudinal ligament with posterior intervertebral disc herniation and three discrete foci of central cord hemorrhage. CONCLUSION: Observations are consistent with cervical extension injury and an injury vector that involves intense axial loading sufficient to cause multiple disc failures, disc herniation and retropulsion leading to extradural disc compression and cord hemorrhage.  相似文献   
102.
103.
Background The optimal strategy for incorporating lymphatic mapping and sentinel lymph node biopsy into the management of breast cancer patients receiving neoadjuvant chemotherapy remains controversial. Previous studies of sentinel node biopsy performed following neoadjuvant chemotherapy have largely reported on patients whose prechemotherapy, pathologic axillary nodal status was unknown. We report findings using a novel comprehensive approach to axillary management of node-positive-patients receiving neoadjuvant chemotherapy. Methods We evaluated 54 consecutive breast cancer patients with biopsy-proven axillary nodal metastases at the time of diagnosis that underwent lymphatic mapping with nodal biopsy as well as concomitant axillary lymph node dissection after receiving neoadjuvant chemotherapy. All cases were treated at a single comprehensive cancer center between 2001 and 2005. Results The sentinel node identification rate after delivery of neoadjuvant chemotherapy was 98%. Thirty-six patients (66%) had residual axillary metastases (including eight patients that had undergone resection of metastatic sentinel nodes at the time of diagnosis), and in 12 cases (31%) the residual metastatic disease was limited to the sentinel lymph node. The final, post-neoadjuvant chemotherapy sentinel node was falsely negative in three cases (8.6%). The negative final sentinel node accurately identified patients with no residual axillary disease in 17 cases (32%). Conclusions Sentinel lymph node biopsy performed after the delivery of neoadjuvant chemotherapy in patients with documented nodal disease at presentation accurately identified cases that may have been downstaged to node-negative status and can spare this subset of patients (32%) from experiencing the morbidity of an axillary dissection.  相似文献   
104.
We investigated the effect of ibandronate on three-dimensional (3-D) microstructure and bone mass in experimentally induced tumor osteolysis. Walker carcinosarcoma cells were implanted into the left femur of female rats that received 26-day ibandronate pretreatment followed by continued therapy or ibandronate posttreatment only. A tumor-only group received isotonic saline. At endpoint, excised femurs were scanned using microcomputed tomography (μCT) to assess bone volume density, bone mineral content, trabecular number/thickness, and separation for cortical plus trabecular bone or trabecular bone alone. Compared with the nonimplanted right femur, bone volume and surface density and trabecular number and thickness were reduced in the distal left femur following tumor cell implantation. μCT analysis revealed greater cortical and trabecular bone mineral content in the preventative and interventional (pre-post tumor) ibandronate group, and the interventional (post-tumor) ibandronate group, versus the tumor-only group. Bone volume density was significantly higher in pre-post and post-tumor groups compared to the tumor-only group. After preventative and interventional ibandronate, bone volume density and trabecular thickness were 13% and 60% greater, respectively, than in the post-tumor treatment group. 3-D μCT images confirmed microstructural changes. We conclude that combined interventional and preventative ibandronate preserves bone strength and integrity more than intervention alone.  相似文献   
105.
BACKGROUND: We reviewed the outcomes of oropharyngeal squamous cell carcinoma treated with external beam radiation and interstitial brachytherapy. METHODS: Ninety patients with squamous cell carcinoma of the oropharynx were treated with interstitial brachytherapy at the University of Utah between 1984 and 2001. Seventy-two patients received external beam radiotherapy (EBRT) followed by brachytherapy boost, 11 had surgery followed by EBRT and brachytherapy, 4 had surgery and brachytherapy, and 3 were treated with brachytherapy alone. Median doses for EBRT and brachytherapy were 50 and 24 Gy, respectively. RESULTS: Median follow-up after brachytherapy was 48.3 months for all patients. Five-year local control, disease-free survival, and overall survival were 76%, 61%, and 55%. For T1, T2, T3, and T4, 5-year local control rates were 83%, 79%, 79%, and 64%, respectively. Severe complications occurred in 13 patients, including 2 treatment-related deaths. CONCLUSIONS: EBRT combined with interstitial brachytherapy provide good local control rates for locally advanced oropharyngeal squamous cell carcinoma.  相似文献   
106.
OBJECTIVE: The outcome of immediate repair of obstetric third-degree tears is poorly documented. Immediate repair may give better functional results than delayed repair because scarring is reduced. This aim of this prospective study was to examine the early outcome of immediate repair of third-degree tears. METHOD: A total of 121 women who had immediate repair of obstetric third-degree tears underwent interview, anal ultrasonography and anorectal physiology. RESULTS: At review, 79 (65%) were completely asymptomatic (score = 0), 23 (19%), had minor flatus incontinence or mild urgency causing no compromise to their quality of life (score 1-4), and 19 (16%) had clinically embarrassing faecal incontinence (score 5-24). Thirty-nine (32%) had an intact internal anal sphincter (IAS) and external anal sphincter (EAS) (i.e. a successful repair), eight (7%) had a defect in the IAS alone but the EAS was intact (i.e. a successful repair but a residual IAS defect), 43 (35%) had a residual defect in the EAS alone (IAS intact) and 31 (26%) had a persistent defect in the IAS and EAS. Residual defects in either or both of the sphincters were associated with a significantly higher incidence of abnormal resting and squeeze anal pressures. Anal manometry had no correlation with symptoms. The highest proportion of severe incontinence was in those with an IAS defect alone (37%) and when there was a residual IAS and EAS defect (24%). Only 2 of 39 (5%) with an intact IAS and EAS had severe incontinence and only 8 of 43 (18%) with a residual EAS defect alone had severe faecal incontinence. CONCLUSION: These results indicate a good outcome following immediate repair of third-degree obstetric tears and emphasize the role of the IAS in providing continence.  相似文献   
107.
Background After neoadjuvant chemotherapy, women with locally advanced breast cancer (LABC) undergo a modified radical mastectomy or lumpectomy with axillary lymph node dissection (ALND) and radiotherapy. Sentinel lymphadenectomy (SL) is accepted for axillary evaluation in early breast cancer. We assessed the feasibility and predictive value of SL after neoadjuvant chemotherapy. Methods Eligible women received neoadjuvant therapy for LABC and were scheduled to undergo a definitive surgical procedure. Vital blue dye SL was attempted followed by level I and II axillary dissection. Results SL was successful in 29 of 34 patients (detection rate, 85%). Thirteen patients (45%) had positive nodes, and eight (28%) had negative nodes on both SL and ALND. In five patients (17%), the sentinel node was the only positive node identified. Overall, there was a 90% concordance between SL and ALND. The false-negative rate and negative predictive value were 14% and 73%, respectively. Among the subgroup without inflammatory cancer, the detection and concordance rates were 89% and 96%, respectively. The false-negative rate was 6%, and the negative predictive value was 88%. Conclusions SL after neoadjuvant chemotherapy may reliably predict axillary staging except in inflammatory breast cancer. Further studies are required to assess the utility of SL as the only mode of axillary evaluation in these women.  相似文献   
108.
Peripheral nerve repair is often complicated by fibroblastic scar formation, nerve dysfunction, and traumatic neuroma formation. Use of bio‐absorbable protective wraps may improve outcomes of these repairs. This study histologically compared the incidence of neuroma formation, connective tissue proliferation, and axonal regrowth in transected rat sciatic nerves repaired with and without tubular collagen nerve sleeves. Twenty Sprague‐Dawley rats underwent unilateral sharp sciatic nerve transection and microscopic nerve repair with four epineural sutures and were randomly treated with or without an encircling collagen nerve sleeve. Normal nerves from the contralateral sciatic nerve were also examined. At sacrifice three months later, the nerves were evaluated for traumatic neuroma formation, perineural scar formation, and morphometric analysis. Histological examination of normal and repaired nerves by a neuropathologist demonstrated healing, minimal Wallerian degeneration and no traumatic neuroma formation. Distal section analysis (nine nonwrapped, 10 wrapped), revealed no significant differences in total fascicular area, myelinated fibers per nerve, fiber density, myelin area per nerve, myelinated fiber diameter, axon diameter, myelin thickness, or G‐ratio. Significantly greater (P = 0.005) inner epineural connective tissue formation was observed in nonwrapped nerves (0.62 mm2 ± 0.2) versus wrapped nerves (0.35 mm2 ± 0.16). The ratio of connective tissue to fascicular area was larger in nonwrapped (1.08 ± 0.26) versus wrapped nerves (0.63 ± 0.22) (P < 0.001). This study demonstrated decreased inner epineural connective tissue formation with use of a collagen nerve wrap during primary repair of peripheral nerve transection in a rat sciatic nerve model. © 2010 Wiley‐Liss, Inc. Microsurgery 30:392–396, 2010.  相似文献   
109.
4-Aminopyridine (4-AP) is a potassium (K+) channel blocking agent that has been shown to reduce the latency and increase the amplitude of motor evoked potentials (MEPs) elicited with transcranial magnetic stimulation (TMS) in patients with chronic spinal cord injury (SCI). These effects on MEPs are thought to reflect enhanced conduction in long tract axons brought about by overcoming conduction deficits due to focal demyelination and/or by enhancing neuroneuronal transmission at one or more sites of the neuraxis. The present study was designed to obtain further evidence of reduced central motor conduction time (CMCT) and to determine whether MEPs could be recorded from paretic muscles in which they were not normally elicited. MEPs were elicited with TMS being delivered to subjects (n = 25) pre- and post-administration of 4-AP (10 mg capsule) or placebo. The principal finding was that 4-AP lowered the stimulation threshold, increased the amplitude and reduced the latency of MEPs in all muscles tested, including those that were unimpaired, but did not alter measures of the peripheral nervous system (i.e., M-wave, H-reflex, F-wave). These 4-AP-induced changes in MEPs were significantly greater than those seen with placebo (p < 0.05). The primary implication of these results is that a low dose of 4-AP (immediate-release formulation) appears to improve the impaired central motor conduction of some patients with incomplete SCI. This is most likely attributable to overcoming conduction deficits at the site of injury but may also involve an increase in cortical excitability.  相似文献   
110.

INTRODUCTION

The NHS Cancer Plan was introduced in 2000 and included guidelines for the rapid assessment and referral of cases of suspected malignancy. We wished to assess the efficiency and appropriateness of patients referred under the Department of Health''s general practitioner referral guidelines implemented for sarcomas in December 2000.

PATIENTS AND METHODS

A retrospective case-note review was performed of all patients referred to our regional soft tissue sarcoma unit between 1 January 2004 and 31 December 2008. Patients referred under the two-week guidelines and all patients referred routinely were analysed. The main outcome measures were the total number of patients referred on the basis of the two-week guidelines and the proportion they constitute of all referrals. The referring criteria were noted and compared to the observed criteria recorded. The final histo-logical diagnosis of patients referred on the basis of the two-week guidelines are documented.

RESULTS

A total of 2746 referrals for suspected sarcoma were made from January 2004 to December 2008. Of these, 154 referrals were made under the two-week rule of which 102 were referred purely on the clinical criteria for suspected soft tissue sarcoma. The remaining patients were referred after non-urgent special investigations indicated the possibility of sarcoma. Twelve patients referred under the two-week rule were proved to have sarcoma, nine after specific investigations including imaging or histological diagnosis. Of the 102 patients referred on clinical suspicion of a sarcoma, two patients had proven soft tissue sarcomas and one patient a cutaneous sarcoma. Between 2004 and 2008, the number of 2-week referrals rose 25-fold but accounted for an increase of less than 1% of the sarcomas treated in this unit.

CONCLUSIONS

The numbers of all referrals for suspected sarcoma are increasing; however, the rate of increase of 2-week referrals is increasing faster than routine referrals and will exceed it in 2012 if current trends continue. There has not been a commensurate rise in the detection of sarcoma or, more specifically, diagnosis of the deep sarcomas associated with worse prognosis. Current clinical guidelines have essentially had no impact on the early diagnosis and treatment of soft tissue sarcoma, and may negatively impact on the treatment of patients with proven sarcoma by delaying treatment within a regional centre because of redirection of a large number of patients with benign abnormalities to such centres.  相似文献   
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