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Crystalloid inclusions or "pole bodies" observed in brain macrophages in human demyelinating disease represent a morphological enigma. Similar inclusions were detected in brain macrophages from the GFAP-IL3 mouse, a transgenic murine model for macrophage mediated demyelination. Mice also showed inclusions in hematopoietic tissue. They appear to be related to phagocytosis and secretion, respectively, as evidenced by the fact that in phagocytosing cells they often merged with lysozomes and that affected cells showed empty channels open to the interstitium. Based on ultrastructural and immunolocalization studies using chaperonin-10, lysozyme, and cathepsin the authors suggest that these inclusions are consistent with phagocytosis-related secretory products. This study may provide insight into the nature and significance of similar macrophage inclusions recently identified in multiple sclerosis.  相似文献   
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This article serves as the introduction and historical perspective of anterior cruciate ligament surgery and rehabilitation. Several physician-therapist teams have been invited to share their "state of the art" techniques and to contrast their programs to that espoused by Shelbourne and Nitz in 1990. Our commentary/review of "Accelerated Rehabilitation After Anterior Cruciate Ligament Reconstruction" (Shelbourne KD, Nitz P, Am J Sports Med 18:292-299, 1990) is provided to contextualize the reader to what most clinicians would recognize as an extremely aggressive rehabilitation approach that is being popularized in the 1990s. A comparison is then presented of the rehabilitation sequence used in the MacIntosh procedures, demonstrating how early motion/functional rehabilitation was the hallmark of this type of extraarticular rehabilitation sequence and how today's pattern has evolved to follow that philosophy. Each of the teamed authors has attempted to present his surgery and rehabilitation/techniques and highlight differences between his program and that of Shelbourne and Nitz. We hope that the readers find this glimpse of the past and present helpful in formulating their rehabilitation sequences and that the future will be predicated on excellent basic science and clinical judgment. J Orthop Sports Phys Ther 1992;15(6):265-269.  相似文献   
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There has been increasing interest within the European sports medicine community regarding the etiology and treatment of groin pain in the athlete. Groin pain is most commonly caused by musculotendinous strains of the adductors and other muscles crossing the hip joint, but may also be related to abdominal wall abnormalities. Cases may be termed "pubalgia" if physical examination does not reveal inguinal hernia and there is an absence of other etiology for groin pain. We present nine cases of patients who underwent herniorrhaphies for groin pain. Two patients had groin pain without evidence of a hernia preoperatively (pubalgia). In the remaining seven patients we determined the presence of a hernia by physical examination. At operation, eight patients were found to have inguinal hernias. One patient had no hernia but had partial avulsion of the internal oblique fibers from their insertion at the public tubercle. The average interval from operation to return to full activity was 11 weeks. All patients returned to full activity within 3 months of surgery. One patient had persistent symptoms of mild incisional tenderness, but otherwise there were no recurrences, complications, or persistence of symptoms. Abnormalities of the abdominal wall, including inguinal hernias and microscopic tears or avulsions of the internal oblique muscle, can be an overlooked source of groin pain in the athlete. Operative treatment of this condition with herniorrhaphy can return the athlete to his sport within 3 months.  相似文献   
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Ahn UM  Ahn NU  Buchowski JM  Garrett ES  Sieber AN  Kostuik JP 《Spine》2000,25(12):1515-1522
STUDY DESIGN: A meta-analysis of surgical outcomes of cauda equina syndrome secondary to lumbar disc herniation. OBJECTIVES: To determine the relationship between time to decompression after onset of cauda equina syndrome and clinical outcome, and to identify preoperative variables that were associated with outcomes. SUMMARY OF BACKGROUND DATA: The timing of surgical decompression for cauda equina syndrome is controversial. Although most surgeons recommend emergent decompression, results in certain studies show that delayed surgery may provide a satisfactory outcome. METHODS: A meta-analysis was performed to determine the correlation between timing of decompression and clinical outcome. One hundred four citations were reviewed, and 42 met the inclusion criteria. Preoperative and postoperative data were recorded. Length of time to surgery was broken down into five groups: less than 24 hours, 24-48 hours, 2-10 days, 11 days to 1 month, and more than 1 month. Logistic regression was used to determine the association between preoperative variables and postoperative outcomes. RESULTS: Outcomes were analyzed in 322 patients. Preoperative chronic back pain was associated with poorer outcomes in urinary and rectal function, and preoperative rectal dysfunction was associated with worsened outcome in urinary continence. In addition, increasing age was associated with poorer postoperative sexual function. No significant improvement in surgical outcome was identified with intervention less than 24 hours from the onset of cauda equina syndrome compared with patients treated within 24-48 hours. Similarly, no difference in outcome occurred in patients treated more than 48 hours after the onset of symptoms. Significant differences, however, were found in resolution of sensory and motor deficits as well as urinary and rectal function in patients treated within 48 hours compared with those treated more than 48 hours after onset of symptoms. CONCLUSIONS: There was a significant advantage to treating patients within 48 hours versus more than 48 hours after the onset of cauda equina syndrome. A significant improvement in sensory and motor deficits as well as urinary and rectal function occurred in patients who underwent decompression within 48 hours versus after 48 hours.  相似文献   
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Mechanisms of anterior cruciate ligament injury   总被引:22,自引:0,他引:22  
This study examined the mechanisms of anterior cruciate ligament (ACL) injury. In the first part of the study, using a comprehensive, standardized questionnaire, 89 athletes (100 knees) were interviewed about the events surrounding their ACL injury. A noncontact mechanism was reported in 71 (72%) knees and a contact injury in 28 (28%) knees; one patient was unsure if there was any contact. Most of the injuries were sustained at footstrike with the knee close to full extension. Noncontact mechanisms were classified as sudden deceleration prior to a change of direction or landing motion, while contact injuries occurred as a result of valgus collapse of the knee. Hamstring flexibility parameters revealed a statistically higher level of laxity in the injured athletes compared with a matched group of 28 controls. In the second part of the study, videotapes of 27 separate ACL disruptions were reviewed and confirmed that most noncontact injuries occur with the knee close to extension during a sharp deceleration or landing maneuver. Because the knee is in a position to allow the extensor mechanism to strain the ACL and maximum, eccentric muscle force conditions usually apply, the quadriceps may play an important role in ACL disruption. Passive protection of the ACL by the hamstring muscles may be reduced in patients with above-average flexibility.  相似文献   
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