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991.
992.
The aim of this study was to determine factors that predict mortality in patients with traumatic inferior vena cava (IVC) injuries and to review the current management of this lethal injury. A 7-year retrospective review of all trauma patients with IVC injuries was performed. Factors associated with mortality were assessed by univariate analysis. Significant variables were included in a multivariate regression analysis model to determine independent predictors of mortality. Statistical significance was determined at P < or = 0.05. A literature review of traumatic IVC injuries was performed and compared with our institutional experience. Thirty-six IVC injuries were identified (mortality, 56%; mechanisms of injury, 28% blunt and 72% penetrating). There was no difference in mortality based on mechanism of injury. Injuries with closer proximity to the heart were associated with increased mortality (P < 0.001). Univariate analysis demonstrated that nonsurvivors had a higher injury severity scale, a lower systolic blood pressure in the emergency department, a lower Glasgow coma score (GCS), and were more likely to have thoracotomies performed in the emergency department or operating room. Multivariate analysis revealed that only GCS (P = 0.03) was an independent predictor of mortality. Typical factors predicting mortality were identified in our cohort of patients, including GCS. The mechanism of injury is not associated with survival outcome, although mortality is higher with injuries more proximal to the heart. The form of management by IVC level is reviewed in our patient population and compared with the literature. 相似文献
993.
Nguyen NT Luketich JD Schatz S Tran Q Ho HS Schauer PR 《Surgical laparoscopy, endoscopy & percutaneous techniques》1999,9(3):176-180
Immune suppression associated with trauma has been demonstrated to be proportional to the magnitude of injury. Laparoscopic surgery has been shown to produce a diminished stress response compared to open surgery. Postoperative immune function, specifically cellular immunity, may be better preserved after laparoscopic surgery compared to open surgery. The aim of this study was to examine the effect of open versus laparoscopic surgery on cellular immunity in a swine model. Twenty domestic female pigs were randomly selected for laparoscopic cholecystectomy (LC) or open cholecystectomy (OC). Cellular immune functions were evaluated with delayed-type hypersensitivity (DTH) skin test and serial phytohemoagglutinin (PHA)-induced T-cell proliferation of the peripheral blood. There was a significant reduction in PHA-induced T-cell proliferation in both LC and OC groups on days 1 and 3 compared to preoperative values (p < 0.05). The reduction of mitogen-induced T-cell proliferation after LC was significantly less than after OC on day 1 (p = 0.03). The mean DTH reaction was 29.7 +/- 3.7 mm2 in the LC group compared to 13.9 +/- 1.2 mm2 in the OC group (p < 0.001). There was no difference in postoperative white blood count values between the two groups. Suppression of cellular immunity occurred after both LC and OC. The magnitude and duration of impaired cellular immunity after laparoscopic surgery was less than after open surgery as measured by T-cell proliferation and DTH response. 相似文献
994.
颈椎不稳在交感型颈椎病发病中的作用 总被引:18,自引:0,他引:18
目的:研究交感型颈椎病的病理因素及治疗方法。方法:回顾分析了1988-2000年收治的20例手术治疗的交感型颈椎病患者。根据术前及术后颈椎伸屈侧位X光片判断有无颈椎不稳。结果:20例患者术前均有颈椎不稳,颈椎不稳主要发生在C3-C4和C4-C5,颈椎高位硬膜外封闭对大部分患者有短期效果。每例患者均于不稳节段行颈前路融合术,手术有效率为90%。结论:颈椎不稳是导致交感型颈椎病发病的重要因素;颈椎高位硬膜外封闭可有短期疗效因此具有重要的诊断价值;颈椎前路植骨融合术是治疗交感型颈椎病的有效方法。 相似文献
995.
N Corvisier F Gray R Gherardi F Lebras C M Blanc J P Nguyen J Poirier 《Surgical neurology》1987,28(4):311-315
A 54-year-old woman had been treated 26 years previously for Hodgkin's disease. Eight months before presentation, the disease had recurred and the patient had received cytotoxic drugs and steroids. She presented with loss of vision of the right eye and died 5 months later from extensive subarachnoid hemorrhage. Postmortem examination revealed an aspergillus abscess of the ethmoid sinus, extending to the right frontal lobe and optic nerve, and to the wall of the right internal carotid artery (ICA). Death was due to rupture of the ICA. Such a presentation of aspergillosis is unusual. Three cases of aspergillus arteritis causing rupture of the ICA have been reported previously. 相似文献
996.
Pulmonary hypertensive effect of heparin and protamine interaction: evidence for thromboxane B2 release from the lung 总被引:1,自引:0,他引:1
The characteristic pulmonary hypertensive effect of the heparin and protamine interaction has been studied in the isolated pig lung preparation using sequential autologous blood perfusate and dextran perfusate. A significant (p less than 0.001) increase in pulmonary artery pressure at constant flow was seen in 10 of 14 dextran and 12 of 15 blood perfusions. The average increase for dextran was 112 percent and for blood, 109 percent. Antihistamines did not inhibit the response. However, this was abolished in all 11 animals treated with aspirin. In 11 intact swine, thromboxane B2 blood levels increased significantly (p less than 0.01) from 0.46 +/- 0.38 ng/dl to 2.97 +/- 1.5 ng/dl. Thus, pulmonary hypertension associated with protamine reversal of heparinization is associated with prostaglandin release from the lung, and this does not require mediation of platelets or leukocytes. 相似文献
997.
Regulatory T cells (Tregs) are essential for the establishment and maintenance of immune tolerance, suggesting a potential therapeutic role for Tregs in transplantation. However, Treg administration alone is insufficient in inducing long‐term allograft survival in normal hosts, likely due to the high frequency of alloreactive T cells. We hypothesized that a targeted reduction of alloreactive T effector cells would allow a therapeutic window for Treg efficacy. Here we show that preconditioning recipient mice with donor‐specific transfusion followed by cyclophosphamide treatment deleted 70–80% donor‐reactive T cells, but failed to prolong islet allograft survival. However, infusion of either 5 × 106 Tregs with direct donor reactivity or 25 × 106 polyclonal Tregs led to indefinite survival of BALB/c islets in more than 70% of preconditioned C57BL/6 recipients. Notably, protection of C3H islets in autoimmune nonobese diabetic mice required islet autoantigen‐specific Tregs together with polyclonal Tregs. Treg therapy led to significant reduction of CD8+ T cells and concomitant increase in endogenous Tregs among graft‐infiltrating cells early after transplantation. Together, these results demonstrate that reduction of the donor‐reactive T cells will be an important component of Treg‐based therapies in transplantation. 相似文献
998.
Immobilization protocols for nondisplaced scaphoid fractures have included the elbow, wrist, and thumb. This study attempts
to demonstrate whether or not immobilization of the thumb makes a difference in preventing motion at the scaphoid fracture
site. Using six fresh frozen forearm specimens, a transverse waist scaphoid fracture was created through a dorsal approach.
Metallic markers were imbedded on either side of the fracture. Sutures were secured to the flexor pollicus longus (FPL) and
extensor pollicus longus (EPL). Each specimen was loaded in extension and flexion by attaching 50-g weights to the EPL and
FPL, first with no casting, then with a short arm cast, and finally a short arm thumb spica cast. Angulation and displacement
at the fracture site were measured in the coronal, sagittal, and axial planes utilizing image reconstructions from computed
tomography. One-way ANOVA with repeated measures and Tukey–Kramer multiple comparison test post hoc analysis were used for
statistical evaluation. There was no significant difference in fracture angulation or rotation between spica and short arm
casts. There was a significant difference in angulation and rotation in all three planes when comparing between casting and
no casting, p < 0.05. In our cadaveric model, wrist immobilization is crucial for nondisplaced scaphoid waist fractures, and short arm
casting was just as effective as thumb spica casting in preventing fracture displacement. 相似文献
999.
STUDY DESIGN: An in vitro biomechanical study using a simulated cervical corpectomy model to compare the load-sharing properties and stiffnesses of two static and two dynamic cervical plates. OBJECTIVES: To evaluate the load-sharing properties of the instrumentation with a full-length graft and with 10% graft subsidence and to measure the stiffness of the instrumentation systems about the axes of flexion-extension, lateral bending, and axial torsion under these same conditions. SUMMARY OF BACKGROUND DATA: No published reports comparing conventional and dynamic cervical plates exist. METHODS: Six specimens of each of the four plate types were mounted on ultra-high molecular weight polyethylene-simulated vertebral bodies. A custom four-axis spine simulator applied pure flexion-extension, lateral bending, and axial torsion moments under a constant 50 N axial compressive load. Load sharing was calculated through a range of applied axial loads up to 120 N. The stiffness of each construct was calculated in response to +/-2.5 Nm moments about each axis of rotation with a full-length graft, a 10% shortened graft, and no graft. ANOVA and Fisher's post hoc test were used to determine statistical significance (alpha < or = 0.05). RESULTS: The two locked cervical plates (CSLP and Orion) and the ABC dynamic plate were similar in flexion-extension, lateral bending, and torsional stiffness. The DOC dynamic plate was consistently less stiff. The Orion plate load shared significantly less than the other three plates with a full graft. Both the ABC and the DOC plates were able to load share with a shortened graft, whereas the conventional plates were not. CONCLUSIONS: All plates tested effectively load share with a full-length graft, whereas the two dynamic cervical plates tested load share more effectively than the locked plates with simulated graft subsidence. The effect of dynamization on stiffness is dependent on plate design. 相似文献
1000.
使用颗粒状自体松质骨植骨的寰枢椎后路融合术 总被引:21,自引:4,他引:21
介绍一种在头环背心保护下用颗粒状自体松质骨植骨的寰枢椎后路融合术。对34例寰枢椎不稳的病人施行了寰枢椎后路融合术。用头环背心维持寰椎的复位,将颗粒状的自体松质骨植于寰椎后弓和枢椎椎板的背面,不用内固定,直至植骨融合。31例病人获得了随访,平均随访时间30个月,其中29例融合成功,术后头不背心固定时间平均为13周,有3例出现了寰椎再移位。颗粒状自体松质骨比块状的全层骨更有利于融合。用头环背心的外固定 相似文献