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961.
OBJECTIVES: Endograft repair holds considerable promise in the treatment of traumatic disruption of the thoracic aorta because patients often have multiple coexisting injuries further complicating traditional open repair. In addition, patients are often young, with an aortic anatomy dissimilar to those with atherosclerotic aneurysms. As a result, techniques for endograft repair have to be refined accordingly. METHODS: The records of 20 consecutive cases of traumatic aortic disruption treated by endograft repair at a single institution were reviewed. RESULTS: Mean patient age was 40 years (range, 17 to 88 years), and 17 (85%) of 20 patients were men. All cases were completed. There were no procedure related deaths, but four (20%) patients died of their co-injuries. Only two (10%) of 20 required a graft >28 mm in diameter, and nine (45%) aortas were small enough to require use of 23-mm abdominal cuffs. Six (30%) of 20 cases required complete or partial coverage of the left subclavian artery. Placement of a proximal extension was required in one patient for a type I endoleak. A graft collapse occurred in one patient that required surgical removal and aortic repair. CONCLUSIONS: Endovascular repair of traumatic aortic disruption can be accomplished in most cases. Compared with atherosclerotic aneurysms, the proximal thoracic aorta tends to be smaller and the arch angle tighter in an aorta 19mm in diameter. This frequently necessitates the use of smaller devices and less stiff wires. Surgeons should be prepared to cover the left subclavian artery if needed, have a wide range of device sizes in stock to avoid over-sizing, and show restraint if the anatomy appears unsuitable.  相似文献   
962.
A novel, potent series of indole analogs were recently developed as MR antagonists, culminating in 14. This compound represents the first MR antagonist in this class of molecules, exhibiting picomolar binding affinity and in vivo blood pressure lowering at pharmaceutically relevant doses.  相似文献   
963.
In the study reported here, we evaluated 2-screw femoral neck fixation. Femoral necks from 5 paired fresh-frozen cadavers were fractured and then fixed with two 7.3-mm cannulated cancellous screws. Vertical (parallel screws in sagittal plane of femoral neck) and horizontal (parallel screws in superior aspect of femoral neck) configurations were used for each matched pair. Mechanical testing was performed. Load, displacement, and stiffness at the yield point were significantly higher in the horizontal group, which also had a higher mean maximal failure load (P = .019). Preliminary data suggest that 2 horizontal screws in the superior aspect of the femoral neck provide more secure fixation than 2 vertical screws.  相似文献   
964.
Thoracic aorta disease remains a challenging problem, and despite improvements, open repair techniques are still associated with significant morbidity and mortality. This is a retrospective review of 53 consecutive patients with thoracic aortic pathology who were treated with endovascular repair between September 1998 and December 2004 at a tertiary-care hospital. Endovascular stent graft placement was performed on 23 elective and 30 emergent patients (34 male patients, mean age 66 years, 21 to 85 years). Completion angiography revealed no endoleak in 47 (89%) patients, a type I endoleak in 4 patients, and a type II endoleak in 2 patients. Operative 30-day mortality for elective aneurysms (n = 22), emergent aneurysms (n = 10), dissection (n = 3), penetrating aortic ulcers (n = 7), and trauma (n = 11) was 0%, 40%, 0%, 29%, and 9%, respectively. In total, 46 (87%) patients survived 30 days, and 36 (78.3%) of the survivors were discharged home free of complications. Two patients (4%) experienced paraplegia. Median follow-up was 22 months (1 to 72 months). Intermediate-term results revealed 41 (89%) patients free of endoleak, stent migration, or aneurysmal expansion. Two (4%) patients required reintervention with an additional stent graft. There were 2 (4%) patients with late aortic-related deaths and four (9%) patients with non-aorticrelated late deaths. Endovascular stent graft placement for thoracic aorta disease can be performed successfully and safely with good perioperative and intermediate-term outcomes. Stent graft complication and reintervention rates are low, whereas intermediate survival rates are good. Long-term efficacy still needs to be evaluated.  相似文献   
965.
The purpose of the present study was to determine whether an institution's prior endovascular experience influenced the learning curve of subsequent surgeons. A prospective analysis of the initial 70 endovascular abdominal aortic aneurysm repair (EVAR) cases attempted by an individual surgeon was performed with the primary outcome variable being achievement and 30-day maintenance of initial clinical success. Along with standard statistical analyses, the cumulative sum failure method (CUSUM) was used to analyze the learning curve, with a predetermined acceptable failure rate of 10%. Seventy elective EVAR cases were performed by this surgeon during a 4-year period (2000-2004) (mean age, 73.7 -/+ 5.4 years; mean aneurysm diameter 63.3 -/+ 7.2 mm). Initial clinical success was achieved in 68 of 70 cases (97%), which differed significantly with that of our initial surgeon (88.5%, P = .01). Causes of failure in the present series included 1 early mortality (1.4%) and 1 case of conversion to open repair with no instances of type I endoleak or endograft limb thrombosis. Both surgeons' cases were plotted sequentially with CUSUM curves revealing a significantly shorter learning curve for the second surgeon. Optimal results were achieved following 10 to 20 EVAR cases, as opposed to 60 cases in the initial series. Such an analysis confirms that as an institution's experience with EVAR increases, an individual surgeon's learning curve shortens considerably.  相似文献   
966.
STUDY DESIGN: Questionnaire study presented to practicing spine surgeons. OBJECTIVE: To evaluate surgeon preference and availability of selected electrophysiologic neuromonitoring for different spine surgeries. SUMMARY OF BACKGROUND DATA: Maximizing the safety of spinal procedures and limiting potential iatrogenic neurologic injury has made intraoperative neuromonitoring an attractive option. METHODS: We distributed a questionnaire to 180 orthopedic spine surgeons and neurosurgeons at a clinically oriented spine meeting asking surgeon preference and availability of various types of intraoperative neuromonitoring modalities for different types of surgical procedures. Demographic data were also gathered. RESULTS: Somatosensory evoked potentials (SSEPs) were the most available neuromonitoring modality, followed by electromyographies and motor-evoked potentials. In both anterior and posterior cervical surgery, SSEPs were the most preferred modality. MEPs were frequently preferred in myelopathic cervical cases. Almost 70% preferred some neuromonitoring for anterior thoracic/thoracolumbar cases and 55% for posterior thoracic/thoracolumbar cases. Surgeon satisfaction was related to the number of available neuromonitoring modalities. No significant differences were found between orthopedist and neurosurgeon preferences. Fellowship-trained surgeons were more likely to use neuromonitoring for specific indications. CONCLUSIONS: SSEPs remains the most widely available and preferred type of neuromonitoring for spine surgeons. The type of case and neurologic status of patient (eg, presence of myelopathy) affects these choices. Surgeons were more satisfied with greater neuromonitoring availability, and were more likely to use neuromonitoring if they had a fellowship background.  相似文献   
967.
A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether bronchoscopic or other minimal access approaches to the closure of bronchopleural fistulae (BPFs) were effective compared to a conventional re-thoracotomy. Our search identified 1052 abstracts, from which we identified six case series of greater than two post-pneumonectomy bronchopleural fistula patients. These series included reports of bronchial stenting, glue occlusion and scar obliteration of fistulae. No thoracoscopic techniques were reported except in case report form. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these papers are tabulated. We identified 85 post-pneumonectomy bronchopleural fistulae reported in the literature who underwent bronchoscopic procedures to attempt repair. There was a 30% cure rate using a range of bronchoscopic techniques in these series. Bronchoscopic techniques included cyanoacrylate or fibrin glue application, YAG laser therapy, injection of the vein sclerosant polidocanol and tracheo-bronchial stenting. The mortality was 40% in these patients reflecting the very high mortality with this complication. Many patients required multiple bronchoscopic procedures and also further drainage procedures of their empyemas. Bronchoscopic treatment has so far only been reported in small case series but may offer further treatment options in patients too unwell to undergo re-thoracotomy.  相似文献   
968.
Clinical studies with bortezomib have validated the proteasome as a therapeutic target for the treatment of multiple myeloma and non-Hodgkin's lymphoma. However, significant toxicities have restricted the intensity of bortezomib dosing. Here we describe the antitumor activity of PR-171, a novel epoxyketone-based irreversible proteasome inhibitor that is currently in clinical development. In comparison to bortezomib, PR-171 exhibits equal potency but greater selectivity for the chymotrypsin-like activity of the proteasome. In cell culture, PR-171 is more cytotoxic than bortezomib following brief treatments that mimic the in vivo pharmacokinetics of both molecules. Hematologic tumor cells exhibit the greatest sensitivity to brief exposure, whereas solid tumor cells and nontransformed cell types are less sensitive to such treatments. Cellular consequences of PR-171 treatment include the accumulation of proteasome substrates and induction of cell cycle arrest and/or apoptosis. Administration of PR-171 to animals results in the dose-dependent inhibition of the chymotrypsin-like proteasome activity in all tissues examined with the exception of the brain. PR-171 is well tolerated when administered for either 2 or 5 consecutive days at doses resulting in >80% proteasome inhibition in blood and most tissues. In human tumor xenograft models, PR-171 mediates an antitumor response that is both dose and schedule dependent. The antitumor efficacy of PR-171 delivered on 2 consecutive days is stronger than that of bortezomib administered on its clinical dosing schedule. These studies show the tolerability, efficacy, and dosing flexibility of PR-171 and provide validation for the clinical testing of PR-171 in the treatment of hematologic malignancies using dose-intensive schedules.  相似文献   
969.
970.
This study evaluated whether 333 seronegative African American female drug users (aged 18–59 years) participating in an HIV intervention and with higher levels of emotional distress, specifically symptoms of depression and anxiety, reduced HIV risk behaviors to a lesser extent than those with lower levels of emotional distress. Participants were recruited between June 1998 and January 2001 from inner-city Atlanta (Georgia, U.S.) neighborhoods and were randomly assigned to one of two enhanced gender-specific and culturally specific HIV intervention conditions or to the NIDA standard condition. Participants were interviewed at baseline, post-intervention and at 6-month follow-up with a structured questionnaire including information on sociodemographics, sexual and drug-using behavior, and psychosocial characteristics. Despite a significant decline in symptoms of emotional distress during the study period, the women in this sample reported high levels of depressive and anxiety symptoms at baseline and 6-month follow-up. Higher levels of emotional distress were positively associated with post-intervention sexual and drug-taking risk. Women in both enhanced intervention conditions reduced their sexual and drug-taking risks more than women in the standard intervention. Those in the motivation intervention arm experienced a greater reduction in depressive symptoms, accompanied by a greater reduction in sexual risk behavior. Findings suggest the need for effective interventions and mental health resources among subgroups of high-risk women who may be most resistant to behavioral change.  相似文献   
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