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31.
In the context of collateral circulation of the heart, the role of extra-cardiac collateral arteries has been thought to be negligible. We present a case in which such collateral vessel acted as a rescue, subsequent to a failed revascularisation attempt. With surgeons nowadays considering ‘less is more’ in terms of grafting in coronary artery bypass grafting (CABG), and more evidence arising in favour of medical therapy, we need to re-assess the role of these collateral vessels in the coronary circulation.  相似文献   
32.
Injury-related morbidity and mortality have been one of the most common causes of loss in productivity across all geographic distributions. It remains to be a global concern despite a continual improvement in regional and national safety policies. The establishment of trauma care systems and advancements in diagnostics and management have improved the overall survival of severely injured. A better understanding of the physiopathological and immunological responses to injury led to a significant shift in trauma care from “Early Total Care” to “Damage Control Orthopedics.” While most of these algorithms were tailored to the philosophy of “life before limb,” the impact of improper fracture management on disability and societal loss is increasingly being recognized. Recently, “Early Appropriate Care” of extremities has gained importance; however, its implementation is influenced by regional health care policies, available resources, and expertise and varies between low and high-income countries. A review of the literature was performed using PubMed, Embase, Web of Science, and Scopus databases on articles published from 1990 to 2020 using the Mesh terms “Polytrauma,” “Multiple Trauma,” and “Fractures.” This review aims to consolidate on guidelines and available evidence in the management of extremity injuries in a polytraumatized patient to achieve better clinical outcomes of these severely injured.  相似文献   
33.
PurposeWe examined the role of obesity and intraoperative red blood cell (RBC) and platelet transfusion in early allograft dysfunction (EAD) following liver transplantation (LT).MethodsThis is a retrospective analysis of 239 adult deceased-donor LT recipients over a 10-year period. EAD was defined by Olthoff’s criteria. Data collection included donor (D) and recipient (R) age, body mass index (BMI) ≥ 35 kg/m2, diabetes mellitus, allograft macrosteatosis, and intraoperative (RBC) and platelet administration. We employed logistic regression to evaluate associations of these factors with EAD. Results are presented as odds ratios (OR) and 95% confidence intervals (CI) with corresponding P values. A P ≤ .05 was considered statistically significant.ResultsEAD occurred in 85 recipients (36%). Macrosteatosis data were available for 199 donors. In the multivariate analyses, BMI-D ≥ 35 kg/m2 increased the odds of developing EAD by 156% in the entire cohort (OR 2.56, 95% CI 1.09-6.01) and by 187% in recipients with macrosteatosis data (n = 199, OR 2.87, 95% CI 1.15-7.15). Each unit of RBCs increased the odds for EAD by 8% (OR 1.08, 95% CI 1.02-1.14) and, for the subgroup of 238 recipients with macrosteatosis data, by 9% (OR 1.09, 95% CI 1.02-1.16).ConclusionWe found a significant independent association of donor obesity and intraoperative RBC transfusion with EAD but no such association for platelet administration, MELD score, age, recipient obesity, and diabetes.  相似文献   
34.
BACKGROUND CONTEXTThe indication to perform a fusion and decompression surgery as opposed to decompression alone for lumbar degenerative spondylolisthesis (LDS) remains controversial. A variety of factors are considered when deciding on whether to fuse, including patient demographics, radiographic parameters, and symptom presentation. Likely surgeon preference has an important influence as well.PURPOSEThe aim of this study was to assess factors associated with the decision of a Canadian academic spine surgeon to perform a fusion for LDS.STUDY DESIGN/SETTINGThis study is a retrospective analysis of patients prospectively enrolled in a multicenter Canadian study that was designed to evaluate the assessment and surgical management of LDS.PATIENT SAMPLEInclusion criteria were patients with: radiographic evidence of LDS and neurogenic claudication or radicular pain, undergoing posterior decompression alone or posterior decompression and fusion, performed in one of seven, participating academic centers from 2015 to 2019.OUTCOME MEASURESPatient demographics, patient-rated outcome measures (Oswestry Disability Index [ODI], numberical rating scale back pain and leg pain, SF-12), and imaging parameters were recorded in the Canadian Spine Outcomes Research Network (CSORN) database. Surgeon factors were retrieved by survey of each participating surgeon and then linked to their specific patients within the database.METHODSUnivariate analysis was used to compare patient characteristics, imaging measures, and surgeon variables between those that had a fusion and those that had decompression alone. Multivariate backward logistic regression was used to identify the best combination of factors associated with the decision to perform a fusion.RESULTSThis study includes 241 consecutively enrolled patients receiving surgery from 11 surgeons at 7 sites. Patients that had a fusion were younger (65.3±8.3 vs. 68.6±9.7 years, p=.012), had worse ODI scores (45.9±14.7 vs. 40.2±13.5, p=.007), a smaller average disc height (6.1±2.7 vs. 8.0±7.3 mm, p=.005), were more likely to have grade II spondylolisthesis (31% vs. 14%, p=.008), facet distraction (34% vs. 60%, p=.034), and a nonlordotic disc angle (26% vs. 17%, p=.038). The rate of fusion varied by individual surgeon and practice location (p<.001, respectively). Surgeons that were fellowship trained in Canada more frequently fused than those who fellowship trained outside of Canada (76% vs. 57%, p=.027). Surgeons on salary fused more frequently than surgeons remunerated by fee-for-service (80% vs. 64%, p=.004). In the multivariate analysis the clinical factors associated with an increased odds of fusion were decreasing age, decreasing disc height, and increasing ODI score; the radiographic factors were grade II spondylolisthesis and neutral or kyphotic standing disc type; and the surgeon factors were fellowship location, renumeration type and practice region. The odds of having a fusion surgery was more than two times greater for patients with a grade II spondylolisthesis or neutral and/or kyphotic standing disc type (opposed to lordotic standing disc type). Patients whose surgeon completed their fellowship in Canada, or whose surgeon was salaried (opposed to fee-for-service), or whose surgeon practiced in western Canada had twice the odds of having fusion surgery.CONCLUSIONSThe decision to perform a fusion in addition to decompression for LDS is multifactorial. Although patient and radiographic parameters are important in the decision-making process, multiple surgeon factors are associated with the preference of a Canadian spine surgeon to perform a fusion for LDS. Future work is necessary to decrease treatment variability between surgeons and help facilitate the implementation of evidence-based decision making.  相似文献   
35.
Fuchs PN  Roza C  Sora I  Uhl G  Raja SN 《Brain research》1999,821(2):480-486
Clinical and experimental observations suggest that opiates can exert different influences on the perception of stimuli from distinct sensory modalities. Thermally-induced nociception is classically responsive to opiate agonists. mu-Opioid receptor-deficient transgenic mice are more sensitive to thermal nociceptive stimuli and morphine fails to attenuate the nociceptive responses to thermal stimuli in these animals. To enhance our understanding of opiate influences on mechanical sensitivity, we have examined withdrawal responses to a sequence of ascending forces of mechanical stimuli in mice with normal (wild type), half-normal (heterozygous) and absent (homozygous) mu-opioid receptor levels. We report data from mice examined without drug pretreatment or following pretreatment with morphine, the selective kappa-opioid agonist, U50488H, and the selective delta-opioid agonist, DPDPE. Saline-pretreated mice of each genotype displayed similar, monotonically increasing frequency of withdrawal responses to the graded stimuli. Subcutaneously administered morphine produced a dose-dependent reduction in withdrawal responses in wild type and heterozygous mice, but had no significant effect in homozygous mice. Intraventricular administration of DPDPE also reduced the frequency of paw withdrawal (FPW) in wild type mice, but not in homozygous mice. In contrast, systemic U50488H produced a dose-dependent attenuation of paw withdrawal in both wild type and homozygous mice. These findings suggest that (1) interactions of endogenous peptides with mu-opioid receptors may not play a significant role in the response to mechanical stimuli in drug-free animals, and (2) deficiency of mu-opioid receptors has no functional consequence on the response to the prototypical kappa-opioid receptor agonist, but decreases responses to the prototypical mu- and delta-opioid receptor agonists.  相似文献   
36.
AIM: Thoracic outlet syndrome (TOS) is a clinical diagnosis treatable by excision of the first rib. This study was undertaken to assess the alleviation of symptoms following trans-axillary rib excision in patients with a diagnosis of TOS suggested by a positive Elevated Arm Stress Test and, by inference, to estimate the prevalence of the syndrome. METHOD: A retrospective review of trans-axillary first rib excision was performed. No referrals were accepted from outwith the catchment area of our hospital. Post-operative symptomatic improvement was accepted as a confirmation of correct pre-operative diagnosis. RESULTS: Over six years, 52 rib resections were performed in 46 patients, mean age (+/- S.D.) 38.8 (+/- 10.6) years. The indications for surgery were principally neurological symptoms (n = 42 excisions), arterial compromise (n = 5) and venous compromise (n = 5). Symptoms had been present for a mean of 15.8 months prior to surgery. The median follow-up after surgery was 33 months. 42 patients (48 resections) showed immediate improvement in symptoms following surgery, although symptoms recurred in three patients (4 resections) between 6 and 8 months post-operatively. In the final two years of this study, 20 resections resulting in symptomatic improvement were performed, suggesting a prevalence for TOS of at least 10 per 100,000 per year. CONCLUSIONS: Thoracic outlet decompression was performed more frequently in this series than many previous reports, suggesting that TOS may be under-diagnosed.  相似文献   
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Epithelioid hemangioma (EH) is a rare benign vascular tumor that occurs in soft tissues and bone and presents between the third and sixth decades of life. Little is known about the clinical course and outcomes of pediatric EH. We report 11 patients diagnosed with EH at a median age of 14.4 years. One patient treated with interferon and one with sirolimus exhibited partial response for >2 years. Although a benign neoplasm, EH is difficult to manage without standard protocols and portends considerable morbidity. Our findings suggest medical management, particularly sirolimus, may benefit these patients; however, long‐term follow‐up is needed.  相似文献   
40.
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