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Extradural sacral (caudal) block was performed in 17 cases (14 patients) of chronic low back pain. In each case 22 ml of a bupivacaine/methylprednisolone solution incorporating a radioopaque dye was injected over a 2-min period. Patients were randomly assigned to receive the injection in the horizontal position or with 15 degrees head-up or head-down tilt applied to the operating table. Results indicate that analgesia is usually more localised than spread of solution determined by x-ray evidence and that higher levels of analgesia are achieved in patients in the head-up position. Possible causes are the differing distribution characteristics of the constituents of the solution and the gravitational effects of posture on cerebrospinal fluid mechanics. Technical problems associated with obesity, congenital abnormalities, vascular uptake of solution, and delayed spread of the injectant due to adhesions are discussed.  相似文献   
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Reductions in serum levels of Gc globulin, a hepatically synthesized component of the extracellular actin scavenger system responsible for complexing circulating actin and attenuating intravascular microthrombus formation, are associated with poor outcome in acute liver failure. Clinically applicable assays of the important actin-free fraction (Af-Gc) have not been available until now. We measured actin-free Gc globulin levels with a novel, rapid assay in 61 cases of acute liver failure (ALF) and in 91 patients with cirrhosis (40 of whom were clinically unstable with extrahepatic organ dysfunction), and studied associations with liver dysfunction, extrahepatic organ dysfunction, indices of disseminated coagulation, and outcome. Reductions in Af-Gc levels mirrored hepatic dysfunction and organ dysfunction in both groups, and discriminated patients with poor prognosis from those with good prognosis in the ALF cohort. Levels were lowest in patients with ALF (10% of control values), but levels were also markedly reduced in both unstable (28%) and stable (44%) patients with cirrhosis. Associations with markers of disseminated intravascular coagulation were seen in both groups, most notably in the cirrhosis cohort, supporting a pathophysiological role for reduced Af-Gc in the evolution of organ dysfunction. In acetaminophen-induced ALF, Af-Gc identified patients with poor prognosis as well as did the Acute Physiology and Chronic Health Evaluation (APACHE II) score (area under the receiver operating characteristic curve, 0.7), and in cirrhosis, Af-Gc was an independent predictor of mortality by multifactorial analysis. In conclusion, the importance of Af-Gc reductions in the development of multiple organ dysfunction in ALF and cirrhosis is highlighted, probably resulting from reduced hepatic production and peripheral exhaustion of this arm of the extracellular actin scavenger system.  相似文献   
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Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. INTRODUCTION: Since FDA approval of PTH [PTH(1-34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. MATERIALS AND METHODS: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 microg/kg PTH(1-34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. RESULTS: Quantitative muCT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized beta-catenin protein, a central feature of canonical Wnt signaling. CONCLUSIONS: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways.  相似文献   
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Recent research suggests that, for some people with severe mental illness, supported employment could improve vocational outcomes for little additional expense. This study describes the costs and client outcomes in one mental health center that converted two rehabilitative day treatment programs to supported employment. Converting from day treatment to supported employment improved vocational outcomes significantly without increasing costs. Although total costs for community treatment were lower in both sites after implementing supported employment, differences appeared to be due to decreasing unit costs over the study period. Results illustrate the importance of testing the effects of cost estimation methods on findings.This study was supported by West Central Services, the New Hampshire Division of Mental Health and Developmental Services, and NIMH grant K02-MH-00839. The authors are grateful to Jesse Turner and Phil Wyzik for facilitating the research.  相似文献   
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