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81.
82.
Background contextThoracolumbar burst fractures have good outcomes when treated with early ambulation and orthosis (TLSO). If equally good outcomes could be achieved with early ambulation and no brace, resource utilization would be decreased, especially in developing countries where prolonged bed rest is the default option because bracing is not available or affordable.PurposeTo determine whether TLSO is equivalent to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures with respect to their functional outcome at 3 months.Study designA multicentre, randomized, nonblinded equivalence trial involving three Canadian tertiary spine centers. Enrollment began in 2002 and 2-year follow-up was completed in 2011.Patient sampleInclusion criteria included AO-A3 burst fractures between T11 and L3, skeletally mature and older than 60 years, 72 hours from their injury, kyphotic deformity lower than 35°, no neurologic deficit. One hundred ten patients were assessed for eligibility for the study; 14 patients were not recruited because they resided outside the country (3), refused participation (8), or were not consented before independent ambulation (3).Outcome measuresRoland Morris Disability Questionnaire score (RMDQ) assessed at 3 months postinjury. The equivalence margin was set at δ=5 points.MethodsThe NO group was encouraged to ambulate immediately with bending restrictions for 8 weeks. The TLSO group ambulated when the brace was available and weaned from the brace after 8 to 10 weeks. The following competitive grants supported this work: VHHSC Interdisciplinary Research Grant, Zimmer/University of British Columbia Research Fund, and Hip Hip Hooray Research Grant. Aspen Medical provided the TLSOs used in this study. The authors have no financial or personal relationships that could inappropriately influence this work.ResultsForty-seven patients were enrolled into the TLSO group and 49 patients into the NO group. Forty-six participants per group were available for the primary outcome. The RMDQ score at 3 months postinjury was 6.8±5.4 (standard deviation [SD]) for the TLSO group and 7.7±6.0 (SD) in the NO group. The 95% confidence interval (?1.5 to 3.2) was within the predetermined margin of equivalence. Six patients required surgical stabilization, five of them before initial discharge.ConclusionsTreating these fractures using early ambulation without a brace avoids the cost and patient deconditioning associated with a brace and complications and costs associated with long-term bed rest if a TLSO or body cast is not available.  相似文献   
83.
Pediatric heart allocation in Eurotransplant (ET) has evolved over the past decades to better serve patients and improve utilization. Pediatric heart transplants (HT) account for 6% of the annual transplant volume in ET. Death rates on the pediatric heart transplant waiting list have decreased over the years, from 25% in 1997 to 18% in 2011. Within the first year after listing, 32% of all infants (<12 months), 20% of all children aged 1–10 years, and 15% of all children aged 11–15 years died without having received a heart transplant. Survival after transplantation improved over the years, and in almost a decade, the 1‐year survival went from 83% to 89%, and the 3‐year rates increased from 81% to 85%. Improved medical management of heart failure patients and the availability of mechanical support for children have significantly improved the prospects for children on the heart transplant waiting list.  相似文献   
84.
ObjectiveAlthough most patients with urinary bladder cancer present with noninvasive and low-malignant stages of the disease, about 20% eventually develop life-threatening metastatic tumors. This study was designed to evaluate the potential of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) to identify molecular markers predicting the clinical course of bladder cancer.Materials and methodsWe employed MALDI-MSI to a bladder cancer tissue microarray including paraffin-embedded tissue samples from 697 patients with clinical follow-up data to search for prognostically relevant associations.ResultsAnalysis of our MALDI imaging data revealed 40 signals in the mass spectra (m/z signals) associated with epithelial structures. The presence of numerous m/z signals was statistically related to one or several phenotypical findings including tumor aggressiveness (stage, grade, or nodal status; 30 signals), solid (5 signals) or papillary (3 signals) growth patterns, and increased (6 signals) or decreased (12 signals) cell proliferation, as determined by Ki-67 immunohistochemistry. Two signals were linked with tumor recurrence in noninvasive (pTa category) tumors, of which one was also related to progression from pTa-category to pT1-category disease. The absence of one m/z signal was linked with decreased survival in the subset of 102 muscle-invasive cancers.ConclusionOur data demonstrate the suitability of combining MSI and large-scale tissue microarrays to simultaneously identify and validate clinically useful molecular markers in urinary bladder cancer.  相似文献   
85.

Background

A microscopically irradical (R1) resection is a well-known adverse prognostic factor after gastric cancer surgery. However, the prognostic significance of an R1 resection in gastric cancer patients who are treated with chemoradiotherapy (CRT) after the operation has been poorly studied. Therefore, the aim of this study was to evaluate the effect of an R1 resection on (recurrence-free) survival in gastric cancer patients who were treated with CRT after surgery.

Methods

Gastric cancer patients who had undergone a resection with curative intent followed by adjuvant CRT at our institute between 2001 and 2011 were included. CRT consisted of radiotherapy (45 Gy/25 fractions) combined with concurrent capecitabine (with or without cisplatin) or 5-fluorouracil/leucovorin.

Results

A consecutive series of 110 patients was studied, including 80 (73 %) patients who had undergone an R0 resection and 30 (27 %) patients with an R1 resection. Pathologic T-classification (p = 0.26), N-classification (p = 0.77), and histologic subtype according to Laurén (p = 0.071) were not significantly different between these groups. Three-year recurrence-free survival (45 vs. 35 %, p = 0.34) and overall survival (47 vs. 48 %, p = 0.58) did not significantly differ between patients who had undergone an R0 or R1 resection. In a multivariate analysis, pathologic T-classification and N-classification were independent prognostic factors for survival.

Conclusions

A R1 resection was not an adverse prognostic factor in gastric cancer patients who had undergone CRT after the operation.  相似文献   
86.
Bisphosphonate use has declined dramatically in recent years, partly because of fear of rare side effects like atypical femur fractures (AFFs). It is therefore desirable to have a diagnostic method to identify those at risk of AFF to prevent this serious complication. We compared trabecular microarchitecture and hip geometry between 30 patients with AFF and 141 controls of similar age and sex, using bisphosphonates. Trabecular bone score (TBS) and hip structural analysis (HSA) were used to assess trabecular microarchitecture and macroscopic hip geometry from dual-energy X-ray absorptiometry images of the lumbar spine and hip, respectively. General characteristics, TBS, and HSA were compared between patients with AFF and controls using Student's t tests and chi-square statistics. Associations between AFF and TBS and femur geometric characteristics by HSA were adjusted for sex, age, height, weight, ethnicity, duration of bisphosphonate use, and glucocorticoid use. Additionally, the analysis of TBS was adjusted for lumbar spine bone mineral density and the time difference between dual-energy X-ray absorptiometry scanning and the diagnosis of AFF. Patients with AFF had significantly higher body mass index than controls, had used bisphosphonates longer, and glucocorticoids and proton pump inhibitors more frequently. Sex-specific T-score was significantly higher in patients with AFF at the lumbar spine (p?=?0.004), but not at the femoral neck (p?=?0.190) after adjustment for age, height, and weight. TBS did not differ significantly between patients with AFF and controls. Neither neck shaft angle nor any geometric variables at the femoral shaft measured by HSA differed between patients with AFF and controls. At the narrow neck, patients with AFF had lower buckling ratio and higher centroid position, consistent with a lower risk of classical fragility hip fractures. The findings at narrow neck and higher bone mineral density might be explained by the fact that the majority of patients with AFF used bisphosphonates to prevent glucocorticoid-induced osteoporosis. Based on our results, TBS and HSA do not appear to have value in detecting patients at risk of AFF.  相似文献   
87.
BACKGROUND: Comparison of outcome of untunnelled catheters (UCs) and tunnelled cuffed catheters (TCCs) is difficult because they are usually used for different patients and conditions. The aim of the present study is to compare the outcome of TCCs with UCs limiting as much as possible the influence of confounding factors. The second purpose was to see whether our results support the time recommendations for maximum use of UCs outlined in the NKF-DOQI guidelines. METHODS: Catheter and patient characteristics, catheter-related complications and all cultures taken from haemodialysis catheters inserted during a 3 year period were collected. RESULTS: We analysed the outcome of 272 catheters (149 patients, 11 612 catheter-days, 37 TCC and 235 UC). Patients with an UC suffered more often from acute renal failure (40 vs 8% for TCCs, P<0.001), their hospitalization rates were higher (54 vs 14%, P<0.001) and coumarins were used less (11 vs 27%, P<0.01). Rates of preliminary removal were 1.8 per 1000 catheter-days for TCCs, 35.3 for untunnelled femoral catheters (UFCs) and 17.1 for untunnelled jugular catheters (UJCs). Infection rates were 2.9 per 1000 catheter-days for TCCs, 15.6 for UJCs and 20.2 for UFCs. Hospitalization was an independent risk factor for an adverse outcome and more apparent in patients with an UC. After correction for patient differences, the strongest risk factor for preliminary removal (RR 9.69, P<0.001) and infection (RR 3.76, P<0.001) was having an UC inserted. Already, within 2 weeks actuarial and infection-free survival were better for TCCs (P<0.05 vs all separate groups). CONCLUSIONS: According to our results, a TCC should be used whenever it can be foreseen that a haemodialysis catheter is needed for more than 14 days.  相似文献   
88.
Ca-activated Cl currents (I(Cl(Ca))) are used frequently as reporters in functional studies of anesthetic effects on G protein-coupled receptors using Xenopus laevis oocytes. However, because anesthetics affect protein kinase C (PKC), they could indirectly affect I(Cl(Ca)) if this current is regulated by phosphorylation. We therefore studied the effect of modulation of either PKC or protein phosphatases PP1alpha and PP2A on I(Cl(Ca)) stimulated either by lysophosphatidate (LPA) signaling or by microinjection of Ca. X. laevis oocytes were studied under voltage clamp. Rat PP1alpha and PP2A were overexpressed in oocytes. PP, inositoltrisphosphate (IP(3)), the PP inhibitor okadaic acid (OA), the PKC inhibitor chelerythrine, or CaCl(2) were directly injected into the oocyte. Responses to agonists (LPA 10(-6) M, IP(3) 10(-4) M, CaCl(2) 0.5 M) were measured at a holding potential of -70 mV in the presence or absence of the PP inhibitors cantharidin or OA. PP1 alpha and PP2A inhibited I(Cl(Ca)) from 7.6 +/- 0.9 microC to 2.5 +/- 0.9 microC and 3.2 +/- 1.4 microC, respectively. PP inhibition enhanced I(Cl(Ca)) in control oocytes and reversed the inhibitory effect in oocytes expressing PP1 alpha or PP2A. PKC inhibition by chelerythrine enhanced both LPA- and CaCl(2)-induced I(Cl(Ca)). Our data indicate that the Xenopus I(Cl(Ca)) is modulated by phosphorylation. This may complicate design and interpretation of studies of G protein-coupled receptors using this model.  相似文献   
89.
The cardiovascular actions of the synthetic natriuretic peptide, atriopeptin II, were examined in conscious unrestrained spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. The animals were chronically instrumented with miniaturized pulsed Doppler flow probes to allow measurement of regional blood flow, or with an electromagnetic flow probe on the ascending aorta to facilitate the measurement of cardiac output in the conscious rat. Intravenous infusion of increasing doses of atriopeptin II (0.25-4 micrograms/kg per min) caused a dose-dependent fall in mean arterial pressure in the hypertensive and normotensive rats. Blood flow in the renal, mesenteric, and hindquarters vascular beds was markedly decreased during the infusion of atriopeptin II, and regional vascular resistance was significantly increased in both groups of rats. Heart rate was significantly elevated (47 +/- 14 beats/min) in the spontaneously hypertensive rats during atriopeptin II infusion, but no change in heart rate was observed in the Wistar rats. In the hypertensive rats, atriopeptin II caused a marked dose-dependent decrease in cardiac output (maximal decrease = -39 +/- 4%) and stroke volume (maximal decrease = -48 +/- 4%). Central venous pressure and left atrial pressure were also significantly reduced during atriopeptin II infusion. Total peripheral resistance was increased over the infusion protocol by 26 +/- 3%. These data suggest that atriopeptin II infusion markedly attenuated cardiac output in the conscious spontaneously hypertensive rats. Total and regional vascular resistances were increased, possibly through reflex compensatory mechanisms, to maintain arterial pressure in the face of decreased cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
90.
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