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41.
42.

Background

A growing body of published research on tranexamic acid (TXA) suggests that it is effective in reducing blood loss and the risk for transfusion in total knee arthroplasty (TKA). The purpose of this network meta-analysis was to evaluate TXA in primary TKA as the basis for the efficacy recommendations of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Medicine on the use of TXA in primary total joint arthroplasty.

Methods

We searched Ovid MEDLINE, Embase, Cochrane Reviews, Scopus, and Web of Science databases for publications before July 2017 on TXA in primary total joint arthroplasty. All included studies underwent qualitative and quantitative homogeneity testing. Direct and indirect comparisons were performed as a network meta-analysis, and results were tested for consistency.

Results

After critical appraisal of the available 2113 publications, 67 articles were identified as representing the best available evidence. Topical, intravenous (IV), and oral TXA formulations were all superior to placebo in terms of decreasing blood loss and risk of transfusion, while no formulation was clearly superior. Use of repeat IV and oral TXA dosing and higher doses of IV and topical TXA did not significantly reduce blood loss or risk of transfusion. Preincision administration of IV TXA had inconsistent findings with a reduced risk of transfusion but no effect on volume of blood loss.

Conclusions

Strong evidence supports the efficacy of TXA to decrease blood loss and the risk of transfusion after primary TKA. No TXA formulation, dosage, or number of doses provided clearly improved blood-sparing properties for TKA. Moderate evidence supports preincision administration of IV TXA to improve efficacy.  相似文献   
43.
A novel method of quantitating cell migration has been proposed for the potential utilization of tissue engineered scaffolds. Applying Alt's conservation law to describe the motion of first passage ACL and MCL cells, we have developed a quantitative method to assess innate differences in the motility of cells from these two ligamentous tissues. In this study, first passage ACL and MCL cells were cultured from four mature New Zealand white rabbits. One side of the cell monolayer was scraped completely away to create a wound model. The cell moved into the cell-free area, and cell density profiles were analyzed at 6 h and 12 h. Values of the random motility coefficient (mu) were then estimated by curve fitting the 6 h and 12 h data to a mathematical model, derived from the conservation law of cell flux. During 6 h of incubation in medium supplemented with 1% FBS, MCL cells (mu(MCL) = 4.63 +/- 0.65 X 10(-6) mm(2)/sec) were significantly (p < 0.05) more mobile than ACL cells (mu(ACL) = 2.51 +/- 0.31 X 10(-6) mm(2)/sec). At 12 h, the MCL cells also appeared to move faster (mu(ACL) = 4.39 +/- 0.63 X 10(-6) mm(2)/sec, mu(MCL) = 6.59 +/- 1.47 X 10(-6) mm(2)/sec), but the difference was not statistically significant (p = 0.18). Exposure of the cells to growth factors PDGF-BB or bFGF for 6 h had no significant effect on the migration of the ACL and MCL cells. However, exposure of the ACL cells (p < 0.05) and the MCL cells (p = 0.19) to 1 ng/mL of PDGFBB for 12 h enhanced their migration. Incubation with a high concentration (100 ng/mL) of PDGF-BB or bFGF at concentrations tested (1 or 100 ng/mL) for 12 h, produced little or no migratory stimulation on these ligament cells. Our findings support the previous qualitative observations made by numerous investigators. The novel methodology developed in this study may provide a basis for tissue engineering, and the results may be applied to tissue reconstruction techniques of the knee ligaments.  相似文献   
44.
Background/aims: Early repeat endoscopic retrograde cholangiopancreatography may be required due to various conditions in patients who underwent planned endoscopic retrograde cholangiopancreatography. We aimed to assess the factors leading to early repeat endoscopic retrograde cholangiopancreatography and to determine the patients who need closer follow-up. Materials and Methods: A total of 691 patients with a mean age of 60.3±16.4 years who had naive papilla on endoscopic retrograde cholangiopancreatography were involved in the study. The patients who required repeat endoscopic retrograde cholangiopancreatography were identified. Presentations, predictive factors, treatment modalities, and outcomes of the patients were investigated. Results: Early repeat endoscopic retrograde cholangiopancreatography was needed in 19 (2.7%) patients. The most common presentation was cholangitis in 10 (52.6%) and unresolved jaundice in 4 (21.1%). Multivariate analysis identified biliary stricture (p=0.024), stricture at the hilus (p=0.005) and unilateral drainage in the presence of hilar stricture (p=0.017) as the independent risk factors for early repeat endoscopic retrograde cholangiopancreatography. Stent migration or dysfunction was the most common underlying cause. Therapeutic interventions were nasobiliary drainage in 13, stent exchange in 4 and stone removal in 2. Additionally, percutaneous drainage in 4 patients, drainage of abscess in 2 patients and percutaneous drainage of gallbladder in 1 patient were performed. Three patients died due to their underlying illness. Conclusions: Unilateral stenting especially in hilar strictures is a predictive factor for early repeat endoscopic retrograde cholangiopancreatography with high mortality. These patients should be under close follow-up.  相似文献   
45.
In many neurons, trains of action potentials show frequency-dependent broadening. This broadening results from the voltage-dependent inactivation of K+ currents that contribute to action potential repolarisation. In different neuronal cell types these K+ currents have been shown to be either slowly inactivating delayed rectifier type currents or rapidly inactivating A-type voltage-gated K+ currents. Recent findings show that inactivation of a Ca2+-dependent K+ current, mediated by large conductance BK-type channels, also contributes to spike broadening. Here, using whole-cell recordings in acute slices, we examine spike broadening in lateral amygdala projection neurons. Spike broadening is frequency dependent and is reversed by brief hyperpolarisations. This broadening is reduced by blockade of voltage-gated Ca2+ channels and BK channels. In contrast, broadening is not blocked by high concentrations of 4-aminopyridine (4-AP) or α-dendrotoxin. We conclude that while inactivation of BK-type Ca2+-activated K+ channels contributes to spike broadening in lateral amygdala neurons, inactivation of another as yet unidentified outward current also plays a role.  相似文献   
46.
Neurotransmitter modulation of calcium current in rat spinal cord neurons   总被引:5,自引:0,他引:5  
The modulation of Ca2+ currents by neurotransmitters was studied in freshly dissociated rat spinal cord neurons, using the whole-cell patch-clamp technique. GABA, baclofen, adenosine, ATP, serotonin, norepinephrine, somatostatin, and dynorphin A inhibited the current through Ca2+ channels in a substantial fraction of cells, while substance P, vasoactive intestinal polypeptide, [D-ala2,d-leu5]-enkephalin, cholecystokinin-8 (sulfated), calcitonin gene-related peptide, angiotensin II, neurotensin, vasopressin, and thyrotropin-releasing hormone had no effect. In the case of baclofen, the inhibition is mediated, at least in part, by a GTP-binding protein. Suppression of Ca2+ current by neurotransmitters may represent a mechanism of presynaptic inhibition in the spinal cord.  相似文献   
47.
48.
BACKGROUND: Dental caries remains the most important dental health problem in developing countries. In India the prevalence of dental caries is reported to be about 50-60%. Most of the Indian studies have been carried out in school children and very few in adults. This study aimed to estimate the prevalence of dental caries in the adult population (aged 35-44 years) and in the elderly (60 years and above) in an urban resettlement colony in New Delhi. METHODOLOGY: A community-based cross-sectional study was carried out in Dakshinpuri, New Delhi, from January to February 2007. A local adaptation of the WHO questionnaire was used. Oral examination was done and dentition status was recorded by trained investigators and according to the standard procedures. RESULTS: A total of 452 participants were enrolled in the study. The prevalence of dental caries in the 35-44 years age-group was 82.4% and it was 91.9% in those > or =60 years. The DMF index was 5.7 +/- 4.7 in the 35-44 years age-group and 13.8 +/- 9.6 in the > or =60 years age-group. Of the participants, 27.9% were currently using tobacco. A statistically significant association was found between tobacco consumption and dental caries ( P = 0.026). The awareness about good and bad dental practices was found to be low among the study participants. One-fifth of the individuals with dental problems relied on home remedies. CONCLUSION: The prevalence of dental caries among adults is high in this population. There is a need to generate awareness about oral health and the prevention of dental caries and to institute measures for the provision of dental care services at the primary level.  相似文献   
49.
The purpose of this study was to compare the total epidural dose of 3 commonly used labor epidural modalities. After local institutional review board approval, 195 laboring parturients received an epidural catheter for labor analgesia. All patients received an initial bolus of 0.1% ropivacaine (10 mL) and fentanyl (100 microg). Maintenance of labor analgesia consisted of ropivacaine 0.1% with fentanyl 2 microg/mL. Patients were then randomly assigned into 3 groups: Group 1 (continuous epidural infusion [CEI]), continuous infusion at 10 mL/h; group 2 (CEI + patient-controlled epidural analgesia [PCEA]), CEI at 5 mL/h with a demand dose of 5 mL allowed every 20 minutes with a 20 mL/h maximum dose; group 3 (PCEA), demand doses only of 5 mL every 15 minutes with a 20 mL/h maximum dose. Measured variables included total epidural dose, total bolus requests and boluses delivered, number of staff interventions, pain Visual Analog Scale (VAS; 0-100), modified Bromage scores, stage I and II labor duration, delivery outcome, and maternal satisfaction after delivery. No differences were noted with respect to pain VAS, modified Bromage scores, stage I and II labor duration, number of staff interventions, delivery outcome, and maternal satisfaction score. Total infusion dose was lower in demand dose only PCEA compared with CEI and CEI + PCEA groups (P = < .01). Demand dose-only PCEA results in less total epidural dose compared with CEI and CEI + PCEA without affecting labor duration, motor block, pain VAS, maternal and neonatal outcomes, and maternal satisfaction. PERSPECTIVE: This article compares 3 commonly used labor epidural delivery modalities (traditional continuous epidural infusion, patient-controlled epidural analgesia with a background infusion, and demand dose-only patient-controlled epidural analgesia). Benefits in epidural dose reduction with demand dose only PCEA does not translate into improved maternal and neonatal outcome.  相似文献   
50.
T cell–replete post-transplant cyclophosphamide (PTCy)-based protocols have led to increasing use of haploidentical allogeneic hematopoietic cell transplantation (haploHCT). With this approach, bidirectional alloreactivity causing nonengraftment or severe graft-versus-host disease (GVHD) is no a longer major barrier to haploHCT. PTCy eliminates alloreactive lymphocytes but spares CD34+ stem cells and regulatory T lymphocytes, resulting in reliable hematopoietic recovery with relatively low incidence of GVHD. The immediate post-haploHCT course, usually before PTCy administration, is often complicated by cytokine release syndrome (CRS). The predictors of CRS and its effect on outcomes post-transplant have not been fully ascertained. We analyzed the outcomes of 66 patients who received haploHCT at our institution. Using published CRS criteria we identified 48 patients who developed CRS. In multivariate analysis peripheral blood grafts were significantly associated with grade ≥ 2 CRS, compared with bone marrow. Grade ≥ 2 CRS (compared with grade < 2) was not associated with differences in overall survival or nonrelapse mortality. Severe CRS was associated with a statistically nonsignificant trend toward higher incidences of grades III to IV acute GVHD, especially in the context of peripheral blood grafts. CRS is a common complication after T cell–replete peripheral blood haploHCT, but post-transplant survival outcomes may not be affected in those with severe CRS.  相似文献   
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