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51.
该文旨在介绍Beth Israel医疗中心采用大剂量术中放疗(HDR-IORT)治疗复发头颈癌的经验。对2001-2010年间头颈癌局部复发接受大剂量HDR-IORT的患者进行回顾分析。结果,76例患者的87个部位在肿瘤切除后接受了治疗。术后2年控制率为62%。平均总生存期为19个月,其中42%的患 相似文献
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Nugent NR Ostrowski S Christopher NC Delahanty DL 《Journal of pediatric psychology》2007,32(3):309-318
OBJECTIVE: To examine how parental responses following pediatric injury may influence their child's posttraumatic stress symptoms (PTSS). METHODS: Heart rate (HR) from 82 pediatric injury patients was measured during emergency medical services (EMSs) transport and following hospital admission. Twelve-hour urinary cortisol levels were assessed upon admission. Child PTSS and parental PTSS and general distress were assessed 6 weeks and 6 months after trauma. RESULTS: Six-week parental PTSS predicted 6-month child PTSS even after controlling for demographics and general parent distress (DeltaR(2) = .08, p = .03). Parental PTSS moderated the relationship between (a) child cortisol levels and 6-month child PTSS (DeltaR2 = .08, p = .03) and between (b) hospital HR and 6-month child PTSS (DeltaR2 = .09, p = .03). CONCLUSION: The present findings suggest that parental response to trauma may interact with child acute physiological responses to predict persistent child PTSS. 相似文献
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Kim D Harrison Beverly D Hiebert Arash Panahifar Janna M Andronowski Amir M Ashique Gavin A King Terra Arnason Kurtis J Swekla Peter Pivonka David ML Cooper 《Journal of bone and mineral research》2020,35(11):2211-2228
Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).. 相似文献
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A small region of the beta-adrenergic receptor is selectively involved in its rapid regulation. 总被引:7,自引:3,他引:7
W P Hausdorff P T Campbell J Ostrowski S S Yu M G Caron R J Lefkowitz 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(8):2979-2983
Plasma membrane receptors that couple to guanine nucleotide-binding regulatory proteins (G proteins) undergo a variety of rapid (minutes) and longer term (hours) regulatory processes induced by ligands. For the beta 2-adrenergic receptor (beta 2AR), the rapid processes include functional desensitization, mediated by phosphorylation of the receptor by the cAMP-dependent protein kinase and the beta-adrenergic receptor kinase, as well as a loss of hydrophilic ligand binding proposed to represent sequestration of receptors into a cellular compartment distinct from the plasma membrane. The slower processes include beta 2AR down-regulation (i.e., a decrease in the total cellular complement of receptors). It is not yet known whether beta 2AR phosphorylation and/or sequestration are prerequisites for down-regulation of the receptor. Like other G protein-coupled receptors, the beta 2AR molecule spans the plasma membrane seven times, and the cytoplasmic carboxyl-terminal domain has been proposed to contain molecular determinants for each of these regulatory processes. We replaced four serine and threonine residues located within a 10-amino acid segment of this domain of beta 2AR and thereby prevented agonist-promoted phosphorylation, sequestration, and rapid desensitization of the adenylyl cyclase response. In contrast, these mutations did not affect functional coupling to the stimulatory G protein Gs or long-term down-regulation. These findings thus define a small, hitherto unappreciated region of the receptor molecule that may selectively subserve its rapid regulation. In addition, with the demonstration that beta 2AR does not have to be phosphorylated or sequestered in order to enter the down-regulation pathway, the results suggest that the classical receptor endocytosis model may not be appropriate for beta 2AR regulation. 相似文献
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Auber ML; Horwitz LJ; Blaauw A; Khorana S; Tucker S; Woods T; Warmuth M; Dicke KA; McCredie KB; Spitzer G 《Blood》1988,71(1):166-172
Relatively nonmyelotoxic drugs and drug combinations were investigated for their ability to eliminate malignant cells from human bone marrow. In vitro 90% inhibitory concentration (IC90) doses were established on granulocyte macrophage colony-forming units (GM-CFU) in culture of bone marrow by using the GM-CFU assay for the following drugs: 4- hydroperoxycyclophosphamide (4-HC), Adriamycin, L-asparaginase, bleomycin, hydrocortisone, VP-16, spirogermanium, Taxol, and vincristine. The leukemic cell kill efficiency of these drugs at IC90 doses was compared with that of 4-HC on acute lymphoid leukemia (ALL) cell lines by using the limiting-dilution assay. Under these conditions, no single drug was superior to 4-HC. To increase the in vitro effect in leukemic cell kill, combinations of vincristine with hydrocortisone, Adriamycin, VP-16, and 4-HC were investigated. Vincristine at 1 to 5 micrograms/mL increased the marrow cytotoxicity of hydrocortisone, Adriamycin, and VP-16, but it was protective (subadditive) with 4-HC. Vincristine and 4-HC in combination was additive to supraadditive on ALL cell lines, increased the leukemic cell kill by one to two logs above 4-HC alone at IC90 doses (P less than .05), and was not affected by the addition of excess marrow cells. The recommended doses for chemopurging in clinical studies are vincristine, 1 to 5 micrograms/mL, plus 4-HC, 5 micrograms/mL. 相似文献
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Eske K. Aasvang Sandra Pitter Carsten P. Hansen Jan H. Storkholm Paul S. Krohn Stefan K. Burgdorf Jakob H. Von Stemann Jens D. Lundgren Susanne D. Nielsen Henrik Kehlet Sisse R. Ostrowski 《Scandinavian journal of immunology》2020,92(3):e12930
Major surgery is associated with substantial morbidity and mortality with early post-operative adverse events (POAE) occurring in 30% of patients within the first 30 days. The underlying pathogenesis is multifactorial, including immune dysfunction and increased inflammatory response to surgery. We investigated preoperative immune function by the TruCulture® whole blood technique in a cohort of patients undergoing pancreaticoduodenectomy (PD), hypothesizing that patients developing inflammatory POAE defined as leucocytosis, fever or high (above median) area under the curve (AUC) C-reactive protein (CRP) the first post-operative week would display perturbed preoperative immune function. Sixty-two adult patients were screened, 30 included and 11 excluded post-inclusion due to other surgical procedures than PD and post-operative complications directly attributed to surgery, leaving 19 patients for analysis of preoperative immune function. Patients developing leucocytosis (n = 5, 26%) had lower Toll-like receptor (TLR)-3–stimulated IL-12p40 and higher Candida Albicans (TLR1/2/4/6, Dectin-1)-stimulated TNF-α, compared to patients without leucocytosis (all P < .05). Patients developing fever (n = 7, 37%) had lower TLR7/8-stimulated IFN-γ and patients with high AUC CRP (n = 9, 47%) had lower TLR3-stimulated IFN-γ and IL-6 and lower TLR7/8-stimulated IL-10 (all P < .05), compared to patients without fever or low CRP, respectively. In conclusion, patients with inflammatory POAE displayed lower preoperative stimulated IL-12p40, IFN-γ, IL-6 and IL-10 and higher TNF-α response, compared to patients without inflammatory POAE. This finding suggests that TruCulture is a feasible immunologic screening tool in surgical patients, with a potential for preoperative identification of patients at increased risk for inflammatory POAE, allowing for risk-based intervention trials. 相似文献
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