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排序方式: 共有2631条查询结果,搜索用时 562 毫秒
91.
92.
Humam Saltaji Michael P. Major Mostafa Altalibi Mohamed Youssef Carlos Flores-Mir 《The Angle orthodontist》2012,82(6):1115
Objective:To systematically review the long-term skeletal stability after maxillary advancement with distraction osteogenesis (DO) in cleft lip and palate (CLP) patients.Materials and Methods:Electronic databases, grey literature, and reference list searches were conducted. The inclusion criteria were stability of maxillary advancement with distraction osteogenesis assessed at the posttreatment follow-up ≥ 1 year in CLP patients. Full articles were retrieved from abstracts or titles that appear to meet the inclusion criteria or lacked sufficient detail for immediate exclusion. Once full articles were collected, they were again reviewed considering more detailed inclusion criteria for a final selection decision. A methodologic quality assessment tool was utilized.Results:Thirty abstracts/titles met the initial search criteria, and 13 articles were finally selected. Overall, methodologic quality scores were high in only one randomized clinical trial. After maxillary advancement with DO in CLP patients, the long-term horizontal relapse in A-point was less than 15% in eight studies and between 20% and 25% in four studies. The study that was judged as a high-quality study reported 8.2% horizontal relapse in A-point. The relapse rate was higher in DO with external distracter device than DO with internal distracter device.Conclusions:Current evidence suggests maxillary advancement with DO has good stability in CLP patients with moderate and severe maxillary hypoplasia. 相似文献
93.
Altered Immunogenicity of Donor Lungs via Removal of Passenger Leukocytes Using Ex Vivo Lung Perfusion 下载免费PDF全文
J. P. Stone W. R. Critchley T. Major G. Rajan I. Risnes H. Scott Q. Liao B. Wohlfart T. Sjöberg N. Yonan S. Steen J. E. Fildes 《American journal of transplantation》2016,16(1):33-43
Passenger leukocyte transfer from the donor lung to the recipient is intrinsically involved in acute rejection. Direct presentation of alloantigen expressed on donor leukocytes is recognized by recipient T cells, promoting acute cellular rejection. We utilized ex vivo lung perfusion (EVLP) to study passenger leukocyte migration from donor lungs into the recipient and to evaluate the effects of donor leukocyte depletion prior to transplantation. For this purpose, female pigs received male left lungs either following 3 h of EVLP or retrieved using standard protocols. Recipients were monitored for 24 h and sequential samples were collected. EVLP‐reduced donor leukocyte transfer into the recipient and migration to recipient lymph nodes was markedly reduced. Recipient T cell infiltration of the donor lung was significantly diminished via EVLP. Donor leukocyte removal during EVLP reduces direct allorecognition and T cell priming, diminishing recipient T cell infiltration, the hallmark of acute rejection. 相似文献
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95.
Chronic masticatory myalgia (CMM) can be defined as constant pain in the masticatory muscles for more than 6 months and is influenced by the central nervous system. The antiepileptic agent gabapentin acts centrally and is used for managing different types of chronic pain conditions. The objective of this study was to evaluate the analgesic action of gabapentin on CMM. In this 12-week randomized controlled clinical trial 50 patients were randomly allocated into two study groups: 25 received gabapentin and 25 received placebo. The outcome measures utilized were pain reported on a VAS (VAS-pain), Palpation Index (PI) and impact of CMM on daily functioning reported on a VAS (VAS-function). Thirty-six patients completed the study. Gabapentin showed to be clinically and statistically superior to placebo in reducing pain reported by patients (gabapentin=51.04%; placebo=24.30%; P=0.037), masticatory muscle hyperalgesia (gabapentin=67.03%; placebo=14.37%; P=0.001) and impact of CMM on daily functioning (gabapentin=57.70%; placebo=16.92%; P=0.022). It can be concluded from this study that gabapentin is effective for the management of CMM. 相似文献
96.
BACKGROUND: Previous evaluations showed that literature-search and selection methods reported in dental systematic reviews (SR) have improved since 2000. It is not known, however, whether these differences are consistent between the SR of the different dental specialities. METHODS: SR in dentistry published in the English language between 1 January 2000 and 14 June 2006 were located and then categorised by American Dental Association (ADA) recognised specialities. Search and selection methods were evaluated following an adaptation of the Cochrane Handbook for Systematic Reviews. Search and selection methods between dental specialities were compared using Pearson's chi-squared analysis and ranked. RESULTS: There were significant differences between specialities in the following criteria: documentation of search dates (P 0.003); inclusion-exclusion documentation (P 0.017); article selection by two or more reviewers (P 0.001); and inclusion of all languages (P 0.014). Periodontics SR met the most criteria followed by oral and maxillofacial surgery (OMS) and then dental public heath (DPH). Prosthodontics along with the area of oral and maxillofacial radiology (OMR) met the fewest. All dental SR had low compliance with four criteria, only 65.7% searched more than Medline, 50.4% had a search strategy documented with Boolean operators, 51.5% had article selection carried out by two or more reviewers and only 25.7% included all languages. CONCLUSIONS: Some dental specialities are better at reporting search and selection methods than others but all dental SR need some improvement in their reporting. 相似文献
97.
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
98.
99.
L Feigenbaum K Khalili E Major G Khoury 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(11):3695-3698
Human papovavirus JCV is associated with the human demyelinating disorder progressive multifocal leukoencephalopathy. In tissue culture, the virus is largely restricted to growth in primary human fetal glial cell. In this study, we demonstrate two levels of regulation of the viral host range. Expression of the early JCV mRNA, which encodes the essential viral protein, large tumor antigen (T antigen), depends on recognition of the early enhancer/promoter elements by tissue-specific factors found in both human and rodent glial cells. In the presence of JCV T antigen, viral DNA replication requires a species-specific factor, presumably a component of DNA polymerase, which is found in a wide range of primate cells. We further demonstrate that simian virus 40 T antigen has sufficient homology to efficiently substitute for the analogous JCV protein in initiating viral DNA replication. 相似文献
100.
Subclasses of cyclic GMP-specific phosphodiesterase and their role in regulating the effects of atrial natriuretic factor 总被引:3,自引:0,他引:3
R E Weishaar D C Kobylarz-Singer J Keiser S J Haleen T C Major S Rapundalo J T Peterson R Panek 《Hypertension》1990,15(5):528-540
Two subclasses of cyclic guanosine monophosphate (GMP)-specific phosphodiesterases were identified in vascular tissue from several beds. The activity of one subclass (phosphodiesterase IB) was stimulated severalfold by calmodulin and selectively inhibited by the phosphodiesterase inhibitor TCV-3B. The activity of the other subclass (phosphodiesterase IC) was not stimulated by calmodulin and was selectively inhibited by the phosphodiesterase inhibitor M&B 22,948. To assess the involvement of both subclasses in regulating cyclic GMP-dependent responses, the ability of TCV-3B and M&B 22,948 to potentiate the in vitro and in vivo responses to the endogenous guanylate cyclase stimulator atrial natriuretic factor (ANF) was evaluated. Both TCV-3B and M&B 22,948 relaxed isolated rabbit aortic and pulmonary artery rings and also potentiated the relaxant effect of ANF. In addition, both inhibitors produced small increases in urine flow and sodium excretion in anesthetized rats and potentiated the diuretic and natriuretic responses to exogenous ANF. M&B 22,948 (30 micrograms/kg/min) produced a threefold increase in the natriuretic response to simultaneously administered ANF, and TCV-3B (10 micrograms/kg/min) produced a twofold increase in the response to ANF. The results of the present experiments suggest that both the calmodulin-sensitive and calmodulin-insensitive subclasses of cyclic GMP-specific phosphodiesterase play a role in regulating the in vitro and in vivo response to ANF. 相似文献