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排序方式: 共有722条查询结果,搜索用时 31 毫秒
21.
X. Lu A.J. Forte F. Fan Z. Zhang L. Teng B. Yang M. Alperovich D.M. Steinbacher N. Alonso J.A. Persing 《The British journal of oral & maxillofacial surgery》2021,59(5):579-585
The altered orbital morphology of patients with Crouzon syndrome could have an impact on the planning of treatment in diverse populations, in spite of the confounding influences of different cranial suture synostosis. This study attempted to explore the differences in orbital characteristics between Asian, Caucasian patients with Crouzon syndrome, associated pansynostosis. Eighty-six preoperative computed tomograms (CT) were included (Asian Crouzon syndrome: n=10; Asian controls: n=24; Caucasian Crouzon syndrome: n=19; Caucasian controls: n=33) and measured using Mimics software (Materialise). Unique cephalometric measurements related to orbital morphology and position were designed. Crouzon syndrome and race both have interactive effects on protrusion of the globe (p=0.009) and medial horizontal angle (p=0.012) in the assessment of orbital morphology. They also interact in the width of the ethmoid sinus (p=0.009) and influence bilateral orbital relations. The anteroposterior orbital roof in Caucasian patients with Crouzon syndrome was shortened by 4.09 mm (p=0.002) compared with Caucasian controls. However, in Asian patients this dimension developed normally. The anteroposterior orbital floor was significantly reduced to a similar extent in both Asian and Caucasian Crouzon patients (both p<0.001). The visual axes in Caucasian patients with Crouzon showed more inferior rotation, by 4.38° (p=0.031) than they did in Caucasian controls, but did not achieve a statistically significant difference in other comparisons. The effect of Crouzon syndrome on orbital malformation and placement is influenced by race, especially structures related to the ethmoid sinus. Asian patients need greater infraorbital advancement for better correction of orbital proptosis and aesthetic benefits, but may require less fronto-orbital advancement than Caucasian patients. 相似文献
22.
Gazitt Y; Reading CC; Hoffman R; Wickrema A; Vesole DH; Jagannath S; Condino J; Lee B; Barlogie B; Tricot G 《Blood》1995,86(1):381-389
High-dose therapy with autologous marrow or peripheral blood stem cell (PBSC) rescue has been extensively applied in the treatment of multiple myeloma (MM) patients during the past 10 years resulting in improved event-free and overall survival when compared with standard chemotherapy. However, relapses are common and cure is unlikely in the majority of patients. Because both bone marrow and PBSCs are contaminated with myeloma cells it is conceivable that relapse after autotransplantation originates at least in part from autografted tumor cells. In this study, mobilized PBSCs were examined for the presence of myeloma cells based on immunophenotyping and sensitive polymerase chain reaction (PCR)-based techniques. In addition, CD34+ Lin- Thy+ stem cells were purified from mobilized PBSC harvests of 10 MM patients by sequentially using counterflow elutriation centrifugation, treatment with phenylalanine methylester, and flow sorting, using 5-parameter gating (propidium iodide, forward scatter, side scatter, CD34+ v Lin- and CD34+ v Thy+). Virtually all mobilized unsorted PBSC preparations contained myeloma cells in sufficient quantities (range, < 0.01 to > 10%) potentially causing a disease relapse. Stem cell purification led to an overall enrichment by about 50-fold in all 10 patients; approximately 90% of the final cell population expressed CD34+ Lin- Thy+ with no evidence of myeloma cell contamination based on flow cytometric analysis of CD38bright cells (< 0.1%). Quantitative PCR amplification of patient-specific complementarity determining region III (CDRIII) DNA sequences showed depletion of clonal B cells by 2.7 to 7.3 logs, with the highest log reduction noted in the samples initially containing the most tumor cells. Our results show that purification of CD34+ Lin- Thy+ cells depletes myeloma cells to undetectable levels from up to 10% present in unsorted PBSCs, thus offering a tool to investigate whether MM relapse after autotransplantation can be reduced markedly. 相似文献
23.
Increased arthritis severity in mice coinfected with Borrelia burgdorferi and Babesia microti 总被引:1,自引:0,他引:1
Moro MH Zegarra-Moro OL Bjornsson J Hofmeister EK Bruinsma E Germer JJ Persing DH 《The Journal of infectious diseases》2002,186(3):428-431
Increased severity of disease and persistence of symptoms have been recently reported in some patients with simultaneous infection of Borrelia burgdorferi and Babesia microti in the northeastern and northern midwest United States. This study used a murine model to examine whether defined disease conditions such as arthritis and carditis differed in severity in mice infected solely with B. burgdorferi and in mice coinfected with B. microti and B. burgdorferi. C3H.HeJ and BALB/c mice cohorts were coinfected or singly infected and then monitored experimentally for 15 and 30 days after inoculation. Carditis and arthritis was determined by blinded histopathologic evaluation of myocardium and tibiotarsal joints. Cytokine measurements were made on lymph node and spleen supernatants for interferon-gamma, interleukin (IL)-4, IL-10, and IL-13. No differences were observed for C3H.HeJ mice cohorts; however, coinfected BALB/c mice had a significant increase in arthritis severity at day 30. This clinical observation was correlated with a significant reduction in expression of the cytokines IL-10 and IL-13. 相似文献
24.
[Purpose] The purpose of this study was to investigate the use of smartphones by
university students in selected areas, their musculoskeletal symptoms, and the associated
hazard ratio. [Subjects and Methods] This involved the completion of a self-administered
questionnaire by dental hygiene students in Seoul, Gyeonggido, and Gyeongsangbukdo. The
292 completed copies of the questionnaire were then analyzed. [Results] The most painful
body regions after the use of smartphones were found to be the shoulders and neck. In the
musculoskeletal system, back pain was found to have a positive correlation with the size
of the smartphone’s liquid crystal display (LCD) screen, and pain in legs and feet were
found to have a negative correlation with the length of time that the smartphone was used.
As a result, it was revealed that the use of a smartphone was correlated with
musculoskeletal symptoms. [Conclusion] Therefore, in today’s environment, where the use of
smartphones is on the rise, it is necessary to improve the ways that they are used and to
develop a preventive program to alleviate the symptoms of musculoskeletal damage.Key words: Smartphone, Musculoskeletal symptoms, Prevent 相似文献
25.
The accuracy of International Classification of Diseases coding for dental problems not associated with trauma in a hospital emergency department
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26.
Patel A Chang CC Terner JS Tuggle CT Persing JA 《The Journal of craniofacial surgery》2012,23(2):370-373
Orbital rim deficits are a feature of metopic, unilateral coronal, and bilateral coronal craniosynostosis. Several procedures have been developed to address this issue, but relapse to the preoperative hypoplastic deformity and stunted growth of the fronto-orbital region are common. The authors describe a technique modification of the conventional lateral canthal advancement referred to as the orbital rim "tilt" procedure, which aims to preserve inferior bony support for the orbital rim and create projection with optimal proclination of the fronto-orbital complex. 相似文献
27.
DH Mallon M Kostalas FJ MacPherson A Parmar A Drysdale E Chisholm 《Annals of the Royal College of Surgeons of England》2013,95(4):258-262
Introduction
Fine needle aspiration (FNA) is a safe and quick method of diagnosing superficial lumps, which aids preoperative planning. However, FNA of the parotid gland has not gained the widespread acceptance noted in other head and neck lumps. The aim of this study was to determine the ability of FNA of the parotid gland to differentiate benign and malignant disease, and to determine the impact on surgical outcome.Methods
A retrospective analysis of 201 consecutive parotid operations with preoperative FNA in a large district hospital in the UK was performed. The diagnostic characteristics were calculated for benign and malignant disease, and the impact on surgical procedure was determined.Results
In identifying benign disease, FNA has a sensitivity of 85% and a specificity of 76%. In detecting malignant disease, FNA has a sensitivity and specificity of 52% and 92% respectively. A false positive on FNA was associated with a higher incidence of neck dissection.Conclusions
FNA is a useful diagnostic test. However, owing to low sensitivity, it is necessary to interpret it in the context of all other clinical information. 相似文献28.
Femke?DH?Koedijk Birgit?HB?van BenthemEmail author Eliane?MDC?Vrolings Wim?Zuilhof Marianne?AB?van der Sande 《Emerging themes in epidemiology》2014,11(1):12
Background
Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.Methods
Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.Results
In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.Conclusions
MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.29.
Gazitt Y; Tian E; Barlogie B; Reading CL; Vesole DH; Jagannath S; Schnell J; Hoffman R; Tricot G 《Blood》1996,87(2):805-811
Peripheral blood stem cells (PBSCs) mobilized with high-dose chemotherapy and hematopoietic growth factors are now widely used to support myeloablative therapy of multiple myeloma and effect complete remissions in up to 50% of patients with apparent extension of event- free and overall survival. Because tumor cells are present not only in bone marrow, but also in virtually all PBSC harvests, it is conceivable that autografted myeloma cells contribute to relapse after autotransplants. In this study, the kinetics of mobilization of normal hematopoietic stem cells were compared with those of myeloma cells present in PBSC harvests of 12 patients after high-dose cyclophosphamide and granulocyte-macrophage colony-stimulating factor administration. CD34+ and CD34+Lin-Thy+ stem cell contents were measured by multiparameter flow cytometry, and myeloma cells were quantitated by immunostaining for the relevant Ig light chain and by a quantitative polymerase chain reaction for the myeloma-specific CDRIII sequence. Results indicated marked heterogeneity in the percentages of mobilized stem cells among different patients (0.1% to 22.2% for CD34+ cells and 0.1% to 7.5% for CD34+Lin-Thy+ cells, respectively). The highest proportions of hematopoietic progenitor cells were observed early during apheresis, with 9 of 12 patients mobilizing adequate amounts of CD34+ cells for 2 autotransplants (> 4 x 10(6)/kg) within the first 2 days, whereas peak levels (percent and absolute numbers) of myeloma cells were present on days 5 and 6 (0.5% to 22.0%). During the last days of collection, mobilized tumor cells exhibited more frequently high labeling index values (1% to 10%; median, 4.4%) and an immature phenotype (CD19+). The differential mobilization observed between normal hematopoietic stem cells and myeloma cells can be exploited to reduce tumor cell contamination in PBSC harvests. 相似文献
30.
Adhesion of platelets to surface-bound fibrinogen under flow 总被引:2,自引:2,他引:2
After platelet activation, fibrinogen mediates platelet-platelet interactions leading to platelet aggregation. In addition, fibrinogen can also function as a cell adhesion molecule, providing a substratum for adhesion of platelets and endothelial cells. In this report, we studied the adhesion of platelets to surface-immobilized fibrinogen under flow in different shear rates. Heparinized whole blood containing mepacrine-labeled platelets was perfused for two minutes at various wall shear rates from 250 to 2,000 s-1 in a parallel plate flow chamber. The number of adherent fluorescent platelets was quantitated every 15 seconds with an epifluorescent videomicroscope and digital image processing system. When compared with platelet adhesion and aggregation seen on glass surfaces coated with type I bovine collagen, a significant increase in platelet adhesion was observed on immobilized fibrinogen up to wall shear rates of 800 s-1. The adherent platelets formed a single layer on fibrinogen-coated surfaces. Under identical conditions, no significant adhesion was observed on fibronectin- or vitronectin-coated surfaces. Although platelet adhesion to collagen was substantially inhibited by the platelet inhibitors prostaglandin E1 and theophylline, these inhibitors had no effect on platelet adhesion to fibrinogen. Platelets adhered to recombinant homodimeric wild-type (gamma 400-411) fibrinogen, but not to the recombinant homodimeric gamma' variant of fibrinogen. Platelet adhesion to recombinant fibrinogen with RGD to RGE mutations at positions alpha 95-97 and alpha 572-574 was similar to that with plasma-derived fibrinogen. These results show that platelets adhere to fibrinogen-coated surfaces under moderate wall shear rates, that the interaction is mediated by the fibrinogen 400-411 sequence at the carboxy-terminus of the gamma chain, and that the interaction is independent of platelet activation and the RGD sequences in the alpha chain. 相似文献