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61.
Journal of Anesthesia - 相似文献
62.
《The Knee》2022
BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes. 相似文献
63.
Monoclonal antibodies against human granulocytes and myeloid differentiation antigens 总被引:4,自引:0,他引:4
Patrice Mannoni Anna Janowska-Wieczorek A. Robert Turner Locksley McGann Jean-Michael Turc 《Human immunology》1982,5(4):309-323
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis. 相似文献
64.
Alberto Utrero-Rico Javier Ruiz-Hornillos Cecilia González-Cuadrado Claudia Geraldine Rita Berta Almoguera Pablo Minguez Antonio Herrero-González Mario Fernández-Ruiz Octavio Carretero Juan Carlos Taracido-Fernández Rosario López-Rodriguez Marta Corton José María Aguado Luisa María Villar Carmen Ayuso-García Estela Paz-Artal Rocio Laguna-Goya 《The Journal of allergy and clinical immunology》2021,147(5):1652-1661.e1
65.
B J Appelmelk A M Verweij-Van Vught D M MacLaren L G Thijs 《Journal of immunological methods》1985,82(2):199-207
Bovine serum albumin was complexed with the core antigens of either Escherichia coli J5 LPS, Salmonella minnesota R595 LPS or E. coli lipid A. These core-BSA complexes were used for solid-phase coating in ELISAs for anti-core antibodies. Antibodies, binding to various parts of the core region were easily quantified in a single experimental set-up, which was hitherto not possible. The ELISA has only 3 incubation steps and is not costly as only moderate amounts of the core antigens (i.e., 1 microgram per test) were needed for coating. The sensitivity proved to be excellent and the complexes were biologically fully active (compared to native, smooth LPS), which make them suitable for the screening (after fusion) of monoclonal anti-core antibodies. Another possible application is the large-scale screening of blood-bank sera in order to find samples with a high anti-core antibody content. 相似文献
66.
采用半固体一步单层琼脂培养法和单克隆荧光抗体技术分别观察重症肝炎外周血TL-CFU和mIL-2R,发现重症肝炎患者TL-CFU(104.4±32.6)及mIL-2R(35.6±8.6)较正常人明显降低。在培养体系中加胎肝细胞质液后,无论在重症肝炎组还是在正常组均不能明显地提高TL-CFU,说明胎肝细胞质液不含具生物佐的促TL-CFU因子。但对mIL-2R表达的影响,在重症肝炎组病人,只有在PHA存在条件下才能促进mIL-2R的表达,说明胎肝细胞质波含有某种(些)物质能协同PHA促进重症肝炎患者外周血淋巴细胞mIL-2R表达。 相似文献
67.
Background
As assessment with inertial-measurement-units (IMUs) increases in research and in clinics, it is important to be aware of the repeatability of these sensors. The objectives of this experiment were to evaluate the measurement repeatability of IMU joint angles using a repeatable robot controller and an anthropomorphic leg phantom and to determine effects of joint speed and sensor positioning on the angles collected by these sensors. Comparisons to an electro-goniometer and three-dimensional (3D) motion capture cameras were also completed.Methods
Two dual-IMU setups (posterior and lateral) were tested concurrently with an electro-goniometer and 3D motion capture cameras using a repeatable robot controller and a leg phantom. All modalities were attached to the phantom, which was flexed 10 times using a pre-programmed motion pathway during each test. Mean angles were compared across tests. Effects of joint speed, sensor re-positioning, and anatomical placement of the sensors on repeatability were assessed.Results
Re-positioning caused greater deviation to the maximum and minimum angles than differences in speed. Overall, the means?±?standard deviations, and 95% confidence intervals of the maximum angles across all tests for the 3D camera markers, electro-goniometer, posterior IMUs, and lateral IMUs were 119.4?±?0.3° (119.4, 119.5), 112.4?±?0.5° (112.3, 112.5), 116.2?±?2.4° (115.7, 116.7), and 118.3?±?1.1° (118.1, 118.6).Conclusions
Both posterior and lateral IMU setups demonstrated acceptable repeatability in measurement of range of motion that was advantageous to manual goniometer methods. Posterior and lateral IMU setups demonstrated overlapping standard deviations about their means. 相似文献68.
D. I. Perrett M. W. Oram M. H. Harries R. Bevan J. K. Hietanen P. J. Benson S. Thomas 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,86(1):159-173
Summary An investigation was made into the sensitivity of cells in the macaque superior temporal sulcus (STS) to the sight of different perspective views of the head. This allowed assessment of (a) whether coding was viewer-centred (view specific) or object-centred (view invariant) and (b) whether viewer-centred cells were preferentially tuned to characteristic views of the head. The majority of cells (110) were found to be viewer-centred and exhibited unimodal tuning to one view. 5 cells displayed object-centred coding responding equally to all views of the head. A further 5 cells showed mixed properties, responding to all views of the head but also discriminating between views. 6 out of 56 viewer and object-centred cells exhibited selectivity for face identity or species. Tuning to view varied in sharpness. For most (54/73) cells the angle of perspective rotation reducing response to half maximal was 45–70° but for 19/73 it was >90°. More cells were optimally tuned to characteristic views of the head (the full face or profile) than to other views. Some cells were, however, found tuned to intermediate views throughout the full 360 degree range. This coding of many distinct head views may have a role in the analysis of social signals based on the interpretation of the direction of other individuals' attention. 相似文献
69.
Dr. J. D. Pettigrew Dr. T. Nikara Prof. P. O. Bishop 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1968,6(4):373-390
Summary A quantitative study has been made of the responses to moving slit stimuli by single units in the cat striate cortex whose receptive fields lay within 5° of the visual axis. Special attention was given to finding the optimal stimulus parameters including slit width, length, orientation and speed. The analysis was largely based on averaged response vs. time histograms. Using the classification of simple and complex responses types, the units were further subdivided on the basis of the number of modes in the response and on the presence or absence of directional selectivity. Simple unimodal units with directional selectivity (SUDS) had the most specific stimulus requirements and nearly always had zero background activity. Complex units usually had a high level of background activity. SUDS units also showed a preference for horizontally- and vertically ****-orientated stimuli. Whenever the response survived reversal of contrast the directional selectivity remained independent of the change. Optimal stimulus speeds varied widely from unit to unit with a mean at 4°/sec: simple bimodal units and complex units tended to have higher optimal stimulus speeds and responded over a wider range of speeds than did simple unimodal units. While SUDS units with very small receptive fields tended to prefer slowly moving stimuli, in general there was no correlation between receptive field size and optimal stimulus speed.Selby Fellow of the Australian Academy of Sciences. 相似文献
70.
Tissue cages for study of experimental streptococcal infection in rabbits. I. Production of erythrogenic toxins in vivo 总被引:2,自引:0,他引:2
Tissue cages implanted subcutaneously were used to infect rabbits with erythrogenic toxin (ET) producing streptococci. The in-vivo production of ET was followed during the infection by immunoprecipitation analyses of the tissue cage fluid (TCF). ET types A and C were mainly detected during the first week of infection, but, as late as 4 weeks after the inoculation, ET was occasionally found in TCF. The nonspecific mitogenic activity of ET on human lymphocytes was also used as a biological marker to recognize ET in TCF. Mitogenic activity was detected in 90% of samples during the first week. In order to characterize the mitogenic material released by growing streptococci, TCF was electrofocused in polyacrylamide gel. The eluates of sliced gels were checked for mitogenic activity and compared with a purified ET preparation containing ET types A and C. It could be verified that ET type A was produced under in-vivo conditions by strains NY-5 and SF130, while ET type C was produced by strain T18. Differences between production of toxins in vitro and in vivo might be of significance for the understanding of the pathogenetic mechanisms in streptococcal infection. 相似文献