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Frank G. Shellock Jerrold H. Mink Andrew L. Deutsch James Fox Todd Molnar Ronald Kvitne Richard Ferkel 《Journal of magnetic resonance imaging : JMRI》1994,4(4):590-594
The effect of a newly developed patellar realignment brace was evaluated in 21 patellofemoral joints (19 patients) with patellar subluxation (13 joints with lateral subluxation and eight with medial subluxation) by using active-movement, loaded kinematic magnetic resonance (MR) imaging. Sixteen patellofemoral joints (76%) demonstrated a qualitative correction of or improvement in patellar subluxation (ie, centralization of the patella or a decrease in the displacement of the patella) after application of the brace. Four of the five “failures” occurred in patellofemoral joints that had patella alta and/or dysplastic bone anatomy. These results indicate that the patellar realignment brace was able to counteract patellar subluxation in the majority of patellofemoral joints studied, as shown by active-movement, loaded kinematic MR imaging. This brace appears to be useful for conservative treatment of patients with patellofemoral joint pain secondary to patellar malalignment and maltracking. 相似文献
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目的:了解广西地区儿童铅中毒状况,研究铅对婴儿神经发育的影响。方法:选择1020名婴儿,以脐血铅作为铅暴露示标,3月龄时在贝利(Bayley)婴儿发育表上以精神发育指数(MDI)和心理运动发育指数(PDI)为效应示标。结果:血铅≥0.48μmol/L的婴儿其MDI和PDI明显落后于相对低铅组,随着分界线的下移,两组间MDI和PDI差别渐趋缩小,当分界线为0.24μmol/L时,高、低铅组MDI和PDI已不存在统计学差异。结论:当血铅≥0.48μmol/L时,婴儿神经行为发育即可受到不利影响。 相似文献
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Immune modulation by cadmium and lead in the acute reporter antigen-popliteal lymph node assay. 总被引:2,自引:0,他引:2
Immune modulation by heavy metals may cause serious adverse health effects in humans, although the mechanisms involved are not well understood. Both cadmium and lead are important environmental and occupational toxins. Therefore, in the current study, the costimulatory/adjuvant effects and the T-cell-activating potential of these metals (i.e., CdCl2 and PbCl2), are examined. These immune-modulating properties are critical in the development of conditions such as allergy, hypersensitivity, and autoimmunity. Using the direct popliteal lymph node assay (PLNA) and reporter antigen-popliteal lymph node assay (RA-PLNA) both metals were examined individually for immunotoxicity. Mercury (i.e., HgCl2) was included for comparative purposes as its effects in the RA-PLNA are well documented. Seven days following a single footpad injection containing metal and/or RA (trinitrophenyl-ovalbumin [TNP-OVA] or TNP-Ficoll), BALB/c mice were sacrificed and the popliteal lymph nodes (PLNs) removed. PLN cellularity, TNP-specific antibody-secreting cells (ASCs), and lymphocyte subsets were assessed. All three metals strongly stimulated T- and B-cell proliferation and ASC production following coinjection with the RA TNP-OVA. In each case, ASC production was skewed towards the IgG1 isotype. In addition, all three metals induced IgG production to TNP-Ficoll (although relatively weakly in the case of Cd). These results show that each of these metals can provide adjuvant signals to promote lymphocyte proliferation and enhance adaptive immune responses to unrelated antigens. Skewing of immune responses towards T helper type 2 responses suggests that each of these metals can enhance allergic and hypersensitivity reactions to environmental antigens. Furthermore, the induction of IgG responses to TNP-Ficoll, a T-cell-independent antigen, indicates that each of these metals can activate neoantigen-specific T cells. T-cell activation by metals can lead to metal hypersensitivity and has been implicated in the development of autoimmunity. This is the first report of immune modulation by CdCl2 and PbCl2 in the RA-PLNA. 相似文献
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目的探讨陈旧性髌骨骨折的治疗方法。方法对11例陈旧性髌骨骨折进行回顾性总结,采用保留髌骨,切开复位,松解粘连,改良张力带钢丝或/和聚髌器坚强的内固定,术后配合CPM机康复锻炼。结果11例全部随访,随访0.5~4.5年,根据胥少汀等制定的评定标准,优4例,良5例,优良率81.8%。结论不做髌骨切除,松解粘连、良好的对位,坚强的内固定,早期配合应用CPM机进行功能锻炼,可取得满意的疗效。 相似文献
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A VDD pacing system with bipolar single-pass leads, were implanted in 36 consecutive patients (average age 72 ± 2years) with high degree atrioventricular block and normal sinus node function. At implant the atrial signal amplitude was 2.6 ± 0.2mV measured by a pacing system analyser (PSA), 1.8 ± 0.1mV measured peak-to-peak from the telemetered calibrated electrogram, and 1.3 ± 0.1mV measured from the sensing threshold. At one month follow-up the peak-to-peak amplitudes (mV) of the telemetered atrial electrograms were not significantly different measured continuously during resting supine with quiet breathing (1.4 ± 0.1), sitting (1.6 ± 0.2). standing (1.5 ± 0.1), arm swinging (1.4 ± 0.2), hyperventilation (1.3 ± 0.1), Vaisalva manoeuvre (1.4 ± 0.1), and treadmill exercise (1.9 ± 0.6). The telemetered atrial electrogram amplitude and the atrial sensing threshold varied between 1.2 ± 0.09mV and 1.8 ± 0.1mV, and between 0.95 ± 0.07mV and 1.3 ± 0.01mV, respectively at 0.5, 1, 3, 6 and 12 months follow-up, but the changes were statistically nonsignificant. The Event Summary showed sensing of 98% to 99% of the atrial events at the different follow-up periods. 相似文献
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Jim-Shoung Lai T.-N. Wu Saou-Hsing Liou Chen-Yang Shen Chiam-Fang Guu Kquei-Nu Ko Chi. Hsueh-Yun P.-Y. Chang 《International archives of occupational and environmental health》1997,69(4):295-300
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship
between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were
measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics
and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear
regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol
consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although
PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based
on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient
lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood
lead levels in lead battery factories.
Received: 28 May 1996/Accepted: 30 August 1996 相似文献
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