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排序方式: 共有2635条查询结果,搜索用时 16 毫秒
81.
82.
Vignon E Piperno M Le Graverand MP Mazzuca SA Brandt KD Mathieu P Favret H Vignon M Merle-Vincent F Conrozier T 《Arthritis and rheumatism》2003,48(2):378-384
OBJECTIVE: To evaluate progression of joint space narrowing in radiographs of osteoarthritic (OA) knees imaged in both the standing anteroposterior (AP) and the Lyon schuss positions, using alternative methods to measure joint space width (JSW). METHODS: Standing AP (extended view) and Lyon schuss (posteroanterior [PA] view, with 20-30 degrees of flexion) radiographic images of 58 OA knees were obtained twice (at baseline and 2 years later). With both methods, fluoroscopy was used to align the anterior and posterior margins of the medial or lateral tibial plateau with the central x-ray beam. Minimum JSW, mean JSW, and joint space area (JSA) of the medial or lateral femorotibial joint space were measured using a new digital image analysis system. The effects of knee flexion versus extension and parallel versus nonparallel tibial plateau alignment were evaluated with respect to the reproducibility of JSW in repeated examinations (intraclass correlation coefficient [ICC]), the mean of within-knee standard deviations of repeated measurements (SD(m)), and the sensitivity to changes in JSW in serial radiographs (standardized response mean [SRM]). RESULTS: The performance of the new software, as assessed by the reproducibility of repeated measurements of minimum JSW on the same image, was excellent in both the standing AP (ICC = 0.98) and Lyon schuss radiographs (2 SD(m) = 0.5 mm, ICC = 0.98). The reproducibility in different radiographs of the same knee was not evaluated. However, over 2 years, the mean (+/- SD) decrease in the minimum JSW of OA knees was 0.17 +/- 0.75 mm in standing AP radiographs (P not significant) and 0.24 +/- 0.50 mm in Lyon schuss views (P = 0.007), with SRMs of 0.23 and 0.48, respectively. The quality of alignment of the tibial plateau was satisfactory (<1 mm between anterior and posterior margins of the medial tibial plateau) in 66% of the pairs of Lyon schuss radiographs and in 57% of the pairs of standing AP radiographs. In the Lyon schuss radiographs, SRM was highly dependent on tibial plateau alignment. Minimum JSW was more sensitive to change than was mean JSW or JSA, in paired Lyon schuss radiographs that exhibited satisfactory alignment. CONCLUSION: Compared with the standing AP radiograph, PA imaging of the knee in 20-30 degrees flexion (the schuss position) increases the reproducibility of radiographic JSW measurements in OA knees and the sensitivity to change in JSW in serial radiographs. Sensitivity to change in minimum JSW is notably increased by aligning the medial tibial plateau with the central x-ray beam in the Lyon schuss radiograph. 相似文献
83.
Toyin Janet Aderemi Muriel Mac-Seing Seblewangel Ayalew Woreta Komi Agbemavi Mati 《AIDS care》2014,26(12):1461-1466
The study investigated HIV testing prevalence and factors associated with the utilization of voluntary HIV counselling and testing (VCT) services among individuals with disabilities in Addis Ababa. The analysis was based on a survey of 209 men and 203 women with disabilities, aged 15–49, who had ever heard about HIV and AIDS in four sub-cities in Addis Ababa. HIV testing prevalence was 53.2%, with no significant difference between males and females. Comprehensive HIV knowledge, living with spouse, and religious affiliations positively predicted utilization of VCT services among participants. Living with both parents and having physical or mental/intellectual disabilities were negative predictors of VCT services utilization. More research on the predictors of utilization of VCT services by gender and urban/rural divides are needed among people with disabilities. 相似文献
84.
85.
Magali de Heusch Valérie Steenwinckel Perrine M. Cochez Jamila Louahed Guy Warnier Muriel M. Lemaire Jean-Christophe Renauld Laure Dumoutier 《European journal of immunology》2020,50(7):1034-1043
IL-9 is involved in various T cell-dependent inflammatory models including colitis, encepahlitis, and asthma. However, the regulation and specificity of IL-9 responsiveness by T cells during immune responses remains poorly understood. Here, we addressed this question using two different models: experimental colitis induced by transfer of naive CD4+CD45RBhigh T cells into immunodeficient mice, and OVA-specific T cell activation. In the colitis model, constitutive IL-9 expression exacerbated inflammation upon transfer of CD4+CD45RBhigh T cells from WT but not from Il9r−/− mice, indicating that IL-9 acts directly on T cells. Suprisingly, such naïve CD4+CD45RBhigh T cells failed to express the Il9r or respond to IL-9 in vitro, in contrast with CD4+CD45RBlow T cells. By using OVA-specific T cells, we observed that T cells acquired the capacity to respond to IL-9 along with CD44 upregulation, after long-lasting (5 to 12 days) in vivo antigenic stimulation. Il9r expression was associated with Th2 and Th17 phenotypes. Interestingly, in contrast to the IL-2 response, antigen restimulation downregulated IL-9 responsiveness. Taken together, our results demonstrate that IL-9 does not act on naïve T cells but that IL-9 responsiveness is acquired by CD4+ T cells after in vivo activation and acquisition of memory markers such as CD44. 相似文献
86.
Amandine Drut Isabelle Bublot Edward B. Breitschwerdt Luc Chabanne Muriel Vayssier-Taussat Jean-Luc Cadoré 《Medical microbiology and immunology》2014,203(2):85-91
We report the first documented case of Bartonella henselae infection in a dog from France and the first isolation of B. henselae from a dog with fever of unknown origin. This observation contributes to the “One Health” concept focusing on zoonotic pathogens emerging from companion animals. A 1-year-old female German shepherd dog was referred for evaluation of fever of unknown origin of 1 month duration. Diagnostic investigations confirmed diffuse pyogranulomatous lymphadenitis. The dog became afebrile, and lymph node size normalized in response to a 6-week course of doxycycline. Retrospectively, Bartonella DNA was amplified from an EDTA-anticoagulated blood sample obtained before antimicrobial therapy, with the gtlA fragment sharing 99 % identity with the 350-bp gtlA fragment of the B. henselae Houston-1 strain. The same strain was isolated in the blood of three healthy cats from the household. Two months after discontinuation of doxycycline, the dog experienced a febrile relapse. Bartonella DNA was again amplified from blood prior to and immediately after administration of a 6-week course azithromycin therapy. However, without administration of additional medications, PCR was negative 9 months after azithromycin therapy and the dog remains clinically healthy 12 months following the second course of antibiotics. The medical management of this case raises several clinically relevant comparative infectious disease issues, including the extent to which Bartonella spp. contribute to fever of unknown origin and pyogranulomatous inflammatory diseases in dogs and humans, and the potential of doxycycline and azithromycin treatment failures. The possibility that dogs could constitute an underestimated reservoir for B. henselae transmission to people is also discussed. 相似文献
87.
88.
Favre R Duchange N Vayssière C Kohler M Bouffard N Hunsinger MC Kohler A Mager C Neumann M Vayssière C Viville B Hervé C Moutel G 《Prenatal diagnosis》2007,27(3):197-205
OBJECTIVES: To evaluate the level of information and informed consent for maternal serum screening (MSS) for Down syndrome (DS) in the second trimester of pregnancy and analyse the exercise of autonomy towards the test by the women concerned. METHODS: We studied the population of pregnant women attending obstetric consultations in two French hospitals over a 3-month period. The women were assigned to three groups according to MSS results for DS: women at high risk of having a child with DS (group 1), women at low risk (group 2) and women who did not undergo the test (group 3). A questionnaire was completed before the medical consultation, to assess the quality of consent before amniocentesis for the group at high risk and before the second-trimester ultrasound scan for the other two groups. RESULTS: We analysed 305 questionnaires for 89, 137 and 79 women belonging to groups 1, 2 and 3 respectively. In total, 123 women (40.3% [IC 95%, 35-46%]) were considered to be well informed; 33 (10%, [IC 95%, 8-12%]) had a high level of knowledge, but made choices not consistent with their stated attitude, and 149 (49.7% [IC 95%, 45-56%]) were considered uninformed. Logistic regression analysis showed that maternal consent depended on three independent components: The score attributed to the doctor for information about MSS (t = 4.216, p < 0.001).Whether the patient belonged to group 1 (t = -2.631, p < 0.009).Educational level (< high-school diploma, high-school diploma or at least two years of higher education after high school) (t = 2.324, p < 0.02). The rate of consent increased with educational level and was highest for the women in group 1 and for those whose doctor had a high information score. CONCLUSIONS: Our findings clearly show that women are provided with insufficient information concerning MSS screening for DS in the second trimester of pregnancy for real and valid consent to be obtained. 相似文献
89.
Alexandre Staub Muriel Scherer Pascal Zehnder Adriaan Bernardus Spierings Konrad Wegener 《Materials》2022,15(7)
In recent years, the advancement of technology brought the laser powder bed fusion process to its industrialisation step. Despite all the advancements in process repeatability and general quality control, many challenges remain unsolved due to the intrinsic difficulties of the process, notably the residual stresses issue. This work aimed to assess the usability of Barkhausen noise analysis (BNA) for the residual stress in situ monitoring of laser powder bed fusion on Maraging steel 300 (18Ni-300/1.2709). After measuring the evolution of grain size distribution over process parameter changes, two series of experiments were designed. First, a setup with an external force allows to validate the working principle of BNA on the chosen material processed using LPBF. The second experiment uses on-plates samples with different residual stress states. The results show a good stability in microstructure, a prerequisite for BNA. In addition, the external load setup acknowledges that signal variation correlates with the induced stress state. Finally, the on-plate measurement shows a similar signal variation to what has been observed in the literature for residual stress variation. It is shown that BNA is a suitable method for qualitative residual stresses variation monitoring developed during the LPBF process and underlines that BNA is a promising candidate as an in situ measurement method. 相似文献
90.
Laroche M Lemaire O Bourin P Corre J Gadelorge M Roussel M Attal M 《European journal of haematology》2012,88(5):388-395
Objectives: To evaluate the effect of high‐dose chemotherapy (HDT) followed by autologous stem cell transplantation (ASCT) on bone turnover and bone mineral density in a cohort of 39 consecutive patients with multiple myeloma (MM). Methods: Phosphorus and calcium parameters, bone turnover markers, and bone mineral density were studied. Timepoints were diagnosis (T1), just before ASCT (T2), 6 months (T3) after ASCT, and 1 yr (T4) after ASCT. Results: No bone mineral loss was shown on dual‐energy X‐ray absorptiometry (DXA) at T1 (lumbar Z‐score ?0.02, femoral neck Z‐score 0.77) or during follow‐up. Chronic vitamin D deficiency (25OHD3 11.7 ± 7.7 ng/mL at T1) and relative hyperparathyroidism from T2 to T4 were observed. In spite of this moderate hyperparathyroidism, serum C‐telopeptide of type I collagen (CTX) decreased significantly between T1 and T4. Bone alkaline phosphatase levels were low at diagnosis and showed no significant change after ASCT, unlike DKK1 levels that were high at diagnosis and decreased 6 months after ASCT in patients not previously treated with bisphosphonates. Conclusion: Bone demineralization is moderate in multiple myeloma. ASCT induces a decrease in bone resorption but no changes in bone formation, remaining low despite the decrease in DKK1. Bone mineral loss, evaluated by DXA, is moderate in multiple myeloma. High‐dose chemotherapy followed by ASCT leads to decreased bone resorption but osteoblastic bone formation remains low, in spite of reduced circulating DKK1. 相似文献