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101.
102.
Montserrat Agüero Isabella Monne Azucena Snchez Bianca Zecchin Alice Fusaro María Jos Ruano Manuel del Valle Arrojo Ricardo Fernndez-Antonio Antonio Manuel Souto Pedro Tordable Julio Cas Francesco Bonfante Edoardo Giussani Calogero Terregino Jesús Javier Orejas 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2023,28(3)
In October 2022, an outbreak in Europe of highly pathogenic avian influenza (HPAI) A(H5N1) in intensively farmed minks occurred in northwest Spain. A single mink farm hosting more than 50,000 minks was involved. The identified viruses belong to clade 2.3.4.4b, which is responsible of the ongoing epizootic in Europe. An uncommon mutation (T271A) in the PB2 gene with potential public health implications was found. Our investigations indicate onward mink transmission of the virus may have occurred in the affected farm. 相似文献
103.
中国大陆地区妇女骨质疏松筛选工具探讨 总被引:3,自引:0,他引:3
张菊英 吴涛 杨定焯 程晓光 周琦 卓铁军 张华寿 项静 王洪复 区品中 刘建立 徐苓 黄公怡 黄琪仁 Barden HS Weynand LS Fqukner KG 孟迅吾 《中国修复重建外科杂志》2007,21(1):86-89
目的建立适用于中国大陆地区40岁及以上妇女的骨质疏松(osteoporosis,OP)筛选工具。方法以20~39岁妇女腰椎骨密度的均数和标准差作为参考值计算T—score。以双能X线骨密度仪(dual—energy X—ray absorptiometry,DxA)的测量结果作为金标准,采用二分类的Bayes判别分析,建立判别函数。结果我国大陆地区40岁及以上妇女OP筛选工具(osteoporosis screening tool for Chinese,OSTC)为:体重-2×年龄+50。判别准则为OSTC〉0为无OP危险性,OSTC≤0为有OP危险性。OSTC的正判率为75.78%,灵敏度为76.8%,特异度为75.1%,Kappa值为0.51(P=0.000),说明OSTC与DXA的判定结果一致性尚可。结论OSTC是一个简便的OP筛选工具。根据年龄、体重两个变量的简单计算,即可对我国大陆地区40岁及以上的妇女进行OP危险性的筛选。但OSTC没有得到外部数据的验证,其优劣还有待进一步评价。 相似文献
104.
Studies on the structure of bovine factor V by scanning transmission electron microscopy 总被引:2,自引:0,他引:2
We studied purified bovine factor V (mol wt 330,000) by scanning transmission electron microscopy (STEM) of freeze-dried unstained or negatively contrasted preparations. Freeze-dried molecules revealed discrete shapes ranging from roughly spheroidal (100 to 120 nm) to oblong (140 to 200 nm in length X 50 to 100 nm in width). Oblong shapes could often be resolved into two or three distinct domains, ranging from 60 to 100 nm in diameter. A "satellite" nodular structure (30 to 50 nm in diameter) connected to the main molecule by a thin stalk (approximately 10 nm wide) up to 80 nm in length was occasionally seen. Glutaraldehyde-treated preparations yielded the same shapes as were seen in unfixed preparations but revealed better definition of submolecular features and "satellite" nodules. STEM mass analysis confirmed that each of the different shapes represented a monomolecular form of factor V. Negatively stained images revealed objects having the same general shapes as freeze-dried molecules, although greater detail was evident. Some images suggested that molecules consist of five or more discrete parts. Taken together, these observations indicate that factor V molecules are multidomainal, flexible structures that tend to have an irregular oblong shape with an axial ratio between 3:2 and 2:1. 相似文献
105.
Menopause, menstrual and reproductive history, and bone density in northern Italy. 总被引:2,自引:1,他引:2 下载免费PDF全文
F Parazzini E Bidoli S Franceschi D Schinella F Tesio C La Vecchia R Zecchin 《Journal of epidemiology and community health》1996,50(5):519-523
STUDY OBJECTIVE: To analyse the relationship between menstrual and reproductive factors and the risk of low bone mineral density (BMD). DESIGN: This was a population based screening programme carried out between 1991 and 1993 among 1373 perimenopausal women in northern Italy by means of dual photon absorptiometry at the lumbar spine. MAIN RESULTS: BMD was strongly related to the age at menopause. In comparison with women reporting menopause below 45 years of age, the odds ratios (OR) of being in the lowest compared with the highest BMD tertile were 0.7 (95% confidence interval (CI) 0.3,1.5) and 0.3 (95% CI 0.1,0.8), respectively, in those with menopause at age 45-49 and above 50 years: the trend in risk was significant. Likewise, the risk of being in the lowest tertile increased with years since the menopause. Compared with women who reported they had undergone the menopause less than two years before interview, the OR of being in the lowest BMD tertile were 2.1 (95% CI 1.1,4.3), 2.3 (95% CI 1.1, 5.0), and 5.7 (95% CI 2.5,12.9) respectively in women who reported menopause 2-5, 6-9, and > or = 10 years earlier. The protective effect on bone density of late age at menopause was observed in different strata of years since menopause. Likewise, the increasing risk of a low BMD with increasing years since the menopause was evident in strata of different age at menopause. No relationships were observed between BMD and the age at menarche, characteristics of menstrual cycles, and the duration of menses. Likewise, no association emerged between reproductive history, including parity and age at first pregnancy, and BMD. CONCLUSIONS: In this Italian population the risk of being in the lowest BMD tertile decreased with increasing age at menopause and increased with years since menopause. No relationships emerged between BMD and other menstrual characteristics or reproductive factors. 相似文献
106.
Blume KG; Kopecky KJ; Henslee-Downey JP; Forman SJ; Stiff PJ; LeMaistre CF; Appelbaum FR 《Blood》1993,81(8):2187-2193
Two novel preparatory regimens for conditioning of patients with leukemia for allogeneic bone marrow transplantation (BMT) from histocompatible sibling donors have been tested in a phase III trial under the auspices of the Southwest Oncology Group (SWOG 8612). These two regimens consisted either of fractionated total body irradiation and etoposide (FTBI/VP-16) or high-dose busulfan with cyclophosphamide (BU/CY). Only patients who had failed prior conventional management at least once were study eligible, ie, no patients with acute leukemia in first remission (CR) or in first chronic phase (CP) of chronic myelogenous leukemia (CML) participated. Patients were stratified according to the following risk criteria: "good-risk" patients were those who were in second CR of their acute leukemia or in accelerated phase (AP) of CML; "poor-risk" patients had further advanced stages of leukemia. During a 52-month period, 131 patients were registered of whom 122 (93%) were study eligible. Sixty-one eligible patients were randomized to the FTBI/VP-16 arm and 61 to the BU/CY regimen. Of these 122 patients, 114 (93%) proceeded to BMT according to protocol. Posttransplant immunosuppression to prevent graft-versus-host disease (GVHD) consisted of cyclosporine and prednisone (CSA/PSE). Neither overall survival nor disease-free survival (DFS) differed significantly between the two treatment groups (P = .89 and .69, respectively). Estimated DFS for "good-risk" patients who had been prepared with the FTBI/VP-16 regimen was 55% +/- 11%, as compared with patients treated with BU/CY whose DFS figure was 34% +/- 10% (P = .30). For "poor-risk" candidates, the DFS rates at 24 months were 17% +/- 6% (for FTBI/VP-16) and 24% +/- 8% (for BU/CY), respectively (P = .81). These figures do not differ significantly, especially in view of the fact that the "good- risk" patients prepared with the FTBI/VP-16 regimen were younger than those treated with BU/CY. Both regimens were well tolerated with no regimen-related deaths encountered during the 6-week period after BMT. This study also confirmed the efficacy of the CSA/PSE combination in the prevention of GVHD with 23 of 113 (20%) of BMT recipients developing moderate to severe acute GVHD. The leading cause for treatment failure was leukemic relapse (45 of the 114 BMT recipients suffered a recurrence of their leukemia), whereas 38 patients died without evidence of relapse. Thirty-one patients are alive and in continued CR after marrow transplantation; four are alive in relapse.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
107.
108.
刘学明 《吉林大学学报(医学版)》1994,(1)
本文以人红细胞(RBC)胞浆提取物为SSA抗原来源,探讨了免疫印迹法(IBT)检测抗SSA抗体的可能性及特点。结果显示,在RBC-IBT中有两条抗SSA(干燥综合征抗原)抗体特异性酶染色带,分子量分别为52KD和60KD。非特异性染色带极少或无。也未见其它几种常一自身抗体(抗SM、RNP、SSB等)的显色带。这说明RBC-IBT对抗SSA抗体的检测有高度的专一性和特异性,值得推荐。文中还就RBC-IBT法中主要的实验影响因素进行了探讨。 相似文献
109.
110.
A 68-year-old man, following mitral valve replacement, presented with a low-grade chronic consumptive coagulopathy. Laboratory analysis showed mild fibrinolysis, minimal effect of coumadin therapy, and a prolonged thrombin time (greater than 150 seconds using bovine IIa). When purified human IIa was used the thrombin time normalized to within 17 seconds of controls, suggesting a possible inhibitor of bovine IIa. An anti-IIa antibody was isolated by protein A-Sepharose (Sigma, St Louis, MO) chromatography followed by affinity chromatography using a bovine IIa-Sepharose column. The effects of this purified anti-IIa antibody on both bovine and human IIa procoagulant and anticoagulant functions were studied. The isolated immunoglobulin G (IgG) was observed to inhibit bovine IIa in all assays tested. This IgG was also able to slightly prolong fibrinogen clotting by human IIa. Using an enzyme-linked immunosorbent assay it was observed that the IgG bound to bovine IIa, bovine II, human IIa, but not to human II. Further, binding was detectable at approximately 50-fold lower concentrations to bovine IIa (1 nmol/L IgG concentration) than to human IIa (50 nmol/L IgG concentration). The effect of the antibody on the reaction between IIa and AT III/heparin was investigated. Human IIa was found to be protected from AT III/heparin neutralization in the presence of this antibody. These results suggest that this patient developed an antibody that strongly binds to and inhibits the bovine IIa in all assays tested. However, the antibody only significantly affects human IIa neutralization by AT III/heparin, and has little effect on the human IIa procoagulant activity. These data suggest that the decreased effect of AT III/heparin on this patient's IIa may have been a contributing factor in his coagulopathy. The exact cause of this antibody development is unclear, but the role of bovine topical thrombin used during cardiac valve replacement surgery is suspect. 相似文献