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11.
中国人群DXS102座位多态性鉴定及其应用   总被引:13,自引:0,他引:13  
目的探讨中国人群中DXS102座位的多态分布。方法应用PCR扩增片段长度多态性(Amp-FLP)研究了无亲缘关系的234条X染色体。结果DXS102座位等位片段有8个,核心单元AC二核苷酸重复数为13~21,频率分布在0.013~0.156之间,杂合度观察值和无偏估测值分别为0.87和0.80,多态信息含量(PIC)0.80,女性基因型数为22个,男性基因型数为8个,该座位多态分布符合Hardy-Weinberg平衡定律。DXS102座位在中国人群和欧洲人群的分布有明显的种族差异,在中国人群中发现了两个新的等位片段。应用DXS102座位的短串联重复序列多态性对一接受基因治疗的血友病B家系进行分析和携带者筛查。结论DXS102座位连锁分析有望成为一种有效的血友病B基因诊断的方法。  相似文献   
12.
流感病毒血凝素基因工程抗体的抗病毒实验效果观察   总被引:1,自引:0,他引:1  
目的:对昆虫细胞系统表达纯化的中和性流感病毒血凝素基因工程全抗体IgG-IV-2,IgG-IV-6进行体外和体内抗病毒效果的研究。方法:对比抗体应用前后病毒在MDCK细胞中的病毒滴度和动物模型中粘膜用药前后鼠肺内病毒滴度的改变,验证抗体的粘膜抗感染效果。结果:两株基因工程抗体使4.5log10TCID50滴度的病毒下降1/2的剂量分别为0.8μg和0.5μg;动物模型的粘膜给药表明使4.0log10TCID50的病毒下降1/2所需的抗体剂量IgG-IV-2为0.25mg/kg体重,IgG-IV-6为0.1mg/kg体重,联合应用时为0.08mg/kg体重。结论:获得的基因工程抗体具有体内体外的抗病毒效果,能够中和病毒毒力。  相似文献   
13.
14.
人白细胞介素13cDNA的克隆及序列测定   总被引:1,自引:0,他引:1  
用反转录-多聚酶链反应(RT-PCR)技术从中国人外周血淋巴细胞中克隆了IL-13cDNA,序列测定表明克隆的IL-13cDNA含成熟的IL-13蛋白全部编码,且存在编码第98位Gln的密码子CAG,这为进一步表达IL-13并深入探究功能奠定了基础。  相似文献   
15.
目的 研究当药水提物对大鼠中性白细胞性细胞内内Ca^2 浓度增加、活性氧生成及兔血小板聚集的影响。方法 用酵母多糖、FMLP和A23 187活化大鼠中性白细胞,用化学发光法测定活性氧,用荧光光度法测细胞内Ca^2 浓度,用比浊法测血小板聚集。结果 当药水提物浓度依赖性地抑制酵母多精、FMLP和A23 187诱导的大鼠中性白细胞内Ca^2 浓度增加及活性氧生成;也抑制花生四稀酸、胶原及ADP诱导的兔血小板聚集。和吲哚美辛比较,当药水提物抑制活性氧生成的作用较强而抑制血小板聚集的作用较弱,其作用远强于swertiamarin。结论 当药水提物是极强的中性白细胞活性氧生成抑制剂,其作用强于swertiamarin。  相似文献   
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17.
ABSTRACT: BACKGROUND: Partner notification (PN) among individuals newly diagnosed with HIV/STI is seen as a vital tool to identify others at risk of infection. However, hardly any data are available on the effectiveness of PN on HIV/STI transmission in the Netherlands. This study aims to fill this gap by assessing current PN practices, case-finding effectiveness, and determinants of being notified among men having sex with men (MSM) in the Netherlands. METHODS: Nurses from five STI centers participated in a prospective pilot study on PN outcomes (partners being: at risk, notifiable, notified, and tested) for HIV/STI, by completing a newly developed PN registration form (PN database). PN outcomes including case-finding effectiveness (number of newly diagnosed cases in partners/number of partners being tested) for HIV, syphilis, and gonorrhoea were studied among MSM. Furthermore, the national STI database was analyzed to identify determinants of being notified. The number of infections that remained undetected was estimated based on these two databases. RESULTS: In total 105 MSM, newly diagnosed with HIV/STI, reported 612 sexual partners at risk of whom 41% were notifiable and 31% were notified. Patient referral was the predominant PN method (90%). The overall case-finding percentage was 36% (HIV: 15-33%, gonorrhoea: 17- 50% and syphilis: 4-11%). Case-finding percentages were lower in the national STI database: 21% (5%, 28%, 12%). Persons with one or more sexual partners, known HIV positives, and IDU were more likely to be notified to the STI clinic. Notified clients were more likely to have HIV/STI than unnotified clients (OR 1.7-2.5). Based on these two databases, an estimated 75 to 133 infections remained undetected (HIV: 12-90; gonorrhoea: 28-97; syphilis: 5-12 infections). CONCLUSIONS: Partner notification among MSM in the Netherlands is suboptimal; an extensive number of STI/HIV infections remained undetected mainly due to unnotifiable partners. To enhance PN practices, combined and innovative PN interventions such as Internet-based PN will be implemented for hard-to-reach MSM and other risk groups.  相似文献   
18.
The prognosis of the association between Breast Cancer (BC) and Meningioma (M) is unknown. To evaluate the survival impact of tumor exposure sequence in patients with both tumors. Patients were divided in groups according to the tumors sequence: BC before M (group 1), synchronous BC?+?M (group 2) and BC after M (group 3). The SEER database was used. Demographics, meningioma and breast cancer variables were analyzed. The primary outcome was oncological survival. A total of 1715 patients were included (median follow-up:84 months). Group 2 had the shortest survival (median:32 months) and group 1 the longest (median:110 months). On the unadjusted analysis, group 2 had the shortest survival (HR:3.13, 95% CI 1.62–6.04) and adjusted analysis confirmed this finding (HR 3.11, 95% CI 1.58–6.19), with no statistical difference between the metachronous tumors groups. Increasing age (HR:1.13, 95% CI 1.11–1.15, p?<?0.005) and grade III meningioma (HR:4.51, 95% CI 1.90–10.69, p?<?0.005) were related with lower survival. Meningioma treatment had no influence on the survival (p?>?0.05). The association between surgery and radiotherapy in BC treatment improved the outcome (HR 0.37, 95% CI 0.23–0.93, p?<?0.05). Grade III meningioma and receptor hormonal status influenced synchronous tumors (p?<?0.05) but had no influence on metachronous tumors survival (p?>?0.05) on stratified analysis. Synchronous tumors were associated with lower survival. Increasing age had a negative influence on patient survival. Although surgery and radiotherapy for breast cancer had a positive influence in the outcome, meningioma treatment was not related with survival. Grade III meningioma and hormonal receptor status only influenced synchronous tumors patient survival.  相似文献   
19.
目的 研究开发适合我国人群疾病特点且方便临床使用的心血管病发病危险度评估方法和评估工具。方法 依据中美心肺血管疾病流行病学合作研究队列随访资料,采用Cox比例风险模型拟合最优预测模型,并校正人群危险因素长期变化趋势的影响,采用独立人群回代检验和计算ROC曲线下面积来检验模型的预测能力。进一步建立简易预测模型,并据此制定适合我国人群的心血管病综合危险度简易评估工具。结果 中美心肺血管疾病流行病学合作研究1983~1984年基线调查年龄35~59岁,剔除基线患有冠心病、脑卒中及主要危险因素资料不全者后男女共计9903人,截止到2000年平均随访15.1年,共发生冠心病事件105例、缺血性脑卒中266例、缺血性心血管病360例。基线年龄、性别、血压、血清总胆固醇、体重指数、吸烟和糖尿病与冠心病、缺血性脑卒中和缺血性心血管病(ischemic cardiovascular diseases,ICVD)事件发病有互相独立的显著关联,且联系的方向和规律一致。据此建立的分性别ICVD事件10年发病危险预测模型,经过校正人群危险因素的长期变化趋势,证明能够很好地用于1992~1994年新建立队列的ICVD发病预测,其ROC曲线下面积(AUC)男性最优模型为0.799,女性最优模型为0.844。简易模型的AUC与最优模型几乎相同。结论 初步开发的ICVD事件10年发病危险预测模型和简易评估工具具有令人满意的预测能力,也能够较好地反映国人发生心血管病的综合危险。  相似文献   
20.

Purpose

Data on purpura fulminans (PF) in adult patients are scarce and mainly limited to meningococcal infections. Our aim has been to report the clinical features and outcomes of adult patients admitted in the intensive care unit (ICU) for an infectious PF, as well as the predictive factors for limb amputation and mortality.

Methods

A 17-year national multicenter retrospective cohort study in 55 ICUs in France from 2000 to 2016, including adult patients admitted for an infectious PF defined by a sudden and extensive purpura, together with the need for vasopressor support. Primary outcome variables included hospital mortality and amputation during the follow-up period (time between ICU admission and amputation, death or end of follow-up).

Results

Among the 306 included patients, 126 (41.2%; 95% CI 35.6–46.9) died and 180 (58.8%; 95% CI 53.3–64.3) survived during the follow-up period [13 (3–24) days], including 51/180 patients (28.3%, 95% CI 21.9–35.5) who eventually required limb amputations, with a median number of 3 (1–4) limbs amputated. The two predominantly identified microorganisms were Neisseria meningitidis (63.7%) and Streptococcus pneumoniae (21.9%). By multivariable Cox model, SAPS II [hazard-ratio (HR)?=?1.03 (1.02–1.04); p?<?0.001], lower leucocytes [HR 0.83 (0.69–0.99); p?=?0.034] and platelet counts [HR 0.77 (0.60–0.91); p?=?0.007], and arterial blood lactate levels [HR 2.71 (1.68–4.38); p?<?0.001] were independently associated with hospital death, while a neck stiffness [HR?0.51 (0.28–0.92); p?=?0.026] was a protective factor. Infection with Streptococcus pneumoniae [sub-hazard ratio 1.89 (1.06–3.38); p?=?0.032], together with arterial lactate levels and ICU admission temperature, was independently associated with amputation by a competing risks analysis.

Conclusion

Purpura fulminans carries a high mortality and morbidity. Pneumococcal PF leads to a higher risk of amputation.

Trials registration

NCT03216577.
  相似文献   
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