卫生应急人员对突发事件风险评估的认知分析

目的 :了解我国卫生应急人员对突发公共卫生事件风险评估的认知状况,从文化程度、职称情况、单位性质、单位级别等方面进行比较,为提高卫生应急人员风险评估的认识和能力提供依据。方法 :采用问卷调查的方法,对全国(大陆地区)31个省(自治区、直辖市)承担突发公共卫生事件应急处置的卫生应急工作人员进行调查。采用描述性分析和χ2检验对调查数据进行分析。结果 :我国卫生应急人员对风险评估概念熟悉程度较低,且不同学历、不同职称、不同工作年限、不同机构、不同层级之间的认知存在一定差异;对风险评估工作内容的认知也存在分歧。结论 :应加强风险评估培训,健全风险评估制度,以全面提高卫生应急人员对风险评估的认知水平。     

Leukocyte depletion enhances cultured endothelial retention on vascular prostheses

Approximately 90% of endothelial cells that are seeded or cultured onto vascular prostheses are lost from the flow surface within 24 hours of implantation. To determine the contribution of leukocytes to endothelial cell loss, 111In-labeled, cultured canine jugular venous endothelial cells were grown to confluence on fibronectin-coated polyester elastomer tubes measuring 4 mm inner diameter and 30 mm in length. Autogenous cell-lined tubes were implanted as bilateral carotid replacement grafts in six dogs made leukopenic by cyclophosphamide. Similar unilateral grafts were placed in 12 control dogs. Grafts were removed and perfusion-fixed from six control animals after 2 hours of in vivo arterial perfusion and from the other six animals after 6 hours of perfusion. One graft was removed and perfusion-fixed from each leukopenic animal after 2 hours of implantation and the other after 6 hours. Attachment of endothelial cells to the grafts was measured by indium-labeling technique. Retention of endothelium on grafts removed after 2 hours was measured by planimetric counting with scanning electron microscopy and on those removed after 6 hours by radioisotope quantification. Endothelial cell retention after 2 hours was 37.6% +/- 27.0% in control dogs and 97.0% +/- 3.4% in leukopenic animals (p less than 0.0007). After 6 hours retention was 35.9% +/- 23.2% in control animals and 86.5% +/- 6.0% in leukopenic animals (p less than 0.0009). Leukocyte surface activity was present in less than 1% of the leukopenic dogs compared with 8.5% of the other in vivo midgrafts after 2 hours. These results suggest that leukocytes play a significant role in the loss of seeded endothelium from vascular prostheses.     

耳穴贴压治疗单纯性肥胖症临床研究

目的探讨耳穴贴压治疗单纯性肥胖症的临床效应。方法应用耳穴贴压治疗单纯性肥胖症，观察治疗前后患者肥胖指标、血脂指标等的变化，评测耳穴贴压减肥的效果。结果各项指标在治疗前后差异均有显著性。结论耳穴贴压治疗单纯性肥胖，疗效确切，对患者各项生理指标有良性调节作用。     

Population immunity to polioviruses among preschool children from four urban underserved low income communities, United States, 1997-2001

BACKGROUND: In 1997, the Advisory Committee for Immunization Practices (ACIP) recommended a change in polio vaccination policy, the first in 30 years, from the oral poliovirus vaccine (OPV) to a combined OPV/inactivated poliovirus vaccine (IPV) sequential schedule for routine childhood vaccination. To evaluate the impact of the change in polio vaccination schedule on population immunity, we conducted a seroprevalence survey among low income preschool children from selected urban areas. METHODS: A repeat cross-sectional serosurvey was conducted during 1997-2001. Children 19-35 months of age receiving well-child care were recruited from outpatient clinics of academic medical centers. Serum samples were obtained and tested for neutralizing antibodies to polioviruses types 1, 2 and 3. A standardized questionnaire was administered to the parents or guardians of enrolled children. RESULTS: Seroprevalence remained high and stable during the study period. Among children sampled in the last study year (initiating their vaccinations from August 1997 through September 2000), seroprevalence was >/=95% to poliovirus serotypes 1 and 2 and >/=94% to serotype 3. Overall coverage with >/=3 doses of polio vaccine was 82-95% across sites during this period. The proportion initiating their vaccination schedule with IPV increased from 2.6% in study year 1 (children born October 1994-January 1997) to 80% in study year 4 (children born October 1997-January 2000). CONCLUSIONS: Children in these underserved low income communities are well-protected against the spread of polioviruses; the introduction of IPV did not adversely impact coverage or seroprevalence. Continued monitoring is needed to evaluate population immunity in the absence of OPV circulation.     

松质骨中两种纵波的传播特性分析

基于松质骨的层状模型，利用Schoenberg理论分析了松质骨中两种纵波(快纵波和慢纵波)的传播特性；并在理论和实验上详细分析了骨小梁方向与传播方向间的夹角对松质骨中快纵波和慢纵波传播特性的影响。分析结果表明，当超声波平行于骨小梁入射时，松质骨中两种纵波都传播，入射角度在60度附近时，松质骨中两种纵波的相速度曲线有一个转折点，入射角度在60度以上，角度越大时，骨髓和骨小梁耦合得越紧，因此阻止了慢纵波的传播，而只有快纵波传播。