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1.
In 1998, the New York City Department of Health and the Mayor’s Office of Emergency Management began monitoring the volume of ambulance dispatch calls as a surveillance tool for biologic terrorism. We adapted statistical techniques designed to measure excess influenza mortality and applied them to outbreak detection using ambulance dispatch data. Since 1999, we have been performing serial daily regressions to determine the alarm threshold for the current day. In this article, we evaluate this approach by simulating a series of 2,200 daily regressions. In the influenza detection implementation of this model, there were 71 (3.2%) alarms at the 99% level. Of these alarms, 64 (90%) occurred shortly before or during a period of peak influenza in each of six influenza seasons. In the bioterrorism detection implementation of this methodology, after accounting for current influenza activity, there were 24 (1.1%) alarms at the 99% level. Two occurred during a large snowstorm, 1 is unexplained, and 21 occurred shortly before or during a period of peak influenza activity in each of six influenza seasons. Our findings suggest that this surveillance system is sensitive to communitywide respiratory outbreaks with relatively few false alarms. More work needs to be done to evaluate the sensitivity of this approach for detecting nonrespiratory illness and more localized outbreaks.  相似文献   
2.
A rapid and sensitive enzyme immunoassay (ELISA) was developed for the quantitation of anti-tetanus antibodies. This technique was used to measure antibody levels in the plasma of immunized donors, in human anti-tetanus IgG preparations and in human and mouse hybridomas producing monoclonal antibodies to tetanus toxoid. The assay was capable of detecting antibody levels as low as 5 X 10(-4) IU/ml. By inclusion of an extra step involving antibodies to mouse Ig isotypes, a sandwich enzyme immunoassay (SEI) was developed which permitted determination of the Ig isotype of mouse anti-tetanus antibodies including tetanus-specific mouse monoclonal antibodies. SEI confirmed Protein A-Sepharose fractionation of mouse ascites fluid containing anti-tetanus antibody. The tetanus toxoid-coated plates have a shelf life of at least 1 year.  相似文献   
3.
荧光定量PCR技术在检测HCV—RNA中的应用   总被引:1,自引:0,他引:1  
目的 评价荧光定量PCR技术测定HCV-RNA水平的价值,探讨PBMC中检出HCV-RNA的意义。方法 采用荧光定量KR及RT-PCR技术同时检测87例血液透析患者的血清和淋巴细胞中HCV-RNA。结果血清、淋巴细胞中HCV-RNA的荧光定量PCR检出率(49.4%、69.0%),分别高于相应标本中HCV-RNA的RT-PCR阳性率(33.3%、35.6%)(P <0.05)。血清、淋巴细胞中同时检出HCV-RNA的一致率,荧光定量PCR法(31.0%)显著高于RT-PCR定性法(6.9%)(P<0.001). 荧光定量PCR法,淋巴细胞中HCV-RNA检出率高于血清(P<0.01)。结论 与 RT-PCR相比,荧光定量PCR技术检测 HCV-RNA敏感性较高,对PBMC内HCV-RNA检测有利于提高HCV检测的阳性率。  相似文献   
4.
In cultured cells, KP544 [2‐amino‐5‐(4‐chlorophenylethynyl)‐4‐(4‐trans‐hydroxycyclohexyl amino) pyrimidine] amplifies differentiation initiated by nerve growth factor (NGF) or cAMP. This report describes the pharmacokinetics, safety, and neuroprotective efficacy of KP544 in rats. After an oral dose of 10 mg/kg KP544 was 25% bioavailable with a plasma half‐life of 1.3 h and brain levels 6‐fold higher than plasma levels at 4 and 8 h post‐dose. In a safety study, daily oral dosing for 30 days at 10 and 100 mg/kg was well tolerated. The favorable pharmacokinetic and safety profiles, together with its amplification of NGF in vitro, prompted evaluation of KP544 in two models involving NGF deficiencies. In the first model, brains were lesioned with intrastriatal injections of quinolinic acid. KP544 at oral doses of 0.02 to 1.0 mg/kg/day almost completely prevented the resulting learning deficits as evaluated using a radial‐arm‐water maze. At the lowest dose, there was a slower onset of functional improvement. These effects were accompanied by reductions (16–34%) in the striatal lesion size that were greatest at the highest dose and comparable to those seen with NGF therapy. The second model involved a peripheral neuropathy induced by taxol that is associated with decreases in NGF. KP544 at oral doses of 0.1–10 mg/kg/day decreased the severity of the neuropathy as measured by caudal nerve conduction velocities (30–70% return to control values). In both models, KP544 had a large therapeutic index suggesting its potential as a new approach for treating clinical disorders involving deficiencies in NGF. Drug Dev. Res. 62:60–70, 2004. © 2004 Wiley‐Liss, Inc.  相似文献   
5.
To inform New York City’s (NYC’s) tobacco control program, we identified the neighborhoods with the highest smoking rates, estimated the burden of second-band smoke exposure, assessed the early response to state taxation, and examined cessation practices. We used a stratified random design to conduct a digit-dialed telephone survey in 2002 among 9,674 New York City adults. Our main outcome measures included prevalence of cigarette smoking, exposure to second-hand smoke, the response of smokers to state tax increases, and cessation practices. Even after controlling for sociodemographic factors (age, racelethnicity, income, education, marital status, employment status, and foreign-born status) smoking rates were highest in Central Harlem and in the South Bronx. Sixteen percent of nonsmokers reported frequent exposure to second-hand smoke at home or in a workplace. Among smokers with a child with asthma, only 33% reported having a no-smoking policy in their homes. More than one fifth of smokers reported reducing the number of cigarettes they smoked in response to the state tax increase. Of current smokers who tried to quit, 65% used no cessation aid. These data were used to inform New York City’s smoke-free legislation, taxation, public education, and a free nicotine patch give-away program. In conclusion, large, local surveys can provide essential data to effectively advocate for, plan, implement, and evaluate a comprehensive tobacco control program. Dr. Mostashari (the guarantor) made substantial contributions to the conception, design, and supervision of this paper, the analysis and interpretation of data, the drafting of the paper, critical revisions of the paper for important intellectual content, and the acquisition of data and funding for this research. Dr. Kerker made substantial contributions to the analysis and interpretation of data, the drafting of the paper and critical revisions of the paper for important intellectual content. Ms. Hajat made substantial contributions to the acquisition of data and critical revisions of the paper for important intellectual content. Dr. Miller made substantial contributions to the conception of this paper and critical revisions of the paper for important intellectual content. Dr. Frieden made substantial contributions to the conception, design, and supervision of this paper and critical revisions of the paper for important intellectual content.  相似文献   
6.
Many multiple sclerosis (MS) patients with normal pure tone threshold suffer from difficulties in their hearing especially speech perception in background noise, which is possibly because of incompetence of central auditory processing in this group. Three audiologic tests including gap in noise test (GIN), duration pattern sequence test (DPST) and word discrimination score (WDS) were used for comparing a number of aspects of central auditory processing between patients with MS and normal subjects. Approximate threshold and percent of correct answers in GIN test, percent of correct answers in DPST test and monosyllabic discrimination in WDS test were obtained through cross-sectional non-invasive study conducted on 26 subjects with relapsing-remitting multiple sclerosis who had mean age of 28.9 (SD 4.1) years, and 26 18–40-year-old ones with normal hearing and mean age of 27.7 (SD 5.2). Results of this study demonstrate increased approximate threshold and reduction of percent of correct answers obtained from GIN test in patients with multiple sclerosis (Pv = 0.0001). Furthermore in patients with MS, the average of correct answers in DPST was lower than normal subjects and finally performance of MS subjects in WDS test in quiet environment was correlated with GIN threshold (r = ?/624, Pr = /003). Results of the present study showed that patients with MS had defect in aspects of central auditory processing consisting of temporal resolution, auditory pattern and the memory for auditory task and difficulty in discrimination of speech in noisy environment that are related to the involvement of central nervous system.  相似文献   
7.
The objective of the study is to provide information about non disease specified outcome measures which evaluate disability in patients who have impairments in hand and upper extremity and to find the extent to which they are evaluating “disability” based on ICF hand Core Set (activity limitation and participation restriction). MEDLINE, CINAHL, GOOGLE SCHOLAR , OVID and SCIENCE DIRECT databases were systematically searched for studies on non disease specified outcome measures used to evaluate upper extremity function; only studies written in English were considered. We reviewed titles and abstracts of the identified studies to determine whether the studies met predefined eligibility criteria (eg, non disease specified out come measures used in hand injured patients). All the outcome measures which had eligibility included. After full text review ,7 non disease specified outcome measures in hand were identified. Studies were extracted, and the information retrieved from them. All the outcome measures which had incuded, were linked with ICF hand core set disability part (activity and participation). All of them only linked to 16 (42 %) components of ICF hand Core Set, which were most activity and less participation from ICF. None of the non disease specified out come measures in hand injuries cover all domains of disability from the ICF Hand Core Set.  相似文献   
8.
9.
Sound knowledge of the anatomical patterns of lower limb vasculature is crucial for raising the free fibula flap (FFF). The tibial arteries are particularly susceptible to anatomical variations with a dominant role of peroneal artery (PR) for lower leg perfusion, and hence precluding fibular flap harvest. In this systematic review we study the prevalence of lower limbs with dominant peroneal artery (dPR). A systematic review of the MEDLINE and EMBASE databases was conducted using a comprehensive combination of keywords and search algorithm according to PRISMA guidelines. Articles describing the branching patterns of lower limb arteries, in cadaveric or angiographic studies, were included. A total of 5,790 limbs were included from 26 studies. dPR was found in 5.2% of all limbs. The combination of dPR with hypoplastic or aplastic posterior tibial artery was the most common pattern (3.3%) followed by hypoplastic anterior tibial artery (1.5%). Peronea arteria magna (PAM) was seen in 0.4% of limbs. Bilateral variants were seen in 20% of all cases with a dPR. A greater awareness of dPR as anatomical variation and its prevalence among healthy subjects can prevent ischemic donor‐site complications after FFF harvest. Clinical examination alone may not suffice to detect anatomical variations, hence preoperative imaging of lower limb vascular system is recommended. © 2015 Wiley Periodicals, Inc. Microsurgery 36:165–172, 2016.  相似文献   
10.
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