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81.
A novel allele, human leukocyte antigen (HLA)-A*6824, has been identified in three unrelated individuals of northwestern European origin in a period of less than 4 months, implying that this allele may be quite common in this population. HLA-A*6824 differs from A*680102 by a single nucleotide change at position 275 in exon 2, which results in a conservative amino acid substitution from lysine to arginine in the peptide-binding groove at codon 68.  相似文献   
82.
We have identified a new HLA-B*15 allele (B*1569) by polymerase chain reaction (PCR) using sequence-specific primers (SSP) and sequence-based typing (SBT). This novel allele was found in a 67-year-old white Caucasian male and differs from HLA-B*1503 at 3 positions. The nucleotide substitutions at positions 544, 559 and 560 result in amino acid changes at codon 158 from GCC (alanine) to ACC (threonine), and at codon 163 from CTG (leucine) to ACG (threonine).  相似文献   
83.

Background  

Intervention time series analysis (ITSA) is an important method for analysing the effect of sudden events on time series data. ITSA methods are quasi-experimental in nature and the validity of modelling with these methods depends upon assumptions about the timing of the intervention and the response of the process to it.  相似文献   
84.
We describe the first documented field transmission of West Nile (WN) virus by a North American mosquito. WN was first detected in northern Florida in 2001. An intensive mosquito trapping and surveillance program was conducted in this region for four nights to assess mosquito transmission of WN. Four mosquito traps, each with a single sentinel chicken, were placed at five different locations on each of four nights. A total of 11,948 mosquitoes was collected, and 14 mosquito pools were found to contain WN, giving a minimum infection rate between 1.08 and 7.54 per 1,000. Only one of the 80 sentinel chickens seroconverted to WN, demonstrating a single mosquito transmission event during the study and a mosquito transmission rate of between 0.8 and 1 per 1,000. Culex nigripalpus Theobald was responsible for WN transmission to the sentinel chicken, although both Cx. nigripalpus and Culex quinquefasciatus Say were found infected with WN. Mosquito transmission rates are reported in this study for the first time for a WN outbreak. This information is essential to determine risk of human and animal infection.  相似文献   
85.
Use of multiepitope polyproteins in serodiagnosis of active tuberculosis   总被引:13,自引:0,他引:13  
Screening of genomic expression libraries from Mycobacterium tuberculosis with sera from tuberculosis (TB) patients or rabbit antiserum to M. tuberculosis led to the identification of novel antigens capable of detecting specific antibodies to M. tuberculosis. Three antigens, Mtb11 (also known as CFP-10), Mtb8, and Mtb48, were tested together with the previously reported 38-kDa protein, in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies in TB patients. These four proteins were also produced as a genetically fused polyprotein, which was tested with two additional antigens, DPEP (also known as MPT32) and Mtb81. Sera from individuals with pulmonary and extrapulmonary TB, human immunodeficiency virus (HIV)-TB coinfections, and purified protein derivative (PPD)-positive and PPD-negative status with no evidence of disease were tested. In samples from HIV-negative individuals, the ELISA detected antibodies in >80% of smear-positive individuals and >60% smear-negative individuals, with a specificity of approximately 98%. For this group, smears detected 81.6% but a combination of smear and ELISA had a sensitivity of approximately 93%. The antigen combination detected a significant number of HIV-TB coinfections as well as antibodies in patients with extrapulmonary infections. Improved reactivity in the HIV-TB group was observed by including the antigen Mtb81 that was identified by proteomics. The data indicate that the use of multiple antigens, some of which are in a single polyprotein, can be used to facilitate the development of a highly sensitive test for M. tuberculosis antibody detection.  相似文献   
86.
Rats with kainate-colchicine hippocampal lesions (HL) and controls (C) were initially trained in the Morris water maze with procedures that deterred their prepotent thigmotaxic response. Training began with an escape platform that occupied nearly the entire pool. The area to which the rats could escape was made smaller by substituting smaller platforms as training progressed. In contrast to standard procedures, HL rats and C rats showed comparable performance during acquisition and preferentially searched the goal quadrant on probe trials during which the platform was removed. In a follow-up experiment, the platform was moved to a random position along the wall, which required a switch to a thigmotaxic response for most effective escape. HL rats that were thigmotaxic before place training did not switch to a thigmotaxic response as readily as did controls, behavior consistent with the view that hippocampal damage reduces pliancy.  相似文献   
87.
Alcoholic cirrhosis is one of the most common indications for liver transplantation. Previous researchers have studied rates of return to drinking following transplantation, however, few have employed prospective measures of alcohol use. The authors prospectively studied the alcohol use of patients transplanted for alcoholic liver disease. The authors improved the accuracy of monitoring alcohol use by using various methods for tracking patient's alcohol consumption, and we report on the time to first alcohol use after transplantation comparing these different methods. The authors found that alcohol use can occur very early after transplantation, even within the first 3 months posttransplant. Thirty-eight percent of the patients consumed any alcohol after transplantation. The clinical interviews by the psychiatrist were the most successful method for identifying posttransplant alcohol use. Posttransplant alcohol use was significantly associated with prior nonalcohol substance use (P < 0.025), family history of alcoholism in a first-degree relative (P < 0.025), and prior alcohol rehabilitation experience (P < 0.05) but not with a prior psychiatric history or less than 6 months of pretransplant sobriety. The authors indicate that prospective monitoring, using a combination of methods, is the most accurate approach to identify alcohol consumption. With this type of accuracy, risk factors can be identified and alcohol use can be compared with alcohol-related morbidity posttransplant.  相似文献   
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目的:合成双-对二甲氨基苯甲醛缩二胺类希夫碱,并对其抗菌活性进行研究。方法:以对二甲氨基苯甲醛和二胺类为原料,经缩合反应,制得4种相应希夫碱。结果:结构经元素分析、红外光谱、核磁共振谱确定,4种化合物均未见文献报道,抗菌活性测试表明,它们具有一定抗菌活性。结论:乙酸是催化剂,对缩合反应有利,希夫碱化合物具有一定抗菌活性。  相似文献   
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