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131.
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The allelic frequency of the gene for the K variant of butyrylcholinesterase (BCHE-K) was 0.17 in 74 subjects with late-onset (age > 65 years) histopathologically diagnosed Alzheimer's disease (AD), which was higher than the frequencies in 104 elderly control subjects (0.09), in 14 early-onset cases of confirmed AD (0.07) and in 29 confirmed cases of other dementia (0.10). The association of BCHE-K with late-onset AD was limited to carriers of the epsilon 4 allele of the apolipoprotein E gene (APOE), among whom the presence of BCHE-K gave an odds ratio of confirmed late-onset AD of 6.9 (95% C.I. 1.65-29) in subjects > 65 years and of 12.8 (1.9-86) in subjects > 75 years. In APOE epsilon 4 carriers over 75 years, only 1/22 controls, compared with 10/24 confirmed late-onset AD cases, had BCHE-K. We suggest that BCHE-K, or a nearby gene on chromosome 3, acts in synergy with APOE epsilon 4 as a susceptibility gene for late-onset AD.   相似文献   
133.
创伤病人的手术与焦虑状态调查   总被引:6,自引:0,他引:6  
采用状态——特质焦虑问卷及10项躯体性焦虑测试题,对40例外科创伤病人手术前后的焦虑状态调查显示:术前状态焦虑量表评分显著高于术后;术前躯体性焦虑评分显著高于术后;高特质焦虑评分亚组与低特质焦虑评分亚组术前状态焦虑评分无显著差异,但术后则前者显著高于后者;急诊手术者手术前后状态焦虑评分显著高于择期手术者。  相似文献   
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BACKGROUND: The analysis of epidemic influenza virus has been focused on antigenic and genomic characterization of the hemagglutinin (HA) glycoprotein in order to detect new variants for the recommendation of the vaccine strains in each season. Since October 1998, WHO organized a second meeting to evaluate the vaccine formula for the southern hemisphere. OBJECTIVES: (a) Present the antigenic and genomic characterization of influenza strains obtained from the Argentina surveillance network, (b) compare between strains collected in Argentina and other countries with the vaccine formula strains used in each season. STUDY DESIGN: Influenza strains were collected during a 5-year period (1995-1999). Initially, laboratory diagnosis was done by immunofluorescence (IF) assay on clinical samples, followed by viral isolation in Madin-Darby canine kidney (MDCK) cells. The isolates were characterized antigenically by hemagglutination-inhibition (HI) assay with post-infection ferret antisera. The genomic characterization consisted on RT-PCR followed by sequencing of the HA1 portion of the HA gene. The comparison between reference and circulating strains was analyzed by the construction of phylogenetic trees. RESULTS: The H3N2 circulating strains matched the corresponding vaccine component only in 1999, the first year when a vaccine recommended specifically for the southern hemisphere was used. Besides, H1N1 circulating strains matched the corresponding vaccine component only in 1998. Regarding to influenza B, only in 1995, the circulating strains showed no match to the B vaccine component. CONCLUSIONS: The results showed the usefulness of an intensified influenza laboratory surveillance to access the correct vaccine and the importance of having the necessary tools to characterize the circulating strains.  相似文献   
136.
Human infection by a swine influenza A (H1N1) virus in Switzerland   总被引:2,自引:0,他引:2  
Summary.  The isolation of A/Switzerland/8808/2002 provides further evidence of sporadic human infection by contemporary swine influenza A H1N1 viruses, antigenically and genetically distinct from H1N1 viruses circulating in the human population. Together with the recent emergence of human-swine-avian reassortant viruses in pig populations in Europe and North America, frequent transmission between swine and human populations emphasises the potential for the emergence in pigs of novel subtypes with the capacity to cause major human epidemics. Received October 11, 2002; accepted November 8, 2002  相似文献   
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Because the risk factors for human immunodeficiency virus (HIV) infection and hepatitis B (HBV) are similar and therefore coinfection is not uncommon, a detailed histological and immunohistochemical study of chronic hepatitis B infection in a group of 20 HIV positive Caucasian males (who did not have AIDS) and 30 HIV negative controls were undertaken. Using both the conventional histological classification and the Knodell histological activity index it was shown that HIV negative patients were more likely to have active disease and also more scarring than HIV positive patients. Hepatitis B surface antigen (HBsAg) expression was not significantly different between the two groups but expression of hepatitis Be antigen (HBeAg) and HBV-DNA polymerase was greater in those who were HIV positive. HIV positive patients are therefore more likely to have immunohistochemical markers of active viral replication, although histologically, liver disease is less severe. These findings have important implications for assessing the biopsy specimens in this group of patients and for treatment strategies aimed at improving their immune function.  相似文献   
140.
Plasma levels of soluble T-suppressor/cytotoxic antigen (sCD8) were measured at diagnosis or before systemic treatment in 69 patients with hairy cell leukemia (HCL). The 49 nonsplenectomized patients were characterized by high concentrations of sCD8 antigen as compared with 17 controls (P less than .0001). The median sCD8 level in non- splenectomized patients was 1,050 U/mL (range: 160 to 2,400 U/mL) and was significantly higher (P less than .0001) than the median of 275 U/mL (range: 20 to 1,080 U/mL) in splenectomized patients. The relationship of sCD8 to clinical response to subsequent interferon alpha (IFN alpha) treatment was analyzed. Patients who showed subsequent hematologic response with normalization of all blood counts had significantly lower levels of sCD8 concentrations at diagnosis than those who did not (P = .0056). Furthermore, normalization of sCD8 during IFN alpha treatment paralleled the achievement of normal counts in peripheral blood, whereas soluble interleukin-2 receptor (sIL-2R) levels remained high in most patients after 12 to 15 months of treatment. We speculate that activation of suppressor/cytotoxic T cells might play a role in myelosuppression, and its modulation during treatment with IFN alpha correlates with normalization in peripheral blood counts.  相似文献   
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