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1.
This article reports findings from a longitudinal survey of very elderly people living at home in London. The research aimed to identify social, psychological and physical characteristics associated with positive ageing and successful survival in the community in later life and its converse—negative ageing—as well as the associated policy implications. Associations with psychiatric morbidity, measured using the General Health Questionnaire, among sample members without cognitive impairment between the baseline interviews in 1987 and at follow-up, two and a half years later in 1990, are reported. Twenty-five per cent of survivors scored over the threshold of the GHQ in 1987 and 30% scored over the threshold in 1990. Half of those with a score over the threshold in 1990 also scored over the threshold in 1987. Hierarchical regression (using residualized change analysis) was used to estimate the effects of the independent variables on changes in psychiatric morbidity. The most significant predictor of psychiatric morbidity (GHQ score) in 1990 was baseline GHQ score, followed by health and functional status scores. Health and functional status were also the strongest predictors of baseline (1987) GHQ scores. The uniqueness of the study lies in the collection of follow-up data on a sample of very elderly people, given that most surveys are corss-sectional and contain too few people aged 85+ to merit separate analysis. It contributes to the small body of literature on outcome of depression. The lack of consistent associations with recovery from psychiatric morbidity in the literature enhances the importance of studies aiming to identify factors associated with different outcomes.  相似文献   
2.
As new vaccines are developed there is increasing interest in reducing the number of injections given to children by combining vaccines in one syringe. We studied the safety and immunogenicity of Haemophilus influenzae type b-tetanus protein conjugate vaccine (PRP-T) administered at ages 2, 4 and 6 months mixed in the same syringe with DTP vaccine and its effects on the seroresponse to DTP vaccine. A group of 112 healthy 2-month-old infants received DTP-PRP-T or DTP-placebo mixed immediately before immunization in the same syringe. The addition of PRP-T to DTP did not increase the rate of local or systemic reactions. After the first, second and third dose, the PRP-T recipients showed a geometric anti-PRP antibody mean of 0.13, 2.31 and 6.40 micrograms/ml vs. 0.07, 0.05 and 0.05 micrograms/ml among the DTP-placebo recipients, respectively. Of the PRP-T recipients, 94 and 98% attained antibody concentration of greater than or equal to 0.15 micrograms/ml protein after the second and third dose, respectively, and 65 and 94% attained a concentration of greater than or equal to 1.0 micrograms/ml after the second and third dose, respectively. At the age of 1 year 94 and 52% of the DTP-PRP-T recipients vs. 12% and 0% of the placebo recipients still maintained titers of greater than or equal to 0.15 and greater than or equal to 1.0 micrograms/ml, respectively. The administration of DTP in the same syringe with PRP-T did not affect significantly the antibody response to diphtheria and tetanus toxoid and to pertussis agglutinins. It is concluded that PRP-T vaccine could be administered in the same syringe as DTP.  相似文献   
3.
An RT-PCR/ELISA system has been developed that detects and differentiates Rinderpest virus (RPV) from the other closely related morbillivirus of ruminants, Peste des petits Ruminants virus (PPRV). In addition, using lineage specific probes, it is possible to determine whether the virus sample is wild-type or vaccine, and the likely origin of the outbreak if it is wild-type. It involves carrying out a RT-PCR with one digoxygenin (Dig)-labelled primer followed by a hybridisation step with a virus-specific, biotin-labelled, probe. The hybridisation step is carried out in an ELISA format on a streptavidin-coated plate. The DIG-labelled products are detected using a specific anti-DIG monoclonal antibody and an anti-mouse horseradish peroxidase conjugate. The hybridisation step replaces nucleotide sequencing or nested PCR for confirmation of the identity of DNA product. The assay is fast and easy to carry out and can give semi-quantitative estimates of the virus content of samples.  相似文献   
4.
During the Spring of 1986, 118 pupils aged 15-18 years were surveyed for the presence of humoral antibodies to five influenza strains. Prevalence of humoral immunity (HI) antibodies and immunity was found to be related to the year of the strain's emergence and to length of circulation time in the community. A high percentage of the adolescents were not immune to one or more of the tested strains. More than 40% of the studied group were not immune to the old A strains A/Philipines 2/82 (H3N2) and A/Chile 1/83 (H1N1), nearly 70% were not immune to the two B strains (B/USSR 100/83 and B/Ann Arbor 1/86), and almost the entire group (96%) was unprotected against the recent strain A/Singapore 6/86. Only one pupil was immune to all five strains; 35.6%, 22.2%, 17.8%, and 9.2% were immune to one, two, three, or four of the strains, respectively; and 14.4% were not immune to even one strain.  相似文献   
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