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This article reports one of the first studies of adult fears, specifically in an elderly population. Results indicated that older women expressed greater fearfulness than older men, a sex differential also observed in children and adolescents. When compared to other adult groups, significant differences were noted on several categories of fears. The elderly group ranked aging and sickness as their foremost fears, although the absolute degree of fearfulness did not differ from the comparison groups. Considered with previous investigations, these results suggest that some fears may change or intensify over the lifespan, and that within each period females report greater fearfulness than males. Additionally, this article describes a new entity, "fisity," which accounts for the popularity and the intensity of fears in a single measure.  相似文献   
74.
Ninety-eight patients with multiple sclerosis (MS) in the chronic progression phase entered a 3-year clinical trial to determine if azathioprine (AZ) alone or with adrenal cortical steroids stabilizes the course of MS. In group AM, the patients took AZ throughout and methylprednisolone (MP) for the first 36 weeks. Group AP received AZ and placebo instead of MP. Group PP took placebos for both drugs. We adjusted the AZ to maintain the total white blood cell count within 3,000 to 4,000/mm3; we gave the MP in a fixed dose "pulse" and alternate-day regimen. The "intent-to-treat" groups had no statistically significant differences in the rates of progression among the 3 treatments. Subgroup analysis suggests that patients in the AM group who completed treatment exactly according to protocol did statistically significantly better than the placebo recipients using the sum of Standard Neurological Examination scores, slightly better using the quantitative neuro-performance tests, but no better using Mickey's Illness Severity Scores or Kurtzke's Disability Status Scale. Also, the AZ-treated groups had half the relapse rate of the placebo-treated group. Adverse reactions to AZ accounted for most withdrawals. Hematologic and hepatic abnormalities were significantly associated with AZ, but serious non-MS abnormalities were uncommon and were equally distributed among the 3 groups. Addition of MP to the AZ slightly improved the efficacy of the treatment, but also increased the adverse effects. The benefits of AZ with or without steroids did not outweigh the risks, and therefore we do not recommend this treatment for patients with chronic progressive MS.  相似文献   
75.
The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages.  相似文献   
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77.
Inhibition of cellular transformation by the adeno-associated virus rep gene   总被引:17,自引:0,他引:17  
S N Khleif  T Myers  B J Carter  J P Trempe 《Virology》1991,181(2):738-741
  相似文献   
78.
The authors investigated factors that predict intention to take a genetic test for Alzheimer's disease (AD). The 449 men and women were surveyed in two groups: (a) those told that a positive result meant a 90% chance of developing AD (increased certainty) and (b) those told that a positive result meant a 50% chance of developing AD (decreased certainty). Participants completed measures of the Theory of Planned Behavior (TPB), anticipated regret, risk perception, likelihood of taking a genetic test for cancer, and AD risk factors. Just over 50% of the variance in intentions was related to TPB variables, likelihood of taking a genetic test for cancer, number of people the participants knew who had AD, experimental condition, and anticipated regret. The subjective norm was the strongest predictor of intention in the increased certainty group, whereas positive belief was the strongest predictor in the decreased certainty group.  相似文献   
79.
The numerical density of senile plaques (SP) and neurofibrillary tangles (NFT) as revealed by the Glees silver method was compared with SP and NFT revealed by the Gallyas method and with amyloid (A4) deposits in immunostained sections in 6 elderly cases of Alzheimer's disease. The density of NFT was generally greater and A4 lower in tissue from hippocampus compared with the neocortex suggesting that A4 deposition was less important than the degree of paired helical filament (PHF) related damage in the hippocampus. The density of Glees SP was positively correlated Gallyas SP weakly correlated with A4 deposit number. A stepwise multiple regression analysis which included A4 deposit and Gallyas SP density and accounted for 54% of the variation in Glees SP density. Hence, different populations of SP were revealed by the different staining methods. The results suggested that the Glees method may stain a population of SP in a region of cortex where both amyloid deposition and neurofibrillary changes have occurred.  相似文献   
80.
BACKGROUND—The GDNF family receptor alpha (GFRα) proteins are extracellular cell surface bound molecules that act as adapters in binding of the GDNF family of soluble neurotrophic factors to the RET receptor. These molecules are essential for development of many neural crest derived cell types and the kidney. Mutations in RET and in two members of the GDNF ligand family are associated with Hirschsprung disease (HSCR), a congenital absence of the enteric ganglia. Members of the GFRα family are also candidates for HSCR mutations. One such gene is GFRα-3, which is expressed in the peripheral nervous system and developing nerves.
OBJECTIVE—We have characterised the structure of the human GFRα-3 locus and investigated the gene for sequence variants in a panel of HSCR patients.
METHODS—Long range PCR or subcloning of PAC clones was used to investigate GFRα-3 intron-exon boundaries. A combination of single strand conformation polymorphism (SSCP) analysis and direct sequencing was used to investigate GFRα-3 sequence variants.
RESULTSGFRα-3 spans eight coding exons and has a gene structure and organisation similar to that of GFRα-1. We identified three polymorphic variants in GFRα-3 in a normal control population, a subset of which also occurred in HSCR patients. We did not detect any sequence variants within the coding sequence of GFRα-3. We found a base substitution in the 5' UTR of GFRα-3, 15 base pairs upstream of the translation start site. A second substitution was identified in intron 4 (IVS4-30G>A) between the splice branch site and the splice acceptor site. The final variant was a 2 base pair insertion within the splice donor consensus sequence of exon 7 (IVS7+4ins GG).
CONCLUSIONS—We did not detect any correlation between variants of GFRα-3 and the HSCR phenotype. Our data suggest that mutations of this gene are not a cause of HSCR.


Keywords: GFRα-3; Hirschsprung disease; RET  相似文献   
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