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51.
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Summary Pyramidal neuron density was determined at autopsy in the brains of 12 neurologically normal patients (age range 6–87 years) and 18 patients with histopathologically confirmed Alzheimer's disease (AD; age range 62–89 years). Paraffin wax sections were cut at the level of the central part of the cornu ammonis and stained with cresyl fast violet. Pyramidal neuron density was determined in the stratum pyramidale of the presubiculum, subiculum, prosubiculum and CA1–4. The width of the stratum pyramidale in these areas was also determined. There was no significant effect of age on pyramidal neuron density in any of the fields of the hippocampal formation. However, there was a significant decrease in pyramidal neuron density in the subiculum (44%), prosubiculum (28%) and CA1 (41%) of AD brains compared to controls. There was no significant effect of AD on pyramidal neuron density in the presubiculum, CA2 and CA3, but in CA4 it increased (23%) significantly. Pyramidal band width decreased significantly with age in the presubiculum but there was no effect of age on any other region of the hippocampal formation investigated. The width of the stratum pyramidale was significantly lower in the presubiculum (19%), subiculum (30%) and CA3 (17%) of AD compared with control brains. These data suggest that a reduction in pyramidal neuron density within the hippocampal formation does not occur in the absence of underlying pathology. In AD, pyramidal neuron loss predominantly occurs from that sector of the hippocampal formation which comprises the subiculum, prosubiculum and CA1.Supported in part by MRC intercalated awards to N. H. and S. L. I. 相似文献
53.
The reasons for holding private medical insurance were studied in a sample of 495 insured Christchurch families having school aged children. In one-third of these families health insurance was provided by an employer. Two major reasons for holding insurance were cited by those whose insurance was not provided by an employer: three-quarters of these families stated that health insurance helped them meet medical bills and nearly two-thirds claimed that insurance provided them with access to immediate health care if this was needed. A minority (24%) of those holding health insurance believed that public sector services were inadequate to provide health care but only 9% of families were able to cite some specific shortcoming of public sector services which had impelled them to take out insurance cover. It is concluded that the rapid rise of private health insurance in New Zealand is likely to have arisen from the net effects of the promotional activities of insurance companies, the declining real contribution of State health care funding and the effects of growing public uncertainty about the ability of public sector services to deliver health care. 相似文献
54.
Interleukin-18 (Interferon-γ–inducing Factor) Is Produced by Osteoblasts and Acts Via Granulocyte/Macrophage Colony-stimulating Factor and Not Via Interferon-γ to Inhibit Osteoclast Formation 下载免费PDF全文
Nobuyuki Udagawa Nicole J. Horwood Jan Elliott Alan Mackay Jane Owens Haruki Okamura Masashi Kurimoto Timothy J. Chambers T. John Martin Matthew T. Gillespie 《The Journal of experimental medicine》1997,185(6):1005-1012
We have established by differential display polymerase chain reaction of mRNA that interleukin (IL)-18 is expressed by osteoblastic stromal cells. The stromal cell populations used for comparison differed in their ability to promote osteoclast-like multinucleated cell (OCL) formation. mRNA for IL-18 was found to be expressed in greater abundance in lines that were unable to support OCL formation than in supportive cells. Recombinant IL-18 was found to inhibit OCL formation in cocultures of osteoblasts and hemopoietic cells of spleen or bone marrow origin. IL-18 inhibited OCL formation in the presence of osteoclastogenic agents including 1α,25-dihydroxyvitamin D3, prostaglandin E2, parathyroid hormone, IL-1, and IL-11. The inhibitory effect of IL-18 was limited to the early phase of the cocultures, which coincides with proliferation of hemopoietic precursors. IL-18 has been reported to induce interferon-γ (IFN-γ) and granulocyte/macrophage colony-stimulating factor (GM–CSF) production in T cells, and both agents also inhibit OCL formation in vitro. Neutralizing antibodies to GM–CSF were able to rescue IL-18 inhibition of OCL formation, whereas neutralizing antibodies to IFN-γ did not. In cocultures with osteoblasts and spleen cells from IFN-γ receptor type II–deficient mice, IL-18 was found to inhibit OCL formation, indicating that IL-18 acted independently of IFN-γ production: IFN-γ had no effect in these cocultures. Additionally, in cocultures in which spleen cells were derived from receptor-deficient mice and osteoblasts were from wild-type mice and vice versa, we identified that the target cells for IFN-γ inhibition of OCL formation were the hemopoietic cells. The work provides evidence that IL-18 is expressed by osteoblasts and inhibits OCL formation via GM–CSF production and not via IFN-γ production. 相似文献
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Horwood C Vermaak K Butler L Haskins L Phakathi S Rollins N 《Bulletin of the World Health Organization》2012,90(3):168-175
Objective
To report the rates of mother-to-child transmission (MTCT) of the human immunodeficiency virus (HIV), and the coverage of interventions designed to prevent such transmission, in KwaZulu-Natal.Methods
Mothers with infants aged ≤ 16 weeks and fathers or legal guardians with infants aged 4–8 weeks who, between May 2008 and April 2009, attended immunization clinics in six districts of KwaZulu-Natal were included. The mothers’ uptake of interventions for the prevention of MTCT was explored. Blood samples from infants aged 4–8 weeks were tested for anti-HIV antibodies and, if antibody-positive, for HIV desoxyribonucleic acid (DNA).Findings
Of the 19 494 mothers investigated, 89·9% reported having had an HIV test in their recent pregnancy. Of the 19 138 mothers who reported ever having had an HIV test, 34.4% reported that they had been found HIV-positive and, of these, 13.7% had started lifelong antiretroviral treatment and 67.2% had received zidovudine and nevirapine. Overall, 40.4% of the 7981 infants tested were found positive for anti-HIV antibodies, indicating HIV exposure. Just 7.1% of the infants checked for HIV DNA (equating to 2.8% of the infants tested for anti-HIV antibodies) were found positive.Conclusion
The low levels of MTCT observed among the infants indicate the rapid, successful implementation of interventions for the prevention of such transmission. Sampling at immunization clinics appears to offer a robust method of estimating the impact of interventions designed to reduce such transmission. Large-scale elimination of paediatric HIV infections appears feasible, although this goal has not yet been fully achieved in KwaZulu-Natal. 相似文献57.
Myocardial protein kinases: I. Properties of soluble and membrane-bound catalytic subunits. 总被引:1,自引:0,他引:1
The particulate fraction of rat left ventricle, under certain specific assay conditions, was found to contain as much protein phosphotransferase activity as the soluble fraction. Both the soluble and the membrane-bound holoenzyme could be activated by cyclic AMP. The properties of the catalytic subunit of the soluble enzyme differed from those of the catalytic subunit of the particulate fraction with respect to substrate specificity and apparent KM values for ATP. The soluble enzyme was found to have a very low apparent KM for ATP (5.0 × 10?6m) and was inhibited by ATP concentrations above 0.2 mm. The particulate enzyme, on the other hand, showed a high apparent KM for ATP (1.3 × 10?4m) and the activity increased with increasing ATP concentrations up to 0.4 mm. The activities in the soluble and particulate fractions were observed to vary inversely between ATP concentrations of 0.1 mm and 0.4 mm. It is concluded that ATP concentration may play a role in controlling the activity of the catalytic subunit after its dissociation from the holoenzyme (by cyclic AMP binding to the regulatory subunit). 相似文献
58.
Pelosi F Oral H Kim MH Sticherling C Horwood L Knight BP Michaud GF Morady F Strickberger SA 《Journal of cardiovascular electrophysiology》2000,11(7):736-740
INTRODUCTION: The effect of oral amiodarone therapy on defibrillation energy requirements in patients with an implantable defibrillator has not been established. METHODS AND RESULTS: Twenty-one consecutive patients with implantable biphasic waveform defibrillators underwent a step-down determination of the defibrillation energy requirement 211 +/- 12 days before and 73 +/- 22 days after initiation of amiodarone therapy (mean total dose 26.7 +/- 11.1 g). Serum amiodarone and desethylamiodarone concentrations were measured at the time of defibrillation energy requirement determination. The mean defibrillation energy requirement before amiodarone therapy was 9.9 +/- 4.6 J. After initiation of amiodarone therapy, the mean defibrillation energy requirement increased to 13.7 +/- 5.6 J (P = 0.004). A linear relationship between the amiodarone (P = 0.02, r = 0.6), desethylamiodarone (P = 0.02, r = 0.6), and combined amiodarone-desethylamiodarone concentrations (P = 0.01, r = 0.6) and the defibrillation energy requirement was noted. Stepwise regression analysis demonstrated that the combined amiodarone-desethylamiodarone concentration was the only independent predictor of increase in the defibrillation energy requirement. CONCLUSION: Chronic oral amiodarone therapy increases the defibrillation energy requirement by approximately 62% in patients with an implantable defibrillator. The combined amiodarone-desethylamiodarone concentration is directly related to the increase in the defibrillation energy requirement. 相似文献
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