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The World Health Report 2000 on health systems has raised concerns about its political biases, its methods and indicators, and its lack of reliable data. Tracing the origins of the Report, this article argues that it counteracts many of the concerns that gave rise to preparation of the Report in the first place. The mutually agreed-upon value-base, expressed in the Health for All strategy, has been largely abandoned. The Report includes contradictory messages, and many of its recommendations are not evidence-based. Furthermore, the ranking of countries according to their health systems' performance is not useful for health-policy-making, even if the methods and data could be improved. Because the member states and governing bodies of the WHO were not consulted during the production of the Report, the WHO secretariat has not received a mandate to change the value-base of the WHO's health policy or the aims of the Report. The WHO should return to its mandate as a normative intergovernmental U.N. agency on health.  相似文献   
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We investigated the expression kinetics of several cytokines in trigeminal ganglia (TG) and in brains of BALB/c mice during the course of ocular herpes simplex virus type 1 (HSV-1) infection. All mice recovered from the infection within 2 weeks. The quantitative rapid real-time RT-PCR method was used to analyze interleukin-4 (IL-4), interferon-gamma (IFN-gamma), IL-12p35, IL-12p40, and the recently described IL-23 (p19) mRNA in TG, brain, and splenocyte samples. In TG, we found elevated expression of mRNA for IL-23 (p19) from early acute infection (day 3) to the beginning of the latent phase (day 14). The increase was not detected in brain or in the spleen. IL-4 expression occurred in both TG and brain from the beginning of the experiment to the latent phase. During the latent phase (days 14 and 31), IL-4 expression was significantly elevated in the brain when compared with the uninfected controls (p < 0.05). Considerable expression of IFN-gamma mRNA was detected in TG of mice during acute HSV-1 infection. The expression of IL-23 was detected also in the brains of the mice, even though no significant changes were found during the acute HSV-1 infection. This is, to our knowledge, the first report to show elevated expression of IL-23 (p19) mRNA (p < 0.05) during viral infection in TG of mice.  相似文献   
4.
Health has gained importance on the global agenda. It has become recognized in forums where it was once not addressed. In this article three issues are considered: global health policy actors, global health priorities and the means of addressing the identified health priorities. I argue that the arenas for global health policy-making have shifted from the public spheres towards arenas that include the transnational for-profit sector. Global health policy has become increasingly fragmented and verticalized. Infectious diseases have gained ground as global health priorities, while non-communicable diseases and the broader issues of health systems development have been neglected. Approaches to tackling the health problems are increasingly influenced by trade and industrial interests with the emphasis on technological solutions.  相似文献   
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In the periphery, B cells differentiate in germinal centres (GCs) of secondary lymphoid organs. Isolated GC cells die quickly in vitro by apoptosis. Therefore, cell lines originating from follicular lymphomas, which are the malignant counterparts of GC B cells, would provide a stable in vitro model to study the immunobiology of GC B cells. We have established three novel human follicular lymphoma cell lines that were characterized with special reference to immunophenotypic features, response to B-cell receptor (BCR) triggering, response to cytokines and cytokine mRNA expression. One of the cell lines, HF-1A3, has a phenotype of a centrocyte. It expresses surface immunoglobulin G (sIgG) and dies by apoptosis following BCR cross-linking. Co-stimulation with interleukin-6 (IL-6), IL-15 or interferon-gamma (IFN-gamma) rescues HF-1A3 cells from BCR-induced apoptosis. The second cell line, HF-28, also represents phenotypically an IgG+ centrocyte. Ligation of its BCR leads to the cell-cycle arrest at G1 instead of apoptosis. HF-28 cells express both CD45RA and RO isoforms, which is unusual in B lymphocytes apart from plasma cells, thus suggesting a transition to plasma cell phenotype. The third cell line, HF-4.9, which phenotypically represents an sIgM+ centroblast, responds by proliferation to BCR cross-linking. These cell lines offer a unique in vitro model to study antigenic selection and cytokine-mediated growth regulation of human GC B cells.  相似文献   
6.
Mutations in the BRCA1 and BRCA2 genes are known to predispose to breast cancer. In Finland, however, only 21% of all breast cancer families have mutations in these genes. Recent studies have shown that large genomic alterations of BRCA1 are common in many countries. Because such alterations will be missed in conventional mutation screening strategies, we decided to screen Finnish breast and ovarian cancer families for genomic alterations by using a multiplex polymerase chain reaction method. The most characteristic features of BRCA1-related breast cancer were used to select patients, namely (1) both breast and ovarian cancer in the family (48 patients), (2) four or more breast cancers in family (22 patients), or (3) young age (< or =40 years) of onset (58 patients). A total of 128 patients were included in the study. All exons of BRCA1 were analyzed but no alterations were found. This study excludes the frequent occurrence of large genomic alterations in the BRCA1 gene in Finland. Here, again, Finland differs from other countries with a mixed population structure. Our results are in agreement with the common hypothesis that there are still unknown breast cancer susceptibility gene(s) that are responsible for breast cancer predisposition.  相似文献   
7.
Reelin, an extracellular matrix protein has an important role in the migration, correct positioning and maturation of neurons during development. Though it is generally down-regulated in the postnatal period, expression of this large glycoprotein continues in the adult brain in some cell populations. In the present study, we examined the distribution of reelin-immunoreactivity (-ir) in the hippocampal formation of 9-month-old wildtype mice (WT). Then, reelin-ir in normal mice was compared to that of transgenic mice (APP/PS1) carrying mutated human APP and PS1 genes, which are linked to the familial form of Alzheimer's disease (AD). The APP/PS1 mice were additionally burdened with a second risk factor for AD, namely depletion of circulating gonadal hormones by ovariectomy (APP/PS1 + OVX). The analyses revealed that in adult WT reelin-ir is expressed by Cajal-Retzius cells and a subgroup of interneurons throughout the hippocampal formation. In addition, layer II projection neurons in the lateral entorhinal subfields are reelin-ir. Interestingly, ovariectomy decreases the number of reelin-ir cells in the hilus in WT mice, whereas AD-related genotype alone induces only a non-significant reduction. Unexpectedly, additional stress, e.g., depletion of gonadal hormones, does not aggravate the slight reduction in the reelin cell number in the APP/PS1 mice. We propose that the changes in normal reelin-ir are linked to disturbances in repair mechanisms in which APP/PS1 and gonadal hormones are involved and which are perturbed in neurodegenerative conditions, namely AD.  相似文献   
8.
Vascular endothelial growth factor (VEGF) is a hypoxia-inducible endothelial cell mitogen and survival factor. Its receptor VEGFR-2 (KDR/Flk-1) mediates these effects. We studied the expression of VEGF and VEGFR-2 in ischemic human and rabbit skeletal muscle by immunohistochemistry and in situ hybridization. Human samples were obtained from eight lower limb amputations because of acute or chronic critical ischemia. In chronically ischemic human skeletal muscle VEGF and VEGFR-2 expression was restricted to atrophic and regenerating skeletal myocytes, whereas in acutely ischemic limbs VEGF and VEGFR-2 were expressed diffusely in the affected muscle. Hypoxia-inducible factor-1alpha was associated with VEGF and VEGFR-2 expression both in acute and chronic ischemia but not in regeneration. Hindlimb ischemia was induced in 20 New Zealand White rabbits by excising the femoral artery. Magnetic resonance imaging and histological sections revealed extensive ischemic damage in the thigh and leg muscles of ischemic rabbit hindlimbs with VEGF expression similar to acute human lower limb ischemia. After 1 and 3 weeks of ischemia VEGF expression was restricted to regenerating myotubes and by 6 weeks regeneration and expression of VEGF was diminished. VEGFR-2 expression was co-localized with VEGF expression in regenerating myotubes. Macrophages and an increased number of capillaries were associated with areas of ischemic muscle expressing VEGF and VEGFR-2. In conclusion, two patterns of VEGF and VEGFR-2 expression in human and rabbit ischemic skeletal muscle are demonstrated. In acute skeletal muscle ischemia VEGF and VEGFR-2 are expressed diffusely in the affected muscle. In chronic skeletal muscle ischemia and in skeletal muscle recovering from ischemia VEGF and VEGFR-2 expression are restricted to atrophic and regenerating muscle cells suggesting the operation of an autocrine pathway that may promote survival and regeneration of myocytes.  相似文献   
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A novel composite material with an ultra-high strength and a low elastic modulus called carbon fibre-reinforced liquid crystalline polymer (LCP/CF) has been developed. An experimental diaphyseal osteotomy of the proximal femur in fourteen Beagle dogs was fixed with an intramedullary LCP/CF rod of 4.5 mm in diameter and 80 mm in length. The radiological follow-up intervals were 1, 3, 6, 12, 24, 52, and 104 weeks. Five dogs were killed at 1 year and three dogs at 2 years for histological studies; six dogs were retained for longer follow-up. Radiographs showed an uncomplicated healing of the diaphyseal osteotomy with an external callus formation in all dogs in 12 weeks. Histological analysis revealed a benign host tissue response with few inflammatory cells. Both bone and fibrous tissue were seen at the LCP/CF-host tissue interface. The cross-sectional cortical area of the operated femur was slightly greater than that of the control femur in the 2-year follow-up. LCP/CF showed promising properties for high-load applications.  相似文献   
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