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1.
In present constrained economic circumstances, many governments have introduced or increased user charges for health services. This has been advocated by the World Bank, justified by reference to the raising of revenue, efficiency and, controversially, even the promotion of equity. This paper examines the impact of user charges on utilisation in the Ashanti-Akim district of Ghana since the introduction of charges in 1985. In many ways, user charges have been a success: in recovering fees and maintaining urban utilisation. However some advantages have not materialised because the health infrastructure has not changed adequately. More importantly, equity and affordability have been problematical. For some of the population, services are no longer affordable.  相似文献   
2.
The mapping of 5-HT2 receptors in the brain using functional imaging techniques has been limited by a relative lack of selective radioligands. Iodine-123 labelled 4-amino-N-[1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl]-5-iodo-2-methoxybenzamide (123I-5-I-R91150 or123I-R93274) is a new ligand for single-photon emission tomography (SPET), with high affinity and selectivity for 5-HT2A receptors. This study reports on preliminary123I-5-I-R91150 SPET, wholebody and blood distribution findings in five healthy human volunteers. Maximal brain uptake was approximately 2% of total body counts at 180 min post injection (p.i.). Dynamic SPET sequences were acquired with the brain-dedicated, single-slice multi-detector system SEM-810 over 200 min p.i. Early peak uptake (at 5 min p.i.) was seen in the cerebellum, a region free from 5HT2A receptors. In contrast, radioligand binding in the frontal cortex increased steadily over time, up to a peak at approximately 100–120 min p.i. Frontal cortex-cerebellum activity ratios reached values of 1.4, and remained stable from approximately 100 min p.i. onwards. Multi-slice SPET sequences showed a pattern of regional variation of binding compatible with the autoradiographic data on the distribution of 5-HT2A receptors in (cerebral cortex>striatum>cerebellum). These findings suggest that123I-5-I-R91150 may be used for the imaging of 5-HT2A receptors in the living human brain with SPET.  相似文献   
3.
The effects of agonist and antagonist compounds on the equilibrium binding of the D1 antagonist ligand [3H]SCH 23390 were examined in membranes from the striatum of the rat. The antagonist SK&F 83566 interacted with D1 receptors in the manner of a competitive antagonist, causing a decrease in the affinity of the binding of [3H]SCH 23390, without altering the maximum number of binding sites (Bmax). The interaction of agonist compounds with the D1 receptor appeared to be more complex. The drug SK&F 75670, a weak partial agonist, also acted competitively at D1 sites. However, agonists with moderate (SK&F 38393, CY 208-243) or full (dopamine) intrinsic activity to stimulate adenylate cyclase, interacted with D1 binding sites in a mixed competitive/non-competitive manner, causing both a decrease in ligand affinity and a decrease in Bmax. The benzazepine analogue, which also has full agonist activity, SK&F 82958, only caused a reduction in Bmax. Furthermore, there was a positive relationship between the intrinsic activity of agonists and the magnitude of the reductions in Bmax which they induced. In the presence of the GTP analogue, Gpp(NH)p, CY 208-243 no longer caused an apparent reduction in the number of receptors. These data suggests that the apparent loss of D1 receptors, induced by agonists, may result from an interaction with a guanine-nucleotide sensitive, high affinity agonist binding site and that the degree of interaction with this site depends on the intrinsic D1 activity of the agonist.  相似文献   
4.
5.
This article summarizes the rationale, methods, and results of gene discovery programs in schizophrenia research and describes functional methods of investigating potential candidate genes. It focuses next on the most prominent current candidate genes and describes (1) evidence for their association with schizophrenia and research into the function of each gene; (2) investigation of the clinical phenotypes and endophenotypes associated with each gene, at the levels of psychopathologic, neurocognitive, electrophysiologic, neuroimaging, and neuropathologic findings; and (3) research into the ethologic, cognitive, social, and psychopharmacologic phenotype of mutants with targeted deletion of each gene. It examines gene-gene and gene-environment interactions. Finally, it looks at future directions for research.  相似文献   
6.
A distinctive feature of these workshops, in addition to those noted in the introductory overview, is the selection of a relatively isolated location for a 1-week period. This, together with a rich and varied program and an ethos of informality, encourages participants to discuss not only the work presented but also their unpublished work and their intuitions based on preliminary data and analyses. Such an interchange is of inestimable value to the schizophrenia research community. In scientific terms, a panel of concluding discussants (Drs Kendell, Torrey, and Waddington) were in some measure of agreement that genetics, particularly molecular genetics, appears to be experiencing a period of retrenchment, while epidemiology is experiencing something of a renaissance. Maternal influenza was a prominent theme, although the data were far from consistent. It was argued by Dr Wessely that risk for schizophrenia putatively attributable to maternal influenza might be 5% to 10% of all cases, indicating a modest effect. Eclectically, Dr Kendell believed the effect to be "real" but slight and fragile, it being sought against large aggregates that almost inevitably result in differing findings from differing countries or from different data bases within a given country. Gender differences were also among the more prominent themes, not just in an epidemiologic context but also in a variety of other studies. This points anew to disturbances in schizophrenia of factors that regulate, or are intimately associated with, sexual dimorphism in brain development. Abnormalities in cerebral asymmetry continue to pervade a variety of research findings and point further to neurodevelopmental anomalies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
The D-amino acid oxidase (DAO) signaling pathway has been implicated in schizophrenia pathogenesis. This may be mediated through modulation of NMDA function by DAO, which is in turn activated by DAO activator (DAOA, formerly G72). Chumakov et al. (2002); PNAS 99: 13675-13680, identifying the novel schizophrenia susceptibility gene DAOA/G30 and a number of independent studies have since reported evidence of association between the DAOA and DAO genes and schizophrenia. However, at least two studies have failed to replicate the epistatic interaction between these loci described in the original report and there have been differences in the associated alleles/haplotypes reported at each locus. In this study, we performed association and epistasis analyses of the DAOA/G30 and DAO loci in a sample of 373 cases with DSM-IV schizophrenia/schizoaffective disorder and 812 controls from the Republic of Ireland. Corrected for the number of tests performed, we found evidence for association between markers at both genes and schizophrenia: DAOA/G30 (P = 0.005, OR = 1.34 (1.09, 1.65)) and DAO (P = 0.003, OR = 1.43 (1.12, 1.84). The data suggest that evidence for association at DAO (marker rs2111902) is more consistent than previously realized, particularly in Caucasian schizophrenia populations. We identified evidence for epistatic interaction between the associated SNPs at DAOA and DAO genes in contributing to schizophrenia risk (OR = 9.3 (1.4, 60.5). Based on these data, more systematic investigation of genes involved in DAO signaling is required.  相似文献   
8.
Because identification of the species within the "Streptococcus milleri" group is difficult for the clinical laboratory as the species share overlapping phenotypic characteristics, we wished to confirm biochemical identification with identification by 16S rRNA gene sequence analysis. Ninety-four clinical isolates previously identified as the "Streptococcus milleri" group were reclassified as S. anginosus, S. constellatus, or S. intermedius with the API 20 Strep system (bioMerieux Vikek, Hazelton, Mo.) and the Fluo-card (Key Scientific, Round Rock, Tex.). In addition, we determined the Lancefield group, hemolysis, colony size, colony texture, repetitive extragenic palindromic PCR (rep-PCR) pattern, and cellular fatty acid (CFA) profile (MIDI, Newark, Del.). 16S rRNA gene sequence analysis with 40 selected representative strains showed three distinct groups, with S. constellatus and S. intermedius found to be more closely related to each other than to S. anginosus, and further distinguished a biochemically distinct group of urogenital isolates within the S. anginosus group of isolates. Except for strains unreactive with the Fluo-card (8%), all S. anginosus and S. intermedius strains identified by sequencing were similarly identified by biochemical testing. However, 23% of the selected S. constellatus isolates identified by sequencing (9% of all S. constellatus isolates) would have been identified as S. anginosus or S. intermedius by biochemical tests. Although most S. anginosus strains formed one unique cluster by CFA analysis and most S. constellatus strains showed similar rep-PCR patterns, neither method was sufficiently dependable for identification. Whereas Lancefield group or lactose fermentation did not correspond to sequence or biochemical type, S. constellatus was most likely to be beta-hemolytic and S. intermedius was most likely to have a dry colony type. The most frequent isolate in our population was S. constellatus, followed by S. anginosus. There was an association of S. anginosus with a gastrointestinal or urogenital source, and there was an association of S. constellatus and S. intermedius with both the respiratory tract and upper-body abscesses.  相似文献   
9.
In 1977 the Ministry of Health in Guinea Bissau started two regional community health projects. In this article we describe the progress of the Tombali project. Three aspects are discussed: the "Learning Process Approach" used in the project; measurement of the effectiveness of the project and the problems of collecting and interpreting these data; and the ratio of investment to recurrent costs and the proportions borne by government and by villagers. Primary health care projects evolve slowly, and the importance of the willingness of project workers, donor agencies, and the national government to work without a blueprint plan is emphasized. We discuss ways of evaluating the success of primary health care schemes; the measurement of any change in health status is difficult and discounts other benefits that may result, such as encouraging community participation and involving villagers in government activities. Both government and villagers contribute significantly to the scheme, the government and donors bearing most of the investment costs, while most of the recurrent costs fall on the villagers. The data show that for neither government nor villagers is the scheme a cheap option to secure health care for rural populations. Finally, we discuss the lessons to be learned by national governments, donor agencies, and health workers from this attempt to implement a primary health care program.  相似文献   
10.
Altered Phosphorylation of Rat Dentine Phosphoproteins by Fluoride In Vivo   总被引:2,自引:0,他引:2  
Dentine phosphoproteins have been proposed to have an important role in mineralization. This study focused on the influence of fluoride on the biochemical composition of dentine phosphoproteins and attempts to relate changes to the altered mineralization witnessed during fluorosis. Wistar rats were rendered fluorotic by the administration of 20 ppm sodium fluoride in their drinking water ad libitum, a nonfluorotic group received double-distilled, deionized water only. After 17 weeks, the teeth showed signs of fluorosis. The incisors were removed, split longitudinally, and the pulps were removed. Teeth were powdered and demineralized in 10% EDTA with protease inhibitors, after which the organic matrix was extracted with 4 M guanidinium chloride. Phosphoproteins were selectively precipitated from the soluble extract by the addition of 1.0 M calcium chloride and further purified by anion exchange chromatography. SDS-PAGE revealed two protein bands with molecular weights of 130 kDa and 66 kDa in the nonfluorotic fraction and 116 kDa and 66 kDa in the fluorotic fraction. Western blotting analysis identified the 66 kDa band as α2-HS glycoprotein which co-precipitated with phosphoproteins. Electroelution of the protein bands was performed with subsequent biochemical analyses. Phosphate content was determined for each protein band and was detectable in the 116 kDa and 130 kDa bands from the fluorotic and nonfluorotic samples, respectively, with a decreased level noted in the 116 kDa band. The presence of phosphate and the amino acid analysis of these bands suggested their identity to be dentine phosphoproteins. No changes in the ratio of amino acids was detected in fluorotic samples. The fluoride-induced alterations to the biochemical structure of dentine phosphoproteins would appear to influence the phosphorylation of these macromolecules only, possibly affecting posttranslational events. Such alterations may play a role in disrupting the patterns of mineralization seen during fluorosis. Received: 14 November 1997 / Accepted: 9 July 1998  相似文献   
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