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OBJECTIVES--To define current clinical practice of lithium prescribing and monitoring and to compare hospital based practice with general practice. DESIGN--Prospective study of doctors'' practice. SETTING--Psychiatric hospital day and outpatient facilities and general practices in Edinburgh and Midlothian district (population 600,000). SUBJECTS--458 patients taking lithium who had been stabilised and who remained as outpatients during the year of study. 219 were treated by their general practitioner and 190 by the hospital; 49 had shared care or care transferred during the study. MAIN OUTCOME MEASURES--Daily dose, duration of treatment, psychiatric diagnosis, mean annual serum lithium concentration, frequency of occurrence of and response to raised serum concentrations. RESULTS--Compared with hospital doctors general practitioners were more likely to prescribe lithium three or more times daily (43/219 (general practice) v 10/190 (hospital); chi 2 = 18.6, p = 0.001) and to estimate serum concentrations less frequently (4.5 v 5.3 measurements/year; t = 3.04, p = 0.003), and their patients were more likely to experience raised lithium concentrations (39/219 v 17/190; chi 2 = 6.8, p = 0.01). One third of doctors made no response to raised lithium concentrations in the next six weeks. CONCLUSIONS--General practitioners and hospital doctors care for similar types of patients and the stringency of lithium surveillance varies greatly among doctors. Certain aspects of practice give cause for concern and could be improved by following more uniform guidelines. 相似文献
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The 1479-base pair (bp) nucleotide sequence of the serotype 5 M protein gene (smp5) from Streptococcus pyogenes contains three distinct types of tandemly repeated sequences, designated A, B, and C. Repeat A (21 bp x 6, in the 5'-half of smp5), shares no homology with the types 6 or 24 M protein genes (Hollingshead, S. K., Fischetti, V. A., and Scott, J. R. (1986) J. Biol. Chem. 261, 1677-1686; Mouw, A. R., Beachey, E. H., and Burdett, V. (1988) J. Bacteriol., in press). Repeat B (75 bp x 3.6, in the center of smp5) is also present in the M6, but not in the M24 gene. Repeat C (105 bp x 2.7, just distal to the B repeats) shares homology with repeats in both the M6 and M24 genes. All three genes share extensive homology in their 3'-halves and in 5' sequences encoding the N-terminal signal peptides, but between these two regions there are highly variable sequences that are responsible for antigenic diversity. These relationships suggest that both intergenic and intragenic recombination has occurred during the evolution of distinct M protein serotypes. All three M proteins contain conserved hydrophobic and proline-rich sequences at their C-terminal ends, suggestive of a membrane anchor and a peptidoglycan spanning region. 相似文献
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The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from
nucleotide sequence variation across a 765-bp region in the cytochrome
oxidase I and II genes of the mitochondrial genome. Most parsimonious
relationships of 25 haplotypes from 16 Greya species and two outgroup
genera (Tetragma and Prodoxus) showed substantial congruence with the
species relationships indicated by morphological variation. Differences
between mitochondrial and morphological trees were found primarily in the
positions of two species, G. variabilis and G. pectinifera, and in the
branching order of the three major species groups in the genus. Conflicts
between the data sets were examined by comparing levels of homoplasy in
characters supporting alternative hypotheses. The phylogeny of Greya
species suggests that host-plant association at the family level and larval
feeding mode are conservative characters. Transition/transversion ratios
estimated by reconstruction of nucleotide substitutions on the phylogeny
had a range of 2.0-9.3, when different subsets of the phylogeny were used.
The decline of this ratio with the increase in maximum sequence divergence
among taxa indicates that transitions are masked by transversions along
deeper internodes or long branches of the phylogeny. Among transitions,
substitutions of A-->G and T-->C outnumbered their reciprocal
substitutions by 2-6 times, presumably because of the approximately 4:1
(77%) A+T-bias in nucleotide base composition. Of all transversions,
73%-80% were A<-->T substitutions, 85% of which occurred at third
positions of codons; these estimates did not decrease with an increase in
maximum sequence divergence of taxa included in the analysis. The high
frequency of A<-->T substitutions is either a reflection or an
explanation of the 92% A+T bias at third codon positions.
相似文献
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