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排序方式: 共有926条查询结果,搜索用时 15 毫秒
1.
J Somerville 《British journal of hospital medicine》1990,43(2):132-136
'Grown-up' congenital cardiac patients are an increasing medical community, not at present being properly cared for in any country. Information on over 2000 patients aged 15-65 years with congenital heart disease who have been treated in the National Heart Hospital provides the data for this report. 相似文献
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OBJECTIVE: To ascertain the quality of analgesia provided by morphine in comparison to codeine. DESIGN: The study is a prospective, randomized, double-blind trial of analgesic effect employing validated pain scores. PATIENTS: Infants having primary cleft palate repair with informed parental consent to enter the study. INTERVENTIONS: Infants received one of two analgesics intraoperatively for immediate postoperative pain relief. Morphine was given by intravenous injection and codeine by the intramuscular route. MAIN OUTCOME MEASURE: Pain scores in the immediate postoperative period for 2 hours following surgery; this outcome measure was decided prior to data collection. RESULTS: The pain score and other outcome measures were all blinded. Measurements are all evident from the nature of the results. CONCLUSIONS: There was no clinically significant difference observed in the analgesic effect of either drug on the two groups studied. 相似文献
5.
Whereas abnormalities of the morphological tricuspid valve are common in the setting of discordant atrioventricular connections, there are only a few postmortem reports of abnormalities of the mitral valve in this condition. This report describes two patients with discordant atrioventricular connections, in whom important abnormalities of the mitral valve were found during life by cross sectional echocardiography. 相似文献
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Altered regulation of lipid biosynthesis in a mutant of Arabidopsis deficient in chloroplast glycerol-3-phosphate acyltransferase activity 总被引:13,自引:0,他引:13
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Kunst L Browse J Somerville C 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(12):4143-4147
The leaf membrane lipids of many plant species, including Arabidopsis thaliana (L.) Heynh., are synthesized by two complementary pathways that are associated with the chloroplast and the endoplasmic reticulum. By screening directly for alterations in lipid acyl-group composition, we have identified several mutants of Arabidopsis that lack the plastid pathway because of a deficiency in activity of the first enzyme in the plastid pathway of glycerolipid synthesis, acyl-ACP:sn-glycerol-3-phosphate acyltransferase (EC 2.3.1.15) (where ACP is acyl carrier protein). The lesion results in an increased synthesis of lipids by the cytoplasmic pathway that largely compensates for the loss of the plastid pathway and provides nearly normal amounts of all the lipids required for chloroplast biogenesis. However, the fatty acid composition of the leaf membrane lipids of the mutants is altered because the acyltransferases associated with the two pathways normally exhibit different substrate specificities. The remarkable flexibility of the system provides an insight into the nature of the regulatory mechanisms that allocate lipids for membrane biogenesis. 相似文献
8.
Holly James Westervelt Jessica Somerville Ruffolo Geoffrey Tremont 《Archives of clinical neuropsychology》2005,20(6):761-769
The relationship between odor identification and cognition has not been previously well characterized. The neuroanatomy of the olfactory system and the frequent finding of olfactory dysfunction in neurodegenerative diseases suggest a likely relationship between odor identification and memory, language, and executive functioning, though previous studies have often failed to demonstrate the expected relationship. The current study examined this relationship in across a continuum of ability levels (N=100). Strongest correlations were found between odor identification and language, most aspects of memory, and a measure of general cognitive functioning. Significant but more modest correlations were seen between odor identification and attention, motor, visuospatial, and executive functions. A regression analysis revealed language as the only significant predictor of olfactory performance. These findings suggest that odor identification is most closely associated with other measures of temporo-limbic functioning. The implications of these findings, particularly in consideration of the assessment of older adults, are discussed. 相似文献
9.
Staphylococcus aureus aconitase inactivation unexpectedly inhibits post-exponential-phase growth and enhances stationary-phase survival
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Somerville GA Chaussee MS Morgan CI Fitzgerald JR Dorward DW Reitzer LJ Musser JM 《Infection and immunity》2002,70(11):6373-6382
Staphylococcus aureus preferentially catabolizes glucose, generating pyruvate, which is subsequently oxidized to acetate under aerobic growth conditions. Catabolite repression of the tricarboxylic acid (TCA) cycle results in the accumulation of acetate. TCA cycle derepression coincides with exit from the exponential growth phase, the onset of acetate catabolism, and the maximal expression of secreted virulence factors. These data suggest that carbon and energy for post-exponential-phase growth and virulence factor production are derived from the catabolism of acetate mediated by the TCA cycle. To test this hypothesis, the aconitase gene was genetically inactivated in a human isolate of S. aureus, and the effects on physiology, morphology, virulence factor production, virulence for mice, and stationary-phase survival were examined. TCA cycle inactivation prevented the post-exponential growth phase catabolism of acetate, resulting in premature entry into the stationary phase. This phenotype was accompanied by a significant reduction in the production of several virulence factors and alteration in host-pathogen interaction. Unexpectedly, aconitase inactivation enhanced stationary-phase survival relative to the wild-type strain. Aconitase is an iron-sulfur cluster-containing enzyme that is highly susceptible to oxidative inactivation. We speculate that reversible loss of the iron-sulfur cluster in wild-type organisms is a survival strategy used to circumvent oxidative stress induced during host-pathogen interactions. Taken together, these data demonstrate the importance of the TCA cycle in the life cycle of this medically important pathogen. 相似文献
10.
Gene conversion is a likely cause of mutation in PKD1 总被引:3,自引:0,他引:3
Watnick TJ; Gandolph MA; Weber H; Neumann HP; Germino GG 《Human molecular genetics》1998,7(8):1239-1243
Approximately 70% of the gene responsible for the most common form of
autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in
several highly homologous copies located more proximally on chromosome 16.
We recently have described a novel technique for mutation detection in the
duplicated region of PKD1 that circumvents the difficulties posed by these
homologs. We have used this method to identify two patients with a nearly
identical cluster of base pair substitutions in exon 23. Since pseudogenes
are known to be reservoirs for mutation via gene conversion events for a
number of other diseases, we decided to test whether these sequence
differences in PKD1 could have arisen as a result of this mechanism. Using
changes in restriction digest patterns, we were able to show that these
sequence substitutions are also present in N23HA, a rodent-human somatic
cell hybrid that contains only the PKD1 homologs. Moreover, these changes
were also detected in total DNA from several affected and unaffected
individuals that did not harbor this mutation in their PKD1 gene copy. This
is the first example of gene conversion in PKD1 , and our findings
highlight the importance of using gene-specific reagents in defining PKD1
mutations.
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