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31.
A controlled trial was conducted to determine whether counselling by a specialist nurse prevented the psychiatric morbidity associated with mastectomy and breast cancer. Seventy-five patients were counselled by the nurse and monitored during follow-up, while 77 patients received only the care normally given by the surgical unit. Counselling failed to prevent morbidity, but the nurse''s regular monitoring of the women''s progress led her to recognise and refer 76% of those who needed psychiatric help. Only 15% of the control group whose condition warranted help were recognised and referred. Consequently, 12 to 18 months after mastectomy there was much less psychiatric morbidity in the counselled group (12%) than in the control group (39%). These findings highlight the high degree of psychiatric morbidity in patients who have undergone mastectomy and indicate the need to find ways of reducing this morbidity. 相似文献
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Juvenile turbot,Scophthalmus maximus (L.), were exposed to 0.58 μg 1−1 Aroclor 1254 in seawater, to sediments containing 100, 60 and 1 ppm or fed with cockle containing 20 ppm PCB (polychlorinated
biphenyls). Concentration factors for liver and muscle were 104 and 103, respectively, for uptake of PCB from seawater. Contamination of muscle was similar to that of sediments containing 1 and
60 ppm PCB to which turbot were exposed, but less than the 20 ppm in their experimental diet. Contamination of flatfish in
the North Sea area is compared with the levels of PCB in the flounder,Platichthys flesus (L.), in the River Thames and predictable values for uptake of PCB from different pathways discussed. 相似文献
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J M Hagberg E F Coyle J E Carroll J M Miller W H Martin M H Brooke 《Journal of applied physiology (Bethesda, Md. : 1985)》1982,52(4):991-994
This study was undertaken to determine if patients who lack muscle phosphorylase (i.e., McArdle's disease), and therefore the ability to produce lactic acid during exercise, demonstrate a normal hyperventilatory response during progressive incremental exercise. As expected these patients did not increase their blood lactate above resting levels, whereas the blood lactate levels of normal subjects increased 8- to 10-fold during maximal exercise. The venous pH of the normal subjects decreased markedly during exercise that resulted in hyperventilation. The patients demonstrated a distinct increase in ventilation with respect to O2 consumption similar to that seen in normal individuals during submaximal exercise. However their hyperventilation resulted in an increase in pH because there was no underlying metabolic acidosis. End-tidal partial pressures of O2 and CO2 also reflected a distinct hyperventilation in both groups at approximately 70-85% maximal O2 consumption. These data show that hyperventilation occurs during intense exercise, even when there is no increase in plasma [H+]. Since arterial CO2 levels were decreasing and O2 levels were increasing during the hyperventilation, it is possible that nonhumoral stimuli originating in the active muscles or in the brain elicit the hyperventilation observed during intense exercise. 相似文献
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DNA-negative temperature-sensitive mutants of herpes simplex virus type 1: patterns of viral DNA synthesis after temperature shift-up. 总被引:5,自引:5,他引:0 下载免费PDF全文
Temperature-sensitive mutants of herpes simplex virus type 1 belonging to four DNA- complementation groups exhibited two distinct patterns of viral DNA synthesis after shift-up to the nonpermissive temperature. In cultures infected with mutants belonging to complementation groups A, C, and D, little or no viral DNA was synthesized after shift-up. In cultures infected with a mutant in complementation group B, nearly normal amounts of viral DNA were synthesized after shift-up. 相似文献
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Justin Mancini Brooke Weckselblatt Yoonjie K. Chung Julia C. Durante Steven Andelman Jessica Glaubman Justin D. Dorff Samhita Bhargava Rebeccah S. Lijek Katherine P. Unger Iruka N. Okeke 《Journal of bacteriology》2011,193(18):4813-4820
Heat-resistant agglutinin 1 (Hra1) is an accessory colonization factor of enteroaggregative Escherichia coli (EAEC) strain 042. Tia, a close homolog of Hra1, is an invasin and adhesin that has been described in enterotoxigenic E. coli. We devised a PCR-restriction fragment length polymorphism screen for the associated genes and found that they occur among 55 (36.7%) of the enteroaggregative E. coli isolates screened, as well as lower proportions of enterotoxigenic, enteropathogenic, enterohemorrhagic, and commensal E. coli isolates. Overall, 25%, 8%, and 3% of 150 EAEC strains harbored hra1 alone, tia alone, or both genes, respectively. One EAEC isolate, 60A, produced an amplicon with a unique restriction profile, distinct from those of hra1 and tia. We cloned and sequenced the full-length agglutinin gene from strain 60A and have designated it hra2. The hra2 gene was not detected in any of 257 diarrheagenic E. coli isolates in our collection but is present in the genome of Salmonella enterica serovar Heidelberg strain SL476. The cloned hra2 gene from strain 60A, which encodes a predicted amino acid sequence that is 64% identical to that of Hra1 and 68% identical to that of Tia, was sufficient to confer adherence on E. coli K-12. We constructed an hra2 deletion mutant of EAEC strain 60A. The mutant was deficient in adherence but not autoaggregation or invasion, pointing to a functional distinction from the autoagglutinin Hra1 and the Tia invasin. Hra1, Tia, and the novel accessory adhesin Hra2 are members of a family of integral outer membrane proteins that confer different colonization-associated phenotypes. 相似文献
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Eucalyptin and 8-desmethyleucalyptin have been isolated from the leaf wax coatings of several species of Eucalyptus, from Syncarpia glomulifera, Lophostemon confertus and an Angophora hybrid indicating that C-methylated flavones may be fairly distinctive of the family Myrtaceae. Ursolic acid has been isolated from the leaf waxes of E. youmanii, S. glomulifera, Leptospermum petersonii and Melaleuca quinquenervia, friedelin from Lophostemon confertus and 4,6-dimethoxy-2-hydroxyacetophenone from E. michaeliana. 相似文献
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