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71.
Abstract Theory predicts that compared with active searchers, ambush foragers should have lower rates of energy intake, slower growth, and higher survival rates. We tested these predictions with data on two species of sympatric, saurophagous, small‐bodied, viviparous elapid snakes: the broad‐headed snake, Hoplocephalus bungaroides, and the small‐eyed snake, Rhinoplocephalus nigrescens. Demographic parameters and growth curves for both species were estimated from a long‐term (9 years) mark‐recapture study in Morton National Park, south‐eastern Australia. The ambush predator (H. bungaroides) displayed slower juvenile growth and later maturation (5 years for males, 6 years for females) than did the active forager (R. nigrescens, 3 years). Litter sizes were similar in both species, but reproductive frequency was higher in R. nigrescens (90–100%) than in H. bungaroides (50%). Juvenile survival was lower in the active searcher (31%) than in the ambush forager (55%), but adult survivorship was similar (74% vs 82%). Our results support the hypothesis that ambush foragers display ‘slow’ life history traits, but additional phylogenetically independent comparisons are needed to evaluate the generality of this pattern. 相似文献
72.
With the use of a staining method by which cells in the urine can be differentiated, the effect of oral frusemide, lactose, and urea on the rate of excretion of these cells was investigated in five healthy persons.It is shown that frusemide greatly increases the urinary excretion of red cells, white cells, and renal tubular cells. Similar though not so marked changes were produced by both lactose and urea. Possible reasons for the increased excretion of cells are discussed. One is that it may be the result of an increase in the rate of urinary flow. 相似文献
73.
P E Mullis S Liechti-Gallati L Di Silvio C G Brook A F Paes-Alves 《Hormone research》1991,36(1-2):4-8
A recent longitudinal study in children with cystic fibrosis (CF) challenged the common idea that CF is causing short stature. The data, however, showed clearly that short stature cannot be explained by CF alone after the first year of life. We report on a girl suffering from CF and short stature in whom DNA analysis using polymerase chain reaction and Southern blot techniques of the human growth hormone (hGH) gene cluster revealed a 6.7-kb gene deletion encompassing the hGH-1 gene. Anti-hGH antibodies of polyclonal origin developed, leading to a growth arrest after only 2 months of hGH replacement. In addition, a family study was performed, and the haplotypes of the CF gene and hGH gene cluster were analyzed. 相似文献
74.
75.
76.
P Brook 《BMJ (Clinical research ed.)》1980,281(6243):787-788
All consultants in general psychiatry appointed between 1 October 1975 and 30 September 1978 were sent a questionnaire asking about their training experience in various aspects of psychiatric practice. The results showed that the standard of training in several important areas of psychiatry were generally poor, although psychiatrists who had trained at the Maudsley Hospital or in teaching hospitals had better training than those who had worked in psychiatric hospitals. As compared with the last survey made three years ago there had been some improvement, but it had been least pronounced in psychiatric hospitals. The effects of approval visits made by both the Royal College of Psychiatrists and the Joint Committee of Higher Psychiatric Training would seem to be achieving results, but more attention needs to be paid to the standard of training in psychiatric hospitals and units. 相似文献
77.
Alexis Brook 《BMJ (Clinical research ed.)》1988,297(6646):487-488
78.
Localization of a human Na+,K+-ATPase alpha subunit gene to chromosome 19q12----q13.2 and linkage to the myotonic dystrophy locus 总被引:3,自引:0,他引:3
H G Harley J D Brook C L Jackson T Glaser K V Walsh M Sarfarazi R Kent M Lager M Koch P S Harper 《Genomics》1988,3(4):380-384
The gene coding for a Na+,K+-ATPase alpha subunit (ATP1A3) has been localized to the q12----q13.2 region of human chromosome 19, potentially close to the myotonic dystrophy (DM) gene. In view of previous studies implicating a Na+,K+-ATPase in the pathology of DM, we have examined the possibility that ATP1A3 is a candidate for the DM locus. Although linked, several clear instances of recombination between ATP1A3 and DM rule out the possibility that mutations in ATP1A3 cause the disease. Examination of multiply informative pedigrees indicates the gene order DM-APOC2-ATP1A3. 相似文献
79.
EO Ogueji CD Nwani SC Iheanacho CE Mbah CO Okeke A Yaji 《African Journal of Aquatic Science》2018,43(3):293-303
Indiscriminate discharge of pharmaceutical waste into the aquatic ecosystem may pose serious health challenges to aquatic biota. The effect of acute exposure to ibuprofen was evaluated using changes in behaviour and haematological parameters under static bio-assay method in Clarias gariepinus. Test specimens were exposed to acute concentrations of ibuprofen (0.28, 0.33, 0.38, 0.43 and 0.48 mg l?1) for 24, 48, 72 and 96 h durations respectively. Behavioural and phenotypic changes were observed in surviving fish. There were significant (p < 0.05) concentration and duration-dependent increases in erythrocyte (RBC), haemoglobin (Hb), pack cell volume (PCV) and leukocytes (WBC) in treated fish compared to the control. Insignificant decreases (p > 0.05) in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were observed in treated fish compared to the control. Ibuprofen elicited dose and duration- dependent decrease in neutrophil counts with the decreases being significant (p < 0.05) in the higher doses of 0.43 and 0.48 mg l?1. Ibuprofen did not elicit any significant changes in monocytes, basophils and eosinophils. Changes observed in this study showed that ibuprofen negatively affected the health of the fish and we recommend that discharge of ibuprofen into the aquatic environment should be monitored and controlled. 相似文献
80.
Isolation and identification of Burkholderia pseudomallei from soil using selective culture techniques and the polymerase chain reaction 总被引:3,自引:0,他引:3
An environmental soil survey to detect Burkholderia pseudomallei was performed during the dry and wet seasons in Darwin, Northern Territory, Australia. Soil was sampled at regular intervals during a 15-month period at different depths from areas which were representative of the local, soil environment. Selective culture techniques using Ashdown's and Galimand and Dodin's methods and the polymerase chain reaction (PCR) using specific 16S rRNA primers were used to detect and identify the organism and determine its distribution within the soil stratum over the change in seasons. Results showed that Ashdown's method gave higher isolation rates in the dry season, and Galimand and Dodin's method gave higher isolation rates during the wet season. PCR of the soil enrichment proved to be a more sensitive method than culture and was also a useful confirmatory test in determining the identification of isolates where biochemical tests gave inconsistent results. The PCR primers were specific and able to detect 101 cfu g-1 soil and 104 cfu g-1 of soil using Ashdown's enrichment broth and Galimand and Dodin's broth, respectively. Overall the isolation of B. pseudomallei was greatest during the dry season and at the higher and lower soil depths, which is contradictory to epidemiological evidence that melioidosis occurs primarily during the wet season among patients exposed to contaminated surface soil and water. 相似文献