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Predation by introduced mammals is decimating New Zealand's indigenous fauna. Understanding factors that influence this process allows resources for predator control to be applied with maximum effect. This study examines how predation of a secondary prey species (a relatively common but declining native plover, the banded dotterel Charadrius bicinctus ) varied with reductions in abundance of a major prey source (rabbits), kill-trapping of predators, nest density and habitat complexity. Banded dotterels mostly nest in open braided riverbeds alongside a number of endemic threatened species. We measured the fate of 753 dotterel clutches exposed to predation by cats, ferrets and hedgehogs. We found key times and places of high predation risk. Immediately after widespread reduction in rabbit populations by rabbit haemorrhagic disease (RHD), clutch predation rates were almost as high (mean, 50%) as those recorded during past rabbit poisoning programmes (mean, 57%). Both rates were significantly higher than the mean predation rate of 22% without rabbit control, suggesting a shift in predator diet immediately after rabbit population declines. Unlike after rabbit poisoning, clutch predation rate remained high in the years after RHD. Other patterns observed included higher clutch predation rate where nest density was lower, suggesting that predation can potentially cause local extinction. Clutch predation was also higher along riverbed margins where vegetation was dense. There was equivocal evidence for an effect of predator kill-trapping on clutch predation rate. Management strategies that could potentially reduce clutch predation risks include focusing predator mitigation measures during periods of rabbit decline, maintaining them for more than one breeding season if the rabbit declines are widespread (e.g. RHD epidemics), and applying greater effort at sites with relatively low nest density and along riverbed margins where predator use is more frequent. 相似文献
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《Microbes and infection / Institut Pasteur》2015,17(2):109-117
Ebola virus infection can cause Ebola virus disease (EVD). Patients usually show severe symptoms, and the fatality rate can reach up to 90%. No licensed medicine is available. In this review, development of therapeutics for treatment of Ebola virus infection and EVD will be discussed. 相似文献
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《Saudi Journal of Biological Sciences》2016,23(4):462-466
The present study is to determine the prevalence and implication of coeliac disease (CD) among adult Saudis and compared to those with diagnosed irritable bowel syndrome. This prospective study was conducted among 980 adults. Out of that, 482 subjects (staff and students of Riyadh Health Science College) were designated as control cohorts for undetected coeliac disease. Furthermore, another contingent of 498 subjects diagnosed with irritable bowel syndrome (IBS) at Prince Salman Hospital and Al-Iman General Hospital also constituted a segment of the overall initial 1020 subjects. Both cases and control were tested for serological markers of coeliac disease (tissues transglutaminase (tTGAs) and endomysial autoantibody (EMAs) and were confirmed by histopathology test. All the positive for cases of coeliac disease were screened for iron deficiency anaemia, Vitamin D deficiency, and osteoporosis and weight assessment. The percentage of coeliac disease in control subjects and patients diagnosed with irritable bowel syndrome (IBS) were found to be 1.9% and 9.6% respectively, about 38% of the total coeliac disease patients are among females of middle age (20–39-years) and 16% of the males in the same age range. Whereas, 20% and 25% of all coeliac disease cases with ages of 40–59 were remarked as females and males respectively. The identical nature and overlap of symptoms of the two conditions could possibly result in misdiagnosis of coeliac diseases or over-diagnosis of irritable bowel syndrome. The findings of the study might also give considerable implications of the disease in the nutritional level which is noticeable. 相似文献
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Normal and limited vision gait was investigated in individuals with Parkinson disease (PD), healthy older and healthy young individuals. Participants walked a GAITRite mat with normal vision or vision of lower limbs occluded. Results indicate individuals with PD walked more slowly, with shorter and wider steps, and spent more time in double support with limited vision as compared to full vision. Healthy young and old individuals took shorter steps but were otherwise unchanged between conditions. 相似文献
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A One Year Audit of Fine Needle Aspiration Cytology For the Pre-Operative Diagnosis of Breast Disease 总被引:1,自引:0,他引:1
A. HITCHCOCK C. M. HUNT A. LOCKER J. KOSLOWSKI S. STRUDWICK C. W. ELSTON R. W. BLAMEY I. O. ELLIS 《Cytopathology》1991,2(4):167-176
In 1988, 985 patients presenting with breast disease, most with a palpable abnormality, were investigated by the triple approach (clinical examination, imaging and fine needle aspiration cytology [FNAC]). Using FNAC, 28% of patients were diagnosed as having carcinoma, 45% benign disease, 4% had suspicious cytology and 3% equivocal cytology. The remaining 20% had inadequate aspirates. Two false positive diagnoses of carcinoma were made (a false positive rate of 0.7%); one was a case of high grade non-Hodgkin's lymphoma and the other a papillary lesion with epithelial atypia. The false negative rate was 6.4%. Of these 49 patients, six had carcinoma-in-situ and 19 had low grade tumours. The absolute and complete sensitivities for the diagnosis of carcinoma in this series were 84.7% and 91.9% respectively and the absolute and complete specificities 99.7% and 98.3%, respectively. These figures compare favourably with those from other centres and confirm the efficacy of FNAC as part of the triple approach to the diagnosis of breast disease. The use of FNAC has resulted in a reduction in the number of Trucut and frozen section biopsies performed. Eighty three per cent of the patients with benign disease diagnosed by the triple approach have avoided excision biopsy, none of whom have subsequently been found to have carcinoma. Eighty patients with advanced breast carcinoma were spared operative intervention. 相似文献
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T. H. Lanthorn 《Amino acids》1994,6(3):247-260
Summary D-Cycloserine can enhance activation of the NMDA receptor complex and could enhance the induction of long-term potentiation (LTP). In animals and humans, D-cycloserine can enhance performance in learning and memory tasks. This enhancing effect can disappear during repeated administration. The enhancing effects are also lost when higher doses are used, and replaced by behavioral and biochemical effects like those produced by NMDA antagonists. It has been reported that NMDA agonists, applied before or after tetanic stimulation, can block the induction of LTP. This may be the result of feedback inhibition of second messenger pathways stimulated by receptor activation. This may explain the antagonist-like effects of glycine partial agonists like D-cycloserine. In clinical trials of D-cycloserine in age-associated memory impairment (AAMI) and Alzheimer's disease, chronic treatment provided few positive effects on learning and memory. This may be due to inhibition of second messenger pathways following chronic stimulation of the receptor complex. 相似文献