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1.
Munir Virani 《Ostrich》2013,84(1-2):139-142
Virani, M. 2000. Home range and movement patterns of Sokoke Scops Owl Otus ireneae. Ostrich 71 (1 & 2): 139–142.

A radio-telemetric study of the endangered Sokoke Scops Owl Otus ireneae was conducted between July and December 1993. The aims were to determine the species' home range and movement patterns with respect to time and moon phases. Information gathered would then be used to formulate a rational conservation plan to ensure their survival. Six adult owls (from three adjacent pairs) were monitored during the study period. Pairs held exclusive home ranges with little (2.6%) or no overlap with their neighbours. Mean home range size (MCP) of individual owls was 8.8 ha while mean home range size of each pair was 11.0 ha. Peak owl activity took place immediately after dusk and prior to dawn. Periods of lulls occurred between 23h00 and 03h00. Movement per unit time was negatively correlated with distance from roost. The owls tended to forage further from their roosts on nights with decreased illumination from the moon. Maximum owl distances from roosts were attained between 00h00 and 02h00.  相似文献   
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We report the inhibition of the causative agents of dental caries, Streptococcus mutans and other oral streptococci, by the antimicrobially active ingredients of the hop plant (Humulus lupulus L.). The hop constituents studied were purified beta acid, xanthohumol, isoalpha acid and tetra iso-alpha acid. Cruder hop extracts were also investigated. The antimicrobial activity of these hop constituents was tested against four strainsof Streptococcus mutans as well as one strain each ofStreptococcus sanguis andStreptococcus salivarius and compared to antimicrobial essential oils used in mouthwashes in two independent assay systems. We found that all tested hop constituents inhibited the Streptococci. The minimum inhibitory concentration at pH 7.5 ranged from 2 to 50 μg/ml depending on the microorganism and hop phytochemical tested. Contrary to a previous report, there was no activity enhancement by ascorbic acid over and above the enhancement due to pH lowering. Thére was no resistance development to beta acid after 10 passages in a subinhibitory concentration of this acid. Antimicrobial activity of hop constituents was found to be greater than other plant products such as thymol, nerol, cinnamon oil, oil of clove, menthol and eucalyptol. The possibilities of using hop constituents in mouthwashes are discussed.  相似文献   
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Terminal deoxynucleotidyl transferase (TdT) deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) is the method of using the TdT enzyme to covalently attach a tagged form of dUTP to 3’ ends of double- and single-stranded DNA breaks in cells. It is a reliable and useful method to detect DNA damage and cell death in situ. This video describes dissection, tissue processing, sectioning, and fluorescence-based TUNEL labeling of mouse skeletal muscle. It also describes a method of semi-automated TUNEL signal quantitation. Inherent normal tissue features and tissue processing conditions affect the ability of the TdT enzyme to efficiently label DNA. Tissue processing may also add undesirable autofluorescence that will interfere with TUNEL signal detection. Therefore, it is important to empirically determine tissue processing and TUNEL labeling methods that will yield the optimal signal-to-noise ratio for subsequent quantitation. The fluorescence-based assay described here provides a way to exclude autofluorescent signal by digital channel subtraction. The TUNEL assay, used with appropriate tissue processing techniques and controls, is a relatively fast, reproducible, quantitative method for detecting apoptosis in tissue. It can be used to confirm DNA damage and apoptosis as pathological mechanisms, to identify affected cell types, and to assess the efficacy of therapeutic treatments in vivo.  相似文献   
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The White‐headed Vulture Trigonoceps occipitalis (WhV) is uncommon and largely restricted to protected areas across its range in sub‐Saharan Africa. We used the World Database on Protected Areas to identify protected areas (PAs) likely to contain White‐headed Vultures. Vulture occurrence on road transects in Southern, East, and West Africa was adjusted to nests per km2 using data from areas with known numbers of nests and corresponding road transect data. Nest density was used to calculate the number of WhV nests within identified PAs and from there extrapolated to estimate the global population. Across a fragmented range, 400 PAs are estimated to contain 1893 WhV nests. Eastern Africa is estimated to contain 721 nests, Central Africa 548 nests, Southern Africa 468 nests, and West Africa 156 nests. Including immature and nonbreeding birds, and accounting for data deficient PAs, the estimated global population is 5475 ‐ 5493 birds. The identified distribution highlights are alarming: over 78% (n = 313) of identified PAs contain fewer than five nests. A further 17% (n = 68) of PAs contain 5 ‐ 20 nests and 4% (n = 14) of identified PAs are estimated to contain >20 nests. Just 1% (n = 5) of PAs are estimated to contain >40 nests; none is located in West Africa. Whilst ranging behavior of WhVs is currently unknown, 35% of PAs large enough to hold >20 nests are isolated by more than 100 km from other PAs. Spatially discrete and unpredictable mortality events such as poisoning pose major threats to small localized vulture populations and will accelerate ongoing local extinctions. Apart from reducing the threat of poisoning events, conservation actions promoting linkages between protected areas should be pursued. Identifying potential areas for assisted re‐establishment via translocation offers the potential to expand the range of this species and alleviate risk.  相似文献   
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BackgroundDespite technical advances in coronary artery bypass grafting (CABG), early postoperative myocardial ischaemia still remains a challenging problem. The aim of this study was to determine the incidence, clinical features, angiographic characteristics, and management of early graft failure in the present CABG era. MethodsBetween January 1997 and December 2002, 1731 patients underwent CABG at our institution. Coronary angiography was performed in patients with clinical evidence of early postoperative ischaemia (≤3 months). Thirty of these patients with graft failure constituted the population of this study. ResultsOff-pump and on-pump CABG were almost evenly performed in these patients [n=16 (53%) and n=14 (47%) respectively]. Acute myocardial infarction and unstable angina were the leading indications for coronary angiography in the majority of patients [n=28 (93%)]. The most common cause of graft failure was occlusion / thrombosis [n=20 (67%)]. Percutaneous coronary intervention (PCI) was offered to the majority of patients [n=22 (73%)]. Of these patients, 14 underwent PCI to native coronary arteries, whereas eight underwent PCI to the culprit vessel. Three patients underwent reoperation, and five received medical management. Four patients (13%) died in hospital (two after redo CABG, one after unsuccessful PCI, and one patient managed medically). Two patients (7%) had nonfatal major complications (one non-ST-elevation myocardial infarction and one stroke). ConclusionEarly graft failure generally presents as acute coronary syndrome. Graft occlusion/ thrombosis is the leading cause of ischaemia. Patients with graft failure can undergo PCI with a relatively low risk, but the need for redo CABG in associated with a high mortality. (Neth Heart J 2009;17:13-7.)  相似文献   
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The receptor tyrosine kinase c-Met and its ligand, hepatocyte growth factor/scatter factor (HGF/SF), modulate signaling cascades implicated in cellular proliferation, survival, migration, invasion, and angiogenesis. Therefore, dysregulation of HGF/c-Met signaling can compromise the cellular capacity to moderate these activities and can lead to tumorigenesis, metastasis, and therapeutic resistance in various human malignancies. To facilitate studies investigating HGF/c-Met receptor coupling or c-Met signaling events in real time and in living cells and animals, here we describe a genetically engineered reporter where bioluminescence can be used as a surrogate for c-Met tyrosine kinase activity. c-Met kinase activity in cultured cells and tumor xenografts was monitored quantitatively and dynamically in response to the activation or inhibition of the HGF/c-Met signaling pathway. Treatment of tumor-bearing animals with a c-Met inhibitor and the HGF neutralizing antibody stimulated the reporter’s bioluminescence activity in a dose-dependent manner and led to a regression of U-87 MG tumor xenografts. Results obtained from these studies provide unique insights into the pharmacokinetics and pharmacodynamics of agents that modulate c-Met activity and validate c-Met as a target for human glioblastoma therapy.  相似文献   
10.
The usage of invasive tagging methods to assess lizard populations has often been criticised, due to the potential negative effects of marking, which possibly cause increased mortality or altered behaviour. The development of safe, less invasive techniques is essential for improved ecological study and conservation of lizard populations. In this study, we describe a photographic capture-recapture (CR) technique for estimating Draco dussumieri (Agamidae) populations. We used photographs of the ventral surface of the patagium to identify individuals. To establish that the naturally occurring blotches remained constant through time, we compared capture and recapture photographs of 45 pen-marked individuals after a 30 day interval. No changes in blotches were observed and individual lizards could be identified with 100% accuracy. The population density of D. dussumieri in a two hectare areca-nut plantation was estimated using the CR technique with ten sampling occasions over a ten day period. The resulting recapture histories for 24 individuals were analysed using population models in the program CAPTURE. All models indicated that nearly all individuals were captured. The estimated probability for capturing D. dussumieri on at least one occasion was 0.92 and the estimated population density was 13±1.65 lizards/ha. Our results demonstrate the potential for applying CR to population studies in gliding lizards (Draco spp.) and other species with distinctive markings.  相似文献   
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