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351.
Mouse Boo/Diva is an ovary-specific member of the Bcl-2 family identified through homology with the avian cell death antagonist NR13. We identified a human orthologue of Boo/Diva, which is highly conserved between mouse and human and related to avian NR13. Human Boo/Diva is also expressed in human liver and kidney in addition to the ovary. We found that green fluorescence protein (EGFP)-tagged Boo/Diva was not exclusively localized to mitochondria before the induction of apoptosis. However, EGFP-Boo/Diva translocated to mitochondria in the process of apoptosis induced by vincristine, a microtubule-interfering agent. Overexpression of human Boo/Diva promoted cell death in HeLa and 293 cells. The cell death antagonist Bcl-XL interacts with Boo, but is unable to protect 293 cells from Boo/Diva-induced cell death. Finally, we mapped human Boo/Diva to chromosome 15q21, a locus known to be related to human cervical cancer. Moreover, we found that genomic DNAs of three of 24 human cervical cancer samples display deletions within their Boo/Diva genes. This result suggests a role for human Boo/Diva in the pathogenesis of cervical cancer. 相似文献
352.
Chris J. Burwell Akihiro Nakamura Andrew McDougall V. John Neldner 《Journal of Insect Conservation》2012,16(5):777-789
Infestation of islands by exotic ants is widespread and increasing due to human activities throughout the world. Exotic ants, particularly the invasive African big-headed ant, Pheidole megacephala (Fabricius), are of great conservation concern for coral cays at the southern end of the Great Barrier Reef, Australia. Little is known, however, about the distribution and ecological impacts of invasive ants in this insular system. We surveyed the ants of 14 vegetated coral cays recording a total of 24 ant species, including at least nine exotics. Pheidole megacephala was by far the most abundant and widespread species, occurring on 11 of 14 islands, often in very large numbers. The inter-island distribution of P. megacephala was best explained by human activities, with frequently visited, and to a lesser degree disturbed islands, more likely to be infested. On large islands (≥?10?ha) P. megacephala exhibited distinct habitat preferences, occurring in significantly lower abundances within heavily-shaded Pisonia grandis forest in the centre of islands, compared to more open, fringing woodland or shrubland. On smaller islands (<10?ha) with less extensive Pisonia stands, P. megacephala penetrated throughout the forest where its abundance was similar to that in open woodland. Despite considerable differences in biotic (floristic composition) and abiotic factors (e.g. island size) as well as the spatial configuration among islands, the severity of infestation by P. megacephala best explained variation in species richness, abundance and assemblage composition of other ants. We suggest a number of strategies to manage P. megacephala infestations on these islands. 相似文献
353.
Developing an understanding of the impact of climate on Australia's alpine flora is critical in anticipating the impacts of climate change. The dendroclimatological analysis of the Australian mainland's only alpine conifer, Podocarpus lawrencei Hook.f., may have particular significance in this regard. Unfortunately, eccentric tree-ring widths and frequent ring wedging have previously prevented dendroclimatic investigation of the species using core samples. In this study, we overcome this limitation by using full stem cross-sections collected from individuals killed during wildfire in 2003. Despite this advantage, ring wedging and poor circuit uniformity meant that crossdating was successful for portions or complete sections of only 56% of samples. Nevertheless, we constructed a crossdated chronology spanning 114-years (1888–2001) – the first for P. lawrencei. Climatological analysis revealed significant positive correlations with air temperature during spring of the growing season and significant negative correlations with monthly and seasonal snow variables as well as spring precipitation. Further analyses using 50-year moving windows reveal that responses to minimum air temperature and precipitation are unstable and periodically non-significant. Nevertheless, whilst correlation with mean maximum temperature during October and November (spring) of the growing season as well as the seasonal integration of snow cover exhibits variability throughout the analysis period, this variability appears to be independent of trends in both mean temperature and snow cover. We conclude, given the species longevity, its sensitivity to climate as well as the availability of sample material throughout the Australian Alps, that P. lawrencei holds a hitherto unrealised potential for climate reconstruction in south-east Australia. Further dendrochronological investigation of the species is currently underway throughout the Australian Alps to exploit this potential. 相似文献
354.
CA Campbell AR Horvath 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2012,33(4):149-160
Timely release and communication of critical test results may have significant impact on medical decisions and subsequent patient outcomes. Laboratories therefore have an important responsibility and contribution to patient safety. Certification, accreditation and regulatory bodies also require that laboratories follow procedures to ensure patient safety, but there is limited guidance on best practices. In Australasia, no specific requirements exist in this area and critical result reporting practices have been demonstrated to be heterogeneous worldwide.Recognising the need for agreed standards and critical limits, the AACB started a quality initiative to harmonise critical result management throughout Australasia. The first step toward harmonisation is to understand current laboratory practices. Fifty eight Australasian laboratories responded to a survey and 36 laboratories shared their critical limits. Findings from this survey are compared to international practices reviewed in various surveys conducted elsewhere. For the successful operation of a critical result management system, critical tests and critical limits must be defined in collaboration with clinicians. Reporting procedures must include how critical results are identified; who can report and who can receive critical results; what is an acceptable timeframe within which results must be delivered or, if reporting fails, what escalation procedures should follow; what communication channels or systems should be used; what should be recorded and how; and how critical result procedures should be maintained and evaluated to assess impact on outcomes.In this paper we review the literature of current standards and recommendations for critical result management. Key elements of critical result reporting are discussed in view of the findings of various national surveys on existing laboratory practices, including data from our own survey in Australasia. Best practice recommendations are made that laboratories are expected to follow in order to provide high quality and safe service to patients. 相似文献
355.
356.
ISABELLE LEFÈVRE KATARINA VOGEL‐MIKUŠ LUKA JEROMEL PRIMOŽ VAVPETIČ SÉBASTIEN PLANCHON IZTOK ARČON JOHANNES T VAN ELTEREN GILLES LEPOINT SYLVIE GOBERT JENNY RENAUT PRIMOŽ PELICON STANLEY LUTTS 《Plant, cell & environment》2014,37(6):1299-1320
Cadmium and zinc share many similar physiochemical properties, but their compartmentation, complexation and impact on other mineral element distribution in plant tissues may drastically differ. In this study, we address the impact of 10 μm Cd or 50 μm Zn treatments on ion distribution in leaves of a metallicolous population of the non‐hyperaccumulating species Zygophyllum fabago at tissue and cell level, and the consequences on the plant response through a combined physiological, proteomic and metabolite approach. Micro‐proton‐induced X‐ray emission and laser ablation inductively coupled mass spectrometry analyses indicated hot spots of Cd concentrations in the vicinity of vascular bundles in response to Cd treatment, essentially bound to S‐containing compounds as revealed by extended X‐ray absorption fine structure and non‐protein thiol compounds analyses. A preferential accumulation of Zn occurred in vascular bundle and spongy mesophyll in response to Zn treatment, and was mainly bound to O/N‐ligands. Leaf proteomics and physiological status evidenced a protection of photosynthetically active tissues and the maintenance of cell turgor through specific distribution and complexation of toxic ions, reallocation of some essential elements, synthesis of proteins involved in photosynthetic apparatus or C‐metabolism, and metabolite synthesis with some specificities regarding the considered heavy metal treatment. 相似文献
357.
ABSTRACT Islam is beginning to have a significant presence in the predominantly Christian nation of Solomon Islands. A few well-educated Islanders were drawn to Islam's elegant monotheism and promise of unity in the 1980s and early 1990s, but numbers have grown significantly in the years following a violent civil conflict (1998–2003). Many of these new Muslim converts, especially those from the island of Malaita, seem preoccupied with the problem of sin and blame Christianity for destroying customary rules, especially those enforcing gender segregation. Echoing long-standing Malaitan critiques of Christian freedom, they say that Christians rely too heavily on God's grace and their own ability to resist temptation. Unlike Christianity and similar to the traditional religion of the islands, Islam provides clear moral rules for living. Seeking an escape from a cycle of sin and redemption, these ex-evangelical Christians now see in Islam the possibility of becoming sinless. 相似文献
358.
Granular cell tumours (GCT) of the soft tissues are rare benign tumours but some time may be difficult to distinguish from malignant neoplasms. It is important that clinicians are aware of their existence. We present a new case of GCT of the soft tissues followed by a brief review of literature. 相似文献
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