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61.
Melanin granules melanophages and a fully‐melanized epidermis are common traits of odontocete and mysticete cetaceans 
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下载免费PDF全文 62.
G. Diane Shelton 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(3):278-295
Abstract: The diagnosis of neuromuscular diseases can be challenging. The first step is recognition that the disease involves the neuromuscular system (muscle, neuromuscular junction, peripheral nerve, and ventral horn cells of the spinal cord). Many neuromuscular diseases share clinical signs and cannot be distinguished based on clinical examination. Routine laboratory screening, including a CBC, biochemical profile, and urinalysis, can identify some of the most common systemic abnormalities that cause muscle weakness and myalgia, such as hypo‐ and hyperglycemia, electrolyte disorders, or thyroid abnormalities, and may suggest a specific diagnosis, such as diabetes mellitus, hypo‐ or hyperadrenocorticism, renal failure, or hypothyroidism. Increased creatine kinase activity, increased cardiac troponin I concentration, and myoglobinuria are useful in detecting skeletal and cardiac muscle damage. Identification of acetylcholine receptor antibodies is diagnostic for acquired myasthenia gravis. For primary muscle or peripheral nerve diseases, tissue biopsy is the most direct way to determine specific pathology, correctly classify the disease, and determine the course of additional laboratory testing. For example, inflammatory, necrotizing, dystrophic, metabolic, or congenital myopathies require different laboratory testing procedures for further characterization. Many neuromuscular diseases are inherited or breed‐associated, and DNA‐based tests may already be established or may be feasible to develop after the disorder has been accurately characterized. This review focuses on both routine and specialized laboratory testing necessary to reach a definitive diagnosis and determine an accurate prognosis for neuromuscular diseases. 相似文献
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Colaprete A Schultz P Heldmann J Wooden D Shirley M Ennico K Hermalyn B Marshall W Ricco A Elphic RC Goldstein D Summy D Bart GD Asphaug E Korycansky D Landis D Sollitt L 《Science (New York, N.Y.)》2010,330(6003):463-468
Several remote observations have indicated that water ice may be presented in permanently shadowed craters of the Moon. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was designed to provide direct evidence. On 9 October 2009, a spent Centaur rocket struck the persistently shadowed region within the lunar south pole crater Cabeus, ejecting debris, dust, and vapor. This material was observed by a second "shepherding" spacecraft, which carried nine instruments, including cameras, spectrometers, and a radiometer. Near-infrared absorbance attributed to water vapor and ice and ultraviolet emissions attributable to hydroxyl radicals support the presence of water in the debris. The maximum total water vapor and water ice within the instrument field of view was 155 ± 12 kilograms. Given the estimated total excavated mass of regolith that reached sunlight, and hence was observable, the concentration of water ice in the regolith at the LCROSS impact site is estimated to be 5.6 ± 2.9% by mass. In addition to water, spectral bands of a number of other volatile compounds were observed, including light hydrocarbons, sulfur-bearing species, and carbon dioxide. 相似文献
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Global change is exacerbating the need for more effective mechanisms and approaches for working towards economic, social/cultural
and environmental sustainability. It is now well recognised that science for sustainability will require integrated problem-focussed
research that is by nature trans-disciplinary. Resolutions to both global and regional scale issues must involve participation
of a diverse number of stakeholders. One region that would benefit greatly from such an integrated approach is the Northern
Territory of Australia. This area is home to some of the most pristine savanna landscapes in the world and it is also occupied
by one of the oldest living human cultures which are still in existence today. However, in recent years there has been increasing
pressure to develop this region. The Northern Territory is also facing problems associated with having a growing Aboriginal
population with deepening health and social problems. So as well as needing to facilitate adaptation in response to global
change and development for economic prosperity of the region, there is an obligation to alter management practices to reduce
social disadvantage. In light of this, it will be important that future landscapes are multifunctional and designed to ensure
the preservation of biological and cultural diversity, as well as having provision for the livelihoods of the people that
live within them. This article recommends the adoption of a landscape ecological approach for strategic development and sustainable
planning, which captures and incorporates the values and identities of the different stakeholders, as well as engaging them
in a continuous, adaptive process of planning and management, and in doing so discusses the importance of human ecological
holism as part of the conceptual framework for landscape ecology. 相似文献
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