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951.
Background
All polypeptide backbones have the potential to form amyloid fibrils, which are associated with a number of degenerative disorders. However, the likelihood that amyloidosis would actually occur under physiological conditions depends largely on the amino acid composition of a protein. We explore using a naive Bayesian classifier and a weighted decision tree for predicting the amyloidogenicity of immunoglobulin sequences. 相似文献952.
953.
Hermes copper butterfly (Lycaena [Hermelycaena] hermes) is a rare species inhabiting the coastal sage scrub adjacent to San Diego, CA USA. Conservation groups and wildlife agencies
recognize this species is threatened by habitat loss due to urbanization and recent wildfires extirpating local populations.
To assess the status of the Hermes copper, we summarize the literature concerning taxonomy, distribution, and ecology, as
well as present original distributional and ecological data. Adults were sampled by presence/absence surveys, Pollard Walks,
and mark-release-recapture. The current distribution is reduced from historic ranges, specifically in extreme southern and
northern San Diego County. Recent wildfires in 2003 and 2007 led to the extirpation of many populations, with only one post-fire
recolonization documented. Adult emergence dates ranged from mid-May to early June, while densities varied from five to nine-fold
among years based on peak abundance and mark-release-recapture estimates, respectively. We observed significantly more males;
most were territorial and exhibit a relatively sedentary behavior. The median dispersal range was 25.8 and 11.3 m, and the
median minimum distance traveled was 34.4 and 17.6 m at Rancho Jamul Ecological Reserve and Hollenbeck Canyon Wildlife Area,
respectively. The longest recorded movement by an individual was 1,132.0 m. Post-fire habitat recovery and the ability to
move across the landscape are essential for the Hermes copper to persist in an increasingly dynamic and fragmented coastal
sage scrub habitat. Therefore, we need to develop a better understanding of habitat requirements and connectivity of populations
for the long-term management and conservation of this species. 相似文献
954.
TNF inhibitors are currently considered both effective and cost-effective in patients with active rheumatoid arthritis (RA), particularly in patients who have not responded fully to methotrexate. There is substantial doubt about the cost-effectiveness of TNF inhibitors as initial treatment for active RA. New data from the National Data Bank for Rheumatic Diseases now question the current consensus in methotrexate failures. The data suggest that in routine clinical practice TNF inhibitors provide only modest incremental benefits over best conventional therapy. If confirmed, these observational studies suggest that the economic argument underpinning the widespread use of TNF inhibitors in established RA is unsustainable. 相似文献
955.
Koichi Murata Hiroyuki Yoshitomi Shimei Tanida Masahiro Ishikawa Kohei Nishitani Hiromu Ito Takashi Nakamura 《Arthritis research & therapy》2010,12(3):R86
Introduction
MicroRNAs (miRNAs), endogenous small noncoding RNAs regulating the activities of target mRNAs and cellular processes, are present in human plasma in a stable form. In this study, we investigated whether miRNAs are also stably present in synovial fluids and whether plasma and synovial fluid miRNAs could be biomarkers of rheumatoid arthritis (RA) and osteoarthritis (OA). 相似文献956.
Background
In this paper we present a novel scene retargeting technique to reduce the visual scene while maintaining the size of the key features. The algorithm is scalable to implementation onto portable devices, and thus, has potential for augmented reality systems to provide visual support for those with tunnel vision. We therefore test the efficacy of our algorithm on shrinking the visual scene into the remaining field of view for those patients. 相似文献957.
Downy mildew (Peronospora plantaginis) caused two different types of infection in the floral parts of isabgol (Plantago ovata). Systemic infection resulted in long spikes bearing weak and sterile florets, which later turned black due to saprophytic
growth. Localised infection produced various symptoms ranging between normal flower opening and failure to bloom. Different
parts of infected flowers such as sepal, petal, filament and anther were reduced in size compared to healthy flowers. However,
gynoecium was elongated in localised infection. P. plantaginis induced gradual sterility of isabgol flowers. Androecium was affected more than the gynoecium was. Pollen number, pollen
viability and germination reduced drastically due to localised infection. On the contrary, there were no significant differences
between healthy and locally infected flowers in terms of stigma receptivity. In systemically infected spikes, bud development
was arrested leading to sterility. When localised disease severity was high, secondary systemic infection caused similar symptoms.
Microscopic observations showed presence of the pathogen in different parts of the flowers. Downy mildew adversely affected
seed yield and quality; producing seeds, which were smaller and lighter than the healthy ones and later, became black. Seed
yield was reduced by as much as 73.45 percent. Husk content per unit seed mass increased relatively as the total surface area
of infected seeds increased. 相似文献
958.
959.
960.
<Emphasis Type="Italic">Daphnia galeata</Emphasis> in the deep hypolimnion: spatial differentiation of a “typical epilimnetic” species 总被引:1,自引:1,他引:1
One of the most serious threats to tropical mangrove ecosystems caused by shrimp farming activities is the poor management
of pond waste materials. We hypothesise that mangroves can tolerate chemical residues discharged from shrimp farms and can
be used as biofilters, but the capability of mangroves to cope with solid sediments dredged from shrimp ponds is limited.
Our study in Pak Phanang, Thailand, confirmed that the excess sediments discharged from nearby shrimp ponds reduced mangrove
growth rates and increased mortality rates. A series of transformed multi-temporal satellite images was used in combination
with the field data to support this claim. In addition, a comparison between four dominant mangrove species revealed that
Avicennia marina could tolerate sedimentation rates of >6 cm year−1, while Bruguiera cylindrica tolerated sedimentation rates of 5 cm year−1 (total sediment depth = 25 cm) before dying, while Excoecaria agallocha and Lumnitzera racemosa performed intermediate. This outcome implied that in our situation A. marina and to lesser extent E. agallocha and L. racemosa could be more effective as biofilters than B. cylindrica, as they may survive the sedimentation longer in the disposal areas. Further studies on the impact of sedimentation and chemical
pollution of shrimp farm wastes on mangrove mortality and growth are required. 相似文献