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991.
Sanjay G. Revankar 《Current fungal infection reports》2010,4(1):46-51
Brown–black (or dematiaceous) fungi are responsible for a wide variety of infectious syndromes in both immunocompetent and
immunocompromised patients, including local infections, allergic disease, pneumonia, brain abscess, and disseminated infection.
They are distinct from the more common hyaline molds, Aspergillus and Fusarium, that cause human disease. They are often found in soil and generally distributed worldwide. In recent years, these fungi
have been increasingly recognized as important pathogens. Dematiaceous fungi may have unique pathogenic mechanisms owing to
the presence of melanin in their cell walls, which imparts the characteristic dark color to their spores and hyphae. Diagnosis
rests on careful microscopic and pathologic examination, as there are no specific laboratory tests to reliably identify these
fungi. Therapy depends upon the clinical syndrome, although disseminated infection often has high mortality. Triazoles such
as voriconazole, posaconazole, and itraconazole are the most active antifungal agents available. Further studies are needed
to better understand the pathogenesis and optimal treatment of these uncommon infections. 相似文献
992.
993.
Winfried Häuser Petra Klose Jost Langhorst Babak Moradi Mario Steinbach Marcus Schiltenwolf Angela Busch 《Arthritis research & therapy》2010,12(3):R79
Introduction
The efficacy and the optimal type and volume of aerobic exercise (AE) in fibromyalgia syndrome (FMS) are not established. We therefore assessed the efficacy of different types and volumes of AE in FMS. 相似文献994.
995.
996.
Atanu Sarkar 《EcoHealth》2010,7(1):114-126
Millions of people living in India are at risk by consuming arsenic contaminated groundwater. Several technological solutions
have failed to address the problem due to segmental approaches, resulting in human suffering for a period of three decades.
The article is based on an analysis of arsenic-related health problems from an ecosystem perspective through a primary survey
conducted in five arsenic affected villages in the state of West Bengal and review of existing research and policy documents.
Although modern agricultural practices and drinking water policies have resulted in arsenic contamination of groundwater,
current mitigation policy is essentially confined to biomedical approaches, which includes potable water supply and medical
care. The study also shows that existing disparity, difficulty in coping, inaccessibility to health service and potable water
supply and lack of participation in decision making have resulted in more suffering among the poor. On the other hand, spreading
of arsenic contamination in the ecosystem remains unabated. Foods grown in the affected area have emerged as additional sources
of exposure to humans. There is lack of evidence of any perceivable benefits due to sustainable agriculture, as present nature
of agriculture practice is essentially driven by crop yield only. Further research is needed to generate credible evidence
of alternative agriculture paradigms that may eventually reduce body burden of arsenic through reduced dependency on groundwater. 相似文献
997.
998.
Norihide Hinomoto Tomomi Higaki Junichiro Abe Masafumi Yamane Eizi Yano 《Applied Entomology and Zoology》2012,47(2):165-171
We have developed and characterized 21 microsatellite markers in the aphidophagous gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). All 21 loci tested were polymorphic: the number of alleles ranged from 2 to 17. Allelic
richness and observed heterozygosities were higher in females than in males. Several loci had no heterozygosity in males,
suggesting that the loci were located on sex chromosomes or E-chromosomes, common to cecidomyiids. The high polymorphism detected
in this study suggests the markers will be of value in analyzing genetic structure of field populations. 相似文献
999.
Jessie K. Edwards Stephen R. Cole Daniel Westreich Richard Moore Christopher Mathews Elvin Geng Joseph J. Eron Michael J. Mugavero for the CNICS Research Network 《PloS one》2014,9(7)
Missing outcome data due to loss to follow-up occurs frequently in clinical cohort studies of HIV-infected patients. Censoring patients when they become lost can produce inaccurate results if the risk of the outcome among the censored patients differs from the risk of the outcome among patients remaining under observation. We examine whether patients who are considered lost to follow up are at increased risk of mortality compared to those who remain under observation. Patients from the US Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) who newly initiated combination antiretroviral therapy between January 1, 1998 and December 31, 2009 and survived for at least one year were included in the study. Mortality information was available for all participants regardless of continued observation in the CNICS. We compare mortality between patients retained in the cohort and those lost-to-clinic, as commonly defined by a 12-month gap in care. Patients who were considered lost-to-clinic had modestly elevated mortality compared to patients who remained under observation after 5 years (risk ratio (RR): 1.2; 95% CI: 0.9, 1.5). Results were similar after redefining loss-to-clinic as 6 months (RR: 1.0; 95% CI: 0.8, 1.3) or 18 months (RR: 1.2; 95% CI: 0.8, 1.6) without a documented clinic visit. The small increase in mortality associated with becoming lost to clinic suggests that these patients were not lost to care, rather they likely transitioned to care at a facility outside the study. The modestly higher mortality among patients who were lost-to-clinic implies that when we necessarily censor these patients in studies of time-varying exposures, we are likely to incur at most a modest selection bias. 相似文献
1000.
Eric M. Lind Elizabeth Borer Eric Seabloom Peter Adler Jonathan D. Bakker Dana M. Blumenthal Mick Crawley Kendi Davies Jennifer Firn Daniel S. Gruner W. Stanley Harpole Yann Hautier Helmut Hillebrand Johannes Knops Brett Melbourne Brent Mortensen Anita C. Risch Martin Schuetz Carly Stevens Peter D. Wragg 《Ecology letters》2013,16(4):513-521
Plant growth can be limited by resource acquisition and defence against consumers, leading to contrasting trade‐off possibilities. The competition‐defence hypothesis posits a trade‐off between competitive ability and defence against enemies (e.g. herbivores and pathogens). The growth‐defence hypothesis suggests that strong competitors for nutrients are also defended against enemies, at a cost to growth rate. We tested these hypotheses using observations of 706 plant populations of over 500 species before and following identical fertilisation and fencing treatments at 39 grassland sites worldwide. Strong positive covariance in species responses to both treatments provided support for a growth‐defence trade‐off: populations that increased with the removal of nutrient limitation (poor competitors) also increased following removal of consumers. This result held globally across 4 years within plant life‐history groups and within the majority of individual sites. Thus, a growth‐defence trade‐off appears to be the norm, and mechanisms maintaining grassland biodiversity may operate within this constraint. 相似文献