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91.
The effects of raccoon (Procyon lotor) rehabilitation on postrelease survivorship are unknown. Raccoon rehabilitation success was measured as differences in prewinter body condition, home range size, distance to manmade structures, and during-winter survival between raccoons in the wild and those who have been rehabilitated. Prewinter body condition did not differ between wild and rehabilitated raccoons, but there was a trend for rehabilitated raccoons to have better body conditions. There was no difference between wild and rehabilitated raccoon adaptive kernel (AK) home range for 95% and 90% AK home ranges, or for core (50% AK) use areas. There was no sex difference in distance traveled from the release site within rehabilitated raccoons. However, rehabilitated raccoons were found significantly closer (49.4 ± 4.7 m) to manmade structures than wild raccoons (92.2 ± 14.4 m), and female raccoons were found significantly closer (64.8 ± 4.5 m) to manmade structures than male raccoons (72.3 ± 17.6 m). The results of this study indicate that raccoons can be successfully rehabilitated, but they may occupy habitat closer to manmade structures than wild raccoons.  相似文献   
92.
Nine out of 22 microsatellite primers tested were successfully amplified on three samples of cod Gadus morhua L. (two contemporary and one archived otolith samples). All loci were polymorphic (5–23 alleles/locus). The average observed heterozygosity across loci and samples was 0.625, ranging from 0.294 to 0.895 at each locus. All loci were under Hardy–Weinberg equilibrium, except PGmo56 that showed significant excess of heterozygotes in all studied samples. The isolated loci were suitable for degraded DNA and therefore useful for conducting a long‐term temporal study with DNA obtained from archived otoliths of cod.  相似文献   
93.
For birds that migrate long distances, maximizing the rate of refueling at stopovers is advantageous, but ambient conditions may adversely influence this vital process. We simulated a 3-day migratory stopover for garden warblers (Sylvia borin) and compared body temperatures (T(b)) and rates of refueling under conditions of a heat wave (T(a)=40 °C by day, and 15 °C at night) with those under more moderate conditions (T(a)=27 °C by day, and 15 °C at night). We measured T(b) with implanted thermo-sensitive radio transmitters. Birds had significantly lower rates of body mass gain on the first day of stopover (repeated measures mixed model ANOVA, p=0.002) affecting body mass during the entire stopover (p=0.034) and higher maximum T(b) during the day when exposed to high T(a) than when exposed to moderate T(a) (p=0.002). In addition, the birds exposed to high T(a) by day had significantly lower minimum T(b) at night than those exposed to moderate daytime T(a) (p=0.048), even though T(a) at night was the same for both groups. We interpret this lower nighttime T(b) to be a means of saving energy to compensate for elevated daytime thermoregulatory requirements, while higher T(b) by day may reduce protein turnover. All effects on T(b) were significantly more pronounced during the first day of stopover than on days two and three, which may be linked to the rate of renewal of digestive function during stopover. Our results suggest that environmental factors, such as high T(a), constrain migratory body mass gain. Extreme high T(a) and heat waves are predicted to increase due to global climate change, and thus are likely to pose increasing constraints on regaining body mass during stopover and therefore migratory performance in migratory birds.  相似文献   
94.
Endorheic lakes of the northern Great Plains encompass a wide range of environmental parameters (e.g., salinity, pH, DOC, Ca, nutrients, depth) that vary 1000‐fold among sites and through the past 2000 years due to variation in basin hydrology and evaporative forcing. However, while many environmental parameters are known to individually influence zooplankton diversity and taxonomic composition, relatively little is known of the hierarchical relationships among potential controls or of how regulatory mechanisms may change in response to climate variation on diverse scales. To address these issues, we surveyed 70 lakes within a 100 000 km2 prairie region to simulate the magnitude of environmental change expected to occur over 100–1000 years and to quantify the unique and interactive effects of diverse environmental parameters in regulating pelagic invertebrate community structure at that scale. Multivariate analyses showed that salinity was the principal correlate of changes in invertebrate composition among lakes, with a sequential loss of taxa between salinities of 4 and 50 g total dissolved solids L?1 until one to two species predominated in highly saline systems. In contrast, changes in the concentrations of Ca2+ and other mineral nutrients exerted secondary controls of invertebrate assemblages independent of salinity, whereas lake depth provided a tertiary regulatory mechanism structuring species composition. In contrast to these large‐scale hierarchical patterns, seasonal surveys (May, July, September) of a subset of 21 lakes in each of 2003–2005 revealed that annual meteorological variation had no measurable effect on pelagic invertebrates, despite large differences in temperature, precipitation, and evaporation arising from regional droughts. Together these findings show that pelagic invertebrate communities in saline lakes are resilient to interannual variability in climate, but suggest that lakes of the northern Great Plains may provide a sensitive model to forecast centennial effects of future climate change.  相似文献   
95.
Rapidly growing animals or those that are recovering from nutritional stress may use exogenous nutrients differently from well fed adults. To test this possibility, we compared the rates of exogenous nutrient oxidation among fledgling, fasted adult, and refed adult zebra finches using a technique called breath testing, where animals are fed (13)C-labeled nutrients and (13)C in the exhaled breath is collected and quantified. In order to identify the possible mechanisms responsible for differences in oxidative kinetics of ingested nutrients, we also compared body mass (m(b)), organ mass, core body temperature (T(b)), and metabolic rate (MR). We found that fasted birds had lower T(b), relative liver and intestine masses, MR, and respiratory exchange ratios (RERs) than fed adults. Adult birds recovering from nutritional stress had much lower rates of exogenous nutrient oxidation than fed birds; this difference was particularly evident for fatty acids. Differences in oxidative kinetics were correlated with reduced RER, m(b), and liver mass, suggesting that previously fasted birds were using recently assimilated nutrients to replenish exhausted fuel stores. Rapidly growing fledglings oxidized exogenous nutrients as quickly as fed adults, despite their significantly lower m(b) and T(b). We suggest that fledglings had higher mass-specific rates of exogenous nutrient oxidation because they must compensate for the relatively low conversion efficiency of feather production and other lean tissue growth, which was not taking place in the adults. Although this study demonstrates that ontogeny and nutritional status influence the way that birds oxidize exogenous nutrients, it also underscores the likelihood that environmental and endogenous factors shape how other types of animals spend the nutrients they ingest.  相似文献   
96.
97.
The neurodevelopmental defects associated with ZIKV infections early in pregnancy are well documented, however the potential defects and long-term consequences associated with milder infections in late pregnancy and perinatal period are less well understood. To model these, we challenged 1 day old (P1) immunocompetent C57BL/6 mice with ZIKV. The animals developed a transient neurological syndrome including unsteady gait, kinetic tremors, severe ataxia and seizures 10–15 days post-infection (dpi) but symptoms subsided after a week, and most animals survived. Despite apparent recovery, MRI of convalescent mice show reduced cerebellar volume that correlates with altered coordination and motor function as well as hyperactivity and impulsivity. Persistent mRNA levels of pro-inflammatory genes including Cd80, Il-1α, and Ifn-γ together with Cd3, Cd8 and perforin (PrfA), suggested persistence of low-grade inflammation. Surprisingly, the brain parenchyma of convalescent mice harbor multiple small discrete foci with viral antigen, active apoptotic processes in neurons, and cellular infiltrates, surrounded by activated astrocytes and microglia as late as 1-year post-infection. Detection of negative-sense strand viral RNA and isolation of infectious virus derived from these convalescent mice by blinded passage in Vero cells confirmed long-term persistence of replicating ZIKV in CNS of convalescent mice. Although the infection appears to persist in defined reservoirs within CNS, the resulting inflammation could increase the risk of neurodegenerative disorders. This raises concern regarding possible long-term effects in asymptomatic children exposed to the virus and suggests that long-term neurological and behavioral monitoring as well as anti-viral treatment to clear virus from the CNS may be useful in patients exposed to ZIKV at an early age.  相似文献   
98.
The electroencephalographic alpha activity of 13 college students was monitored under conditions of darkness or dim light for six sessions, and for a seventh under the opposite condition. Auditory feedback was given for the presence of alpha activity during a 5-min orientation period, and then during ten 2-min trial periods. The results indicated that: (1) alpha production in the presence of feedback did not exceed initial eyes-closed base line production; (2) introducing feedback immediately enhances alpha activity, rather than increasing production gradually; (3) under certain circumstances, dim light is sufficient to suppress alpha; and (4) after many sessions of alpha production in darkness, subjects maintain a given amount of alpha even when visual stimulation is present.  相似文献   
99.
Currently the most sensitive method for localizing lung cancers in central airways is autofluorescence bronchoscopy (AFB) in combination with white light bronchoscopy (WLB). The diagnostic accuracy of WLB + AFB for high grade dysplasia (HGD) and carcinoma in situ is variable depending on physician's experience. When WLB + AFB are operated at high diagnostic sensitivity, the associated diagnostic specificity is low. Raman spectroscopy probes molecular vibrations and gives highly specific, fingerprint‐like spectral features and has high accuracy for tissue pathology classification. In this study we present the use of a real‐time endoscopy Raman spectroscopy system to improve the specificity. A spectrum is acquired within 1 second and clinical data are obtained from 280 tissue sites (72 HGDs/malignant lesions, 208 benign lesions/normal sites) in 80 patients. Using multivariate analyses and waveband selection methods on the Raman spectra, we have demonstrated that HGD and malignant lung lesions can be detected with high sensitivity (90%) and good specificity (65%).

  相似文献   

100.

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.  相似文献   
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