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81.
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83.
Britt-Marie Sundblad Sven-Arne Jansson Lennarth Nystr?m Peter Arvidsson Bo Lundb?ck Kjell Larsson 《PloS one》2013,8(12)
Background
Little is known about the management of patients suffering from chronic obstructive pulmonary disease (COPD) during the last years of life. The aim of the study was to describe how management of COPD is performed in Sweden during the last two years of life.Methods
From the nationwide Cause of Death register all individuals with COPD as the underlying cause of death during two years were identified in one sparsely and one densely populated area of Sweden. Data were collected from medical records using a pre-defined protocol, especially developed for this purpose.Results
Of 822 individuals with COPD as underlying cause of death, medical records from 729 were available. The COPD diagnosis was based on lung function measurements in approximately half of the patients and median age at COPD diagnosis was 74 years (range 34-95). Women died at younger age, median 78 years (range 52-96) than did men (80 years (51-99)). The median survival time from diagnosis to death was 6 years in men and women in both areas. Among women and men 8.3% and 4.3% were never smokers, respectively. The structure of COPD management differed between the two areas, with utilization of physiotherapists, dieticians and working therapists being more used in the northern area, likely because of differences in accessibility to care institutions.Conclusions
In Sweden COPD is mostly diagnosed late in life and often not verified by lung function measurements. Opposite to the general population, women with COPD die at a lower age than men. 相似文献84.
Daniel W. Nebert Kjell Wikvall Walter L. Miller 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1612)
There are 18 mammalian cytochrome P450 (CYP) families, which encode 57 genes in the human genome. CYP2, CYP3 and CYP4 families contain far more genes than the other 15 families; these three families are also the ones that are dramatically larger in rodent genomes. Most (if not all) genes in the CYP1, CYP2, CYP3 and CYP4 families encode enzymes involved in eicosanoid metabolism and are inducible by various environmental stimuli (i.e. diet, chemical inducers, drugs, pheromones, etc.), whereas the other 14 gene families often have only a single member, and are rarely if ever inducible or redundant. Although the CYP2 and CYP3 families can be regarded as largely redundant and promiscuous, mutations or other defects in one or more genes of the remaining 16 gene families are primarily the ones responsible for P450-specific diseases—confirming these genes are not superfluous or promiscuous but rather are more directly involved in critical life functions. P450-mediated diseases comprise those caused by: aberrant steroidogenesis; defects in fatty acid, cholesterol and bile acid pathways; vitamin D dysregulation and retinoid (as well as putative eicosanoid) dysregulation during fertilization, implantation, embryogenesis, foetogenesis and neonatal development. 相似文献
85.
Temperature sums are widely used to predict the seasonal timing of yearly recurring biological events, such as flowering, budburst, and hatching. We use a classic energy allocation model for annual plants to compare a strategy for reproductive timing that follows a temperature sum rule (TSR) with a strategy that follows an optimal control rule (OCR) maximizing reproductive output. We show that the OCR corresponds to a certain TSR regardless of how temperature is distributed over the growing season as long as the total temperature sum over the whole growing season is constant between years. We discuss such scenarios, thus outlining under which type of variable growth conditions TSR maximizes reproductive output and should be favored by natural selection. By providing an ultimate explanation for a well‐documented empirical pattern this finding enhances the credibility of temperature sums as predictors of the timing of biological events. However, TSR and OCR respond in opposite directions when the total yearly temperature sum changes between years, representing, for example, variation in the length of the growing season. Our findings have implications for predicting optimal responses of organisms to climatic changes and suggest under which conditions natural selection should favor photoperiod versus temperature control. 相似文献
86.
Samyn B Sergeant K Carpentier S Debyser G Panis B Swennen R Van Beeumen J 《Journal of proteome research》2007,6(1):70-80
We report the use of chemical derivatization with MALDI-MS/MS analysis for de novo sequence analysis. Using three frequently used homology-based search algorithms, we were able to identify more than 40 proteins from banana, a nonmodel plant with unsequenced genome. Furthermore, this approach allowed the identification of different isoforms. We also observed that the identification score obtained varied according to the position of the peptide sequences in the query using the MS-Blast algorithm. 相似文献
87.
Pérez de la Mora M Jacobsen KX Crespo-Ramírez M Flores-Gracia C Fuxe K 《Neurochemical research》2008,33(8):1618-1633
The amygdala plays a key role in anxiety. Information from the environment reaches the amygdaloid basolateral nucleus and
after its processing is relayed to the amygdaloid central nucleus where a proper anxiogenic response is implemented. Experimental
evidence indicates that in this information transfer a GABAergic interface controls the trafficking of impulses between the
two nuclei. Recent work indicates that interneuronal communication can take place by classical synaptic transmission (wiring
transmission) and by volume transmission in which the neurotransmitter diffuses and flows through the extracellular space
from its site of release and binds to extrasynaptic receptors at various distances from the source. Based on evidence from
our laboratory the concept is introduced that neurotransmitters in the amygdala can modulate anxiety involving changes in
fear learning and memories by effects on receptor mosaics in the fear circuits through wiring and volume transmission modes
of communication.
Special issue article in honor of Dr. Ricardo Tapia. 相似文献
88.
Kjell Sjöberg Gunnar Gunnarsson Hannu Pöysä Johan Elmberg Petri Nummi 《European Journal of Wildlife Research》2011,57(3):505-516
Two main hypotheses proposed to explain the seasonal decline in reproductive performance in birds are (1) deterioration of
environmental conditions and (2) lower parental quality of late breeders. Previous experimental work addressing these hypotheses
generally have problematic biases pertaining to delay of hatching, costs of re-laying and incubation, as well as variation
in the quality of eggs, territories, offspring and parental traits. We address these biases in an experimental test of the
timing hypothesis (i.e. (1) above) in a precocial bird. Using a 2-year cross-over design and game-farm mallard (Anas platyrhynchos) eggs originating from a number of hens and a standardised delay procedure, we introduced early and late broods with a foster
female onto boreal oligotrophic lakes and monitored subsequent duckling survival. Standardised invertebrate sampling was done
concurrently to get a measure of lake-level abundance of aquatic prey, a likely causative agent of putative seasonal difference
in duckling survival. Survival data and covariates (duckling age; days) were analysed by an information theoretic approach.
There was no effect of treatment (i.e. manipulation of hatching date) on duckling survival, which was higher in 2005 than
in 2004. In contrast to observational studies from more seasonal wetlands, our experiment demonstrates that duckling survival
on boreal lakes was not affected by a 12-day delay in hatching date. Since we did not find any consistent trends in abundance
of aquatic prey, i.e. neither clear peaks nor differences between treatment periods, we hypothesise that moderate climate
change has minor effects on resource abundance and hence also on mallard duckling survival in boreal environments. 相似文献
89.
Liver samples from 422 wild moose (Alces alces), 280 roe deer (Capreolus capreolus), and 73 reindeer (Rangifer tarandus) collected by hunters in various localities in Norway, 2002-2003, were analyzed for the essential trace elements cobalt, copper (Cu), manganese (Mn), molybdenum, selenium (Se), and zinc. Significant differences in hepatic concentrations among species were found for all elements except for Mn, and considerable individual and geographic variations were seen. Roe deer had statistically significant lower Se levels (median: 0.51 μg Se/g dry weight) than did moose (0.77 μg Se/g) and reindeer (0.85 μg Se/g). Moose from two coastal municipalities with high precipitation had considerably higher Se concentrations than those from the other localities studied. Seventy-nine roe deer (28%) and 36 moose (9%) had Se concentrations below that regarded as deficient in domestic ruminants. The Se status in roe deer was lower than previously reported in Europe. Moose had a significantly higher Cu (222 μg Cu/g dw) than did roe deer (112 μg Cu/g) and reindeer (105 μg Cu/g). The Cu status of moose and roe deer in Norway are among the highest reported in Europe. However, a suboptimal Se and Cu status was found in moose from Tvedestrand, a population which has suffered from a reduced condition and productivity. The variability in trace element status among hunted cervids, with no apparent signs of deficiency or toxicity, probably reflects adaptations in these wild ruminant species to cope with this. However, subtle clinical signs and lesions are difficult to detect and further research is needed. 相似文献
90.
The color pattern (two areas on each of 20 transverse bands along the dorsal surface of the body) in two reindeer oestrids, Hypoderma tarandi and Cephenemyia trompe (Diptera: Oestridae), was analyzed and compared with that of different bumblebee species found in an oestrid study area in northern Norway. A clustering analysis and multidimensional scaling analysis of the resulting matrix of pairwise similarity coefficients indicated that Bombus lapponicus, B. alpinus, and B. monticola (Hymenoptera: Bombinae) comprise a Mullerian guild whose members serve as Batesian models for H. tarandi, and that B. pratorum, B. jonellus, and B. lucorum comprise a Mullerian guild whose members may serve as Batesian models for C. trompe. The oestrid mimics also resemble their models in size. 相似文献