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71.
BackgroundComparative evidence on the burden, trend, and risk factors of cancer is limited. Using data from the Global Burden of Disease (GBD) study, we aimed to assess cancer burden – incidence, prevalence, mortality, disability-adjusted life years (DALYs) – and attributable risk factors for Australia between 1990 and 2015, and to compare them with those of 34 members of the Organisation for Economic Co-operation and Development (OECD).MethodsThe general GBD cancer estimation methods were used with data input from vital registration systems and cancer registries. A comparative risk assessment approach was used to estimate the population-attributable fractions due to risk factors.ResultsIn 2015 there were 198,880 (95% uncertainty interval [UI]: 183,908–217,365) estimated incident cancer cases and 47,562 (95% UI: 46,061–49,004) cancer deaths in Australia. Twenty-nine percent (95% UI: 28.2–29.8) of total deaths and 17.0% (95% UI: 15.0–19.1) of DALYs were caused by cancer in Australia in 2015. Cancers of the trachea, bronchus and lung, colon and rectum, and prostate were the most common causes of cancer deaths. Thirty-six percent (95% UI: 33.1–37.9) of all cancer deaths were attributable to behavioral risks. The age-standardized cancer incidence rate (ASIR) increased between 1990 and 2015, while the age-standardized cancer death rate (ASDR) decreased over the same period. In 2015, compared to 34 other OECD countries Australia ranked first (highest) and 24th based on ASIR and ASDR, respectively.ConclusionThe incidence of cancer has increased over 25 years, and behavioral risks are responsible for a large proportion of cancer deaths. Scaling up of prevention (using strategies targeting cancer risk factors), early detection, and treatment of cancer is required to effectively address this growing health challenge. 相似文献
72.
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74.
E. É. Kolesnikova 《Neurophysiology》2008,40(1):48-52
Results of a comparative study of the sensitivity of the system of respiratory control to increases in the CO2 concentration and the intensity of free-radical processes in young and elderly subjects are described. It is shown that normal
(natural) aging is accompanied by a decrease in the sensitivity of the respiratory system to hypercapnic stimulation and a
parallel significant decrease in the activity of catalase in the blood of examined subjects. Mechanisms responsible for the
modifications of the sensitivity of the system of respiratory control to hypercapnia are discussed; these shifts can be at
least partly related to changes in the intensity of production of free radicals observed in elderly subjects.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 1, pp. 53–57, January–February, 2008. 相似文献
75.
1. Worldwide, the excessive use of insecticides has resulted in field-evolved insecticide-resistant populations of diamondback moth (DBM), Plutella xylostella. A deltamethrin-resistant DBM population from the field was divided into two subpopulations in the laboratory. One population (S-strain) was maintained with no further exposure to insecticides, whereas the other population (R-strain) was maintained under a regime of intermittent selection with deltamethrin. 2. Individuals from both strains were reared at constant temperatures in the range 10–35 °C in the absence of deltamethrin, and the effects of rearing temperature on various traits were investigated. At the time of experimentation, the R-strain was 20-fold more resistant to deltamethrin than the S-strain. 3. Temperature differentially affected developmental time, adult life span, pupal weight, and fecundity of both strains. Although both strains laid eggs after being reared at 10 °C, few of these eggs were fertile. The R-strain developed significantly faster than the S-strain. The integrated performance of the S-strain and R-strain was greatest at 25 and 15 °C, respectively. 4. The present study provides important information on the complexities of the outcomes of the interactions between ectotherms and temperature. Specifically, temperature-trait relationships may not be unimodal, and ectotherm genotypes (in this case insecticide-resistance status) and abiotic stresses can interact with unpredictable outcomes. 5. Current models predicting DBM population dynamics and relative abundance in different locations do not consider different thermal biologies of different genotypes. The present study shows the dramatic effects of environment on many parameters used in these models and will help to enhance their accuracy, and thus their utility. 相似文献
76.
《Fungal biology》2020,124(1):44-53
Alternaria blight is one of the most devastating diseases of rapeseed-mustard caused by a necrotrophic fungus Alternaria brassicae. Lack of satisfactory resistance resource in Brassica is still a main obstruction for developing resistance against Alternaria. In this study, we have selected Brassica juncea, Sinapis alba and Camelina sativa to understand and unravel the mechanism of disease resistance against Alternaria. Histopathological studies showed early onset of necrosis in B. juncea (1 dpi) and delayed in S. alba (2 dpi) and C. sativa (3 dpi) respectively. Early and enhanced production of hydrogen peroxide (H2O2) was observed in C. sativa and S. alba (6 hpi) when compared to B. juncea (12 hpi). An increase in catalase activity was observed in both C. sativa (36 % at 6 hpi) and S. alba (15 % at 12 hpi), whereas it significantly decreased in B. juncea at 6 hpi (23 %), 12 hpi (30 %) and 24 hpi (8 %). Gene expression analysis showed induction of PR-3 and PR-12 genes only in C. sativa and S. alba when compared to B. juncea suggesting their vital role for Alternaria resistance. In contrast, SA marker genes were significantly expressed in B. juncea only which provides evidence of hormonal cross talk in B. juncea during Alternaria infection thereby increasing its susceptibility. 相似文献
77.
Oxidative stress has been linked to the pathogenesis of diabetic nephropathy, the complication of diabetes in the kidney. NADPH oxidases of the Nox family, and in particular the homologue Nox4, are a major source of reactive oxygen species in the diabetic kidney and are critical mediators of redox signaling in glomerular and tubulointerstitial cells exposed to the diabetic milieu. Here, we present an overview of the current knowledge related to the understanding of the role of Nox enzymes in the processes that control mesangial cell, podocyte and tubulointerstitial cell injury induced by hyperglycemia and other predominant factors enhanced in the diabetic milieu, including the renin-angiotensin system and transforming growth factor-β. The nature of the upstream modulators of Nox enzymes as well as the downstream targets of the Nox NADPH oxidases implicated in the propagation of the redox processes that alter renal biology in diabetes will be highlighted. 相似文献
78.
D. F. Roberts 《International Journal of Anthropology》1996,11(2-4):185-191
As a conclusion, this paper reviews briefly the content of the volume. The wealth of demographic data has not been adequately
exploited in anthropology; this is why this publication is valuable in showing attempts to apply demographic data in a variety
of anthropological problems. This symposium has explored many interesting points which we recall here. Yet it has also opened
up a whole range of further questions on the material presented as well as in this broad field. Several directions of research
could be developed, for instance, testing among human populations, over long periods, the ecological thoughts of ecosystems
evolving as a cascade of instabilities, rather than a succession of equilibrium states. Let us also recall the pervasive nature
of demographic facts in topics such as the energy cycle or the genetic structure and evolution of human populations. 相似文献
79.
《Current biology : CB》2022,32(3):645-653.e8
Download : Download video (10MB) 相似文献
80.
Peter J. Carrick 《植被学杂志》2003,14(5):761-772
Abstract. The nearest‐neighbour technique is used to infer competition and facilitation between the three most abundant species in a semi‐arid region of western South Africa. Relationships among the shrubs Leipoldtia schultzei and Ruschia robusta, which are leaf‐succulent members of the Mesembryanthemaceae (‘mesembs’) and Hirpicium alienatum a non‐succulent Asteraceae, were compared on two adjacent sites with different histories of browsing intensity. Competition was more prevalent and more important than facilitation. The only evidence for facilitation was found at the heavily‐browsed site where the palatable Hirpicium was larger under the unpalatable Leipoldtia. Generally the prevalence and importance of competition was reduced at the heavily‐browsed site. Strong evidence was obtained for intraspecific competition in each of the three species; also, competition was evident between the two mesembs, where Leipoldtia was competitively dominant over Ruschia, although neither species inhibited Hirpicium. Minimal competition between the mesembs and the asteraceous shrub was interpreted in terms of differentiation in rooting depth, and competition within the mesembs, in terms of overlap in rooting depth. The mesembs had the bulk of their roots in the top 5 cm of soil, while the asteraceous shrub had the bulk of its roots, and all its fine roots, at greater depths. The shallow‐rooted morphology of the mesembs is well adapted to utilize small rainfall events, which occur frequently in the Succulent Karoo, and do not penetrate the soil deeply. Modifications of existing methods are applied for analysing nearest‐neighbour interactions. 相似文献