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661.
Effects of errors in range maps on estimates of historical species richness of mammals in Canadian national parks 总被引:1,自引:1,他引:0
Aim Tests for faunal relaxation in reserves, particularly for mammals, have relied on comparisons of current species richness with estimates of species richness derived from historical range maps. However, any range map reflects the extent of occurrence of species and not necessarily the area of occupancy. Thus, estimates of historical species richness might be prone to error introduced by ‘false positives’, that is, a species might be considered to have been present in locations where it actually was not. The effect of such ‘false positives’ could bias statistical tests of faunal relaxation to type I error, and result in estimates of the extent of faunal relaxation in reserves greater than was actually the case. We evaluated the potential for errors in historical range maps to generate inflated estimates of historical species richness of mammals at sites that are reserves today. Location Canadian national parks in the Canadian portion of the Alleghenian‐‐Illinoian mammal province in south‐eastern Canada (the maritime region and parts of southern Québec, Ontario and Manitoba). Methods The effect of varying levels of error in range maps on estimates of historical species richness was tested using geographical information systems (GIS)‐based statistical sampling of simulated historical ranges. Species’ areas of occupancy were simulated to be only 25%, 75% and 95% of published historical species ranges. For each reserve, estimates of historical species richness from these simulated species ranges were then compared with similar, previously published estimates of richness based on published historical species ranges. Results Previous estimates of historical species richness for reserves were inversely and linearly related to the degree of inaccuracy of species ranges. If species ranges were, on average, 5% smaller than the accepted ranges, then estimates of historical species richness agreed with previous estimates in c. 90% of cases. However, if historical ranges were, on average, 25% smaller than those used in previous analyses, then previous historical estimates of species richness may be overestimates in c. 40% of cases. Main conclusions Estimates of the extent of faunal relaxation in reserves that use historical range maps to quantify past species richness appear to be sensitive to even small errors in the degree to which range maps may overestimate ‘area of occupancy’. 相似文献
662.
Vrijheid M Cardis E Ashmore P Auvinen A Gilbert E Habib RR Malker H Muirhead CR Richardson DB Rogel A Schubauer-Berigan M Tardy H Telle-Lamberton M;-Country Study Group 《Radiation research》2008,170(5):661-665
In contrast to other types of leukemia, chronic lymphocytic leukemia (CLL) has long been regarded as non-radiogenic, i.e. not caused by ionizing radiation. However, the justification for this view has been challenged. We therefore report on the relationship between CLL mortality and external ionizing radiation dose within the 15-country nuclear workers cohort study. The analyses included, in seven countries with CLL deaths, a total of 295,963 workers with more than 4.5 million person-years of follow-up and an average cumulative bone marrow dose of 15 mSv; there were 65 CLL deaths in this cohort. The relative risk (RR) at an occupational dose of 100 mSv compared to 0 mSv was 0.84 (95% CI 0.39, 1.48) under the assumption of a 10-year exposure lag. Analyses of longer lag periods showed little variation in the RR, but they included very small numbers of cases with relatively high doses. In conclusion, the largest nuclear workers cohort study to date finds little evidence for an association between low doses of external ionizing radiation and CLL mortality. This study had little power due to low doses, short follow-up periods, and uncertainties in CLL ascertainment from death certificates; an extended follow-up of the cohorts is merited and would ideally include incident cancer cases. 相似文献
663.
Ling-Wei Hsin Xinrong Tian Elizabeth L Webster Andrew Coop Timothy M Caldwell Arthur E Jacobson George P Chrousos Philip W Gold Kamal E Habib Alejandro Ayala William C Eckelman Carlo Contoreggi Kenner C Rice 《Bioorganic & medicinal chemistry》2002,10(1):175-183
A series of compounds related to N-butyl-N-ethyl[2,5,6-trimethyl-7-(2,4,6-trimethylphenyl)pyrrolo[2,3-d]pyrimidin-4-yl]amine (1, antalarmin) have been prepared and evaluated for their CRHR1 binding affinity as the initial step in the development of selective high affinity hydrophilic nonpeptide corticotropin-releasing hormone type 1 receptor (CRHR1) antagonists. Calculated log P (Clog P) values were used to evaluate the rank order of hydrophilicity for these analogues. Introducing oxygenated functionalities (delta-hydroxy or bis-beta-ethereal) into 1 gave more hydrophilic compounds, which had good affinity for the receptor. Introducing an amino group or shortening the alkyl side chain was detrimental to CRHR1 affinity. The alcohol 4-[ethyl[2,5,6-trimethyl-7-(2,4,6-trimethylphenyl)pyrrolo[2,3-d]pyrimidin-4-yl]amino]butan-1-ol (3), bearing a terminal hydroxyl group on an N-alkyl side-chain, showed the highest CRHR1 binding affinity among these compounds (K(i)=0.68 nM), and is one of the highest affinity CRHR1 ligands known. Compounds 3-5, and 8, which are likely to be less lipophilic than 1, have high CRHR1 affinity and may be valuable probes to further study the CRH system. 相似文献
664.
Mehrnoosh Minaeimoghadam Sohrab Imani Mahmud Shojaei Kambiz Larijani Habib Abbasipour 《Archives Of Phytopathology And Plant Protection》2017,50(19-20):1019-1033
The clearwing moth, Paranthrene diaphana Dalla Torre & Strand (Lep.: Sesiidae) is one of the most destructive pests of willow trees in Tehran province which leads to dieback. In this study, female volatile compounds were identified. For this purpose, female volatile substances were extracted using Solid Phase Micro Extraction and then were identified using Head Space Chromatography method. Female insects were assessed separately at ages of 2–4, 4–6 and 6–8 days of preparation. Among the various compounds identified by GC/MS in the volatile compounds of female insect, 27 compounds were introduced while seven combinations have also been produced and released at all ages of insect which include: Pentadecane, Heptadecane, Dodecane, Tetradecane, Hexadecane, Eicosane and Tridecane. The peak area of curve (log scale) and frequency of these compounds, demonstrate that five combinations including: Tetradecane, Hexadecane, Tridecane, Eicosane and Dodecane are more important. In addition, five compounds including: Octadecane, Palmitic acid (Hexadecanoic acid), 9-Octadecenoic acid, Tricosane and Hexacosane have been released only from fourth to the eighth day of adult life. Therefore, it seems that female sex pheromone is a combination of these 12 compounds. 相似文献
665.
Thouraya Ben Ltaief Zaher Drira Jean-Luc Devenon Asma Hamza Habib Ayadi Marc Pagano 《Marine Biology Research》2017,13(3):269-287
The spatial and temporal variability of metazooplankton communities in relation to environmental and trophic factors were studied in the Gulf of Gabes during three periods of increasing thermal stratification in June, July and September. Non-metric multi-dimensional scaling (NMDS) revealed the time and space succession of three zooplankton communities in relation to the degree of thermal stratification. A co-inertia analysis showed the association between these communities and the trophic conditions (abundance and composition of microplankton) driven by stratification. Three divergent communities were evident. The first, characterized by annelid larvae and coastal copepods, was associated with shallow mixed and microplankton-rich water (June, coastal). The second, characterized by euphausiids, amphipods, doliolids and several deep-water copepods, corresponded to highly stratified microplankton-poor water (September). The third, characterized by the most ubiquitous and abundant species, was linked to intermediate water (June deep and July). Temperature and salinity conditions also explained the distribution of key species. Clausocalanus furcatus, Oithona plumifera and Triconia conifera were clearly associated with warm and highly stratified water (September). Enhanced thermal stratification led to higher surface salinity, explaining the emergence of euryhaline taxa such as Oithona plumifera. 相似文献
666.
Shah Muqader Zaneb Hafsa Masood Saima Khan Rifat Ullah Ashraf Saima Sikandar Arbab Rehman Hafiz Faseeh Ur Rehman Habib Ur 《Probiotics and antimicrobial proteins》2019,11(3):931-937
Probiotics and Antimicrobial Proteins - This experiment aimed to investigate the effect of different levels of zinc (Zn) and a probiotic on the growth and intestinal health of broiler chickens. One... 相似文献
667.
Amir Salek Farrokhi Narges Darabi Bahman Yousefi Rafee Habib Askandar Mansoreh Shariati Majid Eslami 《Journal of cellular physiology》2019,234(9):14941-14950
Recent studies demonstrated that a combination of the gut microbiome has the vital effect on the efficacy of anticancer immune therapies. Regulatory effects of microbiota have been shown in different types of cancer therapies such as chemotherapy and immunotherapy. Immune-checkpoint-blocked therapies are the recent efficient cancer immunotherapy strategies. The target of immune-checkpoint blocking is cytotoxic T lymphocyte protein-4 (CTLA-4) or blockade of programmed death-1 (PD-1) protein and its ligand programmed death ligand 1 (PD-L1) that they have been considered as cancer immunotherapy in recent years. In the latest studies, it have been demonstrated that several gut bacteria such as Akkermansia muciniphila, Bifidobacterium spp., Faecalibacterium spp., and Bacteroides fragilis have the regulatory effects on PD-1, PD-L1, and CTLA-4 blocked anticancer therapy outcome. 相似文献
668.
Vahideh Tarhriz Mojgan Bandehpour Siavoush Dastmalchi Elaheh Ouladsahebmadarek Habib Zarredar Shirin Eyvazi 《Journal of cellular physiology》2019,234(3):2134-2142
Ovarian cancer (OC) is the fifth leading cause of cancer-related death among women. The high mortality rate is due to lack of early symptoms, late diagnosis, limited treatment options, and also emerging of drug resistance. Todays, molecular markers have become promising in tumor-targeted therapy. Several molecular markers have been known in OC immunotherapy. Identification of the specific molecular markers with prognostic significance is interested. CD24 is a small sialoglycoprotein which is localized in lipid rafts through its glycosylphosphatidylinositol (GPI) anchor. It has been reported that CD24 is overexpressed in many cancers including OC. Also, CD24 is identified as a cancer stem cell marker in OC. The CD24 expression is associated with the development, invasion, and metastasis of cancer cells. The exact role of CD24 in cancer cells is not clearly understood. Recently, CD24 has been identified as an independent prognostic marker of survival in patients with OC. In this study, we reviewed the molecular targets in OC immune-targeted therapy and also presented an overview of the new molecular marker CD24 and its association with the OC by reviewing the recent literature. 相似文献
669.
Habib Yaribeygi Stephen L. Atkin Niki Katsiki Amirhossein Sahebkar 《Journal of cellular physiology》2019,234(5):5786-5797
Diabetes mellitus is the most prevalent metabolic disorder worldwide. Glycemic control is the main focus of antidiabetic therapy. However, there are data suggesting that some antidiabetic drugs may have intrinsic beneficial renal effects and protect against the development and progression of albuminuria, thus minimizing the risk of diabetic nephropathy. These pharmacological agents can suppress upstream molecular pathways involved in the pathophysiology of diabetes-induced renal dysfunction such as oxidative stress, inflammatory responses, and apoptosis. In this narrative review, the pathophysiology of albuminuria in patients with diabetic nephropathy is discussed. Furthermore, the renoprotective effects of antidiabetic drugs, focusing on albuminuria, are reviewed. 相似文献
670.