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31.
Summary The pro 2(I) collagen gene has been screened for Bgl II restriction fragment length polymorphisms (RFLPs) in the Finnish population which has a long background of genetic isolation. As genetically isolated populations tend to demonstrate deviations in the degree of heterozygosity, the RFLP markers described in more heterogeneous populations can not be utilized as such in the former. This proved to be the case with Bgl II polymorphism within the pro 2(I) collagen gene, the gene involved in different disorders of connective tissue. This report describes the presence of three new RFLP-loci and the absence of one RFLP-locus, which had been earlier reported from a population with a genetic background remote from the population studied here.  相似文献   
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The effects of ethanol and phenylethanol on the growth of and glycoprotein secretion by Trichoderma reesei were studied. Low levels (1.5%, vol/vol) of ethanol perturbed the glycosylation process, as shown by alterations in the isoelectric profile of the secreted proteins and a reduction in the rate of incorporation of mannose into oligosaccharides. In addition to these effects on posttranslational modification, ethanol drastically lowered the protein secretion level of a hypersecretory strain.  相似文献   
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Hydrobiologia - We use a long time series of catch abundance from a recreational fishery over 116 years to look for population trends in Atlantic salmon, and anadromous (sea trout) and...  相似文献   
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Purpose

An indicator of nutrient use efficiency through the entire food chain has been lacking. This article proposes a nutrient footprint method to estimate the efficiency of using both nitrogen (N) and phosphorus (P) in animal production chains following Life Cycle Assessment (LCA).

Methods

Following the nutrient footprint method of Grönman et al. (2016), we applied the nutrient footprint method to the Finnish beef production and consumption chain. We defined N and P flows associated with the beef chain from a product-specific point of view. The nutrient footprint is a resource efficiency indicator which combines the amount of nutrients captured for use in the production and consumption chain and their nutrient use efficiency (NutUE) either in the primary product or in both the primary + secondary products.

Results and discussion

Each 1000 kg of Finnish beef consumed requires 1700 kg N and 189 kg P during its life cycle. The percentage of virgin nutrient is more than 50% for N, but only 25% for P. NutUE in the primary product and in both primary + secondary products for N is 1% and 47% and for P is 0.2% and 74%, respectively.

Conclusions

The nutrient footprint offers information about NutUE in a simple and comparable form. In transition towards systems with sustainable nutrient use, it is essential to identify hot spots of nutrient leakage to be able to close them and improve food chains.

  相似文献   
36.
Preeclampsia is a pregnancy-related disorder that causes maternal and fetal morbidity and mortality. Its exact inheritance pattern is still unknown, and genome searches for identifying susceptibility loci for preeclampsia have thus far produced inconclusive or inconsistent results. We performed a heterogeneity-based genome search meta-analysis (HEGESMA) that synthesized the available genome scan data on preeclampsia. HEGESMA identifies genetic regions (bins) that rank highly on average in terms of linkage statistics across genome scans (searches). The significance of each bin’s average rank and heterogeneity across scans was calculated using Monte Carlo tests. The meta-analysis involved four genome-scans on general preeclampsia and five scans on severe preeclampsia. In general preeclampsia, 13 bins had significantly high average rank (P rank < 0.05) by either unweighted or weighted analyses, while four of them (2p11.2–2q21.1, 9q21.32–9q31.2, 2p15–2p11.2, 2q32.1–2q35) were formally significant by both analyses. Heterogeneity of bin 2.8 (2q32.1–2q35) was significantly low in both unweighted and weighted analysis (P Q < 0.01). In severe preeclampsia, 10 bins had significantly high average rank by either unweighted or weighted analyses and five of them (3q11.1–3q21.2, 2q37.1–2q37.3, 18p11.32–18p11.22, 2p15–2p11.2, 7q34–7q36.3) were significant by both analyses. Bin 2q37.1–2q37.3 showed marginal low heterogeneity in unweighted and weighted analysis (P Q = 0.06). Results should be interpreted with caution as the p values were modest. Further investigation of these regions by genotyping with additional markers and families may help to direct the identification of candidate genes for preeclampsia.  相似文献   
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Objective: To determine whether acquired obesity or accompanying metabolic changes such as adiponectin deficiency, insulin resistance, dyslipidemia, or visceral fat are associated, independent of genetic influences, with endothelial dysfunction by studying young adult monozygotic (MZ) twin pairs discordant for obesity. Research Methods and Procedures: Nine obesity‐discordant (intra‐pair difference in BMI, 3.8 to 10.1 kg/m2) and nine concordant (0 to 2.3 kg/m2) 24‐ to 27‐year‐old MZ twin pairs were identified from a population‐based FinnTwin16‐sample. Endothelial function was measured by blood flow responses to intrabrachial infusions of an endothelium‐dependent (acetylcholine) and an endothelium‐independent (sodium nitroprusside) vasodilator. Whole body insulin sensitivity was measured using the euglycemic insulin clamp technique, and forearm and body composition were measured with magnetic resonance imaging and DXA. In addition, serum levels of adiponectin, high‐sensitivity C‐reactive protein, and lipids were determined. Results: The heavier co‐twins of the discordant pairs had significantly lower whole body insulin sensitivity than the leaner co‐twins. Blood flows/muscle volume during infusions of acetylcholine and sodium nitroprusside were not altered by obesity. However, intra‐pair differences in serum adiponectin, intra‐abdominal fat, and C‐reactive protein were significantly correlated with those in endothelial function. Only the relationship between intra‐pair differences in adiponectin and endothelial function persisted in multiple linear regression analysis. Obesity‐concordant co‐twins had comparable insulin sensitivity and endothelial function. Discussion: In young adult MZ twins discordant for obesity, acquired adiponectin deficiency rather than obesity per se is an independent correlate of endothelial dysfunction.  相似文献   
39.
Ethylene insensitivity modulates ozone-induced cell death in birch   总被引:6,自引:0,他引:6       下载免费PDF全文
We have used genotypic variation in birch (Betula pendula Roth) to investigate the roles of ozone (O(3))-induced ethylene (ET), jasmonic acid, and salicylic acid in the regulation of tissue tolerance to O(3). Of these hormones, ET evolution correlated best with O(3)-induced cell death. Disruption of ET perception by transformation of birch with the dominant negative mutant allele etr1-1 of the Arabidopsis ET receptor gene ETR1 or blocking of ET perception with 1-methylcyclopropene reduced but did not completely prevent the O(3)-induced cell death, when inhibition of ET biosynthesis with aminooxyacetic acid completely abolished O(3) lesion formation. This suggests the presence of an ET-signaling-independent but ET biosynthesis-dependent component in the ET-mediated stimulation of cell death in O(3)-exposed birch. Functional ET signaling was required for the O(3) induction of the gene encoding beta-cyanoalanine synthase, which catalyzes detoxification of the cyanide formed during ET biosynthesis. The results suggest that functional ET signaling is required to protect birch from the O(3)-induced cell death and that a decrease in ET sensitivity together with a simultaneous, high ET biosynthesis can potentially cause cell death through a deficient detoxification of cyanide.  相似文献   
40.
3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) is a genotoxic chlorination by-product in drinking water. There is some evidence that it has developmental toxic effects in vitro but its potential to cause developmental effects in vivo is not known. The developmental effects were evaluated in Wistar rats. Rats (22-26 dams per dose group) were administered MX by gavage at the dose levels of 3, 30, or 60 mg/kg in water on gestation days 6-19. Control animals received plain water. Clinical signs, body weight, and food and water consumption were recorded for the dams. On gestation day 20, a cesarean section was performed and the ovaries anduterine contents of the dams were examined and the liver, kidneys, spleen, and thyroid glands weighed. The fetuses of all dose groups were weighed, sexed, and observed for external and skeletal malformations and the fetuses of the two highest dose groups were evaluated for visceral malformations. The highest dose, 60 mg/kg of MX, was slightly toxic to the dams. It decreased the corrected body weight gain of dams by 32% and the water consumption by 16-17%. Kidney and liver weights were slightly increased. MX did not affect the number of implantations nor did it cause any resorptions. The body weights of fetuses were not significantly affected. MX did not cause external malformations or skeletal anomalies. Two fetuses at 60 mg/kg and one fetus at 30 mg/kg had major visceral malformations (persistent truncus arteriosus, diaphragmatic hernia, dilated aorta with a stenosis of pulmonary arteries) and two minor artery abnormalities were observed in those animals. The frequency of unilateral displaced testis was slightly higher (9.2%) in the 60-mg/kg dose group than in controls (1.6%). Since the abnormalities did not form a consistent pattern and occurred most at maternally toxic dose, we conclude that MX can be regarded as non-teratogenic.  相似文献   
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