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61.
The effect of selected salts (NaCl, NaBr, NaI) with increasingly chaotropic anions on gluten prolamin secondary structure and dynamics was studied using FT‐IR and NMR spectroscopy. FT‐IR spectra indicated a small increase in intermolecular β‐sheet structures when gluten samples were incubated with low levels of NaCl and NaBr. The β‐sheet content remained constant with further NaCl addition, but was reduced again with higher NaBr concentrations. NaI addition generally reduced the amount of β‐sheet and increased the amount of β‐turns. From these data, it could be concluded that, in the presence of chaotropic anions, the proteins tended to prefer the β‐turn helix structure characteristic of glutenin subunits in solution. 1H‐NMR relaxation showed that the molecules were more rigid in 1M NaCl than in pure water, and that the mobility of the prolamins in the presence of 1M NaCl, NaBr, and NaI increased in accordance with the position of the anions in the Hofmeister series. The increase in mobility appeared to be associated with the increase in β‐turn helical structures.  相似文献   
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Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement.  相似文献   
63.
Pythium root rot (PRR) caused by Pythium spp. is an important root rot disease affecting common bean productivity. The objective of this study was to conduct a genome-wide association analysis of resistance to PRR in the common bean of Andean gene pool using single nucleotide polymorphism (SNP) markers. About 260 genotypes of the Andean diversity panel (ADP) were evaluated under screen house conditions using Pythium ultimum isolate MS61 in Uganda. Sixteen significant signals for resistance to PRR were detected on chromosomes Pv01, Pv02, Pv04, Pv05 and Pv09 using 260K GBS-based and 6K Beadchip SNPs. Common significant signals were detected on Pv02 and Pv09 for PRR. Positional candidate genes associated with significant SNPs on Pv02 were Phvul.002G119700, 16.97 kb near marker S02_25507837 (25.50 Mb), encoding Subtilase family protein, and Phvul.002G278400 near marker ss715645959 (44.79 Mb) encoding Defensin-like (DEFL) protein involved in plant defence responses. Based on the relatively high heritability estimates observed for PRR in this study, significant SNP markers associated with genomic regions for resistance to PRR could be validated for marker-assisted breeding in Andean beans.  相似文献   
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OBJECTIVES: To describe the clinical signs and histopathologic features of renal allograft rejection in cats, and to provide a historical, untreated control group for use in future studies of feline renal allograft rejection. ANIMALS: Fourteen adult research cats. METHODS: Renal transplantation and bilateral nephrectomy were performed in pairs of immunogenically mismatched cats. A physical examination was performed, and packed cell volume, total protein, and plasma creatinine concentrations were measured each day after surgery. The cats were euthanatized when plasma creatinine concentration exceeded 7 mg/dL or when weight loss exceeded 20%. Renal histopathology was scored according to the Banff 97 criteria by 3 pathologists. RESULTS: Nine cats completed the study. Plasma creatinine exceeded 7 mg/dL in 5 cats, weight loss exceeded 20% in 3 cats, and 1 cat was found dead. Clinical signs in cats with rejection were nonspecific or absent. Rectal temperature decreased by 0.8 +/- 0.5 degrees C in the 24 hours before euthanasia. The pathologists agreed on the allograft histopathologic category in 6 of 9 cats. The histologic consensus was acute/active rejection in 8 cats and normal in 1 cat. Median survival time of the 8 cats with histologically confirmed allograft rejection was 23 days (range, 8-34 days). CONCLUSIONS AND CLINICAL RELEVANCE: Renal allograft rejection is associated with minimal clinical signs. Therefore, plasma creatinine concentration should be measured routinely in patients with a functioning allograft. An increase in plasma creatinine concentration is highly suspicious for allograft rejection, although a biopsy of the renal allograft is needed for definitive diagnosis.  相似文献   
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Background

Long‐duration beta‐lactam antibiotics are used for empirical treatment in female dogs with uncomplicated bacterial cystitis. However, women with bacterial cystitis are treated with short‐duration potentiated sulfonamides because longer courses of beta‐lactams result in lower cure and higher recurrence rates.

Hypothesis/Objectives

Short‐duration potentiated sulfonamide treatment is more efficacious than long‐duration beta‐lactam treatment in achieving clinical and microbiological cures in female dogs with uncomplicated bacterial cystitis.

Animals

Thirty‐eight client‐owned female dogs.

Methods

Randomized, double‐blinded, placebo‐controlled clinical trial. Dogs were treated with TMPSMX (15 mg/kg PO q12h for 3 days followed by a placebo capsule PO q12h for 7 days; Group SDS; n = 20) or cephalexin (20 mg/kg PO q12h for 10 days; Group LDBL; n = 18). Dogs were monitored for clinical and microbiological cure during treatment and at short‐ and long‐term follow‐up.

Results

No statistically significant differences were found between treatment groups in clinical cure rates after 3 days of treatment (89% SDS, 94% LDBL; P = 1.00) and 4 days (85% SDS, 72% LDBL; P = .44) or >30 days (50% SDS, 65% LDBL; P = .50) after conclusion of treatment or in microbiological cure rates 4 days (59% SDS, 36% LDBL; P = .44) or >30 days (44% SDS, 20% LDBL; P = .40) after conclusion of treatment.

Conclusions and Clinical Importance

We did not identify a difference in cure rates between short‐duration sulfonamide and long‐duration beta‐lactam treatments in female dogs with uncomplicated cystitis. Long‐term cure rates in both treatment groups were low. In some female dogs, “uncomplicated” bacterial cystitis may be more complicated than previously recognized.  相似文献   
69.
Despite its vigor, agrifood studies research faces two fault lines: the durability of disciplines, and challenges in engaging non-academic stakeholders. In this essay, I use the concept of boundary work from social studies of science and technology to reflect on the challenges and opportunities for more engaged interdisciplinary research in agrifood studies. I draw on recent field visits to several “sustainable food chain” research projects funded through the Rural Economy and Land Use Programme (RELU), an innovative interdisciplinary research initiative of the UK Research Councils, to highlight the contradictory nature of boundary work in interdisciplinary research. Involving efforts both to bridge interfaces and to separate, exclude and manage other disciplines or stakeholders, boundary work is inherent to interdisciplinarity. Innovations in the organizational culture of projects and in the larger structural context for research can multiply the more generative potential of boundary work, and also yield more and better interdisciplinary research in agrifood studies.
C. Clare HinrichsEmail:
  相似文献   
70.
Canine transmissible venereal tumor (CTVT) is an infectious cell line circulating in many feral dog populations. It originated once, about 10,000 years ago. Phylogenetic analyses of mitochondrial sequences from dogs, wolves, and a geographically diverse collection of CTVT samples indicate that the cancer has periodically acquired mitochondria from its host. We suggest that this may be because the cancer's own mitochondria have a tendency to degenerate, due to high mutation rates and relaxed selection, resulting in host mitochondria being more fit.  相似文献   
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