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61.
Published outcomes for dogs with specifically high‐grade mast cell tumours (MCTs), controlled for clinical stage, are few. Clinical outcomes for 49 dogs with Kiupel high‐grade, clinical stage I, cutaneous MCTs were evaluated. Median survival time (MST) was 1046 days; 1 and 2‐year survival rates were 79.3% and 72.9%, respectively. At study end 24 dogs had died, 23 dogs were alive (median follow‐up 980 days) and 2 dogs were lost to follow‐up. Death was considered MCT‐related in 14 of 20 dogs with a known cause of death. Local tumour recurrence developed in nine dogs (18.4%); regional lymph node metastasis occurred in six dogs (12.2%); and a new MCT developed in 15 dogs (30.1%). Tumour location, histologic margin size and use of chemotherapy did not affect MST; increasing mitotic count (P = .001) and increasing tumour diameter (P = .024) were independently negatively prognostic. Six dogs that developed lymph node metastasis after surgery had worse MST (451 days) than 42 dogs that did not develop metastasis (1645 days); (P < .001). Our study suggests that dogs with local surgical control of clinical stage I histologically high Kiupel grade cutaneous MCT may have a long survival time; especially those with smaller tumours and a lower mitotic count. Our results suggest that evaluation of staging information and mitotic count may be equally helpful as histologic grading when making a prognosis; and highlight the importance of not relying on histologic grade alone when predicting survival for dogs with MCT.  相似文献   
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Sheep poxvirus (SPPV), Goat poxvirus (GTPV) and Lumpy skin disease virus (LSDV) are Capripoxviruses (CaPVs) responsible for causing severe poxvirus disease in sheep, goats and cattle, respectively. Serological differentiation of CaPVs is not possible and strain identification has relied on the implicitly accepted hypothesis that the viruses show well defined host specificity. However, it is now known that cross infections can occur and authentication of identity based on the host animal species from which the strain was first isolated, is not valid and should be replaced with molecular techniques to allow unequivocal strain differentiation. To identify a diagnostic target for strain genotyping, the CaPV homologue of the Vaccinia virus E4L gene which encodes the 30 kDa DNA-dependent RNA polymerase subunit, RPO30 was analyzed. Forty-six isolates from different hosts and geographical origins were included. Most CaPVs fit into one of the three different groups according to their host origins: the SPPV, the GTPV and the LSDV group. A unique 21-nucleotide deletion was found in all SPPV isolates which was exploited to develop a RPO30-based classical PCR test to differentiate SPPV from GTPV that will allow rapid differential diagnosis of disease during CaPV outbreaks in small ruminants.  相似文献   
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Root hairs are single cells that develop by tip growth and are specialized in the absorption of nutrients. Their cell walls are composed of polysaccharides and hydroxyproline-rich glycoproteins (HRGPs) that include extensins (EXTs) and arabinogalactan-proteins (AGPs). Proline hydroxylation, an early posttranslational modification of HRGPs that is catalyzed by prolyl 4-hydroxylases (P4Hs), defines the subsequent O-glycosylation sites in EXTs (which are mainly arabinosylated) and AGPs (which are mainly arabinogalactosylated). We explored the biological function of P4Hs, arabinosyltransferases, and EXTs in root hair cell growth. Biochemical inhibition or genetic disruption resulted in the blockage of polarized growth in root hairs and reduced arabinosylation of EXTs. Our results demonstrate that correct O-glycosylation on EXTs is essential for cell-wall self-assembly and, hence, root hair elongation in Arabidopsis thaliana.  相似文献   
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The genetic relationship among 42 genotypes of finger millet collected from different geographical regions of southern India was investigated using random amplified polymorphic DNA (RAPD), inter simple sequence repeats (ISSR), and simple sequence repeats (SSR) markers. Ten RAPD primers produced 111 polymorphic bands. Five ISSR primers produced a total of 61 bands. Of these, 23 bands were polymorphic. The RAPD and ISSR fingerprints revealed 71.3 and 37.4% polymorphic banding patterns, respectively. Thirty-six SSR primers yielded 83 scorable alleles in which 62 were found to be polymorphic. Out of 36 SSR primers used, 14 primers (46.6%) produced polymorphic bands. The SSR primer UGEP7 produced a maximum number of six alleles. Mean polymorphic information content (PIC) of RAPD, ISSR and SSR were 0.44, 0.28, and 0.14, respectively. Molecular variances among the population were 2, 11, and 1% for RAPD, ISSR, and SSR markers, respectively. SSR produced 99% molecular variance within individuals. RAPD and ISSR markers produced a low level of molecular variance within individuals. The STRUCTURE (model-based program) analysis revealed that the 42 finger millet genotypes could be divided into a maximum of four subpopulations. Based on the Bayesian statistics, each RAPD and SSR marker produced three subpopulations (K=3), while ISSR marker showed four subpopulations (K=4). This study revealed that RAPD and SSR markers could narrow down the analysis of population structure and it may form the basis for finger millet breeding and improvement programs in the future.  相似文献   
68.
Phosphorus (P) is the second most growth limiting macronutrient after nitrogen and plays several important roles in all organisms including plants. In soil, P is available in both organic and inorganic forms. P deficiency reduces the growth and yield of several crop plants. Plants respond to P deficiency by the phenotypic changes especially by the modification of root architecture. Molecular marker‐assisted breeding (MAB) has been proposed as an important tool to identify and develop improved varieties of crop plants with efficient P‐use efficiency (PUE). Identification of quantitative trait loci (QTLs) for traits related to PUE has been considered as the first step in marker‐assisted selection (MAS) and improvement of crop yield programmes. In this review, we describe in detail on architectural changes of roots under P deficiency that are reported in various crops and discuss the efforts made to improve PUE using molecular marker tools. Details on QTLs identified for low P‐stress tolerance in various crop plants are presented. These QTLs can be used to improve PUE in crop plants through MAS and breeding, which may be beneficial to improve the yields under P‐deficient soil. Development of new and improved varieties using MAB will limit the use of non‐renewable fertilizers and improve PUE of key crop plants in low input agriculture.  相似文献   
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Western Ghats, one of the megadiversity hotspots, hold a rich treasure of diversity in Momordica L. comprising M. charantia var. muricata, M. charantia var. charantia, M. dioica and M. sahyadrica. Vernacular names of these species vary from place to place. Traditional uses of these species comprising food, medicinal and cosmetic, culinary preparations, vernacular names in local dialects and taboos and religious beliefs relating to their domestication and folk taxonomy are dealt with in this paper.  相似文献   
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