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Eighteen genotypes of Brassica napus were crossed to a cytoplasmic male sterile (CMS) line of B. napus BO 15 carrying B. tournefortii cytoplasm (‘tour’ cytoplasm). Fourteen genotypes were found to be stable maintainers of the ‘tour’ CMS. Of the remaining four genotypes, GSL-1 and ‘Asahi-natane’ were found to be heterozygous and ‘Mangun’ and ‘Yudal’ were homozygous for the restorer gene. Analysis of the F1 and F2 progenies of (CMS) BO 15 בMangun’ and (CMS) BO 15 בYudal’ showed that fertility restoration is controlled by a single dominant gene. The availability of a number of stable maintainer lines and the simple inheritance pattern of fertility restorer gene makes ‘tour’ CMS a useful system for hybrid seed production in rapeseed.  相似文献   
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The present study was on assessment of the anti-parasitic activities of nickel nanoparticles (Ni NPs) against the larvae of cattle ticks Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum (a.) anatolicum (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, Culex quinquefasciatus and Culex gelidus (Diptera: Culicidae). The metallic Ni NPs were synthesized by polyol process from Ni-hydrazine as precursor and Tween 80 as both the medium and the stabilizing reagent. The synthesized Ni NPs were characterized by Fourier transform infrared (FTIR) spectroscopy analysis which indicated the presence of Ni NPs. Synthesized Ni NPs showed the X-ray diffraction (XRD) peaks at 42.76°, 53.40°, and 76.44°, identified as 1 1 1, 2 2 0, and 2 0 0 reflections, respectively. Scanning electron microscopy (SEM) analysis of the synthesized Ni NPs clearly showed that the Ni NPs were spherical in shape with an average size of 150 nm. The Ni NPs showed maximum activity against the larvae of R. (B.) microplus, H. a. anatolicum, A. subpictus, C. quinquefasciatus and C. gelidus with LC50 values of 10.17, 10.81, 4.93, 5.56 and 4.94 mg/L; r2 values of 0.990, 0.993, 0.992, 0.950 and 0.988 and the efficacy of Ni-hydrazine complexes showed the LC50 values of 20.35, 22.72, 8.29, 9.69 and 7.83 mg/L; r2 values of 0.988, 0.986, 0.989, 0.944 and 0.978, respectively. The findings revealed that synthesized Ni NPs possess excellent larvicidal parasitic activity. To the best of our knowledge, this is the first report on larvicidal activity of blood feeding parasites using synthesized Ni NPs.  相似文献   
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Contagious caprine pleuropneumonia (CCPP) is a serious disease of goats, occasionally sheep and wild ruminants, caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp). The disease is characterized by severe serofibrinous pleuropneumonia, very high morbidity (~100%), and mortality (80–100%). CCPP affects goats in more than 40 countries of the world thereby posing a serious threat to goat farming around the globe. The characteristic clinical signs of CCPP are severe respiratory distress associated with sero-mucoid nasal discharge, coughing, dyspnea, pyrexia, pleurodynia, and general malaise. In later stages, severe lobar fibrinous pleuropneumonia, profuse fluid accumulation in pleural cavity, severe congestion of lungs and adhesion formation is observed. Mycoplasmal antigen interactions with host immune system and its role in CCPP pathogenesis are not clearly understood. CCPP is not a zoonotic disease. Diagnosis has overcome cumbersome and lengthy conventional tests involving culture, isolation, and identification by advanced serological (LAT, cELISA) or gene-based amplification of DNA (PCR, RFLP, and hybridization) and sequencing. The latex agglutination test (LAT) is rapid, simple, and better test for field and real-time diagnosis applicable to whole blood or serum and is more sensitive than the CFT and easier than the cELISA. Moreover, the studies on antibiotic sensitivity and exploration of novel antibiotics (fluoroquinolones, macrolides) can help in better therapeutic management besides preventing menace of antibiotic resistance. Re-visiting conventional prophylactic measures focussing on developing novel strain-based or recombinant vaccines using specific antigens (capsular or cellular) should be the most important strategy for controlling the disease worldwide.  相似文献   
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A quantitative HPLC analysis of the major triterpenoids present in an aqueous extract of powdered neem kernels prepared in the traditional manner was undertaken. The study shows that water extracts contain all the principal triterpenoids in neem kernel though the quantities extracted are much less than in the subsequent extraction with methanol.  相似文献   
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Monocarboxylate transporters (MCTs) support tumour growth by regulating the transport of metabolites in the tumour microenvironment. High MCT1 or MCT4 expression is correlated with poor outcomes in human patients with head and neck squamous cell carcinoma (HNSCC). Recently, drugs targeting these transporters have been developed and may prove to be an effective treatment strategy for HNSCC. Feline oral squamous cell carcinoma (OSCC) is an aggressive and treatment‐resistant malignancy resembling advanced or recurrent HNSCC. The goals of this study were to investigate the effects of a previously characterized dual MCT1 and MCT4 inhibitor, MD‐1, in OSCC as a novel treatment approach for feline oral cancer. We also sought to determine the potential of feline OSCC as a large animal model for the further development of MCT inhibitors to treat human HNSCC. In vitro, MD‐1 reduced the viability of feline OSCC and human HNSCC cell lines, altered glycolytic and mitochondrial metabolism and synergized with platinum‐based chemotherapies. While MD‐1 treatment increased lactate concentrations in an HNSCC cell line, the inhibitor failed to alter lactate levels in feline OSCC cells, suggesting an MCT‐independent activity. In vivo, MD‐1 significantly inhibited tumour growth in a subcutaneous xenograft model and prolonged overall survival in an orthotopic model of feline OSCC. Our results show that MD‐1 may be an effective therapy for the treatment of feline oral cancer. Our findings also support the further investigation of feline OSCC as a large animal model to inform the development of MCT inhibitors and future clinical studies in human HNSCC.  相似文献   
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Recent research point to the Indian wild taxa of Cucumis callosus (Rottler) Cogn. as the wild progenitor of melon (C. melo L.). Overlapping distribution with cultivated and weedy and feral forms of melo and normal fertility of F1 and BC1 generations of its cross with cultivated melon indicate its progenitor status. A perusal of herbarium data indicate its natural distribution pattern in the region comprising Vindhya Hills and Aravalli mountain ranges extending northwards to Indo-Gangetic plains and southwards to the Deccan plateau touching rain shadow areas of Western Ghats. Characterised by drought tolerance and field resistance to a host of pests and diseases, it is conspicuously absent in the high rainfall areas of Western Ghats and upper Himalayan region. Based on its morphological distinction and F1 and BC1 fertility with C. melo, a subspecific rank within C. melo is postulated. First-hand information on its occurrence, distribution and crossability relationship with other Indian taxa of Cucumis are given.  相似文献   
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Two novel xanthones from Garcinia mangostana.   总被引:4,自引:0,他引:4  
The isolation of two novel xanthones isolated from the fruit hulls of Garcinia mangostana is reported. The structures were elucidated by means of spectroscopic analysis.  相似文献   
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The paper reports the results of genetic studies made in four interspecific hybrids of the genus Oryza, and the data are employed to discuss the inter-relationships between the different species. The characters of wild parents were found to be dominant in the F1 hybrids.In O. sativa (variety Fukoku) × O. perennis subsp. balunga, the inheritance of the eight characters studied was found to be of the same nature as that of complementary, modifying, duplicating and polygenic types involving two or three genes. In O. perennis (Cuban type) × O. perennis subsp. balunga, the interesting feature was the occurrence of recessive characters (typical of cultivated rices) in the F2 population, even though the two parents carried the dominant wild characters. This should be possible only by the operation of duplicate genes and such a mode of inheritance was observed for three characters. No definite Mendelian ratios could be got for the remaining five characters studied. The appearance of characters of cultivated rices has been suggested to point to the ability of O. perennis to give rise to O. sativa through natural crossing and selection. In O. glaberrima × O. perennis subsp. balunga, the ten characters studied segregated in monogenic or digenic fashion. When digenic, these characters exhibited complementary or inhibitory factor interactions. In O. glaberrima × O. breviligulata, the simple mode of inheritance in the F2 generation has been suggested to indicate the close relationship of the two species.Some of the general features of the hybrids and segregating populations studied were the vigorous and fertile F1s followed by the appearance of weak and unthrifty plants in the F2 generation and the tendency for the parental characters to inherit together. The appearance of plants looking similar to O. sativa var. fatua in the F2 populations of O. sativa × O. perennis, and of O. stapfii in the F2s of O. glaberrima × O. perennis has been supposed to provide further evidence on the hybrid origin of these two forms.  相似文献   
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