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The date palm is a resilient, socioeconomically valuable desert fruit tree renowned for its heat, drought, and salinity tolerance. Date palm fruits are rich in nutrients and antioxidants, and their beneficial health properties can mitigate current and future food security challenges. However, it is challenging to improve date palm production through conventional breeding methods due to its slow growth. Date palm seeds do not produce true-to-type progeny, and commercial propagation relies on direct organogenesis from maternal tissue. Consequently, numerous economically important and valuable cultivars are lost due to tissue recalcitrance and challenges in inducing cell dedifferentiation and regeneration. Moreover, genetic engineering of date palms is currently impossible due to the lack of a stable genetic transformation protocol. This hampers the development of genetic resources in date palms.  相似文献   
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This paper reports a double-blind trial of a new antianginal drug, perhexiline. Fifty-five patients suffering from angina pectoris were studied for periods of 12 or 24 weeks in a cross-over comparison against a placebo in four centres in the United Kingdom and Ireland. Perhexiline was effective in most patients as judged by reducing the number of anginal attacks in 84% and the consumption of glyceryl trinitrate tablets in 64%. The major side effect, dizziness, noted in one-third of the patients, may be dose/body-weight related. Perhexiline is a valuable new agent for the treatment of patients with angina, especially those who do not respond to other antianginal agents.  相似文献   
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Cancer therapy is facing the big challenge of destroying selectively tumour cells without harming the normal tissues. Chemotherapy was trying from the beginning to kill malignant cells because of their proliferative activity since normal cells are in general quiescent. Meanwhile side effects were produced due to the destruction of some normal cells that need regular proliferation. The discovery of biomarkers led to the identification of molecular targets within tumour cells in order to kill them selectively. Chemistry followed the progress of biomarkers biotechnology by the production of target specific antagonists which were the subject of many patents. Meanwhile novel problems of tumour resistance appeared and made the battle against cancer a non stop development of new strategies and new weapons. As a consequence, paralleled activities of patenting biomarkers and chemical antagonists are continuously generated. The offer of chemistry does not actually limit the efficiency of Targeted therapy but the identification of biomarkers is still missing the exclusive specificity to tumour cells.  相似文献   
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The PIN auxin efflux facilitators: evolutionary and functional perspectives   总被引:2,自引:0,他引:2  
It is widely believed that the PIN proteins are crucial for proper cellular coordination. Since the analysis of the Arabidopsis pin-formed mutant in 1991, and the subsequent cloning of AtPIN1, a further seven members of the family have been discovered. Here, we present an overview of this family of auxin efflux facilitators in monocot and dicot plants, summarizing their evolutionary history, expression profiles and, where appropriate, relating them to protein function.  相似文献   
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The growth response ofCalopogonium caeruleum, a leguminous covercrop in plantation agriculture, to inoculation with two vesicular-arbuscular mycorrhizal (VAM) fungi was investigated in five phosphorus (P)-deficient soils supplied with various levels of rock phosphate. Significant shoot yield increases over the uninoculated controls were obtained in most sterilised or unsterilised soils at all applied P levels, although the inoculant VAM fungi differed in their effectiveness in the soils used. Responses in mycorrhizal root infections, P and nitrogen (N) concentrations in tops and plant nodulation varied. The results are discussed in relation to the edaphic environment of the mycorrhizal association.  相似文献   
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生物入侵过程中的植物-土壤反馈:一种入侵植物的凋落物分解对其本地近缘植物的影响植物入侵可通过正或负的植物-土壤反馈效应改变土壤的生物和非生物性质,从而影响入侵栖息地的土壤理化性质。许多入侵物种的凋落物分解可增加土壤养分,降低本地植物多样性,并导致进一步的植物入侵。关于入侵植物凋落物在不同土壤类型及深度分解及反馈效应的研究依然很少。本研究旨在明确入侵植物南美蟛蜞菊(Sphagneticola trilobata)凋落物在不同土壤类型和不同土壤深度条件下的分解情 况及其对本地近缘植物蟛蜞菊(S. calendulacea)生理生长的影响。将装有南美蟛蜞菊凋落物的尼龙袋加入到不同深度(即0、2、4 和6 cm)的砂土、营养土和粘土中,经6个月的分解后,回收凋落物袋并计算分解速率,随后在凋落物分解处理后的土壤中种植本地蟛蜞菊,并在生长期结束时测量其生理生态指标。研究结果表明,所有处理土壤类型中,凋落物在土壤深度为2和4 cm处分解后显著增加了土壤养分,而对本 地蟛蜞菊的叶片叶绿素、叶氮含量等生长指标表现为负效应。因此,入侵植物南美蟛蜞菊凋落物分解对土壤养分表现为正的反馈效应,而对本地植物蟛蜞菊的生长表现为负效应。我们的研究结果还表明,入侵植物的凋落物分解对土壤和本地物种的影响还因凋落物分解所在的土壤深度而显著不同。未来的研究应侧重于入侵栖息地中更多本地和入侵物种的植物-土壤反馈效应,以及更多土壤类型和土壤深度的入侵植物凋落物效应。  相似文献   
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<正>Plant-parasitic nematodes(PPNs) are destructive pathogens that cause great damage to crops and severely limit food production, hindering our ability to meet the growing worldwide demand for food(Topalovi? and Vesterg?rd,2021). The global crop losses caused by PPNs are estimated to be about 8.8%–14.6% of total crop production and 100–157 billion USD annually(Singh et al., 2013).  相似文献   
10.
BackgroundRetinal microvascular signs may provide insights into the structure and function of small vessels that are associated with renal disease. We examined the relationship of retinal microvascular signs with both prevalent and incident end-stage renal disease (ESRD) in a multi-ethnic Asian population.MethodsA total of 5763 subjects (aged ≥40 years) from two prospective population-based studies (the Singapore Malay Eye Study and the Singapore Prospective Study) were included for the current analysis. Retinopathy was graded using the modified Airlie House classification system. Retinal vascular parameters were measured using computer-assisted programs to quantify the retinal vessel widths (arteriolar and venular caliber) and retinal vascular network (fractal dimension). Data on ESRD was obtained by record linkage with the ESRD cases registered by National Registry of Diseases Office, Singapore. Multi-variable adjusted regression analyses were performed to assess the associations of baseline retinal vascular parameters and prevalent and incident ESRD.ResultsAt baseline, 21(0.36%) persons had prevalent ESRD. During a median follow-up of 4.3 years, 33 (0.57%) subjects developed ESRD. In our analyses, retinopathy was associated with prevalent ESRD (multi-variable adjusted odds ratio [OR], 3.21, 95% confidence interval [CI]: 1.28–8.05) and incident ESRD (multi-variable adjusted hazard ratio [HR], 2.51, 95%CI: 1.14–5.54). This association was largely seen in person with diabetes (HR, 2.60, 95%CI: 1.01–6.66) and not present in persons without diabetes (HR, 1.65, 95%CI: 0.14–18.98). Retinal arteriolar caliber, retinal venular caliber and retinal vascular fractal dimension were not associated with ESRD.ConclusionRetinopathy signs in persons with diabetes are related to an increased risk of ESRD; however, other microvascular changes in the retina are not associated with ESRD.  相似文献   
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