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The cryostoring of embryogenic tissue of the date palm (Phoenix dactylifera L. cv. Sagai) was examined through dehydrated-encapsulation, vitrification, and vitrification-encapsulation. The most extreme regeneration rate (53.33%) of epitomized, cryostored liquid nitrogen (+LN) treated embryos was observed when pre-embryonic masses were hatched with 0.5 M sucrose for 48 h pursued by 6 h air drying out. The most noteworthy survival rate (80.0%) of epitomized, cryopreserved embryonic cluster came about when calli were hatched with 0.3 or 0.7 M sucrose for 48 h pursued by four hours of lack of hydration, or with 0.5 M sucrose for 48 h without air drying out or with 2 h of air drying out. Following cryopreservation utilizing the embodiment vitrification convention, the most astounding survival (86.7%) as well as the greatest growth (46.7%) was accomplished when the typified vitrified, cryopreserved calli were treated with Vitrification Solution 2 for plants (PVS2) for 60 min at 25 °C. Cryopreservation utilizing the vitrification convention brought about the most extreme recuperation of 53.3%, when vitrified-cryopreserved calli were subjected to PVS2 solution for 30 min at 25 °C. Most extreme (40%) regeneration of vitrified, cryopreserved embryonic calli was seen when these calli were treated with PVS2 solution for 60 min at 25 °C. The outcome got amid this investigation of regrowth after cryopreservation of the cv. Sagai was over the base suitable for a cryo-germplasm bank. Recovery and regrowth were above 30% for all the techniques developed for the cv. Sagai.  相似文献   

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During the recent years, ethomedicine has attracted a great deal of attention among the investigators throughout the world. Although ethnomedicine seeks, in the first place, to compensate for a biological need through providing cures for disorders, it, however, is of a cultural nature, too, in that it investigates people's behaviors and reactions toward health and the issues related to it. Consequently, traditional health must be counted as a component of a society's culture. Investigations of people's views toward traditional medicine are capable of throwing light on acquaintance with their conducts, customs, traditions and behaviors, as well as the social-economic conditions prevailing in their environment. In addition, such investigations of public medicine bring about familiarities with gradual developments in traditional medical methodologies as introduced by culture, economic, or social factors, first into the society, then medicine. Familiarizations with cultural diversities in relation to medicine are the end results. The present paper comprise an anthropological approach toward investigation of ethnomedical practiced by women of Uremia (North-West, Iran).  相似文献   

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Summary Petiolar felt-sheath of palm (Livistona chinensis) has been successfully used as a new biostructural matrix for the immobilization of fungal hyphae. The reticulated felt-sheath is made up of fibrous bundles having irregularly scattered membranous-foliose and fibrous outgrowths woven into a cohesive multi-layered mesh. Immobilization of Aspergillus niger was achieved with both spore and hyphal suspensions as the inoculum. Growth in immobilized cultures was 19% greater than in free cultures.  相似文献   

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The aim of this study was to evaluate the antiviral potential of methanolic extract (ME) of Achyranthes aspera, an Indian folk medicine and one of its pure compound oleanolic acid (OA) against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). The ME possessed weak anti-herpes virus activity (EC50 64.4 μg/ml for HSV-1 and 72.8 μg/ml for HSV-2). While OA exhibited potent antiherpesvirus activity against both HSV-1 (EC50 6.8 μg/ml) and HSV-2 (EC50 7.8 μg/ml). The time response study revealed that the antiviral activity of ME and OA is highest at 2–6 h post infection. The infected and drug-treated peritoneal macrophage at specific time showed increased level of pro-inflammatory cytokines (IL6 and IL12). Further, the PCR of DNA from infected cultures treated with ME and OA, at various time intervals, failed to show amplification at 48–72 h, similar to that of HSV infected cells treated with acyclovir, indicating that the ME and OA probably inhibit the early stage of multiplication (post infection of 2–6 h). Thus, our study demonstrated that ME and OA have good anti-HSV activity, with SI values of 12, suggesting the potential use of this plant.  相似文献   

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Tahina J.Dransf. & Rakotoarinivo, gen. nov. (Arecaceae) is described as a new genus from north-western Madagascar, with a single species T. spectabilis J.Dransf. & Rakotoarinivo, sp. nov. Tahina is included within tribe Chuniophoeniceae of subfamily Coryphoideae, based on the strictly tubular imbricate rachilla bracts, the flowers grouped in cincinni with tubular bracteoles, and the stalk-like base to the corolla. This position is corroborated by evidence from plastid DNA. Lamina anatomy is discussed in detail, and similarities with and differences from the other members of Chuniophoeniceae are discussed. Based on the ecological characteristics of the single locality, predictions are made on where else it may occur in Madagascar.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 79–91.  相似文献   

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Objective: The relationship between smoking and the development of meningioma has been investigated in several epidemiological studies. However, the results of these studies are inconsistent. We conducted a meta-analysis in order to identify any potential association. Methods: PubMed, the Cochrane Library, and EMBASE databases were searched to identify relevant articles that investigated the risk of meningioma following cigarette smoking. Two researchers evaluated study eligibility and extracted the data independently, and disagreements were resolved by discussion. The variables used to estimate the pooled risk of smoking in meningioma development were the multivariate-adjusted risk estimates presented in the literature. Results: Seven case–control and two cohort studies were included in this meta-analysis. The pooled estimated risks associated with ever smoking for meningioma were 1.02 (95% confidence interval (CI): 0.85–1.21) in the case–control studies, 0.93 (95% CI: 0.83–1.04) in the cohort studies and 0.95 (95% CI: 0.87–1.05, P = 0.32) in all studies when the cohort and case–control data were combined. Subgroup analyses suggested that the risk estimates were 1.49 (95% CI: 1.06–2.09, P = 0.02), 0.86 (95% CI: 0.65–1.13), 0.79 (95% CI: 0.50–1.25) and 0.84 (95% CI: 0.69–1.03) for men, women, current and past smoking respectively. Sensitivity analyses restricted to studies with different adjustments for confounders yielded similar results. No evidence of publication bias was observed. Conclusion: Our meta-analysis suggests that there is no association between ever smoking and the risk of meningioma. However, a small but significant risk elevation is present among men smokers.  相似文献   

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Pancreatic cancer represents a serious public health problem worldwide. Due to its high mortality, efforts on identifying risk factors are very important since only a few risk-related factors have been well established. The present study aimed to address this knowledge gap by estimating the risk of pancreatic cancer associated with opium use. We performed a thorough literature search of PubMed, Web of Science and Scopus, which yielded 3 case-control and 1 cohort study which were included in the analysis. A meta-analysis was conducted using the DerSimonian and Laird inverse-variance approach as the random effects method. The pooled risk ratio for pancreatic cancer in opium users was significantly increased (RR=1.98, 95 % CI 1.33–2.96, p = 0.0008) compared to never users. Subgroup analyses identified a significantly increased risk for pancreatic cancer in men (RR=1.74, 95 % CI 1.22–2.47, p = 0.002), in persons who consumed both raw teriak and refined shireh opium (RR=4.21, 95 % 1.27–13.93, p = 0.02) and in persons who smoked opium (RR=4.21, 95 % 1.27–13.93, p = 0.02). The findings of this study will help in efforts aimed at prevention of pancreatic cancer. Still, further epidemiological research is necessary.  相似文献   

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Background  

stroke is the main cause of disability in high-income countries, and ranks second as a cause of death worldwide. Patients with acute stroke are at risk for infections, but reported post-stroke infection rates vary considerably. We performed a systematic review and meta-analysis to estimate the pooled post-stroke infection rate and its effect on outcome.  相似文献   

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This study reports on the detection of additional expressed sequence tags (EST) derived simple sequence repeat (SSR) markers for the oil palm. A large collection of 19243 Elaeis guineensis ESTs were assembled to give 10258 unique sequences, of which 629 ESTs were found to contain 722 SSRs with a variety of motifs. Dinucleotide repeats formed the largest group (45.6%) consisting of 66.9% AG/CT, 21.9% AT/AT, 10.9% AC/GT and 0.3% CG/CG motifs. This was followed by trinucleotide repeats, which is the second most abundant repeat types (34.5%) consisting of AAG/CTT (23.3%), AGG/CCT (13.7%), CCG/CGG (11.2%), AAT/ATT (10.8%), AGC/GCT (10.0%), ACT/AGT (8.8%), ACG/CGT (7.6%), ACC/GGT (7.2%), AAC/GTT (3.6%) and AGT/ACT (3.6%) motifs. Primer pairs were designed for 405 unique EST-SSRs and 15 of these were used to genotype 105 E. guineensis and 30 E. oleifera accessions. Fourteen SSRs were polymorphic in at least one germplasm revealing a total of 101 alleles. The high percentage (78.0%) of alleles found to be specific for either E. guineensis or E. oleifera has increased the power for discriminating the two species. The estimates of genetic differentiation detected by EST-SSRs were compared to those reported previously. The transferability across palm taxa to two Cocos nucifera and six exotic palms is also presented. The polymerase chain reaction (PCR) products of three primer-pairs detected in E. guineensis, E. oleifera, C. nucifera and Jessinia bataua were cloned and sequenced. Sequence alignments showed mutations within the SSR site and the flanking regions. Phenetic analysis based on the sequence data revealed that C. nucifera is closer to oil palm compared to J. bataua; consistent with the taxanomic classification.  相似文献   

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Oil palm is an important economic crop for Malaysia. Genetic engineering could be applied to produce transgenic oil palms with high value-added fatty acids and novel products to ensure the sustainability of the palm oil industry. Establishment of a reliable transformation and regeneration system is essential for genetic engineering. Biolistic was initially chosen as the method for oil palm transformation as it has been the most successful method for monocotyledons to date. Optimization of physical and biological parameters, including testing of promoters and selective agents, was carried out as a prerequisite for stable transformation. This has resulted in the successful transfer of reporter genes into oil palm and the regeneration of transgenic oil palm, thus making it possible to improve the oil palm through genetic engineering. Besides application of the Biolistics method, studies on transformation mediated by Agrobacterium and utilization of the green fluorescent protein gene as a selectable marker gene have been initiated. Upon the development of a reliable transformation system, a number of useful targets are being projected for oil palm improvement. Among these targets are high-oleate and high-stearate oils, and the production of industrial feedstock such as biodegradable plastics. The efforts in oil palm genetic engineering are thus not targeted as commodity palm oil. Due to the long life cycle of the palm and the time taken to regenerate plants in tissue culture, it is envisaged that commercial planting of transgenic palms will not occur any earlier than the year 2020.  相似文献   

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Palm forests of Copernicia alba are a rare habitat in the semi-arid Chaco of Northwestern Argentina, are centres of high species diversity, and provide key resources for many species. Our goal was to assess the conservation status of five C. alba patches in Northwestern Argentina: Reserve; Embarcación; Palma Sola; Vinalito; and, Talar. We compared patches to identify the sites with greatest conservation needs based on four criteria: population size structure; palm density (of individuals with height >1.30 m); probability of seedlings being browsed; and, presence of potential seed dispersers. We found that three (Embarcación, Reserve, and Talar) out of five sites had palm densities greater than 200 individuals/ha and only one site (Embarcación) showed a reverse J-shaped size structure for height. Reserve and Embarcación had the greatest probability of seedlings being browsed (0.99 ± 0.01 and 0.88 ± 0.12, respectively). A total of 14 potential disperser species of mammals and birds were recorded across the five sites. Only Reserve harboured all of the potential dispersers, but at least two potential disperser species were recorded at the other sites. None of the palm patches studied had an adequate conservation status. However, Embarcación met three out of four criteria, and therefore it can be considered to have the best conservation status in the semi-arid Chaco. Palma Sola and Vinalito have the greatest conservation needs. To conserve C. alba in Northwestern Argentina, strategies are needed that ensure seedling establishment for future populations to reach an adequate density and structure.  相似文献   

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The results of studies investigating the association between ADIPOQ gene polymorphisms and risk of cancer have been inconsistent and often contradictory. The present meta-analysis was conducted in order to overcome the limitations of any individual study and to provide a more precise overall effect estimate. Relevant studies were identified by searching PubMed and Embase for articles published through May 2012. The strength of the relationship between the ADIPOQ gene and risk of cancer was assessed using odds ratios (ORs). Either a fixed-effects or a random-effects model was used to calculate the overall risk estimates. Fifteen studies were included and five SNPs were considered. A significant association was found between SNP rs2241766 and risk of cancer in the recessive genetic model (OR: 0.768, 95% CI: [0.626, 0.942], P = 0.011); a significant relationship was also found between SNP rs1501299 and risk of cancer in both an allele contrast (OR: 0.141, 95%CI: [0.113, 0.176], P < 0.001) and the dominant genetic model (OR: 0.904, 95%CI: [0.830, 0.985], P = 0.021); no association was found with the rs266729, rs822395, or rs822396 SNPs. Adjusted ORs were also considered, but no statistically significant association was found in homozygote contrasts for any of the five SNPs after adjustment. Our results suggest that two polymorphisms, SNP rs2241766 and SNP rs1501299, of the ADIPOQ gene may be associated with reduced risk of cancer. However, the overall strength of association is mild to moderate, and additional well-designed studies are needed to confirm the present conclusion.  相似文献   

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The taller people are, the more money they tend to earn. This phenomenon is widely known as the height premium. However, it is not yet known whether the height premium is universal, or whether it varies by context. To that end, a systematic review of the literature was performed. Five databases were searched until August 2020. Ultimately, a list of 42 studies were included in a narrative synthesis, and 17 studies were included in a meta-analysis. Based on the meta-analysis, we found evidence that the height premium varied by context: the height premium was smaller in the U.S. and Australia, and larger in Latin America and Asia. Within geographies, there appeared to be a larger height premium for men than for women. Cultural factors, labor market structures and biology may play a role in determining the strength of the height premium.  相似文献   

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生物炭提高土壤磷素有效性的整合分析   总被引:4,自引:0,他引:4  
生物炭改善土壤肥力和提高作物产量的作用与土壤磷素有效性的提高密切相关,但是关于生物炭添加对土壤磷素有效性影响的定量效应尚不明确。本研究对95篇符合条件的文献中的507组数据进行整合分析,以评估生物炭添加对土壤磷素有效性的定量影响。结果表明: 不论生物炭原料、制备温度、C/N、施用量、配施化肥与否,以及土壤质地、pH、有机碳含量如何变化,生物炭添加均使土壤有效磷含量显著提高,平均较不添加对照提高57.6%。同时,生物炭添加促进了作物对磷的利用,但植株含磷量对不同添加条件下生物炭的响应程度基本上均低于土壤有效磷,部分条件下未达到显著水平,平均响应比为30.6%。在砂质和壤质土壤中,添加拥有较多灰分的畜禽粪便生物炭,以及较低C/N、低温裂解的碱性生物炭、较大施用量对增加土壤有效磷和植株磷含量更有效。作为土壤磷素循环的主要酶,生物炭添加使碱性磷酸酶活性平均增加2.8%,而酸性磷酸酶活性则平均降低17.8%。总体上,生物炭对土壤有效磷和植株磷含量有显著的正向效应,但对土壤磷酸酶活性的影响较小,磷素有效性的提高可能主要源于生物炭自身携带较高含量的有效磷组分。  相似文献   

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