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91.
Clinical platelet infusion is primarily used to prevent or stop bleeding, but can also have a role in treating infections or promoting wound healing. The demand for platelets has increased in recent years. However, as platelets can only be stored for short periods, there is a substantial loss due to the products reaching their expiry date. Platelet lyophilization is a particularly valuable and important research field. The purpose of studying the freeze-drying preservation of platelets is to realize the long-term preservation of platelets at room temperature. It is very possible to prepare qualified freeze-dried platelets. However, there are still problems that have not been solved in the process of platelet lyophilization. This review mainly summarizes research progress in the preparation and application of freeze-dried platelets. 相似文献
92.
Availability and contributions of soil phosphorus to forage production of seeded alfalfa in semiarid Loess Plateau 总被引:2,自引:0,他引:2
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The availability of soil phosphorus was studied in response to the forage production of seeded alfalfa (Medicago sativa L.), established by the ridge and furrow water-harvesting technique in the semiarid Loess Plateau of China. The following 5 treatments were set up in this study: (1) conventional cultivation in a flat plot without mulch (CK); (2) plastic mulched ridge with 30 cm width of ridge and furrow (M30); (3) plastic mulched ridge with 60 cm width of ridge and furrow (M60); (4) bare ridge with 30 cm width of ridge and furrow (B30); (5) bare ridge with 60 cm width of ridge and furrow (B60). The forage yield, evapotranspiration (ET), soil organic carbon (SOC), total phosphorus, available phosphorus and the ratio of soil organic C to available P (C/P) were measured in the experiment. Results showed that the positive correlation occurred between the decrease in soil available P and the total forage yield of alfalfa after three-year alfalfa stand. M30 and M60 were higher than those of conventional flat cultivation (CK) by 10.7% and 40.3%, respectively, whereas the yield of two bare treatments (B30 and B60) was lower than that of CK by 14.2% and 28.3%, respectively. After a 3-year alfalfa stand, the trend of the decrease in soil available P was in the order of M60 (55.5%) > M30 (51.5%) > CK (34.6%) > B30 (23.4%) > B60 (17.5%). Moreover, after 3-year alfalfa growth, the C/P ratio increased significantly in all of the treatments by comparing with that before sowing. The C/P ratios of M30 (1165.1) and M60 (1326.1) were significantly higher than those of the other treatments. More interesting finding was that the increase in SOC in dry years promoted the accumulation of soil available P. However, in wet years, the increase of SOC limited the accumulation of soil available P. Therefore, to further increase the forage yield of alfalfa, the effective technique must be developed to increase the soil available P. 相似文献
93.
Liang Zhao Shixiao Xu Yingnian Li Yanhong Tang Xinquan Zhao Song Gu Mingyuan Du Guirui Yu 《生物学前沿》2007,2(3):324-332
Carbon dioxide fluxes of Kobresia humilis and Potentillafruticosa shrub meadows,two typical ecosystems in the Qinghai-Tibet Plateau,were measured by eddy covariance technology and the data collected in August 2003 were employed to analyze the relations between carbon dioxide fluxes and environmental factors of the ecosystems.August is the time when the two ecosystems reach their peak leaf area indexes and stay stable,and also the period when the net carbon absorptions of Kobresia humilis and Potentilla photo flux densities (PPFD),the carbon dioxide-uptake rate of the Kobresia humilis meadow is higher than that of the Potentilla fruticosa shrub meadow;where the PPFD are rates of the two ecosystems declined as air temperature increased,but the carbon dioxide uptake rate of the Kobresia humilis meadow decreased more quickly (-0.086) than that of the Potentilla fruticosa shrub meadow (-0.016).Soil moistures exert influence on the soil respirations and this varies with the vegetation type.The daily carbon dioxide absorptions of the ecosystems increase with increased diurnal temperature differences and higher diurnal temperature differences result in higher carbon dioxide exchanges.There exists a negative correlation between the vegetation albedos and the carbon dioxide fluxes. 相似文献
94.
Fakhreddin Salehi 《Journal of applied microbiology》2022,132(4):2521-2530
Non-thermal technologies can maintain fruit and vegetable products quality better than traditional thermal processing. Pulsed light (PL) is a non-thermal method for microbial inactivation (vegetative cells and spores) in fruits and vegetables. The PL treatment involves the application of intense and short-duration pulses of broad spectrum wavelengths ranging from UV to near-infrared (100–1100 nm). This review summarized application of PL technology to control microbial contamination and increasing shelf-life of some fruits and vegetables including apple, blueberries, grape, orange, strawberries, carrot, lettuce, spinach, and tomato. The microbial inactivation in very short treatment times, low energy used by this system, flexibility for solid or liquid samples, few residual compounds and no synthetic chemicals that cause environmental pollution or harm humans, is benefits of PL technique. The efficiency of PL disinfection is closely associated with the input voltage, fluence (energy dose), composition of the emitted light spectrum, number of lamps, the distance between samples and light source, and frequency and number of applied pulses. The PL treatments control pathogenic and spoilage microorganisms, so it facilitates the growth and development of the starter microorganisms affecting product quality. 相似文献
95.
So far, mass spectrometry-based targeted proteomics is the most sensitive approach to answer and address specific biological questions in an accurate and quantitative fashion. However, the data analysis design used for such quantification varies in the field leading to discrepancies in the reported values. In this study, different quantification strategies based on calibration curves were evaluated and compared. The best accuracy and coefficient of variation was achieved by ratio to ratio calibration curves. We applied the ratio to ratio quantification approach to analyze very low abundant insulin signaling proteins such as PIK3RA (0.10–0.93 fmol/μg), AKT1 (0.1–0.39 fmol/μg), and the insulin receptor (0.22–2.62 fmol/μg) in a fat cell model and demonstrated the adaptation of this pathway at different states of insulin sensitivity. 相似文献
96.
20世纪以来,干细胞与再生医学技术一直是国际生物医学领域的热点前沿之一,它为保障人类生命健康、改善人类生存质量和延长人类寿命发挥不可替代的巨大作用。因此,美国、欧洲国家、日本和中国等科技大国均将该领域纳入了国家科研与产业发展的重点战略中,并通过专项扶持、政策补贴、立法保障等方式激励该领域的创新发展。通过对近年来国际科技战略和科技研发态势的梳理分析,发现该领域的国际战略布局规律,揭示我国在该领域的领先优势与弱点,为我国未来干细胞与再生医学技术发展提出相关参考建议。 相似文献
97.
Haijing Bai Jianlin Guo Cuifang Chang Xueqiang Guo Cunshuan Xu Wei Jin 《Journal of cellular physiology》2019,234(10):18897-18905
This study aims to reveal the regulatory mechanism of lncRNAs–miRNAs–mRNAs network during the proliferative phase of liver regeneration (LR). High-throughput sequencing technology was performed, and a total of 1,738 differentially expressed lncRNAs (DE lncRNAs), 167 known differentially expressed miRNAs (DE miRNAs), and 2,727 differentially expressed mRNAs were identified. Then, the target DE lncRNAs and DE mRNAs regulated by the same miRNAs were screened and a ceRNA regulatory network containing 32 miRNAs, 107 lncRNAs, and 270 mRNAs was constructed. Insulin signaling pathway, pyrimidine metabolism, axon guidance, carbohydrate digestion and absorption, and pyruvate metabolism were significantly enriched in the network. Through literature review and the regulatory relationship between lncRNAs and miRNAs, nine core lncRNAs were identified, which might play important roles during the proliferative phase of rat LR. This study analyzed lncRNA–miRNA–mRNA regulatory network for the first time during the proliferative phase of rat LR, providing clues for exploring the mechanism of LR and the treatment of liver diseases. 相似文献
98.
《L'Anthropologie》2019,123(2):276-288
Previously the single bifacial tools found in different industrial variants of the Altai Middle Paleolithic (Sibiryachikha and Kara-bom) were not considered to be cultural markers that could be used to differentiate the technological/cultural variants, but rather a bright, but situational manifestation of the typological variability, especially in the case of the Sibiryachika assemblages. As a result of recent studies of Chagyrskaya Cave, the key-site of Sibiryachikha, it was found that all the bifaces are made using plano-convex technology. In the Chagyrskaya Cave assemblage all stages of bifacial production have been found: pre-forms, bifacial tools and tools made on the bifacial thinning flakes, accompanied by numerous bifacial thinning flakes and bifacial thinning chips. A preliminary study of the bifaces from the second Sibiryachikha site, Okladnikov Cave evidenced the use of the same plano-convex technology. On the other hand, in the Kara-bom complexes (Kara-Bom, Ust-Karakol-1, Anuy-3), all bifacial tools are made using bi-convex bifacial technology. Thus, the criteria for the technological distinction of bifacial production assume special importance as a cultural marker that allows the differentiation the Altai Middle Paleolithic technological variants. Taking into account the fact that Chagyrskaya Cave and Okladnikov Cave are associated only with Neanderthal remains, it can be assumed that bifacial plano-convexe technology in the Middle Paleolithic of Altai is linked to the appearance and existence of their population in the region. 相似文献
99.
The spatial extent of animal movement is a key consideration when designing conservation measures, such as marine protected areas. Methods to assess territory size in the marine environment, however, are labour intensive and/or expensive. Here, we explore a novel method to investigate the spatial ecology of territorial fishes by examining their reactions to an artificial light stimulus. During benthic towed video surveys conducted in Lyme Bay, southwest England, several species of wrasse (Labridae) have frequently been observed pursuing a laser projected onto the seabed. While the motivation behind ‘laser‐chasing’ is unclear, we quantified the spatial aspects of this behaviour by comparing chase distance and chase likelihood between and within species, to determine the potential utility of this method for investigating space use and aggression in wild fishes. Cuckoo wrasse (Labrus mixtus) were significantly more likely to display agonistic behaviour towards the laser than Goldsinny wrasse (Ctenolabrus rupestris). Goldsinny wrasse displayed a positive relationship between total length and chase‐distance, but not Cuckoo wrasse. The observed species differences may relate to behavioural factors affecting the motivation behind ‘laser‐chasing’, which is discussed. Chases by the cuckoo wrasse were significantly longer than those by Goldsinny wrasse, and these chase distances were used to estimate theoretical territory sizes for each species. To our knowledge, this is the first study to explore the spatial aspects of the reactions to an artificial stimulus by wild fishes. The potential to develop the method to directly investigate aspects of territoriality and aggression in wild fishes is discussed, including necessary further refinements and testing. Wild wrasses are increasingly exploited in Europe to provide cleaner fish for salmonid aquaculture, and we encourage the development of methods to inform spatial conservation measures for these ubiquitous and iconic species. 相似文献
100.
Usha R. Dutta Sudha N. Rao Vijaya Kumar Pidugu Vineeth V.S. Amrita Bhattacherjee Aneek Das Bhowmik Sathish K. Ramaswamy Kumar Gautam Singh Ashwin Dalal 《Genomics》2019,111(5):1108-1114
Disease associated chromosomal rearrangements often have break points located within disease causing genes or in their vicinity. The purpose of this study is to characterize a balanced reciprocal translocation in a girl with intellectual disability and seizures by positional cloning and whole genome sequencing. The translocation was identification by G- banding and confirmed by WCP FISH. Fine mapping using BAC clones and whole genome sequencing using Oxford nanopore long read sequencing technology for a 1.46 X coverage of the genome was done. The positional cloning showed split signals with BAC RP11-943 J20. Long read sequencing analysis of chimeric reads carrying parts of chromosomes X and 20 helped to identify the breakpoints to be in intron 2 of ARHGEF9 gene on Xp11.1 and on 20p13 between RASSF2 and SLC23A2 genes. This is the first report of translocation which successfully delineated to single base resolution using Nanopore sequencing. The genotype-phenotype correlation is discussed. 相似文献