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排序方式: 共有202条查询结果,搜索用时 31 毫秒
81.
Protein digestibility and quality of six enteral nutrition products sold in Canada were studied by rat balance and growth methods. Casein+L-methionine, 0.2 g/100 g diet (control) and six enteral products (freeze-dried) were fed as the sole source of protein in diets containing 8.61-9.12 g/100 g protein (N x 6.25) to weanling and 18-mo-old rats for a period of 2 and 1 wk, respectively. A protein-free diet was also included in the feeding studies to permit calculations of true protein digestibility and net protein ratio values. Values for true digestibility of protein as determined in old rats for the control diet and the test products were 95 and 89-93%, respectively. Compared with old rats, protein digestibility values were 5-7 percentage units higher in young rats. The 2-wk relative protein efficiency ratio values (42-56%) or the relative net protein ratio values (61-74%) of the enteral products were considerably lower compared to those of the control (100). Supplementation of an enteral product with cysteine, cysteine + tryptophan, cysteine + threonine or cysteine + tryptophan + threonine caused significant improvement in protein quality; suggesting that the product was limiting in these three amino acids. The protein digestibility-corrected amino acid scores for the enteral products were 43-46, 69-75 and 86-93% by using whole egg, casein and the FAO-WHO (1991) pattern as reference proteins, respectively. The results indicate that these enteral products are inferior to casein in protein quality. 相似文献
82.
Farheen Gul Khafsa Malik Rahmatullah Qureshi Mushtaq Ahmad Lubna Ansari Muhammad Zafar Sabtain Hussain Sidra Khalid Muhammad Imran Neelam Rashid 《Microscopy research and technique》2022,85(4):1392-1409
The current study aimed to investigate the palyno-morphological features of Asteraceous species from District Dera Ismail Khan, Khyber Pakhtunkhwa, Pakistan. A total of 13 species were collected, pressed, identified, and examined by using light and scanning electron microscopy. Both qualitative and quantitative pollen characters were observed, that is, equatorial and polar diameter, number of pores and colpi, exine thickness, exine sculpturing, pollen shape, and P/E ratio. Pollen shapes observed in studied taxa were spheroidal, suboblate, oblate-spheroidal, and lophate-spheroidal. The aperturation patterns of pollens vary from tricolporate to tetracolporate. The maximum polar and equatorial diameter of 75–100 (87.5 ± 13.6) μm and 87.5–117.5 (102.5 ± 16.4) μm, respectively, was recorded in Echinops echinatus, while minimum polar and equatorial diameter of 20–22.5 (21 ± 1.36) μm and 22.5–25 (23.5 ± 1.36) μm, respectively, was recorded in Aster subulatus. Six types of exine sculpturing patterns were observed; echinate, micro-echinate, echinate-microreticulate, microreticulate, echinate-perforate, and scabrate. Maximum exine thickness of 8.75 μm was recorded in E. echinatus and minimum of 1.25 μm in Launaea mucronata. The pollen morphology has valuable significance in understanding the taxonomy of different plant groups and plays a central role in the correct identification and classification of Asteraceous flora at species, generic, and tribe levels. 相似文献
83.
Jezabel Praz Laure Gune Sarwar Aziz Albrecht Berkessel Alexandre Alexakis 《Advanced Synthesis \u0026amp; Catalysis》2012,354(9):1780-1790
Novel endo,endo‐2,5‐diaminonorbonane‐derived tertiary C2‐symmetrical diamines were synthesized via the one‐pot reductive amination of enantiomerically pure norbornane‐2,5‐dione. These ligands were applied to various catalytic reactions such as asymmetric deprotonation, asymmetric bromine‐lithium exchange, and enantioselective addition of aryl‐ and allkylithium reagents to aromatic aldimines. 相似文献
84.
Lubna Ahmed Ana Belen Martin-Diana Daniel Rico Catherine Barry-Ryan 《Food and Bioprocess Technology》2012,5(8):3103-3114
The aim of this study was to examine the applicability of delactosed whey permeate (DWP) treatment on preserving the quality and antioxidant attributes of fresh-cut tomato. Tomatoes were treated with 3% DWP by dipping, spraying and a combination of both, stored at 4?°C for 10?days and compared with the industrial standard, chlorine. The combination of dipping and spraying of DWP showed the best results for all the markers tested. The combined treatment of dipping and spraying of DWP significantly lowered total counts (??1.0 log cfu/g), yeast and moulds (??1.2 log cfu/g), inhibited the loss of firmness (25%) and reduced POD activity (15%) of the tomato slices after 10?days compared to the chlorine treatment. Moreover, DWP-treated tomatoes maintained significantly (p?<?0.05) higher levels of vitamin C, total phenols and antioxidant activity (DPPH) than the chlorine-treated samples during storage. Sensory scores confirmed that DWP-treated tomatoes retained better aroma and texture. Also, the appearance and overall acceptability were higher than chlorine-treated tomatoes. Thus DWP treatment has potential to extend the shelf life of fresh-cut tomatoes. 相似文献
85.
Ayesha Kausar Sonia Zulfiqar Zahoor Ahmad Muhammad Ishaq Muhammad Ilyas Sarwar 《应用聚合物科学杂志》2012,124(1):373-385
A series of novel aromatic and aromatic–aliphatic diamines [isophthaloyl bis(3‐(3‐aminophenyl)thiourea), terephthaloyl bis(3‐(3‐aminophenyl)thiourea), adipoyl bis(3‐(3‐aminophenyl)thiourea), sebacoyl bis(3‐(3‐aminophenyl)thiourea)] were synthesized starting from the dinitro compounds. Spectroscopic and elemental analyses were carried out for the structure elucidation of the monomers. Three series of poly(thiourea‐amide)s (PTAMs) bearing C?S groups were prepared through the condensation of new diamines with the diacid chlorides such as isophthaloyl, terephthaloyl and adipoyl chloride. The ensuing PTAMs were characterized using FTIR, 1H‐NMR and 13C‐NMR techniques. Physical properties of the polymers such as solution miscibility, crystallinity, solution viscosity, molecular weight, and thermal properties were measured. Consequently, good organosolubility of these polymers was experiential in amide solvents as DMAc, DMF, DMSO and NMP. Moreover, PTAMs exhibited ηinh in the range of 0.92–1.56 dL/g and GPC measurements revealed Mw around 607 × 102‐851 × 102. DSC served to envisage the glass transition temperatures (Tg) of poly(thiourea‐amide)s located between 232 and 258°C and the initial decomposition temperatures (T0) probed by thermogravimetry were in the range of 305–419°C. Structure‐property relationship of these polymers was also studied. Eventually, solid?liquid extraction tests of the selected poly(thiourea‐amide)s systems revealed excellent results because these polymers show nearly 100% elimination of lead and mercury cations from water media. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
86.
Abstract Nalita (Trema orientalis) is one of the fastest growing trees in the tropical countries. The structural characteristics of lignin isolated at different ages of Nalita wood (Trema orientalis) by acidolytic dioxane method were examined by UV, FTIR, 1H‐NMR and 13C‐NMR spectroscopy, alkaline nitrobenzene oxidation, molecular weight determination, elemental and methoxyl analysis. The data were compared with aspen lignin. The structural analysis revealed that Nalita wood lignin is syringyl‐guaiacyl type. The methoxyl content in Nalita wood lignin was lower than aspen lignin. The C9 formulas for 30‐months‐old Nalita was C9H9.31O3.13(OCH3)1.27, whereas that of aspen was C9H8.94O3.15(OCH3)1.47. The weight average molecular weight of Nalita wood lignin was decreased from 36,500 to 25,500 with increasing tree age from 12 to 30 months, whereas weight average molecular weight of aspen was 20,000. Both alcoholic and phenolic hydroxyl group in Nalita wood lignin is lower than aspen lignin. 相似文献
87.
88.
89.
Souvik Ghatak Syrina F. Mehrabi Lubna M. Mehdawi Shakti Ranjan Satapathy Anita Sjlander 《International journal of molecular sciences》2022,23(2)
Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality worldwide. The current TNM (Tumor, Node, and Metastasis) classification approach is suboptimal in determining the prognosis of CRC patients. The prognosis for CRC is affected by a variety of features that are present at the initial diagnosis. Herein, we performed a systematic exploration and established a novel five-panel gene signature as a prognostic and early diagnosis biomarker after performing differential gene expression analyses in five independent in silico CRCs cohort and independently validating it in one clinical cohort, using immunohistochemistry. Four genes (BDNF, PTGS2, GSK3B, and CTNNB1) were significantly upregulated and one gene (HPGD) was significantly downregulated in primary tumor tissues compared with adjacent normal tissues throughout all the five in silico datasets. The univariate CoxPH analysis yielded a five-gene signature that accurately predicted overall survival (OS) and recurrence-free survival (RFS) in the in silico training (AUC = 0.73 and 0.69, respectively) and one independent in silico validation cohort (AUC = 0.69 and 0.74, respectively). This five-gene signature demonstrated significant associations with poor OS in independent clinical validation cohorts of colon cancer (CC) patients (AUC = 0.82). Intriguingly, a risk stratification model comprising of the five-gene signature together with TNM stage and gender status achieved an even superior AUC of 0.89 in the clinical cohorts. On the other hand, the circulating mRNA expression of the upregulated four-gene signature achieved a robust AUC = 0.83 with high sensitivity and specificity as a diagnosis marker in plasma from CRC patients. We have identified a novel, five-gene signature as an independent predictor of OS, which in combination with TNM stage and gender offers an easy-to-translate and facile assay for the personalized risk-assessment in CRC patients. 相似文献
90.
Ewa A. Burian Lubna Sabah Tonny Karlsmark Klaus Kirketerp-Mller Christine J. Moffatt Jacob P. Thyssen Magnus S. gren 《International journal of molecular sciences》2022,23(12)
Venous leg ulcers (VLUs) are the most common type of leg ulcers with a significant socioeconomic burden due to slow healing. Cytokines may be involved in the pathogenesis of VLUs. In this systematic review, our objective was to investigate the association between cytokine levels, including growth factors, with the healing of VLUs. PubMed, Embase, Web of Science and Cochrane Library were searched from their inception to August 2021. We retrieved 28 articles investigating 38 different cytokines in 790 patients. Cytokines were most commonly investigated in wound fluid and less frequently in biopsies and serum. The studies were judged as having a moderate to high risk of bias, and the results were often inconsistent and sometimes conflicting. A meta-analysis was not performed due to clinical and methodological heterogeneities. We found weak evidence for elevated IL-1α, IL-6, IL-8, TNF-α and VEGF levels in non-healing VLUs, an elevation that declined with healing. TGF-β1 levels tended to increase with VLU healing. Other cytokines warranting further investigations include EGF, FGF-2, GM-CSF, IL-1β, IL-1Ra and PDGF-AA/PDGF-BB. We conclude that non-healing VLUs may be associated with an elevation of a palette of pro-inflammatory cytokines, possibly reflecting activated innate immunity in these wounds. There is a paucity of reliable longitudinal studies monitoring the dynamic changes in cytokine levels during wound healing. 相似文献