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351.
Growth,body composition and digestive enzyme responses of Caspian Kutum,Rutilus frisii (Kamenskii, 1901), juveniles fed different levels of carbohydrates 下载免费PDF全文
S. Mohammadzadeh H. A. Noverian H. Ouraji B. Falahatkar 《Zeitschrift fur angewandte Ichthyologie》2017,33(5):983-990
The study evaluated the effects of dietary carbohydrate levels on growth performance and digestive enzyme activities in juveniles Caspian Kutum, Rutilus frisii (Kamenskii, 1901). Fish with an initial average weight of 0.8 ± 0.2 g (means ± SD) were fed five isonitrogenous and isoenergic formulated diets with different carbohydrate levels of 15%, 20%, 25%, 30% and 35% in triplicate groups for 10 weeks (fifteen 45‐L aquaria with 30 fish per tank and water temperature of 21.5–23.5°C). Based on the results, growth performance of Caspian Kutum was significantly improved by increasing carbohydrate levels from 15% to 35% (p < .05). A result of body composition analysis showed that the protein content was elevated with increasing carbohydrate levels (p < .05). Digestive enzyme activities were significantly influenced by dietary carbohydrate levels (p < .05). Trypsin, chymotrypsin, lipase and amylase specific activities increased significantly with rising carbohydrate levels from 15% to 35%. Alkaline phosphatase and N amino peptidase activities increased with carbohydrate levels increasing from 15% to 25%, but decreased with a further rise in the carbohydrate level from 25% to 35%. The results indicate that increasing carbohydrate levels from 15% to 35% have positive effects on growth parameters. However, carbohydrate amounts at levels higher than 35% and their effects on growth performance and digestive enzymes are not obvious, hence, more widespread studies on this nutrient are recommended. 相似文献
352.
Omeed Moaven Hamid Reza Raziee Hamid Reza Sima Azita Ganji Reza Malekzadeh Azadeh A’rabi Abbas Abdollahi Bahram Memar Masoud Sotoudeh Hossein Naseh Navid Nekoui Adeleh Razavipour Mehran Gholamin Ezzat Dadkhah Moein Farshchian Mohammad Reza Abbaszadegan 《Cancer epidemiology》2010,34(3):285-290
Background: A complex of genetic and environmental factors is involved in carcinogenesis of the esophageal squamous cell carcinoma (ESCC). Glutathione-S-Transferases (GSTs) are phase-II enzymes playing role in detoxification of carcinogen electrophiles. Genetic polymorphisms of GSTM1, GSTT1 and GSTP1 in association with some environmental factors and their impact on esophageal cancer susceptibility were assessed in the Iranian population. Methods: Genomic DNA of peripheral blood leukocytes from 148 confirmed esophageal cancer cases and 137 healthy individuals as control group was assayed for restriction fragment length polymorphisms in the GSTP1 loci by PCR amplification followed by digestion with Alw26I. Deletion of the GSTM1 and GSTT1 genes was detected by multiplex PCR. A data-mining method based on decision trees was applied to produce a predictive model of interactions between genotypes. Results: Smoking was independently associated with ESCC (p < 0.05, OR: 2.286, 95% CI = 1.311–3.983). Smoking along with GSTP1 Val/Val genotype was associated to ESCC (p < 0.001, OR: 3.886, 95% CI = 1.830–8.251), while non-smokers with GSTP1 Val/Val were significantly more frequent in non-cancerous group. (p = 0.007, OR: 0.507, 95% CI = 0.309–0.830). Conclusions: Data-mining methods are useful tools to map out a scheme for predicting complex relations and combinations of different genotypes. Genotyping analysis of GSTP1 together with assessment of smoking seems to be important in determining the risk of ESCC in the Iranian population. 相似文献
353.
Shirin Hooshmand Anju Balakrishnan Richard M. Clark Kevin Q. Owen Sung I. Koo Bahram H. Arjmandi 《Phytomedicine》2008,15(8):595-601
Postmenopausal bone loss is a major public health concern. Although drug therapies are available, women are interested in alternative/adjunct therapies to slow down the bone loss associated with ovarian hormone deficiency. The purpose of this study was to determine whether dietary supplementation of l-carnitine can influence bone density and slow the rate of bone turnover in an aging ovariectomized rat model. Eighteen-month-old Fisher-344 female rats were ovariectomized and assigned to two groups: (1) a control group in which rats were fed ad libitum a carnitine-free (−CN) diet (AIN-93M) and (2) another fed the same diet but supplemented with l-carnitine (+CN). At the end of 8 weeks of feeding, animals were sacrificed and bone specimens were collected for measuring bone mineral content (BMC) and density (BMD) using dual energy X-ray absorptiometry. Femoral microarchitectural properties were assessed by microcomputed tomography. Femoral mRNA levels of selected bone matrix proteins were determined by northern blot analysis. Data showed that tibial BMD was significantly higher in the rat fed the +CN diet than those fed the −CN (control) diet. Dietary carnitine significantly decreased the mRNA level of tartrate-resistant acid phosphatase (TRAP), an indicator of bone resorption by 72.8%, and decreased the mRNA abundance of alkaline phosphatase (ALP) and collagen type-1 (COL), measures of bone formation by 63.6% and 61.2%, respectively. The findings suggest that carnitine supplementation slows bone loss and improves bone microstructural properties by decreasing bone turnover. 相似文献
354.
Zarghi A Najafnia L Daraee B Dadrass OG Hedayati M 《Bioorganic & medicinal chemistry letters》2007,17(20):5634-5637
A group of 2,3-diaryl-1,3-thiazolidine-4-ones, possessing a methylsulfonyl pharmacophore, were synthesized and their biological activities were evaluated for cyclooxygenase-2 (COX-2) inhibitory activity. 相似文献
355.
Six species of terrestrial isopods from the province of Qazvin, central Iran, are recorded. Three species, Hemilepistus
klugii (Brandt, 1833), Protracheoniscus
ehsani Kashani, 2014 and Mongoloniscus
persicus Kashani, 2014, were previously reported from the province. Hemilepistus
elongatus Budde-Lund, 1885 and Protracheoniscus
major (Dollfus, 1903) are recorded for the first time, and one species, Protracheoniscus
sarii
sp. n., is described as new. The diagnostic characters of the new species are figured. 相似文献
356.
Isolation and identification of chemotherapy‐enriched sphere‐forming cells from a patient with gastric cancer 下载免费PDF全文
357.
The Duong Huyen Pham Teng Choon Kho Pheng Phang Kean Chern Fong Di Yan Yanting Yin Jun Peng Md Arafat Mahmud Saba Gharibzadeh Bahram Abdollahi Nejand Ihteaz M. Hossain Motiur Rahman Khan Naeimeh Mozaffari YiLiang Wu Heping Shen Jianghui Zheng Haoxin Mai Wensheng Liang Chris Samundsett Matthew Stocks Keith McIntosh Gunther G. Andersson Uli Lemmer Bryce S. Richards Ulrich W. Paetzold Anita Ho‐Ballie Yun Liu Daniel Macdonald Andrew Blakers Jennifer Wong‐Leung Thomas White Klaus Weber Kylie Catchpole 《Liver Transplantation》2020,10(9)
Mixed‐dimensional perovskite solar cells combining 3D and 2D perovskites have recently attracted wide interest owing to improved device efficiency and stability. Yet, it remains unclear which method of combining 3D and 2D perovskites works best to obtain a mixed‐dimensional system with the advantages of both types. To address this, different strategies of combining 2D perovskites with a 3D perovskite are investigated, namely surface coating and bulk incorporation. It is found that through surface coating with different aliphatic alkylammonium bulky cations, a Ruddlesden–Popper “quasi‐2D” perovskite phase is formed on the surface of the 3D perovskite that passivates the surface defects and significantly improves the device performance. In contrast, incorporating those bulky cations into the bulk induces the formation of the pure 2D perovskite phase throughout the bulk of the 3D perovskite, which negatively affects the crystallinity and electronic structure of the 3D perovskite framework and reduces the device performance. Using the surface‐coating strategy with n‐butylammonium bromide to fabricate semitransparent perovskite cells and combining with silicon cells in four‐terminal tandem configuration, 27.7% tandem efficiency with interdigitated back contact silicon bottom cells (size‐unmatched) and 26.2% with passivated emitter with rear locally diffused silicon bottom cells is achieved in a 1 cm2 size‐matched tandem. 相似文献
358.
359.
Javad Gharechahi Mohammad Farhad Vahidi Mohammad Bahram Jian-Lin Han Xue-Zhi Ding Ghasem Hosseini Salekdeh 《The ISME journal》2021,15(4):1108
Rumen microbiota play a key role in the digestion and utilization of plant materials by the ruminant species, which have important implications for greenhouse gas emission. Yet, little is known about the key taxa and potential gene functions involved in the digestion process. Here, we performed a genome-centric analysis of rumen microbiota attached to six different lignocellulosic biomasses in rumen-fistulated cattle. Our metagenome sequencing provided novel genomic insights into functional potential of 523 uncultured bacteria and 15 mostly uncultured archaea in the rumen. The assembled genomes belonged mainly to Bacteroidota, Firmicutes, Verrucomicrobiota, and Fibrobacterota and were enriched for genes related to the degradation of lignocellulosic polymers and the fermentation of degraded products into short chain volatile fatty acids. We also found a shift from copiotrophic to oligotrophic taxa during the course of rumen fermentation, potentially important for the digestion of recalcitrant lignocellulosic substrates in the physiochemically complex and varying environment of the rumen. Differential colonization of forages (the incubated lignocellulosic materials) by rumen microbiota suggests that taxonomic and metabolic diversification is an evolutionary adaptation to diverse lignocellulosic substrates constituting a major component of the cattle’s diet. Our data also provide novel insights into the key role of unique microbial diversity and associated gene functions in the degradation of recalcitrant lignocellulosic materials in the rumen.Subject terms: Bacterial genetics, Metagenomics 相似文献
360.
Comparative life history and fecundity of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) on different soybean varieties 总被引:1,自引:0,他引:1
Bahram NASERI Yaghoub FATHIPOUR Saeid MOHARRAMIPOUR Vahid HOSSEININAVEH 《Entomological Science》2009,12(2):147-154
The effect of different soybean varieties ( Glycine max 356, M4, M7, M9, Clark, Sahar, JK, BP, Williams, L17, Zane, Gorgan3 and DPX) on the life history and fecundity of the gram pod borer Helicoverpa armigera (Hubner) (synonym Heliothis armigera (Hubner), also known as the American or African bollworm) was determined at 25 ± 1°C, 65 ± 5% r.h. and a light : dark cycle of 16:8 h. The larval period ranged 17.30 to 26.20 days on M7 and L17, respectively. The longest development time was on L17, BP and Sahar (42.71, 40.29 and 39.20 days, respectively) and the shortest was on M7, M9, Williams and Clark (34.21, 36.06, 36.60 and 36.82 days, respectively). The development index of overall immature stages varied from 1.39 to 2.41, with the minimum on L17 and BP and the maximum on M7. The highest daily fecundity and total fecundity (118.92 and 582.70 eggs, respectively) and the lowest (37.88 and 177.10 eggs, respectively) were observed on DPX and 356, respectively. Cluster analysis of the biological parameters of H. armigera on different soybean varieties demonstrated that BP, Sahar and L17 were partially resistant to H. armigera . Knowledge of the extent of susceptibility or resistance of crop varieties and biology of a pest on that crop are fundamental components of integrated pest management (IPM) programs for many crops. Such information can help to detect and monitor pest infestation, variety selection and crop breeding. 相似文献