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排序方式: 共有214条查询结果,搜索用时 15 毫秒
111.
This paper reports on model studies on energy dissipatorswhich were performed with a view towards developing a shorterand more efficient type of stilling basin for circular pipeoutlets at low Froude numbers. The stilling basin models weretested for two pipe outlet diameters. The outlet Froude numberfor testing ranged from 1.70 to 5.50. The studies reported inthis paper expand on the improvement suggested by Goel andVerma (1999). In all, 133 test runs were made on 19 newmodels. Various configurations of stilling basin models withdifferent sizes, shapes and locations of appurtenances andbasin lengths were tested. The use of a wedge-shaped splitterblock, an impact wall, and the use of wedge-shaped blocks asbaffle blocks resulted in efficient energy dissipation inshorter lengths of stilling basin. A non-dimensional numbertermed as scour index has been used to compare theperformances of various stilling basin models. It was foundthat the length of stilling basin could be reducedconsiderably without affecting the performance by choosing asuitable configuration of the stilling basin. Of theconfigurations tested, the stilling basin model M-24 with tworows of wedge-shaped baffle blocks in a basin length of sixtimes the diameter of pipe outlet (6d) performed better incomparison to USBR impact type VI stilling basin. 相似文献
112.
Saikat P. Biswas Arun G. Jadhao Nikhil V. Palande 《Fish physiology and biochemistry》2014,40(2):457-467
We are reporting for the first time that the catecholamines (adrenaline and noradrenaline) inhibit the effect of nitric oxide (NO) on melanosome dispersion in freshly isolated scales of the freshwater snakehead fish, Channa punctatus. We studied the effect of NO and catecholamines on the pigment displacement by observing the changes in the melanophore index. The scales when treated with solution containing NO donor sodium nitroprusside (SNP) showed dispersion of melanosomes, whereas NO synthase blocker N-omega-Nitro-l-arginine suppresses this action of SNP. Treatment with adrenaline and noradrenaline on the isolated scales caused aggregation of melanosomes. Scales treated with solution containing catecholamines and SNP resulted in aggregation of melanosomes suggesting that catecholamines mask the effect of SNP. These results suggest that the catecholamines are inhibiting the effect of NO and causing the aggregation of the melanosomes may be via surface receptors. 相似文献
113.
Arun A.B. Sridhar K.R. Raviraja N.S. Schmidt E. Jung K. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2003,58(3):1-13
Seeds of two coastal sand dune wild legumes, Canavalia cathartica and Canavalia maritima from the west coast of India were analyzed for their nutritional and antinutritional properties. The seeds contained 35.5 and 34.1% crude protein, 52.8 and 50.5% crude carbohydrates, 1.3 and 1.7% crude lipids and 3.1 and 3.5% ash content, respectively. Among the minerals, potassium was the highest followed by phosphorus. Globulins and albumins constituted the major seed proteins of both plants. Most of the essential amino acids were at adequate levels. Although the crude lipids were below 2%, the unsaturated fatty acids were high. Seeds did not contain tannins and trypsin inhibitors. The levels of total phenolics were low, but showed high hemagglutination activity. The nutritional properties of these seeds have been compared with other Canavalia spp. and wild unconventional or tribal legumes. Overall, the study results suggest that the seeds of C. cathartica and C. maritima possess potential nutritive value particularly higher protein, essential amino acids and low levels of antinutritional factors. These wild legumes are adapted to low nutrient, high saline and drought conditions of the coastal sand dunes; their conservation and domestication are warranted as potential alternative sources of protein. 相似文献
114.
ABSTRACTA 30-day experiment was conducted to assess the effect of tryptophan-supplemented diets on growth and survival of Pabda, Ompok bimaculatus fry. Fifty pabda fry (0.114 ± 0.02 g; 2.45 ± 0.13 cm) were stocked into each aerated aquarium following a completely randomized design consisting of four treatments with triplicate each. Four iso-proteinious purified diets were prepared with different levels of tryptophan—0%, 1%, 2%, and 3%—of the dry diet and were designated as Control, TRP1, TRP2, and TRP3 respectively. Fishes were fed with the experimental diet ad libitum four times a day. The results showed that fish fed with tryptophan-supplemented diets exhibited significantly (P < 0.05) lower cannibalism and higher survival than the control diet. Further, the tryptophan-supplemented groups showed a significantly lower coefficient of variation (%) and size heterogeneity (P < 0.05). However, the growth as measured by body weight gain, length increment, and specific growth rate of fry in tryptophan-supplemented groups was significantly lower than the control group (P < 0.05). Moreover, maximum survival (52.67 ± 1.76%) and minimum cannibalism (21.33 ± 5.70%) coupled with higher growth and performance index (0.38 ± 0.01) were recorded in the 2% tryptophan-supplemented group compared to other tryptophan-fed groups. Overall interpretation from the present study concludes that the dietary supplementation of 2% tryptophan is recommended for better survival of pabda fish, although growth was compromised. 相似文献
115.
Rozenn Jossé Yong-Wei Zhang Valentin Giroux Arun K. Ghosh Ji Luo Yves Pommier 《Marine drugs》2015,13(6):3625-3639
Lasonolide A (LSA), a potent antitumor polyketide from the marine sponge, Forcepia sp., induces rapid and reversible protein hyperphosphorylation and premature chromosome condensation (PCC) at nanomolar concentrations independent of cyclin-dependent kinases. To identify cellular targets of LSA, we screened 2951 shRNAs targeting a pool of human kinases and phosphatases (1140 RefSeqs) to identify genes that modulate PCC in response to LSA. This led to the identification of RAF1 (C-RAF) as a mediator of LSA-induced PCC, as shRNAs against RAF1 conferred resistance to LSA. We found that LSA induced RAF1 phosphorylation on Serine 338 within minutes in human colorectal carcinoma HCT-116, ovarian carcinoma OVCAR-8, and Burkitt’s lymphoma CA46 cell lines. RAF1 depletion by siRNAs attenuated LSA-induced PCC in HCT-116 and OVCAR-8 cells. Furthermore, mouse embryonic fibroblasts (MEF) with homozygous deletion in Raf1, but not deletion in the related kinase Braf, were resistant to LSA-induced PCC. Complementation of Raf1−/− MEFs with wild-type human RAF1, but not with kinase-dead RAF1 mutant, restored LSA-induced PCC. Finally, the Raf inhibitor sorafenib, but not the MEK inhibitor AZD6244, effectively suppressed LSA-induced PCC. Our findings implicate a previously unknown, MAPK-independent role of RAF1 in chromatin condensation and potent activation of this pathway by LSA. 相似文献
116.
Punit Kumar Khanna Ratna Chandra Arun Kumar Nidhi Dogra Heena Gupta Gourav Gupta Vijeshwar Verma 《Journal of Crop Science and Biotechnology》2014,17(1):27-34
Genetic diversity among 14 Withania accessions were studied using morphological, chemical, and RAPD (Rapid Amplification of Polymorphic DNA) markers. On the basis of morphological variation and maximum assimilation of chemical constituents, wild accessions were considered elite as compared to cultivated. The molecular study showed that a total of 12 DNA fragments were amplified with five random decamer primers 75% of which were polymorphic. Genetic similarity matrix based on the Dice index detected coefficients ranging from 0.556 to 0.941. These coefficients were used to construct a dendrogram using unweighted pair group method with arithmetic mean (UPGMA). These accessions were clustered into two major groups; the first group included AGB-009, AGB-012, AGB-042, AGB-030, AGB-053, AGB-019, AGB-017, AGB-002, and AGB-003; the second included AGB-025, AGB-001, AGB-036, AGB-015, and AGB-055. The highest similarity among the Ashwagandha accessions was observed between AGB-009 and AGB-030, AGB-009 and AGB-012, AGB-042 and AGB-030, AGB-025 and AGB-001, AGB-036 and AGB-015, AGB-015 and AGB-055 and between AGB-015 and AGB-055. The most distant populations in the dendrogram were AGB-053 and AGB-055. The combination of morphological, chemical, and molecular markers assessment will be useful in studying the genetic diversity of Withania for identification, conservation, breeding, improvement activities, and in order to achieve elite type in terms of bioactive metabolites. 相似文献
117.
Shashi K. Mahajan Arun Anand Vandana Sangwan Jitender Mohindroo Kiranjit Singh 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(4):399-401
This is the first report of a metallic foreign body in the spleen of a dog. The animal had abdominal discomfort with a tucked-up abdomen and occasional vomition. Radiography and ultrasonography were used to identify a splenic foreign body which was surgically removed through a ventral midline celiotomy. Migration of the foreign body through the stomach wall was suspected as the most likely cause. 相似文献
118.
Semecarpus kurzii Engl.is an important ethnomedicinal plant used for curing tumours,inflammation,fever and pain,and is also a source of iso ricinoleic acid.During the present investigation,effect of chemical pretreatments on germination and seedling growth revealed significant differences.Different pre-treatments could improve germination and treatment with KNO_3 (9.9 mM)was significantly superior(94%) to the untreated control(76%).Mean daily germination varied among the treatments(0.90–4.14 seeds per day),when compared with 2.27 seeds per day in control.Mean germination time was significantly reduced from 22.14 days(control) to 16.40 days(19.8 mM KNO_3) and 17.16 days(1.45 mM GA_3).Treatment with KNO_3(19.8 mM) and GA_3(1.45 and 2.90 mM)significantly reduced the time for 50% germination.Treatment with higher concentrations of GA_3 and KNO_3 exhibited significantly faster germination initiation(11.0 and 12.0 days,respectively) over the control(17.0 days).Seedling vigour index was not improved by pre-treatments.Chemical treatments did not improve shoot growth,collar thickness,or number of seedling leaves; however,root growth was significantly improved over control.Treatment with GA_3(2.90 mM) promoted leaf elongation but reduced leaf width significantly.Treatment with KNO_3 and GA_3 could be recommended to obtain healthy seedlings for establishing new plantations of this important medicinal plant species. 相似文献
119.
Alpana Kulhari Arun Sheorayan Sanjay Kalia Ashok Chaudhury Rajwant K. Kalia 《Genetic Resources and Crop Evolution》2012,59(6):1223-1254
Commiphora wightii (Arn.) Bhandari syn. C. mukul Engl. (Burseraceae) is an economically and pharmacologically important slow growing, dioecious, balsamiferous woody, multipurpose shrub heading towards extinction. Commonly known as “Guggul” due to the presence of steroidal compound guggulsterone in the oleo-gum resin, it has been used in treating various ailments and disorders since ancient times (2000 B.C.). Evaluation and confirmation of hypolipidemic effects of guggul based on Ayurvedic text in 1960s provided a new insight into its pharmacological applications. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering activities. Recently, it has been shown to have anti-cancerous activity also. It is found in the dry regions of Indian subcontinent, namely India, Pakistan and Bangladesh. Ruthless and unscientific harvesting of oleo-gum resin from the wild, by local populations, for economic benefits with negligible conservation efforts has made this species endangered and has led to its inclusion in Red Data Book of IUCN. Although this plant has many excellent traits, adequate attention has not been focused on its conservation and improvement. Conventional propagation methods i.e., seeds, cuttings and air layering are in place but have many limitations. Therefore, application of modern biotechnological tools needs to be standardized for harnessing maximum benefits from this pharmaceutically important plant. An efficient regeneration system needs to be in place for improvement of this genus through genetic transformation and production of useful metabolites in cell cultures. Studies are in progress for micropropagation through shoot multiplication and somatic embryogenesis, as well as for secondary metabolite (guggulsterone) production in callus cultures and bioreactors. No selected germplasm is available for C. wightii since it is a wild plant. Breeding programs have not yet been started due to lack of systematic cultivation and conservation programs. Moreover, little information has been gathered regarding the genetic variability in this species using RAPD and ISSR markers. No details are available about genetic makeup and QTL linkage maps. Investigations are in progress to search sex linked markers in this dioecious species. Research is also in progress to decipher the molecular mechanisms underlying various pharmacological actions of guggul. Since the approval of use of guggul as a food supplement by United States Food and Drug Administration in 1994, an exponential increase in research publications on various aspects of research on guggul have been published. Present communication summarizes the problems, progress made and suggests some future directions of research for this important endangered medicinal plant. 相似文献
120.
The antidiarrhoeal effects of the methanolic extract of Rhus javanica ripen fruits (MERJ) were investigated by employing four experimental models of diarrhoea in Swiss albino mice. MERJ treated mice, showed significant reduction in the faecal output and protected them from castor oil-induced diarrhoea. The extract also reduced the intestinal fluid secretion induced by MgSO4 and gastrointestinal motility after charcoal meal administration in the albino mice. No mortality and visible signs of general weakness was observed in the mice following the test extract administration up to 2000 mg/kg dose. 相似文献