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41.
The biodegradability of three types of bioplastic pots was evaluated by measuring carbon dioxide produced from lab-scale compost reactors containing mixtures of pot fragments and compost inoculum held at 58 °C for 60 days. Biodegradability of pot type A (composed of 100% polylactic acid (PLA)) was very low (13 ± 3%) compared to literature values for other PLA materials. Near infrared spectroscopy (NIRS) results suggest that the PLA undergoes chemical structural changes during polymer extrusion and injection molding. These changes may be the basis of the low biodegradability value. Biodegradability of pot types B (containing 5% poultry feather, 80% PLA, 15% starch), and C (containing 50% poultry feather, 25% urea, 25% glycerol), were 53 ± 2% and 39 ± 3%, respectively. More than 85% of the total biodegradation of these bioplastics occurred within 38 days. NIRS results revealed that poultry feather was not degraded during composting. 相似文献
42.
Dilanian RA Darmanin C Varghese JN Wilkins SW Oka T Yagi N Quiney HM Nugent KA 《Protein science : a publication of the Protein Society》2011,20(2):457-464
The application of powder diffraction methods to problems in structural biology is generally regarded as intractable because of the large number of unresolved, overlapping X‐ray reflections. Here, we use information about unit cell lattice parameters, space group transformations, and chemical composition as a priori information in a bootstrap process that resolves the ambiguities associated with overlapping reflections. The measured ratios of reflections that can be resolved experimentally are used to refine the position, the shape, and the orientation of low‐resolution molecular structures within the unit cell, in leading to the resolution of the overlapping reflections. The molecular model is then made progressively more sophisticated as additional diffraction information is included in the analysis. We apply our method to the recovery of the structure of the bacteriorhodopsin molecule (bR) to a resolution of 7 Å using experimental data obtained from two‐dimensional purple membrane crystals. The approach can be used to determine the structure factors directly or to provide reliable low‐resolution phase information that can be refined further by the conventional methods of protein crystallography. 相似文献
43.
44.
Mahbuba Moonmoon Nasrat Jahan Shelly Md. Asaduzzaman Khan Md. Nazim Uddin Kamal Hossain Mousumi Tania Saleh Ahmed 《Saudi Journal of Biological Sciences》2011,18(4):323-328
The cultivation of shiitake mushroom (Lentinus edodes) is increasing rapidly in Bangladesh due to its nutritional and medicinal importance with excellent flavor and longer shelf life. With the aim of increased production, we have cultivated L. edodes on saw dust (SD) supplemented with different levels (10%, 15%, 20%, 25%, 30%, 35% and 40%) of wheat bran (WB), rice bran (RB), maize powder (MP) and their combination (WB+RB+MP = 1:1:1) to investigate the growth, yield and quality of this mushroom. Most of the growth, yield and quality parameters varied significantly when mushrooms were cultivated with different levels of supplementation. The yield of mushroom was increased with the level of each supplementation upto a certain level, and then decreased. SD supplemented with 25% WB produced the highest number of fruiting bodies (34.8/500 g packet), highest biological yield (153.3/500 g packet), and biological efficiency (76.6%) of L. edodes. But the yield of the best quality mushroom was observed on SD with 40% WB supplementation; however, the qualities were not always supplementation dose dependent. In this study, we report that 25% WB supplementation with SD may be very effective for higher yield and 40% WB supplementation for better quality of L. edodes. 相似文献
45.
目的:研究超微七味白术散对抗生素引起的菌群失调小鼠的疗效。方法:将70只小鼠随机分为7组,以灌胃生理盐水建立对照组,以灌胃氨苄西林、头孢拉定、盐酸林可霉素复合抗生素构建菌群失调小鼠模型,以七味白术散传统汤剂及超微全量、1/2量、1/4量、1/8量治疗,通过粪便判断疗效。结果:七味白术散超微药剂与传统汤剂均能治疗抗生素引起的小鼠茵群失调,且超微七味白术散1/2量对小鼠的治疗效果已能达到传统汤剂水平。结论:超微七味白术散对菌群失调小鼠具有良好的治疗效果,与传统药物相比具有节约药材的价值。 相似文献
46.
目的:研究超微七味白术散对抗生素引起的菌群失调小鼠的疗效。方法:将70只小鼠随机分为7组,以灌胃生理盐水建立对照组,以灌胃氨苄西林、头孢拉定、盐酸林可霉素复合抗生素构建菌群失调小鼠模型,以七味白术散传统汤剂及超微全量、1/2量、1/4量、1/8量治疗,通过粪便判断疗效。结果:七味白术散超微药剂与传统汤剂均能治疗抗生素引起的小鼠菌群失调,且超微七味白术散1/2量对小鼠的治疗效果已能达到传统汤剂水平。结论:超微七味白术散对菌群失调小鼠具有良好的治疗效果,与传统药物相比具有节约药材的价值。 相似文献
47.
Preet A Gupta BL Siddiqui MR Yadava PK Baquer NZ 《Molecular and cellular biochemistry》2005,278(1-2):21-31
Vanadium has been reported to have broad pharmacological activity both in vitro and in vivo. Vanadium compound, sodium orthovanadate, Na3VO4, is well known for its hypoglycaemic effects. However, Na3VO4 exerts these effects at relatively high doses (0.6 mg/ml) and exhibit several toxic effects. In the present study lower doses
of Na3VO4 (0.2 mg/ml) are combined with Trigonella foenum graecum seed powder (TSP), another hypoglycaemic agent, to reduce its toxicity without compromising its antidiabetic potential. The
efficacy of the lower doses of Na3VO4 has been investigated in restoring the altered glucose metabolism and histological structure in the sciatic nerves in 21
and 60 days alloxan diabetic rats. A portion of the glucose was found to be channelled from the normal glycolytic route to
polyol pathway, evident by the reduced hexokinase activity and increased polyol pathway enzymes aldose reductase and sorbitol
dehydrogenase activity causing accumulation of sorbitol and fructose in diabetic conditions. Ultrastructural observation of
the sciatic nerve showed extensive demylination and axonal loss after eight weeks of diabetes induction. Blood glucose levels
increased in diabetic rats were normalized with the lower dose of vanadium and Trigonella treatment. The treatment of the diabetic rats with vanadium and Trigonella prevented the activation of the polyol pathway and sugar accumulations. The sciatic nerves were also protected against the
structural abnormalities found in diabetes with Trigonella foenum graecum as well as Na3VO4. Results suggest that lower doses of Na3VO4 may be used in combination with TSP as an efficient antidiabetic agent to effectively control the long-term complications
of diabetes in tissues like peripheral nerve. 相似文献
48.
Kim JY Cho SW Song WC Lee MJ Cai J Ohk SH Song HK Degan A Jung HS 《Differentiation; research in biological diversity》2005,73(5):240-248
Chick feather buds develop sequentially in a hexagonal array. Each feather bud develops with anterior posterior polarity, which is thought to develop in response to signals derived from specialized regions of mesenchymal condensation and epithelial thickening. These developmental processes are performed by cellular mechanisms, such as cell proliferation and migration, which occur during chick feather bud development. In order to understand the mechanisms regulating the formation of mesenchymal condensation and their role in feather bud development, we explanted chick dorsal skin at stage HH29+ with cytochalasin D, which inhibits cytoskeletal formation. We show that the aggregation of mesenchymal cells can be prevented by cytochalasin D treatment in a concentration-dependent manner. Subsequently, cytochalasin D disrupts the spacing pattern and inhibits feather bud axis formation as well. In addition, expression patterns of Bmp-4 and Msx-2, key molecules for early feather bud development, were disturbed by cytochalasin D treatment. Our results fully indicate that both the cytoskeletal structure and cell activity via gene regulation are of fundamental importance in mesenchymal condensation leading to proper morphogenesis of feather bud and spacing pattern formation. 相似文献
49.
Siddiqui MR Taha A Moorthy K Hussain ME Basir SF Baquer NZ 《Journal of biosciences》2005,30(4):483-490
Trigonella foenum graecum seed powder (TSP) and sodium orthovanadate (SOV) have been reported to have antidiabetic effects. However, SOV exerts hypoglycemic
effects at relatively high doses with several toxic effects. We used low doses of vanadate in combination with TSP and evaluated
their antidiabetic effects on antioxidant enzymes and membrane-linked functions in diabetic rat brains. In rats, diabetes
was induced by alloxan monohydrate (15 mg/100 g body wt.) and they were treated with 2 IU insulin, 0.6 mg/ml SOV, 5% TSP and
a combination of 0.2 mg/ml SOV with 5% TSP for 21 days. Blood glucose levels, activity of superoxide dismutase (SOD), catalase
(CAT), glutathione peroxidase (GPx), Na+/K+ ATPase, membrane lipid peroxidation and fluidity were determined in different fractions of whole brain after 21 days of treatment.
Diabetic rats showed high blood glucose (P < 0.001), decreased activities of SOD, catalase and Na+/K+ ATPase (P < 0.01,P < 0.001 andP < 0.01), increased levels of GPx and MDA (P < 0.01 andP < 0.001) and decreased membrane fluidity (P < 0.01). Treatment with different antidiabetic compounds restored the above-altered parameters. Combined dose ofTrigonella and vanadate was found to be the most effective treatment in normalizing these alterations. Lower doses of vanadate could
be used in combination with TSP to effectively counter diabetic alterations without any toxic effects. 相似文献
50.
Anduleit K Sutton G Diprose JM Mertens PP Grimes JM Stuart DI 《Protein science : a publication of the Protein Society》2005,14(10):2741-2743
Many insect viruses survive for long periods by occlusion within robust crystalline polyhedra composed primarily of a single polyhedrin protein. We show that two different virus families form polyhedra which, despite lack of sequence similarity in the virally encoded polyhedrin protein, have identical cell constants and a body-centered cubic lattice. It is almost inconceivable that this could have arisen by chance, suggesting that the crystal lattice has been preserved because it is particularly well-suited to its function of packaging and protecting viruses. 相似文献