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排序方式: 共有873条查询结果,搜索用时 3 毫秒
1.
This paper examined the growth and yield performance of Lentinus citrinus on cupuaçu exocarp (Theobroma grandiflorum) mixed with litter (CE + LI) or rice bran (Oryza sativa) (CE + RB) in the ratio of 2:1 (800 g:200 g) to investigate the nutritional composition and proteolytic potential of the fruiting body produced. Significance values of yield were determined on substrate combinations. In CE + LI the biological efficiency of the mushrooms was 93.5% and the content of fat (4.5%), fiber (11.0%), protein (27.0%) and amino acids were higher when compared with CE + RB. Among the amino acids, the amount of glutamic acid, aspartic acid, alanine, arginine and leucine was high. The biological efficiency on CE + RB reduced to 84.2% and based on the nutritional value, carbohydrates (53.59%), energy (324.33 kcal) and minerals such as zinc, iron, copper, potassium and phosphorus were higher in this substrate combination. Protease activity from fruiting body was significant in CE + LI (463.55 U/mL). This protease showed an optimal activity at 50 °C in neutral and alkaline pH with maximum stability at 30 °C at alkaline pH. This is the first report of L. citrinus fruiting body nutritional composition with potential for human food and application in industrial processes.  相似文献   
2.
目的:观察中药制剂榄香烯联合GP化疗方案治疗晚期肺腺癌脑转移的疗效。方法:选取2009年6月28日至2011年5月30日就诊于我院的晚期肺腺癌脑转移患者34例,将34例晚期肺腺癌脑转移患者随机分为两组(A组和B组),A组:治疗组,17例,并给予患者榄香烯静脉滴注和GP化疗方案;B组:对照组,17例,给予患者GP化疗方案;观察两组疗效和安全性,并记录治疗前后相关的指标变化。结果:2个疗程的化疗结束后,A组:10例患者复查脑核磁发现脑转移瘤较前缩小,病灶部分缓解(P R);6例脑转移瘤病灶稳定(SD);1例疾病进展(PD);B组:5例患者复查脑核磁发现脑转移瘤较前缩小,病灶部分缓解(P R);9例脑转移瘤病灶稳定(SD);3例疾病进展(PD)。结论:采用榄香烯联合GP化疗方案治疗晚期肺腺癌脑转移,能有效地改善患者生活质量,疗效满意。  相似文献   
3.
研究从生长、健康和营养价值方面评估了高水平的双低菜粕替代饲料鱼粉对大黄鱼潜在的危害。在鱼粉含量60%的基础饲料(FM)上按照质量分数用双低菜粕分别替代15%(CM15)、30%(CM30)、60%(CM60)和100%(CM100)的鱼粉,配制成5种实验饲料。每种饲料投喂5个网箱的大黄鱼[初重(135.38±1.02)g],即每个处理5个重复,进行12周的养殖实验。结果表明,当双低菜粕替代水平在15%和30%时,大黄鱼的生长及饲料系数并没有受到显著性的影响。然而,当替代水平高于30%时,大黄鱼的末重和特定生长率均显著降低,而饲料系数显著升高(P < 0.05)。当替代水平达到100%时,大黄鱼摄食率达到最高值而肥满度达到最低值(P < 0.05)。在组织形态方面,大黄鱼摄食双低菜粕替代的饲料后肠道绒毛的弯曲程度减少并且排列更加不规则,而肝细胞则呈现出圆形空泡状并伴随着细胞核的偏移。对大黄鱼骨骼进行X-射线扫描发现,摄食双低菜粕的大黄鱼椎体和头部出现了畸形。在营养价值方面,双低菜粕替代鱼粉并未显著影响大黄鱼背肌的脂肪含量、蛋白含量和氨基酸组成,然而脂肪酸组成受到了显著影响,即N-6系列脂肪酸含量显著升高,而DHA与EPA含量显著降低(P < 0.05)。根据欧洲食品安全局(EFSA)的相关标准,这些营养价值的变化并没有影响大黄鱼作为健康食品的功能。由此可见,高水平(60%和100%)的双低菜粕替代鱼粉对大黄鱼的负面影响主要表现为降低大黄鱼的生长性能、改变肠道和肝脏组织形态,以及影响大黄鱼的骨骼健康。然而,双低菜粕替代鱼粉养殖大黄鱼的肌肉仍然符合人类的膳食要求。因此,双低菜粕替代鱼粉并没有影响大黄鱼作为食用鱼的营养价值。  相似文献   
4.
Evidence for PDZ domains in bacteria, yeast, and plants.   总被引:18,自引:0,他引:18       下载免费PDF全文
Several dozen signaling proteins are now known to contain 80-100 residue repeats, called PDZ (or DHR or GLGF) domains, several of which interact with the C-terminal tetrapeptide motifs X-Ser/Thr-X-Val-COO- of ion channels and/or receptors. PDZ domains have previously been noted only in mammals, flies, and worms, suggesting that the primordial PDZ domain arose relatively late in eukaryotic evolution. Here, techniques of sequence analysis-including local alignment, profile, and motif database searches-indicate that PDZ domain homologues are present in yeast, plants, and bacteria. It is suggested that two PDZ domains occur in bacterial high-temperature requirement A (htrA) and one in tail-specific protease (tsp) homologues, and that a yeast htrA homologue contains four PDZ domains. Sequence comparisons suggest that the spread of PDZ domains in these diverse organisms may have occurred via horizontal gene transfer. The known affinity of Escherichia coli tsp for C-terminal polypeptides is proposed to be mediated by its PDZ-like domain, in a similar manner to the binding of C-terminal polypeptides by animal PDZ domains.  相似文献   
5.
Sensitivity to and requirement for iron in Plantago species   总被引:1,自引:0,他引:1  
  相似文献   
6.
海河流域生态需水核算   总被引:19,自引:2,他引:17  
魏彦昌  苗鸿  欧阳志云  王效科 《生态学报》2004,24(10):2100-2107
从生态系统角度分析了生态需水内涵和生态需水与生态用水概念的差别。探讨了海河流域自然陆地、河流、湿地、城市 4种生态系统类型生态需水核算方法 ,并对其生态需水量进行了核算。大气降水首先被天然植被利用后形成地表径流 ,才能被人类管理利用来满足经济水量和生态水量需求。从水资源管理来说 ,河流、湿地、城市等生态需水来源于径流性水资源可称为狭义生态需水 ,而包括利用降水性水资源的天然植被生态需水在内的全部生态系统生态需水可认为是广义的生态需水。狭义生态需水是水资源管理及生态需水研究和关注的重心。研究结果表明 :海河流域河流生态需水 31.6 4× 10 8m3,占多年平均天然径流量的 12 % ;湿地生态需水为 34.31× 10 8m3,占 13% ;城市生态需水量 10 .83× 10 8m3,占 4 .1% ,3项合计占径流总量的 2 9.1%。生态需水量是一个动态的值 ,随生态保护目标的提高和经济的发展核算结果必然发生变化 ,维护生态环境质量的状况不同 ,也存在最大、最小生态需水量的阈值问题 ,此类问题需今后进一步研究  相似文献   
7.
Water scarcity is a widespread problem in many parts of the world. Most previous methods of water scarcity assessment only considered water quantity, and ignored water quality. In addition, the environmental flow requirement (EFR) was commonly not explicitly considered in the assessment. In this study, we developed an approach to assess water scarcity by considering both water quantity and quality, while at the same time explicitly considering EFR. We applied this quantity–quality-EFR (QQE) approach for the Huangqihai River Basin in Inner Mongolia, China. We found that to keep the river ecosystem health at a “good” level (i.e., suitable for swimming, fishing, and aquaculture), 26% of the total blue water resources should be allocated to meet the EFR. When such a “good” level is maintained, the quantity- and quality-based water scarcity indicators were 1.3 and 14.2, respectively; both were above the threshold of 1.0. The QQE water scarcity indicator thus can be expressed as 1.3(26%)|14.2, indicating that the basin was suffering from scarcity problems related to both water quantity and water quality for a given rate of EFR. The current water consumption has resulted in degradation of the basin's river ecosystems, and the EFR cannot be met in 3 months of a year. To reverse this situation, future policies should aim to reduce water use and pollution discharge, meet the EFR for maintaining healthy river ecosystems, and substantially improve pollution treatment.  相似文献   
8.
9.
The liver is more prone to infections that cause fibrosis, such as steatosis, non-alcoholic steatohepatitis, hepatotoxicity, cirrhosis, and hepatocellular carcinoma. Also, Viral hepatitis is a common condition worldwide it worsens into chronic inflammation of the liver. One of the healthiest fruits is the pomegranate for the body and health, as it contains a high nutritional value of minerals, vitamins, antioxidants, so we worked on this investigation to magnify the therapeutic applications of pomegranate fruits (POF) and peel (POP) in carbon tetrachloride-injected rats (Ccl4). The experiment was carried out in a caged animal. All rats were fed a basal diet for one week before the study, and they were divided into seven groups, each with six rats. As a control negative group (C–ve), the first group sample was fed only the basal diet for 28 days. The remaining rats (n = 36) were injected with carbon tetrachloride (Ccl4). Five groups were fed varying concentrations of (5 %, 10 %, 15 % POF, 5 %, and 10 % pomegranate peel (POP)), whereas one group was diagnosed with the illness and disease, and didn't even feed the experimental diet. The results revealed significant increases in T.BIL, D.BIL, and BIL in the serum of rats injected by CC14 to induce hepatopathy compared to the healthy group (normal rats). Also, the best treatment considering the serum D.BIL was recorded for the 5 % POF.  相似文献   
10.
南极拟扇虾肌肉营养成分分析   总被引:2,自引:0,他引:2  
南极拟扇虾(Parribacus antarcticus Lund)隶属于甲壳纲(Crustacea)、十足目(Decapoda)、爬行亚目(Reptantia)的龙虾类(Palinura)中的蝉虾科(Scyllaridae),分布于我国台湾、南海,栖息于10—150 m深浅不等的暖水区域。南极拟扇虾耐饥饿强、成活率高、肉质细滑、风味独特,在南方沿海一带深受欢迎,是一种稀有的名贵品种,价格  相似文献   
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