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91.
沈建仁 《国外畜牧学(猪与禽)》2002,(2):28-29
最近有顾客向笔者提出了一个问题 :增加母猪泌乳期采食量有什么价值 ?这使我想起 ,人们比较了解增加母猪泌乳期采食量对母猪繁殖性能的好处 ,却不太了解这对仔猪生长有多大好处。毫无疑问 ,我们都知道 ,增加泌乳母猪的采食量可改善母猪的繁殖性能。母猪在泌乳期内体脂和机体蛋白质损失得越少 ,则断奶后恢复发情就越快 ,下一胎的窝产仔数往往也越大。对猪群生产记录的研究分析表明 ,一头母猪在泌乳期间每丧失 1千克体重 ,则断奶后发情就推迟一天。同样 ,母猪泌乳期间每丧失 1 0 %体脂 ,下一胎的窝产仔数就减少一头。增加母猪泌乳期采食量对仔… 相似文献
92.
Park KK Liu K Hu Y Smith PD Wang C Cai B Xu B Connolly L Kramvis I Sahin M He Z 《Science (New York, N.Y.)》2008,322(5903):963-966
The failure of axons to regenerate is a major obstacle for functional recovery after central nervous system (CNS) injury. Removing extracellular inhibitory molecules results in limited axon regeneration in vivo. To test for the role of intrinsic impediments to axon regrowth, we analyzed cell growth control genes using a virus-assisted in vivo conditional knockout approach. Deletion of PTEN (phosphatase and tensin homolog), a negative regulator of the mammalian target of rapamycin (mTOR) pathway, in adult retinal ganglion cells (RGCs) promotes robust axon regeneration after optic nerve injury. In wild-type adult mice, the mTOR activity was suppressed and new protein synthesis was impaired in axotomized RGCs, which may contribute to the regeneration failure. Reactivating this pathway by conditional knockout of tuberous sclerosis complex 1, another negative regulator of the mTOR pathway, also leads to axon regeneration. Thus, our results suggest the manipulation of intrinsic growth control pathways as a therapeutic approach to promote axon regeneration after CNS injury. 相似文献
93.
Ioannis K. Kalavrouziotis Prodromos H. Koukoulakis Georgia Ntzala Aristotelis H. Papadopoulos 《Water, air, and soil pollution》2012,223(8):5189-5196
The assessment of soil pollution with heavy metals has been studied, based on experimental soil and plant analytical heavy metal data obtained by a pot experiment conducted during 2010?C2011 in a green house. A completely randomized block design was used, including the following sludge treatments (in tons per hectare): 0, 6, 12, 18, 24, 30, and (30+treated wastewater) in four replications. Lettuce (Lactuca sativa L.) var. longifolia was used as a test plant. Three indices were proposed, i.e., (1) elemental pollution index, (2) heavy metal load, and (3) total concentration factor. They were found to be linearly and statistically significantly related to the pollution load index, which was used as a reference index, and curvilinearly related to lettuce dry matter yield. It was concluded that the above indices could be used for the assessment of soil pollution level. 相似文献
94.
Purpose
Polycyclic aromatic hydrocarbons (PAHs) are widespread in sediments, particularly near areas of intense human activities. Due to their mutagenic and carcinogenic behaviour, PAHs are classified as priority contaminants to be monitored in environmental quality control schemes. The purpose of this study was to determine the levels of PAHs in major coastal areas of Greece that receive various pressures, investigate their sources and evaluate their potential toxicity by comparison against effects-based Sediment Quality Guidelines (SQG). 相似文献95.
Simulation of Groundwater Flow in a Sedimentary Aquifer System Subjected to Overexploitation 总被引:1,自引:0,他引:1
Andreas Kallioras Fotios Pliakas Ioannis Diamantis 《Water, air, and soil pollution》2010,211(1-4):177-201
Groundwater flow models are applied to a large variety of hydrogeological conditions in different aquifer types, in order to simulate the groundwater flow of the investigated system. This paper aims to present the application of a groundwater flow model for the simulation of a sedimentary aquifer, located in Northern Greece. The simulation involves the period between April 2003 and April 2004, and the model is divided into two distinct stress periods, each containing two different time steps. The simulation of the aquifer is found to be satisfactory, conclusion which is based on both graphical as well as arithmetical verifications. The groundwater flow simulation was achieved by the application of the MODFLOW code. 相似文献
96.
97.
Savvas I Anagnostou T Papazoglou LG Raptopoulos D 《Veterinary anaesthesia and analgesia》2006,33(3):175-178
BACKGROUND: Extradural lidocaine exerts several adverse effects which are seldom fatal. While cardiac arrest following extradural lidocaine injection has been reported in human beings, it has not hitherto been reported in dogs. OBSERVATIONS: The emergency management of a dog with complete urethral obstruction is described. We intended to perform vaginoscopy and cystostomy under extradural lidocaine anaesthesia, but cardiac asystole occurred a few minutes after injection. Resuscitation was successful. About 20 minutes later cardiac arrest recurred, and was treated successfully. The dog remained hypothermic for approximately 7 hours. Complete recovery without neurological deficit occurred the next day and the dog remained normal for at least 3 months. The probable cause of the problem was cranial lidocaine dispersion causing a drop in cardiac preload and cardiac arrest. The successful neurological outcome was attributed to early diagnosis and effective treatment. Hypothermia may have conferred cerebral protection during ischemia. CONCLUSIONS: Extradural local anaesthetic administration is not without risk and the technique should be tailored to individual animals. Constant monitoring is required to detect potentially fatal complications and increase the likelihood of successful outcome. 相似文献
98.
Katikou P Georgantelis D Paleologos EK Ambrosiadis I Kontominas MG 《Journal of agricultural and food chemistry》2006,54(12):4277-4283
The biogenic amine (BA) content of vacuum-packed filleted rainbow trout (Oncorhynchus mykiss) inoculated or not with two different Lactobacillus strains, individually or in combination, was monitored during refrigerated storage for 20 days and related to respective bacteriological and sensory changes occurring during the same period. Eight amines, namely putrescine, cadaverine, tyramine, tryptamine, beta-phenylethylamine, histamine, spermine, and spermidine, were determined, whereas agmatine was not detected in any of the samples. In all cases, BA concentration was higher (P < or = 0.05) in the controls compared to all inoculated treatments, whereas the trend with regard to the bacterial populations (Enterobacteriaceae, pseudomonads, and H2S-producing bacteria) and the off-odor scores was similar. Inoculation with Lactobacillus sakei CECT 4808 showed the best preservative effect among inoculated treatments. Concentrations of putrescine and cadaverine, the main BAs formed, correlated well with both spoilage bacterial counts and off-odor scores and can be useful indicators of shelf life. Spermine and spermidine contents decreased during storage, while levels of the other determined BAs remained below 10 mg/kg even after sensory rejection. 相似文献
99.
Mourtzinos I Salta F Yannakopoulou K Chiou A Karathanos VT 《Journal of agricultural and food chemistry》2007,55(20):8088-8094
Olive leaf extract, rich in oleuropein, formed an inclusion complex with beta-cyclodextrin (beta-CD) upon mixing of the components in aqueous media and subsequent freeze-drying. Inclusion complex formation was confirmed by differential scanning calorimetry (DSC). DSC thermograms indicated that the endothermic peaks of both the olive leaf extract and the physical mixture of olive leaf extract with beta-CD, attributed to the melting of crystals of the extract, were absent in DSC thermogram of inclusion complex. Moreover, DSC studies under oxidative conditions indicated that the complex of olive leaf extract with beta-CD was protected against oxidation, since it remained intact at temperatures where the free olive leaf extract was oxidized. Phase solubility studies afforded A L type diagrams, 1:1 complex stoichiometry, a moderate binding constant ( approximately 300 M (-1)), and an increase of the aqueous solubility by approximately 50%. The formation of the inclusion complex was also confirmed by nuclear magnetic resonance (NMR) studies of beta-CD solutions in the presence of both pure oleuropein and olive leaf extract. The NMR data have established the formation of a 1:1 complex with beta-CD that involves deep insertion of the dihydroxyphenethyl moiety inside the cavity from its secondary side. 相似文献
100.
Panagiotis A Papamichalis Kalliopi Zachou George K Koukoulis Aikaterini Veloni Efthimia G Karacosta Lampros Kypri Ioannis Mamaloudis Stella Gabeta Eirini I Rigopoulou Ansgar W Lohse George N Dalekos 《Journal of Autoimmune Diseases》2007,4(1):3