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101.
Wei S  He W  Lu J  Wang Z  Yamashita K  Yokoyama M  Kodama H 《Fitoterapia》2012,83(2):402-407
Five oleanolic acid triterpenoid saponins (OTS-1, 2, 3, 4 and 5) were isolated from the rhizome of Anemone raddeana. The effect of these triterpenoid saponins on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of ferricytochrome c using a dual-beam spectrophotometer. The phosphorylation of neutrophil proteins, and translocation of p67(phox), p47(phox) and Rac to plasma membrane were investigated using specific monoclonal antibodies. The five oleanolic acid triterpenoid saponins used in this experiment suppressed N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner. OTS-1, 2 and 4 suppressed phorbol 12-myristate 13-acetate (PMA)- and arachidonic acid (AA)-induced superoxide generation in a concentration-dependent manner, but OTS-3 and 5 showed no effect. fMLP- and PMA-induced tyrosyl or serine/threonine phosphorylation, and fMLP-, PMA- and AA-induced translocation of p67(phox), p47(phox) and Rac to plasma membrane were in parallel with the suppression of the stimulus-induced superoxide generation.  相似文献   
102.
An experiment was conducted using 17 male buffalo calves to assess the effects of plane of nutrition on dry matter intake (DMI), daily gain (DG), body size measurement, apparent digestibility and nitrogen (N) balance. To attain 250 kg BW, the calves were allocated into three groups: H, L‐H and L, receiving the concentrate at 1.50% of BW, 0.75% of BW until 190 kg BW and 1.50% thereafter and 0.75% of BW, respectively. The animals had ad libitum access to urea‐treated rice straw (UTRS). The DMI of UTRS through the experiment was higher in L and L‐H than H, showing 3.52, 2.90 and 2.62 kg/day, respectively (P < 0.01), but the total DMI did not differ among the treatment groups. The DG throughout the experiment was high in the order of H, L‐H and L, showing 0.72, 0.57 and 0.45 kg, respectively (P < 0.01). The digestibility of DM, organic matter, crude protein, neutral and acid detergent fiber and N retention were higher in H than in L (P < 0.05). The findings of this study thus revealed the greater DG has an advantage of shortening the growing period around 3 months, and consequently increasing benefit in fattening of buffalo calves in Nepal.  相似文献   
103.
An experiment was conducted using 17 male buffalo calves to assess the effects of plane of nutrition on slaughtering traits and meat characteristics. To attain 250 kg body weight (BW), the calves were allocated into three groups: high (H), low‐high (L‐H) and low (L) corresponding to concentrate levels receiving the concentrate at 1.50% of BW, 0.75% of BW until 190 kg BW and 1.50% thereafter, and 0.75% of BW, respectively. The animals had ad libitum access to urea‐treated rice straw. No significant differences of hot carcass weight, dressing percentage and lean fat–bone yields were observed among the treatment groups. The L group had heavier brisket weight and lower percentage of round weight in the hot carcass than the H and L‐H groups (P < 0.05). The H group had heavier hearts than the L group, and the H and L‐H groups had heavier livers and kidneys than the L group (P < 0.05). There was no significant difference of rib eye area, pH and the contents of moisture, crude protein and fat in loin meat among the groups. The findings indicated that the effects of plane of nutrition affected the weight or percentages of some cut yields in the hot carcasses and internal organs.  相似文献   
104.
The purification and characterization of a bacteriocin produced by Leuconostoc mesenteroides strain 406 that was isolated from traditional Mongolian fermented mare's milk, airag, were carried out. Leuconostoc mesenteroides strain 406 was identified on the basis of its morphological and biochemical characteristics and carbohydrate fermentation profile and by API 50 CH kit and 16S ribosomal DNA analyses. The neutral‐pH cell‐free supernatant of this bacterium inhibited the growth of several lactic acid bacteria and food spoilage and pathogenic organisms, including Listeria monocytogenes and Clostridium botulinum. The bacteriocin was heat‐stable and not sensitive to acid and alkaline conditions, but was sensitive to several proteolytic enzymes such as pepsin, pronase E, proteinase K, trypsin, and α‐chymotrypsin, but not catalase. Optimum bacteriocin production (4000 activity units/mL) was achieved when the strain was cultured at 25°C for 24–36 h in Man Rogosa Sharpe medium. The bacteriocin was partially purified by ammonium sulfate precipitation (80% saturation), dialysis (cut‐off MW: 1000), and gel filtration chromatography. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis revealed that the bacteriocin had a molecular weight of approximately 3.3 kDa. To our knowledge, this is the first report of the isolation of a bacteriocin‐producing Leuconostoc strain from airag. An application to fermented milks would be desired.  相似文献   
105.
Both stem and crown mass affect tree resistance to uprooting   总被引:1,自引:0,他引:1  
To examine the hypothesis that both stem and crown mass affect the resistance of a tree to uprooting and that tree resistance increases with increasing crown mass, we conducted tree-pulling experiments on three Picea glehnii plantations (stands A, B, and C: 27–32 years old) that differed in tree density and slenderness ratio. Allometries between crown and stem masses and between the critical uprooting moment and stem mass differed significantly among the three stands, with the crown mass and critical moment significantly larger in stand C than in stands A or B, despite the same stem mass. These results quantitatively verified our hypothesis. Allometries between crown and stem masses and between critical uprooting moment and stem mass were highly significant in each stand but were stand specific. Therefore, these allometries can be used to estimate tree resistance to uprooting in a given stand but not for data compiled from stands of various conditions and tree shapes. The allometry between critical moment and aboveground mass did not differ among the three Picea stands; thus, it is not stand specific and is generally appropriate to use for estimating tree resistance. To increase tree resistance to uprooting, we recommend light management for Picea glehnii plantations and probably other coniferous plantations as well.  相似文献   
106.
The thermal properties and transitions of solid and ground wood samples conditioned at different humidity conditions were investigated by temperature-modulated differential scanning calorimetry. A time-dependent transition was detected as an endothermic peak in the total and non-reversing heat flows and as a step change in the reversing heat flow during the first heating run of samples with moisture contents above 5?%, but it disappeared in the second heating run. These different thermal behaviors indicate that the effect of heat and moisture on the thermal properties of wood is history dependent. This step change in the reversing heat flow is considered to be a glass transition of moist wood. Other relaxation processes (e.g., enthalpy relaxation) occur simultaneously with this glass transition. The temperature ranges of the transition and the relaxation decreased drastically as the moisture content increased up to 11?%, while they remained almost constant at higher moisture contents. In addition, the transitions of the ground wood occurred at lower temperatures than those of the solid wood at similar moisture contents. Kissinger plots revealed that the apparent activation energy for the glass transition of the solid wood with a moisture content of 11?% was about 600?kJ/mol, whereas that of the ground wood was 220?kJ/mol.  相似文献   
107.
Three types of bamboo pellets as a ruminant feed: P1 (ground bamboo (GB) cultured with the fungus Ceriporiopsis subvermispora (CGB) : soybean curd residue (T) : soy sauce cake (S) in a 5:4:1 ratio on a dry matter (DM) basis); P2 (GB : T : S = 5:4:1 on a DM basis); and P3 (CGB : T : S = 5.5:0.8:3.7 on a DM basis) were prepared. Four wethers were assigned in a 4 × 4 Latin square design experiment to evaluate the applicability of the bamboo pellets. The experimental treatments were C (control): fed alfalfa hay cubes (AC) only, and T1, T2 and T3: fed P1, P2, and P3 with AC by 1:1 on a DM basis, respectively. The digestibility of the DM, organic matter and acid detergent fiber of P1 were significantly higher than those of P2 and P3 (P < 0.05). The total digestible nutrient (TDN) contents of AC, P1, P2 and P3 were 56.5%, 60.2%, 53.2% and 47.0%, respectively. No significant differences in nitrogen retention or ruminal pH and NH3 were observed among the treatment groups. The results indicate that bamboo pellets cultured with C. subvermispora and mainly mixed with soybean curd residue improved nutritional quality of ground bamboo because of its high digestibility and TDN content.  相似文献   
108.
The establishment of a classification system for domestic animals on consumed feed stuff is thought to be important from both a hygiene and market point of view. We collected plasma samples of Romney lambs (Ovis aries) which were fed one of the following: a herb‐clover mix (n = 10) which included chicory, red clover, white clover and plantain; a plant‐grass mix (n = 10) which included plantain, ryegrass and white clover; or a grass mix (n = 10) which included ryegrass and white clover. A total of 20 elements in plasma samples obtained from the lambs were analyzed using inductively coupled plasma mass spectrometry. The data were then analyzed by principal component analysis. The lambs were divided into three groups on a score plot depending on the different feed conditions. Furthermore, discriminant analyses of the elements were examined, using linear discriminant analysis with forward stepwise regression. This discriminant function correctly classified the samples from each group. The accuracy of classification of each group, as shown by 10‐fold cross‐validation, proved the effectiveness of the established discriminant function. It is concluded that using linear discriminant analysis might be a useful tool for the validation of elements from plasma in lambs grown in different conditions.  相似文献   
109.
To understand the viscoelasticity of wood three dimensionally, matched samples of Japanese cypress were loaded in uniaxial tensile creep in the longitudinal (L), radial (R), and tangential (T) directions at approximately 9.7 % equilibrium moisture content. Longitudinal and transverse strains were measured for the determination of viscoelastic Poisson’s ratios and three-dimensional viscoelastic compliance tensors concerning the normal strain. The changes in the transverse strains showed the same tendencies as those in the longitudinal strains, in all directions of loading. That is, during creep, the absolute value of transverse strain continued to increase with the gradual reduction in the increase rate; immediately after the removal of the load, it recovered rapidly, after which it continued to recover slowly. The transverse strain increased most easily in the T direction, followed by R and L, during creep. All the viscoelastic Poisson’s ratios and the absolute values of all elements of the viscoelastic compliance increased logarithmically with creep time. The three-dimensional viscoelastic compliance matrix for Japanese cypress is concluded to be asymmetric.  相似文献   
110.
In porcine oocytes, the function of the zona pellucida (ZP) with regard to sperm penetration or prevention of polyspermy is not well understood. In the present study, we investigated the effects of the ZP on sperm penetration during in vitro fertilization (IVF). We collected in vitro-matured oocytes with a first polar body (ZP+ oocytes). Some of them were freed from the ZP (ZP− oocytes) by two treatments (pronase and mechanical pipetting), and the effects of these treatments on sperm penetration parameters (sperm penetration rate and numbers of penetrated sperm per oocyte) were evaluated. There was no evident difference in the parameters between the two groups. Secondly, we compared the sperm penetration parameters of ZP+ and ZP− oocytes using frozen-thawed epididymal spermatozoa from four boars. Sperm penetration into ZP+ oocytes was found to be accelerated relative to ZP− oocytes. Thirdly, we evaluated the sperm penetration of ZP+ and ZP− oocytes at 1−10 h after IVF (3 h gamete co-incubation). The proportions of oocytes penetrated by sperm increased significantly with time in both groups; however, the number of penetrated sperm per oocyte did not increase in ZP− oocytes. Finally, we performed IVF using ZP− oocytes divided into control (3 h) and prolonged gamete co-incubation (5 h) groups. Greater numbers of sperm penetrated in the 5 h group than in the control group. These results suggest that the ZP and oolemma are not competent factors for prevention of polyspermy in our present porcine IVF system. However, it appears that ZP removal is one of the possibilities for reducing polyspermic penetration in vitro in pigs.  相似文献   
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