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1.
Colostrum is essential for good neonate health; however, it is not known whether different calves absorb the nutrients from colostrum equally well. In this study, the absorption of protein, IgG, and γ-glutamyl transferase was compared in newborn dairy bull calves for 1 wk after feeding colostrum from different sources. Thirty-five Holstein-Friesian bull calves were randomly allocated into 3 groups and fed colostrum within 4 h after birth. Group A calves (n = 12) were bottle fed colostrum from their own dam for 3 d. Colostrum from these group A cows was also used as foster cow colostrum for the group B calves (n = 12), such that each group A and B calf pair received identical colostrum from each milking of the respective group A dam (10% of birth weight per day). The group C calves (n = 11) were fed 1 bottle (2 L) of pooled colostrum and transition milk (referred to as pooled colostrum), as was the standard practice on the dairy farm. The pooled colostrum was collected from the other dairy cows on the farm 0 to 4 d postpartum and stored at 4°C for less than 12 h. Blood was sampled from calves before the first feeding and at 1, 2, 3, and 7 d after birth. Levels of total solids, total protein, and IgG were higher in the dam colostrum than in the pooled colostrum. At birth, there were no differences between the calf groups for any measurements, and all calves had very low IgG levels. After receiving colostrum, the glucose, plasma γ-glutamyl transferase, serum total protein, and IgG concentrations increased significantly in all calves. There were no differences in any blood measurements at any time point between the pairs of group A and group B calves that received colostrum from the same cow except for the IgG concentration 2 d after birth. However, the group A calves had a higher total serum protein level and IgG concentration than the group C calves for all the time points after the first feeding. The group B calves had a higher IgG concentration than the group C calves on d 1, 2, and 7 after birth. Compared with groups A and B, there was no difference in the proportion of calves in group C that failed to have passive immunity transferred adequately based on the IgG threshold (<10 g/L). Thus, the calves receiving identical colostrum from the same cow had the same levels of IgG, and even the pooled colostrum provided sufficient transfer of IgG as the calves were fed within 4 h after birth.  相似文献   
2.
Abstract— Transition fracture toughness was studied to look at the effect of size, thickness and geometry. Size effects were studied on six sets of data collected from the literature in which proportionally sized compact specimens of various steels were tested. Thickness effects were studied on tests of compact specimens of constant thickness and varying planar dimensions. Tests were conducted on a pressure vessel steel at a constant thickness of 20 mm where planar dimensions were increased so that thickness constraint was decreased. Geometry effects were studied on tests from a center cracked tension specimen geometry. Initially all of the data from the tests were included in the study; none were eliminated due to a size or other validity requirement. Then two validity requirements, the K Ic and the Anderson-Dodds size requirements, were imposed to study their effect on the data.
The results showed that a smaller specimen size does not necessarily result in higher toughness. Rather, the smallest size often gave the lowest values of toughness. Loss of thickness constraint tended to increase toughness but not very much; it may not increase at all at the lower temperatures. The center cracked tension geometry appeared to have a lower constraint. These specimens showed an increase in toughness which is similar to that observed on a compact specimen for a change of temperature from −90°C to −60°C. Imposing a size validity requirement eliminated much of the fracture toughness data in the transition and influenced the distribution of data. Validity size criteria should be avoided if possible, especially for a scientific study.  相似文献   
3.
Some technological methods employed in the production of new canned foods prepared with chicken meat and intended for 5-7 month old infants were investigated. Biological experiments established the limits for the thermal optimum of sterilization within the range of 125-130 degrees for the new canned goods of the type "Kroshka". Furthermore, the most marked loss of the proteinic value of the canned goods with the use of modified starches--the jellyfying potato and the corn phosphatethan by employing native starches as a structural stabilizer, was ascertained. The need for hygienic evaluation of the technological methods in developing new baby and dietic foods is stressed.  相似文献   
4.
Kiro Mojsov 《纺织学会志》2017,108(7):1136-1143
The enzymatic treatment of textiles significantly improves some of their physicochemical properties as well as increases their aesthetic values and comfort of use. Enzymes are used in order to develop environmentally friendly processes by reducing the concentration of chemical agents, water and energy consumption. In the present study, an attempt was made to treat the wool fabric with different concentrations (1, 3, and 5 g/L) of protease enzyme and observed the effects on physical and chemical properties including softness, absorbency, pilling resistance, weight loss, tensile strength loss, water retention, felting shrinkage, alkali solubility and urea-bisulphite solubility of wool fabric. The results of pretreated and enzyme-treated samples are compared to those obtained for untreated wool fabric. Enzyme-treated wool fabrics showed improvement in softness, absorbency, pilling resistance and felting shrinkage and a slight increase in weight loss, tensile strength loss, alkali solubility and urea-bisulphite solubility, and decrease in water retention of the fabric.  相似文献   
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Significant antiproliferative effects against various tumor cell lines were observed with novel ampicillin salts as ionic liquids. The combination of anionic ampicillin with appropriate ammonium, imidazolium, phosphonium, and pyridinium cations yielded active pharmaceutical ingredient ionic liquids (API‐ILs) that show potent antiproliferative activities against five different human cancer cell lines: T47D (breast), PC3 (prostate), HepG2 (liver), MG63 (osteosarcoma), and RKO (colon). Some API‐ILs showed IC50 values between 5 and 42 nM , activities that stand in dramatic contrast to the negligible cytotoxic activity level shown by the ampicillin sodium salt. Moreover, very low cytotoxicity against two primary cell lines—skin (SF) and gingival fibroblasts (GF)—indicates that the majority of these API‐ILs are nontoxic to normal human cell lines. The most promising combination of antitumor activity and low toxicity toward healthy cells was observed for the 1‐hydroxyethyl‐3‐methylimidazolium–ampicillin pair ([C2OHMIM][Amp]), making this the most suitable lead API‐IL for future studies.  相似文献   
8.
The influence of subjective (individual) prerequisites on the possibility of long-term following anti-atherosclerotic diets by coronary patients was investigated. Basing on the examination of the patients they were divided into three groups: those who strictly kept the diet (I), patients who moderately violated the diet (II), and those who did not keep the diet at home (III). Specific psychological methods used in the study allowed differentiation of these groups of patients. A conclusion has been made on the relation between the capacity for keeping the diet and some psychological personality traits of coronary patients. The analysis of the results enabled the authors to reveal a complex of problems for prognosing the coronary patients' readiness to keep the diet at home. The data obtained may be conductive to a rise in the medicosocial adaptation of coronary patients to long-term diet therapy by means of directed psychotherapy.  相似文献   
9.
Screening pure cultures of 65 mycolic acid producing bacteria (Mycolata) isolated mainly from activated sludge with a laboratory based foaming test revealed that not all foamed under the conditions used. However, for most, the data were generally consistent with the flotation theory as an explanation for foaming. Thus a stable foam required three components, air bubbles, surfactants and hydrophobic cells. With non-hydrophobic cells, an unstable foam was generated, and in the absence of surfactants, cells formed a greasy surface scum. Addition of surfactant converted a scumming population into one forming a stable foam. The ability to generate a foam depended on a threshold cell number, which varied between individual isolates and reduced markedly in the presence of surfactant. Consequently, the concept of a universal threshold applicable to all foaming Mycolata is not supported by these data. The role of surfactants in foaming is poorly understood, but evidence is presented for the first time that surfactin synthesised by Bacillus subtilis may be important.  相似文献   
10.
Fracture mechanics parameters (stress intensity factorK I and its critical valueK Ic , crack opening displacement, and the contourJ integral) are originally defined for static and quasistatic loading conditions. On the basis of theoretical background, standard test methods for the experimental determination of their specific values were developed. Structural integrity analysis requires the extension of application of these parameters to other types of loading. We propose new parameters for stress corrosion (stress corrosion cracking thresholdK 1sco ), for cyclic loading (stress intensity factor range ΔK and fatigue threshold ΔK th), and for creeping at elevated temperatures (C * andC t integrals). The structural integrity of welded structures is mainly affected by cracks in welded joints. We demonstrate the practical application of fracture mechanics parameters to the evaluation of structural integrity under the above-mentioned loading conditions. Faculty of Technology and Metallurgy, University of Belgrade, Yugoslavia. Faculty of Mechanical Engineering, University of Belgrade, Yugoslavia. Published in Fizyko-Khimichna Mekhanika Materialiv, Vol. 32, No. 2, pp. 107–118, March–April, 1996.  相似文献   
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