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1.
Purified protein derivative (PPD)-stimulated monocytes derived from Mycobacterium bovis-sensitized cattle significantly potentiated lymphocyte mitogenic responses to concanavalin A (conA), as measured by incorporation of [3H] thymidine into cellular DNA. Monocytes were cultured for 24 hours in the presence of PPD, washed thoroughly, and mixed with purified lymphocytes; various doses of conA were added to these cultures, and the cultures were incubated for 4 days and assayed for DNA synthesis. The lymphocyte mitogenic responses to suboptimal, buy not optimal, doses of conA were significantly enhanced by the presence of PPD-activated monocytes from M bovis-sensitized cattle. Treatment nonsensitized cattle with PPD did not result in any significant enhancement of conA-induced lymphocyte mitogenic responses at any dose of conA tested.  相似文献   

2.
Serial blood samples were obtained from 16 Standardbred foals from time of birth to postpartum day 28. Sera were obtained and analyzed for gamma-glutamyltransferase (GGT), aspartate transaminase, and immunoglobulin (Ig) G. Presuckle colostrum from the respective mares of these foals was analyzed for GGT activity. Mean serum aspartate transaminase activities were significantly increased above presuckle values by postpartum hour 48 (P less than 0.01) and increased gradually over the first 14 days. Mean serum IgG concentrations were significantly greater than presuckle values by 5 hours after foals first suckled (P less than 0.01) and remained significantly increased during the 28-day sampling period. Serum GGT activity did not differ significantly over the period sampled. The SD were large, since there was a large degree of interindividual variation. Serum GGT activity in the foals was significantly increased over that in the mares throughout the period of the study. The profile of serum GGT activity over time in each foal did not show a pattern of change. There was no postsuckle increase in serum GGT activity nor a correlation between serum GGT activities and IgG concentrations at 24 hours after foals first suckled. Evidence was not obtained to support a colostric source of GGT involved in the increase of serum GGT activity in foals. Serum GGT activity seems to be increased in foals due to endogenous sources.  相似文献   

3.
Colon from chickens, four weeks old, can best be maintained for 24 hours in a serum-free organ culture system using Trowell T8 medium-agar sheet at 25 degrees C. From physiological observations of DNA and protein synthesis it was found that the protein content of colonic explants did not change in up to 48 hours of culture while the DNA content did not change in up to 24 hours but decreased significantly to two thirds of the controls in 48 hours of culture. The organ culture system can be maintained satisfactorily for 24 hours.  相似文献   

4.
Explant cultures were set up, using articular cartilage obtained from metatarsophalangeal joints of 11 horses. Explants from 2 horses were used to determine culture conditions appropriate for tissue viability. The cartilage explants maintained steady-state metabolism of proteoglycans during a 13-day evaluation period. The metabolic response of equine articular cartilage to incubation with recombinant human interleukin 1 (0.01 to 100 ng/ml) was studied, using cartilage obtained from the remaining 9 horses, age of which ranged from 3 months to 20 years. Interleukin 1 induced a dose-dependent release of glycosaminoglycan from the matrix during a 3-day incubation period. It also caused dose-dependent inhibition of glycosaminoglycan synthesis during a 3-hour pulse-labeling period. Explants obtained from older horses were significantly (P < 0.05) less responsive to interleukin 1, with respect to synthesis and release of glycosaminoglycan.  相似文献   

5.
In a 12-day treatment schedule, 5 ponies were given orally a paste formulation of phenylbutazone (PBZ) and 5 matched ponies were given equivalent doses of a placebo paste. On day 12, a mild, nonimmune inflammatory reaction was induced subcutaneously in the neck of each pony by inserting sterile, polyester sponge strips soaked in a 2% carrageenan solution. Exudate was collected at 4, 8, 12, and 24 hours by serial removal of sponges. There were no significant (P less than 0.05) differences in exudate protein concentration and leukocyte numbers between the treatment groups, but the group given PBZ had significantly reduced exudate concentrations of eicosanoids 6-keto-prostaglandin F 1 alpha (the stable metabolite of prostacyclin) at 4, 8, and 12 hours; thromboxane B2 at 8, 12, and 24 hours; and bicyclic prostaglandin E2 at 8 hours. The maximal depression of eicosanoid synthesis occurred at times of peak exudate concentrations of PBZ (8 and 12 hours). Phenylbutazone was cleared more slowly from exudate than from plasma. Changes in surface skin temperature were measured by infrared thermometry. Lesional temperatures were recorded 1 cm below the base of the incision line, and mean increases were significantly (P less than 0.05) less in PBZ-treated than in placebo-treated ponies between 4 and 24 hours. The importance of the findings for the clinical efficacy of this dosage schedule is considered.  相似文献   

6.
OBJECTIVES: To determine the ionised calcium concentration following aerobic collection of blood and to compare ionised calcium concentration and pH of heparinised whole blood and plasma at 48 hours following collection under three different storage conditions to assess if ionised calcium concentration can be measured retrospectively. METHODS: Blood was collected from 17 dogs for analysis of ionised calcium concentration and pH using a Rapidpoint 400 (Bayer) blood gas analyser. Blood was collected into a commercial preheparinised syringe and into a plain syringe, with subsequent transfer to a commercially available heparinised sample tube. Samples were analysed within 10 minutes, and the remainder was divided for storage. One aliquot was set-aside at room temperature for 48 hours, and the other was immediately centrifuged and the plasma divided for storage at room temperature and at 4 degrees C for 48 hours each. In all samples, ionised calcium concentration and pH were measured again at 48 hours after storage. RESULTS: There was no significant difference in ionised calcium concentration or pH between anaerobically and aerobically collected heparinised whole blood analysed within 10 minutes of collection. At 48 hours, ionised calcium concentrations had decreased under all storage conditions irrespective of the direction of pH change. CLINICAL SIGNIFICANCE: Ionised calcium concentration can be measured in aerobically collected samples within 10 minutes and at 48 hours after collection under the conditions described.  相似文献   

7.
Three main factors underlying the immunity state of newborn calves are evaluated. During the absorption of colostral immunoglobulins the immunoprotein profile of a newborn calf is influenced by the following factors (arranged according to importance): volume of the first colostrum taken in, time of the first drinking, and immunoglobulin concentration (IgG and IgM) in colostrum. When given 1.1 or 2.0 litres of colostrum of about the same quality (as to immunity), the calves of the compared groups had significantly different levels of total serum Ig measured 24 hours after birth: 10.7 and 18.6 U ZST (P less than 0.05) and 48 hours after birth: 11.7 and 19.7 U ZST (P less than 0.01). A significant difference in total serum proteins was observed only in the 48th hour post partum (54.4 and 63.6 g per litre; P less than 0.05). At the intake of 1.5 litres of colostrum within two and five hours after birth, with the same total intake of the sum of IgG and IgM in the groups, the calves exhibited, in the 24th hour, total serum Ig levels of 14.4 and 12.4 U ZST (P greater than 0.05) respectively, and 56.0 and 47.9 g per litre (P greater than 0.05) of total serum protein, respectively. With a different concentration of colostral IgG (122.0 or 77.0 g per litre) the statistically significant Ig absorption into blood was adequately different (17.2 and 10.0 U ZST, respectively, P less than 0.05). The differences in the concentration of total serum Ig and total proteins between the 24th and 48th hour after birth were only very small and statistically insignificant. Regression analysis proved a significant relation (P less than 0.01) between the level of total serum Ig 24 and 48 hours after birth and the total amount of IgG and IgM taken in with the first colostrum. The calves coming from primiparae had a lower immunity (P less than 0.01) in comparison with the calves of multiparae. A similar relation in the absorption of colostral Ig was observed when the spontaneously born calves were compared with those born by the Caesarean section (P less than 0.01).  相似文献   

8.
SUMMARY Eighty-five unsuckled newborn calves, were fed 1.5 L of colostrum of known IgG concentration at either 2, 4, 6 or 8 hours after birth with no additional colostrum feeding. Another group of 11 calves were left with their dam for 16 hours after birth, before separation. Blood samples were taken from all calves 24 hours after colostrum feeding or separation from the dam and serum Ig concentrations were measured by electrophoresis. There were no significant differences in mean serum Ig concentrations between calves fed at the different times after birth. Three of the 11 calves left to suckle were hypogamma-globulinaemic. Other calves in this group had higher serum Ig concentrations than the means of all other groups. All groups had mean serum Ig concentrations higher than the suggested minimum concentration required for adequate calf health. There were a number of calves that did not reach the suggested minimum serum concentration after feeding, but calf mortality was low and all calves were healthy apart from a slight scour for a few weeks after birth. There was no significant relationship between serum Ig concentration 24 to 48 hours after birth and either calf mortality or average growth rate over an 8- to 10-month period.  相似文献   

9.
OBJECTIVE: To evaluate effect of alternate-day oral administration of prednisolone on endogenous plasma ACTH concentration and adrenocortical response to exogenous ACTH in dogs. ANIMALS: 12 Beagles. PROCEDURE: Dogs were allotted to 2 groups (group 1, 8 dogs treated with 1 mg of prednisolone/kg of body weight; group 2, 4 dogs given excipient only). During a 30-day period, blood samples were collected for determination of plasma ACTH and cortisol concentrations before, during, and after treatment with prednisolone. From day 7 to 23, prednisolone or excipient was given on alternate days. Sample collection (48-hour period with 6-hour intervals) was performed on days 1, 7, 15, 21, and 28; on other days, sample collection was performed at 24-hour intervals. Pre- and post-ACTH plasma cortisol concentrations were determined on days 3, 9, 17, 23, and 30. RESULTS: A significant difference was detected between treatment and time for group 1. Plasma ACTH concentrations significantly decreased for 18 to 24 hours after prednisolone treatment in group-1 dogs. At 24 to 48 hours, ACTH concentrations were numerically higher but not significantly different in group-1 dogs. Post-ACTH plasma cortisol concentration significantly decreased after 1 dose of prednisolone and became more profound during the treatment period. However, post-ACTH cortisol concentration returned to the reference range 1 week after prednisolone administration was discontinued. CONCLUSIONS AND CLINICAL RELEVANCE: Single oral administration of 1 mg of prednisolone/kg significantly suppressed plasma ACTH concentration in dogs for 18 to 24 hours after treatment. Alternate-day treatment did not prevent suppression, as documented by the response to ACTH.  相似文献   

10.
Transfection of chicken embryo fibroblasts with Marek's disease virus DNA   总被引：11，自引：0，他引：11  
Total DNA from Marek's disease virus (MDV)-infected chicken embryo fibroblasts was transfected into freshly plated secondary chicken embryo fibroblasts using calcium phosphate-mediated transfection. Transfection frequencies were dose-dependent and non-linear. The maximum transfection frequencies of nine MDV DNA preparations using 8-25 micrograms total DNA ranged from 45 to 898 plaques per calcium phosphate/DNA precipitate. Approximately 100-200 plaques per 60-mm tissue-culture dish using 1-5 micrograms total DNA from MDV-infected chicken embryo fibroblasts were typically obtained. Transfection was most efficient when the pH of the HEPES buffer was 7.0, no additional carrier DNA was added to the precipitates, and the cultures were exposed for 3 minutes to 15% buffered glycerol 4 hours after the addition of the calcium phosphate/DNA precipitates.  相似文献   

11.
A study was performed to determine the effect of proadifen hydrochloride on prostacyclin (prostaglandin I2 [PGI2]) and thromboxane A2 (TxA2) synthesis by equine peritoneal macrophages and the effect of proadifen on endotoxin-induced synthesis of PGI2 and TxA2 by equine macrophages. Peritoneal macrophages (2.5 x 10(6)/ml) were incubated for 6 hours in tissue culture media containing 1) nothing (nontreated control), 2) proadifen hydrochloride (20, 100, 250, and 500 mumol/L, 3) endotoxin (5 ng/ml), or 4) the calcium ionophore A23187 (0.95 mumol/L). In a second series of experiments, peritoneal macrophages were incubated with endotoxin (5 ng/ml) and proadifen (250 umol/L), for 6 hours. Concentrations of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) and thromboxane B2, the stable metabolites of PGI2 and TxA2, were determined in the incubation media by radioimmunoassay. Proadifen caused increased synthesis of PGI2 by equine macrophages, without affecting TxA2 production. The increased PGI2 production was similar to that induced by endotoxin and calcium ionophore; however, the latter 2 agents significantly stimulated TxA2 production as well (P less than 0.05). There were no significant differences among mean concentrations of 6-keto-PGF1 alpha in media from macrophages treated with 100, 250, or 500 mumol/L proadifen, but there was a significant curvilinear regression between their concentrations. The ratio of thromboxane B2 to 6-keto-PGF1 alpha was significantly lower than baseline in incubation media from macrophages exposed to proadifen, endotoxin, and calcium ionophore. Proadifen hydrochloride did not significantly change equine peritoneal macrophage production of PGI2 or TxA2 in response to endotoxin.  相似文献   

12.
OBJECTIVE: To evaluate flow cytometric analysis for sex identification in 3 psittacine species, establish reference values for blood cell DNA content for each species, and determine effects of sample storage on DNA content. ANIMALS: 36 orange-winged Amazon parrots, 41 budgerigars, and 39 cockatiels. PROCEDURE: Blood samples were stained and analyzed by use of flow cytometry to measure cellular DNA content. Samples were analyzed immediately after collection and after being stored at 4 C for 48 and 72 hours. RESULTS: Mean DNA content (picograms per cell) was 3.248 for Amazon parrots, 2.702 for budgerigars, and 2.946 for cockatiels; DNA concentrations in samples analyzed immediately overlapped in a male and a female Amazon parrot and among 19 cockatiels. For budgerigars, DNA overlap between sexes was not detected in samples analyzed immediately or after storage for 72 hours. Sex was identified correctly in 94.4% of Amazon parrots, 100% of budgerigars, and 51.3% of cockatiels. For both sexes, DNA content in samples analyzed immediately was significantly different from that of stored samples. CONCLUSIONS AND CLINICAL RELEVANCE: Flow cytometric analysis was accurate for sex identification of Amazon parrots and budgerigars. Sample storage at 4 C for 48 or 72 hours caused variability in DNA content.  相似文献   

13.
OBJECTIVE: To evaluate the origin and degree of activity of nitric oxide (NO) and matrix metalloproteinase (MMP) in explants of cranial cruciate ligaments (CCLs) obtained from dogs and cultured with and without inflammatory activators. SAMPLE POPULATION: Tissue specimens obtained from 7 healthy adult Beagles that were (mean +/- SD) 4.5 +/- 0.5 years old and weighed 12.5 +/- 0.8 kg. PROCEDURE: The CCLs were harvested immediately after dogs were euthanatized, and specimens were submitted for explant culture. Cultures were stimulated by incubation with a combination of interleukin-1, tumor necrosis factor-alpha, and lipopolysaccharide, or they were not stimulated. Culture supernatants were examined for production of NO nitrite-nitrate metabolites (NOts) and activity of MMP Cultured specimens were evaluated by use of immunohistochemical analysis to detect activity of inducible NO synthase (iNOS). RESULTS: All ligament explants produced measurable amounts of NOts. Stimulated cultures produced significantly more NOts after incubation for 24 and 48 hours, compared with nonstimulated cultures. Production of MMP in supernatants after incubation for 48 hours was significantly higher in stimulated cultures than in nonstimulated cultures. Cells with positive staining for iNOS were detected on all slides. Positively stained cells were predominantly chondroid metaplastic. There was a significant difference in intensity of cell staining between stimulated and non-stimulated cultures. CONCLUSIONS AND CLINICAL RELEVANCE: Explant cultures of intact CCLs obtained from dogs produce iNOS-induced NO. Stimulation of chondroid metaplastic cells in CCL of dogs by use of inflammatory activators can increase production of iNOS, NOts, and MMP.  相似文献   

14.
The stability of serum ionized calcium concentration (ICa) from dairy cows was studied after anaerobic collection and frozen storage. Paired blood samples were obtained from five groups of cows: nonlactating, first third of lactation, midlactation, last third of lactation, and 2-year-old nonlactating heifers. Vacutainer multiple sample needles and serum separator tubes (SST) were used for venipuncture. Aspiration of serum was within 1.5 hours after collection: one sample for immediate determination (within 2 hours of collection); the other sample stored at -4 degrees C in evacuated plastic vacutainer tubes filled with serum to provide dead space of less than 75% of volume, and analyzed after 14 to 30 days in storage (half, 15, of the samples from each lactation group were analyzed after frozen anaerobic storage at 14 or 30 days, respectively). Processing samples in this manner significantly altered the values obtained for ICa, normalized calcium concentration (NCa), and pH. Analysis after frozen storage in evacuated tubes caused ICa and NCa concentrations to decrease and pH to increase (P< 0.05); total calcium levels were not significantly different from initial values. There were no significant differences among lactation groups. The difference between values obtained from these paired samples was either due to loss of CO(2) during transfer from the SST to the evacuated tube or during frozen storage. Changes in samples assayed after freezing and storage could be adjusted to original values by using the mean difference between the fresh and frozen levels as correction factors: ICa (+0.4379), NCa (+0.2797), and pH (-0.0926). It was concluded that immediate determination of serum ICa in dairy cattle is the ideal but using this methodology and performing analyses later may be acceptable if correction factors are determined.  相似文献   

15.
The present study involves the use of RAPD-PCR to evaluate the genotoxic effects of furadan in the DNA of Labeo rohita (rohu) fingerlings. Rohu fingerlings were exposed to 0.02 ppm of furadan for a total period of 96 h and samplings were done at 24, 48, 72 and 96 h. RAPD - PCR were carried out with the blood and liver DNA samples of both control and treated groups at each of the four sampling hours. A total of six selected RAPD primers were used for PCR amplification. Template stability has been taken as the measure of DNA damage caused by pesticide. The results obtained showed no significant difference in the template stability in the blood DNA of furadan treated groups at any of the four sampling hours; however, the liver DNA were able to show significant difference at 48 and 96 hours of treatment.  相似文献   

16.
Virus synthesis in BALB/C mouse lung and kidney primary cultures infected with infectious bovine rhinotracheitis (IBR) virus started between 6 and 8 hours after virus inoculation and reached a maximum titer of 5.5 log10 plaque forming units (PFU) at 48 hours postinfection (PI). Cytopathic effect (CPE) in cell cultures occurred at 8–10 hours and over 90% of the cells had CPE by 48 to 72 hours PI. The bulk of the newly replicated virus (60–80%) was cell-associated as determined by plaque assay of extracellular and intracellular virus. Pulse-chase experiments demonstrated incorporation of radioactive precursors into viral DNA and protein macromolecules. Viral DNA synthesis was initiated between 2 and 4 hours PI and was maximum at 4 to 6 hours. Viral proteins were detected at 4 hours and peaked between 6 and 8 hours PI. Enzyme-linked immunosorbant assay (ELISA) confirmed synthesis of specific viral proteins, which gradually increased during the virus growth cycle. Abstract in French is given at the end of the article.
Resume La synthèse du virus de la rhinotrachéite infectieuse bovine (virus IBR) sur des cultures primaires de poumon et de reins de souris (souche Balb/C) commençait entre 6 et 8 heures après inoculation du virus et atteignait un titre maximal de 5.5 log PFU (Plaque Forming Unit) 48 heures après infection. L'effet cytopathogenic (CPE) sur ces cultures cellulaires apparaissaient en 8 à 10 heures et plus de 90% des cellules montraient un CPE en 48 à 72 heures après infection. La détermination par la méthode des plages sous agarose, du virus extracellulaire et du virus intracellulaire, indiquait que 60–80% du virus synthétisé était associé avec les cellules. Les expériences de pulsechase demontraient l'incorporation des précurseurs radioactifs dans les protèines et ADN viraux. La synthèse virale d'ADN était initiée entre 2 et 4 heures après infection et était maximale en 4 à 6 heures. Les protéines virales étaient détectées en 4 heures avec un maximum de synthèse entre 6 et 8 heures après infection. Enzyme-linked immunosorbant assay (ELISA) confirmait la synthèse de protéines virales spécifiques qui montrait une augmentation graduelle pendant le cycle de replication du virus.

Supported in part by grants 0831 from the Cooperative State Research Service of the US Department of Agriculture and published as contribution 85-160-J, Kansas Agricultural Experiment Station.  相似文献   

17.
Gastric myoelectric activity was measured after experimental gastric dilatation-volvulus (GDV), GDV and tube gastrostomy, or tube gastrostomy in 12 dogs. Gastric myoelectric activity was recorded for 1 hour before (hour 0) and at hours 5, 24, 48, 72, and 96 after surgically induced GDV in six dogs. Three dogs with induced GDV and tube gastrostomy, and three dogs with tube gastrostomy only were also studied at hours 120, 144, and 168. The only significant change in the slow wave appearance or frequency from hours 0 to 48 was bradygastria at hour 5 in all three groups. A relative increase in the mean percentages of dysrhythmia from hours 72 to 168 in the dogs with a tube gastrostomy was caused by increases in tachygastria and arrhythmias. Dogs with GDV and tube gastrostomy had the greatest mean percentages of dysrhythmia, which were significantly more than those in dogs with GDV alone at hours 48, 72 and 96. The mean percentage of spike activity was less than or equal to 31 and varied widely. In general, there was less spike activity when the frequency of dysrhythmias was high. Thus, gastric myoelectric activity was disrupted from hours 48 to 168 after GDV with tube gastrostomy and after tube gastrostomy alone. Surgically induced GDV alone did not produce any significant or sustained dysrhythmias.  相似文献   

18.
The goal of the present study was to evaluate a calcium dose that was higher than the conventional dose for treatment of parturient paresis in cows. Thirty cows with parturient paresis received 1000 ml of 40 per cent calcium borogluconate solution supplemented with 6 per cent magnesium hypophosphite. Cows in group A received 200 ml of the solution intravenously over a 10-minute period, and the remaining 800 ml via a slow intravenous drip over a six-hour period. Cows in group B received 500 ml of the solution intravenously over a 20-minute period, and the remaining 500 ml via a slow intravenous drip over a six-hour period. Afterwards, the cows were monitored continuously and examined every hour for eight hours. Samples of blood were collected from all the cows before treatment and at 10, 20, 40, 60, 90, 120, 180, 240, 300, 360, 420 and 480 minutes and 24, 48 and 72 hours after treatment. The concentrations of total calcium, ionised calcium, inorganic phosphorus and magnesium were determined. Cows that did not stand within 12 hours of treatment received one or more additional treatments. There was no significant difference in the recovery rate between the two groups. Of the 30 cows, 14 (47 per cent) rised after one treatment and 15 others (50 per cent) were cured after two or more treatments. One cow did not respond to repeated treatments and was euthanased four days after the start of treatment. The results of electrolyte analyses before treatment did not differ significantly between the two groups. In 27 (90 per cent) cows, the concentrations of calcium and inorganic phosphorus were lower than normal and in 3 (10 per cent) cows, only the concentration of inorganic phosphorus was lower than normal.The concentration of total calcium increased markedly ten minutes after the start of treatment in both groups, and at eight hours, the mean concentration of calcium was within the normal range. At 24 and 48 hours, the mean concentration of calcium was below normal, but at 72 hours it was again within the normal range. The concentration of inorganic phosphorus increased slowly in both groups, although it was not within the normal range at eight hours. In both groups, it achieved normal values at 24, 48 and 72 hours.The mean electrolyte concentrations did not differ significantly at any measuring point between cows that stood within eight hours of treatment and those that did not. Our results indicate that increasing the dose of calcium administered does not improve the recovery rate of cows with parturient paresis.  相似文献   

19.
本试验旨在研究试验鸡不同季节、不同批次间内源总能的变异及其对饲料原料真代谢能值的影响。试验采用单因素完全随机设计,分春季、夏季和秋季3个季节共计12个批次测定鸡内源总能及其对饲料原料[玉米、玉米干酒糟及其可溶物(DDGS)、木薯干和木薯渣]真代谢能值的影响,每个批次设4个重复,每个重复3只鸡。将各季节内各批次内源总能的平均值作为该季节内源总能,并根据不同季节的内源总能分别计算其对4种饲料原料真代谢能值的影响。结果表明:1)12个测定批次间48 h内源总能差异显著(P0.05),但3个季节内48 h内源总能差异均不显著(P0.05),因此,可将测定季节内各个批次间48 h内源总能数据合并,将其平均值作为该季48 h内源总能。2)对比3个季节间的48 h内源总能,秋季48 h内源总能(67.97 k J/只)极显著低于春季(83.07 k J/只)和夏季(79.90 k J/只)(P0.01),但春季和夏季间48 h内源总能差异不显著(P0.05)。3)季节内48 h内源总能与48 h内源干物质排泄量呈极显著正相关(r≥0.91,P0.01)。4)在玉米、玉米DDGS、木薯干及木薯渣4种饲料原料中,不同季节48 h内源总能的最大变化量分别占饲料总能排泄量的7.36%~8.38%、2.68%~2.94%、7.92%~10.86%和3.53%~3.96%,不同季节48 h内源总能的变异引起饲料原料真代谢能值的变化范围为0.28~0.36 k J/g。由此可见,鸡内源总能在季节间存在一定的变异,但是该变异对饲料原料真代谢能值的计算并无显著影响。  相似文献   

20.
Equol, an isoflavonoid metabolite produced from the dietary isoflavone daidzein by the gut microflora in mammals, has been found to protect not only against ultraviolet (UV) radiation-induced cutaneous inflammation and photoimmune suppression, but also have anti-photocarcinogenic properties in mice. Because the state of DNA damage has been correlated with suppression of the immune system and photocarcinogenesis, we have therefore examined the potential of equol to offer protection from solar-simulated UV (SSUV) radiation-induced DNA damage in hairless mice by the immunohistochemical approach using monoclonal antibody specific for cyclobutane pyrimidine dimers (CPDs; H3 antibody). Topical application of 20 µM equol lotion, which was applied both before and after SSUV significantly reduced the number of CPDs. This reduction was evident immediately after SSUV exposure, at 1 h after exposure, and at 24 h after exposure, revealing 54%, 50%, and 26% reduction in CPDs, respectively. When the same concentration was applied for 5 consecutive days after SSUV exposure, there was no significant difference in the reduction of CPDs immediately after SSUV irradiation or at 1 hour afterwards, but there were significant reductions of 23% and 42% at 24 and 48 h after SSUV exposure, respectively. Despite apparently reducing the number of CPDs post-SSUV, topically applied equol did not appear to increase the rate of dimer removal. To conclude, equol applied topically prior to SSUV irradiation offers protection against CPD formation in hairless mice, possibly by acting as a suncreen and thus inhibiting DNA photodamage.  相似文献   

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