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1.
The acid detergent lignin and Klason lignin methods were compared for their correlation with forage digestibility. Thirty-six forages, including C3 legumes and C3 and C4 grasses, were analyzed for sulfuric acid detergent lignin, Klason lignin, and in vitro digestibilities of dry matter (DM) and neutral detergent fiber (NDF). Twenty of these forages were also fed to lambs at restricted intake for measurement of DM and NDF digestibilities. Lignin concentrations determined by the two lignin methods were positively correlated, and the Klason lignin value was always greater than the acid detergent lignin concentration. The largest differences were observed for grass forages. Digestibilities of forage DM and NDF were negatively correlated with both lignin methods for the in vitro system and the lamb digestibility trials. The degree of correlation for the two lignin methods with digestibility was generally similar across all forages and within forage classes. Slopes of linear regressions of digestibility on lignin concentration did not differ between legumes and grasses. Although the sulfuric acid detergent lignin and Klason lignin procedures gave very different estimates of forage lignin concentration, they were similarly correlated with digestibility and should yield predictions of forage digestibility that have similar accuracy.  相似文献   

2.
In this study we have shown that an antibody to CD18 identified a population of cells in the rabbit retina that resembled the perivascular macrophage found in other regions of the central nervous system. In the normal retina these cells possessed a ramified morphology and presented in an ordered array on the vitreal surface in association with the epiretinal vessels. Approximately 50% of the perivascular macrophages constitutively expressed MHC class II. In response to interleukin-1 beta (IL-1 beta)-induced inflammation, these cells became activated, as evidenced by a change from a ramified to an ameboid morphology and increased expression of MHC class II, and migrated away from the vessels. These changes were first detected around 3 h post-intraocular challenge coincident with the onset of inflammation. At the peak of the inflammatory response (approximately 24 h post-challenge), many activated perivascular macrophages were no longer associated with the vessels and formed long "cord" of MHC class II+ cells associated with underlying deposits of fibrin. In eyes challenged with heat-inactivated IL-1, no change in the morphology or distribution of the perivascular macrophage was noted. At 3 weeks post-challenge with IL-1, the number and distribution of the perivascular macrophages were restored to baseline values, although with a reduced cell size. Since these changes closely resemble those that occur in non-lymphoid dendritic cells in the skin, heart, and/or kidney following activation with cytokines or bacterial products, the results suggest that the perivascular macrophage represents the dendritic cell of the retina and may thus play an important role in immune surveillance in the eye and maintenance of the blood-retina barrier.  相似文献   

3.
In 2 experiments lasting 30 days each with participation of 6 volunteers the possibility of daily consumption in the diet of chufa in an amount allowing for minimal requirement of the organism in polyunsaturated fatty acids was studied. The experimental food ration accorded with individual requirements in its basic components. None of the participating volunteers demonstrated any untoward deviations of objective and subjective nature in their health status. For a month chufa was introduced daily at the rate of 1.7 g per kg of body weight.  相似文献   

4.
Following axotomy most medial septal neurons in the adult rat brain have dramatically reduced numbers of choline acetyltransferase (ChAT) positive neurons. Since leukemia inhibitory factor (LIF) promotes cholinergic expression in several neuronal populations, the aim of this study was to determine if LIF would continue to support cholinergic expression in axotomized medial septal neurons. Mini-osmotic pumps were used to infuse saline or LIF into the lateral cerebral ventricle. Counts of ChAT and low-affinity nerve growth factor (p75NGFR) immunostained neurons indicated that LIF-treated animals retained ChAT expression in > 90% of axotomized neurons whereas in saline-infused animals this was < 30%. Also, LIF was equally effective in maintaining p75NGFR expression levels in axotomized medial septal neurons.  相似文献   

5.
6.
Rice straw was fermented with Cellulomonas sp. and Alcaligenes faecalis. Microbial cells and undigested residue, as well as chemically treated (NaOH or NH4OH) and untreated straws, were analyzed for nutrient composition and in vitro digestibility. In a typical fermentation, 75% of the rice straw substrate was digested, and 18.6% of the total substrate weight that disappeared was recovered as microbial protein. The microbial cell fraction was 37% protein and 5% crude fiber; the residue was 12% protein and 45% crude fiber. The microbial protein amino acid profile was similar to alfalfa, except for less cysteins. The microbial cells had more thiamine and less niacin than Torula yeast. In vitro digestibility of the microbial protein was 41.2 to 55%, that of cellulose was 52%.  相似文献   

7.
The inflammatory arthropathies that affect the eye most commonly are RA, JRA, and the seronegative spondyloarthropathies. These conditions not only cause devastating systemic findings but can be the source of damaging ocular disease. The inflammatory nature of these entities, with the accompanying liberation of mediators of inflammation, can result in a cycle of tissue destruction that culminates in blindness. The diseases reviewed can present first with systemic or ocular findings; thus, all physicians must be equipped with the appropriate knowledge to make accurate and timely diagnoses so that appropriate management strategies can be employed. The successful recognition and treatment of these conditions can prevent their associated systemic and ocular morbidity.  相似文献   

8.
Tested the hypothesis that individuals would infer less extreme attitudes from the nonoccurrence of a behavior than from the occurrence of a behavior. 52 Ss rated cartoons for humor or lack of humor under 4 conditions: 2 similar responses, 2 different types of response, response to humorous cartoon, and response to nonhumorous cartoon. Results confirm the prediction. Relevant investigations from the self-perception literature are discussed in light of this feature-positive effect. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
Previous research showed that treatment with conjugated linoleic acid (CLA) during the period of active mammary gland morphogenesis was sufficient to confer a lasting protection against subsequent mammary tumorigenesis induced by methylnitrosourea. The present study was designed to characterize certain morphological and biochemical changes of the mammary gland that might potentially render it less susceptible to cancer induction. Female Sprague Dawley rats were fed a 1% CLA diet from weaning until about 50 days of age. The mammary gland parameters under investigation included (a) the deposition of neutral lipid, (b) the identification and quantification of CLA and its metabolites, (c) the density of the epithelium, and (d) the proliferative activity of various structural components. Our results showed that CLA treatment did not affect total fat deposition in the mammary tissue nor the extent of epithelial invasion into the surrounding fat pad but was able to cause a 20% reduction in the density of the ductal-lobular tree as determined by digitized image analysis of the whole mounts. This was accompanied by a suppression of bromodeoxyuridine labeling in the terminal end buds and lobuloalveolar buds. The recovery of desaturation and elongation products of CLA in the mammary gland confirmed our prior suggestion that the metabolism of CLA might be critical to risk modulation. The significance of the above findings was investigated in a mammary carcinogenesis bioassay with the use of the dimethylbenz[a]anthracene model. When CLA was started at weaning and continued for 6 months until the end of the experiment, this schedule of supplementation produced essentially the same magnitude of mammary tumor inhibition in the dimethylbenz[a]anthracene model as that produced by 1 month of CLA feeding from weaning. The observation is consistent with the hypothesis that exposure to CLA during the time of mammary gland maturation may modify the developmental potential of a subset of target cells that are normally susceptible to carcinogen-induced transformation.  相似文献   

10.
The effect on milk yield and composition of the supplementation of the diets of dairy cows with wheat or potato peelings was studied at three different starch intakes (< 5, 6, and > 7.5 kg/d) for dry matter intakes around 20 kg/d. Starch supply was varied using different dietary concentrations of corn silage. Trials were conducted using Latin square designs, and all cows were fed a total mixed diet composed of corn silage, grass silage, or both; soybean meal; a mixed meal with formaldehyde treatment; minerals; and one of the following energy concentrates: potato peelings or wheat. Dry matter and energy intakes varied significantly only at the low starch concentration; higher intakes were observed when the potato peelings were fed. Body weight, milk yield, true protein content, lactose content, and protein yield were not affected by treatment. Milk fat content was higher (+3.3 g/kg) when potato peelings were fed at the high starch concentration but was unaffected at the low and medium starch concentration. Slow degradation of starch from the potato peelings in the rumen could enhance a higher delivery of precursors of milk fat synthesis in the udder. The effect on fat yield differed among starch concentrations. Milk fat content appeared to decrease for cows fed diets containing quickly degradable starch at a starch intake > 7 kg/d.  相似文献   

11.
Gastric fistula rats (n = 79) were either left as unstressed (fistula closed) controls or gastric secretion, microcirculation (MBF), mucosal stress ulcers were studied in secretory rats subjected to zero (= freely movements allowed), mild, severe restraint stress for 8 h. In all rats gastrin in portal vein and aorta was measured in addition after discontinuation of either protocol. Acid secretion and MBF are progressively reduced by increasing stress. Pepsin and sodium are elevated with severe, acid concentration with mild stress. Pepsin and sodium are elevated with severe, acid concentration with mild stress. Serum gastrin (controls - aorta 53+/- SEM 5, portal vein 73 +/- 9 pg/ml) rises sharply in portal and systemic blood with institution of acid diversion via the outside (zero stress - 136 +/- 21, 398 +/- 98 pg/ml), but declines with increasing stress (severe stress - 82 +/- 16, 101 +/- 27 pg/ml) despite otherwise identical experimental conditions. It is concluded that (1) acid secretion rate and MBF are lowered by stress, but stress ulcers are associated with either increased acidity (mild stress) or peptic activity (severe stress) of gastric juice in the absence of elevated gastrin, (2) enhanced sodium fluxes via gastric lumen and lower acid suggest disruption if mucosal barrier by severe stress, and (3) restraint stress ulcers may be the expression of a combination of disturbances, mainly of metabolic and endocrine nature.  相似文献   

12.
The in vitro maturation rate of equine oocytes remains low, regardless of culture conditions. Our objective was to determine the reasons for failure of equine oocytes to resume meiosis during in vitro maturation and to ascertain the influence of the estrous cycle stage on meiotic competence. In 10 cyclic mares, 7 ultrasound-guided follicular punctures were performed alternately during the follicular phase (group DF; n = 3 punctures), at the end of the follicular phase (group EF; n = 2), and during the luteal phase (group DL; n = 2). We evaluated the competence of the oocytes for in vitro maturation and measured their maturation-promoting factor activity by histone H1 kinase assay. Puncturing once at the end of the follicular phase and once during the luteal phase, or three times during the follicular phase, yielded about 11 cumulus-oocyte complexes per 22 days. The maturation rate was different between the groups, 51% in group EF, 34% in group DL (p < 0.05), and 15% in group DF (p < 0.01), and it increased with an increase in follicular diameter (p < 0.05). After in vitro culture, the H1 kinase activity was lower in oocytes that remained in germinal vesicle or dense chromatin stages than in oocytes that reached metaphase I or metaphase II (p < 0.05). The H1 kinase activity was not different between oocytes in germinal vesicle stage after in vitro maturation and immature oocytes that were not cultured in vitro, and was higher in preovulatory oocytes that reached metaphase II in vivo than in the oocytes that reached metaphase II after in vitro maturation (p < 0.001). This is the first report on kinase activity in the equine oocyte.  相似文献   

13.
Supplementation of children diet with food enriched by vitamins, antioxidants and dietary fiber food (beverage 'Zolotoy shar', bread with addition of bran, 'doctorskije' rolls inhibited or normalized the lipid peroxidation of cell membranes, methemoglobin production and increased some indices of humoral immunity. The results allow to recommend the studied special food for prophylactic use for children dietary intake in regions of ecological pollution.  相似文献   

14.
CD23 has been reported to be a macrophage/monocyte activation antigen. We focused on the expression of CD23 by peripheral blood macrophages/monocytes in 5 Kawasaki disease (KD) patients with coronary artery lesions (CAL) and compared these values with those of 35 patients without CAL. The expression of CD23 on peripheral blood macrophages/monocytes was assayed by a fluorescence-activated cell sorter using monoclonal antibodies CD23 and CD14. Absolute counts of CD23+CD14+ macrophages/monocytes in KD patients with CAL did not increase during the acute stage, while these values in KD patients without CAL increased. In addition, this decreased expression of CD23 on peripheral blood macrophages/monocytes in patients with CAL did not change during the acute stage, regardless of IVGG therapy. Our results suggest that the decreased expression of CD23 on peripheral blood macrophages/monocytes in patients with CAL is part of the regulatory system of CD23 antigen during acute KD.  相似文献   

15.
16.
A new minimal medium consisting only of L-tryptophan (L-Trp) and a lipid source induced formation of brown pigmentation only in the species Malassezia furfur, which diffuses into the agar. Strains of the species M. sympodialis and M. pachydermatis failed to grow on this medium. On mDixon medium, however, after replacement of peptone by L-Trp, growth of all three Malassezia species was achieved. Under these conditions pigment production was observed with all M. furfur strains tested, although the results for M. pachydermatis strains were inconsistent. M. sympodialis strains showed no pigment production. On the minimal medium pigmentogenesis was induced in M. furfur by only 0.01 g% tryptophan; the pH optimum was pH 5. In all M. furfur strains, alternative amino nitrogen sources given concurrently with Trp suppressed pigmentogenesis. Furthermore, there were differences in the optimal temperature among the individual M. furfur strains. CBS 7019, CBS 6000 and CBS 6001 failed to produce pigment at 37 degrees C. The extract of the culture exhibited remarkable fluorescence, and several indole derivatives with a broad spectrum of colours were detected. This finding may have an impact on the clinical appearance of pityriasis versicolor, a very common skin disease caused by lipophilic yeasts of the genus Malassezia. We hypothesize that in pityriasis versicolor metabolic adaptation of Malassezia yeasts to altered nitrogen conditions on superficial skin might be of patho-physiological importance. Tryptophan as an inducer of pigmentogenesis probably accumulates during excessive sweating, a well-known manifestation of pityriasis versicolor.  相似文献   

17.
Contents of bile acids and lipids, as well as rates of triglyceride synthesis, were determined in isolated hepatocytes from control or cholestyramine-fed rats (denoted below as "control" or "treated" hepatocytes, respectively). During a 3-hr incubation period, total bile acid production was markedly higher in "treated" cells than in "control" cells. With both kinds of cells a marked fall in production rate occurred after the first hour of incubation. Newly produced bile acids appeared in the conjugated form with both kinds of hepatocytes. "Control" cells produced only taurine-conjugated, while "treated" cells made both taurine-conjugated and glycine-conjugated bile acids. However, with exogenous taurine (0.5 mM), the latter cells also produced taurine-conjugated bile acids only. With both kinds of cells, cholic and beta-muricholic acids, but not dihydroxylated bile acids, appeared as newly formed species during the incubation. Addition of dialyzed rat serum to the incubation did not result in a stimulation of bile acid production, with either kind of hepatocytes. "Treated" cells had a slightly higher content of free cholesterol than control cells; contents of other lipids were not different. Fractional release of bile acids and lipids into the medium did not differ between the two kinds of cells. Triglyceride synthesis from added [14C]palmitate (0.5 mM) was 1.8-fold higher in "treated" than in "control" hepatocytes.  相似文献   

18.
The evoked expression of the immediate-early gene-encoded proteins c-Fos and Krox-24 was used to study activation of mesodiencephalic structures as a function of the development of cyclophosphamide (CP) cystitis in behaving rats. This article is the third of a series and completes previously published data obtained at both spinal and hindbrain levels. CP-injected animals received a single dose of 100 mg/kg i.p. under transient volatile anesthesia and survived for 1-4 h in order to cover the entire postinjection period during which the disease develops. Survival times longer than 4 h were not used owing to ethical considerations. Results from CP-injected groups are compared with those from either noninjected controls or saline-injected animals having survived for the same times as CP-injected ones. Quantitative results come from c-fos expression. At mesodiencephalic levels a high and widespread basal c-fos expression was observed in control animals; maximum staining was observed at the midthalamic level. Four groups of nuclei were identified with regard to the density of staining. The first group included nuclei showing clustered, intensely labeled cells; these areas were restricted in extent and related to the maintenance of circadian rythms (intergeniculate leaf, suprachiasmatic nucleus, dorsal parts of either paraventricular thalamic nuclei or central gray), sleep-arousal cycle (supramamillary nucleus), or changes in arterial pressure (laterodorsal tegmental nucleus). The second group included nuclei showing scattered, moderately labeled cells; these areas were widespread at all rostrocaudal levels and related to either autonomic/neuroendocrine regulations (central gray, lateral habenula, hypothalamus) or motor behavior, orienting reflex and oculomotor coordination (unspecific subdivisions of both colliculi and their adjoining mesencephalic regions, zona incerta dorsal). The third group included nuclei with evenly distributed, faintly labeled cells; these areas, which, with few exceptions, covered almost the entire diencephalon, mainly concerned nuclei of multisensory convergence having functions in either discriminative tasks (laterodorsal and lateroposterior thalamic nuclei) or emotional responses (intralaminar and midline thalamic nuclei). The fourth group included nuclei free of labeling; these were areas that received the bulk of unimodal sensory/motor inputs (central inferior colliculus, pretectal optic nuclei, ventral medial geniculate nucleus, ventral anterior pretectal nucleus, dorsal lateral geniculate nucleus, ventrobasal complex; zona incerta ventral, parafascicular thalamic nucleus) and are thus the most discriminative regarding specific modalities. Variations in staining were of the same magnitude in both saline- and CP-injected animals. A sequential study spanning every postinjection hour revealed maximum staining at 1 h postinjection, which was followed by a progressive, time-related decrease. Increases in the number of labeled cells 1 h postinjection were significant in only a restricted number of nuclei showing low basal expression (Edinger-Westphal nucleus and paraventricular, supraoptic, and lateral hypothalamic nuclei); time-related reductions in staining that were correlated to sleep or quiescence behaviors finally resulted in staining equal to or below that seen in control animals. No structures showed significantly increased staining in relation to the full development of cystitis, i.e., with the increase of visceronociceptive inputs. Comparing the present results with those previously obtained at more caudal levels, it appears that subtelencephalic levels primarily driven by visceronociceptive inputs, i.e., those that increase and/or maintain their activity in parallel with the degree of nociception, are confined to brainstem-spinal cord junction levels and only comprise certain subdivisions of the nucleus of the solitary tract (nucleus medialis, nucleus commissuralis, and ventralmost part of area po  相似文献   

19.
20.
The feasibility of substituting glucose with fructose as a carbon source in Escherichia coli fermentations was investigated. Glucose, the most commonly used sugar in bacterial cultivations, is well-known to pose a number of drawbacks; the most important of which is the Crabtree effect, which results in acidogenesis. Fructose, a glucose structural isomer, offers a reasonable alternative for glucose, since its uptake and utilization are more tightly regulated. Comparative fermentation studies indicate that lower acetate excretion and higher biomass yields were attained in fructose-supplemented growth media compared with those of glucose media. More specifically, cells grown in defined media supplemented with fructose do not excrete detectable amounts of acetate, while about 40 mM of acetate was detected extracellularly in similar glucose cultures. A reduction in the initial growth rate of about 20% was observed with fructose, but final cell densities were about 70% higher compared with glucose supplements. Growth in complex LB media supplemented with fructose again resulted in higher biomass yields (up to 40%) and lower acetate excretion (30-40%) than the comparable glucose media. In bioreactor studies using LB media, acetate levels were reduced from 90 to less than 6 mM, while achieving a 25% improvement in biomass yield. When using richer media, cell densities of more than 40 g L-1 dry cell weight were attained in batch cultivation using fructose compared with 30 g L-1 for glucose. These results have immense applicability in the area of recombinant protein processes. Recombinant E. coli, overexpressing beta-galactosidase under the control of the strong pH-inducible promoter, achieved a volumetric recombinant protein yield of 2.2 million U mL-1 (corresponding to approximately 1.5 g L-1) in batch fructose cultures. This represents a 65% recombinant protein yield enhancement when compared to similar glucose cultivations.  相似文献   

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