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171.
The author describes how his interest in the nutritional value of soybeans led to a trail of research that had many ramifications. In an attempt to account for the poor nutritional value of raw soybeans and the beneficial effect of heat treatment, a protein displaying hemagglutinating activity and capable of inhibiting the growth of rats was isolated and characterized. This protein subsequently proved to be an example of a class of proteins that were later referred to as "lectins". Lectins were also isolated from kidney beans and shown to be even more toxic than the soybean lectin. Concurrent studies with the soybean trypsin inhibitors revealed that these proteins inhibited growth by stimulating the secretory activity of the pancreas and could in the long term cause acinar cell adenoma of the pancreas. Acute experiments with human subjects showed that the human pancreas also responded to the stimulatory effects of the so-called Bowman-Birk soybean inhibitor. The studies on soybean trypsin inhibitors were expanded to include a protease inhibitor present in blood, alpha-1-antitrypsin, a deficiency of which leads to emphysema in humans. The mechanism whereby this protein inhibits leucocyte elastase was investigated. On the basis of these results the intratracheal administration of a synthetic peptide inhibitor of elastase attached to albumin microspheres was found to prevent elastase-induced emphysema in hamsters.  相似文献   
172.
Studies evaluating the effects of dobutamine in horses do not consistently report increases in cardiac output despite increases in arterial blood pressure. The concurrent administration of the α2 agonist clonidine, in people, inhibited the chronotropic effects of dobutamine and increased left ventricular stroke work ( Zimpfer et al. 1982 ). Our study was performed to determine if pre‐medication with an α2 agonist affects the response to dobutamine in anaesthetized horses. Eleven horses were anaesthetized on four separate occasions for one of four randomly assigned treatments; (I) no xylazine, no dobutamine (II) xylazine, no dobutamine (III) no xylazine, dobutamine, and (IV) xylazine, dobutamine. Horses received 0.02 mg kg?1 of butorphanol IV 10 minutes prior to anesthetic induction. Two minutes prior to induction, groups II and IV received 0.5 mg kg?1 of IV xylazine. Anaesthesia was induced with 6–7 mg kg?1 of thiopental and maintained with halothane. End‐tidal halothane concentrations were maintained between 1.1 and 1.2% in groups I and III, and 0.9–1.0% for groups II and IV. Heart rate, cardiac output, right atrial pressure, and systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressure were recorded 30 minutes after beginning halothane anaesthesia (T10). Cardiac output was estimated using Lithium dilution ( Linton et al. 2000 ). Baseline measurements were repeated twice, at 5‐minute intervals (T5 and T0). At time 0 (T0), an IV infusion of either saline (100 mL hour?1) or dobutamine (0.001 mg kg?1 minute?1) was started and data recorded at 5‐minute intervals for 30 minutes (T5 – T30). Stroke volume and systemic vascular resistance (SVR) were calculated. Data were analysed using repeated measures anova (p < 0.01 significant) and Newman–Keuls for multiple comparisons. Cardiac output and stroke volume increased over time in groups III and IV. Cardiac index was higher in groups III and IV than in groups I and II from T10 until completion of the study. Estimates of cardiac index at T30 for groups I–IV were 45 ± 9, 46 ± 11, 71 ± 11, and 78 ± 19 mL kg?1 minute?1, respectively (mean ± SD). Stroke index was higher in groups III and IV than in groups I and II from T15 to T30. Values for stroke index at T30 for groups I–IV were 0.98 ± 0.19, 1.11 ± 0.18, 1.46 ± 0.21, 1.74 ± 0.33 mL kg?1. Heart rate decreased from T10–T30 in groups I and II. Heart rate was greater in groups I and III than in groups II and IV at T5 and T0. Values for heart rate at T0 for groups I–IV were 48 ± 5, 42 ± 5, 50 ± 4, 43 ± 4 beats minute?1. Systolic arterial pressure, DAP and MAP were higher in groups III and IV than in groups I and II from T5 to T30. There were no differences in SVR between groups. Dobutamine at 0.001 mg kg?1 minute?1 increased cardiac output, blood pressure, and stroke volume. Premedication with xylazine at 0.5 mg kg?1 did not appear to affect the response to dobutamine.  相似文献   
173.
Intact seed of 475 genebank accessions of Citrullus ( C. lanatus var. lanatus and C. lanatus var. citroides) were analyzed for percent oil content using TD-NMR. Extracts from whole seed of 96 accessions of C. lanatus (30 var. citroides, 33 var. lanatus, and 33 egusi), C. colocynthis (n = 3), C. ecirrhosus (n = 1), C. rehmii (n = 1), and Benincasa fistulosa (n = 3) were also analyzed for their fatty acids content. Among the materials analyzed, seed oil content varied from 14.8 to 43.5%. Mean seed oil content in egusi types of C. lanatus was significantly higher (mean = 35.6%) than that of either var. lanatus (mean = 23.2%) or var. citroides (mean = 22.6%). Egusi types of C. lanatus had a significantly lower hull/kernel ratio when compared to other C. lanatus var. lanatus or C. lanatus var. citroides. The principal fatty acid in all C. lanatus materials examined was linoleic acid (43.6-73%). High levels of linoleic acid were also present in the materials of C. colocynthis (71%), C. ecirrhosus (62.7%), C. rehmii (75.8%), and B. fistulosa (73.2%), which were included for comparative purposes. Most all samples contained traces (<0.5%) of arachidonic acid. The data presented provide novel information on the range in oil content and variability in the concentrations of individual fatty acids present in a diverse array of C. lanatus, and its related species, germplasm.  相似文献   
174.
Bovine Neonatal Pancytopenia (BNP), a bleeding syndrome of neonatal calves, is caused by alloantibodies absorbed from the colostrum of particular cows. A commercial BVD vaccine is the likely source of alloantigens eliciting BNP associated alloantibodies. We hypothesized that the rare occurrence of BNP in calves born to vaccinated dams could be associated with genetic differences within dams and calves. We found that the development of BNP within calves was a heritable trait for dams, not for calves and had a high heritability of 19%. To elucidate which genes play a role in the development of BNP we sequenced candidate genes and characterized BNP alloantibodies. Alloantigens present in the vaccine have to be presented to the dam’s immune system via MHC class II, however sequencing of DRB3 showed no differences in MHC class II haplotype between BNP and non-BNP dams. MHC class I, a highly polymorphic alloantigen, is an important target of BNP alloantibodies. Using a novel sequence based MHC class I typing method, we found no association of BNP with MHC class I haplotype distribution in dams or calves. Alloantibodies were detected in both vaccinated BNP and non-BNP dams and we found no differences in alloantibody characteristics between these groups, but alloantibody levels were significantly higher in BNP dams. We concluded that the development of BNP in calves is a heritable trait of the dam rather than the calf and genetic differences between BNP and non-BNP dams are likely due to genes controlling the quantitative alloantibody response following vaccination.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0129-0) contains supplementary material, which is available to authorized users.  相似文献   
175.
Abstract

CASE HISTORY: A 14-year-old Cleveland Bay cross gelding was presented with severe urinary incontinence that had been present for 1 year, and chronic polydipsia and polyuria over 4 years. Water intake had been recorded as 240 L over a 24-hour period.

CLINICAL FINDINGS: The horse had marked urinary incontinence and polyuria and polydipsia. The urine was markedly hyposthenuric, but no abnormalities on urinalysis were detected. There were no other abnormal clinical or neurological signs. Haematological and serum biochemical examinations showed no abnormalities and ultrasonographic and endoscopic examination of the urinary tract did not reveal any abnormalities. The horse underwent a modified water deprivation test and failed to concentrate its urine after 5 days. 1-desamino-8-d-arginine vasopressin (DDAVP) was administered I/V but the urine remained isosthenuric with a specific gravity of 1.010.

DIAGNOSIS: Nephrogenic diabetes insipidus. A definitive cause of the urinary incontinence was not found but overflow incontinence was considered a possibility.

CLINICAL RELEVENCE: Despite being a rare condition in the horse diabetes insipidus should be considered in cases of severe polydipsia and polyuria in mature horses.  相似文献   
176.
The purpose of the present study was to compare Rendement Napole (RN) classification from glycolytic potential (GP) and DNA techniques, and to study the effect of the RN gene on performance, carcass, muscle quality, and sensory traits. Progeny (N = 118) from the mating of 15 purebred Hampshire sires to York x Landrace females were classified for RN gene status using the GP of the loin and polymerase chain reaction-restriction fragment length polymorphism sequence methodology. Females mated in the study (N = 32) were considered normal (rn+/rn+) based on a loin GP measurement taken on samples collected by live press biopsy. Progeny were randomly selected for harvest within a litter for each sire. Observed mean, standard deviation, and range of progeny loin GP values were 132.2, 30.7, and 70.0 to 193.0 micromol/g, respectively. The GP data were not normally distributed. Peak numbers of observations occurred between 120 and 129 micromol/g and 160 to 169 micromol/g. Pigs with a loin GP of > 150 micromol/g were classified RN-/rn+ based on the observed valley between the peak values, resulting in 37 pigs classified as RN-/rn+ and 81 pigs classified as rn+/rn+. Using DNA procedures, 81 RN-/rn+ and 37 rn+/rn+ pigs were observed. All classification errors occurred when GP values were < or = 150 micromol/g, with 30 of 44 and 14 of 44 classification errors occurring when loin GP values were between 121 and 150 micromol/g and 70 and 120 micromol/g, respectively. Gene effects, based on DNA results, were evaluated using mixed-model procedures with fixed effects of DNA genotype and gender, and random sire and litter effects. No RN genotype differences for growth rate,10th-rib backfat, or loin muscle area were observed. Loins from the RN-/rn+ pigs had significantly (P < 0.05) lower ultimate pH (0.16 units), greater GP (50.3 micromol/g), greater drip loss (0.93%), paler objective color (L*, 1.66 units), paler visual color (0.31 units), and lower firmness (0.61 units) scores. Additionally, loins from RN-/rn+ pigs had significantly (P < 0.05) lower marbling scores (0.68 units) and intramuscular fat content (0.25%) and greater cooking loss (2.51%). Cooked moisture, juiciness score, and mechanical and sensory tenderness measures did not differ between genotypes. The GP-based classification did not correctly classify RN genotype in the present study, emphasizing the importance of the direct DNA analysis for estimation of gene frequency and effects. The DNA-based genotype results clearly indicate the RN- allele has negative effects on muscle quality measures.  相似文献   
177.
The objective of this research was to evaluate a biallelic genetic marker identified in the first promoter region of the bovine IGF-I gene. The point mutation was identified as a T-to-C transition by sequencing the polymorphic fragments. A PCR-RFLP procedure was developed for determining the marker genotypes. Marker genotypes were determined for 760 Angus calves from divergent lines that were created by selection for high or low serum IGF-I concentration (allele A: 63.9%, B: 36.1%). Data were analyzed using the multiple-trait derivative-free restricted maximum likelihood computer programs with animal models. The full animal model included fixed effects of marker genotype, birth year, season of birth, sex, age of dam, and selection line; random effects of animal, maternal genetic, and maternal permanent environmental effects; and a covariate for age of calf. Traits analyzed included blood serum IGF-I concentrations on d 28, 42, and 56 of the postweaning test, mean IGF-I concentration, birth weight, weaning weight, on-test weight, off-test weight, off-test hip height, postweaning gain, and weight gain during the 20-d period immediately after weaning. Results from the analysis across selection lines showed a significant association of the BB genotype with higher weight gain during the first 20 d after weaning and a slight dominance effect of the marker on postweaning gain. Analysis within the low IGF-I line also showed a significant association of the BB genotype with higher weight gain during the first 20 d after weaning and with on-test weight, although analysis within the high IGF-I line did not show any significant association. The associated effects of the marker need to be verified in other cattle populations.  相似文献   
178.
A rat, given a single oral dose of [14C] cymoxanil, 1-(2-cyano-2-methoxyimino-[2-14C]-acetyl)-3-ethylurea, eliminated 91% of the radioactivity within 72 h. The urine contained 71%, the faeces 11%, and the expired air about 7% of the radiolabel; no 14C residue was found in the internal organs. Greater than 70% of the radioactivity in the urine was identified. The major metabolite was characterised as glycine, both free and conjugated, as hippuric acid and phenylaceturic acid [N-(phenylacetyl)-glycine], and probably in the form of polypeptides of low molecular weight. The other metabolites identified included 2-cyano-2-methoxyiminoacetic acid, 2-cyano-2-hydroxyiminoacetic acid and 1-ethylimidazolidine-2, 4, 5-trione. The minor metabolites included succinic acid and 2-oxoglutaric acid which indicated reincorporation of metabolic 14C. Cymoxanil, as such, was not detected in the urine.  相似文献   
179.
180.
Radiation and isotopic techniques have been used in a number of ways to study Babesia and Theileria parasites (piroplasms), and in attempts to vaccinate animals against diseases induced by these agents. Work involving the piroplasm infections of cattle is reviewed in this paper.Some success has been achieved by using radiation to modify tick or bovine stages of parasites, for use as potential vaccines. Radiation has also been used to induce immunosuppression in laboratory animals, in an effort to render them susceptible to bovine piroplasms, particularly Theileria. Isotope tracer techniques have been used for labelling parasites, and for studying metabolic pathways. Encouraging results, particularly with regard to vaccine development, indicate the importance of radiation techniques in the study and control of piroplasms of cattle.  相似文献   
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