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11.
The objective of this study was to determine the effects of fat supplementation from canola seed (CS) on ruminal fermentation and postruminal digestion of OM, carbohydrates, and energy of diets containing different levels of forage. Six ruminally and duodenally cannulated beef steers (354 kg +/- 18) were given ad libitum access to six isonitrogenous diets that were offered twice daily in a 6 x 6 Latin square design. Treatments were arranged as a 2 x 3 factorial with two forage levels (70 vs 30% of dietary DM as corn silage) and three forms of CS supplementation including no CS or CS added at 10% of dietary DM as whole CS treated with alkaline hydrogen peroxide or untreated crushed CS. Fat from CS provided 5% of dietary DM. The remaining dietary ingredients were corn, canola meal, molasses, and urea. No interactions (P > .05) between dietary forage level and CS supplementation were observed for ruminal characteristics or digestion of OM, carbohydrates, and energy in the rumen, postruminally, or in the total tract. Fat supplementation from CS did not affect (P > .05) DMI. With few exceptions, fat supplementation did not affect (P > .05) ruminal, postruminal, or total tract digestibilities of OM, structural and nonstructural carbohydrates, and GE. Ruminal disappearance of GE was decreased (P < .05) when diets were supplemented with fat from whole treated CS, and total tract digestibilities of OM and GE were decreased (P < .05) when diets were supplemented with fat from CS in either form. Ruminal pH, concentrations of NH3 N and total VFA, and molar proportions of acetate, propionate, and butyrate were not affected (P > .05) by fat supplementation. Results suggest that fat supplementation from CS (at 5% of dietary DM) as whole treated or untreated crushed had no negative effects on ruminal fermentation of OM, carbohydrates, or energy when steers were given ad libitum access to diets containing high or low forage.  相似文献   
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Treatments of Chinese hamster V79 cells during one cell cycle with a new type of topoisomerase II inhibitor, ICRF-193, which does not accumulate cleavable topoisomerase-DNA complexes induced both chromosome- and chromatid-type aberrations with high frequencies. Furthermore, ICRF-193 synergistically enhanced the yield of UVB-induced chromatid-type aberrations, chromatid exchanges in particular. Treated with ICRF-193 for the last 3 h before harvest, cells showed frequent incidence of chromatid-type aberrations and synergistic enhancement of UVB-induced chromatid-type aberrations, chromatid exchanges in particular. These results suggest that spontaneous and UVB-induced lesions might be ultimately transformed into chromatid-type aberrations by topoisomerase II-dependent checkpoint process(es) in the G2 phase of the cell cycle.  相似文献   
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28 isolates of canine parvovirus type-2 (CPV-2) were obtained from dogs with hemorrhagic gastroenteritis in Italy. The antigenic structure of CPV-2 isolates was characterized, using four discriminating monoclonal antibodies. In addition, four vaccinal strains were examined. Similar to reports from Australia and the United Kingdom, a much higher prevalence of CPV-2a (25/28 isolates) was observed than the other variant type, CPV-2b (3/28 isolates). DNA fragments (2.2 kbp) of representative strains of CPV-2, CPV-2a and CPV-2b were amplified by the polymerase chain reaction (PCR) and the products were digested by the restriction enzymes (RE) RsaI, HpaII, HindIII and PvuII. The RvaI enzyme allows the differentiation of CPV-2 from CPV-2a and CPV-2b.  相似文献   
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Spinal cord injury can lead to an exaggeration of transmission through spinal pathways, resulting in muscle spasticity, chronic pain, and abnormal control of blood pressure and bladder function. These conditions are mediated, in part, by N-methyl-D-aspartate (NMDA) receptors on spinal neurons, but the effects of cord injury on the expression or function of these receptors is unknown. Therefore, antibodies to the NMDA-R1 receptor subunit and binding of [3H]MK-801 were used to assess NMDA receptors in the spinal cord. Receptor density in rats with intact spinal cords was compared to that in rats 1 and 2 weeks after spinal cord transection (SCT) at the mid-thoracic level. At 1 and 2 weeks after SCT, [3H]MK-801 binding was reduced in most laminae in cord segments caudal to the injury, whereas no decrease in amount of R1 subunit immunoreactivity was observed. No significant changes in [3H]MK-801 binding and NMDA-R1 immunoreactivity could be seen rostral to the transection. Since [3H]MK-801 binding requires an open ion channel, the discrepancy between [3H]MK-801 binding and immunocytochemistry may indicate a loss of functional receptors without a consistent change in their total number. Therefore, the exaggerated reflexes that are well established in rats 2 weeks after cord injury must be mediated by a mechanism that withstands attenuation of NMDA receptor function.  相似文献   
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PURPOSE: To determine the frequency of remission in patients with essential blepharospasm and Meige syndrome. METHOD: Retrospective analysis of patients by means of questionnaire in an institutional setting. RESULTS: Among 238 patients diagnosed in a single institution as having essential blepharospasm or Meige syndrome, 27 (11.3%) claimed to be symptom free without curative surgery. The average time between onset and resolution in the patients who claimed remission was 4.85 years (range, 3 months to 22 years). Among these patients, the duration of remission averaged 6.33 years (range, 1 year to 14 years). CONCLUSION: Patients with essential blepharospasm or Meige syndrome have a small but definite potential for spontaneous remission of symptoms, particularly within the first 5 years after onset of symptoms.  相似文献   
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Flucloxacillin is a synthetic penicillin used in the treatment of Staphylococcal infections. Adverse reactions to the drug are believed to arise through covalent modification of proteins, with tissue damage occurring secondary to an immune reaction. Serum proteins have been shown by adduct-specific antibodies to be modified by flucloxacillin, but the nature and sites of modification have not been characterised. Here, in vitro studies on HSA have shown by MS that the modification of protein lysine residues occurs in a dose-, time- and site-dependent manner. Affinity, cation exchange and reversed phase chromatography prior to MS revealed in vivo modification of HSA with flucloxacillin in tolerant patients, with up to nine modified lysine residues being detected in each patient, and with modification of Lys190 and Lys212 being detected in 8/8 patients. It was also revealed for the first time that plasma proteins could be modified with the 5-hydroxymethyl metabolite of flucloxacillin, and that essentially the same Lys residues were targeted by both the parent drug and its metabolite. This study provides a detailed characterisation of sites of chemical modification of an endogenous target and reveals candidate peptides for T-cell and antibody assays of flucloxacillin hypersensitivity.  相似文献   
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A very general procedure entitled complete relaxation and conformational exchange matrix (CORCEMA) analysis has been developed to analyze the 2D-NOESY spectra of interacting systems undergoing multistate conformational exchange. This is an extension of earlier work from this laboratory on the methodological treatment of multistate conformational exchange [Krishna et al., Biopolymers 19, 2003 (1980)] and the theory of transferred NOESY for finite exchange off-rates [Lee and Krishna, J. Magn. Reson. 98, 36 (1992)]. The current theory is based on generalized rate matrices for relaxation and conformational exchange. The CORCEMA algorithm explicitly incorporates intermolecular dipolar cross relaxation between the molecules when they are complexed. It permits an analysis of NOESY intensities for the intra- as well as intermolecular contacts between the interacting molecules under a variety of binding conditions. Its application is illustrated on two examples of transferred NOESY simulations: (1) a two-state system involving a ligand and an enzyme forming a ligand-enzyme complex, and (2) a three-state system in which the ligand-enzyme complex can undergo a conformational transition from an "open state" to a "closed state," and can include conformational changes in both the complexed ligand and the complexed enzyme, such as hinge-bending motions. Simplifying expressions for generalized matrix analyses are derived for three limiting cases of the three-state system. This three-state example is illustrated using a hypothetical model of the hinge-bending motion in a thermolysin-inhibitor complex. It is shown that: (1) The neglect of cross relaxation between the interacting species in their complexed forms can lead to misleading conclusions on the "bound" conformation of the ligand. (2) If protein-mediated spin diffusion is dominant, caution is needed in analyses based on initial slopes alone due to one's inability to identify the exact range of the initial growth curve under poor signal/noise situations. (3) The neglect of conformational changes upon complexation, e.g., hinge-bending motions of the ligand-enzyme complex, can lead to erroneous results on the nature of "bound" conformations of the ligand. In this case, attempts to analyze the transferred NOESY data with a two-state model will result in a "virtual" conformation for the bound ligand. (4) When the hinge-bending rate is slower than the cross relaxation and enzyme off-rates, the bound conformation of a ligand deduced from the transferred NOESY experiment is more likely to represent nonspecific or weak binding in an open state of the enzyme.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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