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21.
A second examination at the expense of the party adjudged to be in error is based on Section 13 of the Meat Inspection Act in the Netherlands, which has been elaborated in Sections 51 and 51a of the Meat Inspection Order. The procedure to be adopted by the second veterinary-surgeon inspector, however, has not been stipulated. The need for clear instructions is stressed. The present paper was designed to promote objectivity and uniformity in second inspections to provide legal security for the owner of the slaughtered animal as well as for the first veterinary-surgeon inspector. 相似文献
22.
The parathyroid glands of rats given 150 ppm fluoride in the drinking water for 10 weeks are evaluated ultrastructurally and compared to the parathyroid glands of untreated rats. As a result of fluoride ingestion, the majority of the parathyroid cells are dark chief cells, indicating that these cells are in the active stages of the secretory cycle. More significantly, in the fluoride-treated rats, the cytoplasmic organelles of the dark chief cells are even more developed that those seen in the dark chief cells of untreated rats. The dark cells contain an electron-dense cytoplasm with abundant lamellar arrays of rough endoplasmic reticulum, spiral aggregations of free ribosomes, multiple dilated Golgi complexes, and increased numbers of secretory granules. The cells are at a minimum dimension with maximum tortuosity of the plasma membranes; and, as a result, large intercellular spaces are often seen between contiguous cells. Based on these observations, it is suggested that, in the fluoride-treated rat, a type of secondary hyperparathyroidism develops resulting in an increase in the organelles involved in protein synthesis and secretion. 相似文献
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KA Keay LJ Crowfoot NS Floyd LA Henderson MJ Christie R Bandler 《Canadian Metallurgical Quarterly》1997,762(1-2):61-71
Differentiating the binding properties of applied lectins should facilitate the selection of lectins for characterization of glycoreceptors on the cell surface. Based on the binding specificities studied by inhibition assays of lectin-glycan interactions, over twenty Gal and/or GalNAc specific lectins have been divided into eight groups according to their specificity for structural units (lectin determinants), which are the disaccharide as all or part of the determinants and of GalNAc alpha 1-->Ser (Thr) of the peptide chain. A scheme of codes for lectin determinants is illustrated as follows: (1) F (GalNAc alpha 1-->3GalNAc), Forssman specific disaccharide--Dolichos biflorus (DBL), Helix pomatia (HPL) and Wistaria floribunda (WFL) lectins. (2) A (GalNAc alpha 1-->3 Gal), blood group A specific disaccharide--Codium fragile subspecies tomentosoides (CFT), Soy bean (SBL), Vicia villosa-A4 (VVL-A4), and Wistaria floribunda (WFL) lectins. (3) Tn (GalNAc alpha 1-->Ser (Thr) of the protein core)--Vicia villosa B4 (VVL-B4), Salvia sclarea (SSL), Maclura pomifera (MPL), Bauhinia purpurea alba (BPL) and Artocarpus integrifolia (Jacalin, AIL). (4) T (Gal beta 1-->3GalNAc), the mucin type sugar sequences on the human erythrocyte membrane(T alpha), T antigen or the disaccharides at the terminal nonreducing end of gangliosides (T beta)--Peanut (PNA), Bauhinia purpurea alba (BPL), Maclura pomifera (MPL), Sophora japonica (SJL), Artocarpus lakoocha (Artocarpin) lectins and Abrus precatorius agglutinin (APA).(5) I and II (Gal beta 1-->3(4)GlcNAc)--the disaccharide residue at the nonreducing end of the carbohydrate chains derived from either N- or O-glycosidic linkage--Ricinus communis agglutinin (RCA1), Datura stramonium (TAL, Thorn apple), Erythrina cristagalli (ECL, Coral tree), and Geodia cydonium (GCL). (6) B (Gal alpha 1-->3Gal), human blood group B specific disaccharide--Griffonia(Banderiaea) simplicifolia B4 (GSI-B4). (7) E (Gal alpha 1-->4Gal), receptors for pathogenic E. coli agglutinin, Shiga toxin and Mistletoe toxic lectin-I (ML-I) and abrin-a. 相似文献
25.
LJ Loescher 《Canadian Metallurgical Quarterly》1999,22(1):96-102
This study evaluated effective resistances on the ventricular surfaces of arterially-perfused rabbit hearts. Effective resistances were determined with a four-electrode array that was parallel or perpendicular to epicardial fibers. Resistance along or across epicardial fibers was determined by applying current to the epicardium with two parallel line electrodes and measuring potentials in the region between the electrodes. Computer simulations were performed to gain insight into the distribution of current in the ventricular wall. The effective resistances were not different along versus across fibers. Simulations showed that transmural rotation of fibers causes current to be distributed differently when the electrode is oriented perpendicular versus parallel to epicardial fibers. When the array is oriented so that epicardial current is across fibers, the fraction of current that flows transmurally and along the deeper fibers increases while the fraction of current that flows epicardially decreases. This introduces isotropy of the effective resistance. Thus, in contrast to isolated cardiac fibers, the ventricular epicardium exhibits isotropic effective resistance due to transmural rotation of fibers. The rotation and isotropic resistance may be important for cardiac electrical behavior and effects of electrical current in the ventricles. 相似文献
26.
G. Melnyk A. Leithe-Jasper P. Rogl R. Skolozdra 《Journal of Phase Equilibria and Diffusion》1999,20(2):113-118
Phase equilibria were established in the Nb-Fe-Sb ternary system for an isothermal section at 600 °C. Investigation of the
phase relations was based on light optical microscopy, electron probe microanalysis, and X-ray diffraction experiments on
arc-melted bulk alloys, which were annealed up to 1400 h. One ternary compound was observed: NbFeSb (MgAgAs type) without
a significant homogeneity region at 600 °C. Except for NbFe2−y
, mutual solid solubilities at 600 °C were found to be very low, for example, <1 at.% Fe and <1 at.% Nb in the binary Nb antimonides
and Fe antimonides, respectively. The binary Laves phase NbFe2−y
with the MgZn2 type exhibits an extended homogeneity region dissolving at 600 °C up to 7 at.% Sb in the ternary without change of its structure
type. 相似文献
27.
G Galazka LJ Windsor H Birkedal-Hansen JA Engler 《Canadian Metallurgical Quarterly》1999,38(4):1316-1322
Human stromelysin-1 (SL-1) is a member of the stromelysin subfamily of matrix metalloproteinases (MMPs). The MMPs play a major role in the degradation of the extracellular matrix (ECM) during normal and pathological conditions. SL-1 like the other MMPs can be activated in vitro by the stepwise removal of the propeptide that contains a single unpaired cysteine which coordinates the active site zinc. Other residues in the propeptide also play a role in maintaining the latency of the enzymes. Deletion mutants and single-site amino acid replacements within the propeptide of a carboxyl-terminally truncated stromelysin-1 (mini-SL-1) were constructed and expressed in Escherichia coli to further examine what amino acids within the propeptide of SL-1 are important for maintaining latency. While the natural enzyme displayed some limited tendency to spontaneously (autolytically) convert to lower Mr in a stepwise manner and finally to the fully processed form, all of the truncation mutants of more than 19 amino acids generated in E. coli showed greatly accelerated self-cleavage indicative of diminished stability and/or resistance to proteolysis of the residual propeptide. Mutant Delta63 as well as other mutants in which most of the propeptide had been deleted no longer responded to exposure to the organomercurial APMA by accelerated autolytic processing. Rather, APMA inhibited the autolytic processing in these mutants, further confirming the complexity of the action of this organomercurial in the activation of pro-MMPs. 相似文献
28.
HC Kwaan M Levin S Sakurai O Kucuk MW Rooney LJ Lis JW Kauffman 《Canadian Metallurgical Quarterly》1997,26(6):1061-1068
Digital gangrene was observed in a patient who had angiographic findings of digital arterial occlusion. The patient's blood showed a marked red blood cell aggregation with rouleaux formation in long chains, which could not be dispersed at shear rates up to 200 sec-1. Studies of the patient's blood revealed the presence of an abnormal fibrinogen capable of aggregating normal red blood cells. This fibrinogen was found by Raman spectroscopy to have an increased alpha-helical content, whereas the beta-sheet content was decreased. Defibrinogenation therapy with ancrod resulted in a dramatic symptomatic relief. The disappearance of the abnormal fibrinogen 6 months later and an absence of a family history indicate that this dysfibrinogenemia was acquired. 相似文献
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