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991.
992.
Birds on a commercial turkey Farm were treated with fenbendazole on two separate occasions. For each treatment, fenbendazole was administered in the feed for 3 days at 30 mg/kg. Mean Ascaridia dissimilis total counts in randomly selected birds were 14.4 and 33.0 prior to the first and second treatments, respectively, whilst post-treatment counts averaged only 0.1 and 0.3, respectively. Anthelmintic effectiveness as demonstrated by both treatments was >99.0%. No untoward effects were noted with either fenbendazole treatment. After fenbendazole withdrawal, routine treatments with piperazine dihydrochloride were commenced with no apparent anthelmintic effectiveness. Mean total nematode burdens rose to 153.9 with a high individual count of 451. The potential for severe ascaridiasis when effective anthelmintic intervention is precluded was demonstrated. 相似文献
993.
A E Theodorou K M Lawrence D Healy A M Whitehouse W White H Wilton-Cox S M Kerry R W Horton E S Paykel 《Journal of affective disorders》1991,23(3):99-106
Saturation binding of the alpha 2-adrenoceptor antagonist, 3H-yohimbine, and displacement of 3H-yohimbine with the alpha 2-adrenoceptor agonist, UK-14,304, were performed concurrently in platelet membranes obtained from drug-free depressed patients and healthy volunteers. Where possible platelet binding was repeated in depressed patients following treatment. The number and affinity of 3H-yohimbine binding sites did not differ between controls and depressed patients, or when depressed patients were divided on the basis of endogenicity (Newcastle or RDC criteria) or dexamethasone test result. The proportion of alpha 2-adrenoceptor binding sites with high affinity for UK-14,304 and KD values for the two states of the receptor did not differ in the total sample of depressed patients compared to controls. The KD for both states of the receptor and the proportion of sites with high affinity for UK-14,304 was lower in RDC non-endogenous patients than RDC endogenous patients. Treatment did not alter the total number of alpha 2-adrenoceptors or the proportion of sites with high affinity for UK-14,304, but reduced the KD for 3H-yohimbine and the KD of UK-14,304 for the low affinity state of the alpha 2-adrenoceptor. 相似文献
994.
Recent studies from this laboratory have found, contrary to a long-held belief, that synthetic peptides of a protein, as small as six residues, when immunized in their free form (i.e., without coupling to any carrier), elicit the formation of antibodies with submolecular binding specificities to preselected protein regions. These peptides could represent either the antigenic sites of the protein or surface regions that are not immunogenic when the intact protein is the antigen. In either case, the antibodies bind specifically to the intact protein, exclusively at the region used in immunization. Monoclonal antibodies with preselected specificities can also be produced by hybridoma technology from the spleens of the immunized animals. Furthermore, free synthetic peptides have been employed to generate T-cell lines and T-cell clones with specificities to preselected immunogenic locations and also to induce tolerance to such preselected locations. These fascinating breakthroughs indicate that free synthetic peptides may be used in the future as powerful tools in basic investigations and in therapeutic and diagnostic applications. 相似文献
995.
996.
A. K. Chepurov Z. M. Belomestnaya I. A. Donetskii G. V. Tsidvintseva 《Bulletin of experimental biology and medicine》1980,89(3):289-292
The thromboresistant properties of hydrophilic gels based on copolymers of nitrogen-containing heterocyclic vinyl compounds with vinyl monomers were investigated. The hydrophilic gels were shown to prevent adsorption of fibrinogen, activation of procoagulants, and adhesion of platelets. Hydrogen surfaces possess selective affinity for plasma albumin. The authors consider that the thromboresistant effect of hydrophilic gels is due to the competitive action of plasma albumin. Modification of hydrophilic gels increases their thromboresistant properties.Laboratory of Thromboresistant Materials, Institute of Transplantation of Organs and Tissues, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 296–298, March, 1980. 相似文献
997.
Genetic control of the immune response to haemoglobin. II. Studies using purified alpha-chain and beta-chain as immunogens 总被引:1,自引:0,他引:1
Mice of independent haplotypes and several recombinant inbred strains were immunized with highly purified preparations of either the alpha-chain or beta-chain subunit of human adult haemoglobin. Cells from the sensitized lymph nodes were challenged in vitro with the appropriate subunit (or in some cases both chains) and cell proliferation assessed by 3H-thymidine incorporation. Mice of the H-2b and H-2d haplotypes were high responders to alpha-chain while mice of the H-2f, H-2j, H-2k, H-2r, H-2s, H-2u, and H-2v haplotype were low responders. the low responsivenesss of B10.A(4R) and B 10.MBR and high responsiveness of B10 indicated that the Ir gene(s) determining responsiveness to the alpha-chain subunit resides in the I-A subregion of the mouse major histocompatibility complex. Mice of the H-2d, H-2f, and H-2s haplotypes were high responders and H-2b, H-2j, H-2a, and H-2u haplotype mice were low responders to beta-chain. H-2k, H-2p, H-2r, and H-2v haplotype mice were intermediate responders to beta-chain. The low responsiveness of B10.S(8R) and B10.TL and the high responsivenes of B10.S(9R) mapped the Ir gene(s) to beta-chain to the I-A subregion. Data collected from challenging high responder cells with both subunit indicated that alpha-chain and beta-chain do not crossreact. These results are discussed in reference to earlier observations suggesting that the low responsiveness of some strains of mice to priming and challenging using the intact haemoglobin molecule might be due to a negative regulatory influence mediated by one of the subunits. In the absence of this influence these mice would respond normally. 相似文献
998.
A new technique for the detection of glycoprotein antigens in immune complexes (IC) isolated from serum is described. The technique was developed with a model IC system consisting of ovalbumin (OVA)-rabbit anti-ovalbumin antibodies (aOVA), at 3 times antigen excess. OVA-aOVA IC added to normal human serum (NHS) were purified by absorption onto and elution from tubes coated with rheumatoid factor (RF) and were subjected to electrophoresis in polycrylamide gels. Concanavalin A (Con A) binding proteins were detected by treating the gels with radioiodinated Con A 125Con A), followed by autoradiography. IC isolated from sera of patients with Burkitt's lymphoma (BL) and Nasopharyngeal Carcinoma (NPC) were analyzed before and after reduction with dithioreitol. Two closely spaced proteins of about 40 kdalton were identified in the reduced samples in 26 of 30 BL sera (86%) and in 24 of 30 NPC sera (80%) but were not seen in 30 sera of African patients with a variety of unrelated tumors nor in 12 sera of European blood bank donors. 相似文献
999.
Martineau M Jalali GR Barber KE Broadfield ZJ Cheung KL Lilleyman J Moorman AV Richards S Robinson HM Ross F Harrison CJ 《Genes, chromosomes & cancer》2005,43(1):54-71
This study was undertaken in order to compare the interphase and metaphase cytogenetics of 28 patients with ETV6/RUNX1 positive acute lymphoblastic leukemia, at diagnosis and relapse. The median time to relapse was 26 months. The significant fusion positive population heterogeneity revealed at interphase by a commercial probe for ETV6/RUNX1 fusion has not been described before. Six diagnostic samples had a single abnormal population; others had up to five each, which differed in the numbers of RUNX1 signals, and in the retention or loss of the second ETV6 signal. In contrast, the number of fusion signals was more constant. At relapse, there were fewer populations; the largest or unique clone was sometimes a re-emergence of a minor, diagnostic one, with a retained copy of ETV6 and the most RUNX1 signals. Abnormal, fusion negative clones were identified in bone marrow samples at extra-medullary relapse. Variant three or four-way translocations, which involved chromosomes 12 and 21, were prominent among the complex rearrangements revealed by metaphase FISH. The frequency of their occurrence at diagnosis and reappearance at relapse, sometimes accompanied by minor clonal evolution, was another new observation. Other recurrent cytogenetic features included a second copy of the fusion signal in six cases, partial duplication of the long arm of the X chromosome in two cases, and trisomy 10 in three cases. In comparing our data with previously reported cases, a picture is beginning to emerge of certain diagnostic features, which may provide circumstantial evidence of an increased risk of relapse. 相似文献
1000.
Lodenyo H Rana F Mutuma GZ Kabanga JM Kuria JK Okoth FA 《African journal of health sciences》2005,12(1-2):49-54
Upper gastrointestinal complaints are common in Kenya. Though these have remained unchanged over the last 20 years, the pattern of upper gastrointestinal disease on endoscopic examination seems to be changing. There appears to be progressive increase in oesophagitis and cancer of the stomach. Peptic ulcer disease has remained stable while Cancer of the oesophagus is still common. The paper intends to report on endoscopic findings at the Centre for Clinical Research, Kenya Medical Research Institute (KEMRI) over the period October 1998 and May 2001. The sources of information are records made at the time of endoscopy and histology reports on biopsies taken. Seven hundred and sixty eight patients were endoscoped. The male to female ratio was 1.7:1 with mean age +/-SD of 40.8 +/-20.1 years and age range was 3 to 96 years. Majority of the patients had abnormal findings with gastritis being the most common ( 25.8%). It is concluded that gastritis is an important cause of morbidity in Kenya. Oesophagitis, mainly due to gastroesophageal reflux disease, seems to be on the increase. Gastric cancer is not as rare as previously thought and peptic ulcer disease is still common. 相似文献