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121.
A trial was conducted to compare the efficacy of intranasal vaccination in protecting goats against pneumonic pasteurellosis with intramuscular vaccination using an oil adjuvant vaccine, and a combination of the two methods. Forty goats were divided into four equal groups. Group 1 was vaccinated twice intranasally with formalin-killed Pasteurella haemolytica A2, group 2 was vaccinated twice intramuscularly with an oil adjuvant vaccine containing P haemolytica A7, and group 3 was initially vaccinated intranasally with the formalin-killed P haemolytica A2 followed by intramuscular vaccination with the oil adjuvant vaccine. In each group the two vaccinations were carried out four weeks apart. Group 4 was the unvaccinated control group. All goats were challenged intratracheally with 4 ml of an inoculum containing live P haemolytica A2 at a concentration of 1.3 x 10(7) colony forming units/ml two weeks after the last vaccination and were killed 14 days after the challenge. Although group 2 showed the highest clinical score following the challenge, deaths were observed only in group 3. Three goats in group 1 had pneumonic lung lesions, compared with six goats in group 2 and all the goats in groups 3 and 4. The lung lesions in group 1 were significantly (P < 0.05) less severe than in groups 3 and 4. Similarly, the lesions in group 2 were markedly less severe than in groups 3 and 4, although the differences were not significant. The difference between the extent of the lung lesions in the goats in groups 1 and 2 was not significant. Antibody against P haemolytica A2 in group 1 reached peak levels and was significantly (P < 0.01) higher than in the control group one week after the second vaccination, before declining. 相似文献
122.
AW Hsing JK McLaughlin WH Chow LM Schuman HT Co Chien G Gridley E Bjelke S Wacholder WJ Blot 《Canadian Metallurgical Quarterly》1998,77(4):549-553
The mRNA expression of presenilin-1 (PS1) and beta-amyloid precursor protein (betaAPP) was investigated in the embryonic day 20 rat olfactory bulb, nasal cavity, and inner ear using in situ hybridization histochemistry. In the olfactory bulb, PS1 mRNA was strongly expressed in both olfactory bulb neuroepithelium and the differentiating olfactory bulb. In contrast, betaAPP mRNA was preferentially expressed in differentiating fields. In the nasal cavity, PS1 mRNA was strongly expressed throughout the olfactory epithelium, while betaAPP mRNA expression was concentrated in the middle part of the epithelium. In the membrane labyrinth of the inner ear, although PS1 mRNA was evenly distributed in both sensory epithelium and supporting cells, betaAPP mRNA was exclusively expressed in the sensory epithelium. These data suggest that PS1 is expressed earlier than betaAPP, and that PS1 and betaAPP co-operatively play pivotal roles in the development of the olfactory and vestibulocochlear systems. 相似文献
123.
Mitotic centromere-associated kinesin (MCAK) is recruited to the centromere at prophase and remains centromere associated until after telophase. MCAK is a homodimer that is encoded by a single gene and has no associated subunits. A motorless version of MCAK that binds centromeres but not microtubules disrupts chromosome segregation during anaphase. Antisense-induced depletion of MCAK results in the same defect. MCAK overexpression induces centromere-independent bundling and eventual loss of spindle microtubule polymer suggesting that centromere-associated bundling and/or depolymerization activity is required for anaphase. Live cell imaging indicates that MCAK may be required to coordinate the onset of sister centromere separation. 相似文献
124.
Egg shell colour is affected by laying cage design 总被引:1,自引:0,他引:1
1. When laying hens are stressed some retain their eggs in the shell gland beyond the normal time of laying and this can result in the deposition of extra-cuticular calcium which makes brown eggs appear paler. 2. Three different types of enriched modified cage were compared: the location where eggs were laid was recorded and shell colour was measured using a reflectometer. 3. In 2 types of cage with enclosed nest boxes more eggs (80%) were laid in the nests than in a design with nest hollows in the open part of the cage (41%). 4. The eggs from the cages with enclosed nests were darker (had less extraneous calcium) than those with open nest hollows. This implies that in the designs with nest boxes fewer eggs had been retained and the hens may have been less stressed. 5. The results support previous evidence that to reduce stress and improve welfare it is desirable to provide enclosed nest sites for caged laying hens. 相似文献
125.
U Beyer T Roth P Schumacher G Maier A Unold AW Frahm HH Fiebig C Unger F Kratz 《Canadian Metallurgical Quarterly》1998,41(15):2701-2708
One strategy for improving the selectivity and toxicity profile of antitumor agents is to design drug carrier systems employing soluble macromolecules or carrier proteins. Thus, five maleimide derivatives of chlorambucil were bound to thiolated human serum transferrin which differ in the stability of the chemical link between drug and spacer. The maleimide ester derivatives 1 and 2 were prepared by reacting 2-hydroxyethylmaleimide or 3-maleimidophenol with the carboxyl group of chlorambucil, and the carboxylic hydrazone derivatives 5-7 were obtained through reaction of 2-maleimidoacetaldehyde, 3-maleimidoacetophenone, or 3-maleimidobenzaldehyde with the carboxylic acid hydrazide derivative of chlorambucil. The alkylating activity of transferrin-bound chlorambucil was determined with the aid of 4-(4-nitrobenzyl)pyridine (NBP) demonstrating that on average 3 equivalents were protein-bound. Evaluation of the cytotoxicity of free chlorambucil and the respective transferrin conjugates in the MCF7 mammary carcinoma and MOLT4 leukemia cell line employing a propidium iodide fluorescence assay demonstrated that the conjugates in which chlorambucil was bound to transferrin through non-acid-sensitive linkers, i.e., an ester or benzaldehyde carboxylic hydrazone bond, were not, on the whole, as active as chlorambucil. In contrast, the two conjugates in which chlorambucil was bound to transferrin through acid-sensitive carboxylic hydrazone bonds were as active as or more active than chlorambucil in both cell lines. Especially, the conjugate in which chlorambucil was bound to transferrin through an acetaldehyde carboxylic hydrazone bond exhibited IC50 values which were approximately 3-18-fold lower than those of chlorambucil. Preliminary toxicity studies in mice showed that this conjugate can be administered at higher doses in comparison to unbound chlorambucil. The structure-activity relationships of the transferrin conjugates are discussed with respect to their pH-dependent acid sensitivity, their serum stability, and their cytotoxicity. 相似文献
126.
We have determined if peripheral nerve stimulation altered the increased spontaneous release of immunoreactive (ir)-galanin that is found in the superficial dorsal horn of the spinal cord of neuropathic rats. Using the antibody microprobe technique to study the localized sites of ir-galanin release in vivo, we found that high intensity electrical stimulation of the injured nerve resulted in a further increase in ir-galanin release in the superficial dorsal horn, with no significant persistence of ir-galanin after release. Release of ir-galanin at stimulus strengths sufficient to activate C fibres, in an area of the spinal cord thought to be concerned with nociceptive transmission, indicates a possible role for this peptide in the spinal modulation of pain after peripheral nerve injury. 相似文献
127.
128.
We report a double dissociation between visuo-spatial abilities and semantic knowledge (knowledge of the names and attributes of objects and people), in two brain-injured people with longstanding stable impairments, using a wide range of tests to explore the extent of the dissociation, MU, who has bilateral lesions of occipito-parietal cortex, shows severe spatial disorientation with relatively well-preserved semantic knowledge. He is contrasted with JBR, who has bilateral temporal lobe damage and shows severe semantic problems and no impairment on visuo-spatial tasks. Our findings thus demonstrate a double dissociation between the performance of semantic and spatial tasks by MU and JBR. This pattern is consistent with Ungerleider and Mishkin's (1982) neurophysiological hypothesis of separable cortical visual pathways; one which is specialised for spatial perception and follows a dorsal route from occipital to parietal lobes, and the other following a more ventral route from occipital to temporal lobes, whose target is semantic information needed in specifying what an object is. 相似文献
129.
Conventional subtraction library techniques or DNA-transfection studies are standard techniques applied for identification and isolation of genes relevant in monogenetic diseases like Fanconi anemia (FA). The differential display technique (DDT) was developed to compare mRNA expression between a mutant cell line and its syngeneic control and allows comparison of almost all mRNA species within a short time. However, for identification of genes relevant in monogenetic diseases, no syngeneic cell model is available. In this report, we show that the use of nonsyngeneic diploid human fibroblasts does not increase the number of differentially displayed bands due to diversity of untranslated regions. cDNA bands with a length of up to 1000 bp were obtained and applied to DDT. After screening of about 13000 cDNA bands, only 0.5% were found to be differentially expressed between FA and control cells. Finally, three mRNAs were cloned and verified in Northern blot experiments to be differentially expressed in FA fibroblasts. The low number of differentially displayed cDNA bands in DDT indicates the usefulness of this statistical, molecular approach for identification of multiple genes dysregulated in gene regulation cascades potentially relevant for cell cycle disturbances. 相似文献
130.
EB Samrén CM van Duijn S Koch VK Hiilesmaa H Klepel AH Bardy GB Mannagetta AW Deichl E Gaily ML Granstr?m H Meinardi DE Grobbee A Hofman D Janz D Lindhout 《Canadian Metallurgical Quarterly》1997,38(9):981-990
PURPOSE: To quantify the risks of intrauterine antiepileptic drug (AED) exposure in monotherapy and polytherapy. METHODS: Data from five prospective European studies totaling 1,379 children were pooled and reanalyzed. Data were available for 1,221 children exposed to AED during pregnancy and for 158 children of unexposed control pregnancies. RESULTS: Overall, when comparing a subgroup of 192 children exposed to AED with 158 children of matched nonepileptic controls, there was an increased risk of major congenital malformations (MCA) in children exposed to AED during gestation [relative risk (RR) 2.3; 95% confidence interval (CI): 1.2-4.7]. A significant increase in risk was found for children exposed to valproate (VPA) (RR 4.9; 95% CI: 1.6-15.0) or carbamazepine (CBZ) (RR 4.9; 95% CI: 1.3-18.0) in monotherapy. When comparing different AED regimens during all 1,221 pregnancies, risks of MCA were significantly increased for the combination of phenobarbital (PB) and ethosuximide (RR 9.8; 95% CI: 1.4-67.3) and the combination of phenytoin, PB, CBZ, and VPA (RR 11.0; 95% CI: 2.1-57.6). Offspring of mothers using > 1,000 mg VPA/day were at a significantly increased risk of MCA, especially neural tube defects, compared to offspring exposed < or =600 mg VPA/day (RR 6.8; 95% CI: 1.4-32.7). No difference in risk of MCA was found between the offspring exposed to 601-1,000 mg/day and < or =600 mg/day. CONCLUSIONS: This reanalysis shows that VPA is consistently associated with an increased risk of MCA in babies born to mothers with epilepsy. Significant associations were also observed with CBZ. Larger prospective population-based studies are needed to evaluate the risks of many other less frequently prescribed treatment regimens, including newly marketed AEDs. 相似文献