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1.
AA Guglielmone CI Lugaresi MM Volpogni OS Anziani VR Vanzini 《Canadian Metallurgical Quarterly》1997,70(1-3):33-39
The efficacy of vaccination of Argentinean cattle against babesiosis and anaplasmosis using live immunogens was tested to detect specific antibodies in samples obtained about 60 days after vaccination. Under these conditions a higher than expected proportion of cattle failed to show antibodies against Babesia bigemina. Therefore, a study was designed to evaluate if this failure was due to insensitivity of the routine test to detect antibodies to B. bigemina or to lack of infectivity of the live vaccine. Four groups (G) of cattle were each inoculated subcutaneously with 10 million Babesia bovis (vaccinal strain R1A), 10 million B. bigemina (vaccinal strain S1A) and 10 million Anaplasma centrale (strain M1). G1 and G2 consisted of ten Angus bulls 20-24 months old and ten Angus bulls 15-18 months old, respectively; G3 and G4 consisted of ten and 16 Holstein 1-month-old male calves, respectively. Blood samples were obtained on days 0, 10, 20, 30, 40, 50 and 60 after vaccination and the sera were analysed with an indirect immunofluorescent (IFA) test to detect antibodies to B. bovis (baseline dilution for a positive result 1:60) and B. bigemina (baseline dilution 1:120). Positive IFA titres were considered as evidence of the infectivity of the Babesia vaccinal strains contained in the vaccine. All Angus bulls were found positive to antibodies against both Babesia species, by day 20 (B. bovis) and day 30 (B. bigemina), whereas 10-25% of Holstein calves were negative throughout. The partial lack of vaccine infectivity in the calves was considered to be a consequence of innate resistance of young calves to Babesia. Antibody titres to B. bovis and B. bigemina declined by day 60 after vaccination. However, all cattle that were positive to B. bovis antibodies on day 50 were still positive to the IFA test 10 days later while 10%, 30% and 12% of cattle of G1, G2 and G3 that were positive to B. bigemina antibodies on day 50 after vaccination were found negative to the IFA test on day 60. In future, samples taken on days 40-50 will be used for detection of B. bigemina antibodies in vaccinated cattle, on day 60 for A. centrale and on either occasion for B. bovis. The reaction to the inoculation of B. bigemina S1A strain appears to lag behind the reaction to B. bovis R1A strain. It is not certain if this is a normal reaction to this B. bigemina strain or the result of interaction with the B. bovis strain. 相似文献
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AA Ovchinnikov VE Tsvettsikh BA Berdichevski? VN Lykov VR Suktanbaev AV Murychev 《Canadian Metallurgical Quarterly》1996,20(4):7-9
Through TCD test, observation on the blood flow dynamics change before and after treatment with 31 cases of the child cerebral atrophy was made. It is found that scalp therapy is able to speed up the blood flow of part artery, especially increase the even blood flow speed of MCA, ACA obviously (P < 0.05), which preliminary shows the mechanism of scalp therapy for child cerebral atrophy mean while. It is found that scalp therapy also has the function to restrain epilepsy. 相似文献
4.
VA Khil'ko VR Gofman AT Grechko LA Glaznikov IuA Shulev 《Canadian Metallurgical Quarterly》1997,(3):35-37
This paper presents the information on the early period of an explosive head trauma and trauma to the auditory system. Different types of hearing impairment, the staging of the pathological process were determined along with various immunological and biochemical changes occurring in this group of patients. The results of the study call for necessity of the early ENT observation of all patients in whom an explosive trauma is suspected. 相似文献
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We present a method for unified statistical analysis of short and long range correlations between various nucleotides in genomic DNA strands. The approach is based on the mutual study of Fourier structure factor spectra and pair correlation functions. The analysis of cross correlations in the different ranges of structural spectra permits identification of the main sources of correlations, namely, the coherent point mutations, coincident periodicities or large scale density variations. The technique for assessment of structural coupling between various genes in the genome is also described. 相似文献
8.
The influenza virus hemagglutinin (HA) contains three highly conserved cysteine residues at positions 551, 559, and 562 close to the carboxyl-terminus of the HA2 subunit which serve as palmitylation sites. Wild-type HA of influenza virus A/FPV/Rostock/34 (H7N1) and HA permutated by exchange of the acylated cysteine to serine residues were expressed in CV-1 cells by a SV40 vector system. Since density of immunostained HA on the cell surface measured by flow cytometric analysis did not differ between wild-type and acylation mutants, it was possible to compare acylation mutants and wild-type HA for their capacity to induce membrane fusion at low pH. The following observations were made: (1) lateral diffusion of a lipid-like fluorophore (R-18) from the erythrocyte membrane to the plasma membrane of cells expressing HA on the surface occurred equally well with mutants and wild type. (2) Diffusion of a low-molecular-weight fluorescent water-soluble probe (calcein) from erythrocytes into the cytoplasm of HA-expressing cells was not altered either. (3) However, depending on the position and the number of the deleted acylation sites, the mutants showed a reduced ability to induce syncytia. The data indicate that deacylation of the cytoplasmic tail has no measurable effect on the capacity of HA to induce membrane fusion and pore formation but that it suppresses syncytia formation. 相似文献
9.
Studies were conducted to assess the utility of free solution capillary electrophoresis (CE) for monitoring the effects of selected excipients on the thermal denaturation of a model protein (Ribonuclease A, RNase A) at low pH. Thermal denaturation/unfolding experiments were conducted via temperature-controlled CE using a run buffer of 20 mM citric acid in the pH range of 2.3-3.1, with a marker peptide incorporated to correct for temperature-induced changes in endoosmotic flow. The effects of selected excipients on the thermal unfolding of RNase A were then evaluated by adding either sorbitol, sucrose, polyethylene glycol 400 (PEG 400) or 2-methyl-2,4-pentanediol (MPD) to the electrophoretic run buffer (pH 2.3). Confirmatory denaturation experiments were conducted under the same solution conditions using circular dichroism (CD) spectropolarimetry. Using temperature-controlled CE, an increase in solution pH from 2.3 to 2.7 and 3.1 resulted in an increase in transition temperatures of RNase A by approximately 8 and 13 degrees C, respectively. Similar shifts in transition temperatures were observed when thermal denaturation transitions were monitored by far-UV CD. Sorbitol (0.55-1.1 M) and sucrose (0.55 M) each shifted the denaturation transition temperatures of RNase A to higher values, whereas PEG 400 and MPD had minimal effect on the unfolding transition midpoint at the concentrations evaluated (0.55 M for each). The observed changes in the transition temperatures for RNase A as a function of pH and selected excipients were similar when measured by either CE or far-UV CD. These results support the utility of CE for monitoring the effects of neutral excipients on the thermal denaturation of a model protein under selected conditions. The widespread utility of the technique may be limited by the narrow temperature range of most commercial CE instruments and the need to use extreme pH conditions to monitor the complete denaturation transition. 相似文献
10.
Functional overload (FO) of a muscle by removing its synergists results in a compensatory hypertrophy of the muscle. However, the extent of the response appears to be dependent, at least in part, on the activity and/or loading levels of the muscle following surgery. Thus, differences in the inherent physical activity levels across species may be an important factor to consider. In the present study, the effects of 8 weeks of FO on the isometric mechanical properties of the plantaris of mice (highly active) were determined and the findings compared with the results from previous studies performed on the plantaris of rats (highly active) and cats (less active). FO resulted in approximately a doubling of the mass, the physiological cross-sectional area and the maximum tetanic tension per unit cross-sectional area, was similar in the plantaris of control and FO mice. Isometric twitch speed properties were unaffected, but the tension enhancement in response to an increase in the rate of stimulation showed the pattern of a "faster" muscle following FO. The fatigue resistance of the plantaris in FO mice was significantly higher than in control mice. Although the degree of hypertrophy that occurred in the mouse plantaris was similar to that observed after FO in rats and in cats that are exercised intermittently at high intensities, there were differences in the mechanical properties that may be related to the adaptability of species and/or the behavioral responses to the overload. 相似文献