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321.
The use of modernized photometric accessories to a model microscope manufactured by the Leningrad Optico-Mechanical Amalgamation (USSR), as well as the practical application of innovations facilitating and standardizing research work, has made it possible to obtain objective data indicating the presence of significant, direct, linear correlation between infectious activity and the intensity of fluorescence emitted by fluorescent antibodies bound with the antigen of 11 studied variants of Japanese encephalitis virus in continuous cell lines. The study of the dynamics of fluorescence intensity permitted the objective evaluation of the previously revealed regularity in the increase of the intensity of the induced fluorescence of Japanese encephalitis antigen in continuous cell cultures. 相似文献
322.
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324.
L E Taplin J P Loveridge 《Comparative biochemistry and physiology. A, Comparative physiology》1988,89(3):443-448
1. Nile crocodiles, reared in fresh water and exposed acutely to seawater, suffer marked dehydration and hypernatraemia. Cloacal urine osmolarity and potassium concentration increased markedly but urine sodium remains low. 2. Hypernatraemia is increased when secretion from the lingual salt glands is prevented. 3. C. niloticus appears not to drink seawater. 4. Similarities in osmoregulatory response between estuarine and Nile crocodiles suggest that the lingual salt glands of C. niloticus are functional in salt water, playing an important role in sodium balance. 5. Significant differences in the function of the renal/cloacal complex of Alligator and Crocodylus emphasize further the differences between these two groups of crocodilian and provide support for the postulated marine ancestry of many or all of the Crocodylidae. 相似文献
325.
C López-Otin A O Grubb E Méndez 《Biochemical and biophysical research communications》1983,117(1):202-209
An apparently novel human plasma and urinary protein of low molecular weight was isolated from several highly purified preparations of protein HC by gel chromatography and high voltage electrophoresis with a yield of about 8 mg/g. The protein has a molecular weight of about 20,000, neutral electrophoretic mobility at pH 6.5 and a high content of half-cystine. It is associated with a yellow-brown chromophore like protein HC and could be demonstrated in all investigated preparations of isolated human, rabbit and guinea-pig protein HC and alpha 1-microglobulin. 相似文献
326.
Data are presented to show how the number and growth of juvenile salmon in streams in the Scottish Highlands are influenced by various physical (temperature, water chemistry, depth and velocity, type of substratum) and biotic (food resources, competition, recruitment) factors. 相似文献
327.
B cells in patients with X-linked agammaglobulinemia 总被引:19,自引:0,他引:19
M E Conley 《Journal of immunology (Baltimore, Md. : 1950)》1985,134(5):3070-3074
X-linked agammaglobulinemia (XLA) has been described as a disorder in which pre-B cells fail to differentiate into B cells. However, a small number of B cells have been seen occasionally in patients with this disorder. Because the phenotype of these cells might be helpful in defining the site of the defect in XLA, immunofluorescent staining techniques were used to characterize the B cells that can be found in patients with XLA. Surface IgM-positive B cells could be detected in the peripheral circulation of all seven patients studied. These B cells constituted a very small percentage of the total lymphocytes (0.01 to 0.3% compared with 3.2 to 13.7% in controls) and differed in phenotype from control B cells. They were much more brightly stained for surface IgM (p less than 0.001) and less brightly stained for Ia (p less than 0.01). This phenotype is similar to that described for immature B cells in the mouse. Over 80% of the patients' B cells expressed surface IgD, and all expressed the B cell marker B1, but only 35% expressed the B cell marker B2. This B cell marker, which is the C3d receptor and the Epstein-Barr virus receptor, is expressed later in ontogeny than B1 and can be detected on over 80% of control B cells. All B cells expressed either kappa or lambda light chain. These findings indicate that the defect in differentiation of pre-B cells into B cells is not absolute in patients with XLA. The immature phenotype of the B cells additionally suggests that there may be a block in the maturation of B cells at more than one stage of differentiation in this disorder. 相似文献
328.
N D Klimchuk M S Kitsara O M Frolova N M Balaeva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(2):41-45
Experiments on the laboratory cultures of lice infected by Weigl's method revealed that the spontaneous, erythromycin-resistant mutant of R. prowazekii strain E, adapted to the vector's organism, retained its resistance to erythromycin during 50 successive passages without the maintenance concentrations of this antibiotic. The above strain remained sensitive to tetracycline and levomycetin. Its level of sensitivity to the latter antibiotics was similar to that of R. prowazekii strains cultivated in the vector's organism for a long time. 相似文献
329.
S Kumar M Antony N K Mehrotra 《Biochemical and biophysical research communications》1984,125(3):967-973
Single cutaneous application of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) increased epidermal oxidised glutathione reductase activity in adult mouse by almost 100%. Pretreatment of animals with vitamin A for a week resulted in 75% inhibition of TPA induced change in the enzyme activity which remained unaffected in skin treated with vitamin A alone. This biochemical change in skin induced by TPA and modulated by vitamin A has been discussed in relation to epidermal hyperplasia. 相似文献
330.