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1.
Electron beam relaxation in plasma under conditions typical of laboratory plasma devices based on a steady-state beam-plasma discharge was investigated. It is shown that the measured dependences of the beam loss factor in a discharge operating at a moderately low gas pressure disagree with theoretical dependences calculated for a longitudinally uniform plasma. Analytic dependences obtained in the framework of quasilinear theory with allowance for longitudinal plasma inhomogeneity agree with experimental data. Some effects caused by the influence of the main discharge parameters on electron beam relaxation are analyzed.  相似文献   
2.
The need for selection of the optimal material for the manufacturing of cardio-patches can be resolved by the use of cryostored autologous pericardial tissue. This short communication is a concise fragment of a large-scale research and demonstrates only the efficiency of cell culturing before and after pericardial preservation in the low temperature conditions.  相似文献   
3.
The proliferative response of lymphocytes to mitogens was studied in 17 patients according to 3H-thymidine incorporation. The patients had high sensitivity to timothy pollen, confirmed by the allergological anamnesis, skin tests, and the presence of allergen-specific IgE-antibodies. Mononuclears of peripheral blood were cultivated with a lipopolysaccharide (LPS) to study the response to the polyclonal B cell activator, while with PHA to study the response of T cells over 7 days. The patients with pollinosis manifested increased spontaneous cell proliferation. The degree of the proliferative response of the cells to LPS and PHA was similar in patients and normal subjects. It is suggested that the magnitude of spontaneous proliferation influences the degree of the mitogenic response of B cells.  相似文献   
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A continuous-flow NMR culture system for mammalian cells has been developed on which 31P-NMR experiments under complete and strictly physiologic conditions have been performed. Observations on the response of the cellular metabolism to stresses such as starvation, low temperature and changes in environmental pH monitored by 31P-NMR are reported. The response of the intracellular pH relative to the external pH of the growth medium is studied. We find that under the experimental conditions used there exists a ΔpH varying between less than 0.2 and more than 0.6 pH units. These results are compatible with those obtained using other techniques.  相似文献   
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Summary Using cloned cDNA for human 2-macroglobulin (A2M) as a probe, mink-Chinese hamster hybrid cells were analysed. The results allowed us to assign a gene for A2M to mink chromosome 9. Breeding tests demonstrated that the Lpm-locus coding for other related -macroglobulin protein and the gene for peptidase B (PEPB) are linked 11±3 cm apart. The PEPB gene is located on mink chromosome 9, and hence, the Lpw-locus is on the same mink chromosome. The relationship of the genetic systems controlling the isotypically different -macroglobulins in mink serum are discussed.  相似文献   
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To expand the mink map, we established a new panel consisting of 23 mink-mouse clones. On the basis of statistical criteria (Wijnen et al. 1977; Burgerhout 1978), we developed a computer program for choice of clones of the panel. Assignments of the following mink genes were achieved with the use of the hybrid panel: glyoxalase (GLO), Chromosome (Chr) 1; acetyl acylase (ACY), Chr 5; creatine phosphokinase B (CKBB), Chr 10; alcohol dehydrogenase-2 (subunit B) (ADH2), Chr 8. Using a series of clones carrying rearrangements involving mink Chr 1 and 8, we assigned the gene for ME1 to the short arm of Chr 1 and that for ADH2 to Chr 8, in the region 8p12-p24. Mapping results confirm the ones we previously obtained with a mink-Chinese hamster panel. However, by means of an improved electrophoretic technique, we revised the localization of the gene for purine nucleoside phosphorylase (NP), which has been thought to be on mink Chr 2. It is reassigned to mink Chr 10.  相似文献   
10.
The results of genetic study on linkage of Lpm locus with peptidase B gene are presented. Investigation of 111 offspring back-crosses shows that Lpm allotypes and allelic variants of peptidase B are inherited in concert. The frequency of recombination between the Lpm locus and peptidase B gene is 11 +/- 3% in male. Since it was earlier established that peptidase B gene is a marker of chromosome 9, our data indicate that the Lpm loci family is situated in the chromosome 9 of domestic mink.  相似文献   
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