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2.
Summary A new method of quantification of the acid phosphatase activity assay by means of laser rays along with spectrography and photometry is described. Calculated S values, representing differences between densities of the spectral bands corresponding to Pb and Ag account for the amount of acP activity.The presented laser method enables a relative evaluation of the acP activity in a given region, yielding results which can be objectively expressed by figures.A special advantage of the presented method is, that it allows to compare the individual acP activities in different regions of the investigated organ, which may be of importance for the quantitative chemoarchitectonic of the brain. 相似文献
3.
Direct sequencing of the mitochondrial displacement loop (D-loop) of shrews
(genus Sorex) for the region between the tRNA(Pro) and the conserved
sequence block-F revealed variable numbers of 79-bp tandem repeats. These
repeats were found in all 19 individuals sequenced, representing three
subspecies and one closely related species of the masked shrew group (Sorex
cinereus cinereus, S. c. miscix, S. c. acadicus, and S. haydeni) and an
outgroup, the pygmy shrew (S. hoyi). Each specimen also possessed an
adjacent 76-bp imperfect copy of the tandem repeats. One individual was
heteroplasmic for length variants consisting of five and seven copies of
the 79-bp tandem repeat. The sequence of the repeats is conducive to the
formation of secondary structure. A termination-associated sequence is
present in each of the repeats and in a unique sequence region 5' to the
tandem array as well. Mean genetic distance between the masked shrew taxa
and the pygmy shrew was calculated separately for the unique sequence
region, one of the tandem repeats, the imperfect repeat, and these three
regions combined. The unique sequence region evolved more rapidly than the
tandem repeats or the imperfect repeat. The small genetic distance between
pairs of tandem repeats within an individual is consistent with a model of
concerted evolution. Repeats are apparently duplicated and lost at a high
rate, which tends to homogenize the tandem array. The rate of D- loop
sequence divergence between the masked and pygmy shrews is estimated to be
15%-20%/Myr, the highest rate observed in D-loops of mammals. Rapid
sequence evolution in shrews may be due either to their high metabolic rate
and short generation time or to the presence of variable numbers of tandem
repeats.
相似文献
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大鼠胼胝体内神经肽Y免疫反应阳性纤维的发育 总被引:1,自引:0,他引:1
本实验用免疫组织化学ABC法研究了大鼠胼胝体内神经肽Y免疫反应阳性(NPY-IR)纤维的生后发育。结果发现,许多NPY-IR纤维在大鼠出生时便存在于胼胝体内。NPY-IR胼胝体纤维的密度在生后1周内继续逐渐增高,在第2周内达到最高峰。之后,NPY-IR胼胝体纤维的密度逐渐下降,至第3周末时接近成年时的水平,即仅有少量NPY-IR纤维存在于胼胝体内。这些结果提示在大鼠早期生后发育过程中许多NPY-IR胼胝体纤维是暂时性的,其作用可能与大脑皮质的机能发育有关。 相似文献
6.
M B Kozik 《Folia histochemica et cytochemica》1978,16(1):31-36
The histotopography of metal contents was studied in brains from cases with arteriosclerotic dementia by means of laser spectrography, a technique which is both highly secific and sensitive. All the affected brains contained considerable amounts of calcium which was present in almost all brain regions. The quantitative evaluation showed twice as much calcium in the striatum relative to the cerebellar white matter. 相似文献
7.
The histoenzymic pattern of oxidative enzymes (G-6-PDH, G-PDH, ICDH, SDH, HBDH, NADH-2:tetrazolium dehydrogenase) was investigated in the developing neuroglia of rabbit brains, with special regard to the period of myelinogenesis. The obtained results lead to following conclusions: (1) During the early period of postnatal development there is maximal oxidative enzyme activity in ependymal cells, somewhat less reactive are the undifferentiated matrix cells and the differentiating cells of the mantle layer. No distinction can be made between the response of spongio- and neuroblasts. (2) Distinctly increased oxidoreductase activity, as compared to the early period of postnatal development, is demonstrated by the differentiating cells of myelination gliosis, no prevalence being demonstrable for enzymes of the particular metabolic pathways (pentose shunt, glycolysis or Krebs cycle). (3) G-6-PDH, G-PDH and oxidoreductases acting within the citric acid cycle are demonstrable only in single cells of the interfascicular oligodendroglia of adult rabbit brains, while almost all cells exhibit appreciable activity of HBDH and NADH-2 tetrazolium dehydrogenase. 相似文献
8.
Brodsky V. Y. Zolotarev Y. A. Malchenko L. A. Andreeva L. A. Lazarev D. S. Butorina N. N. Kozik V. S. Myasoedov N. F. 《Russian Journal of Developmental Biology》2020,51(2):99-105
Russian Journal of Developmental Biology - To clarify the organizing effect of Semax and HLDF-6 peptides on the kinetics of protein synthesis in hepatocytes, in addition to an in vitro study... 相似文献
9.
Zolotarev Yu. A. Dadayan A. K. Kozik V. S. Nagaev I. Yu. Azev V. N. Gorbunova E. Yu. Mustaeva L. G. Bogachouk A. P. Lipkin V. M. Myasoedov N. F. 《Russian Journal of Bioorganic Chemistry》2020,46(6):1044-1051
Russian Journal of Bioorganic Chemistry - The HLDF-6 hexapeptide corresponded to the 41–46 (TGENHR) fragment of the Human Leukemia Differentiation Factor (HLDF) and exhibited a wide spectrum... 相似文献
10.