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951.
A Revision of the Cytology and Ontogeny of Several Deficiencies in the 3a1–3c6 Region of the X Chromosome of DROSOPHILA MELANOGASTER 下载免费PDF全文
The cytology and developmental attributes of 18 deficiency mutations in the 3A1–3C6 region of the salivary gland X chromosome of Drosophila melanogaster have been investigated. The cytological limits of several older deficiencies have been revised and clarified and several new deficiencies are characterized. The deficiency mutants, with one possible exception, show a lethal phase in the late embryonic period or the early first larval instar. In contrast, the earliest acting point mutation lethals exposed by these deficiencies generally exhibit a somewhat later, post-embryonic lethality, perhaps indicating that the deficiencies are having some cumulative or synergistic impact on development. However, even with this difference in time of lethality, it is still possible to conclude that it is not the absolute size of the deficiency but rather the character of the loci deleted that determines the impact on development. Observations on the morphology of lethal embryos shows that while this analysis is internally consistent, it does not agree with earlier work. None of the 3A1–3C6 deficiencies causes any major teratologies during embryogenesis. Furthermore, the "earliest acting" gene in this region does not lie in band 3C1 but is most likely associated with bands 3A8–10. 相似文献
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The Raman spectroscopic lines of liquid cultures of Rhizobium japonicum have been compared with electron microscopic examinations and growth measurements of these cells. The results showed that the significant Raman lines are related to the reproduction activities of the procaryotic cells. 相似文献
955.
ZAKβ antagonizes and ameliorates the cardiac hypertrophic and apoptotic effects induced by ZAKα 下载免费PDF全文
Chien‐Yao Fu Wei‐Wen Kuo Tsung‐Jung Ho Su‐Ying Wen Ling‐Chun Lin Yan‐Shen Tseng Hui‐Chuan Hung Vijaya Padma Viswanadha Chih‐Yang Huang 《Cell biochemistry and function》2016,34(8):606-612
ZAK (sterile alpha motif and leucine zipper containing kinase AZK), a serine/threonine kinase with multiple biochemical functions, has been associated with various cell processes, including cell proliferation, cell differentiation, and cardiac hypertrophy. In our previous reports, we found that the activation of ZAKα signaling was critical for cardiac hypertrophy. In this study, we show that the expression of ZAKα activated apoptosis through both a FAS‐dependent pathway and a mitochondria‐dependent pathway by subsequently inducing caspase‐3. ZAKβ, an isoform of ZAKα, is dramatically expressed during cardiac hypertrophy and apoptosis. The interaction between ZAKα and ZAKβ was demonstrated here using immunoprecipitation. The results show that ZAKβ has the ability to diminish the expression level of ZAKα. These findings reveal an inherent regulatory role of ZAKβ to antagonize ZAKα and to subsequently downregulate the cardiac hypertrophy and apoptosis induced by ZAKα. 相似文献
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Cerebral glucose metabolism is a reliable index of neural activity and may provide evidence for brain function in healthy adults. We studied the correlation between cerebral glucose metabolism and age under the resting-state in both sexes with position emission tomography. Statistical test of age effect on cerebral glucose metabolism was performed using the statistical parametric mapping software with a voxel-by-voxel approach ( family wise error corrected, -voxel threshold). The subjects consisted of 108 females (mean S.D. = 4510 years) and 126 males (mean S.D. = 4911 years). We showed here that brain activity in the frontal and temporal lobes in both sexes decreased significantly with normal aging. The glucose metabolism in the caudate bilaterally showed a negative correlation with age in males, but not in females. Few regions in males were shown with an increased glucose metabolism with age. Although the mechanisms of brain aging are still unknown, a map of brain areas susceptible to age was described in this report. 相似文献
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