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201.
A facile chemical synthesis of 1,2-dioleoyl and 1,2-dimyristoyl-sn-glycero-3-phospho-L-serine as well as the synthesis of several deuterated derivatives of phosphatidylserine (2 and 3 positions of serine and in the 3-glycerol position) are described. 360 MHz 1H NMR spectra of phosphatidylserine and the optical activity of various phosphatidylserine diastereomers were measured. 相似文献
202.
J S Altman J Kien 《Proceedings of the Royal Society of London. Series B, Containing papers of a Biological character. Royal Society (Great Britain)》1979,205(1159):209-227
The projections of nerves 6 and 7 of the locust suboesophageal ganglion (SOG) were stained by axonal filling with cobalt chloride. Nerve 6 contains two motoneurons which innervate neck muscles 50 and 51. Sensory neurons innervating hairs on the dorso-occipital region of the head also enter the ganglion through nerve 6 and terminate in a small bilateral plexus. The projections of the head hairs in nerve 6 do not overlap the arborizations of the motoneurons or the neurons of nerve 7, but lie in the same area as descending sensory neurons from wind-sensitive hairs of the front of the head. One branch of nerve 7 (7B) contains two fibres which innervate the salivary gland. These 'salivary' neurons (labelled SN1 and SN2) have their cell bodies in the ganglion. The second branch, 7A, contains sensory neurons from the submentum of the labium, which form four sensory plexuses, two dorsal and two ventral. The sensory plexuses from the submentum have specific regions of overlap with the salivary neurons and with the neck muscle motoneurons. We interpret these as indicating a flow of information from labial receptors signalling head and mouthpart movement to neurons involved in salivation and head movement. We further postulate that the anatomical separation of the various sensory plexuses is indicative of functional localization within the ganglion. 相似文献
203.
l-(+)-Bornesitol was detected in 23 of 33 genera of Gentianaceae investigated. The only subtribe without l-(+)-bornesitol (3 species tested) was Exacinae. None of the five genera of Menyanthaceae examined were found to contain l-(+)-bornesitol. 相似文献
204.
A novel reaction of S-adenosyl-L-methionine correlated with the activation of pyruvate formate-lyase
Joachim Knappe Thomas Schmitt 《Biochemical and biophysical research communications》1976,71(4):1110-1117
Conversion of the inactive form of pyruvate formate-lyase to the catalytically active enzyme is accomplished by the Fe-dependent ‘enzyme II’; reduced flavodoxin, S-adenosyl-L-methionine and the effector pyruvate are required. It was found that adenosylmethionine is reductively processed during activation of pyruvate formate-lyase to yield methionine, adenine and 5-deoxyribose. We suggest that transient adenosylation of enzyme II is required for its function as a converter enzyme. 相似文献
205.
Joachim Pohlmann 《Phytochemistry》1975,14(7):1587-1589
The cucurbitacins in roots of Bryonia dioica and B. alba have been investigated. Both species contain the cucurbitacins E, B, I, D, J, K and L, the dihydrocucurbitacins E and B, and tetrahydrocucurbitacin I. The detection of certain cucurbitacin aglycones depends upon the date of harvest, the duration of storage and the methods used for extraction. 相似文献
206.
207.
Prof. Dr. Manfred Gersch Heiner Birkenbeil Joachim Ude 《Cell and tissue research》1975,160(3):389-397
The prothoracic glands of the last instar of Galleria mellonella undergo characteristic alterations of their cellular fine structure closely related to cellular activity. During progressive secretory activity of the gland cells there are extensive plasmalemmal infoldings and formation of a pronounced lacunar system. Mitochondria of the active cell phase are characterized by a specific increase in size and paler colour of the matrix. In contrast to the alterations, nuclei, ER and Golgi cisterns do not undergo any submicroscopic changes during the different phases of cellular activity. The relationship between the substructural phenomena and the specific phases of cellular activity are discussed. 相似文献
208.
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
209.
210.