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951.
Jack Feehan Nicholas Tripodi Sarah Fraser Kathleen Mikkelsen April Thewlis Dimitrios Kiatos Maja Husaric Vasso Apostolopoulos 《Journal of biophotonics》2020,13(3)
This study investigates the immunomodulatory effects of polychromatic polarized light therapy (PLT) on human monocyte cells. While there is some evidence demonstrating a clinical effect in the treatment of certain conditions, there is little research into its mechanism of action. Herein, U937 monocyte cells were cultured and exposed to PLT. The cells were then analyzed for change in expression of genes and cell surface markers relating to inflammation. It was noted that 6 hours of PLT reduced the expression of the CD14, MHC I and CD11b receptors, and increased the expression of CD86. It was also shown that PLT caused downregulation of the genes IL1B, CCL2, NLRP3 and NOD1, and upregulation of NFKBIA and TLR9. These findings imply that PLT has the capacity for immunomodulation in human immune cells, possibly exerting an anti‐inflammatory effect. 相似文献
952.
Availability and utilization of fertilizer nitrogen by rice under alternate flooding 总被引:1,自引:0,他引:1
Summary A greenhouse pot experiment with three N sources—15N-depleted ammonium sulfate, urea and sulfur-coated urea (SCU), three N levels—0, 50 and 200 ppm, and three irrigation treatments
was conducted with rice in an Alamo clay soil. The irrigation treatments consisted of continuous flooding, alternating flooded-saturated
and alternating flooded-drained conditions. The kinetics of NH
4
+
and NH
4
+
+NO
3
−
(available N) in soil was investigated under rice culture.
Alternating flooded-drained conditions maintained a significantly lower level of available N in the soil than the other irrigation
treatments. Among the N sources evaluated, urea and A/S had similar effects but SCU maintained significantly lower levels
of available N in the soil during the growth of rice. Appreciable quantities of NO
3
−
accumulated during the draining periods of alternating flooded-drained treatments were apparently lost from the soil system
upon reflooding. 相似文献
953.
Genetic counselling in Down's syndrome 总被引:4,自引:0,他引:4
954.
955.
K Keydorn E Damsgaard N Horn M Mikkelsen I Tygstrup S Vestemark J Weber 《Humangenetik》1975,29(2):171-175
The distribution of copper among the organs of an aborted, male foetus, expected to develop Menkes' syndrome, was entirely different from the distribution in 4 normal foetuses. Copper concentrations determined by neutron activation analysis showed a considerably reduced content in the liver, but increased concentrations in the other organs analysed; total foetal copper was normal. 相似文献
956.
Wolfgang Knecht Nils Egil Mikkelsen Anders Ranegaard Clausen Hans Eklund Jure Piškur 《Biochemical and biophysical research communications》2009,382(2):430-433
Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK) can additionally sensitize human cancer cell lines towards the anti-cancer drug gemcitabine. We show that this property is based on the Dm-dNK ability to efficiently phosphorylate gemcitabine. The 2.2 Å resolution structure of Dm-dNK in complex with gemcitabine shows that the residues Tyr70 and Arg105 play a crucial role in the firm positioning of gemcitabine by extra interactions made by the fluoride atoms. This explains why gemcitabine is a good substrate for Dm-dNK. 相似文献
957.
Summary Prostaglandins and inhibitors of prostaglandin synthesis have striking regulatory effects on intestinal muscularis externa. We suggested earlier that a population of macrophage-like cells, located between the external muscle layers might release prostaglandins with a local effect on enveloping interstitial cells of Cajal, postulated pacemaker cells of the gut.To determine cellular production site(s) of prostaglandin we applied monoclonal antibodies against prostaglandin H synthase combined with the PAP technique to sections of rabbit and guinea-pig small intestine and kidney. In rabbit small intestine muscle cells in the circular muscle layer and in the muscularis mucosae were positive, longitudinal muscle negative. Vascular endothelial cells and serosal mesothelial cells were stained. In guinea-pig all muscle layers were unstained but endothelial and mesothelial cells were stained together with unidentified cells in the outermost submucosa. In rabbit kidney, positive staining of collecting ducts, interstitial cells, the parietal layer of Bowman's capsule and arterial endothelial cells was present. Furthermore, we found prostaglandin synthase antigenicity in the epithelial cells lining the loop of Henle, not described before. In guinea-pig medullary collecting ducts were stained and the papilla was lined by stained epithelial cells.The results show a species variation in the distribution of recognizable levels of prostaglandin H synthase. The impressive reaction in the mesothelium must be considered, when enzyme distribution is examined biochemically with fractionated tissue. Our findings do not support our hypothesis that macrophage-like cells are more potent sources of prostaglandins than smooth muscle cells. 相似文献
958.
Summary The distribution of tyrosine hydroxylase (TH)- and neuropeptide Y (NPY)-immunoreactive(IR) nerve fibers in the pineal complex was investigated in untreated rats and rats following bilateral removal of the superior cervical ganglia. In normal animals, a large number of TH- and NPY-IR nerve fibers were present in the pineal capsule, the perivascular spaces, and intraparenchymally between the pinealocytes throughout the superficial pineal and deep pineal gland. A small number of TH-IR and NPY-IR nerve fibers were found in the posterior and habenular commissures, a few fibers penetrating from the commissures into the deep pineal gland. To elucidate the origin of these fibers, the superior cervical ganglion was removed bilaterally in 10 animals, and the pineal complex was examined immunohistochemically. Two weeks after the ganglionectomy, the TH-IR and NPY-IR nerve fibers in the superficial pineal gland had almost completely disappeared. On the other hand, in the deep pineal and the pineal stalk, the TH-IR and NPY-IR fibers were still present after ganglionectomy. These data show that the deep pineal gland and the pineal stalk possess an extrasympathetic innervation by TH-IR and NPY-IR fibers. It is suggested that the extrasympathetic TH-IR and NPY-IR nerve fibers innervating the deep pineal and the pineal stalk originate from the brain. 相似文献