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41.
The present study was performed to examine the central effects of antidepressants on nociceptive jaw opening reflex after intracisternal injection. we also investigated the mechanisms of central antinociceptive action of intracisternal antidepressants. We recorded the jaw opening reflex in freely moving rats and chose to administer antidepressants intracisternally in order to eliminate the effects of anesthetic agents on the pain assessment and evaluate the importance of the spinal site of action of antidepressants. After intracisternal injection of 15 microg imipramine, digastric electromyogram (dEMG) was decreased to 76+/-6% of the control. Intracisternal administration of 30 microg desipramine, nortriptyline or imipramine suppressed dEMG remarkably to 48+/-2, 27+/-8, or 25+/-5% of the control, respectively. The suppression of dEMG was maintained for 50 min. L-NG-Nitroarginine methyl ester (NAME) blocked the suppression of dEMG from 32+/-2 to 81+/-5% of the control. These results indicate that antidepressants produce antinociception through central mechanisms in the orofacial area. The central NO pathway seems to be involved in the antinociception of intracisternal antidepressants at supraspinal sites. 相似文献
42.
Independent risk factors for new coronary events in older African-American men were (1) age (risk ratio = 1.037), (2) cigarette smoking (risk ratio = 2.231), (3) hypertension (risk ratio = 2.531), (4) serum total cholesterol (risk ratio = 1.012), (5) serum high-density lipoprotein (HDL) cholesterol (inverse association) (risk ratio = 0.948), and (6) prior coronary artery disease (CAD) (risk ratio = 2.288). Independent risk factors for new coronary events in older African-American women were (1) cigarette smoking (risk ratio = 2.202), (2) hypertension (risk ratio = 2.344), (3) diabetes mellitus (risk ratio = 1.632), (4) serum total cholesterol (risk ratio = 1.008), (5) serum HDL cholesterol (inverse association) (risk ratio = 0.936), (6) age (risk ratio = 1.026), and (7) prior CAD (risk ratio = 2.368). 相似文献
43.
BACKGROUND: Although transmission of hepatitis C virus (HCV) through parental exposure is well documented, it is still controversial whether familial clustering of HCV occurs. METHODS: To investigate risk factors for HCV infection, 109 cases and 84 non-infected controls were studied. In addition, 250 family members (104 men, 146 women) of cases and 170 family members of controls (64 men, 106 women) were tested for HCV infection using an anti-HCV antibody, alanine aminotransferase (ALT), and reverse transcribed polymerase chain reaction (RT-PCR). RESULTS: In the case-control analysis, people aged > or =60 were almost three times more likely to be infected by HCV than those aged <40. Risk of HCV infection was most strongly related to a history of blood transfusion (OR = 12.6, 95% CI: 4.3-36.5) followed by a history of jaundice (OR = 4.1, 95% CI: 1.3-12.6). Only one family member of cases and no-one related to the controls had HCV infection. CONCLUSIONS: These results suggest that, in Korea, age and parenteral exposure, such as a blood transfusion, are risk factors for HCV infection and familial clustering of HCV infection, if it occurs, is rare. 相似文献
44.
The problem of packing circles into a domain of prescribed topology is considered. The circles need not have equal radii. The Collins-Stephenson algorithm computes such a circle packing. This algorithm is parallelized in two different ways and its performance is reported for a triangular, planar domain test case. The implementation uses the highly parallel graphics processing unit (GPU) on commodity hardware. The speedups so achieved are discussed based on a number of experiments. 相似文献
45.
Kang Ji-Hoon Hwang Jinyul Sung Hyung Jin Ryu Hoon 《The Journal of supercomputing》2021,77(9):9597-9614
The Journal of Supercomputing - Direct numerical simulations (DNS) of turbulent flows have increasing importance because they not only provide fundamental understanding of turbulent flows but also... 相似文献
46.
Neural Computing and Applications - In recent years, the design of social software UI has become a design research focus in the field of design. Color affects many factors in UI design. However,... 相似文献
47.
Durai Mani Kumaravel Sakthivel Mukannan Arivanandhan Krishnakumar Balu Thiripuranthagan Sivakumar Ahn Young-Ho 《Journal of Porous Materials》2021,28(6):1907-1917
Journal of Porous Materials - Valeric acid can be produced by selective hydrogenation of biomass-derived levulinic acid. The present work aims to synthesize ethyl valerate (EV), a fuel, fuel... 相似文献
48.
Nguyen Khanh Toan Nguyen Chi Tai Soo-A Kim Sang-Gun Ahn 《International journal of molecular sciences》2021,22(1)
Salivary gland dysfunction induces salivary flow reduction and a dry mouth, and commonly involves oral dysfunction, tooth structure deterioration, and infection through reduced salivation. This study aimed to investigate the impact of aging on the salivary gland by a metabolomics approach in an extensive aging mouse model, SAMP1/Klotho -/- mice. We found that the salivary secretion of SAMP1/Klotho -/- mice was dramatically decreased compared with that of SAMP1/Klotho WT (+/+) mice. Metabolomics profiling analysis showed that the level of acetylcholine was significantly decreased in SAMP1/Klotho -/- mice, although the corresponding levels of acetylcholine precursors, acetyl-CoA and choline, increased. Interestingly, the mRNA and protein expression of choline acetyltransferase (ChAT), which is responsible for catalyzing acetylcholine synthesis, was significantly decreased in SAMP1/Klotho -/- mice. The overexpression of ChAT induced the expression of salivary gland functional markers (α–amylase, ZO-1, and Aqua5) in primary cultured salivary gland cells from SAMP1/Klotho +/+ and -/- mice. In an in vivo study, adeno-associated virus (AAV)-ChAT transduction significantly increased saliva secretion compared with the control in SAMP1/Klotho -/- mice. These results suggest that the dysfunction in acetylcholine biosynthesis induced by ChAT reduction may cause impaired salivary gland function 相似文献
49.
50.
Seungmin Ahn Hoyoung Jung Prof. Dr. Jung-Min Kee 《Chembiochem : a European journal of chemical biology》2021,22(2):319-325
Protein phosphorylation is one of the most studied post-translational modifications (PTMs). Despite the remarkable advances in phosphoproteomics, a chemically less-stable subset of the phosphosites, which we call the crypto-phosphoproteome, has remained underexplored due to technological challenges. In this Viewpoint, we briefly summarize the current understanding of these elusive protein phosphorylations and identify the missing pieces for future studies. 相似文献