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This review summarizes recent work that focuses on the role of endogenous opioids (EOs) and opiate receptors in the control of food intake. Although the anorexic effect of opiate antagonists are now well accepted, the exact EO, site(s), and mechanism(s) of action remain to be established. However, accumulating evidence suggests that dynorphin, an endogenous ligand for kappa-type opiate receptors, is an important regulator (stimulant) of appetite. The roles of other EOs, such as beta-endorphin, are less clear. EOs appear to be involved in maintaining normal feeding behavior and are likely responsible for the overconsumption of fat in genetically obese and stressed subjects. Opiate antagonists block overconsumption of palatable foods, thus offering a promising approach to weight reduction for some overweight individuals. Anorexias may follow from a deficiency of kappa-type opioid activity, and surprisingly, can also result from excess opioid activity. Indeed, opiate antagonists of the mu type (naloxone) can enhance eating and weight gain in certain anorexic conditions. Therefore, it appears that excess opioid agonist activity may result in hyperphagia or anorexia (depending on the opiate receptor type). Finally, opiate antagonists may help normalize both types of pathological feeding states. 相似文献
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Comparative study of Helicobacter pylori eradication rates of concomitant therapy vs modified quadruple therapy comprising proton‐pump inhibitor,bismuth, amoxicillin,and metronidazole in Korea 下载免费PDF全文
85.
Choi Jae Woong Yim Sung Sun Jeong Ki Jun 《Applied microbiology and biotechnology》2018,102(2):873-883
Applied Microbiology and Biotechnology - Beyond its traditional role as an L-amino acid producer, Corynebacterium glutamicum has recently received significant attention regarding its use in the... 相似文献
86.
Paclobutrazol [(2RS,3RS)-1-(4-chlorophenyl)methyl-4,4-dimethyl-2-(1h-1,2,4-trizol-1-yl)penten-3-ol] effectively decreased vegetative growth of rice
(Oryza sativa L.) seedlings and increased the chlorophyll content. The number of veins in a leaf, the calculated number of stomata per
leaf, and the length of guard cells were not altered by the paclobutrazol treatment, suggesting an effect on cell elongation.
The allocation pattern of carbohydrates was changed by either gibberellin (GA) or paclobutrazol treatment. GA3 induced more shoot growth and less accumulation of starch than the control and paclobutrazol-treated seedlings. Photosynthetic
ability was not affected by either paclobutrazol or GA3 treatment. Paclobutrazol-treated plants allocated a smaller amount of photosynthates for vegetative shoot growth and stored
more as starch in the crowns than the control and GA3-treated plants. The same starch degrading activity in the crown tissue of paclobutrazol-treated seedlings as in control plants
suggests that the accumulated starch is utilized in a normal activity for growth including leaf emergence, tiller formation,
and root production, resulting in improved seedling quality.
Received May 30, 1996; accepted December 10, 1996 相似文献
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Temporal and spatial transcriptomic and microRNA dynamics of CAM photosynthesis in pineapple 下载免费PDF全文
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Tu Cam Le Chae-Yoon Yim Songhee Park Nikita Katila Inho Yang Myoung Chong Song Yeo Joon Yoon Dong-Young Choi Hyukjae Choi Sang-Jip Nam William Fenical 《Bioorganic & medicinal chemistry letters》2017,27(14):3123-3126
HPLC-UV guided isolation of the culture broth of a marine bacterium Saccharomonospora sp. CNQ-490 has led to the isolation of two new natural products, lodopyridones B and C (1 and 2) along with the previously reported lodopyridone A (3). Their chemical structures were established from the interpretation of 2D NMR spectroscopic data and the comparison of NMR data with the lodopyridone A (3). Lodopyridones B and C (1 and 2) possess the thiazole, and chloroquinoline groups which are characteristic features of these molecules. Lodopyridones A–C show weak inhibitory activities on the β-site amyloid precursor protein cleaving enzyme 1 (BACE1). 相似文献