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991.
《Cell Stem Cell》2021,28(10):1790-1804.e8
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992.
993.
Pituitary β-endorphin content was measured in dormice during several distinct phases of the infradian body weight cycle. No significant differences in opiate content among groups were found. It appears unlikely that pituitary concentrations of β-endorphin have etiological significance in the development of spontaneous obesity in hibernators. 相似文献
994.
Abnormal long non-coding RNAs (lncRNAs) have been detected in esophageal squamous cell carcinoma (ESCC). Here, we focused on lncRNA ZNF667-AS1 and its downstream mechanism in ESCC progression. Differentially expressed lncRNAs in ESCC were predicted by bioinformatics analysis. ZNF667-AS1, microRNA-1290 (miR-1290), and prune homolog 2 with BCH domain (PRUNE2) expression was determined with their relationship in cell biological processes analyzed also by means of gain- and loss-of-function assays. Xenograft mouse models were performed to re-produce the in vitro findings. We found a decline in ZNF667-AS1 expression in ESCC tissues and cell lines. ZNF667-AS1 overexpression indicated a favorable prognosis of ESCC sufferers. ZNF667-AS1 overexpression suppressed ESCC cell malignant potentials. ZNF667-AS1 reduced miR-1290 to result in upregulation of the miR-1290 target gene PRUNE2. The inhibiting property of ZNF667-AS1 on the malignant characteristics of ESCC cells was achieved by disrupting the miR-1290-mediated downregulation of PRUNE2. ZNF667-AS1 suppressed the tumorigenesis of ESCC in vivo. Collectively, our study demonstrates that ZNF667-AS1 can function as a tumor suppressor in ESCC by upregulating PRUNE2 and downregulating miR-1290. 相似文献
995.
Previously, we have demonstrated the effects of exogenously administered opiates on somatostatin release in dogs and therefore the present study was designed to determine the effect of endogenous opiates via naloxone-induced opiate receptor blockade on somatostatin release. Additionally, plasma insulin and pancreatic polypeptide (PP) levels were determined in response to intragastrically instilled protein, carbohydrate and fat test meals in a group of eight conscious dogs. To all test meals either naloxone (4 mg) or saline was added. The rise of plasma somatostatin levels in response to liver extract, sucrose and fat was attenuated significantly by naloxone. Naloxone had no effect on the rise of postprandial plasma insulin and PP levels. The present data demonstrate that endogenous opiates have a stimulatory effect on postprandial somatostatin release in dogs which indicates a tight interaction that might be of relevance for nutrient homeostasis. 相似文献
996.
997.
《Archives of animal nutrition》2013,67(1):82-85
Nitrogen balances (six days) were determined in male Wistar rats during feeding a diet with sufficient protein or a nearly protein-free diet (n = 2×24), and then during three days of starvation (n = 2×12). The objective was to evaluate the effect of protein withdrawal on minimum nitrogen excretion in urine (UN), corresponding to endogenous UN, during feeding and subsequent starvation periods. The rats fed the protein free-diet had almost the same excretion of urinary N during feeding and starvation (165 and 157 mg/kg W0.75), while it was 444 mg/kg W0.75 in rats previously fed with protein, demonstrating a major influence of protein content in a diet on Nexcretion during starvation. Consequently, the impact of former protein supply on Nlosses during starvation ought to be considered when evaluating minimum N requirement necessary to sustain life. 相似文献
998.
This paper examines the sensitivity of endogenous bursters to a brief input pulse. The interneurons of the lobster cardiac ganglion were selected as a case study.Using a mathematical model specifically developed for the neurons in the cardiac ganglion of the lobster (Av-Ron et al., 1993), we show a tight link between burst characteristics and certain other parameters. We show that cells with different burst properties differ in their sensitivity to an input of a brief pulse.Irrespective of these differences, all cells display a bimodal response to a brief pulse applied during the quiescent period. During the first three-quarters of the quiescent period, they respond by producing a single spike at most. During the remaining one-quarter, the brief pulse can initiate the cells' intrinsic burst. Our predictions fit experimental results obtained by Tazaki and Cooke (1979).The results obtained herein are discussed with respect to fault tolerance considerations. 相似文献
999.
1000.
《Cell Stem Cell》2021,28(9):1566-1581.e8
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