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71.
L A Lark K B Becker R E Park J A Weyhenmeyer 《Canadian journal of physiology and pharmacology》1990,68(11):1432-1436
Four-week-old inbred Dahl salt-sensitive (DS/JR) and Dahl salt-resistant (DR/JR) rats were placed on an 8% salt diet with or without a supplemental 2.5% tryptophan (Trp). Blood pressures were monitored for the next 5 weeks. Urine volumes and ion concentrations were measured during the 6th week. Blood pressures of DS/JR rats on control diets elevated rapidly and markedly, whereas pressures of DS/JR rats on the Trp-supplemented diet were not significantly elevated over those of DR/JR rats. Pressures of DR/JR rats were unaffected by Trp supplementation. Urinary sodium was significantly greater in DR/JR rats compared with DS/JR rats and was unaffected by Trp supplementation. This suggests that the antihypertensive effect of Trp was not at the level of the kidney. We conclude that dietary Trp blocks the development of hypertension in DS/JR rats maintained on a high salt diet. 相似文献
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Selective-Differential Medium for Isolation and Differentiation of Pectinatus from Other Brewery Microorganisms 总被引:2,自引:2,他引:0 下载免费PDF全文
An agar medium, LL-agar (lactate-lead acetate) was designed to selectively differentiate members of the genus Pectinatus (S. Y. Lee, M. S. Mabee, and N. O. Jangaard, Int. J. Syst. Bacteriol. 28:582-594, 1978; S. Y. Lee, M. S. Mabee, N. O. Jangaard, and E. K. Horiuchi, J. Inst. Brew. 86:28-30, 1980) from other brewery microorganisms. Selectivity was achieved by the use of sodium lactate as the sole source of carbon and phenylethyl alcohol as an inhibitor for aerobic gram-negative bacteria and yeast. Differentiation was established by the introduction of lead acetate into the medium, which reacted with the H2S liberated by Pectinatus and resulted in a blackening of the Pectinatus colonies while the other brewery organisms, when present, remained white. In combination with the Lee tube (J. E. Ogg, S. Y. Lee, and B. J. Ogg, Can. J. Microbiol. 25:987-990, 1979) and this medium, isolation of Pectinatus organisms from beer samples was accomplished with convenience and simplicity. 相似文献
73.
F.F. Sun B.M. Taylor F.H. Lincoln O.K. Sebek 《Prostaglandins & other lipid mediators》1980,20(4):729-733
The transformation of 6-keto-PGF1α to two prostacyclin metabolites, 2,3-dinor-6-keto-PGF1α (I) and 2,3-dinor-6,15-diketo-13,14-dihydro-PGF1α (II) by UC-6176 is described. The finding that the bacterium oxidized 6-keto-PGF1α to the 6,15-diketo metabolite II shows that it contains 15-hydroxy prostaglandin dehydrogenase and Δ13 reductase enzyme systems. 相似文献
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A method which localizes labile 5% ethylene glycol-bis-(beta-amino-ethyl ether)N-N'-tetraacetic acid-removable calcium in spherules within hypertrophied chondrocytes and in pericellular matrix using alizarin red S (ARS) is described. Fresh blocks of epiphyseal cartilage approximately 1 mm thick were immersed into 0.5-2% ARS solution containing 7% mounted on glass slides in 7% sucrose or in glycerol-gelatin. The stained tissue blocks were also dehydrated in acetone, cleared in xylene and mounted in Preservaslide. The ARS precipitated ionic calcium as red Ca-ARS salt which was birefringent in polarizing microscope, stable in water at pH 4-9 and in nonpolar organic solvent but soluble in polar solvents, especially in dimethyl sulfoxide. In contrast, ARS-stained insoluble calcium phosphate was stable even in dimethyl sulfoxide. Calcium in the hypertrophied chondrocytes, therefore, was thought to be present in a readily ionizable state instead of as insoluble calcium phosphate. Since addition of 7% sucrose retained as well as improved ARS localization of cellular calcium, the calcium was believed to be present in an osmotically sensitive, membrane-bound cytoplasmic compartment. The ARS-positive labile calcium in spherules which develop in the hypertrophied chondrocytes as well as in the pericellular matrix at the zone of provisional calcification suggested a preparatory stage in the process of cartilage calcification. 相似文献
76.
Jiaming Tian Bingxin Dai Li Gong Pingping Wang Han Ding Siwei Xia Weice Sun Cuiping Ren Jijia Shen Miao Liu 《PLoS neglected tropical diseases》2022,16(8)
Schistosomiasis is a serious and widespread parasitic disease caused by infection with Schistosoma. Because the parasite’s eggs are primarily responsible for schistosomiasis dissemination and pathogenesis, inhibiting egg production is a potential approach to control the spread and severity of the disease. The bromodomain and extra-terminal (BET) proteins represent promising targets for the development of epigenetic drugs against Schistosoma. JQ-1 is a selective inhibitor of the BET protein family. In the present study, JQ-1 was applied to S. japonicum in vitro. By using laser confocal scanning microscopy and EdU incorporation assays, we showed that application of JQ-1 to worms in vitro affected egg laying and the development of both the male and female reproductive systems. JQ-1 also inhibited the expression of the reproductive-related genes SjPlk1 and SjNanos1 in S. japonicum. Mice infected with S. japonicum were treated with JQ-1 during egg granuloma formation. JQ-1 treatment significantly reduced the size of the liver granulomas and levels of serum alanine aminotransferase and aspartate aminotransferase in mice and suppressed both egg laying and the development of male and female S. japonicum reproductive systems in vivo. Moreover, the mRNA expression levels of some proinflammatory cytokines were decreased in the parasites. Our findings suggest that JQ-1 treatment attenuates S. japonicum egg–induced hepatic granuloma due at least in part to suppressing the development of the reproductive system and egg production of S. japonicum. These findings further suggest that JQ-1 or other BET inhibitors warrant additional study as a new approach for the treatment or prevention of schistosomiasis. 相似文献
77.
Shuai Ma Shuhui Sun Jiaming Li Yanling Fan Jing Qu Liang Sun Si Wang Yiyuan Zhang Shanshan Yang Zunpeng Liu Zeming Wu Sheng Zhang Qiaoran Wang Aihua Zheng Shuguang Duo Yang Yu Juan Carlos Izpisua Belmonte Piu Chan Qi Zhou Moshi Song Weiqi Zhang Guang-Hui Liu 《Cell research》2021,(4):415-432
Aging is a major risk factor for many diseases,especially in highly prevalent cardiopulmonary comorbidities and infectious diseases including Coronavirus Diseas... 相似文献
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