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111.
A H Wang S Fujii J H van Boom A Rich 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(13):3968-3972
The deoxynucleotide fragment d(GpGpCpCpGpGpCpC) was synthesized and crystallized, and its three-dimensional structure was determined by x-ray diffraction techniques to a resolution of 2.25 A. The molecule forms a right-handed double helix in which the two base pairs at either end of the molecule are in the conventional A-DNA conformation, while the central four base pairs have a modified form in which alternate residues have sugar conformations that are closer to those in B-DNA than in A-DNA. The molecules have an intermolecular contact in which the planar terminal guanine . cytosine base pair lies on the flat minor groove surface of the A-DNA helix. 相似文献
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William T. Cefalu Andrew J.M. Boulton William V. Tamborlane Robert G. Moses Derek LeRoith Eddie L. Greene Frank B. Hu George Bakris Judith Wylie-Rosett Julio Rosenstock Katie Weinger Lawrence Blonde Mary de Groot Matthew C. Riddle Robert Henry Sherita Hill Golden Stephen Rich Lyn Reynolds 《Diabetes care》2015,38(7):1177-1180
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Anita Annaházi Richárd Róka András Rosztóczy Tibor Wittmann 《World journal of gastroenterology : WJG》2014,20(20):6031-6043
Irritable bowel syndrome (IBS) is a long-lasting, relapsing disorder characterized by abdominal pain/discomfort and altered bowel habits. Intestinal motility impairment and visceral hypersensitivity are the key factors among its multifactorial pathogenesis, both of which require effective treatment. Voltage-gated calcium channels mediate smooth muscle contraction and endocrine secretion and play important roles in neuronal transmission. Antispasmodics are a group of drugs that have been used in the treatment of IBS for decades. Alverine citrate, a spasmolytic, decreases the sensitivity of smooth muscle contractile proteins to calcium, and it is a selective 5-HT1A receptor antagonist. Alverine, in combination with simethicone, has been demonstrated to effectively reduce abdominal pain and discomfort in a large placebo-controlled trial. Mebeverine is a musculotropic agent that potently blocks intestinal peristalsis. Non-placebo-controlled trials have shown positive effects of mebeverine in IBS regarding symptom control; nevertheless, in recent placebo-controlled studies, mebeverine did not exhibit superiority over placebo. Otilonium bromide is poorly absorbed from the GI tract, where it acts locally as an L-type calcium channel blocker, an antimuscarinic and a tachykinin NK2 receptor antagonist. Otilonium has effectively reduced pain and improved defecation alterations in placebo-controlled trials in IBS patients. Pinaverium bromide is also an L-type calcium channel blocker that acts locally in the GI tract. Pinaverium improves motility disorders and consequently reduces stool problems in IBS patients. Phloroglucinol and trimethylphloroglucinol are non-specific antispasmodics that reduced pain in IBS patients in a placebo-controlled trial. Antispasmodics have excellent safety profiles. T-type calcium channel blockers can abolish visceral hypersensitivity in animal models, which makes them potential candidates for the development of novel therapeutic agents in the treatment of IBS. 相似文献
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Lijoy K. Mathew Nicolas Skuli Vera Mucaj Samuel S. Lee Pascal O. Zinn Pratheesh Sathyan Hongxia Z. Imtiyaz Zhongfa Zhang Ramana V. Davuluri Shilpa Rao Sriram Venneti Priti Lal Justin D. Lathia Jeremy N. Rich Brian Keith Andy J. Minn M. Celeste Simon 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(1):291-296
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Laurie J. Rich Eftekhar Rajab Bolookat Mukund Seshadri 《Journal of oral biosciences / JAOB, Japanese Association for Oral Biology》2019,61(4):236-241
The purpose of this study was to apply photoacoustic imaging (PAI), a relatively new imaging method, to non-invasively map neurovascular dynamics in salivary glands. Dynamic PAI with co-registered ultrasound (US) was performed in mice to monitor salivary gland hemodynamics in response to exogenous muscarinic receptor stimulation (pilocarpine) and blockade (atropine). Pilocarpine increased salivary gland oxygen saturation (%sO2) within minutes after administration, which was abrogated by atropine. A significant correlation was observed between change in %sO2 measured by PAI and saliva secretion. PAI is a novel imaging method that can be used for functional assessment of neurovascular dynamics in salivary glands. 相似文献