The main cause of diabetes is:() A: Insufficiencies of insulin secretion by B cells B: Insufficiencies of insulin secretion by A cells C: Insufficiencies of insulin secretion by D cells D: Insufficiencies of somatostatin secretion by B cells E: Insufficiencies of somatostatin secretion by D cells

Which of the following description about islet hormones is correct? A: Pancreatic alpha cells produce glucagon B: Pancreatic beta cells produce insulin with low glucose C: Somatostatin produced by pancreatic delta cells enhances insulin secretion D: Somatostatin produced by pancreatic delta cells enhances glucagon secretion E: Insulin can pass through the plasma membrane

Which of the following are incorrectly paired? ()<br/>A. A: cell: glucagon <br/> B: cell: insulin <br/> C: cell: somatostatin <br/> D: cell: gastrin <br/> E: cell: secretin

在丘脑下部存在的生长激素抑制剂( somatostatin)是一个14肽。它的序列已经通过2,4-二硝基氟苯反应和酶的水解实验测出。试从下列信息中,推出该肽的一级结构。(1)通过2,4-二硝基氟苯反应,知N-端为Ala;(2)选择性的部分水解给出下列肽片段:Phe-Trp 、 Thr-Ser-Cys , Lys-Thr-Phe 、Thr-Phe-Thr-Ser-Cys 、Asn-Phe-Phe-Trp-Lys 和 Ala-Gly-Cys-Lys-Asn-Phe[br][/br](3)该肽有一个二硫键

在丘脑下部存在的生长激素抑制剂(somatostatin) 是一个 14 肽。它的序列 已经通过 2,4- 二硝基氟苯反应和酶的水解实验测出。试从下列信息中,推出该肽的一级 结构。(1) 与 2,4- 二硝基氟苯反应,知 [tex=1.643x1.143]iNWXbFIqHG0UBpXmE2nQ/A==[/tex] 端为[tex=1.857x1.214]1hdwWzQdx4upmhzAcDCT6w==[/tex](2) 选择性的部分水解给出下列然片段序列： Phe-Trp、Thr-Ser-Cys、Lys-Thr-Phe, Thr-Phe-Thr-Ser-Cys、Asn-Phe-Phe-Trp-Lys 和 Ala-GlyCys-Lys-Asn-Phe(3) 该肽有 1 个二硫键。