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柏安診所-提供您長期穩定及先進的醫療照顧
Posted On 4 4 月, 2021 / By / Posted in Harper's Biochemistry (2018)

04. Proteins: Determination of Primary Structure

BIOMEDICAL IMPORTANCE PROTEINS & PEPTIDES MUST BE PURIFIED PRIOR TO ANALYSIS Column Chromatography 藉由column中beads的物理化學性質,將通過的溶液篩出想要的東西 HPLC—High-Pressure Liquid Chromatography 第一代column chromatography的beads很大顆(0.1 mm),flow的效果較差。而總表面積小,限制了添加charged or ligand-like groups 進化的column的beads較細,但阻力變大,因此需要高壓。高壓會把原本由多醣體製成的beads壓碎,後來有silicon beads才克服 Size-Exclusion Chromatography 根據蛋白質的Stokes radii來做篩選 Stokes radii為蛋白質的effective volume

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Posted On 2 4 月, 2021 / By / Posted in Harper's Biochemistry (2018)

02. Water & pH

BIOMEDICAL IMPORTANCE 水為極佳的nucleophile WATER IS AN IDEAL BIOLOGIC SOLVENT Water Molecules Form Dipoles 水分子形狀為四面體 (tetrahedron),兩角為氫、兩角為sp3-hybridized orbitals(混成軌域) 一個軌域可容納兩個電子 氧原子有8個電子,第1層2個,第2層6個 (1s22s22p4) 1個2s及3個2p混合成4個等價呈四面體形狀的sp3混成軌域 碳原子與其它原子以單鍵連接時,碳原子均採用sp3混成形式 Ammonia也是tetrahedron 水分子的氧原子的強大電荷,會把氫原子的電子吸向它,讓氫呈局部正電,而氧的游離成對電子呈局部負電。這樣的局部帶電分子,稱為dipole。 水分子有強的dipole、高的dielectric constant(介電常數),因此可大幅降低charged or polar species之間的吸引力 Water Molecules Form Hydrogen

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Posted On 26 3 月, 2021 / By / Posted in Harper's Biochemistry (2018)

01. Biochemistry & Medicine

BIOMEDICAL IMPORTANCE DISCOVERY THAT A CELL-FREE EXTRACT OF YEAST CAN FERMENT SUGAR BIOCHEMISTRY & MEDICINE HAVE PROVIDED MUTUAL ADVANCES BIOCHEMICAL PROCESSES UNDERLIE HUMAN HEALTH Biochemical Research Impacts Nutrition & Preventive Medicine Most

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Posted On 24 3 月, 2021 / By / Posted in Harper's Biochemistry (2018)

03. Amino Acids & Peptides

BIOMEDICAL IMPORTANCE L–𝛼-Amino acids 腎臟每天超過濾出50克的游離胺基酸,但大部份都回收 PROPERTIES OF AMINO ACIDS The Genetic Code Specifies 20 L-𝛼-Amino Acids 大自然有超過300種胺基酸,絕大多數蛋白質由20種胺基酸組成 Selenocysteine, the 21st Protein L-𝛼-Amino Acid 人類有兩打的selenoproteins,包含iodothyronine deiodinases(把T4轉成T3) UGA為stop codon,但若伴隨著selenocysteine insertion element (stem-loop structure),則此UAG會被tRNASec辨視,進而轉譯selenocysteine上去 Serine的氧變硫就是cysteine、硫變硒就是selenocysteine

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Posted On 21 3 月, 2021 / By / Posted in Harper's Biochemistry (2018)

14. Overview of Metabolism & the Provision of Metabolic Fuels

BIOMEDICAL IMPORTANCE Metabolic pathwats有三種:1. Anabolic 2. Catabolic 3. Amphibolic Anabolic為endothermic(吸熱) Catabolic為exothermic(放熱) Amphibolic為代謝的交叉路口,做為上兩者的連通管道,比如citric acid cycle 人類的日常能量來源:碳水10-15%、脂肪(主要為triacylglycerol)30-40%、蛋白質10-15% 空腹期間的能量來自:肝及肌肉中的肝醣、脂肪中的TG、labile protein stores 飽食後,身體多數組織會利用葡萄糖;在空腹期間,血糖要留給中樞神經及紅血球使用,其它組織可利用替代燃料 肌肉及肝臟可氧化脂肪酸 肝臟從脂肪酸合成酮體,供給肌肉及其它組織使用 當肝醣耗盡,蛋白質turnover裡的胺基酸會被拿來做糖質新生 上述機轉,主要由胰島素及升糖素來調控 PATHWAYS THAT PROCESS THE MAJOR PRODUCTS OF DIGESTION 所有吸收的養份最後都會被代謝成acety

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