Integumentary System 皮膚系統 表皮 真皮 皮下層 特 點 - Body’s covering (2m2, ~5kg, 16(8)% of B.W.) - Includes: skin, hairs, nails and glands - Skin (largest organ): cutaneous membrane
Skin (薄；hair) + 附屬 皮膚的功能 (佔1/5) 皮膚的功能 1. Protection--keratin, melanin, sweat(酸), sebum, hair, nail 2. Temperature regulation--sweat, blood 3. Storage--fat, blood 4. Sensory reception--tactile, thermal, pain 5. Excretion and absorption--small amounts 6. Vitamin D synthesis--助 Ca,P吸收 / 抗菌肽cathelicidin產生
最內St. germinativum (增生層) Epidermis 表皮 --Dermis 最外St. corneum (角質層) 1. Dead cells: 多層, 富keratin (防水) 2. 表面有菌落 3. Blisters, 受壓生callus, print (會變) 最內St. germinativum (增生層) 1. Basal part, 雜有 Merkel cells 2. 能Mitosis (grow) 3. 開始合成keratin, 生vit. D / defensin 最厚epidermis: 手掌, 足底(sole), 指尖 Thick skin = 5 mm厚, epi. 5種細胞層; 上背最厚(∵dermis) Thin skin: <1 mm, 眼瞼最薄 (epidermis=0.08mm)
厚皮表皮 (Epidermis) 分層 Five Layers (strata) 1. Stratum corneum (角質層) -扁化 dead cells (20~30-layer) -Cells consist mostly of keratin -Cells shed & replaced from below 2. St. lucidum (透明層) -3~5 layers; anuclear; keratin-rich -in thick skin (palm, sole, fingertip) 3. Stratum granulosum (顆粒層) -Makes keratohyalin (嗜鹼性) -Losing cell organelles and nuclei -Present waterproofing lipid 4. Stratum spinosum (棘狀層) -8~10 cell layers -Cells becoming flattened -Provides strength & flexibility 5. Stratum basale (基底層=增生層) -Single row, includes stem cells -Living portion, new cells arise (thick, hairless) Callus (繭), Keratinization, 頭皮屑 基底層表面脫落 (約 4 wk)
表皮的細胞 1. Keratinocytes 角質細胞 2. Melanocytes 黑色素細胞 -90% of epidermal cells -生 keratin (角蛋白), defensin & Vit. D -Waterproofs : lamellar granules, release lipid-rich sealant (密封劑,鍍膜) 2. Melanocytes 黑色素細胞 -Lower portion; 8% of epidermal cells -Produce melanin (黃紅/棕黑; from tyrosine; absorb UV) that gives color to skin & hairs -Transfer pigment to keratinocytes -Number is about the same in all people -Albinos (白子, No melanin) 3. Langerhans cells 蘭氏細胞 -Immune (Antigen-presenting, innate) -Mobile, phagocytic 4. Merkel cells 牟氏細胞 -Sense of touch (Tactile) -Consist of tactile disc and neuron for touch sensation
Skin Color 佝僂症(Rickets) -Vit D3 缺乏 -Ca ? Melanin (量): dark color Carotene: yellow orange -In 角質層及脂肪層 Hemoglobin: pink-red Tattooing 紋身 -foreign pigment deposited in dermis (permanent) -Egypt (2000-4000B.C.) -laser removal (dissolve) -investment: time, money, pain
Finger print 表皮嵴
真皮 The Dermis Irregular fibrous CT: 強度、彈性 Layers: 乳頭層 + 網狀層 (dense CT) 真皮 The Dermis (觸,壓-有被膜) Irregular fibrous CT: 強度、彈性 Layers: 乳頭層 + 網狀層 附屬構造: 毛囊、汗腺、血管、神經 Circulation: 紅潤 vs. 發紺 (cyanosis) (decubitus ulcer褥瘡)
皮下層 Subcutaneous 又稱 Superficial fascia, 由疏鬆結締(蜂窩)組織構成，內含: 1. 脂肪細胞--避免體溫的流失、儲存能量和吸收震動。 2. Mast cells --產生histamine, leukotriene, 發炎因子。 功同 2nd-line of defense, 有利於 WBC、細菌移動。 皮下層上層區的血管多，其他區血管少、且無重要的器官，適合 吸收較慢的皮下注射(e.g., insulin) 。 Intramuscular inj.
1.人生：不可能全都有，要選擇。 順序：健康-家庭-事業 2.健康：身(飲食運動) 心(萬般由心，心安理得) 3.成功：非偶然; 智慧，熱情，毅力
(Accessory Structures of Skin) 皮 膚 的 附 屬 構 造 (Accessory Structures of Skin) 毛髮,毛囊,汗腺 皮脂腺,指/趾甲 毛髮與毛囊 (Hair and Hair Follicles) 毛髮是由最深層的毛囊 (hair follicle) 幹細胞分化形成 毛囊是表皮(epidermis) 下陷而成的構造 毛囊最底端為毛球(bulb) 毛髮的功能 (Functions of Hair) 1. 頭髮保護頭皮、避免紫外線的傷害 2. 鼻孔、外耳道和眼瞼: 避免顆粒或小昆蟲入侵 3. 重要的感覺接受器
毛髮和毛囊 Hair (“goose bumps”) (Dermal) (生hair) -on most skin -手掌/腳掌/唇/甲 除外 Hair -cuticle 角質 -cortex 皮質 -medulla 髓質 ※ iRS eRS (“goose bumps”) ※ (Dermal) (生hair) Follicle = root sheath -internal R.S. -external R.S.
Resting 15% in scalp (2mm/wk) (5%, 最多2ml/天)
Skin-- Glands Holocrine -皮脂腺 apocrine 分布於額、上唇；手掌和腳底 最多(500/cm2) 汗液: 水分> 99%，餘為電解質、 代謝廢物等。(氣味獨特) 調體溫 Holocrine -皮脂腺 apocrine -開口於毛囊,青春期始分泌 -分泌物: 含脂肪,蛋白質(造 成體臭) -分布: 會陰,腋下,乳頭周圍 -特化: 乳腺,耵聹腺 (ceruminous) Sebum(抑菌) 堆積 (炎)Acne粉刺/青春痘 1.Pimples 痘/疹(菌) 2.Pustule 膿皰 3.Blackheads (口大;鼻)
Accessory Structures of Skin -- Nails Dorsal matrix (甲上皮) 甲弧 (plate) 甲下皮 (1mm/wk) (proximal nail bed甲床) 1. Lunula : thick opaque/部分角化matrix ; 血管較模糊 2. Nail body (plate) : 似毛cortex = 密keratin 絲+ 無形keratin, S-rich
皮膚修復的步驟 (Steps Involved in Repairing the Skin) (血, bv, fibroblasts) 皮膚修復的步驟 (Steps Involved in Repairing the Skin) 皮膚受傷復原的四個時期
Common Disorder 1. Skin cancer –carcinoma(basal, sq.), melanoma(melanocyte) 2. Acne (粉刺, 皮脂腺發炎) 3. Sun damage (日光10%為UV-A; 地面UV, A佔95%老化,癌 ) 4. Burns (組織傷, by: UV-B) 5. Impetigo, eczema, warts, fever blister Basal cell carcinoma Normal nevus (mole) Melanoma, 轉移 Malignant melanoma -Asymmetry -Border -Color(雜) -Diameter (>6mm) -Evolution/Elevation
5. Impetigo, eczema, warts, fever blister Common Disorder 1. Skin cancer – carcinoma(basal, sq.),melanoma(melanocyte) 2. Acne (粉刺, 皮脂腺發炎) 3. Sun damage (日光10%為UV-A; 地面UV, A佔95%老化,癌 ) 4. Burns (組織傷, by: UV-B) 5. Impetigo, eczema, warts, fever blister impetigo膿皰-鏈球菌 fever blister泡疹 -virus, 唇邊或潛伏 warts疣-virus Eczema異位皮膚炎 -過敏 Lamellar ichthyosis -層狀魚鱗癬 -穿山甲人 -角質化不良 -脫屑, 禿髮, 眼瞼外翻 -防水? 排汗? -Chr. 14 (2/3/19), 隱性
高腳鴴
Shingles 帶狀皰疹 百痛之王 age,免疫 1.清 水痘 chickenpox 2.膿 4.痂 (2-4wk) 3.血
benzophenone (二苯甲酮): 1. Fun in the Sun 2. Sunscreens: (spf 15~50) benzophenone (二苯甲酮): - absorb UVB--most damage - UVB傷表層; 紅腫熱痛 spf 15: -1/15 UV達皮膚 - 效用: 15x - 遮蔽率=(15-1)/15=93.3% Side effects –刺激,過敏 3. Sunblocks: ZnO2 4. Excessive exposure cause skin cancer
中午,burns,致癌,vit D
Burns Protein denature, 脫水, 感染, septicemia菌血症 By: heat(水火), sun, 凍, 輻射, 電, chemicals(酸鹼) (d) 四級肌,骨 Involve: epidermis No blisters 3-6 day to heal “superficial” ~part of dermis redness, blisters(histamine) edema 3-4 wk to heal, scar forms ~subcutaneous layer most functions lost skin graft require numb in burned region When burned area exceeds 70%, more than half the victims die.
面積的估計 Rule of Nines
2017.1.16. (臘腸菌毒素) <50% in 醫美 (稱Oculinum) “cash-cow” Heart trouble 機轉complex, mystery 2017.1.16.
祝君 健康快樂
Cosmetic Anti-aging Treatment 1. Topical (局部) product 2. Microdermabrasion --tiny crystal 3. Chemical peel --mild acid 4. Laser resurfacing --clear up b.v., blotches斑… 5. Dermal fillers 6. Fat transplantation 7. Botulin toxin (Botox) --paralyze muscle 8. Radio frequency nonsurgical facelift (除皺) --tighten deeper layer 9. Facelift, browlift, or necklift (美容--拉皮)