直接免疫荧光检查如何区分寻常型天疱疮和大疱性类天疱疮?
How does direct immunofluorescence distinguish pemphigus vulgaris from bullous pemphigoid?
寻常型天疱疮的IgG和C3沉积在角质形成细胞表面,呈现特征性的棘细胞间网状荧光,对应针对桥粒芯蛋白的自身抗体。大疱性类天疱疮则表现为IgG和C3沿基底膜带连续线状沉积,靶抗原是位于半桥粒的BP180和BP230。结合盐裂试验可进一步判定分离平面——类天疱疮的荧光留在表皮侧,与天疱疮形成明确对照。
In pemphigus vulgaris, IgG and C3 decorate keratinocyte cell surfaces, producing the hallmark intercellular net-like pattern aimed at desmogleins. Bullous pemphigoid shows continuous linear IgG and C3 deposition along the basement membrane zone, targeting BP180 and BP230 within hemidesmosomes. Salt-split skin testing refines the distinction: pemphigoid fluorescence remains on the epidermal side of the split, cleanly contrasting with the intercellular staining of pemphigus.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Harrison's Principles of Internal Medicine 第20版,McGraw-Hill,2018
J. Loscalzo et al., Harrison's Principles of Internal Medicine, 20th ed., McGraw-Hill, 2018
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY ISBN 标识 9781259644047（按标识回读: Harrison's prin
#直接免疫荧光 #自身免疫性大疱病
雄激素性脱发为什么这么常见，有哪些有效办法？
Why is androgenetic hair loss so common, and what actually works?
在遗传易感的人群中，睾酮经5α-还原酶转化的二氢睾酮会作用于特定部位的毛囊，使其逐代“微小化”，毛发变细变短最终停止生长。男性多表现为发际线后退和头顶稀疏，女性多为发缝变宽、整体密度下降。它与洗头频率、戴帽子无关。目前证据充分的手段是外用米诺地尔和男性口服非那雄胺（需医生处方并了解不良反应），越早干预保留的毛囊越多；女性用药方案不同，应先排查缺铁、甲状腺疾病等原因。
In genetically susceptible people, dihydrotestosterone converted from testosterone by 5-alpha-reductase acts on follicles in specific areas, miniaturizing them cycle after cycle so hairs grow thinner and shorter until they stop. Men typically show a receding hairline and thinning crown, women a widening parting and diffuse loss of density. It has nothing to do with how often you wash your hair or whether you wear hats. The best-evidenced options are topical minoxidil and, for men, oral finasteride on prescription with its side effects understood; earlier treatment preserves more follicles, while women need a different regimen and should first be checked for iron deficiency or thyroid disease.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Harrison's Principles of Internal Medicine 第20版,McGraw-Hill,2018
J. Loscalzo et al., Harrison's Principles of Internal Medicine, 20th ed., McGraw-Hill, 2018
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY ISBN 标识 9781259644047（按标识回读: Harrison's prin
#雄激素性脱发 #二氢睾酮 #毛囊微小化 #米诺地尔
银屑病（牛皮癣）会传染吗？
Is psoriasis contagious?
不会。银屑病是免疫介导的慢性炎症性皮肤病，与IL-23/Th17免疫通路过度活化和遗传易感性有关，表皮细胞增殖过快形成红斑与银白色鳞屑，接触、共用毛巾或游泳都不会传播。它常伴关节炎、代谢综合征、心血管疾病和抑郁，因此被视为系统性疾病。治疗从外用药、光疗到口服药和生物制剂，多数患者可以有效控制，世界卫生组织2014年通过决议呼吁减少对患者的歧视。
No. Psoriasis is a chronic immune-mediated inflammatory skin disease driven by overactivity of the IL-23/Th17 pathway in genetically susceptible people, in which epidermal cells proliferate too fast and form red plaques with silvery scale; it cannot spread by touch, shared towels or swimming pools. It frequently comes with arthritis, metabolic syndrome, cardiovascular disease and depression, so it is regarded as a systemic condition. Treatment ranges from topicals and phototherapy to oral drugs and biologics, giving most patients good control, and a 2014 WHO resolution called for an end to stigma against those affected.
难度 进阶 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：作者 / 书名 / 版次 / 出版社 / 年份齐备，仅缺独立比对证据；已在可信度报告单列披露，不再重复核验。
张迈予 主编,《皮肤性病学》第9版,人民卫生出版社,2018
Bolognia JL, Jorizzo JL, Schaffer RV, eds. Dermatology. 4th ed. Elsevier, 2018
#银屑病 #免疫介导 #不传染 #生物制剂
口服异维A酸治疗重度痤疮期间,医生为什么要求患者定期复查血脂和肝功能?
Why do clinicians order regular lipid panels and liver function tests for patients taking oral isotretinoin for severe acne?
异维A酸可引起血清甘油三酯升高和高密度脂蛋白胆固醇下降,升幅多出现在用药后头两个月内。部分使用者还会出现转氨酶轻度升高,绝大多数为可逆性改变。因此指南建议基线检测后于用药第1—2个月复测,结果稳定者可延长至每季度一次。
Isotretinoin can raise serum triglycerides and lower HDL cholesterol, with most lipid changes emerging within the first two months of therapy. Mild, usually reversible transaminase elevations also occur in a subset of patients. Guidelines therefore recommend baseline testing followed by repeat checks at months 1-2, extending to quarterly monitoring once values are stable.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
中华医学会皮肤性病学分会,《中国痤疮治疗指南(2019修订版)》;Layton AM 等异维A酸安全性综述,Br J Dermatol
Chinese Society of Dermatology, Chinese Guidelines for the Treatment of Acne Vulgaris (2019 revision); Layton AM et al., isotretinoin safety review, Br J Dermatol
#异维A酸 #药物监测
银屑病的Auspitz征是怎样产生的,检查时如何引出?
What produces Auspitz sign in psoriasis, and how is it elicited during examination?
轻刮银屑病皮损表面的鳞屑后出现点状渗血,即为Auspitz征。其机制是角化不全伴棘层肥厚,真皮乳头向上延伸呈杵状,顶端毛细血管迂曲扩张,仅覆以极薄的乳头上表皮,刮去鳞屑后刮破乳头顶部即出血。该体征结合薄膜现象,有助于银屑病与脂溢性皮炎、慢性湿疹的鉴别。
After gently scraping the scales off a psoriatic plaque, pinpoint bleeding appears; this is Auspitz sign. Parakeratosis with acanthosis makes the dermal papillae elongate into clubbed projections whose dilated, tortuous capillaries lie beneath a very thin suprapapillary epidermis, so scraping removes the scale and ruptures the papillary tips. Together with the film phenomenon, the sign helps separate psoriasis from seborrheic dermatitis and chronic eczema.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Harrison's Principles of Internal Medicine 第20版,McGraw-Hill,2018
J. Loscalzo et al., Harrison's Principles of Internal Medicine, 20th ed., McGraw-Hill, 2018
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY ISBN 标识 9781259644047（按标识回读: Harrison's prin
#银屑病 #皮肤体征
晒黑是皮肤受伤了吗?黑色素细胞到底在保护什么?
Is a tan damaged skin — what are melanocytes actually protecting?
晒黑的本质是防御升级的信号。紫外线UVA穿透真皮产生活性氧老化胶原,UVB直接损伤角质形成细胞的DNA;酪氨酸酶被激活后,黑色素细胞加速合成黑色素并打包成黑素体分发给周围的角质细胞,像小伞盖在细胞核上方吸收散射紫外线、减轻DNA的光损伤。肤色加深说明防线已经动用,而此前晒红脱皮则是DNA损伤触发的炎症与凋亡——晒伤一次即累积突变风险。防晒霜SPF标的是对UVB的防护倍数,广谱标签才覆盖UVA;硬防晒(衣物阴影)永远排第一位。
A tan signals defense mobilized. UVA penetrates the dermis generating reactive oxygen that ages collagen; UVB damages keratinocyte DNA directly. Activated tyrosinase drives melanocytes to synthesize melanin packaged into melanosomes distributed to neighboring keratinocytes — little umbrellas over each nucleus scattering UV and shielding DNA from photodamage. Darkening means defenses engaged; earlier redness and peeling are inflammation and apoptosis from DNA damage — every sunburn banks mutations. SPF numbers rate UVB protection, broad-spectrum labels add UVA, and shade plus clothing outrank any lotion.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
D'Orazio, Jarrett, Amaro-Ortiz & Scott,《UV Radiation and the Skin》,International Journal of Molecular Sciences,2013 (DOI: 10.3390/ijms140612222)
D'Orazio, Jarrett, Amaro-Ortiz & Scott, 'UV Radiation and the Skin', International Journal of Molecular Sciences, 2013, DOI: 10.3390/ijms140612222
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.3390/ijms140612222
#紫外线 #黑色素细胞 #光防护