什么是休克？
What is shock?
休克是全身组织灌注严重不足、细胞缺氧的危急状态，可由大出血、严重感染或过敏引起。表现为血压骤降、脉搏细速、意识模糊，需立即抢救。
Shock is a critical state of severely inadequate blood flow to tissues, starving cells of oxygen, caused by massive bleeding, severe infection or allergy. It shows as a sudden blood-pressure drop, fast weak pulse and confusion, and needs immediate treatment.
难度 专业 · 适合 大众
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。
Vincent JL 等《循环休克临床综述》. Critical Care, 2008
Vincent JL, et al. Clinical review: circulatory shock. Crit Care. 2008.
#休克 #循环 #急救
什么是过敏反应？
What is an allergic reaction?
过敏是免疫系统把花粉、食物等无害物质误判为威胁，释放组胺等引发红肿、瘙痒或流涕。严重时会发展为危及生命的过敏性休克。
An allergy is when the immune system mistakes harmless things like pollen or food for threats and releases histamine, causing redness, itching or a runny nose. Severe cases can become life-threatening anaphylactic shock.
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：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。
Johansson SG 等《变应性疾病的修订命名》. Allergy, 2001
Johansson SG, et al. A revised nomenclature for allergy. Allergy. 2001.
#过敏 #组胺 #免疫
为什么会出现耳鸣？
Why does tinnitus (ringing in the ears) occur?
耳鸣是耳内或头部听到实际不存在的声音，常因噪声损伤、衰老或耳蜗功能异常引起。它也可能是某些药物或心血管问题的信号。
Tinnitus is hearing a sound with no external source, often from noise damage, aging or inner-ear dysfunction. It can also signal certain medications or cardiovascular issues.
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：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。
Eggermont JJ, Roberts LE《耳鸣的神经科学》. Trends in Neurosciences, 2004
Eggermont JJ, Roberts LE. The neuroscience of tinnitus. Trends Neurosci. 2004.
#耳鸣 #听力 #耳蜗
为什么“卷舌”能力并非由单一显基因决定，而是受多因素影响？
Why is tongue-rolling not decided by a single dominant gene but by multiple factors?
教科书曾把能否卷舌说成单基因显隐性遗传的经典例子，但双胞胎和家系研究并不支持简单孟德尔模式，同卵双胞胎也出现不一致。现代行为遗传学研究提示它受多条基因与口腔肌肉发育、训练共同影响，更像连续性状。因此卷舌不能用来推断亲属间的遗传关系。
Textbooks once taught tongue-rolling as a clean Mendelian dominant trait, but twin and family studies do not support simple inheritance, and even identical twins can differ. Modern behavioural genetics suggests many genes plus oral-muscle development and practice shape it, more like a continuous trait. So rolling cannot prove family relationships.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
双生子研究(1952; doi:10.1093/oxfordjournals.jhered.a106251)；行为遗传学研究
Twin studies (1952; doi:10.1093/oxfordjournals.jhered.a106251); behavioural genetics research
独立核验依据 · Independent verification: 核验依据 1 CROSSREF 标识 10.1093/oxfordjournals.jhered.a106251：IDENTI
#卷舌 #遗传 #行为遗传学 #孟德尔
人体最强壮的肌肉是哪一块？
What is the strongest muscle in the human body?
若按持续耐力看，心肌一生不停跳动最为持久；若按相对力量看，下颌的咬肌可产生很大咬合力。不同标准下“最强”含义不同。
By endurance, the heart muscle is strongest, beating for a lifetime; by relative force, the jaw's masseter can generate a large bite force. 'Strongest' depends on the standard used.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
《格氏解剖学》（Gray's Anatomy, Standring 主编）
Gray's Anatomy (Standring, ed.).
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-7020-5230-9 (Elsevier)
#肌肉 #咬肌 #心肌
什么是晕厥（昏倒）？
What is fainting (syncope)?
晕厥是脑部短暂供血不足导致的突发意识丧失，常因久站、疼痛或情绪紧张引起。平卧后血流恢复，多数人很快清醒。
Fainting is a brief loss of consciousness from a temporary drop in brain blood flow, often triggered by standing too long, pain or emotional stress. Lying down restores flow and most people recover quickly.
难度 进阶 · 适合 大众
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
#晕厥 #脑供血 #意识
献血会对身体有害吗？
Is donating blood harmful to the body?
健康成年人每次捐献200到400毫升血液是安全的，骨髓会很快补充血细胞。适度献血还可能刺激造血并更新血液，但需符合体重和健康要求。
For healthy adults, donating 200 to 400 mL at a time is safe, and the bone marrow quickly replaces the cells. Moderate donation may even stimulate blood formation, but weight and health criteria must be met.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
《默克家庭医学手册》Merck Manual Home Health Handbook 中译版,人民卫生出版社
The Merck Manual Home Health Handbook, Chinese ed., PMPH
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9787117181631（按标识回读: 默克家庭医学手册）
#献血 #血液 #健康
人头发变白的原因是什么？
Why does hair turn gray?
头发颜色来自毛囊中的黑色素，随年龄增长黑素细胞活性下降，产色减少。遗传、压力和某些疾病也会加速白发出现。
Hair color comes from melanin made in the follicle; with age, melanocyte activity falls and less pigment is produced. Genetics, stress and some illnesses can speed up graying.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
《菲茨帕特里克临床皮肤病学》（Fitzpatrick's Dermatology）
Fitzpatrick's Dermatology in General Medicine.
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL18408881W：Fitzpatrick's dermatol
#白发 #黑色素 #衰老
眼泪里都有什么成分？
What is in tears?
基础泪液含水分、盐分、蛋白质和油脂，用来润滑和保护眼球。情绪性流泪还会带走压力相关的化学物质，因此哭后常感轻松。
Basal tears contain water, salt, proteins and oils that lubricate and protect the eye. Emotional tears also wash away stress-related chemicals, which is why crying can bring relief.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
《格氏解剖学》（Gray's Anatomy, Standring 主编）
Gray's Anatomy (Standring, ed.).
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-7020-5230-9 (Elsevier)
#眼泪 #情绪 #润滑
为什么会出现妊娠纹？
Why do stretch marks appear?
妊娠纹是皮肤在快速撑大时，真皮层胶原和弹性纤维断裂形成的萎缩性条纹。常见于怀孕、青春期生长或体重骤增，初期红紫、日久变白。
Stretch marks form when the dermis is rapidly stretched and its collagen and elastic fibers tear, leaving atrophic streaks. They appear with pregnancy, adolescent growth spurts or rapid weight gain, starting red-purple and fading white over time.
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。
Korgavkar K, Wang F《妊娠纹的局部治疗综述》. British Journal of Dermatology, 2015
Korgavkar K, Wang F. Striae gravidarum: a review of topical management. Br J Dermatol. 2015.
#妊娠纹 #皮肤 #胶原
为什么人会出现“鼻周期”，即两侧鼻孔轮流通气？
Why do people have a "nasal cycle" where each nostril alternates airflow?
鼻腔黏膜下的血管丛会周期性充血，使一侧下鼻甲肿胀、气流减少，约每2–4小时两侧交替一次，由自主神经调控。这种“鼻周期”让鼻腔轮流休息并调节吸气的湿度和温度，对健康无害，多数人毫无察觉。感冒时一侧肿胀更明显，才会让人感觉“总有一边堵”。
Vessel beds under the nasal lining swell cyclically, narrowing one inferior turbinate and its airflow, switching sides every 2–4 hours under autonomic control. This “nasal cycle” lets each side rest and conditions the incoming air, is harmless and goes unnoticed. Only with a cold does one side swell enough to feel “always blocked”.
难度 入门 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
朱大年《生理学》第9版；《生理学杂志》(Journal of Physiology)
Zhu Danian "Physiology" 9th ed.; Journal of Physiology
#鼻周期 #下鼻甲 #自主神经 #鼻腔
皮肤晒后为什么会变黑？
Why does skin get darker after sun exposure?
紫外线刺激皮肤增加黑色素生成，以吸收有害射线保护底层细胞。这种色素沉着就是晒黑，也是身体的一种防御。
Ultraviolet light stimulates the skin to make more melanin, which absorbs harmful rays and protects deeper cells. This pigment buildup is tanning, a defensive response of the body.
难度 入门 · 适合 大众
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。
Lin JY, Fisher DE《黑素细胞生物学与皮肤色素》. Nature, 2007
Lin JY, Fisher DE. Melanocyte biology and skin pigmentation. Nature. 2007.
#晒黑 #黑色素 #紫外线
指纹真的是独一无二的吗？
Are fingerprints truly unique?
每个人的指纹图案由胎儿期基因和子宫环境共同决定，彼此不同。即使同卵双胞胎的指纹也不完全一致，因此被广泛用于身份识别。
Each person's fingerprint pattern is shaped by genes and the womb environment during fetal development and is distinct. Even identical twins have different prints, which is why they are widely used for identification.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
《格氏解剖学》（Gray's Anatomy, Standring 主编）
Gray's Anatomy (Standring, ed.).
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-7020-5230-9 (Elsevier)
#指纹 #身份 #唯一性
为什么天冷时人会出现“冷利尿”，尿量反而变多？
Why does cold exposure cause "cold diuresis" with more urine?
寒冷使皮肤血管收缩以减少散热，回心血量和血压上升，身体通过排钠利尿来把血容量调回正常，于是尿量增多。同时寒冷会轻度抑制抗利尿激素释放，也助长排尿。这是为什么冬天在户外待久常想上厕所，并不代表喝多了水。
Cold makes skin vessels constrict to save heat, raising venous return and blood pressure, so the body sheds sodium and water to bring volume back to normal—more urine. Cold also mildly suppresses antidiuretic hormone, adding to the effect. That is why you want to urinate after standing outside in winter, not because you drank more.
难度 入门 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
朱大年《生理学》第9版；《应用生理学杂志》(Journal of Applied Physiology)
Zhu Danian "Physiology" 9th ed.; Journal of Applied Physiology
#冷利尿 #血管收缩 #抗利尿激素 #体温调节
人为什么要眨眼？
Why do we blink?
眨眼用泪液均匀涂抹角膜、清除灰尘并保持眼球湿润。成人每分钟约眨眼10到20次，也能在瞬间保护眼睛免受异物撞击。
Blinking spreads tears evenly over the cornea, clears dust and keeps the eye moist. Adults blink about 10 to 20 times a minute and the reflex also protects the eye from sudden impacts.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
Guyton 与 Hall，《医学生理学教科书》（第13版，Elsevier，2016）
Guyton & Hall, Textbook of Medical Physiology (13th ed., Elsevier, 2016)
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-323-59712-8 · 核验依据 2 ISBN 978-1-4557-4377-3 (3rd ed., Elsevier) · 核验依据 3 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#眨眼 #泪液 #眼睛
皮肤被撞后为什么会出现淤青？
Why does a bruise appear after a bump?
撞击使皮下小血管破裂，血液漏入组织形成紫红色淤斑。随后血红蛋白被逐步分解，颜色由青紫转为黄绿后消退。
A bump breaks tiny blood vessels under the skin, leaking blood into the tissue as a purplish mark. As the hemoglobin breaks down, the color shifts from blue-purple to yellow-green and then fades.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 2 条独立证据
来源 · Source
《默克家庭医学手册》(Merck Manual Home Health Handbook) 中译版,人民卫生出版社（瘀伤/软组织损伤条目）
The Merck Manual Home Health Handbook, Chinese ed., People's Medical Publishing House (bruises/soft-tissue injury entry)
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9787117181631（按标识回读: 默克家庭医学手册）
#淤青 #血管 #血红蛋白
人为什么会打嗝？
Why do people hiccup?
打嗝是膈肌不自主痉挛使声门突然关闭，发出“嗝”声。多由进食过快、胃胀或受凉刺激膈神经引起，通常短暂自行停止。
A hiccup is an involuntary spasm of the diaphragm that suddenly closes the vocal cords, making the 'hic' sound. It is often triggered by eating too fast, a full stomach or cold that irritates the phrenic nerve, and usually stops on its own.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
Guyton & Hall《医学生理学》（呼吸反射章节）
Guyton & Hall. Textbook of Medical Physiology (respiratory reflex chapter).
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-323-59712-8 · 核验依据 2 ISBN 978-1-4557-4377-3 (3rd ed., Elsevier) · 核验依据 3 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#打嗝 #膈肌 #痉挛
为什么冷的时候会起鸡皮疙瘩？
Why do we get goosebumps when cold?
起鸡皮疙瘩是立毛肌收缩使毛发竖起，在祖先身上能困住空气保暖。人类毛发变细后作用减弱，但这一反射仍保留下来。
Goosebumps come from tiny muscles pulling hairs upright, which in our furry ancestors trapped warm air. Human body hair is now fine, so the effect is weak, but the reflex remains.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
Guyton 与 Hall，《医学生理学教科书》（第13版，Elsevier，2016）
Guyton & Hall, Textbook of Medical Physiology (13th ed., Elsevier, 2016)
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-323-59712-8 · 核验依据 2 ISBN 978-1-4557-4377-3 (3rd ed., Elsevier) · 核验依据 3 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#鸡皮疙瘩 #立毛肌 #体温
成年人身体里有多少块骨头？
How many bones are in the adult human body?
成年人通常有206块骨头，婴儿则更多，因为部分骨骼会随生长融合。骨骼支撑身体、保护内脏并储存钙等矿物质。
Adults typically have 206 bones; babies have more because some fuse during growth. Bones support the body, protect organs and store minerals such as calcium.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
《格氏解剖学》（Gray's Anatomy, Standring 主编）
Gray's Anatomy (Standring, ed.).
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-0-7020-5230-9 (Elsevier)
#骨骼 #骨头 #支撑