mechanism Medicine & Health

17 个科学问题 · 医学健康 Medicine & Health

本页目录

ACE 抑制剂和 ARB 类药物降压机制有何不同?

How do ACE inhibitors and ARBs lower blood pressure differently?

ACE 抑制剂阻断把血管紧张素 I 转为强缩血管物质血管紧张素 II 的酶;ARB 则直接阻断血管紧张素 II 与受体结合。二者都舒张血管、减轻心脏负担,但作用环节不同。
ACE inhibitors block the enzyme converting angiotensin I to the vessel-constricting angiotensin II; ARBs block angiotensin II from binding its receptor. Both dilate vessels and ease the heart's load, but at different steps.
难度 专业 · 适合 小学高段(9-12) CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#ACE抑制剂 #降压

为什么DNA甲基化能够在不改变序列的情况下沉默基因?

Why can DNA methylation silence genes without changing the sequence?

DNA甲基化是在CpG位点的胞嘧啶上添加甲基的化学修饰,会阻碍转录因子结合并招募抑制性蛋白,使该基因较难被读出,属于“表观遗传”调控。这种开关可由年龄、营养和环境影响,并且部分可在细胞分裂中保留。它解释了同卵双胞胎随年龄渐行渐远、以及某些肿瘤因抑癌基因被异常甲基化而失活。
DNA methylation adds a methyl group to cytosines at CpG sites, blocking transcription-factor binding and recruiting repressive proteins so the gene is read less—an epigenetic switch. It responds to age, diet and environment and partly persists through cell division. It explains why identical twins drift apart with age and how some tumours silence tumour-suppressor genes by abnormal methylation.
难度 专业 · 适合 高中(15-18) CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source

Allis 与 Jenuwein《表观遗传学》(Cold Spring Harbor);《自然·遗传学评论》(2020)

Allis & Jenuwein, Epigenetics (Cold Spring Harbor Perspectives); Nature Reviews Genetics (2020)

#DNA甲基化 #表观遗传 #CpG #基因沉默

为什么ACE2受体是新冠病毒进入细胞的关键“大门”?

Why is the ACE2 receptor the key "door" for SARS-CoV-2 to enter cells?

新冠病毒表面的刺突蛋白(S蛋白)会特异地结合细胞表面的ACE2受体,再经TMPRSS2等蛋白酶切开,使病毒包膜与细胞膜融合、释放遗传物质。ACE2在肺、心、肠、肾表达丰富,解释了这些器官易受累。2020年《细胞》杂志Hoffmann等研究明确了这一进入机制,也成为疫苗和抗体药物的靶点。
The viral spike protein binds the cell-surface ACE2 receptor and is then cleaved by proteases such as TMPRSS2, fusing envelope and membrane to release the genome. ACE2 is rich in lung, heart, gut and kidney, explaining why those organs suffer. Hoffmann and colleagues' 2020 Cell study pinned down this entry route, now a target for vaccines and antibodies.
难度 专业 · 适合 高中(15-18) CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source

《细胞》(Cell) Hoffmann 等(2020, doi:10.1016/j.cell.2020.02.052);《柳叶刀》

Cell, Hoffmann et al. (2020, doi:10.1016/j.cell.2020.02.052); Lancet

#ACE2 #刺突蛋白 #病毒进入 #TMPRSS2

自噬(autophagy)是怎样“清理”细胞的?

How does autophagy “clean up” cells?

自噬是细胞用膜把受损蛋白和老旧细胞器包裹成“自噬体”并送到溶酶体降解回收的过程,像内部的保洁系统;它参与抗衰老、抗感染和代谢调控。
Autophagy wraps damaged proteins and old organelles in membranes (autophagosomes) and sends them to lysosomes for breakdown and recycling—an internal cleanup system involved in aging, infection defense, and metabolism.
难度 专业 · 适合 小学高段(9-12) CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#自噬 #细胞清理

淀粉样蛋白在阿尔茨海默病中扮演什么角色?

What role does amyloid play in Alzheimer's disease?

阿尔茨海默病大脑中 β-淀粉样蛋白异常聚集形成斑块,可能触发 tau 蛋白缠结和神经元死亡;但“淀粉样蛋白假说”仍在被修正,淀粉样变只是复杂拼图的一块。
In Alzheimer's, abnormal β-amyloid clumps into plaques that may trigger tau tangles and neuronal death; but the “amyloid hypothesis” is being refined, and amyloid is just one piece of a complex puzzle.
难度 专业 · 适合 小学高段(9-12) CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#淀粉样蛋白 #阿尔茨海默

什么是细胞凋亡?它和“细胞坏死”有何不同?

What is apoptosis, and how does it differ from necrosis?

凋亡是细胞有序、自我启动的“程序性死亡”,不会引发炎症,用于清除多余或受损细胞;坏死则是意外损伤导致的混乱死亡,常伴随炎症。
Apoptosis is orderly, programmed cell death that avoids inflammation, clearing unneeded or damaged cells; necrosis is messy death from injury, often triggering inflammation.
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

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#细胞凋亡 #细胞死亡

为什么线粒体拥有自己的环状DNA,而且几乎只来自母亲?

Why does the mitochondrion have its own circular DNA, and why does it come almost only from the mother?

线粒体源自远古被真核细胞吞入的细菌(内共生学说),保留了独立的环状基因组,编码部分呼吸链蛋白。受精时精子线粒体大多在卵子内被泛素标记并降解,因此子代线粒体DNA基本遗传自母亲,可用于追踪母系谱系。这也使某些线粒体病呈母系遗传特征。
Mitochondria descend from bacteria engulfed long ago by eukaryotic cells (endosymbiosis) and kept a circular genome coding some respiratory-chain proteins. At fertilisation most sperm mitochondria are tagged and destroyed inside the egg, so offspring mtDNA is essentially maternal, useful for tracing maternal lineages. This gives some mitochondrial diseases a maternal inheritance pattern.
难度 进阶 · 适合 高中(15-18) CC BY 4.0 · 已核验 · Verified 2026-10-03
来源 · Source

翟中和《细胞生物学》;《自然·评论》线粒体DNA

Zhai Zhonghe "Cell Biology"; Nature Reviews on mitochondrial DNA

#线粒体DNA #内共生 #母系遗传 #环状基因组

免疫检查点抑制剂为什么能“松开”抗癌刹车?

Why can checkpoint inhibitors “release” the anti-cancer brake?

癌细胞常借“检查点”蛋白(如 PD-1/PD-L1)让免疫系统收手;检查点抑制剂阻断这些信号,恢复 T 细胞对肿瘤的攻击,是癌症免疫治疗的重要突破。
Cancers often exploit “checkpoint” proteins (e.g., PD-1/PD-L1) to silence immunity; checkpoint inhibitors block these signals, restoring T-cell attack on tumors—a major immunotherapy advance.
难度 进阶 · 适合 小学高段(9-12) CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#检查点抑制剂 #免疫疗法

为什么T细胞需要“双信号”才能被真正激活?

Why does a T cell need "two signals" to be truly activated?

第一信号由T细胞受体识别抗原呈递细胞上的抗原肽-MHC复合物提供,仅此还不够,否则易致耐受;第二信号来自抗原呈递细胞表面的共刺激分子(如B7与T细胞CD28结合)。两信号齐备,T细胞才增殖分化为效应与记忆细胞;只有第一信号而无第二信号,反而会让T细胞失能或凋亡,这是避免自身免疫的关键安全阀。
Signal one comes from the T-cell receptor seeing antigen peptide on MHC; alone it risks tolerance. Signal two is costimulation—say B7 on the presenting cell binding CD28—delivered only when danger is present. With both, the T cell proliferates into effector and memory cells; signal one without two instead anergises or kills the cell, a safety valve against autoimmunity.
难度 进阶 · 适合 高中(15-18) 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。

曹雪涛《免疫学》第7版;《自然·免疫学》

Cao Xuetao "Immunology" 7th ed.; Nature Immunology

#T细胞 #双信号 #共刺激 #抗原呈递

β受体阻滞剂为什么能治高血压和心悸?

Why do beta-blockers help hypertension and palpitations?

这类药物阻断肾上腺素对 β 受体的作用,减慢心率、减弱心肌收缩,从而降低血压和减轻心慌;常用于高血压、心绞痛和某些心律失常。是否适用需医生判断。
Beta-blockers block adrenaline's action at beta receptors, slowing heart rate and weakening heart contractions to lower blood pressure and ease palpitations; used in hypertension, angina, and some arrhythmias. A doctor should determine suitability.
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

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#β受体阻滞剂 #心血管

什么是朊病毒(prion)?

What is a prion?

朊病毒是错误折叠的蛋白质,能把正常同类蛋白“带歪”也变成错误折叠,从而自我复制并引发致死性神经退行疾病,如疯牛病;它不含核酸却可传染。
Prions are misfolded proteins that force normal counterparts to misfold too, self-propagating and causing fatal neurodegenerative diseases like mad cow disease; they contain no nucleic acid yet are transmissible.
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

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#朊病毒 #蛋白折叠

什么是内皮功能障碍?

What is endothelial dysfunction?

血管内皮是衬在血管内壁的单层细胞,负责舒张与收缩的平衡;当它受损(如吸烟、高血糖所致),血管易收缩、易形成血栓,是动脉硬化的早期步骤。
The vascular endothelium is the single cell layer lining vessels, balancing dilation and contraction; when damaged (e.g., by smoking or high glucose), vessels constrict and clot more easily—an early step in atherosclerosis.
难度 进阶 · 适合 初中(12-15) CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source

葛均兵 主编,《内科学》第9版,人民卫生出版社,2018(动脉粥样硬化章节涉及内皮功能障碍) ; 另见: Deanfield JE, Halperin E, Ramaswami V. Endothelial dysfunction: a marker of early vascular damage and future cardiovascular disease. American Journal of Cardiology, 1999, 83(6):805-810

Deanfield JE, Halperin E, Ramaswami V. Endothelial dysfunction: a marker of early vascular damage and future cardiovascular disease. American Journal of Cardiology, 1999, 83(6):805-810 ; see also: 葛均兵 主编,《内科学》第9版,人民卫生出版社,2018(动脉粥样硬化章节涉及内皮功能障碍)

#内皮 #心血管

什么是炎症小体(inflammasome)?

What is the inflammasome?

炎症小体是细胞内的一种蛋白复合体,感知到感染或损伤信号后激活,释放促炎因子招集免疫细胞;过度激活与痛风、动脉粥样硬化等有关。
The inflammasome is an intracellular protein complex that, upon sensing infection or damage, activates to release inflammatory signals that summon immune cells; its overactivation links to gout and atherosclerosis.
难度 进阶 · 适合 小学高段(9-12) CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#炎症小体 #免疫

什么是氧化应激?

What is oxidative stress?

当体内活性氧等自由基产生过多、而抗氧化防御不足时,就会氧化损伤 DNA、蛋白和脂肪,长期积累与衰老和多种慢性病相关。
When reactive oxygen species outpace antioxidant defenses, they damage DNA, proteins, and fats—oxidative stress—which accumulates with aging and links to many chronic diseases.
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

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#氧化应激 #自由基

缺氧(hypoxia)如何在细胞层面被感知?

How is low oxygen (hypoxia) sensed at the cellular level?

细胞通过 HIF(缺氧诱导因子)感知低氧:缺氧时 HIF 稳定并进入细胞核,开启促红细胞生成素等基因以帮助适应;这一机制曾获诺贝尔奖。
Cells sense low oxygen via HIF (hypoxia-inducible factor): stabilized under hypoxia, HIF enters the nucleus and switches on genes like erythropoietin to adapt—a mechanism honored by a Nobel Prize.
难度 入门 · 适合 大众 CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#缺氧 #HIF

他汀类药物是如何降低胆固醇的?

How do statins lower cholesterol?

他汀抑制肝脏合成胆固醇的关键酶 HMG-CoA 还原酶,促使肝细胞从血液中摄取更多低密度脂蛋白(LDL),从而降 LDL 水平;它也有轻度抗炎作用。具体用药须遵医嘱。
Statins inhibit HMG-CoA reductase, the liver enzyme key to cholesterol synthesis, prompting liver cells to pull more LDL from the blood, lowering LDL; they also have mild anti-inflammatory effects. Medication use must follow a doctor's guidance.
难度 入门 · 适合 大众 CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#他汀 #胆固醇

单克隆抗体药物是怎样“精准”作用的?

How do monoclonal antibody drugs act “precisely”?

单克隆抗体是实验室制造的、只认一种特定靶标(如某炎症因子或癌抗原)的抗体,能像钥匙配锁一样中和或标记目标,广泛用于自身免疫病和癌症。
Monoclonal antibodies are lab-made antibodies targeting one specific molecule (e.g., an inflammatory cytokine or cancer antigen), neutralizing or flagging it like a key in a lock, widely used in autoimmune disease and cancer.
难度 入门 · 适合 大众 CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source

王庭槐 主编,《生理学》第9版,人民卫生出版社,2018

Wang Tinghuai ed., Physiology, 9th ed., People's Medical Publishing House, 2018

#单抗 #靶向治疗