The short version of 合成七肽 fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-02-20. Anything still debated is marked as such rather than presented as settled.
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
| Property | Value | Notes |
|---|---|---|
| 结构类别 | 线性合成七肽 | 无环化结构，不含二硫键 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | N 端为甲硫氨酸 |
| 分子量 | 约 814 Da | 游离碱形式的计算值 |
| 外观 | 白色至类白色粉末 | 具吸湿性 |
| 溶解性 | 易溶于水 | 亦可溶于甲醇等极性溶剂 |
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Semax is normally supplied as a lyophilized powder, and that form is the most stable. Suppliers commonly recommend storage at -20 °C in a desiccated container protected from light, with short-term handling at room temperature limited to weighing and transfer. Powder that has absorbed moisture degrades faster, so vials should be warmed to ambient temperature before opening to prevent condensation on the contents. Hygroscopic behavior is typical of short hydrophilic peptides, and humidity control matters more than temperature alone for long-term retention.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
=== The Commander === "The Commander" (Jack Farthing) is ostensibly an old friend of Henry's who shows up at his 40th birthday while an intoxicated Henry makes a scene before dinner guests. The Commander takes Henry to a pub where Henry spots his housekeeper Molly and her friend George; after George makes insulting comments about Yasmin, Henry viciously beats him at the Commander's provocation. The Commander is revealed to be Henry's hallucination of his late father, whose suicide on his own 40th birthday was witnessed by Henry as a child. Henry himself nearly attempts suicide the following morning in his father's vintage Jaguar E-Type via carbon monoxide poisoning, but relents at the last moment.
=== Size === Bottles tend to come in standard sizes, often 4 US fluid ounces (120 ml) and 8 US fluid ounces (240 ml). Smaller bottles may be lighter and easier to hold and are often used with younger, smaller infants. There are concerns that larger bottles may lead to over-feeding, since parents are likely to encourage a baby to "finish" a bottle during a feeding. The height-to-width ratio of bottles is high (relative to adult cups) because it is needed to ensure the contents flood the teat when used at normal angles; otherwise the baby will drink air. However, if the bottle is too tall, it easily tips. There are asymmetric bottles that ensure the contents flood the teat if the bottle is held at a certain direction.
== Areas == In-space manufacturing (ISM) can be categorized into three different areas according to the end use of manufactured products. In-space manufacturing for space (space-for-space) involves activities focused on in-orbit construction intended for use in space. ISM for Earth (space-for-Earth) is the production of new materials and products that exhibit enhanced properties when manufactured in microgravity, subsequently transported back to Earth. Lastly, ISM for surface extends to surface operations on celestial bodies such as the Moon, Mars, and asteroids.
Sources: en.wikipedia.org
=== Period 3: final narrative evolution === The final stage at Kizil is Period 3 of the Second Indo-Iranian Style. Towards the end of its florescence, Kizil saw the emergence of the domed central pillar cave, a type of "central pillar" structure, with niche and circumambulating corridor, but with a very uncharacteristic near-cubic main cella crowned by a magnificent cupola decorated with divinities. The style of painting is very refined, and can also be seen in some other caves in the region such as in Kumtura. The iconography too has evolved, with a cosmological Buddha becoming omnipresent and majestic, often surrounded by myriads of emanations of smaller Buddhas. This exceptional and very refined type of cave is exemplified by Cave 123, the "Cave with the Ring-Bearing Doves". It represents a final narrative evolution, in which the figures of the cosmological Buddha predominate, while secondary figures and stories take an ever-smaller role.
FO is a water insoluble protein with eight subunits and a transmembrane ring. The ring has a tetrameric shape with a helix-loop-helix protein that goes through conformational changes when protonated and deprotonated, pushing neighboring subunits to rotate, causing the spinning of FO which then also affects conformation of F1, resulting in switching of states of alpha and beta subunits. The FO region of ATP synthase is a proton pore that is embedded in the mitochondrial membrane. It consists of three main subunits, a, b, and c. Six c subunits make up the rotor ring, and subunit b makes up a stalk connecting to F1 OSCP that prevents the αβ hexamer from rotating. Subunit a connects b to the c ring. Humans have six additional subunits, d, e, f, g, F6, and 8 (or A6L). This part of the enzyme is located in the mitochondrial inner membrane and couples proton translocation to the rotation that causes ATP synthesis in the F1 region. In eukaryotes, mitochondrial FO forms membrane-bending dimers. These dimers self-arrange into long rows at the end of the cristae, possibly the first step of cristae formation. An atomic model for the dimeric yeast FO region was determined by cryo-EM at an overall resolution of 3.6 Å.
The U.S. Army has commissioned ongoing research into potential risks of depleted uranium and other projectile weapon materials like tungsten, which the U.S. Navy has used in place of DU since 1993. Studies by the U.S. Armed Forces Radiobiology Research Institute conclude that moderate exposures to either depleted uranium or uranium present a significant toxicological threat. In 2003, Professor Brian Spratt FRS, chairman of the Royal Society's working group on depleted uranium, said: "The question of who carries out the initial monitoring and clean-up is a political rather than scientific question," and "the coalition needs to acknowledge that depleted uranium is a potential hazard and make in-roads into tackling it by being open about where and how much depleted uranium has been deployed." A 2008 review of all relevant articles appearing in the peer-reviewed journals on MEDLINE through to the end of 2007, including multiple cohort studies of veterans, found no consistent evidence of excess risks of neoplasms that could have some link to DU, and that "[t]he overall incidence of cancers is not increased in the cohort studies of Gulf war and Balkans veterans". One particular subgroup of veterans that may be at higher risk comprises those who have internally retained fragments of DU from shrapnel wounds.
Sources: en.wikipedia.org
不存在。它是依据 ACTH 的一段序列人工设计的分子，天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号，而非天然物质名。
Semax 对应 ACTH 第 4 至第 10 位的片段，并在两端做了替换与延长，使其不再具备促肾上腺皮质激素的典型内分泌活性。这一改动同时改变了它在体内的稳定性与分布特征。
俄罗斯将其列为处方药物，需要医生开具处方。多数其他国家把它当作研究化合物，不能作为药品销售或宣称疗效。具体合法性取决于当地法规。
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。