Everything below concerns peptide synthesis. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-04-29. Numbers and descriptions here follow the published literature rather than marketing material.
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
| Property | Value | Notes |
|---|---|---|
| 化学类别 | 合成七肽 | ACTH(4-10) 结构类似物 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | 单字母写作 MEHFPGP |
| 分子量 | 约 813.9 Da | 随确切形式和盐型略有变化 |
| 常见同义词 | ACTH(4-10) 类似物 | 俄语文献称 Семакс |
| 开发来源 | 俄罗斯 | 二十世纪八十年代 |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
=== Tobacco === Polonium-210 in tobacco contributes to many of the cases of lung cancer worldwide. Most of this polonium is derived from lead-210 deposited on tobacco leaves from the atmosphere; the lead-210 is a product of radon-222 gas, much of which appears to originate from the decay of radium-226 from fertilizers applied to the tobacco soils. The presence of polonium in tobacco smoke has been known since the early 1960s. Some of the world's biggest tobacco firms researched ways to remove the substance—to no avail—over a 40-year period. The results were never published.
== Function == In bony fishes, stanniocalcin is the principal hormone that regulate calcium level. Even though other calcium-decreasing hormone, calcitonin, is also present, these fishes require more efficient hormone as calcium rapidly enters into their blood through their gills and intestinal wall. Hence, the target sites of stanniocalsin are gill and intestine, where uptake (absorption) of calcium is directly inhibited. Increase in the serum calcium triggers the release of stanniocalcin. Unlike calcitonin, it also regulates phosphate level. It inhibits excretion of phosphate from the kidney.
=== Byzantine mosaics === Raymond created 55 plates grouped together under the title Essai de reconstitution de mosaïques byzantines (Attempt to reproduce Byzantine mosaics). He portrayed the most famous mosaics of Greek, Italian and Turkish churches. He used photographs that he divided into segments and then scale reproduced down to the finest detail; a technique that would much later be known as “micro-mosaics”.
Sources: en.wikipedia.org
== Plot == An expedition discovered a derelict alien reconnaissance spaceship, which turned out to be fully automated and run by robots. Doctor Pavlysh, a member of the team, accidentally discovers scattered notes written in Russian. It turns out that these were the diary of a Soviet woman, Nadezhda Matveyevna Sidorova. In 1956, she was abducted by this spaceship, whose mission was to collect biological specimens all over the universe, and she has become a living exhibit on the spaceship. Her diary covers the long second half of her life, hence the title of the novel. Nadezhda, the only human occupant, was able to communicate with other captured intelligent non-humanoid species, whom she calls "trepangs" due to their appearance. Together, they organize an escape from the vessel, but Nadezhda Sidorova tragically dies while distracting the guards, allowing the others to escape. Humans later learned that there is a monument to Nadezhda Sidorova at the native planet of the "trepangs", whose memry is cherished there.
=== Skeleton === Sex hormones play an important role in bone growth and maintenance. The effects of hormone therapy on bone health are not fully understood, and may depend on whether hormone therapy is started before or after puberty. Bone density continue to grow and change over time. Significant changes to bone structure have been observed, and transgender women have statistically poorer bone health even before beginning the transition process, possibly due to a lack of physical exercise or other risk factors such as low vitamin D, eating disorders, and substance abuse. Approximately 14% of transgender women suffer from osteoporosis. Transgender women below the age of 50 show increased fracture risk compared to age-matched cisgender women, equal to the risk to cisgender men of equivalent age. Transgender women above the age of 50 have a similar fracture risk to post-menopausal women — higher than that of age-matched cis men. In both cases, trans women's fracture patterns follow that of cis women, suffering long-term stress fractures concentrated in the hip, spine, and arms, typical of chronic low bone mineral density, rather than the fracture patterns typical of external injury suffered by cis men. Current clinical guidelines are for bone health to be monitored regularly throughout the transition process, particularly if risk factors are present. Transgender individuals are encouraged to ingest at least 1g of Calcium and 1000 IU of Vitamin D daily, engage regularly in weight-bearing physical activity, and reduce alcohol and smoking consumption.
Thyroid storm is a severe form of thyrotoxicosis characterized by rapid and often irregular heartbeat, high temperature, vomiting, diarrhea, and mental agitation. Symptoms may not be typical in the young, old, or pregnant. It usually occurs due to untreated hyperthyroidism and can be provoked by infections. It is a medical emergency and requires hospital care to control the symptoms rapidly. The mortality rate in thyroid storm is 3.6-17%, usually due to multi-organ system failure.
Sources: en.wikipedia.org
不是。Semax 是完全人工合成的七肽，自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10)，但序列经过了替换和延长。
Semax 被描述为 ACTH(4-10) 的结构类似物，两者共享部分序列特征。它保留了该片段的部分神经相关活性方向，但去除了完整片段带来的激素释放效应。二者并非同一物质，也不能互相替代。
加入的 Pro-Gly-Pro 三肽被普遍认为能提升分子对蛋白水解酶的稳定性。这种设计让短肽在体内维持时间更长。具体延长的程度以及不同组织中是否一致，文献中仍存在不同报告。
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.