nasal drops comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-07-23. 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 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.
| 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.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
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.
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.
Modern think tanks began as a phenomenon in the United Kingdom in the 19th and early 20th centuries, with most of the rest being established in other English-speaking countries. Before 1945, they focused on the economic issues associated with industrialization and urbanization. During the Cold War, many more American and other Western think tanks were established, which often guided government Cold War policy. Since 1991, more think tanks have been established in non-Western parts of the world. Over half of all think tanks that exist today were established after 1980. As of October 2025, it is said that there are about 6,500 think tanks globally.
By 1982, the perceived passivity of the FARC, together with the relative success of the government's efforts against the M-19 and the ELN, enabled the administration of the Liberal Party's Julio César Turbay Ayala (1978–82) to lift a state-of-siege decree that had been in effect, on and off, for most of the previous 30 years. Under the latest such decree, President Turbay had implemented security policies that, though of some military value against the M-19 in particular, were considered highly questionable both inside and outside Colombian circles due to numerous accusations of military human rights abuses against suspects and captured guerrillas. Citizen exhaustion due to the conflict's newfound intensity led to the election of President Belisario Betancur (1982–1986), a Conservative, with 47% of the popular vote. Betancur directed peace feelers at all the insurgents and negotiated a 1984 cease-fire with the FARC at La Uribe, Meta, after a 1982 release of many guerrillas imprisoned during the previous effort to overpower them. A truce was also arranged with the M-19. The ELN, however, rejected any negotiations and continued to rebuild through the use of extortion and threats, in particular against oil companies of European and U.S. origin. At the same time as these developments, the growing illegal drug trade was becoming increasingly important to all participants in the Colombian conflict. Guerrillas and newly wealthy drug lords had mutually uneven relations, and numerous incidents occurred between them.
=== Kidney === Regenerative capacity of the kidney has been recently explored. The basic functional and structural unit of the kidney is nephron, which is mainly composed of four components: the glomerulus, tubules, the collecting duct and peritubular capillaries. The regenerative capacity of the mammalian kidney is limited compared to that of lower vertebrates. In the mammalian kidney, the regeneration of the tubular component following an acute injury is well known. Recently regeneration of the glomerulus has also been documented. Following an acute injury, the proximal tubule is damaged more, and the injured epithelial cells slough off the basement membrane of the nephron. The surviving epithelial cells, however, undergo migration, dedifferentiation, proliferation, and redifferentiation to replenish the epithelial lining of the proximal tubule after injury. Recently, the presence and participation of kidney stem cells in the tubular regeneration has been shown. However, the concept of kidney stem cells is currently emerging. In addition to the surviving tubular epithelial cells and kidney stem cells, the bone marrow stem cells have also been shown to participate in regeneration of the proximal tubule, however, the mechanisms remain controversial. Studies examining the capacity of bone marrow stem cells to differentiate into renal cells are emerging. Like other organs, the kidney is also known to regenerate completely in lower vertebrates such as fish. Some of the known fish that show remarkable capacity of kidney regeneration are goldfish, skates, rays, and sharks.
Sources: en.wikipedia.org
1911: Polish-born physicist and chemist Marie Curie became the first woman to receive the Nobel Prize in Chemistry, which she received "[for] the discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element". This made her the first person to win the Nobel Prize twice. As of 2022, she is the only woman to win it twice and the only person to win the Nobel Prize in two scientific fields. 1911: Norwegian biologist Kristine Bonnevie became the first woman member of the Norwegian Academy of Science and Letters. 1912: American astronomer Henrietta Swan Leavitt studied the bright-dim cycle periods of Cepheid stars, then found a way to calculate the distance from such stars to Earth. 1912: Canadian botanist and geneticist Carrie Derick was appointed a professor of morphological botany at McGill University. She was the first woman to become a full professor in any department at a Canadian university. 1912: Bengali physician Jamini Sen became the first female Fellow of the Royal Faculty of Physicians and Surgeons of Glasgow. 1913: Regina Fleszarowa became the first Polish woman to receive a PhD in natural sciences. 1913: Izabela Textorisová, the first Slovak female botanist, published "Flora Data from the County of Turiec" in the journal Botanikai Közlemények. Her work uncovered more than 100 previously unknown species of plants from the Turiec area.
== Varieties == Glass noodles are made from a variety of starches. In China, glass noodles are usually made of mung bean starch or sweet potato starch. Chinese varieties made from mung bean starch are called Chinese vermicelli, bean threads, or bean thread noodles. Chinese varieties made from sweet potato starch are called fentiao or hongshufen. Thicker Korean varieties made with sweet potato starch are called sweet potato noodles or dangmyeon. Glass noodles are available in various thicknesses. Wide, flat glass noodle sheets called mung bean sheets are also produced in China. In Korea, napjak-dangmyeon (literally "flat dangmyeon") refers to flat sweet potato noodles.
The fingers may develop almost any deformity depending on which joints are most involved. Specific deformities, which also occur in osteoarthritis, include ulnar deviation, boutonniere deformity (also "buttonhole deformity", flexion of proximal interphalangeal joint and extension of distal interphalangeal joint of the hand), swan neck deformity (hyperextension at proximal interphalangeal joint and flexion at distal interphalangeal joint) and "Z-thumb". "Z-thumb" or "Z-deformity" consists of hyperextension of the interphalangeal joint, fixed flexion, and subluxation of the metacarpophalangeal joint and gives a "Z" appearance to the thumb. The hammer toe deformity may be seen. In the worst case, joints are known as arthritis mutilans due to the mutilating nature of the deformities.
Sources: en.wikipedia.org
Caffeic acid is an organic compound with the formula (HO)2C6H3CH=CHCO2H. It plays a key role in scavenging reactive oxygen species (ROS) generated in energy metabolism. Caffeic acid is also responsible for maintaining normal levels of nitric oxide (NO) within cells. Caffeic acid is a yellow, solid chemical compound that is structurally classified as a hydroxycinnamic acid, and the molecule consists of both phenolic and acrylic functional groups. Caffeic acid is found in all plants as an intermediate in the biosynthesis of lignin, a naturally occurring complex carbohydrate representing the principal components of biomass and its residues. It is chemically unrelated to caffeine; instead, the shared name is related to its presence in coffee.
== Etymology == The name Malaysia is a combination of the word Malays and the Latin-Greek suffix -ia/-ία, which can be translated as 'land of the Malays'. Similar-sounding variants have also appeared in accounts older than the 11th century, as toponyms for areas in Sumatra or referring to a larger region around the Strait of Malacca. The Sanskrit text Vayu Purana, thought to have been in existence since the first millennium CE, mentioned a land named 'Malayadvipa', which was identified by certain scholars as the modern Malay Peninsula. Other notable accounts are by Ptolemy's 2nd-century Geographia, which used the name Malayu Kulon for the west coast of Golden Chersonese, and the 7th-century Yijing's account of Malayu. At some point, the Melayu Kingdom took its name from the Sungai Melayu. Melayu then became associated with Srivijaya, and remained associated with various parts of Sumatra, especially Palembang, where the founder of the Malacca Sultanate is thought to have come from. It is only thought to have developed into an ethnonym as Malacca became a regional power in the 15th century. Islamisation established an ethnoreligious identity in Malacca, with the term Melayu beginning to appear as interchangeable with Melakans. It may have specifically referred to local Malay speakers who were loyal to the Malaccan Sultan. The initial Portuguese use of Malayos reflected this, referring only to the ruling people of Malacca.
Forgive what I said in anger! I will yield to the decree, and only beg one favor, that my children may stay. They shall take to the princess a costly robe and a golden crown, and pray for her protection.
In pharmacokinetics, the effective half-life is the rate of accumulation or elimination of a biochemical or pharmacological substance in an organism; it is the analogue of biological half-life when the kinetics are governed by multiple independent mechanisms. This is seen when there are multiple mechanisms of elimination, or when a drug occupies multiple pharmacological compartments. It reflects the cumulative effect of the individual half-lives, as observed by the changes in the actual serum concentration of a drug under a given dosing regimen. The complexity of biological systems means that most pharmacological substances do not have a single mechanism of elimination, and hence the observed or effective half-life does not reflect that of a single process, but rather the summation of multiple independent processes.
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。
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.