The short version of 鼻内给药 fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-12-05 and is reviewed periodically as new material appears.
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。
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 |
|---|---|---|
| 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 heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
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。
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。
Aarts, Mongolian fermented curd, eaten as a dried snack or reconstituted as a hot beverage Chongos zamoranos, a dessert prepared with milk curdled with sugar and cinnamon Cuajada (or Coalhada), usually sweetened and eaten for breakfast or dessert, popular in Spain and Central America Curd snack, a snack popular in the Baltic states Çökelek, a form of fermented buttermilk or yogurt curd from Turkey Farmer cheese Hoop cheese Key lime pie, prepared by curdling condensed milk Kesú Paraguay, a Paraguayan formed cottage cheese Kurt or Qurut, Central Asian cheese curd Leipäjuusto, Finnish cheese Ostkaka, Swedish style cheese cake, some call it a Swedish national dish Paskha, a Russian Easter dessert made of Tvorog Ricotta, an Italian whey cheese Skyr, Icelandic curd Tofu, the coagulated product from soy milk, from East and Southeast Asian countries. Túró Rudi, a Hungarian chocolate bar with curd Urdă, a Balkan fresh white cheese made from whey. List of dairy products
== External links == The chemical logic behind the pentose phosphate pathway Pentose+Phosphate+Pathway at the U.S. National Library of Medicine Medical Subject Headings (MeSH) Pentose phosphate pathway Map – Homo sapiens
In biochemistry, a Ramachandran plot (also known as a Rama plot, a Ramachandran diagram or a [φ,ψ] plot), originally developed in 1963 by G. N. Ramachandran, C. Ramakrishnan, and V. Sasisekharan, is a way to visualize energetically allowed regions for backbone dihedral angles (also called as torsional angles, phi and psi angles) φ against ψ of amino acid residues in protein structure. The figure on the left illustrates the definition of the φ and ψ backbone dihedral angles (called φ and φ' by Ramachandran). The ω angle at the peptide bond is normally 180°, since the partial-double-bond character keeps the peptide bond planar. The figure in the top right shows the allowed φ,ψ backbone conformational regions from the Ramachandran et al. 1963 and 1968 hard-sphere calculations: full radius in solid outline, reduced radius in dashed, and relaxed tau (N-Cα-C) angle in dotted lines. Because dihedral angle values are circular and 0° is the same as 360°, the edges of the Ramachandran plot "wrap" right-to-left and bottom-to-top. For instance, the small strip of allowed values along the lower-left edge of the plot are a continuation of the large, extended-chain region at upper left.
Sources: en.wikipedia.org
=== Direct printing === Two different methods for the direct application of indigo were developed in England in the 18th century and remained in use well into the 19th century. The first method, known as "pencil blue" because it was most often applied by pencil or brush, could be used to achieve dark hues. Arsenic trisulfide and a thickener were added to the indigo vat. The arsenic compound delayed the oxidation of the indigo long enough to paint the dye onto fabrics.
Trans fats occur in meat and dairy products from ruminants. For example, butter contains about 3% trans fat by weight. These naturally occurring trans fats include conjugated linoleic acid (CLA) and vaccenic acid (trans-11 18:1). They arise from the action of bacteria in the rumen. Polyunsaturated fats are toxic to the rumen-based bacteria, which detoxify the fats by changing some cis-double bonds to trans-double bonds. In contrast to industrially produced trans fats, this bacterial process produces only a few specific isomers. Conjugated trans fatty acids such as CLA are exempt from counting as trans fat in the US. The Codex Alimentarius includes an analogous exclusion. As industrial sources of trans fats are eliminated, increased attention focuses on ruminant derived trans fats. Not all ruminant-derived trans fats are innocuous like vaccenic acid and its metabolite rumenic acid (cis-9-trans-11 CLA / 18:2). In particular, trans-10 18:1 is not turned into a conjugated linoleic acid by humans. It appears to have health consequences comparable to trans fats of industrial origin.
The U.S. and Canadian Dietary Reference Intake review for protein concluded that there was not sufficient evidence to establish a Tolerable upper intake level, i.e., an upper limit for how much protein can be safely consumed. When amino acids are in excess of needs, the liver takes up the amino acids and deaminates them, a process converting the nitrogen from the amino acids into ammonia, further processed in the liver into urea via the urea cycle. Excretion of urea occurs via the kidneys. Other parts of the amino acid molecules can be converted into glucose and used for fuel. When food protein intake is periodically high or low, the body tries to keep protein levels at an equilibrium by using the "labile protein reserve" to compensate for daily variations in protein intake. However, unlike body fat as a reserve for future caloric needs, there is no protein storage for future needs. Excessive protein intake may increase calcium excretion in urine, occurring to compensate for the pH imbalance from oxidation of sulfur amino acids. This may lead to a higher risk of kidney stone formation from calcium in the renal circulatory system. One meta-analysis reported no adverse effects of higher protein intakes on bone density. Another meta-analysis reported a small decrease in systolic and diastolic blood pressure with diets higher in protein, with no differences between animal and plant protein. High protein diets have been shown to lead to an additional 1.21 kg of weight loss over a period of 3 months versus a baseline protein diet in a meta-analysis.
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。
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.