Everything below concerns 鼻内给药. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
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。
| Property | Value | Notes |
|---|---|---|
| Primary research models | Rodent studies | Largest share of published data |
| Reported markers | BDNF and NGF expression | Measured mainly in animal tissue |
| Common administration | Intranasal | Matches the registered formulation |
| Blood residence time | Minutes | Rapid enzymatic degradation |
| Evidence quality | Small trials, limited replication | Noted repeatedly in reviews |
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
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.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
== Catabolism and excretion == Steroids are primarily oxidized by cytochrome P450 oxidase enzymes, such as CYP3A4. These reactions introduce oxygen into the steroid ring, allowing the cholesterol to be broken up by other enzymes into bile acids. These acids can then be eliminated by secretion from the liver in bile. The expression of the oxidase gene can be upregulated by the steroid sensor PXR when there is a high blood concentration of steroids. Steroid hormones, lacking the side chain of cholesterol and bile acids, are typically hydroxylated at various ring positions or oxidized at the 17 position, conjugated with sulfate or glucuronic acid and excreted in the urine.
=== Main === Callum McGowan as Vikram Chamberlain, the active Librarian of 1847 who is released from a timeless imprisonment in 2025 and takes up work as the head Librarian of the Belgrade Annex. He is renowned as one of the greatest swordfighters in the world and carries a sword sheathed in a cane, while his first name is non-Anglophone due to his being born in India. Olivia Morris as: Dr. Lysa Pascal, a mathematician, engineer, and physicist who inherits a castle in Belgrade which hosts an Annex to the Library. She is initially skeptical of the existence of magic but comes to accept it as real while still perceiving it as an untapped branch of science. Anya, General Bogdan Gregor's fiancée and Vikram's lover, who is also Lysa's direct ancestor Bluey Robinson as Connor Green, an expert historian and disgraced university professor-turned-Internet video-streaming conspiracy theorist with a large following, who discovers the Library out of his determination to prove that it exists Jessica Green as Charlie Cornwall, a U.S. military veteran and Guardian candidate who is given a second chance by Jacob Stone and charged with protecting Vikram, Lysa, and Connor
===== Magee-Womens Hospital - UPMC Hamot Campus ===== UPMC Hamot Women's Hospital is a five-story, 165,000 square-foot, 93-bed stand-alone hospital that opened in 2011. The hospital houses obstetrics, neonatology, and gynecology specialities of UPMC Hamot and includes a Level III neonatal intensive care unit. As of October 2013, it also houses the Pediatrics wing of UPMC Hamot.
==== Types of protectants ==== Acetals and Ketals – Removed by acid. Normally, the cleavage of acyclic acetals is easier than of cyclic acetals. Acylals – Removed by Lewis acids. Dithianes – Removed by metal salts or oxidizing agents.
== See also == Golden Crescent Golden Triangle History of Jardine, Matheson & Co. Illegal drug trade in Colombia Mexican drug war Nabidh Opium dollar Opium replacement Protocol for Limiting and Regulating the Cultivation of the Poppy Plant, the Production of, International and Wholesale Trade in, and Use of Opium Psychoactive drug Society for the Suppression of the Opium Trade Morphine Heroin
Sources: en.wikipedia.org
Following the 1494 Treaty of Tordesillas, the land now called Brazil was claimed for the Portuguese Empire on 22 April 1500, with the arrival of the Portuguese fleet commanded by Pedro Álvares Cabral. Along the coast, the Portuguese encountered various Indigenous communities, most of whom spoke languages of the Tupi–Guarani family. Though the first settlement, São Vicente, was founded in 1532, colonization effectively began in 1534, when King John III of Portugal divided the territory into the fifteen private and autonomous captaincies. However, the decentralized and unorganized captaincy system proved unsuccessful, and in 1549 the Portuguese king restructured them into the Governorate General of Brazil in the city of Salvador, which became the capital of a single and centralized Portuguese colony in South America. In the first two centuries of colonization, Indigenous and European groups lived in constant war, establishing opportunistic alliances in order to gain advantages against each other.
== Oxford == Oxford University Press, which publishes the Oxford English Dictionary and many other dictionaries, announces an Oxford Dictionaries UK Word of the Year and an Oxford Dictionaries US Word of the Year; sometimes these are the same word and simply dubbed Word of the Year. The word need not have been coined within the year or twelve months but it does need to have become prominent or notable during that time. There is no guarantee that the Word of the Year will be included in any Oxford dictionary if it's not present. The Oxford Dictionaries Words of the Year are selected by editorial staff from each of the Oxford dictionaries. The selection team is made up of lexicographers and consultants to the dictionary team, and editorial, marketing, and publicity staff.
For x = 1 and y = 2 the empirical formula H2S2O7 for disulfuric (pyrosulfuric) acid is obtained. Pure disulfuric acid is a solid at room temperature, melting at 36 °C and rarely used either in the laboratory or industrial processes — although some research indicates that pure disulfuric acid has never been isolated yet.
In soil, microorganisms that reside in the rhizosphere (a zone that includes the root surface and the soil that adheres to the root after gentle shaking) carry out nitrogen fixation, converting nitrogen gas to nitrogenous compounds. This serves to provide an easily utilisable form of nitrogen for many plants, which cannot fix nitrogen themselves. Many other bacteria are found as symbionts in humans and other organisms. For example, the presence of over 1,000 bacterial species in the normal human gut flora of the intestines can contribute to gut immunity, synthesise vitamins, such as folic acid, vitamin K and biotin, convert sugars to lactic acid (see Lactobacillus), as well as fermenting complex undigestible carbohydrates. The presence of this gut flora also inhibits the growth of potentially pathogenic bacteria (usually through competitive exclusion) and these beneficial bacteria are consequently sold as probiotic dietary supplements. Nearly all animal life is dependent on bacteria for survival as only bacteria and some archaea possess the genes and enzymes necessary to synthesise vitamin B12, also known as cobalamin, and provide it through the food chain. Vitamin B12 is a water-soluble vitamin that is involved in the metabolism of every cell of the human body. It is a cofactor in DNA synthesis and in both fatty acid and amino acid metabolism. It is particularly important in the normal functioning of the nervous system via its role in the synthesis of myelin.
== Rationale == The primary objectives of general anesthesia include inducing unconsciousness, providing analgesia, facilitating muscle relaxation, and the temporary suppression of motor reflexes. Achieving muscle paralysis is often necessary for certain surgical procedures. Depending on the procedure to be undertaken, blocking transmission of nociception (autonomic nervous system responses to noxious stimuli and its cardiac and hemodynamic effects – even in the absence of conscious pain perception), may be the aim of analgesia. Amnesia – induced through an altered state of consciousness – may be adequate or preferred over total unconsciousness. The physiological stability of the patient has to be maintained while all this is achieved. Balanced anesthesia is employed in a range of surgical procedures to optimize patient safety and comfort. It is commonly used in major abdominal surgeries, such as bowel resections, liver surgery, and gastric bypass, where deep anesthesia and muscle relaxation are required. In cardiac surgery, balanced anesthesia facilitates precise control of heart rate and blood pressure, which is critical during these complex procedures. Additionally, orthopedic surgeries, including hip and knee replacements, utilize this approach to enhance muscle relaxation and pain management. Gynecological surgeries, such as hysterectomies and laparoscopic procedures, also benefit from balanced anesthesia to maintain patient stability and comfort throughout the operation.
Sources: en.wikipedia.org
The main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.
The compound is registered as a medicine in Russia, so clinical work has concentrated there. Trials elsewhere are few and generally small. This geographic concentration is a recognized limitation in evidence reviews.
Some fraction may reach the central nervous system through olfactory pathways, and this is often cited as the rationale for the nasal route. The size of that fraction in humans is not well quantified. Blood concentrations after nasal dosing are low, which complicates measurement.
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。