The short version of 免疫调节 fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-07-05 and is reviewed periodically as new material appears.
20世纪70年代，研究者从胸腺提取物中纯化出多种小肽，Tα1是其中被较早表征的一种。最初的制备依赖组织匀浆和层析步骤，产量低且成分复杂。随着固相肽合成技术成熟，实验室和工业界能够生产与天然序列一致的合成版本。合成肽的纯度可达95%以上，并可通过反相高效液相色谱和质谱进行鉴定。这一转变使研究不再依赖动物胸腺来源。
市售的胸腺素α1通常以冻干粉形式提供，溶解后用于注射。其氨基酸组成包括多个酸性残基，因此在中性pH下带负电荷。该肽可溶于水和生理盐水，但在有机溶剂中溶解度有限。储存条件通常为冻干状态下负20摄氏度，溶解后需冷藏并避免反复冻融。常见的同义词包括胸腺肽α1、thymalfasin和Tα1。
胸腺素α1（thymosin alpha 1，Tα1）是一种由28个氨基酸组成的酸性肽，N端被乙酰化，分子量约为3108道尔顿。该肽最早从牛胸腺组织提取物中分离，属于胸腺素组分5的一个成分。其序列在不同哺乳动物中高度保守，提示其具有基本的生物学功能。名称中的“α1”指其在电泳中的迁移位置，并非表示亚型编号。它既存在于胸腺，也存在于脾脏和淋巴结等免疫组织。
Several factors accelerate degradation: alkaline pH, elevated temperature, exposure to oxidants, and the presence of residual moisture. Deamidation of asparagine residues and oxidation of methionine are the most commonly reported degradation routes. Because the peptide lacks disulfide bonds, it does not undergo the thiol-related aggregation seen in some other biologics, but physical aggregation can still occur at high concentration. Stability data are product-specific, and extrapolating shelf life between formulations is not reliable.
Lyophilized thymosin alpha-1 is generally stored at or below minus twenty degrees Celsius, protected from moisture and light. Short-term handling at ambient temperature is possible for dry powder, but reconstituted solutions degrade faster and are usually kept at two to eight degrees Celsius with a defined expiry of days rather than weeks. Repeated freeze-thaw cycles should be avoided because they promote aggregation and loss of potency. Exact limits depend on the formulation and should follow the supplier's documentation.
| Property | Value | Notes |
|---|---|---|
| 化学分类 | 线性肽 | 由28个氨基酸组成 |
| 分子量 | 约3108 Da | 合成版本一致 |
| 外观 | 白色至类白色粉末 | 冻干品 |
| 溶解度 | 易溶于水 | 微溶于有机溶剂 |
| 储存温度 | -20°C（冻干） | 溶解后2-8°C |
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Findings across trials are mixed; some report changes in selected immune markers, while others find no clear clinical benefit. Many studies are small and define outcomes differently, which limits comparison. Regulatory approval is confined to a few countries, and the compound is not an approved drug in the United States or most of Europe.
Overall evidence quality varies considerably. A large share of published reports come from single centers, rely on surrogate immunological markers, or lack adequate control groups. Systematic reviews have highlighted this heterogeneity as a barrier to pooling results. Open questions include which patients, if any, might benefit, what treatment duration is appropriate, and whether any effect is independent of standard care. The peptide is often described as an immune modulator rather than a therapy for one disease, which complicates confirmatory trial design.
Identity and purity are assessed with a small set of standard peptide methods. Reversed-phase high-performance liquid chromatography separates the main peak from truncated or oxidized species, and its area percentage is the usual purity measure. Mass spectrometry confirms the observed molecular mass against the expected value, while amino acid analysis or peptide mapping checks composition and sequence. Specifications for research-grade material are often stated as 95 percent or higher, though the exact limit depends on the supplier and the intended use.
Laboratory supplies of the peptide usually arrive as a lyophilized powder in sealed vials. The powder is hygroscopic, so a vial should be allowed to reach room temperature before it is opened to prevent condensation on the contents. Weighing and transfer are best performed in a low-humidity environment with clean tools. Once dissolved, the solution should be mixed gently rather than vortexed, because foaming and shear can reduce recovery of the peptide.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
The peptide is generated in cells by cleavage of prothymosin alpha, a larger acidic protein encoded by the PTMA gene. Prothymosin alpha is expressed in many tissues, not only in the thymus, and its functions include nuclear roles in chromatin-related processes. The 28-residue fragment corresponds to the N-terminal portion of that precursor. How the cleavage occurs and how the fragment's concentration is regulated remain open questions; circulating amounts are small and difficult to measure reliably with routine assays.
临床研究将Tα1用于慢性病毒感染、肿瘤辅助治疗和疫苗佐剂等场景。部分试验报告了免疫学指标改善，但临床终点获益在不同研究中并不一致。系统综述指出，研究间在人群、剂量和联合方案上差异较大，难以汇总结论。因此，Tα1的确切临床地位仍属开放问题，需要更多高质量随机对照试验来澄清。其机制研究也需从体外实验向体内模型推进。
胸腺素α1对免疫系统的影响涉及多种细胞类型。研究表明，它可促进未成熟T细胞向成熟T细胞分化，并增强T细胞对抗原刺激的增殖反应。树突状细胞在Tα1存在下表达更高水平的共刺激分子，从而更有效地呈递抗原。此外，自然杀伤细胞的活性也观察到上升。这些效应并非直接杀伤病原体，而是调节宿主免疫应答的强度与方向。
== Parasites == Parasites include Plasmodium berghei (for which it also serves as a vector), and the bioinsecticides/entomopathogenic fungi Metarhizium robertsii and Beauveria bassiana. All three of these parasites combine with insecticides to reduce fitness – see § Insecticides below. CRISPR/Cas9 and U6-gRNA are increasingly (as of 2020) being used together for knockout experiments in mosquitoes. Dong et al., 2018 develops and presents a new U6-gRNA+Cas9 technique in An. gambiae, and utilizes it to knock out fibrinogen related protein 1 (FREP1), thereby severely reducing infection of the mosquito by P. berghei and P. falciparum. However this also demonstrates the centrality of FREP1 to the insect's success, impairing all measured activities across all life stages. Yang et al., 2020 uses the Dong method to do the same with mosGILT, also severely reducing Plasmodium infection of the mosquito but also finding a vital life process is impaired, in mosGILT's case ovary development.
On February 3, 1867, the 14-year-old Prince Mutsuhito succeeded his father, Emperor Kōmei, to the Chrysanthemum Throne as the 122nd emperor. This coincided with pressure on the ruling shogunate to modernize Japan, combining modern advances with traditional values. Mutsuhito was sympathetic to these ideas, leading to a call for the restoration of the governing power to the emperor. On November 9, 1867, then-shōgun Tokugawa Yoshinobu tendered his resignation to the Emperor, and "put his prerogatives at the Emperor’s disposal", formally stepping down ten days later. Imperial restoration occurred the next year on January 3, 1868, with the formation of the new government. The fall of Edo in the summer of 1868 marked the end of the Tokugawa shogunate, and a new era, Meiji, was proclaimed. The first reform was the promulgation of the Five Charter Oath in 1868, a general statement of the aims of the Meiji leaders to boost morale and win financial support for the new Meiji government. Its five provisions consisted of:
=== Meiosis === Meiotic recombination in D. melanogaster appears to be employed in repairing damage in germ-line DNA as indicated by the findings that meiotic recombination is induced by the DNA damaging agents ultraviolet light and mitomycin C.
Prokaryotes: 50S ribosomal subunit, 23S rRNA Eukaryotes: 60S ribosomal subunit, 28S rRNA See also: Ribosomal RNA § Subunits and associated ribosomal RNA, mitochondrial ribosome, and Chloroplast § Chloroplast ribosomes. Peptidyl transferases are not limited to translation, but there are relatively few enzymes with this function.
There are many geological issues concerning the rivers and streams of the Appalachians. In spite of the existence of the Great Appalachian Valley, many of the main rivers are transverse to the mountain system axis. The drainage divide of the Appalachians follows a tortuous course that crosses the mountainous belt just north of the New River in Virginia. South of the New River, rivers head into the Blue Ridge, cross the higher Unakas, receive important tributaries from the Great Valley, and traversing the Cumberland Plateau in spreading gorges (water gaps), escape by way of the Cumberland River and the Tennessee River rivers to the Ohio River and the Mississippi River, and thence to the Gulf of Mexico. In the central section, north of the New River, the rivers, rising in or just beyond the Valley Ridges, flow through great gorges to the Great Valley, and then across the Blue Ridge to tidal estuaries penetrating the coastal plain via the Roanoke River, James River, Potomac River, and Susquehanna River. In the northern section, the height of land lies on the inland side of the mountainous belt, and thus the main lines of drainage run from north to south, exemplified by the Hudson River. However, the valley through which the Hudson River flows was cut by the gigantic glaciers of the ice ages—the same glaciers that deposited their terminal moraines in southern New York and formed the east–west Long Island.
Sources: en.wikipedia.org
== Happiness == World Happiness Report 2017: Thailand ranked 32 of 155 nations (1=happiest). Other ASEAN states ranked were: Singapore, 26; Malaysia, 42; Philippines, 72; Indonesia, 81; Vietnam, 94; Myanmar, 114; Cambodia, 129. World Happiness Index 2016: Ranked 140 nations on four criteria. Thailand ranked 9 of 140 (1=happiest). Other ASEAN nations in the study ranked: Vietnam, 5; Indonesia, 16; Philippines, 20; Malaysia, 46; Cambodia, 74; Myanmar, 81. World Happiness Report 2015: Thailand ranks 34 of 158 nations in the third issuance of the World Happiness Report.
=== Distillation === Distilled water is produced by a process of distillation. Distillation involves boiling the water and then condensing the vapor into a clean container, leaving solid contaminants behind. Distillation produces very pure water. A white or yellowish mineral scale is left in the distillation apparatus, which requires regular cleaning. Distilled water, like all purified water, must be stored in a sterilized container to guarantee the absence of bacteria. For many procedures, more economical alternatives are available, such as deionized water, and are used in place of distilled water.
== Applications == NanoSIMS can capture the spatial variability of isotopic and elemental measurements of sub-micron areas, grains or inclusions from geological, materials science and biological samples. This instrument can characterise nanostructured materials with complex composition that are increasingly important candidates for energy generation and storage.
== Mechanism of action == Nitrovasodilators are prodrugs that donate NO by various mechanisms. Nitrates undergo chemical reduction, likely mediated by enzymes. Molsidomine and nitroprusside already contain nitrogen in the right oxidation state (+2) and liberate NO without the aid of enzymes. NO stimulates the soluble form of the enzyme guanylate cyclase in the smooth muscle cells of blood vessels. Guanylate cyclase produces cyclic guanosine monophosphate (cGMP) from guanosine triphosphate (GTP). cGMP in turn activates cyclic nucleotide-dependent protein kinase G, which phosphorylates various proteins that play a role in decreasing intracellular calcium levels, leading to relaxation of the muscle cells and thus to dilation of blood vessels. The most important effect in angina is the widening of veins, which increases their capacity to hold blood ("venous pooling") and reduces the pressure of the blood returning to the heart (the preload). Widening of the large arteries also reduces the pressure against which the heart has to pump, the afterload. Lower preload and afterload result in the heart needing less energy and thus less oxygen. Besides, NO donated by nitrovasodilators can reduce coronary spasms, increasing the heart's oxygen supply. PDE5 inhibitors block deactivation of cGMP by the enzyme phosphodiesterase-5. In combination with the increased cGMP production caused by nitrovasodilators, this leads to high concentrations of cGMP, extensive venous pooling, and potentially life-threatening hypotension.
Sources: en.wikipedia.org
In April 2015, Hardee's announced the opening of its 300th restaurant in the Middle East with longtime franchisee, The Americana Group. In 2015, Nation's Restaurant News ranked Hardee's as the No. 28 foodservice chain by sales in the United States through 2011. Carl's Jr. was ranked at No. 37. Combined sales would rank the two at No. 15. In 2013, QSR listed Hardee's at No. 20 and Carl's Jr. at No. 24; if combined they would have been listed at No. 14. In July 2015, Hardee's announced that it would be offering The All-Natural Burger, which launched at sister-chain Carl's Jr. restaurants in December 2014. As of March 2016, CKE has a total of 3,664 franchised or company-operated restaurants in 44 states and 37 foreign countries and U.S. territories. The Hardee's in Millvale, Pennsylvania closed suddenly on August 25, 2025, after 52 years, marking the withdrawal of Hardee's from Greater Pittsburgh. Hardee's, which had entered Pennsylvania with the Sandy's purchase a year before the Millvale location opened, retains one location in Western Pennsylvania in Waynesburg (near the West Virginia border) while the rest in Pennsylvania are in South Central Pennsylvania. In 2026, Hardee's franchise operator Boddie-Noell announced that a location in Virginia Beach would close and be converted to a concept called Biscuits & Bird that focused on breakfast biscuits and chicken tenders, with the restaurant opening under the new branding in July 2026. On July 9, 2026, Superior Star LLC, a Phoenix-based Hardee's franchisee operating in the Midwest, filed for Chapter 11 bankruptcy protection.
The Wagler's pit viper is sexually dimorphic: the females grow to approximately 1 m (39+1⁄4 in) in total length (including tail), their bodies being black with yellow stripes. Males, on the other hand, typically do not exceed 75 cm (29+1⁄2 in). Males have large triangular-shaped heads, with relatively thin green bodies. They are almost entirely arboreal, and their tails are prehensile to aid in climbing. They are found in a wide variety of colors and patterns, often referred to as "phases". In the past, some researchers classified the different phases as subspecies. The phases vary greatly from having a black or brown coloration as a base, with orange and yellow banding, to others having a light green as the base color, with yellow or orange banding, and many variations therein.
Concurrent with the work of Rutherford, Geiger, and Marsden, the radiochemist Frederick Soddy at the University of Glasgow was studying chemistry-related problems on radioactive materials. Soddy had worked with Rutherford on radioactivity at McGill University. By 1910, about 40 different radioactive elements, referred to as radioelements, had been identified between uranium and lead, although the periodic table only allowed for 11 elements. Every attempt to chemically isolate the radioelements mesothorium or thorium X from radium failed. Soddy concluded that these element were chemically the same element. At the suggestion of Margaret Todd, Soddy called these chemically identical elements isotopes. In 1913, Soddy and theorist Kazimierz Fajans independently found the displacement law, that an element undergoing alpha decay will produce an element two places to the left in the periodic system and an element undergoing beta decay will produce an element one place to the right in the periodic system. For his study of radioactivity and the discovery of isotopes, Soddy was awarded the 1921 Nobel Prize in Chemistry.
The cellular reproduction process of meiosis was discovered by Oscar Hertwig in 1876. Mitosis was discovered several years later in 1882 by Walther Flemming. Hertwig studied sea urchins, and noticed that each egg contained one nucleus prior to fertilization and two nuclei after. This discovery proved that one spermatozoon could fertilize an egg, and therefore proved the process of meiosis. Hermann Fol continued Hertwig's research by testing the effects of injecting several spermatozoa into an egg, and found that the process did not work with more than one spermatozoon. Flemming began his research of cell division starting in 1868. The study of cells was an increasingly popular topic in this time period. By 1873, Schneider had already begun to describe the steps of cell division. Flemming furthered this description in 1874 and 1875 as he explained the steps in more detail. He also argued with Schneider's findings that the nucleus separated into rod-like structures by suggesting that the nucleus actually separated into threads that in turn separated. Flemming concluded that cells replicate through cell division, to be more specific mitosis. Matthew Meselson and Franklin Stahl are credited with the discovery of DNA replication. Watson and Crick acknowledged that the structure of DNA did indicate that there is some form of replicating process. However, there was not a lot of research done on this aspect of DNA until after Watson and Crick. People considered all possible methods of determining the replication process of DNA, but none were successful until Meselson and Stahl.
retention times of trailing and heading n-alkanes, respectively. NOTE: TPGC index does depend on temperature program, gas velocity and the column used ! ASTM method D6730 defines the temperature programmed chromatography Kovats index equation:
Sources: en.wikipedia.org
它不是经典的内分泌激素，而是一种免疫调节肽。其作用主要通过局部免疫细胞间的信号传递实现，而非经血液循环作用于远隔器官。
天然胸腺素α1主要从胸腺组织提取，也可在脾脏和淋巴结中检出。目前研究和临床使用的多为化学合成版本，不再依赖动物组织。
胸腺素组分5是牛胸腺提取物的粗组分，包含多种肽。胸腺素α1是其中一种被纯化和表征的单一肽，具有明确的28个氨基酸序列。
Dry lyophilized powder tolerates short ambient exposure during handling and shipping. Long-term room-temperature storage is not recommended because moisture uptake and slow degradation can occur over months. Storage at minus twenty degrees Celsius is the common practice for extended periods.