The short version of 肽聚集 fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-06-20. Anything still debated is marked as such rather than presented as settled.
Large randomised trials in adults with type 2 diabetes and in adults with obesity have reported reductions in body weight and improvements in several cardiovascular risk markers. One outcome trial found a lower incidence of major adverse cardiovascular events in participants with diabetes and established cardiovascular disease. Gastrointestinal effects such as nausea and vomiting are the most frequently reported adverse events and often diminish over time. Changes in lean body mass during weight loss are an area of ongoing investigation. Effects in adolescents and in pregnancy are less well characterised, and current labelling advises against use during pregnancy.
Semaglutide is a synthetic peptide analogue of glucagon-like peptide-1, a gut hormone released after nutrient intake. The molecule contains 31 amino acid residues and differs from the native sequence at several positions. A non-natural residue at position eight resists the enzyme that normally truncates the hormone, while a lysine-linked fatty diacid side chain promotes binding to serum albumin. These two modifications extend the circulating half-life from minutes to roughly one week. The peptide is produced by solid-phase synthesis followed by selective acylation, and its identity and purity are confirmed by spectrometric and chromatographic techniques.
The primary target is the GLP-1 receptor, a class B G protein-coupled receptor expressed on pancreatic beta cells, in the gut, and in several brain regions. Receptor activation raises intracellular cyclic AMP, which potentiates glucose-dependent insulin secretion and lowers glucagon release when blood glucose is elevated. Signalling in the hypothalamus and brainstem is associated with reduced appetite and slower gastric emptying. Because the insulinotropic effect depends on prevailing glucose levels, the hypoglycaemic risk of the peptide alone is described as low in most study settings. The relative contribution of peripheral and central actions remains an active research question.
关于降解产物的免疫原性风险，文献中仍有讨论空间。体外聚集水平与临床免疫反应之间的定量关系尚未确立。多数公开研究只报告理化指标，缺少长期随访的对应数据。这一问题在生物类似物比对中尤其受到关注。
市售注射用制剂通常要求在二至八摄氏度冷藏保存，并避免光照与冻结。部分多剂量笔在首次使用后允许在不超过三十摄氏度的环境中存放有限周数，具体期限由辅料与防腐剂体系决定。反复冻融会促进肽链聚集并改变可见颗粒计数，因此应予避免。冻干粉末在干燥、避光、低温条件下更为稳定。溶液配制后宜使用低吸附容器，以减少肽类在塑料或玻璃表面的损失。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Acylated GLP-1 receptor agonist | 31-residue synthetic peptide |
| Molecular formula | C187H291N45O59 | established for the free peptide |
| Appearance | White to off-white powder | as supplied before formulation |
| Solubility | Freely soluble in water | aqueous buffers near neutral pH |
| Typical storage | 2 to 8 degrees Celsius, protected from light | powder and solution forms differ in shelf life |
LCFAs are important to cells as they can act as stored sources of energy, signaling molecules, and as building blocks for cell membranes. Transporting these LCFAs through the cell so that they may serve these many roles is thus imperative for the cell to do. The carnitine shuttle evolved as a way for cells to be able transport LCFAs to the many places they are needed for these roles. The LCFA's are synthesized, or absorbed. Carnitine is similarly either synthesized, or absorbed. The acyl-CoA comes from Acyl-CoA synthetase. The shuttle's mechanism is as follows:
They are used in expansive cements, in ultra-high early strength cements, and in "low-energy" cements. Hydration produces ettringite, and specialized physical properties (such as expansion or rapid reaction) are obtained by adjustment of the availability of calcium and sulfate ions. Their use as a low-energy alternative to Portland cement has been pioneered in China, where several million tonnes per year are produced. Energy requirements are lower because of the lower kiln temperatures required for reaction, and the lower amount of limestone (which must be endothermically decarbonated) in the mix. In addition, the lower limestone content and lower fuel consumption leads to a CO2 emission around half that associated with Portland clinker. However, SO2 emissions are usually significantly higher. "Natural" cements corresponding to certain cements of the pre-Portland era, are produced by burning argillaceous limestones at moderate temperatures. The level of clay components in the limestone (around 30–35%) is such that large amounts of belite (the low-early strength, high-late strength mineral in Portland cement) are formed without the formation of excessive amounts of free lime. As with any natural material, such cements have highly variable properties. Geopolymer cements are made from mixtures of water-soluble alkali metal silicates, and aluminosilicate mineral powders such as fly ash and metakaolin. Polymer cements are made from organic chemicals that polymerise. Producers often use thermoset materials.
Due to its broad availability, speed, and relatively low cost, it continues to be a common first-line tool in radiologic evaluation. Despite advances in CT, MRI, and other imaging techniques, there are many conditions in which traditional radiographs remain helpful in diagnosis. These include arthritis, pneumonia, bone tumors, fractures, congenital skeletal anomalies, and certain types of kidney stones. Mammography and DXA are two applications of low-energy projectional radiography, used for the evaluation of breast cancer and osteoporosis, respectively.
A Morpholino, also known as a phosphorodiamidate Morpholino oligomer (PMO), is a nucleic acid analog whose backbone consists of methylenemorpholine rings linked through phosphorodiamidate groups, in contrast to the sugars linked through phosphates found in natural nucleic acids. Synthetic oligomers of Morpholinos are used in molecular biology to modify gene expression. Morpholinos block access of other molecules to small (~25 base) specific sequences of the base-pairing surfaces of ribonucleic acid (RNA). Morpholinos are used as research tools for reverse genetics by knocking down gene function. Morpholinos are in development as pharmaceutical therapeutics targeted against pathogenic organisms such as bacteria or viruses and genetic diseases. A Morpholino-based drug eteplirsen from Sarepta Therapeutics received accelerated approval from the US Food and Drug Administration in September 2016 for the treatment of some mutations causing Duchenne muscular dystrophy, although the approval process was mired in controversy. Other Morpholino-based drugs golodirsen, viltolarsen, and casimersen (also for Duchenne muscular dystrophy) were approved by the FDA in 2019–2021. "Morpholino" is often capitalized to distinguish the nucleic acid type from other chemicals containing a six-membered morpholine ring, but this usage is not consistent across scientific literature. Vivo-Morpholinos and PPMO are modified forms of Morpholinos with chemical groups covalently attached to facilitate entry into cells.
(The Ruthenian part, Subcarpathian Rus, made also an attempt to declare its sovereignty as Carpatho-Ukraine but only with ephemeral success since the area was soon annexed by Hungary.) Although "Henlein and the SdP had become accessories in Hitler's escalating campaign to annex the Sudetenland to the German Reich" by the summer of 1938, the supporters of the SdP supported autonomy within Czechoslovakia rather than annexation into Germany. Contemporary reports of The Times found that there was a "large number of Sudetenlanders who actively opposed annexation", and that the pro-German policy was challenged by the moderates within the SdP as well; according to Wickham Steed, over 50% of Henlein's supporters favoured greater autonomy within Czechoslovakia rather than joining Germany. Sudeten German historian Emil Franzel argues that the mainstream wing of Henlein's party was "not striving for annexation to Germany, but for genuine autonomy", and the majority of negotiators who conducted talks with Hodža and Beneš belonged to the pro-autonomy wing and were unaware of Henlein's agreements with Hitler. Part of the borderland had an ethnic Polish majority and was invaded and annexed by Poland in 1938.
Sources: en.wikipedia.org
== Retirement == On average, women in France receive pensions that are 41.7% lower than those received by men when considering only direct entitlement pensions. This gap is reduced to approximately 29% when accounting for child-related bonuses and survivor's pensions. Maternity leave daily allowances paid prior to 2012 are not included in the calculation of average annual income for pension purposes, which contributes to the pension gap.
===== Mexico ===== In March 2023, Brazilian presidential office said Mexican president Andres Manuel Lopez Obrador invited Lula to visit Mexico and discuss expanding economic cooperation between Mexico and Brazil including the removal of trade tariffs between their countries. In September 2024, Lula visited Mexico and separately met with President Andrés Manuel López Obrador and president-elect Claudia Sheinbaum. He later attended Sheinbaum's inauguration and joined the Brazilian-Mexican business forum which 400 business people attended.
This occurred due to DOM being publicly distributed for free in the form of high-dose tablets by LSD distributor Owsley Stanley, who had personally learned of DOM from Shulgin. It is unclear why Shulgin provided information about DOM to Stanley, since doing so had the potential to risk Shulgin's professional career and the DOET clinical studies. One possibility is that Dow Chemical Company was not further looking into DOM and Shulgin thought that it was a promising drug that would otherwise be forgotten. In any case, street use of DOM was short-lived because the tablets caused a public health crisis due to them often producing very long durations (up to 3–4 days), intense experiences, worrying physical side effects, and hospitalizations. DOM was first reported on in the media and scientific literature in 1967 as a result of the crisis. DOM became illegal in the United States in 1968. Dow Chemical Company terminated its clinical research program on DOET due to the DOM public health crisis. DOET was subsequently first described in the literature by Snyder and colleagues in 1968. Snyder continued to be interested in DOET as a potential medicine, but it was never further developed. Snyder also described 2,5-dimethoxyamphetamine (2,5-DMA), which had been synthesized and tested by Shulgin, in the literature in 1968. DOM and DOET were further described in the scientific literature by Shulgin in 1969. In addition, Shulgin discussed DOM, DOET, TMA-2, and 2,5-DMA in a book chapter on hallucinogens published in 1970.
Benninghoven graduated from the University of Cologne in 1961 where he worked with Fritz Kirchner (1896–1967) and completed his habilitation in surface physics in Cologne two years later. He first worked as professor in Cologne from 1965 to 1973 until he moved to a full professor position in experimental physics at the University of Münster in 1972. He worked on static secondary ion mass spectrometry (SIMS) and its applications, and developed SIMS instruments. In 1989 he co-founded IonTOF, a company that became a world-leader in TOF-SIMS instrumentation. He has written over 300 scientific articles and several books on the topic of SIMS, many of which have become reference works on SIMS. For his work, he has received the Technology Transfer prize (German Ministry of Education and Research) and the 1984 Gaede-Langmuir Prize (American Vacuum Society) for the development of concepts and instrumentation in static secondary ion mass spectrometry and the demonstration of its usefulness in manifold applications. In 1990 he shared the Fritz-Pregl-Medaille of the Austrian Society of Analytical Chemistry with Wilhelm Simon. From 1977 to 1983, he was president of the German Vacuum Society (part of the German Physical Society).
In another 2018 experiment, it was possible to perform a first laser-spectroscopic characterization of the nuclear properties of 229mTh. In this experiment, laser spectroscopy of the 229Th atomic shell was conducted using a 229Th2+ ion cloud with 2% of the ions in the nuclear excited state. This allowed probing for the hyperfine shift induced by the different nuclear spin states of the ground and the isomeric state. In this way, a first experimental value for the magnetic dipole and the electric quadrupole moment of 229mTh could be inferred. In 2019, the isomer's excitation energy was constrained to 8.28±0.17 eV based on the direct detection of internal conversion electrons and a secure population of 229mTh from the nuclear ground state was achieved by excitation of the 29 keV nuclear excited state via synchrotron radiation. Additional measurements by a different group in 2020 produced a figure of 8.10±0.17 eV (153.1±3.2 nm wavelength). Combining these measurements, the expected transition energy is 8.12±0.11 eV. In September 2022, spectroscopy on decaying samples determined the excitation energy to be 8.338±0.024 eV. In April 2024, two separate groups finally reported precision laser excitation Th4+ cations doped into ionic crystals (of CaF2 and LiSrAlF6 with additional interstitial F− anions for charge compensation), giving a precise (~1 part per million) measurement of the transition energy.
Sources: en.wikipedia.org
Native GLP-1 is degraded within minutes by dipeptidyl peptidase-4 and neutral endopeptidases. Semaglutide carries a non-natural amino acid at position eight that blocks that cleavage, and a fatty diacid side chain that binds albumin. The result is a much longer duration of action than the native hormone.
The fatty diacid chain associates strongly with serum albumin, which keeps the peptide in circulation and shields it from rapid renal clearance. Bound peptide is released gradually, producing a sustained receptor signal. This mechanism also reduces the peak-to-trough variation seen with shorter-acting analogues.
The balance between peripheral receptor activation and signalling in the central nervous system is not fully resolved. The extent to which slowed gastric emptying accounts for reduced energy intake, compared with direct effects on appetite circuits, is debated. Long-term effects on lean mass and on tissues outside the gut and brain are still under study.
冻融过程中冰晶形成与局部浓度升高会促使肽链发生界面吸附和聚集。聚集不仅降低有效含量，还会改变可见异物与不溶性微粒的计数结果。将溶液分装为单次使用的小体积等份可减少循环次数。