The absolute configuration of mitomycin C was determined?by X-ray single crystal diffraction?(CuKα), and a new?crystalline?dihydrate of mitomycin C had been prepared. The?experiment?result?provides?a definitive answe...The absolute configuration of mitomycin C was determined?by X-ray single crystal diffraction?(CuKα), and a new?crystalline?dihydrate of mitomycin C had been prepared. The?experiment?result?provides?a definitive answer?to the real absolute configuration of mitomycin C and may put an end to the dispute?that baffles?researchers for decades.?At the same time, some contentious structures?about the mitomycin C in?American Pharmacopoeia?USP36-NF31,?Chinese pharmacopoeia?2015?edtion?and numbers of?literatures are marked. The absolute configuration?is?also verified?by?1D (1H?and?13C) and 2D (HSQC, HMBC,?1H-1H?COSY?and?NOESY) NMR studies?indirectly. Powder X-ray diffraction (PXRD) pattern of the?mitomycin C dihydrate?is similar to that calculated for?it, which?suggests that the purity?of?sample?is excellent.展开更多
Gastrointestinal cancers, including esophageal cancer, gastric cancer, liver cancer, pancreatic cancer, colorectal cancer, are serious threats to people's health, and traditional therapeutic drugs have limited eff...Gastrointestinal cancers, including esophageal cancer, gastric cancer, liver cancer, pancreatic cancer, colorectal cancer, are serious threats to people's health, and traditional therapeutic drugs have limited effect on them. Signaling pathway related to mammalian target of rapamycin (mTOR) plays a very important role either in the germination or development of multiple gastrointestinal cancers. Inhibiting mTOR can effectively impede the development of tumor and improve the sensitivity of tumor to radiotherapy or chemotherapy. The research on the application of mTOR inhibitors in gastrointestinal cancers increases with years. A lot of operational schemes independent or combined with others are being explored, some of which are worthy of attention. This paper summarizes the data of all published clinical trials and reviews the clinical application of mTOR inhibitors in the treatment of gastrointestinal cancers in recent years.展开更多
Type 2 Diabetes Mellitus (T2DM) is a systemic metabolic disorder with complex pathogenesis. In recent years, a variety of new T2DM drugs have emerged, such as sodium-dependent glucose transporters 2 (SGLT-2) inhibitor...Type 2 Diabetes Mellitus (T2DM) is a systemic metabolic disorder with complex pathogenesis. In recent years, a variety of new T2DM drugs have emerged, such as sodium-dependent glucose transporters 2 (SGLT-2) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors. As traditional medicines, insulin also has developed kinds of formulations such as quick-acting or premixed insulin. In addition, new treatment schedules combining multiple drugs are also fully explored. The efficacy, the administration, the mechanism, the safety and the price of these drugs are all different, providing patients with multiple options. This paper reviews the main types of type 2 diabetes drugs on the market and describes the mechanism of action. The representative type 2 diabetes treatment drugs are listed, and the advantages and disadvantages of these representative drugs are preliminarily evaluated. This information is reviewed to help doctors with clinical medication.展开更多
Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particul...Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particular consideration on shell and pair effects,the decay energy Q as well as the nucleon numbers(Z,N).Although the formula has relatively few parameters,it reproduces the experimentalβ^--decay half-lives of neutron-rich nuclei very well.The predicted half-lives for the r-process relevant nuclei obtained with the current formula serve as reliable input in the r-process model calculations.展开更多
文摘The absolute configuration of mitomycin C was determined?by X-ray single crystal diffraction?(CuKα), and a new?crystalline?dihydrate of mitomycin C had been prepared. The?experiment?result?provides?a definitive answer?to the real absolute configuration of mitomycin C and may put an end to the dispute?that baffles?researchers for decades.?At the same time, some contentious structures?about the mitomycin C in?American Pharmacopoeia?USP36-NF31,?Chinese pharmacopoeia?2015?edtion?and numbers of?literatures are marked. The absolute configuration?is?also verified?by?1D (1H?and?13C) and 2D (HSQC, HMBC,?1H-1H?COSY?and?NOESY) NMR studies?indirectly. Powder X-ray diffraction (PXRD) pattern of the?mitomycin C dihydrate?is similar to that calculated for?it, which?suggests that the purity?of?sample?is excellent.
文摘Gastrointestinal cancers, including esophageal cancer, gastric cancer, liver cancer, pancreatic cancer, colorectal cancer, are serious threats to people's health, and traditional therapeutic drugs have limited effect on them. Signaling pathway related to mammalian target of rapamycin (mTOR) plays a very important role either in the germination or development of multiple gastrointestinal cancers. Inhibiting mTOR can effectively impede the development of tumor and improve the sensitivity of tumor to radiotherapy or chemotherapy. The research on the application of mTOR inhibitors in gastrointestinal cancers increases with years. A lot of operational schemes independent or combined with others are being explored, some of which are worthy of attention. This paper summarizes the data of all published clinical trials and reviews the clinical application of mTOR inhibitors in the treatment of gastrointestinal cancers in recent years.
文摘Type 2 Diabetes Mellitus (T2DM) is a systemic metabolic disorder with complex pathogenesis. In recent years, a variety of new T2DM drugs have emerged, such as sodium-dependent glucose transporters 2 (SGLT-2) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors. As traditional medicines, insulin also has developed kinds of formulations such as quick-acting or premixed insulin. In addition, new treatment schedules combining multiple drugs are also fully explored. The efficacy, the administration, the mechanism, the safety and the price of these drugs are all different, providing patients with multiple options. This paper reviews the main types of type 2 diabetes drugs on the market and describes the mechanism of action. The representative type 2 diabetes treatment drugs are listed, and the advantages and disadvantages of these representative drugs are preliminarily evaluated. This information is reviewed to help doctors with clinical medication.
基金supported by the National Natural Science Foundation of China(Grant Nos.11490563 and 11375269)the National Basic Research Program of China(Grant No.2013CB834406)the National Key Research and Development Program of China(Grant No.2016YFA0400502)
文摘Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particular consideration on shell and pair effects,the decay energy Q as well as the nucleon numbers(Z,N).Although the formula has relatively few parameters,it reproduces the experimentalβ^--decay half-lives of neutron-rich nuclei very well.The predicted half-lives for the r-process relevant nuclei obtained with the current formula serve as reliable input in the r-process model calculations.
