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排序方式: 共有3227条查询结果,搜索用时 15 毫秒
61.
Zahra Elyasi Javad Safaei Ghomi Gholam Reza Najafi Mohammad Reza Zand Monfared 《RSC advances》2020,10(72):44159
Although poly (ionic liquids) (PILs) have attracted great research interest owing to their various applications, the performance of nanoporous PILs has been rarely developed in the catalysis field. To this end, a micro–mesoporous PIL with acid–base bifunctional active sites was designed and fabricated by two different polymerization protocols including hydrothermal and classical precipitation polymerization in this paper. Based on our observations, hydrothermal conditions (high temperature and pressure) enabled the proposed sonocatalyst to possess a great porous structure with a high specific surface area (SBET: 315 m2 g−1) and thermal stability (around 450 °C for 45% weight loss) through strengthening cross-linking. In a comparative study, the preferred nanoporous PIL was selected and utilized as the sonocatalyst in a multicomponent reaction of isatins, primary amines, and thioglycolic acid. In the following, a variety of new and known pharmaceutical spiro-4-thiazolidinone derivatives were synthesized at room temperature and obtained excellent yields (>90%) within short reaction times (4–12 min) owing to the substantial synergistic effect between ultrasound irradiation and magnetically separable catalyst.Sustainable synthesize of a new mesoporous poly (ionic liquid) as acid–base bifunctional catalyst for environmental being preparation of monospiro derivatives has been developed. 相似文献
62.
Lars Burdorf Christopher T. Laird Donald G. Harris Margaret R. Connolly Zahra Habibabady Emily Redding Natalie A. O'Neill Arielle Cimeno Dawn Parsell Carol Phelps David Ayares Agnes M. Azimzadeh Richard N. Pierson 《American journal of transplantation》2022,22(1):28-45
Galactosyl transferase knock-out pig lungs fail rapidly in baboons. Based on previously identified lung xenograft injury mechanisms, additional expression of human complement and coagulation pathway regulatory proteins, anti-inflammatory enzymes and self-recognition receptors, and knock-down of the β4Gal xenoantigen were tested in various combinations. Transient life-supporting GalTKO.hCD46 lung function was consistently observed in association with either hEPCR (n = 15), hTBM (n = 4), or hEPCR.hTFPI (n = 11), but the loss of vascular barrier function in the xenograft and systemic inflammation in the recipient typically occurred within 24 h. Co-expression of hEPCR and hTBM (n = 11) and additionally blocking multiple pro-inflammatory innate and adaptive immune mechanisms was more consistently associated with survival >1 day, with one recipient surviving for 31 days. Combining targeted genetic modifications to the lung xenograft with selective innate and adaptive immune suppression enables prolonged initial life-supporting lung function and extends lung xenograft recipient survival, and illustrates residual barriers and candidate treatment strategies that may enable the clinical application of other organ xenografts. 相似文献
63.
Hossein?Yazdekhasti Zahra?Rajabi Soraya?Parvari Mehdi?AbbasiEmail authorView authors OrcID profile 《Journal of ovarian research》2016,9(1):68
Although existence of ovarian stem cells (OSCs) in mammalian postnatal ovary is still under controversy, however, it has been almost accepted that OSCs are contributing actively to folliculogenesis and neo-oogenesis. Recently, various methods with different efficacies have been employed for OSCs isolation from ovarian tissue, which these methods could be chosen depends on aim of isolation and accessible equipments and materials in lab. Although isolated OSCs from different methods have various traits and characterizations, which might become from their different nature and origin, however these stem cells are promising source for woman infertility treatment or source of energy for women with a history of repeat IVF failure in near future. This review has brought together and summarized currently used protocols for isolation and propagation of OSCs in vitro. 相似文献
64.
Movahedi M Entezari N Pourpak Z Mamishi S Chavoshzadeh Z Gharagozlou M Mir-Saeeid-Ghazi B Fazlollahi MR Zandieh F Bemanian MH Farhoudi A Aghamohammadi A 《Journal of clinical immunology》2007,27(3):302-307
Leukocyte adhesion deficiency type I (LAD I) is a rare, inherited, autosomal recessive, immunodeficiency disease caused by
the combined loss of expression on the surface of leukocytes of the leukocyte integrins. We describe the clinical and laboratory
findings for 15 patients with LAD I.
The range of patients’ ages was from 10 month to 14 years (median 4 years) and 93.3% of their parents had consanguineous marriages.
The most commonly occurred manifestations were: recurrent infections (93.3%), poor wound healing (86%), oral ulcers (86%),
and skin abscesses (80%). The most specific laboratory findings were defect in CD18 in all of 15 patients.
The most common symptoms in these patients are poor wound healing and oral ulcer, so, the clinical physicians should pay special
attention to these symptoms. Furthermore, because of considerable rate of consanguineous marriages in parents of LAD patients,
we suggested more genetic studies on this disease and genetic consultation for these families.
An erratum to this article can be found at 相似文献
65.
The brain is unique among organs in many respects, including its mechanisms of lipid synthesis and energy production. The nervous system-specific metabolite N-acetylaspartate (NAA), which is synthesized from aspartate and acetyl-coenzyme A in neurons, appears to be a key link in these distinct biochemical features of CNS metabolism. During early postnatal central nervous system (CNS) development, the expression of lipogenic enzymes in oligodendrocytes, including the NAA-degrading enzyme aspartoacylase (ASPA), is increased along with increased NAA production in neurons. NAA is transported from neurons to the cytoplasm of oligodendrocytes, where ASPA cleaves the acetate moiety for use in fatty acid and steroid synthesis. The fatty acids and steroids produced then go on to be used as building blocks for myelin lipid synthesis. Mutations in the gene for ASPA result in the fatal leukodystrophy Canavan disease, for which there is currently no effective treatment. Once postnatal myelination is completed, NAA may continue to be involved in myelin lipid turnover in adults, but it also appears to adopt other roles, including a bioenergetic role in neuronal mitochondria. NAA and ATP metabolism appear to be linked indirectly, whereby acetylation of aspartate may facilitate its removal from neuronal mitochondria, thus favoring conversion of glutamate to alpha ketoglutarate which can enter the tricarboxylic acid cycle for energy production. In its role as a mechanism for enhancing mitochondrial energy production from glutamate, NAA is in a key position to act as a magnetic resonance spectroscopy marker for neuronal health, viability and number. Evidence suggests that NAA is a direct precursor for the enzymatic synthesis of the neuron specific dipeptide N-acetylaspartylglutamate, the most concentrated neuropeptide in the human brain. Other proposed roles for NAA include neuronal osmoregulation and axon-glial signaling. We propose that NAA may also be involved in brain nitrogen balance. Further research will be required to more fully understand the biochemical functions served by NAA in CNS development and activity, and additional functions are likely to be discovered. 相似文献
66.
Khani Tahereh Alamzadeh Zahra Sarikhani Abolfazl Mousavi Mahdie Mirrahimi Mehri Tabei Mousa Irajirad Rasoul Abed Ziaeddin Beik Jaber 《Lasers in medical science》2022,37(5):2387-2395
Lasers in Medical Science - The combination of multiple therapeutic and diagnostic functions is fast becoming a key feature in the area of clinical oncology. The advent of nanotechnology promises... 相似文献
67.
68.
Mazdak Hamid Tolou_Ghamari Zahra Gholampour Mehdi 《International urology and nephrology》2020,52(7):1255-1260
International Urology and Nephrology - Free radicals play an important role in the different complex course of carcinogenesis. Higher concentrations of reactive oxygen species are highly associated... 相似文献
69.
70.
Iman Karimzadeh Hossein Khalili Simin Dashti-Khavidaki Ramezanali Sharifian Alireza Abdollahi Mehrdad Hasibi Zahra Khazaeipour Shadi Farsaei 《European journal of clinical pharmacology》2014,70(4):399-408