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1.
2.
Acetyl LDL (modified low-density lipoprotein), which is thought to be taken up through scavenger receptor A (SR-A), rapidly induced the appearance of phosphotyrosine proteins in monocytic THP-1-derived macrophages in vitro. The two alternative forms of Lyn (p53 and p56) were found to be tyrosine-phosphorylated within 30 s after the stimulation with acetyl LDL. The catalytic activity of Lyn measured by an in vitro kinase assay had also increased in acetyl LDL-stimulated THP-1-derived macrophages. Furthermore, Lyn could be co-immunoprecipitated with SR-A from the cell lysate. These observations suggest a functional and possible physical association of SR-A with Lyn in THP-1-derived macrophages, and also imply a possible involvement of Lyn in SR-A signal transduction. 相似文献
3.
Creation of a dynamic levator aponeurosis fold or double eye adds to the beauty of the East Asian. The eyes are larger and less puffy, and the eyelashes appear longer and curve up and out instead of down. The distance from the ciliary border to the eyebrow is decreased and more in proportion. The Mongolian trait is preserved. 相似文献
4.
Pro-opiomelanocortin (POMC) is a polyhormone precursor produced predominantly in the pars distalis and pars intermedia of the pituitary gland where it undergoes tissue specific processing to produce a whole array of peptides. We have shown previously that peptides derived from the N-terminal region of POMC are involved in adrenal growth in rats. Using specific two site immunoradiometric assays we have found that the plasma of 17 week old fetal sheep contain a 50 fold excess of pro-gamma-MSH over ACTH. As term approached, the levels of pro-gamma-MSH fell and ACTH rose with evidence of fragmentation of pro-gamma-MSH, suggesting that these peptides act in concert in the development of the fetal adrenal cortex and also provide the necessary drive to bring about parturition. In an attempt to explore the pathophysiology of adrenal function we have cloned human POMC cDNA which led to the discovery of a 9bp addition/deletion mutation in the C-terminus of gamma 3-MSH between positions 67-73. Chinese hamster ovary cells (CHO) cells stably transfected with constructs containing the variant POMC cDNAs have shown a degree of partial processing. Work is currently underway to further investigate the effects of these mutations on the processing by the prohormone converting enzymes PC1 and PC2. 相似文献
5.
Pori Maja Arčon Iztok Dasireddy Venkata D. B. C. Likozar Blaž Orel Zorica Crnjak Marinšek Marjan 《Catalysis Letters》2021,151(11):3114-3134
Catalysis Letters - Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature... 相似文献
6.
Sergii Sinelnikov Luydmila Orel Larisa Kobrina Valentyna Boiko Sergii Riabov Volodymir Shtompel Olga Povnitsa Svetlana Zagorodnya 《应用聚合物科学杂志》2021,138(23):50554
Polymer cross-linked matrices based on polyacrylamide (PAA) and β-cyclodextrin-pseudorotaxane have been designed. The structure and properties of the objects synthesized were confirmed and studied by a series of methods, involving ultraviolet-, Fourier transform infrared-spectroscopy, thermal mass spectrometry, DSC, X-ray diffraction analysis (WAXS and SAXS). Desorption kinetics (especially significant slowing of desorption process) of some drugs, like metoprolol succinate and loratadine from obtained polymer matrices is shown to be optimal with 10 wt% β-CD-pseudorotaxane in their structure. 相似文献
7.
Microstructural development during transient liquid-phase bonding of cast polycrystalline near-stoichiometric NiAl (B2 compound, -phase) was investigated using cross-sectional transmission electron microscopy. Bonds made using Ni-4.5 wt % Si-3.2 wt % B (AWS designation BNi-3) interlayers in the form of melt-spun foils were studied. Microstructural changes in the joint region and surrounding substrates were examined as a function of holding time at temperatures of 1065 and 1150°C. The transformation of the substrate -phase to L10-type martensite due to aluminium transfer to the joint has been discussed, and the formation of L12 type ( structure) layers at the joint-substrate interfaces considered. The nature of the isothermal solidification process has also been discussed and the changes, with holding time at the bonding temperature, in the character of the residual eutectic examined. The formation of M23X6-type borides within both the joint and surrounding substrates was also considered. 相似文献
8.
This article looks at the current working profile of blast furnaces at the Krivorozhstal’ combine. The profiles were formed during a period in which the operation of the furnaces was not forced, the supply of raw materials was inconsistent, and furnace output was irregular. The results of studies show a need for closer monitoring of the cooling system and the parameters of the profile of furnaces in the period before a scheduled maintenance. Timely action needs to be taken to eliminate problems in furnace operation caused by the presence of thick slag crusts. It is shown that the variable slag-formation conditions about the furnace circumference are due mainly to factors that affect the smelting operation from below — nonuniform blast delivery and a nonuniform distribution of the blast among the tuyeres, as well as local differences in drainage and the movement of coke in the hearth. These differences depend on the location of the iron notches. It is noted that the aggressiveness of alkalis and zinc in blast-furnace shafts has increased. An efficient furnace profile can be maintained by limiting the entry of aggressive compounds into the furnace and washing its interior to remove such compounds from the circulation loop. 相似文献
9.
V. V. Chernyuk B. S. Pitsishin V. I. Orel V. M. Zhuk 《Journal of Engineering Physics and Thermophysics》2002,75(4):910-919
Data of an experimental investigation of the hydraulic resistance of the abrupt contractions and expansions of round pipes to the turbulent flow of polyacrylamide aqueous solutions are presented. An increase and a decrease in the head loss have been revealed. An explanation of the results obtained is given. 相似文献
10.
LL Dever SM Smith D Dejesus M Masurekar D Patel ZC Kaminski WG Johanson 《Canadian Metallurgical Quarterly》1996,2(4):407-413
OBJECTIVE: Previous studies of surgical treatment for acromegaly have used varied criteria for 'cure', but elevated GH levels are considered to be associated with continuing disease activity. We wished to analyse the results of transsphenoidal pituitary surgery for acromegaly and assess the longer-term outcome for patients not offered further treatment when post-operative levels of GH < 5 mU/l were achieved. DESIGN: We studied a retrospective group of patients who underwent transsphenoidal surgery for acromegaly at St Bartholomew's Hospital between 1985 and 1993. PATIENTS: One hundred consecutive patients (53 male, mean age 46 years, range 18-68 years) undergoing transsphenoidal surgery for acromegaly were assessed. The patients were followed for a mean of 3.8 years (range 0.5-8 years) after operation. MEASUREMENTS: GH levels are represented as a mean value from a four-point day curve taken at 0830, 1300, 1700 and 1900 h. ACTH reserve was assessed basally and, if this was normal, with the insulin tolerance or glucagon tests. TSH, T4, PRL, LH, FSH, testosterone or oestradiol and plasma and urine osmolality were also measured. RESULTS: Post-operatively, 42% of patients achieved a mean GH level of < 5 mU/l. The success of surgery was related to the preoperative GH level; 65% of the patients with preoperative GH levels < 20 mU/l but only 18% of the patients with GH levels > 100 mU/l achieved post-operative GH values < 5 mU/l. In addition, tumour size influenced the outcome of surgery with 61% of patients with a microadenoma but only 23% of patients with a macroadenoma achieving post-operative GH levels of < 5 mU/l. Of the 42 patients considered in remission post-operatively (mean GH < 5 mU/l), 32 were available for long-term follow-up and were not offered any further treatment: only one of these has shown evidence of mild biochemical recurrence after a mean follow-up of 3.8 years (range 0.5-8). There were no peri-operative deaths. Two patients required surgical repair for CSF leaks and there were eight documented cases of meningitis. Permanent diabetes insipidus was noted in eight patients post-operatively. New anterior pituitary deficiency occurred in 21% of patients following surgery; 73% had unaltered pituitary function and in 6% recovery of partial hypopituitarism was noted. CONCLUSIONS: The stated outcome of surgery depends on the criteria adopted. Safe GH levels (mean levels < 5 mU/l) can be achieved in 42% of an unselected series of patients with acromegaly and if the tumour is a microadenoma this figure rises to 61%. Based on the current evidence it is safe not to offer further treatment to those patients in whom post-operative GH < 5 mU/l are achieved. 相似文献