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1.
Yasser H El Hamaky Somaia Tawfeek Dalia F Ibrahim Dalia Maamoun Said Gaber 《Coloration Technology》2007,123(6):365-373
The behaviour of reactive dyes of high reactivity during the printing process of 100% cotton fabrics from an alkaline and acidic printing paste was studied in detail. The printing pastes were stored for different periods of time and then the fabrics were printed. The samples were subjected to two methods of fixation, the first by steaming and the second by thermofixation. The effects of different factors such as alkali and acid concentration, storage time of the printing pastes and method of fixation on the K/S values of the prints were investigated. The fastness properties of the printed areas were also measured to determine the improvement obtained by acidic printing with high-reactivity reactive dyes on cotton fabrics. 相似文献
2.
OBJECTIVE: Our purpose was to study the mechanism by which 17 beta-estradiol modulates contractile activity in isolated rings of omental artery from nonpregnant and pregnant patients. STUDY DESIGN: Rings of omental artery with intact endothelium from nonpregnant and pregnant women were mounted in organ chambers for isometric tension recording. The concentration-relaxation relationship to 17 beta-estradiol (10(-7) mol/L to 3 x 10(-5) mol/L) was studied in rings contracted with 60 mmol/L potassium chloride (in both the absence and the presence of tamoxifen, 10(-6) mol/L). The effect of 17 beta-estradiol (10(-5) mol/L) on the contraction induced by 60 mmol/L potassium chloride and on the concentration-contraction relationships to both norepinephrine (10(-9) mol/L to 10(-5) mol/L) and calcium ion (0.05 mmol/L to 2.5 mmol/L in calcium-free depolarizing solution) were studied in the presence and absence of tamoxifen (10(-6) mol/L). The maximal contraction, negative logarithm of the concentration producing 50% relaxation or 50% contraction to the reference 60 mmol/L potassium chloride contraction, and the area under the curve were calculated. Data analysis was by one-way analysis of variance, Newman-Keuls test, and two-sample tests as appropriate. Probability values less than 0.05 in a two-tailed test were considered statistically significant. RESULTS: 17 beta-Estradiol relaxed omental arteries contracted with 60 mmol/L potassium chloride, and this effect was potentiated by tamoxifen in both groups. Incubation of the omental arteries with 17 beta-estradiol inhibited contractions induced by 60 mmol/L potassium chloride in rings from both groups of patients, and tamoxifen did not antagonize this effect in either group. Rings of omental artery from the nonpregnant patients (expressed as percentage of the reference potassium chloride contraction) showed greater contraction than rings from the pregnant women when exposed to norepinephrine, a statistically significant difference. 17 beta-Estradiol decreased the norepinephrine-induced contraction in omental arteries from nonpregnant but not pregnant women in a statistically significant way. Tamoxifen did not influence the effect of norepinephrine for either group. 17 beta-Estradiol inhibited calcium ion-induced contraction similarly in rings of omental artery from both nonpregnant and pregnant patients. Tamoxifen potentiated estradiol-induced inhibition in arteries from pregnant patients. CONCLUSIONS: 17 beta-Estradiol inhibits norepinephrine-induced contractions in omental arteries from nonpregnant but no pregnant patients. The inhibition of the ter sion developed after exposure to potassium chloride, norepinephrine, and calcium ion is caused by a calcium channel blocking action. 相似文献
3.
Maamoun M. Habbaba Kutlu
. Ülgen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,69(4):405-414
The adsorption of proteins to ion exchangers was investigated by finite bath experiments and by computer simulations using existing rate models. Experimental data were obtained for the binding of bovine serum albumin at different feed concentrations to both cation and anion exchangers. The results were interpreted together with model predictions and the values of the parameters characterizing the mass transfer mechanisms as well as the interaction rates of the adsorbate–adsorbent complex were estimated. The best agreement between theory and experiment throughout the whole period of adsorption process was obtained with a complex model where several steps of the overall mechanism were simultaneously controlling the overall rate. The simplified models, which offer rapid solution requiring less computational power, can be used at low feed concentrations of the proteins where the mechanisms controlling the adsorption rate are less complex. As the interaction rate mechanism and the intraparticle mass transfer mechanism in the adsorbent particles are the same in both finite bath and column adsorption systems, the information presented in this paper can be used to predict the protein adsorption in a column chromatography system. © 1997 SCI. 相似文献
4.
Maamoun Basheer Elias Saad Orly Laskar Ofir Schuster Hagai Rechnitzer Simona Zisman-Rozen David Azoulay Nimer Assy 《International journal of molecular sciences》2021,22(16)
Coronavirus disease (COVID-19) is a contagious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This case report presents a patient who had difficulty eradicating the corona virus due to being treated with Rituximab, which depletes B lymphocyte cells and therefore disables the production of neutralizing antibodies. The combined use of external anti-viral agents like convalescent plasma, IVIG and Remdesivir successfully helped the patient’s immune system to eradicate the virus without B-cell population recovery. In vitro studies showed that convalescent plasma is the main agent that helped in eradicating the virus. 相似文献
5.
O. Esquivel M. E. Treviño H. Saade J. E. Puig E. Mendizábal R. G. López 《Polymer Bulletin》2011,67(2):217-226
The synthesis by semicontinuous heterophase polymerization and the characterization of mesoporous crosslinked polystyrene
particles in the nanometer range (ca. 30 nm) are reported here. The particles have pores between 6 and 8 nm in diameter and
pore volume around 0.40 cm3/g. In spite that the polymerization was not carried out at highly monomer-starved conditions, particles with narrow size
distribution were obtained, which is ascribed to inter-particle hetero-coagulation at latter stages of polymerization, due
to lack of enough surfactant to cover all the particles even before 45% global conversion. 相似文献
6.
This paper addresses the defuzzification of the fuzzy set outputs of fuzzy controllers from a comparison or ranking perspective. This is done by emphasizing the fuzzy controller as a decision-making system. Based on the extensive study and justification of the fuzzy-set comparison criteria that were developed and published elsewhere by the author, a ranking and, thus, a defuzzification index is introduced. This index is shown to overcome the disadvantages of the commonly used defuzzification methods whose attempted justifications based on probabilistic arguments have not been successful. In addition, the proposed index is based on the generalization of the Hurwicz criterion that is usually adopted in decision making under nonprobabilistic uncertainty and it encompasses the pessimistic maximin and the optimistic maximax criteria as special cases 相似文献
7.
Luiz Fernando G. Soares Rogério F. Rodrigues Débora C. Muchaluat Saade 《Multimedia Systems》2000,8(2):118-134
This paper discusses multimedia and hypermedia modeling, authoring and formatting tools, presenting the proposals of the
HyperProp system and comparing them to related work. It also highlights several research challenges that still need to be
addressed. Moreover, it stresses the importance of document logical structuring and considers the use of compositions in order
to represent context relations, synchronization relations, derivation relations and task relations in hypermedia systems.
It discusses temporal and spatial synchronization among multimedia objects and briefly presents the HyperProp graphical authoring
and formatting tools. Integration between the proposed system and the WWW is also addressed. 相似文献
8.
Maamoun HA Soliman AR El Sherif R 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(4):563-567
In the hemodialysis population, the incidence of Staphylococcus aureus colonization has been documented to be as high as 80%; effective prophylaxis of vascular access infection and bacteremia is a worthwhile goal in the management of hemodialysis population. Surveillance of 50 hemodialysis patients for S. aureus‐positive nasal cultures was performed by monthly nasal swabs over a 12‐month period. All patients were performing dialysis using hemodialysis catheters thrice weekly. All positive cultures were treated with a prophylactic antibiotic regimen. Thirty‐one patients (62%) had one or more positive cultures. The surveillance period was longer in the S. aureus nasal carriers (p < 0.01). The frequency of positive cultures correlated with the duration of surveillance (p < 0.05). The incidence of S. aureus bacteremia was greater in patients with three or more positive cultures (p < 0.05). This study suggests that continuous surveillance for S. aureus nasal colonization is essential to properly identify all hemodialysis patients using catheters at risk of developing S. aureus bacteremias. 相似文献
9.
I. A. Facundo M. J. Soria M. G. Rosales L. E. Elizalde R. Díaz de León H. Saade R. G. López 《Polymer Bulletin》2011,67(6):985-995
Thermosensitive core–shell nanoparticles were synthesized by semicontinuous heterophase polymerization of styrene, followed
by a seeded polymerization for forming a shell of poly(N-isopropyl acrylamide) (PNIPAM). Nanoparticles characterization by scanning transmission electronic microscopy showed core–shell
morphology with average particle diameters around 40 nm. An inverse dependence of the particle size with temperature in the
range 20–55 °C was identified by quasielastic light scattering measurements. As was expected for core–shell particles with
PNIPAM as the shell, a volume phase transition near 32 °C was detected. In spite of thermosensitive properties of core–shell
nanoparticles synthesized here, the volume percentage loss values were not so high, probably due to their relatively low content
of PNIPAM. 相似文献
10.
Ageing constitutes a risk factor for magnesium deficit. Primary magnesium deficit originates from two etiological mechanisms: deficiency and depletion. Primary magnesium deficiency is due to insufficient magnesium intake. Dietary amounts of magnesium are marginal in the whole population whatever the age. Nutritional deficiencies are more pronounced in institutionalized than in free-living ageing groups. Primary magnesium depletion is due to dysregulation of factors controlling magnesium status: intestinal magnesium hypoabsorption, reduced magnesium bone uptake and mobilisation, sometimes urinary leakage, hyperadrenoglucocorticism by decreased adaptability to stress, insulin-resistance and adrenergic hyporeceptivity. Secondary magnesium deficit in ageing largely results from various pathologies and treatments common to elderly persons: i.e. non insulin dependent diabetes mellitus and use of hypermagnesuric diuretics. Magnesium deficit may participate in the clinical pattern of ageing: mainly neuromuscular, cardiovascular and renal symptomatologies. The consequences of hyperadrenoglucocorticism--whose non response to dexamethasone suppression test appears the simplest marker--may concern immunosuppression, muscle atrophy, centralization of fat mass, osteoporosis, hyperglycemia, hyperlipidemia, atherosclerosis, disturbances in mood and mental performances through accelerated hippocampal ageing particularly. Treatment of magnesium deficiency requires simple oral physiological magnesium supplementation. Treatment of the different types of magnesium depletion leads to a more or less specific control of pathophysiological disturbances of the required magnesium substrate. Open and double blind studies on the effects of the treatments of magnesium deficiency and of magnesium depletions in geriatic populations are too scarce. Further study is necessary to assess the accurate place of magnesium deficit in the physiopathology of ageing. 相似文献