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41.
Rashid A. Zeineh George Kyriakidis A. Rashid Bhatti 《Applied biochemistry and biotechnology》1986,13(2):111-117
Virion polypeptides (35 S), methionine-labeled and purified by CsCl gradient centrifugation, were separated by SDS-gel electrophoresis. Analysis of their band pattern was performed by scanning the images of the SDS-gels shown on a 35-mm slide. The densitometric tracings revealed the presence of 17 protein bands, although only 15 of them were visible to the naked eye. The high sensitivity and resolving capacities of the soft-laser scanning densitometer enabled us to detect trace amounts of protein bands separated in SDS-gels and to obtain a resolution compatible to that of electrophoresis. Fourfold electronic amplification of the densitometric tracings, produced by a computer, generated new information regarding the pattern of the electrophoregram. The facility to amplify peaks of importance is particularly advantageous when faint or overlapping protein bands revealed on a gel are assessed. 相似文献
42.
Cheng X Liu YS Irimia D Demirci U Yang L Zamir L Rodríguez WR Toner M Bashir R 《Lab on a chip》2007,7(6):746-755
Cell-based microfluidic devices have attracted interest for a wide range of applications. While optical cell counting and flow cytometry-type devices have been reported extensively, sensitive and efficient non-optical methods to detect and quantify cells attached over large surface areas within microdevices are generally lacking. We describe an electrical method for counting cells based on the measurement of changes in conductivity of the surrounding medium due to ions released from surface-immobilized cells within a microfluidic channel. Immobilized cells are lysed using a low conductivity, hypotonic media and the resulting change in impedance is measured using surface patterned electrodes to detect and quantify the number of cells. We found that the bulk solution conductance increases linearly with the number of isolated cells contributing to solution ion concentration. The method of cell lysate impedance spectroscopy is sensitive enough to detect 20 cells microL(-1), and offers a simple and efficient method for detecting and enumerating cells within microfluidic devices for many applications including measurement of CD4 cell counts in HIV patients in resource-limited settings. To our knowledge, this is the most sensitive approach using non-optical setups to enumerate immobilized cells. The microfluidic device, capable of isolating specific cell types from a complex bio-fluidic and quantifying cell number, can serve as a single use cartridge for a hand-held instrument to provide simple, fast and affordable cell counting in point-of-care settings. 相似文献
43.
An electrolytic device for decomposition of water has been developed which readily gives hydrogen and oxygen for isotopic measurement with a mass spectrometer. A 20-mul sample can be decomposed quantitatively in 10 min with good reproducibility. The results produced are comparable with those obtained by reduction with uranium. 相似文献
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45.
Samina Rubnawaz Waqas Khan Kayani Nosheen Akhtar Rashid Mahmood Asif Khan Mohammad K. Okla Saud A. Alamri Ibrahim A. Alaraidh Yasmeen A. Alwasel Bushra Mirza 《Molecules (Basel, Switzerland)》2021,26(16)
Ajuga bracteosa Wall. ex Benth. is an endangered medicinal herb traditionally used against different ailments. The present study aimed to create new insight into the fundamental mechanisms of genetic transformation and the biological activities of this plant. We transformed the A. bracteosa plant with rol genes of Agrobacterium rhizogenes and raised the regenerants from the hairy roots. These transgenic regenerants were screened for in vitro antioxidant activities, a range of in vivo assays, elemental analysis, polyphenol content, and different phytochemicals found through HPLC. Among 18 polyphenolic standards, kaempferol was most abundant in all transgenic lines. Furthermore, transgenic line 3 (ABRL3) showed maximum phenolics and flavonoids content among all tested plant extracts. ABRL3 also demonstrated the highest total antioxidant capacity (8.16 ± 1 μg AAE/mg), total reducing power, (6.60 ± 1.17 μg AAE/mg), DPPH activity (IC50 = 59.5 ± 0.8 μg/mL), hydroxyl ion scavenging (IC50 = 122.5 ± 0.90 μg/mL), and iron-chelating power (IC50 = 154.8 ± 2 μg/mL). Moreover, transformed plant extracts produced significant analgesic, anti-inflammatory, anticoagulant, and antidepressant activities in BALB/c mice models. In conclusion, transgenic regenerants of A. bracteosa pose better antioxidant and pharmacological properties under the effect of rol genes as compared to wild-type plants. 相似文献
46.
Let (X,?) be a partially ordered set and d be a complete metric on X. Let F,G be two set-valued mappings on X. We obtained sufficient conditions for the existence of common fixed point of F and G satisfying an implicit relation in partially ordered set X. 相似文献
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48.
Dengue fever is one of the most dangerous vector‐borne diseases in the world in terms of death and economic cost. Hence, the modeling of dengue fever is of great significance to understand the dynamics of dengue. In this paper, we extend dengue disease transmission models by including transmit vaccinated class, in which a portion of recovered individual loses immunity and moves to the susceptibles with limited immunity and hence a less transmission probability. We obtain the threshold dynamics governed by the basic reproduction number R0; it is shown that the disease‐free equilibrium is locally asymptotically stable if R0 ≤ 1, and the system is uniformly persistence if R0 > 1. We do sensitivity analysis in order to identify the key factors that greatly affect the dengue infection, and the partial rank correlation coefficient (PRCC) values for R0 shows that the bitting rate is the most effective in lowering dengue new infections, and moreover, control of mosquito size plays an essential role in reducing equilibrium level of dengue infection. Hence, the public are highly suggested to control population size of mosquitoes and to use mosquito nets. By formulating the control objective, associated with the low infection and costs, we propose an optimal control question. By the application of optimal control theory, we analyze the existence of optimal control and obtain necessary conditions for optimal controls. Numerical simulations are carried out to show the effectiveness of control strategies; these simulations recommended that control measures such as protection from mosquito bites and mosquito eradication strategies effectively control and eradicate the dengue infections during the whole epidemic. 相似文献
49.
The index of a graded ideal measures the number of linear steps in the graded minimal free resolution of the ideal. In this paper, we study the index of powers and squarefree powers of edge ideals. Our results indicate that the index as a function of the power of an edge ideal I is strictly increasing if I is linearly presented. Examples show that this needs not to be the case for monomial ideals generated in degree greater than two. 相似文献
50.
Mohammed Harunor Rashid 《计算数学(英文版)》2022,40(1):44-69
In the present paper,we study the restricted inexact Newton-type method for solving the generalized equation 0∈f(x)+F(x),where X and Y are Banach spaces,f:X→Y is a Frechet differentiable function and F:X■Y is a set-valued mapping with closed graph.We establish the convergence criteria of the restricted inexact Newton-type method,which guarantees the existence of any sequence generated by this method and show this generated sequence is convergent linearly and quadratically according to the particular assumptions on the Frechet derivative of f.Indeed,we obtain semilocal and local convergence results of restricted inexact Newton-type method for solving the above generalized equation when the Frechet derivative of f is continuous and Lipschitz continuous as well as f+F is metrically regular.An application of this method to variational inequality is given.In addition,a numerical experiment is given which illustrates the theoretical result. 相似文献