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81.
Amphiphilic block copolymers have been the subject of great scientific interests due to their applications in various fields including nano drug delivery. Three amphiphilic block copolymers based on poly(ε-caprolactone) as a hydrophobic segment and methoxy poly(ethylene oxide) ( as a hydrophilic part were synthesized by the ring-opening polymerization of ε-caprolactone using MeO-PEO5K as macroinitiator by varying initial feed ratios. The synthesized polymers were further explored for their drug delivery potential using clotrimazole as model hydrophobic drug. Drug-loaded micelles were characterized for shape, size, drug encapsulation efficiency, in vitro release, and thermal stability using atomic force microscope, zetasizer, UV–visible spectrophotometry, FTIR, differential scanning calorimetry, and thermogravimetric analysis. Clotrimazole loaded in micelles were also investigated for its antifungal activity through an in vitro assay and scanning electron microscopy. The antifungal activity of drug increased significantly by delivering through polymeric micelles. Current study provides insight into different factors that can be maneuvered to achieve a variety of desired properties of micelles for improved therapeutic efficacy of drugs like clotrimazole. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47769.  相似文献   
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83.
The autonomic nervous system plays a significant role in liver physiology and pathology. The aim of the present study was to investigate peptidergic nerve fibres in the liver of patients with malignant gastrointestinal tumors that are not metastasizing in this organ. Using light and electron microscopic immunohistochemistry, somatostatin (SOM)-, neuropeptide Y (NPY)-, substance P (SP)- and calcitonin gene-related peptide (CGRP)-immunoreactive (IR) nerve fibres (NF) were detected in the portal tract and perisinusoidally. Histologically, the liver showed dilated sinusoids, filled with lymphoid cells, and scarcely marked perisinusoidal fibrosis. Neuropeptide-IR NF were found in close contact with hepatic sinusoids. Numerous IR varicosities were detected in the sinusoidal wall. We discuss the origin and role of these NF in the liver. Probable quantitative changes in peptidergic NF ensue the inflammatory reaction in sinusoids in malignant gastrointestinal tumors. This could also reflect the increased exposure of the liver to toxic substances in the portal blood flow.  相似文献   
84.
A novel LST architecture that outperforms the performance of V-BLAST, in the presence of channel estimation errors at the receiver, is proposed. Multiplexing gain is traded-off by transmitting known symbols from one of the transmit antennas, which allows an enhancement in diversity due to an improved interference suppression.  相似文献   
85.
The purpose of this study was to determine through noninvasive arm ergometry and radionuclide tomographic imaging the presence of latent coronary heart disease (CHD) in subjects with paraplegia. Assessment of CHD in spinal cord injury, using these methods, has not been addressed previously. Twenty asymptomatic subjects with paraplegia performed arm ergometry exercise stress testing with thallium-201 single photon emission computerized tomography (SPECT) or planar myocardial imaging studies. All subjects had normal resting electrocardiograms (ECG). Only five subjects had ECG evidence of ischemia on exercise testing, whereas 13 subjects, including the five subjects with ECG positive stress tests, had scintigraphic evidence of ischemia. Thus, eight subjects would have been undiagnosed for CHD without thallium-201 SPECT imaging. These individuals had multiple risk factors for CHD and, except for age, were without a statistically significant difference between the groups with positive or negative thallium stress imaging studies. Arm ergometry stress thallium imaging shows a high prevalence of ischemia in subjects with paraplegia.  相似文献   
86.
Monoclonal antibodies and flow cytometry were used to detect the expression of c-myc and c-myb in the bone marrow (BM) and peripheral blood (PB) cells of patients with acute myelogenous leukemia (AML). The expression of neither gene was correlated with the percent blast cells in the BM or PB nor was there a correlation between c-myc and c-myb expression. A wide range of expression of each gene was found within each FAB type of AML. Patients who had a high proportion of leukemia cells expressing c-myb were less likely to respond to remission induction therapy than patients in whom a low proportion of cells expressed c-myb. This association appears to reflect an inverse relationship between the proportion of cells expressing c-myb and the sensitivity of leukemia cells to the killing effects of chemotherapy in vivo. Treatment outcome was unrelated to c-myc expression.  相似文献   
87.
Design of a low-cost fiber–wireless communication architecture is desirable by network operators. Therefore, we demonstrate the transmission of \(2 \times 2\) MIMO spatial streams, each having 2 Gbps DPSK signal to two different radio access units (RAUs) in a distributed antenna system architecture. The proposed architecture employs mode group division multiplexing in combination with wavelength division multiplexing to transport RF DPSK signals centered at 10 GHz. The RF signals are used to modulate optical carriers that are centered at 1300 nm and transmitted toward the RAUs over perfluorinated graded-index plastic optical fiber. Heterodyne detection is performed at the RAUs to transmit mm-wave signals at 60 GHz to the end users. Furthermore, wireline access is also achieved at each RAU to support simplex services. A cost-efficient multiple wavelength source is generated from a single laser by employing a dual-drive Mach–Zehnder modulator. An increase in multiplexing gain is achieved using the two LP modes, LP01 and LP11, of each generated wavelength. The proposed architecture gives acceptable BER results for practical implementation.  相似文献   
88.
This paper focus on providing a secure and trustworthy solution for virtual machine (VM) migration within an existing cloud provider domain, and/or to the other federating cloud providers. The infrastructure-as-a-service (IaaS) cloud service model is mainly addressed to extend and complement the previous Trusted Computing techniques for secure VM launch and VM migration case. The VM migration solution proposed in this paper uses a Trust_Token based to guarantee that the user VMs can only be migrated and hosted on a trustworthy and/or compliant cloud platforms. The possibility to also check the compliance of the cloud platforms with the pre-defined baseline configurations makes our solution compatible with an existing widely accepted standards-based, security-focused cloud frameworks like FedRAMP. Our proposed solution can be used for both inter- and intra-cloud VM migrations. Different from previous schemes, our solution is not dependent on an active (on-line) trusted third party; that is, the trusted third party only performs the platform certification and is not involved in the actual VM migration process. We use the Tamarin solver to realize a formal security analysis of the proposed migration protocol and show that our protocol is safe under the Dolev-Yao intruder model. Finally, we show how our proposed mechanisms fulfill major security and trust requirements for secure VM migration in cloud environments.  相似文献   
89.
Raza  Syed M.  Thorat  Pankaj  Challa  Rajesh  Jeon  Seil  Choo  Hyunseung 《Wireless Networks》2020,26(1):603-620
Wireless Networks - The soaring number of mobile devices and their demands for enhanced services have forced operators to adopt locally software defined and globally distributed multi-domain...  相似文献   
90.
Over the past few years, taxanes have emerged as a new class of anticancer drugs. Docetaxel (DTX) the prototype of this class has been approved for the treatment of broad range of cancers. However, to date the commercial preparation of DTX (Taxotere®) is accompanying adverse side effects, intolerance, and poor solubility, which can be overcome by encapsulating them using solid lipid nanoparticles (SLNs). SLNs represent versatile delivery system of drugs with newer forms such as polymer–solid lipid hybrid, surface modified and long circulating nanoparticles bringing forth improved prospects for cancer chemotherapy. In this review, the authors have discussed the current uses of various SLNs formulations of DTX with key emphasis on controlled and site‐specific drug delivery along with enhanced antitumour activity elucidated via in vitro and in vivo studies. Furthermore, the review article highlights few approaches that can be used in combination with existing DTX‐loaded SLNs to supplement DTX drug delivery.Inspec keywords: nanoparticles, nanomedicine, drug delivery systems, biomedical materials, cancer, reviews, tumoursOther keywords: docetaxel‐loaded solid lipid nanoparticles, drug delivery system, taxanes, anticancer drugs, Taxotere, SLN encapsulation, polymer‐solid lipid hybrid, surface modified nanoparticles, long circulating nanoparticles, chemotherapy, review  相似文献   
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