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The kinetics of Polymerization of acrylonitrile initiated by the redox systems cyanoacetic acid/Mn(III) and 2-butanone/Mn(III) were investigated in the temperature range of 30 – 50°C in aqueous sulfuric acid. The kinetics are consistent with the formation of a 1 : 1 complex between the reducing agent and Mn(III), its unimolecular decomposition yielding the initiating radical. Extensive oxidation of the primary radical with exclusively mutual termination of growing radicals accounts for the kinetics of the polymerization. Rate and equilibrium constants as well as thermodynamic parameters were evaluated and their significance is discussed.  相似文献   
3.
Poly(vinyl chloride) (PVC) was aminated by treating the resin with a concentrated aqueous solution of ethylenediamine. The aminated PVC was then reacted with hexamethylene diisocyanate to incorporate the isocyanate group onto the polymer backbone. The isocyanated PVC was further reacted with poly(ethylene glycol) (PEG) of molecular weight 600 Da. The modified polymer was characterized using infrared and X-ray photoelectron spectroscopy (XPS) and thermal analysis. Infrared and XPS spectra showed the incorporation of PEG onto PVC. The thermal stability of the modified polymer was found to be lowered by the incorporation of PEG. Contact angle measurements on the surface of polymer films cast from a tetrahydrofuran solution of the polymer demonstrated that the modified polymer gave rise to a significantly hydrophilic surface compared to unmodified PVC. The solid/water interfacial free energy of the modified surface was 3.9 ergs/cm(2) as opposed to 18.4 ergs/cm(2) for bare PVC surface. Static platelet adhesion studies using platelet-rich plasma showed significantly reduced platelet adhesion on the surface of the modified polymer compared to control PVC. The surface hydrophilicity of the films was remarkably retained even in the presence of up to 30 wt% concentration of the plasticizer di-(2-ethylhexyl phthalate). The study showed that bulk modification of PVC with PEG using appropriate chemistry can give rise to a polymer that possesses the anti-fouling property of PEG and such bulk modifications are less cumbersome compared to surface modifications on the finished product to impart anti-fouling properties to the PVC surface.  相似文献   
4.
Peripheral giant cell granuloma is a lesion arising mainly from the connective tissue of gingiva or periosteum of alveolar ridge. A case of peripheral giant cell granuloma involving a deciduous molar and the succedaneous tooth is reported. The lesion was large and interfered with occlusion. Surgical excision of the lesion along with the deciduous first molar was done. The underlying permanent first premolar was also involved, and had to be removed. The importance of an adequate salivary flow and maintenance of oral hygiene in the prevention of such lesions is stressed.  相似文献   
5.

Table of Contents

Contents Volume 32 No. 1 (2000) Section One: International Urology and Nephrology  相似文献   
6.
There has been a surge in haploidentical hematopoietic stem cell transplantation (HSCT) in India recently. However, there is a paucity of data on haploidentical HSCT from India. The report is an analysis of data of haploidentical HSCT performed at our center. Analysis of patients with acute leukemia or chronic myeloid leukemia who underwent haploidentical HSCT during 2014–2019 was performed. The graft versus host disease (GVHD) prophylaxis was post-transplant Cyclophosphamide with Mycophenolate-mofetil and Cyclosporine. All patients were transfused peripheral blood stem cells from donors. Overall survival (OS) was calculated using the Kaplan–Meier method. Twenty-one patients underwent haploidentical HSCT. Fourteen-patients were males. The median age of patients was 15 years. Fludarabine with total body irradiation was the most common conditioning regimen (n = 15, 71.4%). The median duration for neutrophil and platelet engraftment was 14 days. Cumulative incidence of acute and chronic GVHD was 19%, and 38% respectively. The median follow-up was 26 months and the two-year OS was 38%. Twelve (57%) patients died during the study period, 8 patients (38%) died from transplant-related mortality (TRM), and 4 from disease relapse. Sepsis was the cause of death in six of the eight TRM. Nine out of 21 patients (42.8%) are leukemia-free on follow-up. Haploidentical HSCT is a promising modality of treatment in patients who have no suitable matched donors. Though the TRM remains high, good disease control was achieved in 42.8% of patients. Multi-drug resistant bacterial infection remains a challenge in performing haploidentical HSCT in developing countries.  相似文献   
7.
Atherosclerosis is regarded as the disease of the arterial vasculature. The main characteristics of atherosclerosis are the abnormal accumulation of lipids, increased inflammatory cells, matrix deposits, and proliferation of smooth muscle cells. Diabetes mellitus, obesity, and hyperlipidemia are the most studied risk factors of atherosclerosis. One least studied risk factor is the uric acid (UA), a high UA in circulation is interlinked with many pathological processes. Several epidemiological studies suggest elevated UA levels as an essential biomarker in the forecast of several cardiovascular diseases. Available evidence claims that UA upholds the atherosclerosis process via disturbing lipid metabolism, reducing the nitric oxide synthesis in endothelial cells, promoting the proliferation of vascular smooth muscle cells, and overwhelms inflammation. In endothelial dysfunction and coronary artery lesions, UA is considered as an independent predictor. The updated studies on the involvement of hyperuricemia in atherosclerosis prove that treatment with xanthine oxidase (XO) inhibitors not just benefits the treatment of hyperuricemia but also reduces the burden of atherosclerosis to a greater extent. In this review, we highlight how the hyperuricemia affects vascular integrity, causes atherosclerosis, and the mechanism of action of XO inhibitors on atherosclerosis.  相似文献   
8.
Abstract

As mannose receptors are known to be over-expressed in cancer cells, we synthesized polymannose-doxorubicin (PM-DOX) conjugates with the objective of targeting the drug to cancer cells. DOX was conjugated to oxidized PM through Schiff’s linkages to obtain PM-DOX conjugates. In order to examine the superior targeting efficacy of PM-DOX conjugate, sodium alginate (SA) was conjugated to DOX by similar chemistry and compared with PM-DOX conjugate. The cytotoxicity of the conjugates was investigated in A549 cell lines using MTT Assay and the cell uptake and retention studies, were performed using flow cytometry and cell imaging. In vitro drug release studies with both PM-DOX and SA-DOX conjugates showed an initial burst release of DOX up to 37–39% at 1?h, followed by a steady release up to 58–62% at 24?h in human plasma while negligible release was observed in phosphate buffered saline. The conjugates exhibited negligible hemolytic potential to human erythrocytes compared to free DOX. The PM-DOX conjugate showed better cytotoxic potential against A549 cells at lower concentration (equivalent to 0.27?μg/mL of DOX) at 72?h compared to free DOX and SA-DOX conjugate. Further, PM-DOX conjugate showed enhanced uptake by the cells in comparison with SA-DOX conjugate thereby confirming the target specificity of PM to the cancer cells.  相似文献   
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Varicose veins (VVs) are generally characterized by their elongated, twisted, bulging, superficial appearance on the lower extremities and usually present with acute or chronic venous diseases. Despite diagnostic and surgical advances in the management of VV, patients suffer from post-therapeutic complications and recurrence. We present findings from a retrospective study of a modified treatment modality in patients with varicose veins who attended St. Thomas Institute of Research on Venous Diseases, Changanassery, Kerala. The hospital caters to patients from India and outside. Out of 14,707 patients treated from 1997 till May 2013, 6,350 patients from January to March 2011 were selected for the study from the routine clinical practice (mid-segment) to facilitate follow-up. They were categorized according to Clinical Etiologic Anatomic Pathophysiologic (CEAP) clinical classification system. Baseline data were accrued using a questionnaire. Patients were treated by microfoam sclerotherapy giving a maximum importance to smaller veins, depicting a modified technique of microfoam sclerotherapy (MMFST). This is based on the significance of microscopic venous valves (MVVs) in the development of chronic venous disease (CVD). Follow-up was according to a predefined schedule, and improvements and complications were recorded. A positive family history of VVs was reported in 85.23 % of patients. Half the study population belonged to CEAP clinical class IV. There were no significant complications in patients throughout the 2 to 6 years of follow-up. Recurrence was rarely reported during follow-up and was corrected by repeating the procedure as required during follow-up. MMFST is an innovation in the treatment of VVs based on new principles, with the potential to control and revert the symptoms of CVD, with minimal complications.  相似文献   
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