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排序方式: 共有8803条查询结果,搜索用时 31 毫秒
81.
Pablo Martinez-Perez Domingo Orozco-Beltrán Francisco Pomares-Gomez Juan L. Hernández-Rizo Anna Borras-Gallen Vicente F. Gil-Guillen Jose A. Quesada Adriana Lopez-Pineda Concepción Carratala-Munuera 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2021,53(2):101942
AimsTo validate a translated and culturally adapted version of the Morisky Medication Adherence Scale for use in Spanish population, and to examine the psychometric properties of this scale in patients with type 2 diabetes mellitus in Spain.DesignThis cross-sectional study was conducted in a single university hospital in Spain. Patients diagnosed with type 2 diabetes mellitus at least 1 year before inclusion, being treated with anti-diabetic medication were included.InterventionWe used the Spanish version of the scale to measure treatment adherence.Principal measurementsthree level categorical scale is broken down into low adherence (score of <6), medium adherence (score of 6 to <8) and high adherence (score of 8). To validate the questionnaire, we measured internal consistency through Cronbach's α, confirmed construct validity through an exploratory principal component analysis and assessed test–retest reliability.Results232 patients met the inclusion criteria. The Cronbach's α coefficient was 0.40 (95% CI 0.28–0.52). The exploratory principal component analysis showed three components. The intraclass correlation coefficient was 0.718 (95% CI 0.564–0.823).Conclusionsthe Spanish version of the Morisky Medication Adherence scale showed low internal consistency, the exploratory factor analysis identified three dimensions, and the test–retest reliability was acceptable, therefore, psychometric properties of MMAS-8 are not suitable for measuring medication adherence in type 2 diabetes mellitus patients from Spain. 相似文献
82.
Hoffmann M Gaikwad J Schmalz G Cavender A D'Souza R 《Connective tissue research》2002,43(2-3):376-380
Studying the mechanisms of molecular interactions in developing tissues demands sensitive molecular biological in vivo and in vitro techniques. Laser capture microdissection (LCM) allows for the isolation of mRNA in histological sections even from single cells, thus enabling the identification of in vivo gene expression products in closely circumscribed tissue areas. The aims of this study were to assess the optimal fixation, processing, and staining conditions to retrieve RNA from microdissected odontoblasts. Fluorometric assays and RT-PCR analysis of alpha 1(I) collagen, dentin sialophosphoprotein (Dspp), and osteocalcin (OC) confirmed that the total RNA isolated from day 0 and day 3 captured odontoblasts was sufficient in quantity and quality. Our results indicate that individual odontoblasts obtained by LCM are morphologically intact and chemically unaltered, allowing accurate molecular and biochemical analyses. 相似文献
83.
84.
Targeted liposomal c-myc antisense oligodeoxynucleotides induce apoptosis and inhibit tumor growth and metastases in human melanoma models. 总被引:7,自引:0,他引:7
Fabio Pastorino Chiara Brignole Danilo Marimpietri Gabriella Pagnan Adriana Morando Domenico Ribatti Sean C Semple Claudio Gambini Theresa M Allen Mirco Ponzoni 《Clinical cancer research》2003,9(12):4595-4605
PURPOSE: Melanoma is a highly malignant and increasingly common tumor. Because the cure rate of metastatic melanoma by conventional treatment is very low, new therapeutic approaches are needed. We previously reported that coated cationic liposomes (CCL) targeted with a monoclonal antibody against the disialoganglioside (GD(2)) and containing c-myb antisense oligodeoxynucleotides (asODNs) resulted in a selective inhibition of the proliferation of GD(2)-positive neuroblastoma cells in vitro. EXPERIMENTAL DESIGN: Here, we tested the in vivo antitumor effects of this novel antisense liposomal formulation by targeting the c-myc oncogene on melanoma, a neuroectodermal tumor sharing with neuroblastoma the expression of GD(2). RESULTS: Our methods produced GD(2)-targeted liposomes that stably entrapped 90% of added c-myc asODNs. These liposomes showed a selective binding for GD(2)-positive melanoma cells in vitro. Melanoma cell proliferation was inhibited to a greater extent by GD(2)-targeted liposomes containing c-myc asODNs (aGD(2)-CCL-myc-as) than by nontargeted liposomes or free asODNs. The pharmacokinetic results obtained after i.v. injection of [(3)H]-myc-asODNs, free or encapsulated in nontargeted CCLs or GD(2)-targeted CCLs, showed that free c-myc-asODNs were rapidly cleared, with less than 10% of the injected dose remaining in blood at 30 min after injection. c-myc-asODNs encapsulated within either CCL or aGD(2)-CCL demonstrated a more favorable profile in blood, with about 20% of the injected dose of each preparation remaining in vivo at 24 h after injection. In an in vivo melanoma experimental metastatic model, aGD(2)-CCL-myc-as, at a total dose of only 10 mg of asODN per kilogram, significantly inhibited the development of microscopic metastases in the lung compared with animals treated with myc-asODNs, free or entrapped in nontargeted liposomes, or aGD(2)-CCL encapsulating scrambled asODNs (P < 0.01). Moreover, mice bearing established s.c. human melanoma xenografts treated with aGD(2)-CCL-myc-as exhibited significantly reduced tumor growth and increased survival (P < 0.01 versus control mice). The mechanism for the antitumor effects appears to be down-regulation of the expression of the c-myc protein and interruption of c-myc-mediated signaling: induction of p53 and inhibition of Bcl-2 proteins, leading to extensive tumor cell apoptosis. CONCLUSION: These results suggest that inhibition of c-myc proto-oncogene by GD(2)-targeted antisense therapy could provide an effective approach for the treatment of melanoma in an adjuvant setting. 相似文献
85.
David Quintanar-Guerrero David Tamayo-Esquivel Adriana Ganem-Quintanar Eric Allémann Eric Doelker 《European journal of pharmaceutical sciences》2005,26(2):211-218
In this study, the emulsification-diffusion method traditionally used to prepare polymeric nanoparticles was adapted to obtain lipidic nanospheres (LN) using four model lipids. The method consists of dissolving the lipid in a partially water-miscible solvent (previously saturated with water) at room temperature or at controlled temperature depending on lipid solubility. This organic phase is emulsified in an aqueous solution of a stabilizing agent (saturated with solvent) by conventional stirring at the same temperature used to dissolve the lipid. This oil-in-water emulsion is then diluted with an excess of water at controlled temperature in order to provoke the diffusion from the internal phase into the external phase thereby causing lipid aggregation in the form of LN. This new approach for the preparation of LN has clear advantages over the existing methods, namely: (i) it is efficient and versatile; (ii) easy implementation and scaling up (with no need of high energy sources); (iii) high reproducibility and narrow size distribution; (iv) less physical stress (i.e., long exposure to high temperatures and to mechanical dispersion); (v) it is not necessary to dissolve the drug in the melted lipid. The selection of the water-miscible solvent and the stabilizers are critical parameters to obtain lipidic particles in the nanometric range. In general, solvents with high water miscibility and stabilizers able to form stable emulsions are preferred. The results demonstrated that it was possible to reduce the particle size by increasing the process temperature, the stirring rate, the amount of stabilizer, and by lowering the amount of lipid. Control of the preparative variables allowed to obtain LN with diameters under 100 nm. It was found that the influence of preparative parameters was associated with a mechanism based on a physicochemical instability. In this sense, it is suggested that the rapid solvent diffusion produces regions of local supersaturation near the interface, and LN are formed due to the ensuing interfacial phase transformations and lipid aggregation that occur in these interfacial domains. In terms of stability, only poly(vinyl alcohol) (PVAL) was able to preserve the physical stability of the dispersion for long periods after preparation. This effect was attributed to the ability of PVAL chains to form a strongly attached layer on the nanoparticle surface with an excellent repulsion effect. 相似文献
86.
87.
In vitro development of engineered muscle using a scaffold based on the pressure‐activated microsyringe (PAM) technique 下载免费PDF全文
Daniele Cei Adriana Malena Carmelo de Maria Emanuele Loro Federica Sandri Giulia del Moro Sara Bettio Lodovica Vergani Giovanni Vozzi 《Journal of tissue engineering and regenerative medicine》2017,11(1):138-152
The development of new human skeletal muscle tissue is an alternative approach to the replacement of tissue after severe damage, for example in the case of traumatic injury, where surgical reconstruction is often needed following major loss of natural tissue. Treatment to date has involved the transfer of muscle tissue from other sites, resulting in a functional loss and volume deficiency of donor sites. Approaches that seek to eliminate these problems include the relatively new solution of skeletal muscle engineering. Here there are two main components to consider: (a) the cells with their regenerative potential; and (b) the polymeric structure onto which cells are seeded and where they must perform their activities. In this paper we describe well‐defined two‐ and three‐dimensional polymeric structures able to drive the myoblast process of adhesion, proliferation and differentiation. We examine a series of polymers and protein adhesions with which to functionalize the structures, and cell‐seeding methods, with a view to defining the optimal protocol for engineering skeletal muscle tissue. All polymer samples were tested for their mechanical and biological properties, to support the validity of our results in the real context of muscle tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
88.
89.
Elizabeth Piñón-Segundo Adriana Ganem-Quintanar Juan Rafael Garibay-Bermúdez José Juan Escobar-Chávez Miriam López-Cervantes David Quintanar-Guerrero 《Pharmaceutical development and technology》2013,18(4):493-501
Submicron colloidal suspensions of poly(ε-caprolactone) (PCL) were prepared by the solvent displacement method, using either the conventional form or a new recirculation device. In the latter case, a process that allows the recirculation of the aqueous phase into a device, providing a continuous flow, is proposed. The influence of the organic solution injection rate and polymer concentration on mean particle size and process yield were studied for both methods. The recirculation rate was also analyzed for the recirculation system. Nanoparticles (NPs) showed mean sizes that ranged from 156 to 381. The smallest particles were obtained when recirculation rate, injection rate and polymer concentration were maximized but at the expense of the yield. The only acceptable yields (83–96%) were obtained at the lowest PCL concentration (2.5% w/v). ANOVA tests (α = 0.05) showed that the variables implicated in the recirculation system significantly affected the mean particle size and the process yield. The entrapment efficiencies of NPs prepared by the conventional method were not significantly different (α = 0.05) from those obtained by the recirculation system. 相似文献
90.
René Andrade Machado Víctor Frades García Adriana Goicoechea Astencio Vanessa Benjumea Cuartas 《Seizure》2013,22(10):846-855
PurposeControlled randomized studies recommending the clinical use of lamotrigine in adult populations with the diagnosis of Juvenile Myoclonic Epilepsy are still lacking. To compare the efficacy and tolerability of lamotrigine versus valproate in adult patients with JME.MethodsThis was a prospective, randomized, controlled, pragmatic, long-term and open-label treatment trial. Patients were randomized to use valproate or lamotrigine. The primary end points of the study were: (1) time from randomization to treatment failure (withdrawal); (2) time from randomization to seizures remission. Secondary ending points were: (1) frequency of clinically important adverse events and (2) change in the QOLIE-31 after randomization. The definition of seizure remission was based on disappearance of all seizure types and EEG discharges.ResultsWe found that the time to withdraw treatment after randomization was not significantly different in lamotrigine and valproate groups. Long-term seizures freedom was equal in the both groups of the trial; only 8 (19.1%) patients randomized to lamotrigine and 6 (19.4%) randomized to valproate were not seizure free after 4 months of treatment. Between 17.03% (lamotrigine) and 35.3% (valproate) of patients reported adverse reactions at some point in the intention-to treat study (p = 0.07). All subscales of the QOLIE-31 questionnaire, except that related to side effects of medication, improved more than 5 points with respect to baseline period in both groupsConclusionLamotrigine is effective in adult patients with Juvenile Myoclonic Epilepsy and better tolerated than valproate, although the incidence of idiosyncratic reactions could be a cause of concern. 相似文献