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991.
卵母细胞老化与许多不良因素有关,氧化应激和线粒体功能紊乱等均致其质量低下,影响进一步发育。作为卵母细胞老化的一种类型,排卵后卵母细胞老化(POA)在体外培养时较为常见,可造成卵母细胞质量下降、胚胎发育不良,导致妊娠率下降和出生缺陷增加。氧化应激是POA过程中的重要触发因素,可激活细胞凋亡通路,影响卵母细胞质量和胚胎发育潜能。现就近年来有关POA的影响因素、与氧化应激的相互作用关系以及使用不同抗氧化剂延缓POA的发生等方面研究进行综述。  相似文献   
992.
Abstract

The objective of the present study was to design and develop drug-device combination product in particular flunisolide nasal spray (FNS) using quality by design (QbD) approach. Quality target product profile (QTPP) of FNS was defined and critical quality attributes (CQAs), i.e. viscosity (cp) (Y1) and D50 droplet size distribution (DSD) (μm) (Y2) were identified. Potential risk factors were identified using a fish bone diagram and failure mode effect analysis (FMEA) tools. Plackett–Burman and Box–Behnken designs were used for screening the significant factors and optimizing the variables range, respectively. It was observed that viscosity (cp) (Y1) was significantly impacted by formulation variables X1: propylene glycol (PG) (%) and X2: polyethylene glycol (PEG) 3350 (%), while D50 DSD (μm) (Y2) was significantly impacted by formulation variables X1: PG (%), X2: PEG 3350 (%) and device variable X8: delivery volume (μl). A design space plot within which the CQAs remained unchanged was established at laboratory scale. In conclusion, this study demonstrated how QbD based development approach can be applied to the development of drug-device combination products with enhanced understanding of the impact of formulation, process and device variables on CQAs of drug-device combination products.  相似文献   
993.
Introduction: Today, over 20 million people suffer from Alzheimer’s disease (AD) worldwide. AD has become a critical issue to human health, especially in aging societies, and therefore it is a research hotspot in the global scientific community. The technology flow method differs from traditional reviews generating an informative overview of the research and development (R&D) landscape in a specific technological area. We need such an updated method to get a general overview of the R&D of anti-AD drugs in light of the dramatic developments in this area in recent years.

Areas covered: This study collects patent data from the Integrity database. A total of 399 patents with 821 internal citation pairs in the US from 1978 to 2017 were analyzed. Patent citation network analysis was used to visualize the technology relationship.

Expert opinion: For better production of anti-AD drugs, governments should emphasize the multi-target drug design, provide policy support for private companies, and encourage multilateral cooperation. The β-amyloid peptide (Aβ) theory leaves much to be desired; neurotransmitter and tau protein hypotheses are worth further examination. The use of old drugs for new indications is promising, as are traditional herbal medicines.  相似文献   

994.
995.

Background

Professional engagement has importance to the professional of pharmacy, and in particular the growth of student pharmacists. Measurement of this construct would allow investigation of factors that may increase or decrease professional engagement.

Objectives

To describe the development of the Student Pharmacist Inventory of Professional Engagement (S-PIPE), assess the factor structure and convergent validity, and test for differences in professional engagement based upon demographic and background factors.

Methods

Potential items for the S-PIPE were developed iteratively through inductive and deductive item-writing, 2 pilot administrations, expert review of items, and assessment of the content validity index, and cognitive interviews with students. The S-PIPE was administered to a cohort of 164 first year student pharmacists at University of Minnesota, along with items querying types and level of involvement in professional experiences and activities. An exploratory factor analysis was conducted using principal axis factoring extraction and Promax rotation. The number of factors to retain was based upon eigenvalues, examination of the scree plot, and a parallel analysis. Factors of the S-PIPE were compared to self-rated level of involvement and other demographic factors.

Results

Three factors were retained accounting for 70.7% of the variance, and named Belonging (α = 0.942, 9 items), Connectedness (α = 0.864, 3 items), and Meaningful Experience (α = 0.760, 4 items). All 3 factors were significantly correlated to self-rated involvement (r = 0.291 to 0.370). Level of professional engagement differed in this study by gender, and pharmacy work experience.

Conclusions

This study lays the foundation for quantitative research in professional engagement among student pharmacists. Future work is needed to further validate and extend these findings.  相似文献   
996.
《Vaccine》2018,36(41):6191-6201
Liposomal vaccines incorporating adjuvant and CD4 T cell helper peptides enhance antibody responses against weakly immunogenic B cell epitopes such as found in the membrane proximal external region (MPER) of the HIV-1 gp41 subunit. While the inclusion of exogenous helper peptides in vaccine formulations facilitates stronger and more durable antibody responses, the helper peptide incorporation strategy per se may influence the overall magnitude and quality of B cell target antigen immunogenicity. Both variability in individual peptide encapsulation as well as the potential for liposome surface-associated helper peptides to misdirect the humoral response are potential parameters impacting outcome. In this study, we used MPER/liposome vaccines as a model system to examine how the mode of the potent LACK T helper peptide formulation modulates antibody responses against the MPER antigen. We directly compared liposome surface-arrayed palmitoyl LACK (pLACK) versus soluble LACK (sLACK) encapsulated in the liposomes and free in solution. Independent of LACK formulation methods, dendritic cell activation and LACK presentation were equivalent in vivo. The frequency of MPER-specific GC B cells promoted by sLACK was higher than that stimulated by pLACK formulation, a finding associated with a significantly greater frequency of LACK-specific GC B cells induced by pLACK. While there were no significant differences in the quantity of MPER-specific serological responses, the MPER-specific antibody titer trended higher with sLACK formulated vaccines at the lower dose of LACK. However, pLACK generated relatively greater MPER-specific antibody affinities than those induced by sLACK-formulated vaccines. Overall, the results suggest that liposomal surface-associated LACK enhances immunogenicity of LACK through better engagement of LACK-specific B cells. Of note, this is not detrimental to the induction of MPER-specific immune responses; rather, the elicitation of higher affinity anti-MPER antibodies benefits from augmented help delivered via covalent linkage of the pLACK CD4 T cell epitope in conjunction with MPER/liposome presentation.  相似文献   
997.
998.
ABSTRACT

This article makes a review and reflection on parenting practices and child development in the perinatal period; the theoretical foundations and recent data in the field are exposed. Spanish and international research in this emerging area indicates that pregnancy, postpartum and early parenting are opportunities and unique spaces to develop competencies to create family contexts that promote healthy development. An exhaustive positive parenting proposal of early promotion of child development in the perinatal period is presented. This includes the promotion of: prenatal bond, couple's relationship, social support networks, the physical and mental health of the mother alongside with the support to make informed decisions about parenting and the development of parental knowledge of the intergenerational transmission of parenting patterns and of early childhood development. It is expected, that the proposal could be a tool in the future design of public intervention programmes with families.  相似文献   
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1000.
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