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111.
This article examines ethnographic data collected from indigenous Alaskan women who participated in a menstrual cycle study conducted by The Tremin Trust Research Program, initially known as the Menstruation and Reproductive History Program (MRH). In the 1960s, the MRH program was expanded to Alaska to study non‐Caucasian women's menstrual cycles. In addition, an ethnographer collected data through participation observation from some 345 women who participated in the MRH study. These data were recorded in field notebooks during site visits to Alaskan villages. Major themes and contextual information were identified in the data that described the daily lives of the women and their experiences as research participants. Eskimo women described the cultural conflicts that arose during the conduct of the menstrual studies and problems encountered when the investigators failed to account for the traditional gender roles in Eskimo society. Cultural differences were apparent when the women described the culturally inappropriate health education provided by the research team. The goals of the menstrual cycle study emphasized research progress rather than the health needs of the research participants; this emphasis accentuated the severity of health problems and the lack of health services experienced by Eskimo women.  相似文献   
112.
AimThe aim of this study was to evaluate impact of the EPICS Family Bundle on stress and coping.BackgroundCritical care nurses frequently deal with family stress, but may be without knowledge and skills needed to assist families to cope.MethodsA non-equivalent control group design was used, with a convenience sample of 84 family members of critically ill patients. During the control phase, participants completed tools measuring stress and coping. The intervention included use of the EPICS Family Bundle. After implementation, participants completed the same tools as those administered during the control phase. Outcomes were analyzed using independent-sample t-tests.ResultsThe experimental group had a significantly higher coping score on two subscales; and although not statistically significant, it was also improved on an additional four.ConclusionAfter implementation of the intervention, families experienced improved coping. The study may have lacked sufficient power to detect all differences.  相似文献   
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114.
Abstract

To meet the need for emotional support for family members of terminal patients, a weekly group session was established on a cancer unit. The group has allowed family members to share their fears, concerns, and doubts as well as receive support from other individuals experiencing similar traumatic situations. The development and goals of this group are discussed.  相似文献   
115.
魏峰  楼之岑  刘一民  缪振春   《药学学报》1994,29(7):511-518
从川续断(Dipsacus asperoides c.Y.cheng et T.M.Ai)根部的乙醇提取物中得到二个新三萜皂甙,命名为川续断皂甙(asperosaponins)F和H1。川续断皂甙F(I)是含六个糖的皂甙,川续断皂甙H1(II)是含八个糖的皂甙。运用化学方法及光谱(1HNMR,13CNMR,1H-1H COSY,——维多重接力COSY,选择性远程DEPT和三重共振NOE差谱)解析,鉴定其结构分别为3-O-[β-D-吡喃木糖(1→4)-β-D-吡哺葡萄糖(1→4)][α-L-吡喃鼠李糖(1→3)]-β-D-吡喃半乳糖(1→3)-α-L-吡喃鼠李糖(1→2)-α-L-吡喃阿拉伯糖-常春藤皂甙元(I)和3-0-[β-D-吡喃木糖(1→4)-β-D-吡喃葡萄糖(1→4)][α-L-吡喃鼠李糖(1→3)]-β-D-吡喃半乳糖(1→3)-α-L-吡喃鼠李糖(1→2)-α-L一吡喃阿拉伯糖-常春藤皂甙元-28-O-β-D-吡喃葡萄糖(1→6)-β-D-吡喃葡萄糖酯甙(II)。并总结出一些光谱方面的变化规律,可用于糖的鉴定,以及构型、糖链的连接顺序和糖与甙元之间的连接位置的说明。  相似文献   
116.
Purpose: We previously developed a novel cryo-thermal therapy to treat malignant mammary carcinoma and melanoma in a mouse model; long-term survival and CD4+ T cell orchestrating anti-tumor immune memory response were achieved. Moreover, cryo-thermal-induced CD4+ T cell differentiation into Th1 and CD4+CTL sub-lineages, in which M1 macrophage polarization played a direct, important role. In particular, cryo-thermal therapy triggered M1 macrophage polarization with up-regulated expression of C–X–C motif ligand 10 (CXCL10) and Interleukin 6 (IL-6). But whether CXCL10 and IL-6 contribute to CD4+ T cell-mediated anti-tumor immunity remains unclear. In this study, the role of cryo-thermal-induced CXCL10 and IL-6 in anti-tumor immunity was determined.

Methods: The level of CXCL10 and IL-6 in spleen and serum was determined by RT-PCR and ELISA on day 14 after cryo-thermal therapy. Splenic dendritic cells (DCs) and macrophages were isolated from cryo-thermal-treated mice on day 5 and 14, and the level of CXCL10 and IL-6 in macrophages and DCs was determined by ELISA. The transwell migration assay was performed to study immune cell migration. In vivo neutralization of CXCL10 or IL-6 was performed to investigate the phenotypic changes of immune cells.

Results: Cryo-thermal therapy induced M1 macrophage polarization with up-regulation of CXCL10 and IL-6 expression in spleen. CXCL10 and IL-6 promoted DCs migration and maturation, and subsequently promoted CD4+ T cell migration and differentiation into Th1 and CD4+ CTL, moreover, reduced myeloid-derived suppressor cells (MDSCs) accumulation.

Conclusions: Cryo-thermal-induced CXCL10 and IL-6 created acute inflammatory environment to initiate a systemically cascading innate and adaptive anti-tumor immunity, which was more permissive for tumor eradication.  相似文献   

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118.
Metallic glass (MG) is an important new category of materials, but very few rigorous laws are currently known for defining its “disordered” structure. Recently we found that under compression, the volume (V) of an MG changes precisely to the 2.5 power of its principal diffraction peak position (1/q1). In the present study, we find that this 2.5 power law holds even through the first-order polyamorphic transition of a Ce68Al10Cu20Co2 MG. This transition is, in effect, the equivalent of a continuous “composition” change of 4f-localized “big Ce” to 4f-itinerant “small Ce,” indicating the 2.5 power law is general for tuning with composition. The exactness and universality imply that the 2.5 power law may be a general rule defining the structure of MGs.Metallic glasses (MGs) possess many unique and superior properties, such as extremely high strength, hardness, and corrosion resistance, etc., making them promising metallic materials with widespread applications (1, 2). Thousands of MGs with a wide range of compositions and properties have been synthesized over the past decades. However, so far the development of MGs is mainly based on tedious composition mapping in multicomponent space to pinpoint the combination of elements with optimized glass-forming ability (GFA). This method for development of MGs is a time- and resource-intensive strategy of trial and error which highlights the need for the guidance of a general theory (2, 3). Intensive research effort has been devoted to finding general rules in various MGs to understand the fundamentals and to guide the development of new MGs (4, 5). Quantitative correlations between their properties have been observed. For instance, compressive yield strength and elastic moduli of MGs are found to be intimately connected with their glass transition temperature Tg (610), and the ductility, fragility (11, 12), and Poisson’s ratio of MGs are closely related (1316). The extensive correlations in properties suggest that the disordered MGs may share general rules in their structure. To clarify this scenario, detailed and accurate structural information spanning short range to long range is required. However, the current experimental probes and theories are limited to local structure in MGs (17). Therefore, understanding how the atoms efficiently fill up the 3D space and how this controls the bulk properties of MGs remains a long-standing theoretical challenge (1823). To date, few general and exact rules regarding structure–property relationships have been established in MGs (23).Encouraging progress on understanding structure–property relationships in MGs has recently been made through the discoveries of the noncubic (2.3 or 2.5) power laws that correlate the principal diffraction peak (PDP) position q1 with the bulk density ρ or average atomic volume, Va, i.e., ρ∝(q1)D or Va∝(1/q1)D, where D equals ∼2.3 with varying the composition of MGs at ambient pressure (19) or ∼2.5 for tuning the density of MGs with pressure (22, 24). Whereas composition and pressure show similar exponents in the power laws in MGs, composition and pressure are two independent variables for controlling the density (volume) of materials; they usually have dramatically different effects on MGs. For example, pressure is thought to cause only elastic densification in MGs without obvious structural change because of their already densely packed structure; the structure and properties of MGs are very sensitive to even minor compositional variations (25, 26). In addition, to achieve composition change, different samples usually have to be synthesized. And, many other variables are thought to be inevitably involved, making the compositional change complex (23). Therefore, some basic questions have been perplexing to the glass community: Why do “complex” compositional and “simple” pressure power laws show similar exponents? Is there any connection between them? These questions remain unanswered and have been the major obstacle in understanding the nature of these noncubic power laws.To address these questions, a systematic study in the 2D pressure-composition space seems to be required. However, the consistency of the data in this kind of study will be questionable. Alternatively, in the present study, we choose the polyamorphous Ce68Al10Cu20Co2 MG as a model system. It is well known that Ce-based MG systems show a polyamorphic transition between ∼2 GPa and ∼5 GPa caused by the pressure-induced 4f electron localized-to-itinerant transition (27, 28). During this polyamorphic transition, both the atomic size and the electronegativity of Ce are significantly changed (29). Composition tuning in MGs mainly means the variation of atomic size and electronegativity of components, which controls the formation of MGs (30). Therefore, although nothing changes in the nucleus, for MGs this pressure-induced polyamorphic transition is equivalent to a continuous “composition” change with the 4f-localized “big Ce” gradually substituted by 4f-itinerant “small Ce.” As a result, we are able to vary both pressure and composition of a MG in a well-controlled way for the first time, to our knowledge.  相似文献   
119.
120.
Astilbin (ASN) is a flavonoid compound isolated from the rhizome of Smilax china L. (Smilacaceae). It has many bioactivities, such as selective immunosuppression, antioxidant, anti-hepatic injury, etc., and is widely used in traditional Chinese medical treatments. The interaction of ASN with bovine serum albumin (BSA) was studied in a physiological buffer (pH = 7.40) using multi-spectroscopic techniques in combination with molecular docking methods. UV-vis absorption measurements proved that a ASN–BSA complex could be formed. Fluorescence data revealed that ASN could strongly quench the intrinsic fluorescence of BSA in terms of a static quenching procedure. The process of binding was spontaneous and the binding occurred mainly through hydrogen bonding and van der Waals forces. The distance r between donor (BSA) and acceptor (ASN) was calculated to be 4.80 nm based on Förster''s non-radiative energy transfer theory. The binding constant (Ka = 7.31 × 104 mol L−1) and the number of binding sites (n ≈ 1) at 298 K suggested that ASN only occupied one site in BSA with high affinity. Moreover, the results of molecular docking indicated that ASN was more likely to be located in site I (sub-domain IIA) of BSA. The results of synchronous fluorescence and three-dimensional fluorescence spectra showed that ASN induced conformational changes of BSA. The findings would be beneficial for research on the transportation, distribution and some important bioactivities of ASN in the human body.

The interaction of astilbin with bovine serum albumin was confirmed by multi-spectroscopic techniques and molecular docking methods.  相似文献   
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