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排序方式: 共有329条查询结果,搜索用时 15 毫秒
71.
This study describes the construction and initial validation of the Asian American Family Conflicts Scale (FCS) with 3 samples of Asian American college students. The scale consists of 10 typical Asian American family conflicts that are rated for likelihood of occurrence (FCS-Likelihood) and seriousness of conflict (FCS-Seriousness). In Study 1, FCS-Likelihood and FCS-Seriousness had sound internal reliability, stability, and construct validity. In Study 2, FCS-Likelihood correlated with socioeconomic and cultural orientation variables. Ethnic, generation, and language differences, as well as the parent–child acculturation gap hypothesis, also were confirmed for FCS-Likelihood. In Study 3, FCS-Likelihood correlated with measures of family cohesion, adaptability, and parent-child communication. Although further validation is necessary, FCS-Likelihood in particular is a potentially useful research and clinical instrument for assessing the quality of Asian American parent–child relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Mangrove health in an arid environment encroached by urban development--a case study 总被引:2,自引:0,他引:2
Holguin G Gonzalez-Zamorano P de-Bashan LE Mendoza R Amador E Bashan Y 《The Science of the total environment》2006,363(1-3):260-274
Urban development will soon encroach upon several protected and largely unspoiled arid climate mangroves ecosystems located along the lagoon called Ensenada de La Paz in Baja California Sur, Mexico. Many of these mangroves are located on a large sandbar that separates the lagoon on the south side from Bahía de La Paz to the north. A general evaluation of the current status of these mangroves was conducted to establish biological and physicochemical indicators of the health of these mangroves to serve as a natural or predevelopment baseline in future management. The following parameters were measured in the feeding channels of the mangroves and at the mouth of the channels: vegetation coverage, species and health, and levels of dissolved oxygen, pH, salinity, total nitrogen, ammonium, nitrates and nitrites, phosphorus ions, and organic matter in sediments and seawater. The microbiological elements that were studied included aerobic bacteria, N2-fixing bacteria, inorganic phosphate solubilizers, coliform, and phytoplankton diversity. Bird populations were counted, with special attention to migratory and resident birds and protected and endangered species. A comprehensive analysis of all the elements indicated that the health of the sandbar mangrove populations is good despite the proximity of a modest urban center. It also demonstrated that several biological and physicochemical parameters used in this study, including the birds, can serve as indicators of mangrove health and as a baseline for future management of mangroves in regions with arid climates. 相似文献
73.
Gina Perrella Samantha J. Montague Helena C. Brown Lourdes Garcia Quintanilla Alexandre Slater David Stegner Mark Thomas Johan W. M. Heemskerk Steve P. Watson 《International journal of molecular sciences》2022,23(1)
Understanding the pathways involved in the formation and stability of the core and shell regions of a platelet-rich arterial thrombus may result in new ways to treat arterial thrombosis. The distinguishing feature between these two regions is the absence of fibrin in the shell which indicates that in vitro flow-based assays over thrombogenic surfaces, in the absence of coagulation, can be used to resemble this region. In this study, we have investigated the contribution of Syk tyrosine kinase in the stability of platelet aggregates (or thrombi) formed on collagen or atherosclerotic plaque homogenate at arterial shear (1000 s−1). We show that post-perfusion of the Syk inhibitor PRT-060318 over preformed thrombi on both surfaces enhances thrombus breakdown and platelet detachment. The resulting loss of thrombus stability led to a reduction in thrombus contractile score which could be detected as early as 3 min after perfusion of the Syk inhibitor. A similar loss of thrombus stability was observed with ticagrelor and indomethacin, inhibitors of platelet adenosine diphosphate (ADP) receptor and thromboxane A2 (TxA2), respectively, and in the presence of the Src inhibitor, dasatinib. In contrast, the Btk inhibitor, ibrutinib, causes only a minor decrease in thrombus contractile score. Weak thrombus breakdown is also seen with the blocking GPVI nanobody, Nb21, which indicates, at best, a minor contribution of collagen to the stability of the platelet aggregate. These results show that Syk regulates thrombus stability in the absence of fibrin in human platelets under flow and provide evidence that this involves pathways additional to activation of GPVI by collagen. 相似文献
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RC Vasavada C Cavaliere AJ D'Ercole P Dann WJ Burtis AL Madlener K Zawalich W Zawalich W Philbrick AF Stewart 《Canadian Metallurgical Quarterly》1996,271(2):1200-1208
Parathyroid hormone-related protein (PTHrP) is produced by the pancreatic islet. It also has receptors on islet cells, suggesting that it may serve a paracrine or autocrine role within the islet. We have developed transgenic mice, which overexpress PTHrP in the islet through the use of the rat insulin II promoter (RIP). Glucose homeostasis in these mice is markedly abnormal; RIP-PTHrP mice are hypoglycemic in the postprandial and fasting states and display inappropriate hyperinsulinemia. At the end of a 24-hour fast, blood glucose values are 49 mg/dl in RIP-PTHrP mice, as compared to 77 mg/dl in normal littermates; insulin concentrations at this time are 6.3 and 3.9 ng/ml, respectively. Islet perifusion studies failed to demonstrate abnormalities in insulin secretion. In contrast, quantitative islet histomorphometry demonstrates that the total islet number and total islet mass are 2-fold higher in RIP-PTHrP mice than in their normal littermates. PTHrP very likely plays a normal physiologic role within the pancreatic islet. This role is most likely paracrine or autocrine. PTHrP appears to regulate insulin secretion either directly or indirectly, through developmental or growth effects on islet mass. PTHrP may have a role as an agent that enhances islet mass and/or enhances insulin secretion. 相似文献
77.
This paper describes the architecture of a system, a prototype of which is being developed by the authors at IBM Rome Scientific Centre, providing an interactive approach to the printing process, starting from the input of the basic components (images, texts and graphics) up to the definition and modification of page layout and finally to driving high resolution output devices. The system manages collections of pages, called “documents”; in turn each page is defined as a spatial composition of elementary boxes distributed on different levels. The main characteristics of the system architecture are interactivity, modularity and non-procedurality (the user has only to describe “what” has to be done, rather “how” to do it). 相似文献
78.
EE Calore MJ Cavaliere NM Perez V Takayasu A Wakamatsu MH Kiss 《Canadian Metallurgical Quarterly》1995,22(12):2246-2249
OBJECTIVE: Systemic sclerosis (SSc) is characterized by abnormal deposition of collagen in the skin and by visceral involvement. Muscle weakness is a relatively frequent complication of SSc, although severity varies. We studied muscle pathology in patients with SSc with progressive muscle involvement. METHODS: We performed histochemical and immunohistochemical investigations to detect neural cell adhesion molecule (NCAM). RESULTS: Five of the 6 cases of SSc expressed NCAM in atrophic angulated fibers (some fibers stained heavily with oxidative enzymes). CONCLUSION: Neurogenic involvement in SSc is more frequent than reported. 相似文献
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We survey and extend the work on the paradigm called “computing by observing”. Its central feature is that one considers the behavior of an evolving system as the result of a computation. To this purpose an external observer records this behavior. In this way, several computational trade-offs between the observer and the observed system can be determined. It has turned out that the observed behavior of computationally simple systems can be very complex, when an appropriate observer is used. For example, a restricted version of context-free grammars with regular observers suffices to obtain computational completeness. As a second instantiation presented here, we apply an observer to sticker systems, an abstract model of DNA computing. Finally, we introduce and investigate the case where the observers can read only one measure of the observed system (e.g., mass or temperature), modeling in this way the limitations in the observation of real physical systems. Finally, a research perspective on the topic is presented. 相似文献