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1.
目的:明确集中的电话干预能否降低慢性心衰门诊患者死亡或因心衰加重而住院的发生率。设计:多中心、随机对照试验。地点:阿根廷的51个中心(包括公立、私立的医院及流动设施)。参与者:1518例患有稳定的慢性心衰且已接受最佳药物治疗方案治疗的门诊患者,由心脏科主治医师分层后随机分为电话干预组和常规治疗组。干预:在常规治疗的基础上,由一个中心通过护士频繁的电话随访对患者进行教育、辅导和监督。主要观察指标:全因死亡或由于心衰加重而住院。结果:99.5%的患者完成了全部随访。常规治疗组758例患者中由于心衰加重而住院或死亡的比例(235…  相似文献   
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Ultraviolet (UV) radiation is one of the important cataract risk factors. The present studies examined the hypothesis that this effect is due to the UV penetration through the cornea and subsequent induction of a photochemical generation of reactive species of oxygen (ROS) in the aqueous and lens. The hypothesis was ascertained by rat lens organ culture studies conducted under UV (365 nm), with media containing micromolar levels of riboflavin, with and without pyruvate, the latter acting as an ROS scavenger. The implication of ROS in the UV-induced damage was confirmed by measurements of peroxide generation. Damage to the lens was assessed physiologically by measuring the decrease in its active transport of rubidium ions. Biochemically, it was assessed by measuring the lowering of adenosine triphosphate and glutathione. The incorporation of pyruvate in the medium protected the lens against these deleterious effects. That the beneficial effect of pyruvate is attributable to its ROS-scavenging property was proven by the peroxide depletion in its presence, commensurate with its own utilization in parallel. A protective effect of this keto acid against UV-induced tissue damage has been shown for the first time, suggesting its clinical usefulness against UV irradiation-induced pathologies. Hence, further studies on the possible protective effects of such alpha-keto acids against UV damage are in progress.  相似文献   
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Some features of the formation, expression and inheritance of basic genetic and androgen programs of the level of unusual estrogen-binding protein (UEBP) in mature female rat hepatocytes under experimental conditions were investigated. Liver regeneration after partial (2/3) hepatectomy of mature rats was used for generation of a new population of differentiated hepatocytes. The UEBP content was determined by radioligand technique in control liver and at 2, 4, 14 days of liver regeneration and related to the total DNA content as an indicator of cell proliferative activity. It was revealed that the basic genetic program of low UEBP level of hepatocytes of ovariectomized females was fully transferred to daughter cell during cell proliferation and characterized by a temporary elevation of its expression during initial steps of liver regeneration. It was shown that the androgen program of a high UEBP level was completely and stably formed after androgen action in hepatocytes of ovariectomized females and was fully transferred to daughter cells during hepatocyte proliferation. However experimentally formed androgen program of a high UEBP level in female hepatocytes was completely revealed only during early steps of liver regeneration (the 4th day), its expression was essentially declined after regeneration process was over.  相似文献   
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史若楠  武琳蓓 《黑龙江医学》2021,45(20):2229-2231
目的:基于批判性思维的综合护理在老年冠心病合并高血压患者中的应用评价.方法:选取2018年11月—2020年1月于河南科技大学第一附属医院就诊住院的92例冠心病合并高血压老年患者,按随机数表法分为观察组和对照组,每组各46例.对照组予以常规干预护理,观察组应用基于批判性思维的综合护理模式干预.观察两组情绪变化、血压变化及治疗依从性.结果:干预后,观察组负性情绪评分均低于对照组(P<0.05);观察组血压控制情况优于对照组(P<0.05);观察组治疗依从性高于对照组(P<0.05).结论:基于批判性思维的综合护理干预可减轻老年冠心病合并高血压患者的负性情绪影响,患者血压控制更理想,治疗依从性更高.  相似文献   
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A copper-based metal–organic framework (MOF) was prepared using a new linker, a 5-substituted isophthalic acid bearing a propargyl carbamate group, intended to provide a terminal alkyne function protruding from the material surface to generate supported gold species for potential catalytic applications. The novel material was fully characterized by spectroscopic analyses of different kinds: FTIR, Raman, EDX, and XPS, as well as by thermal and surface area measurements. Synchrotron X-ray diffraction data analysis, in particular, revealed that this MOF, labelled [Cu(1,3-YBDC)]·xH2O (x ∼ 2), where Y stands for the pendant alkYne and BDC for benzene dicarboxylate, contains a complex network of 5-substituted isophthalate anions bound to Cu(ii) centers, arranged in pairs within paddlewheel (or “Chinese lantern”) fragments of Cu2(μ-COO)4(D)2 formulation (D being a neutral Lewis base), with a short Cu⋯Cu distance of 2.633(4) Å. Quite unexpectedly, the apical atom in the paddlewheel structure belongs to the carbamate carbonyl oxygen atom. Such extra coordination by the propargyl carbamate groups drastically reduces the MOF porosity, a feature that was also confirmed by BET measurements. However, the MOF functionality is retained at the external crystal surface where 2% of active terminal alkynes is located.

A copper-based metal–organic framework with a novel 5-substituted isophthalic linker bearing a propargyl carbamate group protruding from the material surface.  相似文献   
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Multiple sclerosis: serial study of gadolinium-enhanced MR imaging   总被引:4,自引:0,他引:4  
Thirteen patients with definite multiple sclerosis (MS), studied 16-24 months previously with magnetic resonance (MR) imaging with and without enhancement by intravenously administered gadolinium diethylenetriaminepentaacetic acid (DTPA) dimeglumine, were reexamined with a similar protocol. Assessment of enhancement and clinical activity in both studies revealed that enhancement was observed in 13 of 14 cases in which clinical activity had changed within 4 weeks of the study and thus appeared more sensitive than clinical examination in determining active disease. The 3-minute postinjection, short repetition time image (TR) was the most efficient for depicting enhancement. Enhancing lesions (active plaques) arose from previously hyper- or isointense regions on long TR images. Previously active lesions reverted to areas of iso- or hyperintensity on long TR images. Serial comparison of long TR images in this population reveals a decrease in high-intensity lesions on long TR images in some cases and an increase in others. The findings of high-intensity regions on long TR images and previously enhancing lesions both becoming isointense suggests that transient inflammatory changes with concomitant edema without demyelination and/or with significant remyelination may occur in some MS lesions. MS lesions are dynamic; both active and inactive lesions may show dramatic change on longitudinal MR imaging studies.  相似文献   
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