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Eun-Ok Im Young Ko Hyenam Hwang Wonshik Chee 《Health care for women international》2013,34(6):575-592
Our purpose in this study was to identify differences in menopausal symptom management among four major ethnic groups in the United States. This was a secondary analysis of the qualitative data from a larger Internet-based study. We analyzed data from 90 middle-aged women in the United States using thematic analysis. We extracted four themes during the data analysis process: (a) “seeking formal or informal advice,” (b) “medication as the first or final choice,” (c) “symptom-specific or holistic,” and (d) “avoiding or pursuing specific foods.” Health care providers need to develop menopausal symptom management programs while considering ethnic differences in menopausal symptom management. 相似文献
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Ming Zhou Haomin Song Xingyu Xu Alireza Shahsafi Yurui Qu Zhenyang Xia Zhenqiang Ma Mikhail A. Kats Jia Zhu Boon S. Ooi Qiaoqiang Gan Zongfu Yu 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(14)
A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.Energy and clean water are global challenges that are intertwined in an unfavorable way: even in areas where water is abundant, energy may not be available to purify it for human use (1, 2). There has been strong interest in developing passive technologies to purify or harvest water without using fuel or electricity. In this context, passive vapor condensation becomes particularly important because many passive water technologies go through the vapor phase of water in their harvesting or purification processes.Traditional vapor condensation technique is based on convective and conductive heat exchange with ambient environments. This technique is widely used in systems with hot vapors (3–6). However, with ever-increasing emphasis on passive systems, there are many situations in which warm- or even room-temperature vapor needs to be effectively condensed, such as extracting water from atmosphere (7–9) and warm vapor generated from high-efficiency solar evaporation (10). For vapor at such temperatures, most traditional condensers fail. For this reason, there is a clear need for a condensation technique to complement traditional condensers.A different technique is based on radiative vapor condensation. Darkling beetles in the Namib desert (11) use this technique to collect water. Their bodies function as a cooling surface by shedding thermal energy through midinfrared (mid-IR) radiation toward a clear nighttime sky, generating dew from humid air. This mechanism is also used by commercial radiative dew condensers (7–9). However, neither Namib beetle nor existing dew condensers can operate in the daytime (7). Those nighttime radiative condensers are incompatible with many emerging water technologies that require 24 h operation or direct access to sunlight.Recently, Fan et al. showed that passive radiative cooling to subambient temperatures can be realized even during the daytime, by integrating a high-efficiency solar reflector with a high-emissivity thermal emitter in the mid-IR atmospheric transparency window (12). Using this work as a basis, here we demonstrate a daytime radiative condenser. Compared to existing radiative vapor condensers (7–9), our condenser can function even in the presence of sunlight, which is essential for integration into passive water-harvesting systems that mainly operate during daytime. 相似文献
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Computed tomographic evaluation of the role of craniofacial and upper airway morphology in obstructive sleep apnea in Chinese 总被引:5,自引:0,他引:5
OBJECTIVES: To evaluate the relationship between cephalometric parameters, upper airway morphological factors and obstructive sleep apnea (OSA) in Chinese subjects. DESIGN: Polysomnogram (PSG) were performed and scored using standard criteria. Supine lateral cephalometric parameters and pharyngeal cross-sectional areas at the level of velopharynx (VA) and hypopharynx (HA) were measured from computed tomographic scans. The roles of these parameters and other anthropometric/demographic characteristics in OSA (apnea hypopnea index, AHI > or = 5) and their relationship with severity of OSA were explored by multiple logistic and multinominal regression analysis. RESULTS: Ninety-two subjects, ranging from normal (n = 36), mild/moderate OSA (n = 34) to severe OSA (n = 22), were evaluated. Compared with normal subjects, OSA subjects were heavier (body mass index 27 vs. 24 kg/m2) and older (47 vs. 42 years of age); had smaller VA size and VA to HA ratio, lower positioned hyoid bone, longer and thicker soft palate, and more retropositioned mandible relative to maxilla. After controlling for body mass index and age, subjects with severe OSA (AHI > 30) had more retropositioned mandible relative to maxilla (odds ratio, OR 1.31, P = 0.044) and longer soft palate (OR 1.16, P = 0.01), while those with mild/moderate OSA had larger VA to HA ratio (OR 0.17, P = 0.018). CONCLUSIONS: Craniofacial factors and upper airway morphology contributed to severity of OSA in Chinese subjects. Having controlled for obesity, more retropositioned mandible was associated with more severe OSA. 相似文献
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In Ae Kim Hyun Suk Yang Wan Seop Kim Hyun Keun Chee 《Journal of Korean medical science》2015,30(9):1367-1372
Fulminant myocarditis has been defined as the clinical manifestation of cardiac inflammation with rapid-onset heart failure and cardiogenic shock. We report on the case of a 23-yr-old woman with pathology-proven fulminant lymphocytic myocarditis presenting shock with elevated cardiac troponin I and ST segments in V1-2, following sustained ventricular tachycardia and a complete atrioventricular block. About 55 min of intensive cardio-pulmonary resuscitation, with extracorporeal membrane oxygenation support, bridged the patient to orthotopic heart transplantation. The explanted heart revealed diffuse lymphocytic infiltration and myocyte necrosis in all four cardiac chamber walls. Aggressive mechanical circulatory support may be an essential bridge for recovery or even transplantation in patients with fulminant myocarditis with shock.
Graphical Abstract
相似文献69.
P L Ho P H Chau P S F Yip G C Ooi P L Khong J C Ho P C Wong C Ko C Yan K W Tsang 《The European respiratory journal》2005,26(3):474-479
A prospective study was undertaken to identify clinical, radiographical, haematological and biochemical profiles of severe acute respiratory syndrome (SARS) patients. A prediction rule, which demarcates low from high risk patients for SARS in an outbreak situation was developed. A total of 295 patients with unexplained respiratory illnesses, admitted to Queen Mary Hospital, Hong Kong SAR, China, in March to July 2003, were evaluated for clinical, radiological, haematological and alanine transaminase (ALT) data daily for 3 days after hospitalisation. In total, 44 cases were subsequently confirmed to have SARS by RT-PCR (68.2%) and serology (100%). The scoring system of attributing 11, 10, 3, 3 and 3 points to the presence of independent risk factors, namely: epidemiological link, radiographical deterioration, myalgia, lymphopenia and elevated ALT respectively, generated high and low-risk (total score 11-30 and 0-10, respectively) groups for SARS. The sensitivity and specificity of this prediction rule in positively identifying a SARS patient were 97.7 and 81.3%, respectively. The positive and negative predictive values were 47.8 and 99.5%, respectively. The prediction rule appears to be helpful in assessing suspected patients with severe acute respiratory syndrome at the bedside, and should be further validated in other severe acute respiratory syndrome cohorts. 相似文献
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Vascular load is an important determinant of ventricular function. This is particularly true of the failing heart, which is exquisitely load-sensitive. Vascular load comprises 2 major components: resistive load, which arises primarily at the arteriolar resistance vessels, and pulsatile load, which is primarily determined by aortic stiffness and early return of reflected waves from the periphery to the heart. Assessment of pulsatile load is gaining increasing prominence as evidence grows of a significant pathophysiologic role for arterial stiffness in cardiovascular disease, including heart failure. Assessment of arterial stiffness and vascular load is reviewed here. The importance of optimal ventricular-vascular coupling to maximize the efficiency of cardiac ejection is discussed. Current knowledge of arterial stiffness, vascular load, and ventricular-vascular coupling in systolic heart failure and in heart failure with a normal ejection fraction ("diastolic failure") is described. Reducing aortic stiffness may form an important future therapeutic target in patients with heart failure. 相似文献