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31.
Amparo Castillo-Richmond MD Charles N. Alexander PhD Hector Myers PhD Vidya Kaushik MD Cesar Aranguri MD 《Behavioral medicine (Washington, D.C.)》2013,39(2):83-95
Abstract African Americans experience higher morbidity and mortality than Whites do as a result of hypertension and associated cardiovascular disease. Chronic psychosocial stress has been considered an important contributing factor to these high rates. The authors describe the rationale and design for a planned randomized controlled trial comparing Transcendental Meditation, a stress-reduction technique, with lifestyle education in the treatment of hypertension and hypertensive heart disease in urban African Americans. They pretested 170 men and women aged 20 to 70 years over a 3-session baseline period, with posttests at 6 months. Outcomes included clinic and ambulatory blood pressure, quality of life, left ventricular mass measured by M-mode echocardiography, left ventricular diastolic function measured by Doppler, and carotid atherosclerosis measured by β-mode ultrasound. This trial was designed to evaluate the hypothesis that a selected stress reduction technique is effective in reducing hypertension and hypertensive heart disease in African Americans. 相似文献
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Wu WX Ma XH Coksaygan T Chakrabarty K Collins V Rose J Nathanielsz PW 《Endocrinology》2004,145(3):1444-1452
The experiments reported here were designed for both in vivo and in vitro approaches in the same animals to obtain a better picture of the role of estrogen in the control of parturition. Chronically catheterized pregnant ewes were treated with vehicle (n = 5) or estradiol (n = 6), 5 mg twice a day, im for 2 d starting at d 119 of gestation. Maternal and fetal plasma estradiol, progesterone, and cortisol were measured by RIA and maternal plasma prostaglandin (PG) F2alpha was measured by enzyme immunoassay. Intrauterine PG H synthase 2 mRNA and protein and placental P450(c17)alpha hydroxylase mRNA were determined by Northern, in situ hybridization, Western blot analysis, and immunocytochemistry. Data were analyzed by ANOVA.Five of six estradiol-treated ewes delivered their fetuses within 48 h; however, the placenta was still retained 5-6 h after fetal delivery. Both maternal plasma estradiol and PGF2 alpha increased significantly in the estradiol-treated group. Maternal and fetal plasma progesterone and cortisol were not altered in either group. There were significant increases of PGH synthase 2 mRNA and protein in myometrium, endometrium, and maternal placenta but not in fetal placenta in estradiol-treated ewes. Placental P450(c17)alpha hydroxylase mRNA was not detectable in vehicle or estradiol-treated groups.Estradiol can, in the absence of increase in plasma cortisol, stimulate uterine PG production and induce labor, resulting in fetal delivery in the sheep. Failure of placental delivery after estradiol treatment suggests that estradiol alone is insufficient to stimulate some of the key changes required to complete delivery at the stage of gestation studied. 相似文献
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Amarnath R. Allu Sathravada Balaji Kavya Illath Chaithanya Hareendran T. G. Ajithkumar Kaushik Biswas K. Annapurna 《RSC advances》2018,8(26):14422
Understanding the conductivity variations induced by compositional changes in sodium super ionic conducting (NASICON) glass materials is highly relevant for applications such as solid electrolytes for sodium (Na) ion batteries. In the research reported in this paper, NASICON-based NCAP glass (Na2.8Ca0.1Al2P3O12) was selected as the parent glass. The present study demonstrates the changes in the Na+ ion conductivity of NCAP bulk glass with the substitution of boron (NCABP: Na2.8Ca0.1Al2B0.5P2.7O12) and gallium (NCAGP: Na2.8Ca0.1Al2Ga0.5P2.7O12) for phosphorus and the resulting structural variations found in the glass network. For a detailed structural analysis of NCAP, NCABP and NCAGP glasses, micro-Raman and magic angle spinning-nuclear magnetic resonance (MAS-NMR) spectroscopic techniques (for 31P, 27Al, 23Na, 11B and 71Ga nuclei) were used. The Raman spectrum revealed that the NCAP glass structure is more analogous to the AlPO4 mesoporous glass structure. The 31P MAS-NMR spectrum illustrated that the NCAP glass structure consists of a high concentration of Q0 (3Al) units, followed by Q0 (2Al) units. The 27Al MAS-NMR spectrum indicates that alumina exists at five different sites, which include AlO4 units surrounded by AlO6 units, Al(OP)4, Al(OP)5, Al(OAl)6 and Al(OP)6, in the NCAP glass structure. The 31P, 27Al and 11B MAS-NMR spectra of the NCABP glass revealed the absence of B–O–Al linkages and the presence of B3–O–B4–O–P4 linkages which further leads to the formation of borate and borophosphate domains. The 71Ga MAS-NMR spectrum suggests that gallium cations in the NCAGP glass compete with the alumina cations and occupy four (GaO4), five (GaO5) and six (GaO6) coordinated sites. The Raman spectrum of NCAGP glass indicates that sodium cations have also been substituted by gallium cations in the NCAP glass structure. From impedance analysis, the dc conductivity of the NCAP glass (∼3.13 × 10−8 S cm−1) is slightly decreased with the substitution of gallium (∼2.27 × 10−8 S cm−1) but considerably decreased with the substitution of boron (∼1.46 × 10−8 S cm−1). The variation in the conductivity values are described based on the structural changes of NCAP glass with the substitution of gallium and boron.Understanding the conductivity variations induced by compositional changes in sodium super ionic conducting (NASICON) glass materials is highly relevant for applications such as solid electrolytes for sodium (Na) ion batteries. 相似文献
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Objectives. We investigated the development of and service utilization at Supporting Positive Opportunities with Teens (SPOT)—a community-based health and social service facility in St. Louis, Missouri, for youths that focuses on increasing HIV and sexually transmitted infection (STI) testing.Methods. We identified the US-based, co-located youth health and social service models that guided the establishment of the SPOT. We analyzed the first 5 years (2008–2013) of service delivery and utilization data.Results. During the study period, the SPOT provided services for 8233 youths in 37 480 visits. The 5 most utilized services included HIV and STI screening, food, transportation, contraception, and case management. A total of 9812 gonorrhea and chlamydia screenings revealed 1379 (14.1%) cases of chlamydia and 437 (4.5%) cases of gonorrhea, and 5703 HIV tests revealed 59 HIV infections (1.0%); 93.0% of patients found to have an STI were treated within a 5-day window.Conclusions. Co-locating health and social services in informal community settings attracts high-risk youths to utilize services and can prove instrumental in reducing STI burden in this population.Sexual behaviors that contribute to unintended pregnancy and sexually transmitted infections (STIs), including HIV, are considered a priority health-risk behavior among youths in the United States.1 In 2008, St. Louis, Missouri, had some of the highest rates of Neisseria gonorrheae and Chlamydia trachomatis infections of all US cities.2 The majority of STIs in youths aged 15 to 24 years in Missouri are seen disproportionately among African American youths. HIV infection rates among youths continue to rise.3 From 2008 to 2010 new cases of HIV/AIDS among male youths in St. Louis increased by 33%, compared with a 2% increase among adult males.3,4These high rates of STIs and HIV highlight gaps in services for youths in our region. Evidence suggests that it is best to co-locate health and social services when providing care to a very needy population of youths.5–7 There are programs that do this in multiple sites across the country. Studies found that peer-to-peer information sharing and outreach, peer advisory groups, tightly linked medical and social services, and active case management to assess need and link youths to services were critical for keeping youths engaged.6,7 Despite the obvious needs of youths in St. Louis, no social service agency or health facility has ever combined these services for youths aged 13 to 24 years.We describe the development of our youth center, the SPOT (Supporting Positive Opportunities with Teens), and report screening outcomes and service utilization measures for the first 5 years of the center. We focus on identifying STI and HIV infections in youths and ensuring access to timely treatment. 相似文献
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Gaurav Bajpai Tulika Srivastava N. Patra Igamcha Moirangthem S. N. Jha D. Bhattacharyya Sk Riyajuddin Kaushik Ghosh Dharma R. Basaula Mahmud Khan Shun-Wei Liu Sajal Biring Somaditya Sen 《RSC advances》2018,8(43):24355
Substituting an ion of different size from that of the host element introduces lattice strain and defects. However, this mismatch may be significantly reduced by substituting an additional ion with a compensating size relative to the dopant. Such a double substitution might offer better solubility irrespective of the local distortions as well as the formation of defects in the valence states. Fe-substituted ZnO has been widely reported with conflicting results primarily arising from lack of chemical and structural homogeneity originating from preparation techniques, compositional fluctuations, and equivocal comprehension of actual solubility limits of the dopants. In this study, Ag ion has been incorporated in Fe-substituted ZnO to compensate the ionic size of Zn1−x[Fe0.8Ag0.2]xO (0 ≤ x ≤ 0.03125) by determining the solubility limit of the homogeneous material and their corresponding structural, mechanical, optical and magnetic properties have been investigated thoroughly. Co-substitution rearranges the lattice and leads to better crystal structures with tunable properties related to the amount of substitution.Substituting an ion of different size from that of the host element introduces lattice strain and defects. 相似文献
40.
Eastin Jennifer Dey Dzifa Amissah-Arthur Maame-Boatemaa Chaudhuri Kaushik Jawad Ali 《Clinical rheumatology》2021,40(9):3439-3443
Clinical Rheumatology - A project aimed to develop and deliver a clinical training course in Accra, Ghana, to increase patient access to physicians trained in the diagnosis, treatment and... 相似文献