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排序方式: 共有451条查询结果,搜索用时 15 毫秒
1.
Perla A Vargas Pippa M Simpson Margo Bushmiaer Rajiv Goel Craig A Jones James S Magee Charles R Feild Stacie M Jones 《Annals of allergy, asthma & immunology》2006,96(6):787-793
BACKGROUND: Children with poorly controlled asthma are at high risk of airway remodeling, sleep disruption, school absenteeism, and limited participation in activities. OBJECTIVE: To determine asthma prevalence and characterize disease severity and burden in school-aged children. METHOD: A case-finding study was conducted via a multiple-choice questionnaire and asthma algorithm. Items used for analysis include physician diagnosis of asthma, symptom severity, and health care utilization. The chi2 test was used to determine the significance of differences among cases. Logistic regression was used to evaluate the association of patient factors and asthma indicators. RESULTS: Of the 5,417 children surveyed, 1,341 (25%) were classified as being at risk of asthma. Of these asthma cases, 55% were positive by diagnosis and algorithm (active), 10% were positive per algorithm alone (suspected), and 35% were positive per diagnosis alone (nonactive). Only 14% of all asthma cases reported experiencing no respiratory symptoms (< 1% active, 2% suspected, and 40% nonactive) compared with 75% of noncases. Also, 75% of noncases reported never missing school compared with 19%, 33%, and 54% of active, suspected, and nonactive asthma cases. African American race, Medicaid enrollment, and male sex were independent predictors of asthma risk. Similarly, African American race, Medicaid enrollment, age, and persistent asthma were independent predictors of emergency department use among asthma cases. DISCUSSION: Prevalence of active symptoms suggestive of poor asthma control was extremely high among urban, minority children enrolled in Arkansas' largest public school district. Poor asthma control greatly affects quality of life, including school attendance and performance. Interventions should raise expectations and emphasize the importance of achieving asthma control. 相似文献
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3.
Tamara T Perry Perla A Vargas Jeremy Bufford Charles Feild Michael Flick Pippa M Simpson Robert G Hamilton Stacie M Jones 《Annals of allergy, asthma & immunology》2008,100(4):358-363
BACKGROUND: The impact of preschool environmental conditions on classroom aeroallergen concentrations is not fully understood. OBJECTIVE: To examine the relationship between school environmental conditions and classroom aeroallergen concentrations in the Pulaski County Head Start (HS) Program. METHODS: Thirty-three HS centers in Pulaski County, Arkansas, underwent a detailed environmental evaluation. Classroom settled dust samples were analyzed for the presence of common indoor allergens. RESULTS: Classroom eating (70%), wall-to-wall carpeting (58%), and water damage (33%) were common. Median classroom allergen levels were as follows: dust mite (Der p 1 and Der f 1), 0.6 microg/g; Fel d 1, 0.4 microg/g; Can f 1, 1.7 microg/g; cockroach, below detection; Mus m 1, 0.18 microg/g; and mold spores, 17,800 CFU/g. Can f 1 and Mus m 1 allergens were detected in 100% of HS centers. Facilities with carpeting, increased humidity, and single-use facilities showed trends toward increased dust mite concentrations. Detectable cockroach allergen was more common in classrooms cleaned by teachers than by professional housekeepers. CONCLUSIONS: Aeroallergens were commonly detected in Pulaski County HS center classrooms, with dog and mouse allergens detected in 100% of centers. Median classroom allergen concentrations were low, and classroom characteristics were not strongly predictive of increased allergen exposure. 相似文献
4.
Judith K. Brown Perla Subbaiah Therese Sarah 《Journal of cross-cultural gerontology》1994,9(2):231-254
Our cross-cultural study of the relationship between older women and their younger female kin examines women's hierarchies based on age and focuses on the exercise of authority by women, when such authority is traditional and accepted. Data were collected for two world-wide samples each consisting of 30 societies, varying in complexity, subsistence base, geographic location, and in customs related to women's lives. Three hypotheses were tested. The findings, which are statistically significant, suggest that the relationships between older women and their younger female kin are patterned and predictable, determined by the role of women in subsistence activities, by rules for post-marital residence, and by descent.When domination can only be exercised... directly, between one person and another, it can not take place overtly and must be disguised under the veil of enchanted relationships, the official model of which is presented by the relations between kinsmen.The gentle, invisible form of violence, which is never recognized as such... can not fail to be seen as the most economical mode of domination...The system is such that the dominant agents have a vested interest in virtue. (Bourdieu 1991191, 192, 194) 相似文献
5.
Sonia Galván-Arzate José Pedraza-Chaverrí Omar N Medina-Campos Perla D Maldonado Beatriz Vázquez-Román Camilo Ríos Abel Santamaría 《Food and chemical toxicology》2005,43(7):1037-1045
Thallium (Tl+) toxicity has been related with the generation of reactive oxygen species (ROS) and oxidative stress (OS) in the central nervous system. Since changes in endogenous antioxidant systems might contribute to acute Tl+-induced OS and neurotoxicity, in this study we measured the metal concentration and the levels of lipid peroxidation (LP) in different brain regions (hypothalamus (Ht); cerebellum (Ce); striatum (S); hippocampus (Hc) and frontal cortex (Cx)) in possible correlation with the content of reduced glutathione (GSH), the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD), and the animal performance in behavioral tests, all evaluated after a single administration of thallium acetate (8 or 16 mg/kg, i.p.) to rats. Seven days after Tl+ administration, the metal was homogeneously and dose-dependently accumulated in all regions evaluated. LP was increased in Ht, Ce and S, while GSH was depleted in S. Cu,Zn-SOD activity was also decreased in Ht and S. All these changes occurred with 16 mg/kg dose and at 7 days after treatment, but not at 1 or 3 days. In addition, Tl+-treated animals exhibited general hypokinesis, but no changes were observed in spatial learning. Our findings suggest that a delayed response of the brain to Tl+ may be the result of its residual levels. Also, despite the regional alterations produced by Tl+ in LP and the limited changes in endogenous antioxidants, there is a correlation between the Tl+-induced oxidative damage and the affected behavioral tasks, suggesting that, although still moderate, Tl+ evokes neurotoxic patterns under the experimental conditions tested. 相似文献
6.
Schmidt AP Lara DR de Faria Maraschin J da Silveira Perla A Onofre Souza D 《Brain research》2000,864(1):40-43
In the mammalian CNS, glutamate and GABA are the principal neurotransmitters mediating excitatory and inhibitory synaptic events, respectively, and have been implicated in the neurobiology of seizures. Guanine-based purines, including the nucleoside guanosine and the nucleotide GMP, have been shown to antagonize glutamatergic activity at the receptor level and the other purine nucleoside adenosine is a well-known modulator of seizure threshold. In the present study we investigated the anticonvulsant effect of i. p. guanosine and GMP against seizures induced by the glutamate agonist quinolinic acid (QA) or the GABA(A) antagonist picrotoxin in mice. Animals were pretreated with an i.p. injection of saline, guanosine or GMP 30 min before either an i.c.v. injection of 4 microliter QA (36.8 nmol) or a subcutaneous injection of picrotoxin (3.2 mg/kg). All animals pretreated with vehicle followed by QA or picrotoxin presented seizures, which were completely prevented by the NMDA antagonist MK-801 and the GABA agonist phenobarbital, respectively. Guanosine and GMP dose-dependently protected against QA-induced seizures, up to 70 and 80% at 7.5 mg/kg, with ED(50)=2. 6+/-0.4 and 1.7+/-0.6 mg/kg, respectively. Conversely, neither guanosine, GMP nor MK-801 affected picrotoxin-induced seizures, indicating some degree of specificity towards the glutamatergic system. This study suggests anticonvulsant properties of i.p. guanosine and GMP, which may be related with antagonism of glutamate receptors. 相似文献
7.
IB de Groot AM Stiggelbout PJ van der Boog AG Baranski PJ Marang-van de Mheen;for the PARTNER-study group 《Transplant international》2012,25(9):967-975
Health related quality of life (HRQoL) of living kidney donors on average is good, but some donors experience a low HRQoL after donation. This study assessed the prevalence of reduced HRQoL and explored associations with pre‐ and post‐donation variables. 316 donors (response rate 74%) who donated a kidney between 1997 and 2009 filled in a questionnaire. HRQoL was measured using the Short‐Form 36; fatigue using the Multidimensional Fatigue Inventory; societal participation using the Utrecht Scale for Evaluation of Rehabilitation‐Participation. Donors on average had better HRQoL than the general population. However, 12% had a reduced physical (PCS) and 18% a reduced mental (MCS) HRQoL. Donors with reduced HRQoL reported greater fatigue (P < 0.01), lower societal participation (P < 0.01) and showed a trend towards statistical significance in experiencing more donor–recipient relationship changes (P = 0.07). Prior to donation, donors with reduced PCS had a higher BMI (P < 0.05) and more often smoked (P < 0.05). Donors with reduced MCS had higher expectations (P < 0.05). Reduced HRQoL is associated with higher BMI, smoking and higher expectations prior to donation. These results may be used to develop a screening instrument to select donors at high risk for reduced HRQoL. 相似文献
8.
Amelia Oliveira Dana Warcel Nancy Huntley Perla Eleftheriou John B. Porter 《Hemoglobin》2016,40(2):127-129
A female proband homozygous for both Hb Luton [α89(FG1)His→Leu (CAC>CTC), HBA2: c.269A>T (or HBA1)], a high oxygen affinity hemoglobin (Hb), and for α+-thalassemia (α-thal), (–α4.2, leftward deletion) was first described in 2012. This is a follow-up report of the same case. At the age of 18, the described patient presented with progressively worsening lethargy, headaches, dizziness, syncope and Raynaud’s phenomenon. Following extensive cardiological and neurological investigation, it was felt that significant erythrocytosis was the most likely cause. Venesection followed by regular exchange transfusions were arranged with marked amelioration in symptomatology. In the vast majority of cases of high oxygen affinity Hbs, venesection is not recommended due to the asymptomatic phenotype and reduced oxygen delivery resulting from venesection. This update describes the evolving phenotype of this unique proband and, to the best of our knowledge, the first use of regular, long-term therapeutic red cell exchange transfusions in a case of high affinity Hb. 相似文献
9.
Perla Graciela Rodríguez Gutirrez Juan Ramn Gonzlez García Yolanda Alicia Castillo De Len Juan Rafael Zrate Guerrero María Teresa Magaa Torres 《Journal of clinical laboratory analysis》2021,35(3)
BackgroundOur aims were to describe the first Mexican patient with abetalipoproteinemia and to perform a comparative analysis of biochemical, clinical, and genetic characteristics of 100 cases reported in the literature.MethodsWe performed biochemical and molecular screenings in a Mexican girl with extremely low lipid levels and in her family. Further, we integrated and evaluated the characteristics of the cases with abetalipoproteinemia described in the literature.ResultsOur patient is a six‐year‐old girl who presented vomiting, chronic diarrhea, failure to thrive, malabsorption, acanthocytosis, anemia, transaminases elevation, and extremely low lipid levels. MTTP gene sequencing revealed homozygosity for a novel mutation p.Gly417Valfs*12 (G deletion c.1250). With the analysis of the reported cases, 60 clinical features (14 classical and 46 non‐classical) were observed, being the most common acanthocytosis (57.5%), malabsorption (43.7%), and diarrhea (42.5%); 48.8% of the patients presented only classic clinical features, while the remaining 51.2% developed secondary effects due to a fat‐soluble vitamin deficiency. An odds ratio analysis disclosed that patients diagnosed after 10 years of age have an increased risk for presenting clinical complications (OR = 18.0; 95% CI 6.0‐54.1, p < 0.0001). A great diversity of mutations in MTTP has been observed (n = 76, being the most common p.G865X and p.N139_E140) and some of them with possible residual activity.ConclusionThe first Mexican patient with abetalipoproteinemia presents a novel MTTP mutation p.Gly417Valfs*12. Three factors that could modulate the phenotype in abetalipoproteinemia were identified: age at diagnosis, treatment, and the causal mutation. 相似文献
10.
AndrewJ. Stott Michel C. Maillard Vahri Beaumont David Allcock Omar Aziz Alexander H. Borchers Wesley Blackaby Perla Breccia Gillian Creighton-Gutteridge Alan F. Haughan Rebecca E. Jarvis Christopher A. Luckhurst Kim L. Matthews George McAllister Scott Pollack Elizabeth Saville-Stones Amanda J. Van de Poël Huw D. Vater Julie Vann Rachel Williams Dawn Yates Ignacio Muoz-Sanjun Celia Dominguez 《ACS medicinal chemistry letters》2021,12(3):380
Using an iterative structure–activity relationship driven approach, we identified a CNS-penetrant 5-(trifluoromethyl)-1,2,4-oxadiazole (TFMO, 12) with a pharmacokinetic profile suitable for probing class IIa histone deacetylase (HDAC) inhibition in vivo. Given the lack of understanding of endogenous class IIa HDAC substrates, we developed a surrogate readout to measure compound effects in vivo, by exploiting the >100-fold selectivity compound 12 exhibits over class I/IIb HDACs. We achieved adequate brain exposure with compound 12 in mice to estimate a class I/IIb deacetylation EC50, using class I substrate H4K12 acetylation and global acetylation levels as a pharmacodynamic readout. We observed excellent correlation between the compound 12 in vivo pharmacodynamic response and in vitro class I/IIb cellular activity. Applying the same relationship to class IIa HDAC inhibition, we estimated the compound 12 dose required to inhibit class IIa HDAC activity, for use in preclinical models of Huntington’s disease. 相似文献