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81.
Gichane Margaret W. Rosenberg Nora E. Zimmer Catherine Pettifor Audrey E. Maman Suzanne Maseko Bertha Moracco Kathryn E. 《AIDS and behavior》2022,26(3):822-832
AIDS and Behavior - Transactional sex increases HIV risk among adolescent girls and young women (AGYW). Understanding the individual and dyadic nature of transactional sex may provide evidence for... 相似文献
82.
Abstract. Red blood cells (RBC) were collected with citrate-phosphate-dextrose (CPD) in a blood-pack optimal additive system. After concentration to 90% hematocrit they were diluted with saline-adenine-glucose medium (SAG-RBC), and stored for 35 days. In this work the RBC were stored in the presence of leukocytes. The SAG medium allows RBC conservation during 35 days at +4°C. The adenosine triphosphate (ATP) level of RBC is compatible with their survival. During the first 2 weeks, hemolysis of SAG-RBC was not greater than in CPD blood. Nevertheless, hemolysis reached 1.49% on day 35, and there was a marked increase in RBC osmotic fragility. Scanning electron-microscopic studies of 35-day RBC showed that the majority of them became echinocytes. After incubation in fresh frozen plasma, the RBC recovered satisfactory osmotic resistance and normal disc shape. The post-transfusion viability was normal with >70% recovery after 48 h. The in vivo restoration of 2,3-diphosphoglycerate (2,3-DPG) was rapid in the transfused SAG-RBC, 50% of the initial 2,3-DPG level being restored in 1 h. The in vivo studies proved that the functional quality of these RBC was compatible with their use in transfusion. The most important problem concerns the supernatant hemoglobin level of the SAG-RBC to be used for massive transfusion. 相似文献
83.
Audrey Dionne Anne Fournier Nagib Dahdah Dominic Abrams Paul Khairy Sylvia Abadir 《The Canadian journal of cardiology》2018,34(1):66-72
Background
QT-interval variations in response to exercise-induced increases in heart rate have been reported in children and adults in the diagnosis of long QT syndrome (LQTS). A quick standing challenge has been proposed as an alternative provocative test in adults, with no pediatric data yet available.Methods
A standing test was performed in 100 healthy children (mean age, 9.7 ± 3.1 years) after 10 minutes in a supine position with continuous electrocardiographic recording. QT intervals were measured at baseline, at maximal heart rate, at maximal QT, and at each minute of a 5-minute recovery while standing. Measurements were taken in leads II/V5 and were corrected for heart rate (QTc).Results
On standing, the heart rate increased by 29 ± 10 beats per minute (bpm). The QT interval was similar at baseline and on standing (394 ± 34 ms vs 394 ± 34 ms; P = 1.0). However, QTc increased from 426 ± 21 to 509 ± 41 ms (P < 0.001). The 95th percentile for QTc at baseline and maximal heart rate was 457 ms and 563 ms, respectively. At 1 minute of recovery, the QT interval was shorter (375 ± 31 ms) compared with baseline (394 ± 34 ms; P < 0.001) and standing (394 ± 34 ms; P < 0.001). QTc reached baseline values after 1 minute of recovery and remained stable thereafter (423 ± 23 ms at 1 minute; 426 ± 22 ms at 5 minutes; P = 1.0).Conclusions
This first characterization of QTc changes on standing in children shows substantial alterations, which are greater than those seen in adults. Two-thirds of the children would have been misclassified as having LQTS by adult criteria, indicating the need to create child-specific standards. 相似文献84.
Karen B. Basham Sarah P. Whitmore Audrey F. Adcock Patricia V. Basta 《Alcoholism, clinical and experimental research》1998,22(7):1501-1508
The overall objective of this study was to analyze the effects of a combined prenatal and postnatal (entire gestational human chronic drinking model) ethanol exposure on T-cell development in mice. Specifically, this study evaluated the effects of chronic exposure to prenatal ethanol on lymphocyte makeup and proliferative capabilities of postnatal offspring's (4 and 12 weeks) peripheral lymphoid tissues. Chronic exposure regimens were conducted over the entire gestational period and through postnatal day 14 or 21. Thymus, spleen, and intestinal intraepithelial lymphocytes were harvested and analyzed by flow cytometry for percentages of T-cell subsets. Splenic lymphocytes were also analyzed for their ability to proliferate in response to a T-cell mitogen. Limited effects of chronic ethanol exposure were seen. 相似文献
85.
86.
Cyclic neutropenia is a rare hematologic disorder, characterized by repetitive episodes of fever, mouth ulcers, and infections attributable to recurrent severe neutropenia. Fluctuations in blood cells are due to oscillatory production of cells by the bone marrow. Recent genetic, molecular, and cellular studies have shown that autosomal-dominant cyclic neutropenia and sporadic cases of this disease are due to a mutation in the gene for neutrophil elastase (ELA2), located at 19p13.3. This enzyme is synthesized in neutrophil precursors early in the process of primary granule formation. It is currently presumed that the mutant neutrophil elastase functions aberrantly within the cells to accelerate apoptosis of the precursors, resulting in effective and oscillatory production. Cyclic neutropenia is effectively treated with granulocyte colony-stimulating factor (G-CSF), usually at doses of 1 to 5 microg/kg/d (median dose, 2.5 microg/kg/d). Long-term, daily, or alternate-day administration reduces fever, mouth ulcers, and other inflammatory events associated with this disorder. Leukemic transformation is not a recognized risk for cyclic neutropenia, with or without treatment with G-CSF. 相似文献
87.
Pettifor AE Kleinschmidt I Levin J Rees HV MacPhail C Madikizela-Hlongwa L Vermaak K Napier G Stevens W Padian NS 《Tropical medicine & international health : TM & IH》2005,10(10):971-980
OBJECTIVES: To determine whether South African youths living in communities that had either of two youth human immunodeficiency virus (HIV) prevention interventions [(a) loveLife Youth Centre or (b) loveLife National Adolescent Friendly Clinic Initiative] would have a lower prevalence of HIV, sexually transmitted infections (STIs), and high risk sexual behaviours than communities without either of these interventions. METHODS: In 2002 the baseline survey of a quasi-experimental, community-based study was conducted in South Africa. In total 33 communities were included in three study arms (11 communities per study arm). The final sample included 8735 youths aged 15-24 years. All participants took part in a behavioural interview and were tested for HIV, gonorrhoea (Neisseria gonorrhoeae) and Chlamydia (Chlamydia trachomatis). RESULTS: HIV prevalence was 20.0% among females and 7.5% among males (OR 3.93 95% CI 2.51-6.15). There were no significant differences between study arms for HIV, NG or CT prevalence at baseline. In multiple regression analyses, HIV was significantly associated with NG infection (OR 1.96 95% CI 1.24-3.12) but not with CT infection. Youths who reported >1 lifetime partner were also significantly more likely to be infected with HIV (OR 1.98 95% CI 1.55-2.52), as were those who reported ever having engaged in transactional sex (OR 1.86 P = 0.02) or having had genital ulcers in the past 12 months (OR 1.71 P < or = 0.001). CONCLUSIONS: HIV prevention programmes must ensure that gender inequities that place young women at greater risk for HIV infection are urgently addressed and they must continue to emphasize the importance of reducing the number of sexual partners and STI treatment. 相似文献
88.
The evolution of instrumentation in terms of separation and detection allowed a real improvement of the sensitivity and analysis time. However, the analysis of ultra-traces of toxins in complex samples requires often a step of purification and even preconcentration before their chromatographic analysis. Therefore, immunoaffinity sorbents based on specific antibodies thus providing a molecular recognition mechanism appear as powerful tools for the selective extraction of a target molecule and its structural analogs to obtain more reliable and sensitive quantitative analysis in environmental, food or biological matrices. This review focuses on immunosorbents that have proven their efficiency in selectively extracting various types of toxins of various sizes (from small mycotoxins to large proteins) and physicochemical properties. Immunosorbents are now commercially available, and their use has been validated for numerous applications. The wide variety of samples to be analyzed, as well as extraction conditions and their impact on extraction yields, is discussed. In addition, their potential for purification and thus suppression of matrix effects, responsible for quantification problems especially in mass spectrometry, is presented. Due to their similar properties, molecularly imprinted polymers and aptamer-based sorbents that appear to be an interesting alternative to antibodies are also briefly addressed by comparing their potential with that of immunosorbents. 相似文献
89.
Audrey Duarte Patricia Hearons Yashu Jiang Mary Courtney Delvin Rachel N. Newsome Paul Verhaeghen 《Psychophysiology》2013,50(5):465-476
Behavioral evidence from the young suggests spatial cues that orient attention toward task‐relevant items in visual working memory (VWM) enhance memory capacity. Whether older adults can also use retrospective cues (“retro‐cues”) to enhance VWM capacity is unknown. In the current event‐related potential (ERP) study, young and old adults performed a VWM task in which spatially informative retro‐cues were presented during maintenance. Young but not older adults' VWM capacity benefited from retro‐cueing. The contralateral delay activity (CDA) ERP index of VWM maintenance was attenuated after the retro‐cue, which effectively reduced the impact of memory load. CDA amplitudes were reduced prior to retro‐cue onset in the old only. Despite a preserved ability to delete items from VWM, older adults may be less able to use retrospective attention to enhance memory capacity when expectancy of impending spatial cues disrupts effective VWM maintenance. 相似文献
90.
Philippe Halfon Maria Luisa Mateos Lindemann Audrey Raimondo Sophie Ravet Claire Camus Hacène Khiri Guillaume Pénaranda Mario Sideri Maria Teresa Sandri 《Archives of virology》2013,158(6):1143-1149
A new genotyping-based DNA assay (Digene LQ®) was developed recently. The primary aim was to assess the distribution of HPV types using this new assay in atypical squamous cells of undeterminate significance (ASCUS). The secondary aim was to correlate the HPV types with the severity of the disease. The study population comprised 376 ASCUS women. The women were all Hybrid Capture II (HCII) positive and were admitted in three European referral gynecology clinics between 2007 and 2010. A colposcopy with histological examination was performed in all these patients. HPV 16 was typed in 40 % of patients, HPV 18 in 7 %, and HPV 31 in 17 %, and 18 % of patients had mixed genotypes. Patients aged over 30 more often had the HPV 16 genotype than patients aged under 30 (29 % vs. 11 %, chi-square test p < 0.001). The risk of cervical intra-epithelial neoplasia of grade 2 or more (CIN2 +) when HPV 18 positive is lower than the probability associated with HPV 16 or HPV 31: 28 % vs. 58 % and 52 %, respectively (chi-square test, p = 0.005 and p = 0.05, respectively). The Digene LQ®, a new sequence-specific hybrid capture sample preparation, is fast and efficient and allows high-throughput genotyping of 18 HR HPV types by PCR compared to traditional non-sequence-specific sample preparation methods. 相似文献