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51.
52.
Antidepressant effect on connectivity of the mood-regulating circuit: an FMRI study. 总被引:7,自引:0,他引:7
Amit Anand Yu Li Yang Wang Jingwei Wu Sujuan Gao Lubna Bukhari Vincent P Mathews Andrew Kalnin Mark J Lowe 《Neuropsychopharmacology》2005,30(7):1334-1344
The mechanisms by which antidepressant-induced neurochemical changes lead to physiological changes in brain circuitry and ultimately an antidepressant response remain unclear. This study investigated the effects of sertraline, a selective serotonin reuptake inhibitor antidepressant, on corticolimbic connectivity, using functional magnetic resonance imaging (fMRI). In all, 12 unmedicated unipolar depressed patients and 11 closely matched healthy control subjects completed two fMRI scanning sessions at baseline and after 6 weeks. Depressed patients received treatment with sertraline between the two sessions. During each fMRI session, subjects first completed a conventional block-design experiment. Next, connectivity between cortical and limbic regions was measured using correlations of low-frequency blood oxygen level-dependent (BOLD) fluctuations (LFBF) during continuous exposure to neutral, positive, and negative pictures. At baseline, depressed patients had decreased corticolimbic LFBF correlations compared to healthy subjects during the resting state and on exposure to emotionally valenced pictures. At rest and on exposure to neutral and positive pictures, LFBF correlation between the anterior cingulate cortex and limbic regions was significantly increased in patients after treatment. However, on exposure to negative pictures, corticolimbic LFBF correlations remained decreased in depressed patients. The results of this study are consistent with the hypothesis that antidepressant treatment may increase corticolimbic connectivity, thereby possibly increasing the regulatory influence of cortical mood-regulating regions over limbic regions. 相似文献
53.
蓣知子皂甙IV的结构 总被引:5,自引:1,他引:5
从木通科木通属植物白木通[Akebia trifoliata(Thunb.)Koidz.var.australis(Diels)Rehd]种子的乙醇提取物中以硅胶层析等方法得四种三萜皂甙。其中甙IV是新天然产物,命名为蓣知子皂甙IV(yuzhiziosideIV)。根据化学和光谱分析,确定甙IV的结构为3-O-β-D-吡喃木糖基-(1→2)-a-L-吡喃阿拉伯糖齐墩果酸-28-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖酯甙。另外皂甙B(I)、皂甙C(II)和皂甙D(III)为已知物。这些化合物在白木通种子中均是首次得到。 相似文献
54.
为了寻找毒性低、增敏作用强的乏氧细胞放射增敏剂,设计并合成了一系列5-溴-,5-甲基-,和5-未取代的3-硝基-1,2,4-三唑-1-乙酰胺类化合物,用HeLaS3细胞进行了体外试验。结果表明5-溴取代衍生物的增敏作用强于相应的5-甲基-或5-未取代的硝基三唑衍生物,但是它们的毒性亦增大。修饰1位乙酰胺侧链也可以改变化合物的增敏作用和亲脂性。在所测定的化合物中TA-101[2-(3-硝基-1-三唑基)乙酰胺]由于有高的增敏作用和低亲脂性,可能是一个有希望的放射增敏剂。 相似文献
55.
Ventolini G Neiger R Mathews L Adragna N Belcastro M 《American journal of perinatology》2008,25(2):79-83
We studied the effect of antenatal corticosteroids on the incidence of respiratory disorders in singleton neonates born between 34 and 36 weeks of gestation. Retrospective analysis was conducted of the incidence of respiratory distress syndrome (RDS) and other respiratory disorders (need for mechanical ventilation, continuous positive airway pressure, and prolonged oxygen therapy) among singleton neonates delivered between 34 and 36 weeks of gestation who were exposed to antenatal corticosteroids, compared with neonates who were not exposed. Statistical analyses included two-tailed T tests, two-way analysis of variance for continuous data, and chi-square analysis for ratios. A probability of 0.05 was considered significant. Between January 1, 2000, and December 31, 2004, 1078 neonates were born between 34 and 36 weeks of gestation. Information regarding antenatal corticosteroids was available in 1044: 574 neonates (53.2%) were exposed to antenatal corticosteroids and 470 (43.6%) were not. One thousand and eighteen neonates were admitted to the neonatal intensive care unit. Respiratory disorders were diagnosed in 140 of those exposed to antenatal steroids (24.4%) and in 382 of the nonexposed (81.3%) ( P < 0.0001). Two hundred and ten neonates (20.6%) developed RDS: Of those, 43 were exposed to antenatal corticosteroids and 167 were not (incidence of RDS was 7.5% and 35.5%, respectively; P = 0.0001). The beneficial effects of corticosteroids were similar in both genders. It appears that the exposure of singleton pregnancies to antenatal corticosteroids between 24 and 34 weeks of gestation is associated with a significantly lower incidence of respiratory disorders among neonates born at 34 to 36 weeks of gestation. Further studies are needed to determine whether administering antenatal steroids to women experiencing preterm labor after 34 weeks of gestation would be associated with a similar beneficial effect. 相似文献
56.
Several studies have explored the disproportionate number of children of color involved in child protective services, raising concerns that racial bias in the system results in more women of color being referred to child protection. The authors conducted a case series to analyze whether a woman's race and ethnicity influenced referrals to child protective services in a domestic violence context. Data were obtained through interview records of 263 women (38% women of color) at a Minneapolis-based advocacy and therapy organization. The findings suggest that women who face multiple forms of oppressions may have greater risk of being involved with child protection services. 相似文献
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59.
Margaret Giorgio Loraine Townsend Yanga Zembe Mireille Cheyip Sally Guttmacher Farzana Kapadia Cathy Mathews 《Journal of immigrant and minority health / Center for Minority Public Health》2017,19(4):883-890
Female cross-border migrants experience elevated risks for HIV, and migrants in South Africa may face additional risks due to the country’s underlying HIV prevalence. These risks may be mitigated by the receipt of social support. A behavioral risk-factor survey was administered using respondent-driven sampling. Multivariable regression models assessed the relationships between social support and two HIV outcomes: HIV serostatus and perceived HIV status. Low social support was not significantly associated with HIV status (aOR?=?1.03, 95?% CI 0.43–2.46), but was significantly related to a perception of being HIV positive (aPR?=?1.36, 95?% CI 1.04–1.78). Age, marital status, and education level were significantly associated with HIV serostatus. Illegal border-crossing, length of time in South Africa, anal sex, and transactional sex were significantly associated with aperception of being HIV positive. Future research should investigate how HIV risks and the receipt of social support change throughout the migration process. 相似文献