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1.
ObjectivesTo explore the relationships among potentially modifiable factors related to childbirth and effective breastfeeding initiation at approximately 36 hours after birth and duration and exclusivity at hospital discharge, 2 weeks, 2 months, and 6 months after birth in primiparous women and to explore whether modifiable and nonmodifiable secondary factors and covariates influenced the relationships among factors related to childbirth and these breastfeeding outcomes.DesignA prospective, longitudinal, cohort study.SettingThe postpartum units of two general hospitals in eastern Canada.ParticipantsNinety-seven mother–infant dyads.MethodsWe recorded demographic, childbirth, obstetric history, and breastfeeding data through chart review. A breastfeeding observation was completed at approximately 36 hours after birth by unit nurses. Participants maintained breastfeeding logs in hospital and for 6 months after birth and completed three self-report questionnaires before discharge. We analyzed outcomes using backward stepwise linear and logistic regression.ResultsOne childbirth factor, labor induced with oxytocin, was negatively associated with effective initiation of breastfeeding, and none was related to breastfeeding duration and exclusivity at any time point. Maternal weight; professional support; and newborn’s gestational age at birth, 5-minute Apgar score, weight loss, LATCH score, and active feeds (newborn actively suckled at the breast) were significantly associated with breastfeeding outcomes.ConclusionInduction of labor with oxytocin should be used judiciously; when used, nurses must be hypervigilant to assess the mother–infant dyad for breastfeeding issues and to intervene to prevent or remediate them.  相似文献   
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目的:采用高效液相色谱-三重四级杆质谱(HPLC-MS/MS)测定清血八味片中的化学成分。方法:在负离子条件下采用Halo C_(18)色谱柱(2.1 mm×100 mm,2.7μm),以0.1%甲酸-10 mmol/L甲酸铵水和乙腈为流动相进行梯度洗脱,质谱采用Scan模式和MRM模式,检测清血八味片中的化学成分。结果:共鉴定出紫草中成分7种、土木香中成分3种、人工牛黄中成分4种、栀子中成分7种、瞿麦中成分7种、甘草中成分12种。结论:该方法快速可靠,操作简便,可用于清血八味片的质量控制研究,为临床药物使用提供一定的依据。  相似文献   
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ObjectiveImprovement in the quality of life is reflected in the narrowing of the gap between health-adjusted life expectancy (HALE) and life expectancy (LE). The effect of megacity expansion on narrowing the gap is rarely reported. This study aimed to disclose this potential relationship.MethodsAnnual life tables were constructed from identified death records and population counts from multiple administrative sources in Guangzhou, China, from 2010 to 2020. Joinpoint regression was used to evaluate the temporal trend. Generalized principal component analysis and multilevel models were applied to examine the county-level association between the gap and social determinants.ResultsAlthough LE and HALE in megacities are increasing steadily, their gap is widening. Socio-economic and health services are guaranteed to narrow this gap. Increasing personal wealth, a growing number of newborns and healthy immigrants, high urbanization, and healthy aging have helped in narrowing this gap.ConclusionIn megacities, parallel LE and HALE growth should be highly considered to narrow their gap. Multiple social determinants need to be integrated as a whole to formulate public health plans.  相似文献   
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Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla.   总被引:2,自引:0,他引:2  
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner.  相似文献   
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分瓶法测定果蝇吸入麻醉药半数麻醉有效浓度   总被引:2,自引:1,他引:1  
目的 建立测定果蝇吸入麻醉药半数麻醉有效浓度 (ED50 )的方法学。方法 在 11个 32 5ml的三角烧瓶中各放入 30只雄性果蝇 ,分别加入不同容量的异氟醚标准气 ,使 11个烧瓶中异氟醚浓度分布在零效应浓度与百分之百效应浓度之间。以果蝇失去附壁及运动能力为标准计算各瓶中被麻醉果蝇数 ,用正规法计算出ED50 。结果  11次实验在 2 5及 5 0min时的量 -效关系曲线均呈S形 ,用各自的对数浓度与概率单位作图都呈直线相关 ,相关系数分别为 0 .972± 0 .0 14和 0 .971± 0 .0 2 5 ,ED50 值分别为 (0 .5 1± 0 .0 6 8) %和 (0 .4 7± 0 .0 85 ) % ,变异系数分别为 13.3%和 18.0 %。结论 本法稳定性较好 ,实用可行  相似文献   
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Amyloid P (AP) component is present in all types of systemic amyloid deposits. Recently, it has been shown to be also present in cerebral amyloid lesions of Alzheimer's disease (AD). In this study, we used immunocytochemical methods to extend these findings at the electron microscope level and characterize the spectrum of AP immunoreactivity in neurofibrillary pathology (NFP) of AD and other neurodegenerative disorders including Down's syndrome (DS), Creutzfeldt-Jakob, Parkinson's, Pick's and diffuse Lewy body diseases and progressive supranuclear palsy. In AD and DS, AP immunoreaction product was evident in all the classical amyloid lesions and NFP in a large sample of all cortical areas examined. The distribution and relative intensity of immunostaining was similar to that of thioflavin S staining in serial sections. In many cases, however, plaques and vessels stained by anti-AP serum were not apparent with thioflavin S. Serial sections immunostained with antiserum to amyloid A, C-reactive protein or to other proteins involved in systemic amyloidoses and the acute phase response showed no evidence of staining in any of the cerebral lesions. Electron microscopy confirmed that AP immunoreactivity was associated with the abnormal filaments characteristic of NFP as well as amyloid fibrils found in plaques and vessels showing congophilic amyloid angiopathy. Plaques of Creutzfeldt-Jakob disease, Pick bodies of Pick's disease, tangles and Lewy bodies in Parkinson's disease and a subpopulation of Lewy bodies in the diffuse Lewy body disease coexistent with AD were also stained. With the exception of vessels in two of the five cases, AP was not detected in age-matched controls. Our observations indicate AP to be a consistent feature of cerebral NFP and amyloid deposits.  相似文献   
10.
The use of automated blood processors in combination with bottom and top blood containers has been found to improve the standardization and quality of blood components. A study was performed to validate a new type of processor (Optipress® II) and compare its performance with a first generation processor (Optipress® I).
Primary separation on the Optipress II was investigated on 570 mL (± 10%) of anticoagulated blood in a nonpaired study. In addition, the quality of the products in routine production was compared between the results of the Optipress I and Optipress II. The whole blood units were kept overnight at room temperature (20 ± 2 °C). Separation was performed under conditions to obtain 55 mL buffy coats with a 50% haematocrit (ht). Platelet concentrate preparation was investigated in a paired study and compared to the routine manual method using PAS II additive solution. Parameters studied were volume, red cell, white cell and platelet counts, ht, haemoglobin (hb, total and free).
Primary separation was more efficient in the Optipress II because the platelet count was lower in the erythrocyte concentrates ( P  < 0.0001), platelets were lower in plasma ( P  < 0.0001) and platelet counts were higher in buffy coats ( P  < 0.0001). Buffy coat volume showed less variation (Optipress II VC = 4%, Optipress I VC = 7.4%). Secondary separation did not show differences between the Optipress II and manual method but was advantageous because of the automatic termination of the procedure.
Further improvement of standardization in blood component preparation is possible with an automated blood processor, leading to improvement of the quality of blood products for patient care.  相似文献   
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