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The effect of cow's milk consumption on childhood asthma has been debated for several years. This study attempts to provide further insight into this association through the use of a longitudinal study design. Newborns from parents with atopic history were recruited from Germany, Austria, and England (n = 696). For five repeated ascertainments, information was collected on cow's milk exposure, incidence of doctor-diagnosed asthma, and confounders. Generalized estimation equations, incorporating different models (concurrent, delayed, combined, and reverse causation), were used to determine this association. No association between cow's milk consumption and childhood asthma was found for the concurrent effects model (OR = 0.81, 95% confidence interval [CI]: 0.55, 1.20). In the delayed effects model, the direction of the association varied with time of follow-up. Thus, we stratified by period, which resulted in a significant protective delayed effect at 36 months (OR = 0.18, 95% CI = 0.06, 0.49). However, reverse causation negated this finding since the presence of asthma in prior months led to a reduction in further exposure to cow's milk (OR = 0.40, 95% CI = 0.16, 0.99). Hence, cow's milk consumption does not protect against childhood asthma. The apparent protection of cow's milk against asthma may result from parents of asthmatic children avoiding cow's milk, rather than actual prophylaxis.  相似文献   
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实验水池是评价杀虫剂效应和安全生的重要场所,水池中无脊椎动物群落结构和种群动态是评价杀虫剂的基础资料和考核指标,本文报告1992年至1993年在美国佛罗里达中部地区对应用于杀虫剂评价的实验水池中昆虫与其它无脊椎动物群落结构及其优势种的种群动态研究结果,用羽化诱捕、勺舀、网拉及挖取底物法,从实验水池中共采到昆虫与其它无脊椎动物50余类,其中,羽化诱捕到的昆虫中摇蚊占93.9%,蜉蝣目昆虫占4.6%,  相似文献   
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Autosomal recessive nonsyndromic deafness is one of the most frequent forms of inherited hearing impairment. Over 30 autosomal recessive nonsyndromic hearing loss loci have been mapped, and 15 genes have been isolated. Of the over 30 reported autosomal recessive nonsyndromic hearing loss (NSHL) loci, the typical phenotype is prelingual non-progressive severe to profound hearing loss with the exception of DFNB8, which displays postlingual onset and DFNB13, which is progressive. In this report we describe a large inbred kindred from a remote area of Pakistan, comprising six generations and segregating autosomal recessive nonsyndromic prelingual deafness. DNA samples from 24 individuals were used for genome wide screen and fine mapping. Linkage analysis indicates that in this family the NSHL locus, (DFNB35) maps to a 17.54 cM region on chromosome 14 flanked by markers D14S57 and D14S59. Examination of haplotypes reveals a region that is homozygous for 11.75 cM spanning between markers D14S588 and D14S59. A maximum two-point LOD score of 5.3 and multipoint LOD score of 7.6 was obtained at marker D14S53. The interval for DFNB35 does not overlap with the regions for DFNA9, DFNA23 or DFNB5.  相似文献   
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Kinetochores play an essential role in chromosome segregation by forming dynamic connections with spindle microtubules. Here, we identify a set of 10 copurifying kinetochore proteins from Caenorhabditis elegans, seven of which were previously uncharacterized. Using in vivo assays to monitor chromosome segregation, kinetochore assembly, and the mechanical stability of chromosome-microtubule attachments, we show that this copurifying protein network plays a central role at the kinetochore-microtubule interface. In addition, our analysis suggests that the network is comprised of three groups of proteins that contribute in distinct ways to this interface: KNL proteins act after the assembly of centromeric chromatin to generate the core of the microtubule-binding interface, MIS proteins control the rate and extent of formation of this interface, and NDC proteins are necessary to sustain tension during interactions with spindle microtubules. We also purify a similar set of associated proteins from human cells that includes four novel proteins and has recognizable homologs from each functional class. Thus, this protein network is a conserved constituent of the outer kinetochore, and the functions defined by our analysis in C. elegans are likely to be widely relevant.  相似文献   
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This study reports the first evaluation of sperm hyaluronan binding assay (HBA) for predicting the fertility of Nili-Ravi buffalo bulls in relation to standard parameters of sperm quality. Cryopreserved semen doses of low (n = 6), medium (n = 3) and high fertility (n = 8) bulls based on their respective return rates were used. Significantly, more spermatozoa bound to hyaluronan from the most fertile bulls (57.15% ± 1.44) compared with medium (42.46% ± 1.08) and low fertility bulls (29.70% ± 0.78). A strongly positive correlation (r = .824, p < .01) was found between HBA and fertility that predicts a 67.9% variability (r2 = .679, p < .01) in fertility. HBA was also strongly positively correlated with sperm viability (r = .679, p < .01) followed by their live/dead ratio (r = .637, p < .01), uncapacitated spermatozoa (r = .631, p < .01), normal apical ridge (r = .459, p < .01), motility (r = .434, p < .01), mature spermatozoa with low residual histones (r = .364, p < .01), high plasma membrane integrity (r = .316, p < .01) and nonfragmented DNA levels (r = .236, p < .05). It was negatively correlated with spermatozoa having reacted acrosome (r = −.654, p < .01). A fertility model built using a combination of sperm HBA and either sperm livability or viability predicts, respectively, 86.1% (r2 = .861, p < .01) and 85.9% (r2 = .859, p < .01) variability in buffalo bull fertility. In conclusion, sperm HBA may prove to be a single robust predictor of Nili-Ravi buffalo bull fertility.  相似文献   
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PurposeRepetitive painful stimuli and early exposure to opioids places neonates at risk for neurocognitive delays. We aimed to understand opioid utilization for neonates with gastroschisis.MethodsWe performed a retrospective review of infants with gastroschisis at a tertiary children's hospital (2017–2019). Multivariate linear regression was performed to analyze variations in opioid use.ResultsAmong 30 patients with gastroschisis, 33% were managed by primary suture-less closure, 7% by primary sutured closure, 40% by spring silo, and 20% by handsewn silo. The proportion of pain medication used was: morphine (89%), acetaminophen (8%), and fentanyl (3%). Opioids were used for a median of 6.5 days (range 0–20) per patient. Median total opioid administered across all patients was 2.2 morphine milligram equivalents (MME)/kg (IQR 0.7–3.3). Following definitive closure, median opioid use was 0.2 MME/kg (IQR 0.1–0.8). With multivariate regression, 45% of the variation in MME use was associated with the type of surgery after adjusting for weight, gestational age, and gender, p = 0.02. After definitive fascial closure, there was no significant variations in opioid use.ConclusionThere is a significant variation in the utilization of opioid, primarily prior to fascial closure. Understanding pain needs and standardization may improve opioid stewardship in infants with gastroschisis. 197/200Level of EvidenceLevel III  相似文献   
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PurposePain control is challenging after minimally invasive repair of pectus excavatum (MIRPE). Cryoanalgesia, which temporarily ablates peripheral nerves, improves pain control and may accelerate post-operative recovery. We hypothesized that cryoanalgesia would be associated with shorter length of stay (LOS) in children undergoing MIRPE.MethodsA matched cohort study was conducted of children (<18 years) who underwent MIRPE 2016–2018, using the National Surgical Quality Improvement Program-Pediatric database. Each patient who received cryoanalgesia during MIRPE was matched to four controls (no cryoanalgesia). Univariate and multilevel regression analyses were performed.ResultsThirty-five patients who received cryoanalgesia during MIRPE were matched to 140 controls. Patients who received cryoanalgesia had a LOS reduction with similar secondary outcomes (operative time, rates of complication, reoperation, and readmission). On multilevel regression adjusted for matched groups, cryoanalgesia was associated with a 1.3-day reduction in LOS (95% CI ?1.8 to ?0.8, p < 0.001). On sensitivity analysis excluding patients with complications, cryoanalgesia remained associated with a LOS reduction.ConclusionsCryoanalgesia is a promising adjunct in the care of pediatric patients undergoing MIRPE. Utilization is associated with a shorter LOS without an increase in operative time or complications. Cryoanalgesia should be considered for inclusion in enhanced recovery strategies for patients undergoing MIRPE.  相似文献   
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