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991.
Aim: To test the hypothesis that implementing guidelines for the standardized care of the extremely premature infant (<27 weeks) in the first week of life would improve patient outcomes in an all referral NICU. Methods: Data were collected on all infants <27 weeks gestational age and <7 days of age on admission cared for using these small baby guidelines (SBG), as well as on all age‐matched infants admitted the year prior (comparison). Results: Thirty‐seven patients were cared for utilizing the SBG and 40 patients were in the comparison group. There were no differences between the groups in gestational age, birthweight or age on admission. There was no difference in survival to discharge (73% SBG, 70% comparison). The mean length of stay for survivors was 112 ± 38 days SBG and 145 ± 76 days (p < 0.05) comparison group. Survival without BPD was greater in the SBG group (24%) than in the comparison group (9%; p < 0.05), and survival without severe IVH was greater in the SBG group (65%) than in the comparison group (38%; p < 0.01). Conclusions: These data demonstrate that applying a unified approach to the care of the extremely premature infant in the first week of life resulted in a decrease in the length of hospitalization and improved patient outcomes.  相似文献   
992.
Children with attention-deficit hyperactivity disorder (ADHD) are impulsive, and that impulsiveness can be measured using a countermanding task. Although the overt behaviors of ADHD attenuate with age, it is not clear how well impulsiveness is controlled in adults with ADHD. We tested ADHD adults with an oculomotor countermanding task. The task included two conditions: on 75% of the trials, participants viewed a central fixation marker and then looked to an eccentric target that appeared simultaneous with the disappearance of the fixation marker; on 25% of the trials, a signal was presented at variable delays after target appearance. The signal instructed subjects to stop, or countermand, an eye movement to the target. A correct movement in this case would be to hold gaze at the central fixation location. We expected ADHD participants to be impulsive in their countermanding performance. Additionally, we expected that a visual stop signal at the central fixation location would assist oculomotor countermanding because the signal is presented in the "stop" location, at fixation. To test whether a central stop signal positively biased countermanding, we used a three types of stop signal to instruct the stop: a central visual marker, a peripheral visual signal, and a non-localized sound. All subjects performed best with the central visual stop signal. Subjects with ADHD were less able to countermand eye movements and were influenced more negatively by the non-central signals. Oculomotor countermanding may be useful for quantifying impulsive dysfunction in adults with ADHD especially if a non-central stop signal is applied.  相似文献   
993.

Objectives

The aim was to determine the incidence, causes and the maternal mortality associated with postpartum haemorrhage in a tertiary centre in Nigeria.

Methods

Case records of all patients that had postpartum haemorrhage after vaginal delivery at Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife unit over a 5-year period (January 1st, 2002 to December 31st, 2006) were reviewed and analysed. Post-partum blood loss was calculated by estimating blood loses in graduated containers and in bed lines and gauze packs.

Results

112 women had postpartum haemorrhage during the period under review. 76(67.86%) had primary postpartum haemorrhage and 36(32.14%) had secondary postpartum haemorrhage. The commonest cause of post partum haemorrhage was retained products of conception due mismanagement of the third stage of labour, this occurred in 88 women (78.57%) of cases. Other causes were uterine atony 12(10.71%), genital tract laceration 9(8.04%), disseminated intravascular coagulopathy 1(0.8%) puerperal sepsis 1(0.8%) and broken down episiotomy, 1(0.8%). The maternal mortality during the period was 90 out of which 6 were due to postpartum haemorrhage. Conclusion: Retained products of conception resulting from mismanagement of the third stage of labour is the most common cause of post partum haemorrhage in our centre.  相似文献   
994.
目的探讨去铁胺(DFO)对新生大鼠缺氧缺血性脑损伤(HIBD)后海马DG区5-溴-2-脱氧尿嘧啶核苷(BrdU)和巢蛋白(nestin)表达的影响。方法选用7日龄新生Wistar大鼠制作新生大鼠HIBD模型,随机分为HIBD对照组和DFO干预组,并设置假手术组。DFO干预组于脑缺氧缺血后0、24、48 h腹腔注射DFO,每次0.2 mg/g。术后4 d检测脑组织病理改变,采用间接免疫荧光组织化学技术检测海马DG区nestin、BrdU表达;于大鼠32日龄时用Morris水迷宫检测大鼠的空间学习、记忆能力。结果术后4 d,假手术组、HIBD对照组和DFO干预组大鼠的Brdu阳性细胞中位数和四分位数间距分别为(11.00,18.25)、(32.50,25.50)和(44.00,35.25),三组比较差异有统计学意义(P<0.01);nestin阳性细胞荧光强度分别为0.1279±0.0037、0.1330±0.0032、0.1365±0.0018,三组比较差异有统计学意义(P<0.01)。Morris水迷宫试验:三组大鼠的逃避潜伏期差异无统计学意义(P>0.05);假手术组、HIBD对照组、DFO治疗组大鼠的穿环指数分别为6.38±2.39、2.88±1.25和5.25±2.76,三组比较差异有统计学意义(P<0.05),两两比较,假手术组与HIBD对照组、DFO治疗组与HIBD对照组之间的差异有统计学意义(P<0.05),DFO治疗组与假手术组的差异无统计学意义(P>0.05)。结论DFO早期干预可增加新生鼠HIBD后海马DG区nestin、BrdU的表达,改善HIBD新生大鼠的空间学习记忆能力。  相似文献   
995.

Background and purpose:

Bradykinin (BK) and B2 receptors have been implicated in the pathophysiology of osteoarthritis (OA), and synovitis is one of its hallmarks. Here, the selective B2 receptor antagonists MEN16132 and icatibant have been pharmacologically characterized in human synovial cells.

Experimental approach:

Radioligand and functional studies (inositol phosphate (IP) accumulation, interleukin (IL)-6 and IL-8 release) were performed in cultured synoviocytes.

Key results:

[3H]-BK saturation studies indicated receptor density (Bmax) and Kd values of 121 550 sites per cell and 1.14 nM respectively. In synoviocytes, MEN16132 (pKi 8.9) was threefold more potent than icatibant (pKi 8.4). Both antagonists showed competitive antagonism in the BK-induced IP assay (control EC50 0.45 nM), with pKB values of 9.9 (MEN16132) and 8.1 (icatibant). 24h incubation with BK induced IL-6 (EC50 216 nM) and IL-8 (EC50 53 nM) release. Both MEN16132 (IL-6: pIC50 8.1; IL-8: pIC50 8.4) and icatibant (IL-6: pIC50 6.6; IL-8: pIC50 6.7) completely prevented this BK-induced release. Indomethacin did not affect the basal or the IL-6/IL-8 release induced by BK, whereas nordihydroguaiaretic acid decreased the basal release, although BK still increased IL-6 and IL-8 production. BK-induced IL-8 release was attenuated by inhibitors of phospholipase C (U73122), p38 (SB203580), JNK (SP600125), ERK 1/2 (PD98059) MAPKs, phosphoinositide 3-kinase (LY294002), NF-κb (BAY-117085) and by the glucocorticoid dexamethasone.

Conclusions and implications:

Bradykinin via B2 receptors can participate in inflammatory events in synovitis. MEN16132 is a highly potent B2 receptor antagonist capable of blocking pro-inflammatory responses to BK evoked in human synoviocytes.  相似文献   
996.
Idiopathic developmental disability (DD) has been found to put significant psychological distress on families of children with DD. The cause of the disability, however, is unknown for up to one-half of the affected children. Chromosomal abnormalities identified by cytogenetic analysis are the most frequently recognized cause of DD, although they account for less than 10% of cases. Array genomic hybridization (AGH) is a new diagnostic tool that provides a much higher detection rate for chromosomal imbalance than conventional cytogenetic analysis. This increase in diagnostic capability comes at greater monetary costs, which provides an impetus for understanding how individuals value genetic testing for DD. This study estimated the willingness to pay (WTP) for diagnostic testing to find a genetic cause of DD from families of children with DD. A discrete choice experiment was used to obtain WTP values. When it was assumed that AGH resulted in twice as many diagnoses and a 1-week reduction in waiting time compared with conventional cytogenetic analysis, this study found that families were willing to pay up to CDN$1118 (95% confidence interval, $498–1788) for the expected benefit. These results support the conclusion that the introduction of AGH into the Canadian health care system may increase the perceived welfare of society, but future studies should examine the cost-benefit of AGH vs cytogenetic testing.  相似文献   
997.
Mutations in ROR2 , encoding a receptor tyrosine kinase, can cause autosomal recessive Robinow syndrome (RRS), a severe skeletal dysplasia with limb shortening, brachydactyly, and a dysmorphic facial appearance. Other mutations in ROR2 result in the autosomal dominant disease, brachydactyly type B (BDB1). No functional mechanisms have been delineated to effectively explain the association between mutations and different modes of inheritance causing different phenotypes. BDB1-causing mutations in ROR2 result from heterozygous premature termination codons (PTCs) in downstream exons and the conveyed phenotype segregates as an autosomal dominant trait, whereas heterozygous missense mutations and PTCs in upstream exons result in carrier status for RRS. Given that the distribution of PTC mutations revealed a correlation between the phenotype and the mode of inheritance conveyed, we investigated the potential role for the nonsense-mediated decay (NMD) pathway in the abrogation of possible aberrant effects of selected mutant alleles. Our experiments show that triggering or escaping NMD may cause different phenotypes with a distinct mode of inheritance. We generalize these findings to other disease-associated genes by examining PTC mutation distribution correlation with conveyed phenotype and inheritance patterns. Indeed, NMD may explain distinct phenotypes and different inheritance patterns conveyed by allelic truncating mutations enabling better genotype–phenotype correlations in several other disorders.  相似文献   
998.
目的构建Rho蛋白鸟苷解离抑制因子(LyGDI)真核表达载体并建立稳定转染A549细胞株。方法PCR扩增LyGDI基因片段,构建pEGFP-C1-LyGDI真核表达载体,经酶切、PCR、测序验证其正确性。脂质体法转染真核细胞A549,G418筛选建立稳定转染的细胞株,RT-PCR、免疫印迹检测稳定转染的细胞株。结果构建了真核表达载体并建立了稳定转染的A549细胞株,成功表达LyGDI蛋白。结论LyGDI真核表达载体成功构建及稳定转染A549细胞株的建立,为研究LyGDI过度表达对肿瘤侵袭性和转移的影响奠定了实验基础。  相似文献   
999.

Background and purpose:

The histamine H4 receptor is widely expressed in cells of immune origin and has been shown to play a role in a variety of inflammatory processes mediated by histamine. In this report, we describe the in vitro and in vivo anti-inflammatory properties of a potent histamine H4 receptor antagonist, A-940894 (4-piperazin-1-yl-6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-d]pyrimidin-2-ylamine).

Experimental approach:

We have analysed the pharmacological profile of A-940894 at mouse native, rat recombinant and human recombinant and native, histamine H4 receptors by radioligand binding, calcium mobilization, mast cell shape change, eosinophil chemotaxis assays and in the mouse model of zymosan-induced peritonitis.

Key results:

A-940894 potently binds to both human and rat histamine H4 receptors and exhibits considerably lower affinity for the human histamine H1, H2 or H3 receptors. It potently blocked histamine-evoked calcium mobilization in the fluorometric imaging plate reader assays and inhibited histamine-induced shape change of mouse bone marrow-derived mast cells and chemotaxis of human eosinophils in vitro. In a mouse mast cell-dependent model of zymosan-induced peritonitis, A-940894 significantly blocked neutrophil influx and reduced intraperitoneal prostaglandin D2 levels. Finally, A-940894 has good pharmacokinetic properties, including half-life and oral bioavailability in rats and mice.

Conclusions and Implications:

These data suggest that A-940894 is a potent and selective histamine H4 receptor antagonist with pharmacokinetic properties suitable for long-term in vivo testing and could serve as a useful tool for the further characterization of histamine H4 receptor pharmacology.  相似文献   
1000.

Background and purpose:

Protein kinase (PK) A and the ε isoform of PKC (PKCε) are involved in the development of hypernociception (increased sensitivity to noxious or innocuous stimuli) in several animal models of acute and persistent inflammatory pain. The present study evaluated the contribution of PKA and PKCε to the development of prostaglandin E2 (PGE2)-induced mechanical hypernociception.

Experimental approach:

Prostaglandin E2-induced mechanical hypernociception was assessed by constant pressure rat paw test. The activation of PKA or PKCε was evaluated by radioactive enzymic assay in the dorsal root ganglia (DRG) of sensory neurons from the hind paws.

Key results:

Hypernociception induced by PGE2 (100 ng) by intraplantar (i.pl.) injection, was reduced by i.pl. treatment with inhibitors of PKA [A-kinase-anchoring protein St-Ht31 inhibitor peptide (AKAPI)], PKCε (PKCεI) or adenylyl cyclase. PKA activity was essential in the early phase of the induction of hypernociception, whereas PKC activity was involved in the maintenance of the later phase of hypernociception. In the DRG (L4-L5), activity of PKA increased at 30 min after injection of PGE2 but PKC activity increased only after 180 min. Moreover, i.pl. injection of the catalytic subunit of PKA induced hypernociception which was markedly reduced by pretreatment with an inhibitor of PKCε, while the hypernociception induced by paw injection of PKCε agonist was not affected by an inhibitor of PKA (AKAPI).

Conclusions and implications:

Taken together, these findings are consistent with the suggestion that PKA activates PKCε, which is a novel mechanism of interaction between these kinases during the development of PGE2-induced mechanical hypernociception.  相似文献   
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