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1.
Newborn mammals, compared to adults, are extremely resistant to the CNS effects of hyperbaric oxygenation (HBO) induced by excessive generation of reactive oxygen species. This tolerance to HBO may be related to either physiological responses or the chemical characteristics of the immature brain, including a low cerebral blood flow and energy metabolism and a low concentration of polyunsaturated fatty acids. In adult mammals the main protective mechanism against CNS oxygen toxicity, besides endogenous antioxidants, is a transient HBO-induced cerebral vasoconstriction. How cerebral vasculature reacts to HBO in the immature brain is not known. We present indirect evidence suggesting that HBO in newborn rats induces a persistent cerebral vasoconstriction concurrently with a severe and maintained reduction in ventilation. It is speculated that the outcome of these physiologic responses to hyperoxic exposures may be: (a) extension of tolerance to both CNS and pulmonary oxygen poisoning; (b) creation of a profound hypoxic-ischemic condition in vulnerable neural structures: and (c) impairement of the circulatory and ventilatory responses to hypoxic stimuli on return to air consequent development of a secondary hypoxic-ischemic condition. These hypothetical pre- and post-HBO events may set the stage for the development of some delayed neurological disorders, including the retinopathy of prematurity and the retardation of brain development in fetuses or prematurely-born infants subjected to oxygen therapy.  相似文献   
2.
目的研究β-cat在新生儿细支气管中的表达情况,探讨β-cat在新生儿支气管发育中的作用。方法采用免疫组化(SP)法,检测22例尸检新生儿β-cat、GSK-3β在细支气管上皮细胞的表达,以12例儿童为对照。结果β-cat在新生儿组有6例出现细胞膜表达降低、3例出现胞质表达、2例胞核表达;对照组中2例胞膜表达减少,1例胞质表达。β-cat的平均光密度值在新生儿组为0·112±0·024,对照组为0·128±0·037。两组比较P>0·05,无显著性差异;GSK-3β平均光密度值在对照组为0·147±0·037,新生儿组为0·115±0·028,两组比较P<0·05,有显著性差异。结论β-cat在新生儿细支气管的异位表达,提示Wnt信号与支气管的发育成熟有关。  相似文献   
3.
Isovaleric acidemia (IVA) is a rare autosomal recessive disorder caused by a deficiency of isovaleryl-CoA dehydrogenase encoded by IVD gene. In this case study we report the first Saudi IVA patients from a consanguineous family with a novel transversion (p.G362V) and briefly discuss likely phenotype–genotype correlation of the disease in the Saudi population. We explored the functional consequences of the mutation by using various bioinformatics prediction algorithms and discussed the likely mechanism of the disease caused by the mutation.  相似文献   
4.
Intramuscular fat (IMF) % contributes positively to the juiciness and flavour of lamb and is therefore a useful indicator of eating quality. A rapid, non-destructive method of IMF determination like computed tomography (CT) would enable pre-sorting of carcasses based on IMF% and potential eating quality. Given the loin muscle (longissimus lumborum) is easy to sample, a single measurement at this site would be useful, providing is correlates well to other muscles. To determine the ability of CT to predict IMF%, this study used 400 animals and examined 5 muscles from three sections of the carcass: from the fore-section the m. supraspinatus and m. infraspinatus, from the saddle-section the m. longissimus lumborum and from the hind-section the m. semimembranosus and m. semitendinosus. The average CT pixel density of muscle was negatively associated with IMF% and can be used to predict IMF% although precision in this study was poor. The ability of CT to predict IMF% was greatest in the m. longissimus lumborum (slope −0.07) and smallest in the m. infraspinatus (slope −0.02). The correlation coefficients of IMF% between the five muscles were variable, with the highest correlation coefficients evident between muscles of the fore section (0.67 between the m. supraspinatus and the m. infraspinatus) and the weakest correlations were between the muscle of the fore and hind section. The correlation between the m. longissimus lumborum to the other muscles was fairly consistent with values ranging between 0.34 and 0.40 (partial correlation coefficient). The correlation between the proportion of carcass fat and the IMF% of the five muscles varied and was greatest in the m. longissimus lumborum (0.41).  相似文献   
5.
目的:探讨新生儿宫内细菌感染采用降钙素原(PCT)、白细胞介素-6(IL-6)、及C反应蛋白(CRP)诊断的临床价值。方法:根据感染结局将2013年3月~2014年9月在我院分娩且有宫内感染高危因素的179例新生儿分为感染组(34例)和无感染组(145例),检测两组的PCT、IL-6及CRP水平,并比较各项指标对宫内细菌感染的诊断价值。结果:感染组脐带血PCT、IL-6、CRP水平均高于无感染组,差异有统计学意义(P0.05)。感染组各单个指标阳性率、两指标联合的阳性率高于无感染组,差异均有统计学意义(P0.05),感染组中PCT、IL-6阳性率高于CRP,PCT+IL-6的阳性率高于PCT+CRP、IL-6+CRP,差异均有统计学意义(P0.05)。PCT+IL-6的灵敏度、准确率高于单个指标及其他两个指标联合检测的结果,差异有统计学意义(P0.05),各项指标检测的特异性比较,差异无统计学意义(P0.05)。结论:新生儿宫内感染采用脐带血PCT检测具有灵敏度高,特异性好的特点,联合IL-6检测是临床诊断新生儿宫内感染的最有效的方式。  相似文献   
6.
摘要 目的:分析"双期三步法"筛查诊断流程在西安咸阳地区新生儿先天性心脏病筛查中的推广与应用价值。方法:选取2021年1月1日-2021年12月31日在医院产检的胎儿和出生的新生儿作为研究对象,收集胎儿期、新生儿期和婴儿期的先心筛查数据,将新生儿分为杂音组、经皮氧饱和度阳性组、双阳性组,评价"双期三步法"筛查方法的使用价值。结果:共对12318例新生儿进行了筛查,筛查阳性497例。确诊126例,实际发病率为10.23‰。在确诊的例先心病患儿中,位于前3位的疾病类型分别为房间隔缺损66例(52.38%),室间隔缺损41例(32.54%),动脉导管未闭11例(8.73%)。杂音组184例,单纯心脏杂音筛查检出率1.49%,灵敏度为82.5%,特异度为99.3%。经皮氧饱和度阳性组147例,单纯经皮氧饱和度阳性筛查检出率1.19%,灵敏度为58.7%,特异度为99.4%。双阳性组166例,两项指标联合筛查检出率1.35%,灵敏度为94.4%,特异度为99.6%。结论:"双期三步法"筛查诊断流程特别是心脏听诊和经皮氧饱和度联合筛查有利于早期发现新生儿CHD,值得推广应用。  相似文献   
7.
目的搞清新生大鼠HPA轴改变在应激低反应时期(stress hyporesponsive period、SHRP))的核受体-MR(盐皮质激素受体)和GR(糖皮质激素受体)在海马和视交叉上核(SCN)的表达变化。从而进一步了解新生大鼠发育时间对MR和GR的影响。方法本研究应用免疫荧光技术研究了生后4d(PD4)和生后12d(PD12)的新生大鼠海马和SCN的MR、GR的表达。同时采用RIA方法测定了血清中皮质类固醇的浓度水平。结果RIA结果显示在应激低反应期给予刺激,血清皮质类固醇水平没有明显改变。在海马,PD12较PD4,MR-和GR-i mmunoreactivity在CA1区表达增强;在齿状回没有明显变化;在海马门(hilus)减弱。而在海马的CA3区和SCN中,PD4 GR-ir强烈表达,在PD12却下降。同时也发现在hilus细胞出现GR和nestin(巢蛋白)阳性表达的共存,但是却没有发现MR和nestin的共存。结论新生大鼠阶段,发育时间对MR和GR的影响因区域不同影响不同。GR和nestin(巢蛋白)的共存为探讨在新生大鼠阶段GR对神经干细胞的分化有否影响提供了实验资料。本研究也为进一步研究新生大鼠应激低反应状态下海马及SCN与低活性的HPA轴的关系提供了形态学依据。  相似文献   
8.
The Apgar scoring system is an easy and reliable method for evaluating both human and animal neonates. However, its use is not widespread in veterinary medicine. The current study assessed a modified Apgar scoring system for routine evaluation of newborn puppies. Heart rate, respiratory effort, reflex irritability, motility, and mucus color have been evaluated in the score. Specifically, we used 5 min after birth Apgar score to assess newborn viability and short-term survival prognosis, as well as related characteristics, in 193 puppies from 42 litters, 65 born by spontaneous delivery, 66 by assisted delivery, and 62 by cesarean section. The percentage of puppies that were dead 2 h after birth was higher in the 4 to 6 Apgar score group versus that in the 7 to 10 score group (P < 0.01) and in the 0 to 3 score group versus that in the 7 to 10 score group (P < 0.0001). Delivery method did not affect survival. There was a marked reduction in the number of puppies searching for the mammary gland in the 0 to 3 and 4 to 6 Apgar score groups compared with that in the 7 to 10 score group (P < 0.0001); there was a difference between the 0 to 3 and the 4 to 6 score groups as well (P < 0.05). Suckling/swallowing reflexes were present in fewer puppies in the 0 to 3 and 4 to 6 score groups compared with that in the 7 to 10 group (P < 0.0001), with no significant differences between the 0 to 3 and the 4 to 6 score groups.  相似文献   
9.
目的:探讨在母婴ABO血型不合引起的新生儿溶血病(HDN)中的血型分布。方法:对临床表现怀疑为HDN的1939例新生儿进行血清学试验检测,包括新生儿红细胞直接抗人球蛋白试验,红细胞抗体释放试验和游离抗体试验,同时检测母亲ABO血型和RhD血型。结果:1939例婴儿母亲血型均为O型RhD阳性。A型血新生儿818例,其中直接抗人球蛋白试验阳性率17.2%(141/818),红细胞抗体释放试验阳性率89.2%(730/818)。B型血婴儿1121例,其中直接抗人球蛋白试验阳性率10.9%(121/1121),红细胞抗体释放试验阳性率78.6%(881/1121)。结论:ABO血型不合引起的HDN中,A型新生儿比B型新生儿患病几率更大。  相似文献   
10.
目的分析新生儿胆汁淤积症患儿肠道菌群特征及其与分娩方式、喂养方式的关系。方法选择2018年6月至2019年6月我院收治的40例新生儿胆汁淤积症患儿作为观察组,选择同期入院的120例健康新生儿作为对照组,比较两组对象肠道菌群分布情况。各组对象进一步按不同喂养方式分为母乳喂养组和混合喂养组,按不同分娩方式分为阴道分娩组和剖宫产组,分析各组新生儿肠道菌群与分娩方式、喂养方式的相关性。结果观察组新生儿粪便中双歧杆菌、乳杆菌数量及双歧杆菌/大肠埃希菌值[(7.53±0.57)lg copies/g、(8.12±0.71)lg copies/g、1.06±0.18]明显少于对照组[(9.58±0.64)lg copies/g、(8.64±0.75)lg copies/g、1.39±0.22],大肠埃希菌数量[(7.28±0.85)lg copies/g]明显多于对照组[(6.81±0.63)lg copies/g]。观察组中,阴道分娩与剖宫产分娩患儿粪便中双歧杆菌、乳杆菌、大肠埃希菌数量及双歧杆菌/大肠埃希菌值差异均有统计学意义(P0.05)。观察组中,母乳喂养与混合喂养新生儿粪便中双歧杆菌、乳杆菌、大肠埃希菌数量及双歧杆菌/大肠埃希菌值差异均有统计学意义(P0.05)。结论新生儿胆汁淤积症患儿肠道菌群存在异常,且受到分娩方式和喂养方式的影响。  相似文献   
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