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21.
刘淑娥 《河北医学》2007,13(12):1217-1219
目的:从胃肠激素水平探讨健脾中药儿食儿食健宝颗粒治疗小儿厌食症的作用机制。方法:用饮食不当法复制幼龄厌食症大鼠模型,通过观察肠内P物质(SP)、血管活性肠肽(VIP)、生长抑制素(SS)水平的变化,以及胃肠病理形态学改变,观察儿食健宝颗粒的作用。结果:儿食健宝颗粒可以改善厌食症大鼠SP、VIP、SS水平变化及胃肠粘膜病理形态。结论:儿食健宝颗粒可改善厌食症大鼠胃肠黏膜的病理形态学改变,并对SP、VIP、SS具有调节与平衡作用。  相似文献   
22.
目的探讨哮喘患儿血清中肺表面活性蛋白A、D(SP-A,SP-D)、白介素8(IL-8)、免疫球蛋白E(IgE)含量的变化及其分析研究。方法测定30例儿童哮喘急性发作期和缓解期的SP-A、SP-D、IL-8、IgE及同期健康儿童30例。结果急性发作期的SP-A、SP-D水平均显著低于对照组(P<0.01),IL-8、IgE水平均显著高于对照组(P<0.01);缓解期的SP-A、SP-D水平明显高于发作期(P<0.05),IL-8水平明显低于发作期(P<0.05),IgE水平与发作期相比差异无显著性(P>0.05)。结论儿童哮喘的发作虽然是多种病因引起,IL-8、IgE等在其中的病理生理、免疫病理改变有重要作用。证明SP-A、SP-D含量及功能改变与哮喘的发病、发展关系密切。  相似文献   
23.
The superplastic tensile test was carried out on SP700 (Ti-4.5Al-3V-2Mo-2Fe) titanium alloy sheet at 760 °C by the method of maximum m value, and the microstructure characteristics were investigated to understand the deformation mechanism. The results indicated that the examined alloy showed an extremely fine grain size of ~1.3 μm and an excellent superplasticity with fracture elongation of up to 3000%. The grain size and the volume fraction of the β phase increased as the strain increased, accompanied by the elements’ diffusion. The β-stabilizing elements (Mo, Fe, and V) were mainly dissolved within the β phase and diffused from α to β phase furthermore during deformation. The increase in strain leads to the accumulation of dislocations, which results in the increase in the proportion of low angle grain boundaries by 15%. As the deformation process, the crystal of α grains rotated, and the texture changed, accompanied by the accumulation of dislocations. The phase boundary (α/β) sliding accommodated by dislocation slip was the predominant mechanism for SP700 alloy during superplastic deformation.  相似文献   
24.
The development of the SARS‐CoV‐2 pandemic caused a common appearance of severe pulmonary complications, rarely seen as a result of the other infections. These are pneumothorax, pneumomediastinum, emphysematous bullae, cavitary lung lesions, or subcutaneous emphysema. Their formation is influenced by both—the natural course of the disease and the treatment strategy adopted.  相似文献   
25.
26.

Purpose

The association between myeloperoxidase (MPO) polymorphism and the risk of cervical cancer is inconclusive. We performed a meta-analysis to clarify if a correlation exists between MPO polymorphism and the risk for developing cervical cancer.

Methods

All case-control research studies that determined a relationship between MPO and cervical cancer reported up until March 1, 2018 in PubMed, Web of Science, VIP, WanFang, and the CNKI Database were accessed and included. The strength of association was evaluated with pooled odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs). We used sensitivity analysis to detect the stability of our results, conducted Q-test to evaluate heterogeneity and applied Begg’s funnel plot and Egger’s test to investigate any publication bias among selected studies.

Results

In this meta-analysis, we included 5 eligible studies in the final evaluation, which included 1125 patients with cervical cancer and 1150 cancer-free control patients. A potential association between the MPO ?463 G?>?A polymorphism and cervical cancer risk was observed (recessive model: OR?=?0.65, 95%, CI: 0.43–0.98, P?=?0.038; homozygous model: OR?=?0.65, 95%, CI: 0.43–0.99, P?=?0.045), which indicates that genotype AA reduces the risk of cervical cancer by 35% compared to GG/GA or GG genotypes in our results. A stratified analysis by ethnicity identified a significant correlation among Caucasian patients (recessive model: OR?=?0.57, 95%, CI: 0.34–0.95, P?=?0.029; homozygous model: OR?=?0.60, 95%, CI: 0.36–0.99, P?=?0.048) and a stratified analysis by source of control identified a significant correlation among population-based studies.

Conclusions

Our results suggest that the presence of polymorphism, ?463 G?>?A in patients might offer them protection against cervical cancer. By implementing randomized case-control or cohort studies with larger sample sizes, the clinical significance of our results can be further strengthened and verified.  相似文献   
27.
28.
Gestational hypercholesterolemia has been recognized as a risk factor of some pregnancy complications. We supposed that maternal hypercholesterolemia modified the lipid profile of the fetus. Thirty pregnant women with hypercholesterolemia and matched controls were recruited and cord blood was sampled. Lipidomic analysis was used to evaluate the lipid profile change between the two groups. The results showed that the content of diacylglycerophosphocholines (PC) was significantly high in cord blood from hypercholesterolemic pregnant women. PC (16:0/20:4) and PC (18:0/20:4) were selected as the most important lipid species in cord plasma and their contents were positively related to the total cholesterol and high-density lipoprotein cholesterol levels in cord blood. The contents of these two PCs were significantly higher in the hypercholesterolemic group than in the control group. These results suggested that gestational hypercholesterolemia might program the phospholipid metabolism in offspring.  相似文献   
29.
宛传丹  黄宇烽  汪萍 《解剖学杂志》2005,28(6):635-637,F0002
目的:以原核表达的人精子蛋白SP22制备其兔多克隆抗体,研究人精子蛋白SP22在人睾丸和精子中的分布与定位。方法:在E.Coli中诱导表达SP22基因,以纯化出的重组人精子蛋白htSP22为抗原制备兔抗人SP22多克隆抗体,运用免疫组织化学分析SP22在人睾丸和精子中的分布与定位。结果:表达出了分子量约22000的重组htSP22蛋白,制备获得了能特异性识别睾丸、精子中天然SP22蛋白的兔抗人SP22多克隆抗体。免疫组织及细胞化学证明SP22存在于曲细精管中各类生精细胞及精子头部表面。结论:制备的抗体具有特异性,SP22存在于睾丸曲细精管中各类生精细胞及精子头部表面。  相似文献   
30.
This study compares brain activation patterns evoked by smooth pursuit and by fixation suppression of the optokinetic reflex (OKR) using similar retinal stimulation. Functional magnetic resonance imaging (fMRI) was performed during smooth pursuit stimulation in which a moving target was presented on a stationary pattern of stripes, and during fixation suppression of OKR in which a stationary target was presented on a moving pattern of stripes. All subjects could effectively ignore the background pattern and were able to keep the target continuously on the fovea with few saccades, in both experiments. Smooth pursuit evoked activation in the frontal eye fields (FEF), the supplementary eye fields (SEF), the parietal eye fields (PEF), the motion-sensitive area (MT/V5), and in lobules and vermis VI of the cerebellum (oculomotor areas). Fixation suppression of OKR induced activation in the FEF, PEF, and MT/V5. The direct comparison analysis revealed more activation in the right lobule VI of the cerebellum and in the right lingual and calcarine gyri during smooth pursuit than during fixation suppression of OKR. Using similar retinal stimulation, our results show that smooth pursuit and fixation suppression of the OKR appear to activate largely overlapping pathways. The increased activity in the oculomotor areas of the cerebellum during smooth pursuit is probably due to the presence of an active eye movement component.  相似文献   
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