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1.
目的:探讨母亲声音刺激联合非营养性吸吮对早产儿经口喂养的影响。方法:选取2018年1月至2018年12月间在本院新生儿科病房住院早产儿(200例)作为研究对象,随机分为对照组(70例)、研究组A(65例)、研究组B(65例)。对照组按照新生儿科常规管理,研究组A在常规管理基础上给予单纯母亲声音刺激,研究组B在常规管理、单纯母亲声音刺激基础上,给予非营养性吸允管理。比较各组的喂养进程、喂养表现、体质量增长情况、喂养不耐受评分。结果:研究组A、研究组B的完全经口喂养时的纠正胎龄(PMA)、过渡时间均明显短于对照组,且研究组B均明显短于研究组A,差异均有统计学意义(P0.05);研究组A、研究组B的开始经口喂养时喂养效率、完全经口喂养时喂养效率均明显高于对照组,且研究组B均明显高于研究组A,差异均有统计学意义(P0.05);研究组A、研究组B的完全经口喂养时体质量、出院时体质量均明显低于对照组,且研究组B均明显低于研究组A,差异均有统计学意义(P0.05)。研究组B与对照组间的喂养不耐受评分情况差异有统计学意义(P0.05)。结论:母亲声音刺激联合非营养性吸吮可促进早产儿经口喂养进程,改善经口喂养表现,减少喂养不耐受发生率,加快恢复至出生体质量的时间。  相似文献   

2.
Activation of a cytotoxic T cell requires specific binding of antigenic peptides to major histocompatibility complex (MHC) molecules. This paper reports a study of peptides binding to members of the HLA-A3 superfamily using a recently developed 2D-QSAR method, called the additive method. Four alleles with high phenotype frequency were included in the study: A*0301, A*1101, A*3101 and A*6801. The influence of each of the 20 amino acids at each position of the peptide on binding was studied. A refined A3 supertype motif was defined in the study.  相似文献   

3.
Point mutations of dehaloperoxidase-hemoglobin A (DHP A) that affect the surface charge have been prepared to study the interaction between DHP A with its substrate 2,4,6-trichlorophenol (TCP). Kinetic studies of these surface mutations showed a correlation, in which the more positively charged mutants have increased catalytic efficiency compared with wild type DHP A. As a result, the hypothesis of this study is that there is a global electrostatic interaction between DHP A and TCP. The electrostatic nature of substrate binding was further confirmed by the result that kinetic assays of DHP A were affected by ionic strength. Furthermore, isoelectric focusing (IEF) gel study showed that the pI-6.8 for DHP A, which indicates that DHP A has a slight negative charge pH 7, consistent with the kinetic observations.  相似文献   

4.
Ye Y  Wei J  Dai X  Gao Q 《Amino acids》2008,35(2):389-396
A molecular docking study was performed on several structurally diverse A(2A) AR antagonists, including xanthines, and non-xanthine type antagonists to investigate their binding modes with A(2A) adenosine receptor (AR), one of the four subtypes of AR, which is currently of great interest as a target for therapeutic intervention, in particular for Parkinson's disease. The high-affinity binding site was found to be a hydrophobic pocket with the involvement of hydrogen bonding interactions as well as pi-pi stacking interactions with the ligands. The detailed binding modes for both xanthine and non-xanthine type A(2A) antagonists were compared and the essential features were extracted and converted to database searchable queries for virtual screening study of novel A(2A) AR antagonists. Findings from this study are helpful for elucidating the binding pattern of A(2A) AR antagonists and for the design of novel active ligands.  相似文献   

5.
《Insulin》2008,3(4):219-231
Background: The Deep South Diabetes Program (DSDP) conducted a retrospective study to evaluate weight changes associated with intensive basal-bolus insulin therapy. Results of the effectiveness of the treatment algorithm that was used in this study were published in the April 2008 issue of Insulin.Objectives: The current study was designed to further evaluate the results of the DSDP study. The primary objective was to determine the quantitative relationship between weight gain and the patient's final glycosylated hemoglobin (A1C) level achieved. A secondary objective was to gain a qualitative understanding of the treatment parameters underlying the quantitative results.Methods: Further evaluation of the DSDP treatment algorithm in terms of weight management and A1C levels for achieving normoglycemia or near-normoglycemia was performed retrospectively using data collected in the original DSDP study. This evaluation included all patients who elected intensive basal-bolus insulin therapy and who sustained the treatment for up to 4 years. Glargine was the primary basal insulin, and aspart was the primary bolus insulin. The quantitative relationships among net weight change, net A1C change, and final A1C level achieved were evaluated. A qualitative evaluation of glycemic variability and behavioral variables was made from video recordings of patient visits during the original DSDP study and further observation of study participants after completion of the study.Results: Quantitative evaluation of change in weight as a function of A1C level achieved at the end of the study showed that for the group of patients who achieved normoglycemia, the mean change in weight was a reduction proportional to the corresponding mean reduction in A1C. For the groups of patients who did not achieve normoglycemia or near-normoglycemia, the mean change in weight was an increase proportional to the corresponding mean reduction in A1C.Conclusions: When normoglycemia was achieved and sustained using the DSDP's intensive insulin therapy, the weight gain typically seen with conventional insulin therapy did not occur. Weight gain or loss during intensive insulin therapy using the DSDP treatment algorithm was a function of A1C level achieved.  相似文献   

6.
本实验报道了以离体培养方式诱导日本冷杉(Abies firma Sieb.et Zucc.)与二色蜡蘑(Laccaria bicolor(Maire)Orton)的外生菌根合成的方法.日本冷杉能否与广谱性的外生菌根菌二色蜡蘑形成人工菌根?菌根结构的诱导是否只发生在植物体整体水平上?这些是本实验的关注点.研究结果显示:无菌幼苗接种10周后,在光学显微镜下可观察到典型的外生菌根的特征,即由高度分叉的外延菌丝体形成的厚实的菌套以及由内延菌丝体形成的哈蒂氏网.将来源于下胚轴的愈伤组织与二色蜡蘑的菌丝体进行共同培养,3周后,菌丝体开始接触愈伤组织的表面,并且侵入到愈伤组织的细胞间,形成拟哈蒂氏网结构.愈伤组织可以作为一种菌根学研究的有效的培养体系.这一方法可望为冷杉类植物菌根学的研究提供有效的实验工具.  相似文献   

7.
本实验报道了以离体培养方式诱导日本冷杉(AbiesfirmaSieb.etZucc.)与二色蜡蘑(Laccariabicolor(Maire)Orton)的外生菌根合成的方法。日本冷杉能否与广谱性的外生菌根菌二色蜡蘑形成人工菌根?菌根结构的诱导是否只发生在植物体整体水平上?这些是本实验的关注点。研究结果显示:无菌幼苗接种10周后,在光学显微镜下可观察到典型的外生菌根的特征,即由高度分叉的外延菌丝体形成的厚实的菌套以及由内延菌丝体形成的哈蒂氏网。将来源于下胚轴的愈伤组织与二色蜡蘑的菌丝体进行共同培养,3周后,菌丝体开始接触愈伤组织的表面,并且侵入到愈伤组织的细胞间,形成拟哈蒂氏网结构。愈伤组织可以作为一种菌根学研究的有效的培养体系。这一方法可望为冷杉类植物菌根学的研究提供有效的实验工具。  相似文献   

8.
The present study aimed to examine the working conditions of shift workers in a multinational enterprise in Thailand and to identify practical support measures for improvements. A multinational, glass-manufacturing factory employing 1,500 workers was selected as the research site. Three shift systems in three teams were adopted. A direct observation study and a fatigue feeling monitoring study were carried out to compare the differences between different shifts. A 10-day time-budget study was conducted for 30 shift workers to know their work and sleep patterns. The direct observation study identified safety and health risks during the night work periods. The risks included insufficient lighting, height gaps on the floor, excessive exposure to heat, inappropriate workstations, and sleepiness and fatigue feelings among shift workers. Working consecutive double shifts and overtime work was often seen. An advisory meeting was held based on the study findings to assist managers and workers in improving their working conditions. A follow-up visit six months later confirmed that the glass factory implemented several improvements to help night and shift workers. It was concluded that the direct observation methods associated with the time-budget study were helpful for identifying practical action points and strengthening workplace initiatives.  相似文献   

9.
Uridine 5′-diphospho-glucuronosyltransferase-1A9 (UGT1A9) expressed in the liver, shows good sequence identity with UGT1A10, expressed in the intestine. Both uridine 5′-diphospho-glucuronosyltransferase (UGT) isoforms show comprehensive overlapping substrate selectivity but there are differences in stereoselectivity, regiospecificity and rate of glucuronidation of the substrates. Multiple sequence alignment analyses of UGT1A9 and UGT1A10 showed that 13% of the residues in N-terminal domain (NTD) are non-identical between them. Herein, authors attempted homology modelling of UGT1A9 and UGT1A10 and validation using software tools and reported mutagenic studies. A molecular docking study of the known substrates is performed on UGT1A9 and UGT1A10 homology models. The non-identical N-terminal residues ranging from 111 to 117 in UGT1A9 and UGT1A10 were identified to play a central role in the substrate selectivity. However, substrate binding is performed by Ser111, Gly115 and Leu117 in UGT1A10 and Gly111, Asp115 and Phe117 in UGT1A9. This study reports new residues in NTD, showing interaction with uridine 5′-diphospho-glucuronic acid which binds with C-terminal domain. Further, molecular dynamics simulations were carried out to study the role of non-identical residues in substrate identification. The study demonstrates the folding of the UGT enzyme, particularly, helix-loop-helix transition and movement of Nα3-2 helix, in response to substrate and co-substrate binding.  相似文献   

10.
A 6 month study in rats fed a balanced diet containing 3,2 p. 100 tannic acid resulted in a marked decrease of the hepatic concentration of vitamin A. In an other study, rats were fed vitamin A deficient diets containing 0, 0,8, 1,6 and 3,2 p. 100 tannic acid. There was no effect of tannic acid on the hepatic concentrations of vitamin A determined on days 20, 40 and 60.  相似文献   

11.
Enzymatic, immunologic and hematologic dosages were performed in a group of blood donors. A significant part of this population showed anomalies in the enzymes, either isolated or associated and of variable importance. A systematic serological study of viral hepatitis A (VHA) and viral hepatitis B (VHB) was performed among these donors with biochemical anomalies. A more general biological study (immunology and hematology) completes this work.  相似文献   

12.
A. K. Kukushkin 《Biophysics》2013,58(1):133-136
Nowadays, spectroscopy methods are widely employed to study photosynthesis. For instance, fluorescence methods are often in use to study virtually all steps of the photosynthesis process. Theoretical models of phenomena under study are of importance for interpreting the experimental data. A decisive role of Lev A. Blumenfeld, the former Head of the Chair of Biophysics, Physical Faculty of the Moscow State University, in the study of photosynthesis is shown in this work.  相似文献   

13.
Objective: Adipocyte fatty acid‐binding protein (A‐FABP) is a plasma biomarker recently associated with the metabolic syndrome. The aim of these studies was to investigate changes of A‐FABP during profound weight loss induced by laparoscopic adjustable gastric banding (LAGB). Methods and Procedures: In study one, 29 severely obese female subjects were examined before and 1 year after surgical treatment. A subgroup of 10 patients was investigated in 3‐month intervals. Metabolic parameters were determined using standard methods, and A‐FABP was detected using a commercially available enzyme‐linked immunosorbent assay. Results: Mean weight loss after 1 year was 24.9 kg (P < 0.001), mainly due to a decrease in fat mass. Metabolic parameters improved substantially. However, serum A‐FABP remained stable. In study two, a subgroup of 10 patients was examined quarterly to determine the time course of A‐FABP changes. Quarterly measurements of serum A‐FABP were significantly higher than baseline levels with the highest A‐FABP value after the first 3 months, where patients had highest weight loss. Discussion: Our results in study one show that A‐FABP serum levels are positively associated with body weight and fat mass. However, 1 year after pronounced weight loss A‐FABP levels remained unchanged. In study two, time course analyses revealed maximum increase of serum A‐FABP in parallel to highest weight loss, which allows to suppose that A‐FABP is not only a biomarker of the metabolic syndrome in the steady state, but also a marker of weight changes in dynamic situations.  相似文献   

14.
Abstract:  Event MIR604 maize expresses a modified Cry3A protein (mCry3A), for control of corn rootworm. As part of the environmental safety assessment of MIR604 maize, risks to non-target organisms of mCry3A were assessed. The potential exposure of non-target organisms to mCry3A following cultivation of MIR604 maize was determined, and the hypothesis that such exposure is not harmful was tested. The hypothesis was tested rigorously by making worst-case or highly conservative assumptions about exposure, along with laboratory testing for hazards using species taxonomically related to the target pest and species expected to have high exposure to mCry3A, or both. Further rigour was introduced by study designs incorporating long exposures and measurements of sensitive endpoints. No adverse effects were observed in any study, and in most cases exposure to mCry3A in the study was higher than the worst-case expected exposure. In all cases, exposure in the study was higher than realistic, but still conservative, estimates of exposure. These results indicate minimal risk of MIR604 maize to non-target organisms.  相似文献   

15.
A recent study shows that the RASSF1A tumor suppressor functions as a regulator of the ordered proteolytic steps that organize mitosis. By controlling the stability of microtubules and the activity of the anaphase-promoting complex (APC), RASSF1A might provide a crucial link between mechanisms of tumor suppression and mitotic cell division. Furthermore, another recent study shows that protein kinase A, which is a key growth regulator, inhibits the APC during mitosis in yeast.  相似文献   

16.
The incidence of hepatitis A virus (HAV) infection has declined significantly worldwide, including in Japan. A nationwide seroepidemiological study on hepatitis A in Japan has taken place almost every 10 years since 1973, and the last study was performed in 2003. In the present study, we describe the latest seroepidemiological pattern of hepatitis A in Japan using 7867 serum specimens obtained from healthy individuals collected between 2013 and 2017, approximately 10 years after the last study. Among them, 223 were anti-HAV positive. About 68% of individuals aged 60 years and older had anti-HAV antibodies, whereas only 1.1% of those aged below 60 years old had immunity; thus, almost all individuals younger than 60 years of age were HAV susceptible. In comparison with previous investigations, the susceptible population has increased and aged. According to data from the National Epidemiological Surveillance of Infectious Diseases (NESID) program, between 1989 and 2016, the proportion of patients with hepatitis A aged 60 years and older continuously increased with each year. The NESID data also suggested that recently, typical large foodborne outbreaks of hepatitis A have become rare, and cases tend to be reported among at-risk groups; overseas travelers contributed to 25% of hepatitis A cases, and in 2018, the first nationwide hepatitis A outbreak that affected mostly men who have sex with men was reported. The purpose of this study was to determine the current status of HAV infection in Japan, based on both seroepidemiology and the national surveillance data from the NESID.  相似文献   

17.
Pathological folding and oligomer formation of the amyloid beta-protein (A beta) are widely perceived as central to Alzheimer's disease. Experimental approaches to study A beta self-assembly provide limited information because most relevant aggregates are quasi-stable and inhomogeneous. We apply a discrete molecular dynamics approach combined with a four-bead protein model to study oligomer formation of A beta. We address the differences between the two most common A beta alloforms, A beta 40 and A beta 42, which oligomerize differently in vitro. Our previous study showed that, despite simplifications, our discrete molecular dynamics approach accounts for the experimentally observed differences between A beta 40 and A beta 42 and yields structural predictions amenable to in vitro testing. Here we study how the presence of electrostatic interactions (EIs) between pairs of charged amino acids affects A beta 40 and A beta 42 oligomer formation. Our results indicate that EIs promote formation of larger oligomers in both A beta 40 and A beta 42. Both A beta 40 and A beta 42 display a peak at trimers/tetramers, but A beta 42 displays additional peaks at nonamers and tetradecamers. EIs thus shift the oligomer size distributions to larger oligomers. Nonetheless, the A beta 40 size distribution remains unimodal, whereas the A beta 42 distribution is trimodal, as observed experimentally. We show that structural differences between A beta 40 and A beta 42 that already appear in the monomer folding, are not affected by EIs. A beta 42 folded structure is characterized by a turn in the C-terminus that is not present in A beta 40. We show that the same C-terminal region is also responsible for the strongest intermolecular contacts in A beta 42 pentamers and larger oligomers. Our results suggest that this C-terminal region plays a key role in the formation of A beta 42 oligomers and the relative importance of this region increases in the presence of EIs. These results suggest that inhibitors targeting the C-terminal region of A beta 42 oligomers may be able to prevent oligomer formation or structurally modify the assemblies to reduce their toxicity.  相似文献   

18.
C Maire  M Bouchy  M Donner  J C André 《Biorheology》1992,29(5-6):507-519
A study of the labelling of isolated resealed erythrocyte membranes by TMA-DPH has been carried out. A quantitative study shows that saturation appears to take place when increasing the relative quantity of probe bulk concentration to membrane concentration; this is readily interpreted by a simple incorporation model with a limited number of sites in the membrane. A qualitative study shows that an increase in the labelling leads to an evolution of the probe fluorescence properties; the existence of different types of sites is involved in the interpretation but the system is too complex to allow it to be represented by a simple model. As a consequence of this study, care has to be taken in labelling biological material so as to avoid excessive probe incorporation.  相似文献   

19.
The need to identify anti-Flaviviridae agents has resulted in intensive biochemical study of recombinant nonstructural (NS) viral proteases; however, experimentation on viral protease-associated replication complexes in host cells is extremely challenging and therefore limited. It remains to be determined if membrane anchoring and/or association to replicase-membrane complexes of proteases, such as hepatitis C virus (HCV) NS3-4A, plays a regulatory role in the substrate selectivity of the protease. In this study, we examined trans-endoproteolytic cleavage activities of membrane-anchored and replicase-associated NS3-4A using an internally consistent set of membrane-anchored protein substrates mimicking all known HCV NS3-4A polyprotein cleavage sequences. Interestingly, we detected cleavage of substrates encoding for the NS4B/NS5A and NS5A/NS5B junctions, but not for the NS3/NS4A and NS4A/NS4B substrates. This stringent substrate recognition profile was also observed for the replicase-associated NS3-4A and is not genotype-specific. Our study also reveals that ER-anchoring of the substrate is critical for its cleavage by NS3-4A. Importantly, we demonstrate that in HCV-infected cells, the NS4B/NS5A substrate was cleaved efficiently. The unique ability of our membrane-anchored substrates to detect NS3-4A activity alone, in replication complexes, or within the course of infection, shows them to be powerful tools for drug discovery and for the study of HCV biology.  相似文献   

20.
阿胶冲剂与阿胶的化学成分对比分析研究   总被引:2,自引:0,他引:2  
阿胶在我国有着悠久的历史,是常用滋补中药,具有许多特殊的功效,国内外享有盛誉。据《本草纲目》及《本草纲目拾遗》等介绍,阿胶在明代以前系用(沙牛)牛,水牛,驴皮或猪、马、驼皮等杂皮熬制而成。自清代始一律采用黑驴皮熬制。以往服用阿胶必须将阿胶先用水浸泡后,然后加热溶解后才能服用.为了克服这一缺点,山东化工学院研制了一种用开水冲服的阿胶新制剂——阿胶冲剂.为了弄清阿胶经物理方法处理后的化学组成成份与原阿谱的化学组成成分的不同变化。我们对其所含微量元素、氨基酸进行了对比分析.另外,本文首次报道了阿胶及阿胶冲剂的红外光谱分析结果.  相似文献   

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