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21.
Good nutritional support is crucial for the immune system to fight against coronavirus disease 2019 (COVID-19). However, in the context of a pandemic with a highly transmissible coronavirus, implementation of nutrition practice may be difficult. A multicenter electronic survey involving 62 dieticians was conducted, in order to understand barriers associated with dieticians’ adherence to nutrition guidelines for hospitalized COVID-19 patients in Indonesia. 69% of dieticians felt under stress when performing nutrition care, and 90% took supplements to boost their own immunity against the coronavirus. The concerns related to clinical practice included a lack of clear guidelines (74%), a lack of access to medical records (55%), inadequate experience or knowledge (48%), and a lack of self-efficacy/confidence (29%) in performing nutritional care. Half (52%) of the dieticians had performed nutrition education/counseling, 47% had monitored a patient’s body weight, and 76% had monitored a patient’s dietary intake. An adjusted linear regression showed that guideline adherence independently predicted the dieticians’ nutrition care behaviors of nutrition counselling (ß: 0.24 (0.002, 0.08); p = 0.04), and monitoring of body weight (ß: 0.43 (0.04, 0.11); p = 0.001) and dietary intake (ß: 0.47(0.03, 0.10); p = 0.001) of COVID-19 patients. Overall, adherence to COVID-19 nutrition guidelines is associated with better nutritional management behaviors in hospitalized COVID-19 patients.  相似文献   
22.
目的:研究玻璃体视网膜手术的主要致病。方法:对449例玻璃体视网膜手术做回顾性分析,男243例,女206例,术前视力光感-0.2;平均病史11.6月,手术采用三切口闭合式玻璃体切割术,结果:449例诊断明确,与术前诊断符合率为80.6%,病因中视网膜血管性疾病114例,占25.39%,眼外伤85例,占18.93%,糖尿病视网膜病变82例,占18.26%,黄斑部病变41例,占9.13%,孔源性视网膜脱离39例,占8.69%,眼内炎25例,占5.57%,结论:玻璃体视网膜手术正走向成熟,其适应证逐渐扩展,已成为治疗眼后段疾病的重要手段。  相似文献   
23.
闭合性腹部损伤是腹部外科的常见急症 ,并发症发生率及死亡率较高 ,因此早期诊断和及时处理至关重要。我院自1991年 1月至 2 0 0 1年 1月共收治闭合性腹部损伤 42 8例 ,就其早期诊断和治疗分析如下。1 临床资料1.1 一般资料 本组 42 8例 ,男 346例 ,女 82例 ,年龄 6~ 72岁 ,其中 2 0~ 45岁 2 6 5例 ,占 6 2 %。致伤原因 :车祸伤 184例 ,坠落伤 81例 ,挤压伤 6 4例 ,打击伤 6 8例 ,跌伤 31例。损伤类型 :单纯腹部损伤占 72 % (30 8/ 42 8) ,其中单一脏器损伤占 85 % (2 6 1/ 30 8) ,两个以上脏器损伤占 15 % (47/ 30 8) ;两个或以上部位…  相似文献   
24.
Pig organ xenotransplantation offers a solution to the shortage of deceased human organs for transplantation. The pathobiological response to a pig xenograft is complex, involving antibody, complement, coagulation, inflammatory, and cellular responses. To overcome these barriers, genetic manipulation of the organ‐source pigs has largely been directed to two major aims—(a) deletion of expression of the known carbohydrate xenoantigens against which humans have natural (preformed) antibodies, and (b) transgenic expression of human protective proteins, for example, complement‐ and coagulation‐regulatory proteins. Conventional (FDA‐approved) immunosuppressive therapy is unsuccessful in preventing an adaptive immune response to pig cells, but blockade of the CD40:CD154 costimulation pathway is successful. Survival of genetically engineered pig kidneys in immunosuppressed nonhuman primates can now be measured in months. Non‐immunological aspects, for example, pig renal function, a hypovolemia syndrome, and rapid growth of the pig kidney after transplantation, are briefly discussed. We suggest that patients on the wait‐list for a deceased human kidney graft who are unlikely to receive one due to long waiting times are those for whom kidney xenotransplantation might first be considered. The potential risk of infection, public attitudes to xenotransplantation, and ethical, regulatory, and financial aspects are briefly addressed.  相似文献   
25.
目的通过系统评价和Meta分析探讨阿帕替尼与替吉奥对比治疗结肠癌的有效性和安全性。方法以"阿帕替尼""替吉奥""结肠癌""等为中文关键词,以"Apatinib""Tegafur""Colon cancer"等为英文关键词,检索PubMed,Cochrane Library,Embase,Web of Science,中国知网、中国生物医学文献服务系统、维普数据库、万方数据知识服务平台,时间限制在从建库到2020年12月。评价阿帕替尼和替吉奥对结肠癌的总体疗效,结肠癌进展和无进展生存期的差异。研究采用RevMan 5.3软件进行Meta分析。结果Meta分析结果显示,阿帕替尼与替吉奥对结肠癌的疗效相比,部分缓解+稳定的差异没有统计学意义(RR=1.10,95%CI,0.71~1.71,P=0.640),在结肠癌进展方面的差异没有统计学意义(RR=0.51,95%CI:0.28~1.32,P=0.205),在无进展生存期方面阿帕替尼组大于替吉奥组,差异具有统计学意义(SMD=0.90,95%CI;0.42~1.37,P<0.0001)。结论相较于替吉奥,阿帕替尼用于治疗结肠癌患者能明显延长无进展生存期,总体生存效益有所提高。  相似文献   
26.
BackgroundROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.MethodWe conducted a phase IV clinical trial in healthy infants aged 6–8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.ResultsA total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.ConclusionsThe complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam.  相似文献   
27.
Why do A.T base pairs inhibit Z-DNA formation?   总被引:1,自引:0,他引:1       下载免费PDF全文
We have carried out free energy perturbation calculations on DNA double-stranded hexanucleotides. The sequence d(CGCGCG)2 has been "mutated" into d(CGTGCG).d(CGCACG) with the oligonucleotide in the A, B, and Z structural forms, both in vacuo and in aqueous solution. In addition, model free energy calculations have been carried out in which the electrostatic charges of the H-bonding groups of the bases in the major and minor grooves of the DNA are reduced to zero as a way of assessing the relative solvation effects of these groups in the different structural forms of DNA. Finally, energy component analyses have been carried out to assess the relative roles of different intranucleotide interactions on the B----Z equilibrium as a function of base sequence. In vacuo, the free energy for changing a G.C to an A.T base pair is largest in the Z conformation; in the A and B conformations, the free energy cost is approximately 2 kcal/mol lower (1 cal = 4.184 J). The results are similar when the simulations are run in explicit solvent: the change costs 3 kcal/mol more in the Z conformation than in the B form. These results are consistent with experimental data, where it is clear that A.T sequences are significantly more "Z-phobic" than G.C sequences. The calculations indicate that both intranucleotide and solvation interactions contribute to this Z-phobicity.  相似文献   
28.
29.
采用反相高效液相色谱蒸发激光散射检测器测定三七中人参皂苷Rg1的含量。色谱柱为CLC-ODS(6.0mm×150mm),流动相为乙腈-水(3070),蒸发激光散射检测器。定量方法简单,准确。回收率为100.50%,RSD为1.82%。并用紫外分光光度法测定了三七中总皂苷的含量,结果和HPLC法基本一致,说明该方法定量准确,回收率为101.50%,RSD为1.44%。结论认为两方法均可以控制三七的质量。  相似文献   
30.
Residues energetically linked to the allosteric transition of thrombin from its anticoagulant slow form to the procoagulant fast form have been identified by site-directed mutagenesis. The energetics of recognition by the two forms of the enzyme were probed by using a synthetic chromogenic substrate, fibrinogen, and hirudin. The thrombin residues E39, W60d, E192, D221, and D222 are linked to the slow-->fast transition and are part of an "allosteric core" through which events originating at the Na+ binding loop propagate to other regions of the enzyme. The thrombin residues Y76, W96, W148, and R173 lie at the periphery of the allosteric core, affect recognition of fibrinogen and hirudin to the same extent in both forms, and are not linked to the slow-->fast transition.  相似文献   
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