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排序方式: 共有7218条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2020,38(50):7916-7927
Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory illness in children of less than 5 years of age which usually results in hospitalization or even in death. Vaccine development is hampered in consequence of a failed vaccine trial with fatalities in the 1960s. Even though research has been more focused on the RSV fusion protein in its pre-fusion conformation, maternal vaccination with post-fusion protein (post F) was considered as a promising vaccine strategy for passive immunization of babies, because post F preserves very potent neutralizing epitopes. We extensively analyzed post F-binding B cell receptor (BCR) repertoires of three vaccinees who received a post F-subunit vaccine in the context of a first-in-human, Phase 1, randomized, observer-blind, placebo-controlled clinical trial (ClinicalTrials.gov Identifier: NCT02298179). In order to compare the vaccine-induced BCR repertoires with BCR repertoires induced by natural infection, we also analyzed pre F- and post F-binding BCRs isolated from a healthy blood donor with relatively high F-binding memory B cell (MBC) frequencies. Analysis of the vaccine-induced repertoires revealed that preferentially VH4-encoded BCRs were expanded in response to vaccination. Estimation of antigen-driven selection further demonstrated that expanded BCRs accumulated positively selected replacement mutations which substantiated the hypothesis that post F-vaccination induces diversification of VH4-encoded BCRs in germinal centers. Comparison of the vaccine-induced BCR repertoires with clonally related pre and post F-binding BCRs of the healthy blood donor suggested that the vaccine expanded pre/post F cross-reactive MBCs. Interestingly, several vaccine-induced BCRs shared stereotypic VDJ gene junctions with known neutralizing Abs. Once expressed for functional characterization, the selected monoclonal Abs demonstrated the predicted neutralization activities in plaque reduction neutralization assays indicating that the post F-vaccine induced expansion of neutralizing BCRs. 相似文献
2.
Mariano E. Menendez Suleiman Y. Sudah Patrick J. Denard 《Seminars in Arthroplasty》2022,32(3):644-649
BackgroundThe growing enthusiasm for the use of reverse shoulder arthroplasty (RSA) in the treatment of primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff is based on data derived from single-center studies with limited generalizability and follow-up. This study compared patient-reported outcomes (PROs) between RSA and total shoulder arthroplasty (TSA) for the treatment of primary GHOA with up to 5-year follow-up and examined temporal trends in the treatment of GHOA between 2012 and 2021.MethodsA retrospective review was performed on patients with primary GHOA undergoing primary arthroplasty surgery from the Surgical Outcomes System global registry between 2012 and 2021. PROs including the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) score, and visual analog scale (VAS) for pain were compared between RSA and TSA at 1, 2, and 5 years postoperatively.ResultsA total of 4451 patients were included, with 2693 (60.5%) undergoing TSA and 1758 (39.5%) undergoing RSA. Both RSA and TSA provided clinically excellent outcomes at 1 year postoperatively (ASES: 80.8 ± 17.9 vs. 85.9 ± 15.2, respectively; SANE: 74.8 ± 24.7 vs. 79.5 ± 22.9; VAS pain: 1.3 ± 2.0 vs. 1.1 ± 1.7; all P < .05) that were maintained at 2 years (ASES: 81.3 ± 19.3 vs. 87.3 ± 14.9; SANE: 74.8 ± 26.2 vs. 79.7 ± 24.7; VAS pain: 1.3 ± 2.1 vs. 1.0 ± 1.6; all P < .05) and 5 years (ASES: 81.7 ± 16.5 vs. 86.9 ± 15.3; SANE: 71.6 ± 28.5 vs. 78.2 ± 25.9; VAS pain: 1.0 ± 1.7 vs. 1.0 ± 1.7; all P < .05), with statistical significance favoring TSA. After controlling for age and sex, there was an adjusted difference of 4.5 units in the ASES score favoring TSA (P = .005) at 5 years postoperatively but no differences in adjusted SANE (P = .745) and VAS pain (P = .332) scores. The use of RSA for GHOA grew considerably over time, from representing only 17% of all replacements performed for GHOA in 2012 to nearly half (47%) in 2021 (P < .001).ConclusionRSA as a treatment for GHOA with an intact rotator cuff seems to yield PROs that are largely clinically equivalent to TSA extending to 5 years postoperatively. The observed statistical significance favoring TSA appears to be of marginal clinical benefit based on established minimal clinically important differences and may be a result of the large sample size. Further research using more granular clinical data and examining differences in range of motion and complications is warranted as it may change the value analysis. 相似文献
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《Vaccine》2016,34(41):5034-5039
BackgroundAs the World Health Organization (WHO) currently recommends that children be protected against 11 different pathogens, it is becoming increasingly necessary to administer multiple injectable vaccines during a single immunization visit. In this study we assess Gambian healthcare providers’ and infant caregivers’ attitudes and practices related to the administration of multiple injectable vaccines to a child at a single immunization visit before and after the 2015 introduction of inactivated polio vaccine (IPV). IPV introduction increased the number of injectable vaccines recommended for the 4-month immunization visit from two to three in The Gambia.MethodsWe conducted a cross-sectional questionnaire-based survey before and after the introduction of IPV at 4 months of age in a representative sample of all health facilities providing immunizations in The Gambia. Healthcare providers who administer vaccines at the selected health facilities and caregivers who brought infants for their 4 month immunization visit were surveyed.FindingsPrior to IPV introduction, 9.9% of healthcare providers and 35.7% of infant caregivers expressed concern about a child receiving more than 2 injections in a single visit. Nevertheless, 98.8% and 90.9% of infants received all required vaccinations for the visit before and after IPV introduction, respectively. The only reason why vaccines were not received was vaccine stock-outs. Infant caregivers generally agreed that vaccinators could be trusted to provide accurate information regarding the number of vaccines that a child needed.ConclusionHealthcare providers and infant caregivers in this resource limited setting accepted an increase in the number of injectable vaccines administered at a single visit even though some expressed concerns about the increase. 相似文献
6.
The extracellular electrophysiological properties of neurons in the laterodorsal tegmental nucleus (LDT), a major source of cholinergic afferents to the thalamus, were studied in chloral hydrate-anesthetized rats. A combination of antidromic activation from the thalamus and histological verification of recording sites was used to correlate the identity of extracellular recordings in the rat LDT with cholinergic neurons in that region. All neurons antidromically activated by stimulation of the anteroventral thalamus were histologically verified to be within clusters of cholinergic (NADPH-d-positive) cells in the LDT or in the adjacent nucleus locus coeruleus (LC). The thalamically projecting LDT neurons had a homogeneous neurophysiological profile consisting of long duration action potentials (mean = 2.5 ms), slow conduction velocities (mean = 0.78 m/s), and lengthy chronaxie values (mean = 0.725 ms). The appearance and axonal characteristics of these neurons resembled those of noradrenergic LC neurons, but the two populations exhibited substantially different spontaneous activity patterns and sensory responsiveness. These characteristics may be useful in the preliminary identification of putative cholinergic neurons in vivo, and thereby provide a foundation for exploring the neuropharmacology, afferent modulation, sensory responsiveness and behavioral correlates of the brainstem cholinergic system. 相似文献
7.
Prediction of steady state bioequivalence relationships using single dose data II-nonlinear kinetics
A J Jackson 《Biopharmaceutics & drug disposition》1989,10(5):489-503
Two nonlinear pharmacokinetic models were simulated to investigate the relationship between single and multiple dose bioequivalency parameters for drugs such as phenytoin and propranolol which exhibit either saturable elimination kinetics or a capacity limited first pass effect. Mean Tmax, Cmax and area under the plasma-concentration time curve values from 0 to infinity (AUC 0-infinity) were compared after a single and multiple dose(s) of a test or reference drug. The aim was to determine if there were systematic changes in the limits of the single dose confidence interval at steady state that would limit the usefulness of confidence intervals following a single dose in accurately predicting bioavailability following multiple dosing. The 90 per cent confidence interval expressed as a percentage of the reference mean for Tmax, Cmax, and AUC 0-infinity showed model dependent changes from single to multiple dosing in response to the level of data error and changes in absorption. Changes in clearance also seemed to have a marked effect on the observed limits of the single and multiple dose confidence intervals especially for Cmax which showed a characteristic change in the intervals as a function of the clearance ratio. The model used to describe phenytoin had confidence intervals for Cmax and AUC 0-infinity from single to multiple dosing that were similar to that seen for the experimental data. However, the model predictions for Tmax confidence intervals following single and multiple dosing was at variance with the experimental data for formulations A and B. 相似文献
8.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure. 相似文献
9.
一阶导数高速脉冲极谱法用于盐酸普鲁卡因的定量分析 总被引:2,自引:0,他引:2
研究了一阶导数高速脉冲极谱法,并运用于盐酸普鲁卡因及其注射制剂的定量分析。在-0.04 V(对 Ag/AgCl)处出现的良好导数峰,于1.0~6.0×10~(-4)mol/L 范围内,导数峰电流与浓度呈线性关系。检测限为3.0×10~(-8)mol/L。操作简便、快速、灵敏,结果准确。 相似文献
10.
目的 探讨肺灌注显像在Ⅲ期非小细胞肺癌(NSCLC)调强放疗(IMRT)保护功能肺的可行性。方法 选择拟行放疗的Ⅲ期NSCLC患者24例,分别行PET-CT和SPECT定位,图像传至治疗计划系统进行图像融合。根据SPECT图像确定功能肺(FL)和非功能肺(NFL),FL是指放射性计数为最大放射性计数的30%以上(包括30%)的区域,其他区域为NFL。肺灌注受损分为4级:0级,无灌注受损;1级,肿瘤及其周围局部肺灌注受损;2级,达1叶肺灌注受损;3级,超过1叶肺灌注受损。根据SPECT图像提供的肺功能信息制定IMRT计划进行优化,尽可能降低FL的照射体积剂量。采用配对t检验统计分析优化前后的IMRT计划的肺组织剂量参数变化。结果 患者均有不同程度的肺灌注缺损,其中肺灌注受损1级8例,2级6例,3级10例。根据SPECT提供的肺功能信息优化IMRT计划后WLV和FLV均有不同程度降低,而FLV降低程度更加明显。优化后WLV10、WLV15、WLV20、WLV25、WLV30和FLV10、FLV15、FLV20、FLV25、FLV30差异有统计学意义。结论 根据SPECT图像提供的肺功能信息优化IMRT计划以保护Ⅲ期NSCLC功能肺是可行的。 相似文献