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71.
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Background:

No data on the incidence of pleural effusion (PE) in Chinese patients with pulmonary embolism are available to date. The aim of the current study was to investigate the frequency of PE in a Chinese population of patients with pulmonary embolism.

Methods:

This was a retrospective observational single-center study. All data of computed tomography pulmonary angiography (CTPA) performed over 6-year period on adult patients with clinically suspected pulmonary embolism were analyzed.

Results:

From January 2008 until December 2013, PE was identified in 423 of 3141 patients (13.5%) with clinically suspected pulmonary embolism who underwent CTPA. The incidence of PE in patients with pulmonary embolism (19.9%) was significantly higher than in those without embolism (9.4%) (P < 0.001). Majority of PEs in pulmonary embolism patients were small to moderate and were unilateral. The locations of emboli and the numbers of arteries involved, CT pulmonary obstruction index, and parenchymal abnormalities at CT were not associated with the development of PE.

Conclusions:

PEs are present in about one fifth of a Chinese population of patients with pulmonary embolism, which are usually small, unilateral, and unsuitable for diagnostic thoracentesis.  相似文献   
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The safety and efficacy of the JXA1-R vaccine, an attenuated strain of highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV), were examined using an intramuscular challenge model in piglets. The JXA1-R vaccine was obtained by passing HP-PRRSV JXA1 through Marc-145 cells (82nd passage). Genomic sequence comparisons showed that strain JXA1-R and its parental strain, JXA1, differ by 47 amino acids, and most of these differences are scattered throughout the PRRSV genome. Four-week-old PRRSV-free piglets were inoculated intramuscularly with JXA1-R vaccine (103.0, 104.0, 105.0, 106.0, and 107.0 50% tissue culture infective doses [TCID50]/ml for groups 1 to 5, respectively) and then challenged intramuscularly with the 5th passage virus of JXA1 virus (JXA1-F5, 3 ml × 104.5 TCID50/ml) 28 days after inoculation. The humoral immune response, swine growth, clinical signs, and differential organ lesions were monitored. The results showed that all vaccinated piglets had a perceptible humoral immune response to vaccination after day 7, which then promptly increased, almost reaching the maximum sample/positive (S/P) ratio value at 28 days postimmunization. Viremia detection indicated that the viral replication levels of the challenge virus in the immunized groups (immunization doses ≥104.0/ml) were significantly lower than that of the virus-challenged unvaccinated control group. Piglets in groups 2 to 5 were effectively protected against lethal HP-PRRSV infection and did not show any obvious changes in body temperature or clinical signs of disease at any point during the experiment. However, two of five piglets in group 1 showed mild pathological lesions and transitory high fever. These results suggest that JXA1-R (TCID50/ml ≥104.0) is sufficiently attenuated and can provide effective protection against the lethal wild-type HP-PRRSV.  相似文献   
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Flavonoids have shown a variety of biological activities such as antimicrobial, antibacterial, antifungal, antiviral, antiinflammatory, antitumor, antiatherogenic, and antihyperglycemic activities. A lot of important flavonoids contain cis-diols such as rutin (Ru), quercetin (Qu), luteolin (Lu), myricetin (Myr) and baicalein (Ba) and so on. It is necessary to establish a simple, low-cost and efficient purification method for cis-diol-containing flavonoids from plant extracts. Boronate affinity materials are able to reversibly bind the cis-diols via boronic acids by forming a five- or six-membered boronic cyclic ester in aqueous media. However, conventional boronate affinity materials have to be used in alkaline media, which can lead to the oxidation of cis-diols in compounds. In this study, the polyethyleneimine (PEI)-assisted 3-carboxybenzoboroxole-functionalized magnetic nanoparticles (MNPs) were prepared to achieve efficient capture of cis-diol-containing flavonoids under neutral conditions. Branched PEI was applied as a scaffold to amplify the number of boronic acid moieties, while 3-carboxybenzoboroxole, exhibiting high affinity and excellent water solubility toward flavonoids, was used as an affinity ligand. The prepared boronate affinity MNPs exhibited high binding capacity and fast binding kinetics (equilibrium in 3 min) under neutral conditions. In addition, the obtained boronate affinity MNPs exhibited high binding affinity (Kd ≈ 10−4 M), low binding pH (pH ≥ 6.0) and tolerance of the interference to abundant sugars.

Flavonoids have shown a variety of biological activities such as antimicrobial, antibacterial, antifungal, antiviral, antiinflammatory, antitumor, antiatherogenic, and antihyperglycemic activities.  相似文献   
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目的探讨平喘益气颗粒联合沙美特罗替卡松气雾剂治疗慢性阻塞性肺疾病稳定期的临床疗效。方法选取2017年6月—2018年6月在天津市黄河医院治疗的94例慢性阻塞性肺疾病稳定期患者为研究对象,将患者按随机数表法分为对照组和治疗组,每组各47例。对照组吸入沙美特罗替卡松吸入气雾剂,2揿/次,2次/d。治疗组在对照组基础上口服平喘益气颗粒,2袋/次,3次/d。两组患者连续治疗3个月。观察两组的临床疗效,比较两组的肺功能指标、SGRQ评分、6 min步行距离、免疫功能、炎症因子。结果治疗后,对照组和治疗组的总有效率分别为76.60%、91.49%,两组比较差异有统计学意义(P0.05)。治疗后,两组第1秒用力呼气容积(FEV1)、用力肺活量(FVC)、FEV1/FVC均显著提高,同组治疗前后比较差异有统计学意义(P0.05);且治疗后治疗组FEV1、FVC、FEV1/FVC明显高于对照组,差异有统计学意义(P0.05)。治疗后,两组圣乔治呼吸问卷(SGRQ)评分显著降低,6 min步行距离显著增加,同组治疗前后比较差异有统计学意义(P0.05);且治疗后治疗组SGRQ评分低于对照组,6 min步行距离长于对照组,差异有统计学意义(P0.05)。治疗后,治疗组CD3~+、CD4~+、CD4~+/CD8~+明显高于治疗前,且治疗组CD3~+、CD4~+、CD4~+/CD8~+明显高于对照组,差异有统计学意义(P0.05)。治疗后,两组肿瘤坏死因子-α(TNF-α)、白细胞介素-8(IL-8)水平显著下降,同组治疗前后比较差异有统计学意义(P0.05);且治疗后治疗组炎症因子水平明显低于对照组,差异有统计学意义(P0.05)。结论平喘益气颗粒联合沙美特罗替卡松气雾剂治疗慢性阻塞性肺疾病稳定期具有较好的临床疗效,可改善患者临床症状及肺功能,调节免疫功能及相关炎症因子,提高生活质量,具有一定的临床推广应用价值。  相似文献   
80.
Genetic variation in the IL-7 receptor-α (IL-7R) gene is associated with susceptibility to human type 1 diabetes (T1D). Here we investigate the therapeutic efficacy and mechanism of IL-7Rα antibody in a mouse model of T1D. IL-7Rα antibody induces durable, complete remission in newly onset diabetic mice after only two to three injections. IL-7 increases, whereas IL-7Rα antibody therapy reduces, the IFN-γ-producing CD4(+) (T(H)1) and IFN-γ-producing CD8(+) T cells. Conversely, IL-7 decreases and IL-7Rα antibody enhances the inhibitory receptor Programmed Death 1 (PD-1) expression in the effector T cells. Programmed Death 1 blockade reversed the immune tolerance mediated by the IL-7Rα antibody therapy. Furthermore, IL-7Rα antibody therapy increases the frequency of regulatory T cells without affecting their suppressor activity. The durable efficacy and the multipronged tolerogenic mechanisms of IL-7Rα antibody therapy suggest a unique disease-modifying approach to T1D.  相似文献   
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