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51.
Yong Tan Shuaiyao Lu Bo Wang Xuewen Duan Yunkai Zhang Xiaozhong Peng Hangwen Li Ang Lin Zhenzhen Zhan Xingguang Liu 《Journal of medical virology》2023,95(1):e28161
Messenger RNA (mRNA) vaccines are promising alternatives to conventional vaccines in many aspects. We previously developed a lipopolyplex (LPP)-based mRNA vaccine (SW0123) that demonstrated robust immunogenicity and strong protective capacity against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in mice and rhesus macaques. However, the immune profiles and mechanisms of pulmonary protection induced by SW0123 remain unclear. Through high-resolution single-cell analysis, we found that SW0123 vaccination effectively suppressed SARS-CoV-2-induced inflammatory responses by inhibiting the recruitment of proinflammatory macrophages and increasing the frequency of polymorphonuclear myeloid-derived suppressor cells. In addition, the apoptotic process in both lung epithelial and endothelial cells was significantly inhibited, which was proposed to be one major mechanism contributing to vaccine-induced lung protection. Cell−cell interaction in the lung compartment was also altered by vaccination. These data collectively unravel the mechanisms by which the SW0123 protects against lung damage caused by SARS-CoV-2 infection. 相似文献
52.
Alfentanil co-induction for laryngeal mask insertion 总被引:1,自引:0,他引:1
We assessed the effect of two different doses of alfentanil (5 and 10 micrograms.kg-1) on the conditions for laryngeal mask airway insertion in ASA 1 and 2 patients who received propofol for induction of anaesthesia. One hundred and fifty unpremedicated patients were randomly allocated to receive either propofol 2.5 mg.kg-1 only (Group P), alfentanil 5 micrograms.kg-1 and propofol 2.5 mg.kg-1 (Group A5), or alfentanil 10 micrograms.kg-1 and propofol 2.5 mg.kg-1 (Group A10). The addition of alfentanil to propofol resulted in a greater ease of insertion and a better quality of airway patency. Pretreatment with alfentanil also resulted in a significantly higher success rate during the first attempt at inserting the laryngeal mask airway compared with Group P (Group P 58%, Group A5 96%, Group A10 94%). Patients in Group P were apnoeic for a mean (+/- SD) time of 3.3(+/- 1.9) min, 4.71 (+/- 2.2) min in Group A5, and 7.32(+/- 4.3) min in Group A10. The use of alfentanil 10 micrograms.kg-1 with propofol, however, led to a significant decrease in mean arterial pressure and heart rate. We concluded that pretreatment with intravenous alfentanil 5 micrograms.kg-1 prior to propofol provides excellent conditions for insertion of laryngeal mask with minimal adverse haemodynamic changes. 相似文献
53.
54.
黄体酮β-环糊精包合物的研制 总被引:4,自引:0,他引:4
目的:制备黄体酮β-环糊精包合物,并考察其有关性质。方法:采用共沉淀法制备黄体酮β-环糊精包合物。结果:经红外光谱鉴定表明,黄体酮与β-环糊精已形成包合物。结论:黄体酮β-环糊精包合物可明显提高黄体酮的溶解度及溶出速率。 相似文献
55.
头孢替唑钠与头孢唑啉钠对照治疗急性细菌性感染130例 总被引:10,自引:0,他引:10
目的:观察头孢替唑钠治疗急性细菌性感染的疗效及安全性。方法:130例急性呼吸道及泌尿道感染患者,随机分成试验组和对照组。分别接受头孢替唑钠和头孢唑啉钠,均用2g溶于5%葡萄糖溶液或生理氯化钠溶液中静滴,bid,疗程7-14d。结果:试验组痊愈率66.7%,明显优于对照组(P<0.01),总有效率试验组97.0,优照组无明显差异(P>0.05)。头孢替唑钠对106株致病菌的敏感率96%(102/106株高敏),对金葡球菌MIC值为0.06-0.5mg.L^-1,低于头孢唑啉、头孢氨苄,头孢呋辛及头孢他啶的MIC值。结论:头孢替唑钠是治疗急性呼吸道及泌尿道感染安全有效的抗生素。 相似文献
56.
Loss of Fhit expression in head and neck squamous cell carcinoma and its potential clinical implication. 总被引:12,自引:0,他引:12
Shyh-Kuan Tai Janet I Lee K Kian Ang Adel K El-Naggar Khaled A Hassan Diane Liu J Jack Lee Hening Ren Waun K Hong Li Mao 《Clinical cancer research》2004,10(16):5554-5557
PURPOSE: Abnormalities of FHIT, a candidate tumor suppressor gene, have frequently been found in multiple malignancies, including head and neck squamous cell carcinoma (HNSCC). To define its role in HNSCC treated with surgery and postoperative radiotherapy (PORT), the Fhit protein expression status was investigated in 80 patients enrolled in a prospective Phase III clinical trial addressing the dose and fractionation regimen of PORT. EXPERIMENTAL DESIGN: Immunohistochemical staining of HNSCC tissue sections for Fhit expression was performed. The Fhit expression status was correlated with the clinicopathological characteristics and clinical course. The median follow-up duration was 4.9 years. RESULTS: Loss of Fhit expression was found in 52 of the 80 study patients (65%). There was not a significant association between Fhit expression and clinical characteristics. Patients whose tumor exhibited negative Fhit expression had a significantly worse 5-year overall survival duration [hazard ratio = 0.49; 95% confidence interval, 0.23-1.03; P = 0.05 (log-rank test)] than did those whose tumor exhibited positive Fhit expression. One third of the patients with a Fhit-negative tumor had distant metastasis during the follow-up period. Paradoxically, patients classified as high risk who had a Fhit-negative tumor experienced locoregional recurrence less often (18%) than did high-risk patients who had a Fhit-positive tumor (33%). CONCLUSIONS: Loss of Fhit expression is a poor prognostic indicator in patients with HNSCC. However, tumors lacking Fhit expression may be more sensitive to PORT and therefore more susceptible to locoregional control. 相似文献
57.
CT-based delineation of lymph node levels and related CTVs in the node-negative neck: DAHANCA, EORTC, GORTEC, NCIC,RTOG consensus guidelines. 总被引:25,自引:0,他引:25
Vincent Grégoire Peter Levendag Kian K Ang Jacques Bernier Marijel Braaksma Volker Budach Cliff Chao Emmanuel Coche Jay S Cooper Guy Cosnard Avraham Eisbruch Samy El-Sayed Bahman Emami Cai Grau Marc Hamoir Nancy Lee Philippe Maingon Karin Muller Hervé Reychler 《Radiotherapy and oncology》2003,69(3):227-236
BACKGROUND AND PURPOSE: The appropriate application of 3-D CRT and IMRT for HNSCC requires a standardization of the procedures for the delineation of the target volumes. Over the past few years, two proposals--the so-called Brussels guidelines from Grégoire et al., and the so-called Rotterdam guidelines from Nowak et al.--emerged from the literature for the delineation of the neck node levels. Detailed examination of these proposals however revealed some important discrepancies. MATERIALS AND METHODS: Within this framework, the Brussels and Rotterdam groups decided to review their guidelines and derive a common set of recommendations for delineation of neck node levels. This proposal was then discussed with representatives of major cooperative groups in Europe (DAHANCA, EORTC, GORTEC) and in North America (NCIC, RTOG), which, after some additional refinements, have endorsed them. The objective of the present article is to present the consensus guidelines for the delineation of the node levels in the node-negative neck. RESULTS AND CONCLUSIONS: First a short discussion of the discrepancies between the previous Brussels and the Rotterdam guidelines is presented. The general philosophy of the consensus guidelines and the methodology used to resolve the various discrepancies are then described. The consensus proposal is then presented and representative CTVs that are consistent with these guidelines are illustrated on CT sections. Last, the limitations of the consensus guidelines are discussed and some concerns about the direct applications of these guidelines to the node-positive neck and the post-operative neck are described. 相似文献
58.
59.
We report an unusual case of focal nodular hyperplasia (FNH) occurring in a 19-month-old female without a typical central fibrous scar. Ultrasound demonstrated a solid, hypoechoic, highly vascular mass situated in the left lobe of the liver. Computed tomography showed a solid mass with no evidence of a central fibrous scar. A hepatic angiogram demonstrated enlarged right and left hepatic arteries supplying the vascular tumour, with early venous drainage into the inferior vena cava; a feature which has not been previously described. Surgical resection was carried out and a solid, nodular tumour measuring 9 x 4 x 4 cm was removed. The diagnosis of FNH was made histologically. The characteristic imaging findings of FNH will be discussed and a review of the literature of FNH in children will be presented. 相似文献
60.
肿瘤转移是一个复杂的、多步骤的、肿瘤细胞和宿主细胞相互作用的过程,是恶性肿瘤的重要生物学行为,往往是导致病人死亡的直接原因。随着分子生物学的发展,对肿瘤转移抑制的研究已进入分子水平,nm23基因即是近年来发现并被证实与多种肿瘤的转移有关的较新的肿瘤抑制基因,该基因可能通过影响细胞内微管的聚合/解聚和G蛋白介导的信号传导,而参与肿瘤的发生和发展。 相似文献