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1.
Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT 03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.  相似文献   
2.
目的 探讨右美托咪定联合综合体温保护对腔镜手术治疗老年恶性肿瘤患者苏醒期质量及免疫功能的影响。方法 选择择期行腔镜手术治疗的老年恶性肿瘤患者90例,随机均分为3组:对照组(C组)、体温保护组(T组)和体温保护联合右美托咪定组(T-D组),每组30例。C组常规体温保护,T组和T-D组综合体温保护;T-D组麻醉诱导前10 min泵注右美托咪定0.5 μg/kg。记录3组患者麻醉诱导开始时(T0)、手术开始30 min(T1)、60 min(T2)、90 min(T3)、120 min(T4)以及手术结束时(T5)的鼻咽温度;于T0、术后2 h(T6)、24 h(T7)和48 h(T8)时抽取静脉血标本,测定T淋巴细胞亚群(CD3+、CD4+和CD8+)和自然杀伤细胞(NK cell)水平;记录患者术中麻醉药物用量及苏醒期质量指标。结果 与T0比较,C组T2~T5时点鼻咽温度均明显降低(P < 0.05);与C组比较,T组和T-D组T2~T5时点鼻咽温度明显升高(P < 0.05)。与T0时点比较,C组、T组和T-D组T6、T7和T8时点CD3+和NK cell活性均明显降低(P < 0.05);C组在T6、T7和T8时点,T组和T-D组在T6和T7时点,CD4+活性均明显降低(P < 0.05)。与C组比较,T组和T-D组T6和T7时点CD3+细胞活性均明显升高(P < 0.05);T组在T7时点,T-D组在T6和T7时点,CD4+细胞活性均明显升高(P < 0.05);T组在T7时点,T-D组在T6、T7和T8时点,NK cell活性均明显升高(P < 0.05)。结论 采用体温保护措施联合右美托咪定能够维持老年恶性肿瘤患者的体温稳定,减少围手术期意外低体温(IPH)的发生,并有效提高患者苏醒期质量,减轻免疫抑制程度,加速患者早期恢复。  相似文献   
3.
Background: Considering the poor prognosis of non-small cell lung cancer (NSCLC), the objective of this study was to examine the potential of plasma-derived vesicles as a source of lung cancer-specific proteins. Extracellular vesicle (EV) cargos are specific to the source cells, hence they have the potential of being a source of cancer-specific proteins.  Methods: The proteins differently expressed in cancer were determined and derived from EVs isolated from the plasma of NSCLC patients at the National Lung Hospital. To this end, purification was done using gel filtration chromatography and ultracentrifugation. In addition, nano liquid chromatography mass spectrometry (LC–MS/MS) was used for analyzing. Results: Fifty-seven EV-derived proteins related to NSCLC were highlighted in this research. Some of them have not been addressed before, such as EEF1A1 (elongation factor 1-α1), KPNB1 (Importin subunit beta 1), SRC (proto-oncogene tyrosine-protein kinase) and ACTC1 (actin, alpha cardiac muscle 1). This list was further confirmed through a comparison with ExoCarta and Vesiclepedia. Conclusion: This study is the first work to show the involvement of several novel proteins of small EV (EEF1A1, KPNB1, SRC, and ACTC1) in the progression of NSCLC. The results suggested that they could serve as novel biomarkers for non-small cell lung cancer in the future.  相似文献   
4.
Moderate sedatives have been increasingly used to improve patient comfort during flexible bronchoscopy (FB). However, routine use of moderate sedation during FB is controversial because its efficacy and safety are not well established.This study aims to evaluate the efficacy and safety of moderate sedation during FB.A search was made of Medline, EMBASE, and the Cochrane Library to May 2014.Randomized controlled trials (RCTs) and quasi-RCTs were included.The main analysis was designed to examine the efficacy of moderate sedation during FB in sedation than no-sedation.The willingness to repeat FB was significantly more in sedation than no-sedation (odds ratio [OR] 2.30; 95% confidence interval [CI] 1.11–4.73; P = 0.02; I2 = 22.5). The duration of FB was shorter in sedation group than no-sedation group (standardized mean difference [SMD] −0.21; 95% CI −0.38 to −0.03; P = 0.02; I2 = 78.3%). Event of hypoxia was not significantly different between sedation and no-sedation groups (OR 0.86; 95% CI 0.42–1.73; P = 0.67; I2 = 0%). The SpO2 during procedure was not different between sedation and no-sedation groups (SMD −0.14; 95% CI −0.37 to 0.08; P = 0.21; I2 = 49.9%). However, in subgroup analysis without supplemental oxygen, the SpO2 was significantly lower in sedation than no-sedation group (SMD −0.45; 95% CI −0.78 to −0.11; P = 0.01; I2 = 0.0%).According to this meta-analysis, moderate sedation in FB would be useful in patients who will require repeated bronchoscopies as well as safe in respiratory depression. To our knowledge, although the various sedative drugs are already used in the real field, this analysis was the first attempt to quantify objective results. We anticipate more definite and studies designed to elucidate standardized outcomes for moderate sedation in FB.  相似文献   
5.
6.
儿童哮喘的发病率逐年上升.基于卫生假说,抗生素使用可能减少了微生物暴露,从而增加了过敏性疾病发生的风险.近十年来,就早期抗生素暴露与儿童哮喘的关系进行的大量的流行病学调查的结果并不一致.大多数回顾性研究发现正相关联系,但前瞻性研究未发现联系或联系强度较弱.逆向因果和指示混淆可部分解释两者的关系,但也难以否定因果关系的存在.  相似文献   
7.
Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.  相似文献   
8.
9.
目的调查门诊和普通病房电脑鼠标不同时段的细菌污染情况。方法随机抽取某院门诊及普通病房的各16个电脑鼠标,分别于8∶00、10∶30、13∶00、15∶30进行采样,样本接种培养后对菌落计数并筛查多重耐药菌。结果32个鼠标共计采样128次,最高菌落数达121 CFU/cm2,平均菌落数为23.9 CFU/cm2。随着时间的推移,同一鼠标的细菌计数逐渐增多。不同时段门诊和病房的电脑鼠标菌落数比较,在10∶30、13∶00、15∶30三个时间点,病房鼠标的菌落数均高于门诊(均P≤0.05)。64个病房电脑鼠标标本中检出耐甲氧西林金黄色葡萄球菌(MRSA)和耐碳青霉烯类鲍曼不动杆菌(CRAB)各1株。结论加强鼠标日常清洁消毒及监测工作非常重要,应增加清洁消毒频率或更换长效消毒剂,加强病房环境的清洁消毒。  相似文献   
10.
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