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目的探讨内窥镜获取大隐静脉在冠状动脉旁路移植术中的应用并探讨学习曲线，重点关注初学者易发生的问题及对早期临床结果的影响。方法回顾性分析2013年7月至2014年4月在郑州大学第一附属医院心外科接受不停跳冠状动脉旁路移植术并使用内窥镜技术获取大隐静脉的83例患者的临床资料，按照手术时间的先后顺序分为A组（初学组20例）、B组（熟悉组20例）、C组（进步组20例）、D组（成熟组23例），分析各组之间患者围术期及随访结果差异，明确学习曲线周期。结果该组患者年龄为（60.22±8.06）岁，体质量为（69.77±11.66） kg，其中合并高血压24例、糖尿病26例、亚急性脑梗14例。A组相对于后三组获取大隐静脉长度与时间比值明显较小（PP=0.006），并且随访1年时静脉桥通畅率较低，但差异无统计学意义。结论内窥镜获取大隐静脉之前技术操作培训是必要的，能有效规避初学者造成的血管损伤，实际获取的过程中大概需要亲自操作20例，并认真总结技术技巧就可以较为熟练地进行相关操作。

Objective To investigate the effect of f fine nursing management for patients undergoing simultaneous bilateral lobectomy. Methods Totally 52 patients under simultaneous bilateral lobectomy were randomly divided into the control group and observation group, with 26 cases in each group. The control group received routine nursing interventions during perioperative period. The observation group was given fine nursing management. The indwelling time of catheter, length of postoperative hospital stay, hospitalization costs and postoperative complications were recorded. Results The indwelling time of drainage tube and length of postoperative hospital stay in the observation group were shorter than those in the control group(P＜0. 05). There was a case of pneumothorax, 1 case of stage I pressure injury, 5 cases of arrhythmia, 2 cases of breathing difficulties and 2 cases of incision infection in the observation group. There was a case of pneumothorax, 3 cases of stage I pressure injury, 5 cases of arrhythmia, 1 case of breathing difficulties, 5 cases of incision infection and 1 case of death in the control group. Conclusion Implementation of fine nursing management is effective to shorten indwelling time of drainage tube and length of postoperative hospital stay of patients undergoing simultaneous bilateral lobectomy. (目的 探讨同期双侧肺叶切除围手术期实施精细化护理干预的效果。方法 选取2015年1月—2021年12月医院收治的行同期双侧肺叶切除患者52例, 随机分为对照组和观察组, 各26例。对照组围手术期采取常规护理, 观察组围术期采取精细化护理干预。记录和分析两组患者引流管留置时间、术后平均住院日、住院费用和术后并发症。结果 观察组患者引流管留置时间、术后平均住院日较对照组缩短, 差异有统计学意义(P＜0. 05)。观察组术后发生气胸1例, I期压疮1例, 心律失常5例, 呼吸困难2例, 切口感染2例; 对照组术后气胸1例, I期压疮3例, 心律失常5例, 呼吸困难1例, 切口感染5例, 死亡1例。结论 同期双侧肺叶切除围手术期实施精细化护理干预, 能缩短患者引流管留置时间和术后平均住院日, 对促进患者术后康复具有积极意义。)

目的基于不同阶段COVID-19患者肺部病变变化，利用CT影像学特征建立列线图模型，探讨其预测病变是否进展的效能。方法对136例新冠肺炎患者进行回顾性研究，均经2次以上CT扫描。这些患者数据被分成三个队列（训练队列，以及验证队列1和2）。训练队列中的患者根据发热症状开始至首次CT的时间分为三组，分析比较各组之间临床表现和CT特征。根据患者的CT特征构建了一个预测疾病进展的列线图，并对其性能进行了评估。结果训练队列包括41名患者。根据三个CT特征：不规则条索影、充气支气管征和不规则形态病灶的比例≥50%，生成了预测疾病进展的列线图，AUC（95%CI）=0.906（0.817，0.995）。训练队列的C指数为0.906，内部验证的C指数为0.892。验证队列1（34例）： AUC（95%CI）=0.889（0.793，0.984）；验证队列2（61例）： AUC（95%CI）=0.876（0.706，1.000）。校准曲线表明，列线图预测值与观测值具有较好的一致性。结论基于CT影像组学建立的列线图模型可以预测患者肺部病灶的转归，具有较高的敏感性和特异性。根据新冠肺炎患者的CT影像特征变化，即当出现不规则条索影、充气支气管征和不规则形态病灶的比例≥50%时，肺部病灶将会得到改善。

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Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A yeast two-hybrid cDNA library of cucumber was constructed by Gateway technology under the stress of Pseudoperonospora cubensis and Corynespora cassiicola using the disease resistant inbred line D9320. The results showed that the number of yeast library clones was 350, the titer of library was 3.5×107 CFU/mL and the rate of recombination was 100%. The length of all the fragments was 750-2 000 bp. The average length was more than 1 000 bp. The yeast two hybrid cDNA library of cucumber under the stress of Pseudoperonospora cubensis and Corynespora cassiicola was constructed successfully, which could be used for screening interaction proteins of the double-disease resistance mechanism in cucumber. [ABSTRACT FROM AUTHOR]

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Objective: To investigate the impacts of galangin (Gal) on the immune inflammatory response in preeclampsia (PE) rats by regulating the IL-6/signal transducer and activator of transcription 3(STAT3) signaling pathway. Methods: Pregnant rats were injected subcutaneously with L-arginine methyl ester (L-NAME 125 mg/kg) to establish a PE model. After successful modeling, they were randomly grouped into Model group, low, medium and high doses Gal groups (10, 30, and 60 mg/kg) and activator group (60 mg/kg Gal+0.05 mg/kg IL-6/STAT3 pathway activator rIL-6). Twelve pregnant rats of the same period were randomly selected as the control group, and each group was given corresponding drugs by gavage and intraperitoneal injection, once a day for a continuous week. The levels of mean caudal artery pressure (MAP) and 24-hour urinary protein and blood urea nitrogen (BUN) in rats during the third trimester of pregnancy were measured using a blood pressure tester and a fully automated biochemical analyzer; the number and weight of the average offspring of pregnant mice in each group were calculated, and the pregnancy outcome was analyzed; HE staining was applied to observe the pathological damage of rat placenta; ELISA was applied to detect the levels of IL-6, IL-1β and TNF-α in the placenta of rats in each group; the proportion of T lymphocytes in rat peripheral blood was detected by flow cytometry; Western blot was applied to detect the expression of IL-6/STAT3 pathway protein in rat placenta. Results: Compared with control group, the levels of MAP, 24-hour urinary protein, BUN, IL-6, IL-1β, TNF-α, the CD8+T cells, and the expression levels of IL-6 and p-STAT3/STAT3 proteins in Model group were obviously increased, the placenta tissue was severely damaged, the mean offspring number and mean offspring weight, the proportions of CD3+T, CD4+T, and CD4+/CD8+T cells were decreased (P<0.05); compared with Model group, the levels of MAP, 24-hour urinary protein, BUN, IL-6, IL-1β, TNF-α, the CD8+T cells, and the expression levels of IL-6 and p-STAT3/STAT3 proteins in Gal low, medium and high doses groups were obviously decreased, the damage to placental tissue was reduced, the mean offspring number and mean offspring weight, the proportions of CD3+T, CD4+T, and CD4+/CD8+T cells were increased(P<0.05); compared with Gal high-dose group, the levels of MAP, 24-hour urinary protein, BUN, IL-6, IL-1β, TNF-α, the CD8+T cells, and the expression levels of IL-6 and p-STAT3/STAT3 proteins in activator group were obviously increased, the placenta tissue was aggravated, the mean offspring number and mean offspring weight, the proportions of CD3+T, CD4+T and CD4+/CD8+T cells were decreased (P<0.05). Conclusion: Gal may play a role in alleviating PE symptoms and improving pregnancy outcomes by inhibiting the IL-6/STAT3 pathway, inhibiting inflammatory reactions, and regulating cellular immunity. [ABSTRACT FROM AUTHOR]

Hanging silt curtains are commonly used in dredging projects as a pollution control measure to prevent the spread of suspended sediments and protect adjacent habitats. Based on the expansion project of the entrance channel in the Donglian operation area of Huizhou Port, a study was conducted to evaluate the layered pollution prevention effects of hanging silt curtains. Through on-site measurements of sediment concentration around the hanging silt curtains and sampling of suspended sediment, the temporal changes in the layered pollution prevention effects and the plane distribution of the overall pollution control effects were summarized. The research findings indicate that the pollution prevention effects of the upper and middle layers of the silt curtain are greater than 0, with the middle layer showing a significantly stronger effect than the upper layer, thus providing positive pollution control. In contrast, the pollution prevention effects of the bottom layer is less than 0, with increased concentrations of suspended sediment. During the operational period of the dredging vessel, as lateral sediment transport increases, the pollution prevention efficacy in the upper and middle layers reaches its peak, while the negative effects in the bottom layer also peak. At the same time, the pollution prevention effects show a significant positive correlation with flow velocity, and the influence of the silt curtain leads to noticeable differences in sediment grain size in the upstream and downstream lateral flow. Overall, the effectiveness of the hanging silt curtain is characterized by higher sediment concentrations on the protected side compared to the unprotected side, resulting in a net negative pollution prevention effect. From a holistic perspective, the net pollution prevention effect of the middle section of the curtain is less negative than that of the two sides. These results can provide reference for selecting pollution control measures and designing the parameter design and layout of hanging silt curtains. [ABSTRACT FROM AUTHOR]

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将提取纯化的南瓜籽甾醇作用于丙酸睾酮诱导构建的前列腺增生大鼠模型，研究其对大鼠前列腺增生及抗氧化能力的影响。将50只雄性SD大鼠分为对照组，模型组，南瓜籽甾醇高、中、低剂量组，实验结束后分别测定其前列腺湿重、前列腺指数（PI）、前列腺酸性磷酸酶（PACP）活性及抗氧化指标中的总抗氧化能力（T-AOC）水平、超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量，同时对前列腺组织形态进行切片观察。结果表明：与模型组相比，南瓜籽甾醇高剂量组的前列腺湿重、PI、PACP活性与MDA含量显著降低，并且南瓜籽甾醇中、高剂量组的T-AOC水平、SOD活性显著升高。以上指标的变化均呈现出南瓜籽甾醇高剂量组优于中剂量组的趋势。同时，与模型组相比，南瓜籽甾醇中、高剂量组大鼠前列腺组织细胞受损状况均有所改善，南瓜籽甾醇高剂量组的改善效果更明显。因此，南瓜籽甾醇在一定程度上具有改善大鼠前列腺增生及提高大鼠前列腺组织的抗氧化能力的作用。 The extracted and purified pumpkin seed sterol was used to feed the rats with benign prostate hyperplasia induced by testosterone propionate to study its effect on the benign prostate hyperplasia and antioxidant capacity of rats. 50 Male SD rats were divided into control group, model group, high, medium and low dose groups of pumpkin seed sterol. After the experiment, the prostate wet weight, prostate index (PI), and levels of prostatic acid phosphatase (PACP), total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured, the morphology of prostate tissue was observed simultaneously. The results showed that compared with the model group, the wet weight, PI, PACP activities, and MDA content of the high dose group of pumpkin seed sterol significantly decreased, and the T-AOC level and SOD activity in the midium and high dose groups of pumpkin seed sterol significantly increased. All of the above changes showed a trend of high dose group of pumpkin seed sterol better than medium dose group. At the same time, the prostate tissue cell damages of rats in medium and high dose groups of the pumpkin seed sterol were improved compared with the model group, and high dose group of the pumpkin seed sterol had the most obvious effect. This indicated that pumpkin seed sterol improved the prostate hyperplasia in rats to some extent and improved the antioxidant capacity of rat prostate tissue.

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Under the background of the rural revitalization strategy, the development of new agricultural business entities has ushered in unprecedented policies and opportunities of The Times. As the main form of new agricultural management, farmers' specialized cooperatives are also the inevitable choice and effective carrier of rural revitalization strategy. In recent years, under the guidance of the market economy system, various regions have set up cooperatives in rural areas to drive the development of agricultural industry according to their local conditions and resource endowments and geographical advantages. Taking Alar City of the First Division as an example, this paper conducted questionnaire survey and field interview on farmers' cooperatives, adopted binary Logistic regression model to empirically study the factors affecting the high-quality development of farmers' cooperatives under the background of rural revitalization, and finally drew conclusions based on the regression results and put forward corresponding countermeasures and suggestions, hoping to provide certain references for the high-quality development of farmers' cooperatives. [ABSTRACT FROM AUTHOR]

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This study analyzes the impact of changes in Beijing’s grain consumption structure on food security from 2016 to 2021. The results show that from 2016 to 2021, the total grain consumption in Beijing showed a fluctuating decline. Under the influence of the “transfer regulation” of agriculture in Beijing and the impact of the COVID-19 epidemic, urban and rural residents increased the hoarding of rations, making the indirect grain consumption stable. With the acceleration of the urbanization process and the development of the special action of “relieving and promoting improvement”, the dislocation between the upgrading of food consumption demand and the reduction of food production of urban and rural residents in Beijing has led to an increase in food insecurity. In order to ensure food security and promote the high-quality development of Beijing’s grain industry, it is proposed to strengthen scientific and technological empowerment and steadily increase the grain self-sufficiency rate; strengthen the coordination mechanism to ensure the supply of food in the capital; promote the integration of planting and breeding and develop ecological circular agriculture. [ABSTRACT FROM AUTHOR]

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In view of the fracture and edge crack initiation of the bogie cowcatcher during the service of a metro train,the failure causes are analyzed,and a fatigue performance evaluation method combining finite element analysis and dynamic stress test is proposed to verify the rationality of improving the structural design of the cowcatcher.Firstly,the structure of the cowcatcher with fracture or edge crack is analyzed in the aspects of design,structure,manufacturing and raw materials,and the corresponding structural improvement scheme is proposed.Secondly,the static strength and fatigue strength of the structure for the new cowcatcher are analyzed to clarify the dangerous parts according to the EN13749 standard.Thirdly,determine the strain gauge layout plan and conduct line tests considering the simulation analysis results and the operating space comprehensively.Finally,the fatigue performance evaluation of the cowcatcher is carried out by miner’s linear cumulative damage rule and IIW recommended S-N curve.The results show that the fatigue performance of the new type of cowcatcher based on finite element analysis and dynamic stress test meet the requirements,and the two support each other to further verify the rationality of the new structure design.Simultaneously,the simulation analysis results provide a theoretical reference for the reasonable arrangement of measuring points.