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151.
152.
Narrow gap laser welding (NGLW) is a common solution for the welding of thick structures. NGLW was carried out on narrow-gap butt joints of 40 mm-thick Ti-6Al-4V alloy plates with a U-shaped groove. The distribution characteristics of the interlaminar microstructure in different height ranges of the joint were investigated, and the evolution behavior and formation mechanism of the interlaminar microstructure of the joint were also revealed. This showed that a large amount of short needle martensite nucleated and grew up near the fusion line and the upper boundary of the remelting zone. The “softening” phenomenon occurred in all welds except the cover layer weld. The microstructure evolution and defect migration, induced by multiple welding thermal cycles in the upper weld forming process, were the main reasons for the “softening” of the lower weld. The tensile strength of each sample changed in the range of 920~990 MPa; the fracture mode of the sample belongs to a transgranular ductile fracture. In addition, compared with the upper part of the joint, the plasticity and toughness of the weld area in the lower part of the joint was improved.  相似文献   
153.
Background and AimsPatients with severe fever with thrombocytopenia syndrome (SFTS) commonly show liver function impairment. This study aimed to characterize the liver function indices in SFTS patients and investigate their association with mortality.MethodsClinical information and laboratory results of 459 laboratory-confirmed SFTS patients, including 78 deceased and 381 surviving patients, were retrospectively analyzed. To explore the infectivity of SFTS caused by novel Bunyavirus (SFTSV) in hepatocytes, Huh7 human hepatoma cells were infected with various concentrations of SFTSV in vitro.ResultsThe proportion of SFTS patients developing liver injury during hospitalization was 73.2% (336/459); the hepatocellular injury was the predominant type. The median time to occurrence of liver injury from disease onset was 8 d. Liver injury in the deceased group occurred earlier than that in the surviving group. Alanine aminotransferase (ALT) level between 2–5 times upper limit of normal (ULN) at 4–6 d and between 5–15 ULN at 7–12 d of disease course were independent predictors of mortality. Alkaline phosphatase (ALP) >2 ULN at 7–9 d and elevated ALP at 10–12 days after disease onset were risk factors for death. ALT and aspartate transaminase (AST) levels were correlated with lymphocyte count and platelet-to-lymphocyte ratio (PLR). Total bilirubin (TB), ALT, AST levels showed positive correlation with viral load. In the in vitro experiment, SFTSV infected and replicated inside Huh7 cells.ConclusionsLiver injury is common in SFTS patients. ALT and ALP were independent predictors of SFTS-related mortality. Frequent monitoring and evaluation of liver function indices are needed for SFTS patients.  相似文献   
154.
RNA binding proteins (RBPs) play pivotal roles in breast cancer (BC) development. As an RBP, Processing of precursor 7 (POP7) is one of the subunits of RNase P and RNase MRP, however, its exact function and mechanism in BC remain unknown. Here, we showed that expression of POP7 was frequently increased in BC cells and in primary breast tumors. Upregulated POP7 significantly promoted BC cell proliferation in vitro and primary tumor growth in vivo. POP7 also increased cell migration, invasion in vitro, and lung metastasis in vivo. Through RNA immunoprecipitation coupled with sequencing (RIP‐seq), we found that POP7 bound preferentially to intron regions and POP7‐binding peak associated genes were mainly enriched in cancer‐related pathways. Furthermore, POP7 regulated Interleukin Enhancer Binding Factor 3 (ILF3) expression through influencing its mRNA stability. Knockdown of ILF3 significantly impaired the increased malignant potential of POP7‐overexpressing cells, suggesting that POP7 enhances BC progression through regulating ILF3 expression. Collectively, our findings provide the first evidence for the important role of POP7 and its regulation of ILF3 in promoting BC progression.  相似文献   
155.
Fusobacterium nucleatum infection plays vital roles in colorectal cancer (CRC) progression. Overexpression of microRNA‐4717‐3p (miR‐4717) was reported to be upregulated in F. nucleatum positive CRC tissues, however, the underlying mechanism is unknown. In this study, we found that miR‐4717 promoted CRC cell proliferation in vitro and growth of CRC in vivo following F. nucleatum infection. MicroRNA‐4717 suppressed the expression of mitogen‐activated protein kinase kinase 4 (MAP2K4), a tumor suppressor, by directly targeting its 3′‐UTR. Furthermore, we confirmed that methyltransferase‐like 3 (METTL3)‐dependent m6A methylation could methylate primary (pri)‐miR‐4717, which further promoted the maturation of pri‐miR‐4717, and METTL3 positively regulated CRC cell proliferation through miR‐4717/MAP2K4 pathways. In conclusion, F. nucleatum‐induced miR‐4717 excessive maturation through METTL3‐dependent m6A modification promotes CRC cell proliferation, which provides a potential therapeutic target and diagnostic biomarker for CRC.  相似文献   
156.
BackgroundImmunotherapy is a promising novel treatment for esophageal cancer (ESCA). However, previous studies provide limited direct information about the prognostic significance of immune-related genes (IRGs) in primary ESCA development. This study explored the prognostic value of IRGs and infiltrating tumor immune cells in primary ESCA.MethodsThe ribonucleic acid (RNA)-sequencing data and clinical information of primary ESCA were downloaded from The Cancer Genome Atlas (TCGA) database. Which included the clinical factors and prognosis outcomes of the ESCA patients. The IRGs were downloaded from the ImmPORT database.ResultsWe established the robust IRG prognostic signature of 4 IRGs (i.e., heat shock protein family A member 6, Oncostatin M, androgen receptor, and nuclear receptor subfamily 2 group F member 2) in primary ESCA, and divided the ESCA patients into high- and low-risk groups based on overall survival (OS). The Kaplan-Meier curves showed the high predictive ability of the prognostic signature in the training, testing, and full data sets (P=2.407e-03, P=1.044e-02, and P=2.535e-04, respectively). Multivariate Cox regression analyses were performed with age, grade, tumor stage, tumor type and the risk score as covariables. The risk score supports the use of a prognostic signature as an independent prognostic factor [training data set: hazard ratio (HR) =1.185, 95% confidence interval (95% CI): 1.013–1.388, P=0.034; testing data set: HR =2.056, 95% CI: 1.015–4.166, P=0.045; full data set: HR =1.197, 95% CI: 1.059–1.354, P=0.004]. The area under the curve (AUC) of the receiver operating characteristic curve validated the high predictive accuracy of the IRG signature in the training, testing, and full data set (AUCs =0.808, 0.657, and 0.751, respectively). The infiltration level of the activated mast cells was significantly higher in the high-risk group than the low-risk group; thus, infiltrating mast cells are associated with worse OS in ESCA patients.ConclusionsOur IRG prognostic signature provides a new direction to predict the survival of primary ESCA patients and has the potential ability to establish, promote, and improve personalized treatment procedures based on each patient’s risk.  相似文献   
157.
Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tickborne bandavirus mainly transmitted by Haemaphysalis longicornis ticks in East Asia, mostly in rural areas. As of April 2022, the amplifying host involved in the natural transmission of SFTSV remained unidentified. Our epidemiologic field survey conducted in endemic areas in China showed that hedgehogs were widely distributed, had heavy tick infestations, and had high SFTSV seroprevalence and RNA prevalence. After experimental infection of Erinaceus amurensis and Atelerix albiventris hedgehogs with SFTSV, we detected robust but transitory viremias that lasted for 9–11 days. We completed the SFTSV transmission cycle between hedgehogs and nymph and adult H. longicornis ticks under laboratory conditions with 100% efficiency. Furthermore, naive H. longicornis ticks could be infected by SFTSV-positive ticks co-feeding on naive hedgehogs; we confirmed transstadial transmission of SFTSV. Our study suggests that the hedgehogs are a notable wildlife amplifying host of SFTSV in China.  相似文献   
158.
Background: Nutritional status affects the health of the public and is one of the key factors influencing social-economic development. To date, little research on the nutritional status of the Macao university student population has been conducted. Objectives: To identify and evaluate the dietary pattern and the nutritional intake among Macao university students. Methods: The Macao students were selected by the stratified cluster random sampling method. A semi-quantitative food frequency questionnaire was used to investigate food consumption. Data were analyzed through a t-test and factor analysis by using SPSS Version 24.0. Results: A total of 1230 questionnaires were distributed. From the respondents, 1067 (86.7%) were valid. In general, we identified three major dietary patterns in this population: (1) fruit and vegetable dietary pattern, characterized by abundant consumption of fruits and vegetables; (2) grain and high fat dietary pattern, characterized as high intakes of grains and animal foods; (3) high sugar dietary pattern, characterized by a large quantity of daily sugary drinks. The average daily intake of vitamin A, thiamine, calcium, and iodine were significantly lower than the Chinese Recommended Nutrient Intake (RNI) in the subjects. Conclusions: The dietary pattern of Macao students is similar to that of other Asians. Surprisingly, the daily intake of vitamin A, thiamine, calcium, and iodine by Macao university students is significantly lower than the Chinese RNI.  相似文献   
159.
Background: The nutritional risk index (NRI) is an independent prognostic factor for overall survival in various cancers, but its prognostic value in breast cancer remains unclear. This study aimed to explore the relationship between the NRI and overall survival (OS) in breast cancer and to develop a predictive nomogram. Methods: We retrospectively enrolled 1347 breast cancer patients who underwent mastectomy or lumpectomy between January 2011 and November 2012. Using a cutoff value of 110.59, patients were divided into a high-NRI group and a low-NRI group. OS was compared between the two groups. Clinicopathological factors independently associated with survival were used to construct a predictive nomogram. Results: Of the 1347 patients, 534 patients were classified as high NRI and 813 as low NRI. OS was significantly shorter in low-NRI patients. The 3- and 5-year OS rates were 87.3% and 73.4%, respectively, in the high-NRI group whereas they were 83.0% and 67.2%, respectively, in the low-NRI group. Cox regression analysis found that histopathological type, tumor size, lymph node status, progesterone receptor (PR) status, Ki-67, and NRI were independently associated with OS. Conclusions: NRI is an independent prognostic factor of OS in breast cancer patients. The proposed nomogram model may be a useful tool for individualized survival prediction.  相似文献   
160.
Background: Mental illness places as a distant first in global burdens, exceeding both cardiovascular and circulatory diseases, in terms of the years lived with the disability. The emergence of the new and burgeoning area of “Nutrition Psychiatry” offers promise in improving mental health with diet. Mental health and well-being are critical to commuters but rarely recieve the attention they need. This study aimed to examine the bidirectional relationship between the frequency of eating out and depression, anxiety, and stress symptoms in a sample of Beijing commuters. Methods: A total of 3337 commuters (mean (SD) age, 38.78 (10.41); 74.74% males) from the cohort study CHCN-BTH were included. The psychiatric symptoms were evaluated using a 21-item self-reported depression–anxiety–stress scale (DASS-21). A Cochran–Armitage trend chi-square test, restricted cubic spline, multiple logistic regression, multinomial logit models, and E-values were performed to estimate the associations between eating out and psychiatric symptoms in both directions. Results: A daily rate of eating out more than 50% had a higher risk for depression (OR, 95% CI: 1.68, 1.184–2.393), anxiety (1.73, 1.259–2.369), and stress (1.99, 1.191–3.329) than the individuals eating at home. A higher frequency of eating out for lunch was significantly associated with an increased risk of depression (1.78, 1.28–2.46), anxiety (1.67, 1.26–2.23), and stress (2.05, 1.31–3.22). Similar results were found when eating out for dinner with increased risks for depression 2.20 (1.59, 3.06), anxiety 1.91 (1.42, 2.59), and stress 2.61 (1.68, 4.05). There is limited evidence supporting the effects of psychiatric symptoms on the frequency of eating out in the reverse analyses. Conclusions: The frequency of eating out is positively associated with an increased risk of psychiatric symptoms, especially when eating out for lunch and dinner. People eating at home have the lowest risk of suffering psychiatric symptoms, followed by those eating in the workplace canteen. Eating at home should be considered for future recommendations for the prevention of psychiatric symptoms.  相似文献   
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