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91.
Radiation therapy is widely used in the treatment of tumor diseases, but it can also cause serious damage to the body, so it is necessary to find effective nutritional supplements. The main purpose of this study is to evaluate the protective effect of whey hydrolysate peptides (WHPs) against 60Coγ radiation damage in mice and explore the mechanism. BALB/c mice were given WHPs by oral gavage administration for 14 days. Then, some mice underwent a 30-day survival test after 8 Gy radiation, and other mice received 3.5 Gy radiation to analyze the changes in body weight, hematology and bone marrow DNA after three and 14 days. In addition, through further analysis of the level of oxidative stress and intestinal barrier function, the possible mechanism of the radioprotective effect of WHPs was explored. The study found WHPs can prolong survival time, restore body weight, and increase the number of peripheral blood white blood cells and bone marrow DNA content in irradiated mice. In addition, WHPs can significantly improve the antioxidant capacity, inhibit pro-inflammatory cytokines and protect the intestinal barrier. These results indicate that WHPs have a certain radioprotective effect in mice, and the main mechanism is related to reducing oxidative damage.  相似文献   
92.
ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively.  相似文献   
93.
 目的 总结2例人类免疫缺陷病毒(HIV)阴性儿童马尔尼菲篮状菌病(TSM)患儿的临床特征。方法 分析某儿童医院收治的2例HIV阴性TSM患儿的临床特点及实验室资料、存在的基础疾病,并复习相关文献,总结TSM感染患儿的临床特征及诊治经验。结果 2例HIV阴性TSM患儿中病例1以右下肢肿块为首发症状,1个月余后才出现发热及咳嗽,误诊为结核感染;病例2以发热、三系减少及肝脾、淋巴结大等表现起病。病例1行基因检测为STAT1基因突变,病例2有反复灰指甲及口腔溃疡病史,均行血、骨髓培养及淋巴结活检确诊。病例1先后予以伏立康唑、两性霉素B脂质体静脉滴注,伊曲康唑口服维持治疗,共治疗1年后停药;病例2一直予以伏立康唑治疗(先静脉滴注后口服),共7个月后停药,均无复发。结论 TSM可发生在HIV阴性儿童,且可存在STAT1基因突变。对于治疗效果差的患儿,应尽早行培养或组织活检以明确诊断,并积极查找TSM可能存在的基础疾病,以到达早期诊断、早期治疗和改善预后的目的。  相似文献   
94.
We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response.  相似文献   
95.
目的:探讨子宫内膜癌在绝经前发病与绝经后发病的临床及病理特征。方法:将1990年1月—2001年1月我院收治住院有完整资料的110例病例作一回顾性分析。结果:由于绝经后组子宫内膜癌在手术分期、细胞分化、肿瘤细胞的亚型及发生淋巴结转移的程度上均差于绝经前组,提示绝经后发生子宫内膜癌的预后差于绝经前的子宫内膜癌。  相似文献   
96.
The study was designed and conducted to evaluate the plant-based diet status and its association with erectile function (EF) in Chinese young healthy men. From July 2018 to May 2020, 116 objectively proved physically and psychologically healthy men were selected. Clinical questionnaires, detailed physical examinations and blood tests were all assessed. An overall plant-based diet index (PDI) and a healthful plant-based diet index (hPDI) were developed from each participant to measure plant-based diet quantitatively. The EF was measured by both the International Index of Erectile Function-5 (IIEF-5) and the surrogated measures of endothelial function, peripheral levels of nitric oxide (NO) and E-selectin. In subjects, the mean PDI and hPDI were 53.8 ± 8.2 and 54.7 ± 8.9 respectively. Results of multivariate analysis showed that both PDI and hPDI were negatively associated with BMI (all p < .05), but had no relationships with NO, E-selectin, TT levels and IIEF-5 scores (all p > .05). In a subgroup of male population, Chinese young healthy men, the plant-based diet, measured by PDI and hPDI, was not related to erectile function. The population can adhere to plant-based diet to keep healthy without concerns of negative influence on erectile function.  相似文献   
97.
Smokers are at a higher risk of delayed union or nonunion after fracture repair. Few specific interventions are available for prevention because the molecular mechanisms that result in these negative sequelae are poorly understood. Murine models that mimic fracture healing in smokers are crucial in further understanding the local cellular and molecular alterations during fracture healing caused by smoking. We exposed three murine strains, C57BL/6J, 129X1/SvJ, and BALB/cJ, to cigarette smoke for 3 months before the induction of a midshaft transverse femoral osteotomy. We evaluated fracture healing 4 weeks after the osteotomy using radiography, micro-computed tomography (μCT), and biomechanical testing. Radiographic analysis demonstrated a significant decrease in the fracture healing capacity of smoking 129X1/SvJ mice. μCT results showed delayed remodeling of fracture calluses in all three strains after cigarette smoke exposure. Biomechanical testing indicated the most significant impairment in the functional properties of 129X1/SvJ in comparison with C57BL/6J and BALB/cJ mice after cigarette smoke exposure. Thus, the 129X1/SvJ strain is most suitable in simulating smoking-induced impaired fracture healing. Furthermore, in smoking 129X1/SvJ murine models, we investigated the molecular and cellular alterations in fracture healing caused by cigarette smoking using histology, flow cytometry, and multiplex cytokine/chemokine analysis. Histological analysis showed impaired chondrogenesis in cigarette smoking. In addition, the important reparative cell populations, including skeletal stem cells and their downstream progenitors, demonstrated decreased expansion after injury as a result of cigarette smoking. Moreover, significantly increased pro-inflammatory mediators and the recruitment of immune cells in fracture hematomas were demonstrated in smoking mice. Collectively, our findings demonstrate the significant cellular and molecular alterations during fracture healing impaired by smoking, including disrupted chondrogenesis, aberrant skeletal stem and progenitor cell activity, and a pronounced initial inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
98.
99.
Objective: To establish a high-performance liquid chromatographic method (HPLC) for the simultaneous determination of sixteen compounds from Artemisia ordosica. Methods: HPLC was used to analyze 16 quality indicators of A. ordosica. The HPLC conditions were as follows: Agilent Eclipse Plus C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (A)-water (B) as mobile phase, gradient elution: 0?10 min, 75%?65% B; 10?30 min, 65%?35 % B; and finally 30?40 min, 35%?15% B. The flow rate was 1.0 mL/min, the column temperature was 40 °C, the injection volume was 10 μL, and monitored by absorbance at 285 nm for compounds 1?10, 12 and 225 nm for compounds 11, 13?16. Results: Under the selected experimental chromatographic conditions, compounds 1?16 showed good linearity (r > 0.9993) in a wide concentration range. Their average recoveries were 99.50%, 95.38%, 97.75%, 96.00%, 98.20%, 97.50%, 95.50%, 99.33%, 96.75%, 96.50%, 98.50%, 97.83%, 99.20%, 95.33%, 97.33% and 96.30%, respectively, and the RSD were 1.99%, 1.81%, 1.63%, 1.98%, 1.67%, 1.92%, 1.74%, 1.67%, 1.90%, 1.72%, 1.88%, 1.83%, 1.79%, 1.76%, 1.81% and 1.96%, respectively. Conclusion: Based on the results of the HPLC analysis, it was concluded that p-hydroxycinnamic acid (1), O-hydroxycinnamic acid (2), coniferyl alcohol (5), 5,4''-dihydroxy-7,3''-dimethoxyflavanone (8), 5,4''-dihydroxy-7-methoxyflavanone (9), 5-hydroxy-7,4''-dimethoxyflavanone (12), dehydrofalcarindiol (13), arteordoyn A (14), dehydrofalcarinol (15) and capillarin (16) are best suited for the role of quality indicators of A. ordosica grown in different ecological environments.  相似文献   
100.
Myocardial infarction (MI) is one of the diseases with high fatality rate. Berberine (BBR) is a monomer compound with various biological functions. And some studies have confirmed that BBR plays an important role in alleviating cardiomyocyte injury after MI. However, the specific mechanism is unclear. In this study, we induced a model of MI by ligation of the left anterior descending coronary artery and we surprisingly found that BBR significantly improved ventricular remodeling, with a minor inflammatory and oxidative stress injury, and stronger angiogenesis. Moreover, BBR inhibited the secretion of Wnt5a/β-catenin pathway in macrophages after MI, thus promoting the differentiation of macrophages into M2 type. In summary, BBR effectively improved cardiac function of mice after MI, and the potential protective mechanism was associated with the regulation of inflammatory responses and the inhibition of macrophage Wnt5a/β-catenin pathway in the infarcted heart tissues. Importantly, these findings supported BBR as an effective cardioprotective drug after MI.  相似文献   
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