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71.
目的探讨在海拔3 700 m和5 200 m高原口服富氧水对肺功能的影响。方法(1)在海拔3 700 m将20名已习服半年的男性志愿者分为实验组和对照组,实验组口服5%葡萄糖注射液制成的富氧水,对照组口服5%葡萄糖注射液,均每次500 m l,2次/d。饮用3 d后检测其肺功能,检测指标包括FVC、FEV1、FEV1%、MMEF、PEF和MVV。(2)对首次进驻海拔5 200 m的36名男性志愿者,自海拔1 400 m驻地乘汽车2 d到达海拔3 700 m当日随机分实验组和对照组,同前服用富氧水或生理盐水,直至进入海拔5 200 m某哨卡第6天,共服9d后检测肺功能。结果习服志愿者口服富氧水3 d和初进高原志愿者口服富氧水9 d,肺功能指标中FVC、FEV、MMEF、PEF、MVV均显著增高(P〈0.01,或P〈0.05),FEV1%无显著性变化(P〉0.05)。结论在高原口服富氧水能提高移居者的肺通气功能。  相似文献   
72.

Background

Atrophy of the pancreatic parenchyma, which occurs frequently after pylorus-preserving pancreaticoduodenectomy (PPPD), is often associated with pancreatic exocrine insufficiency. Many surgeons prefer to insert a drainage tube into the remnant pancreatic duct primarily to prevent pancreatic leakage at the pancreaticojejunostomy (PJ) after PPPD. Drainage methods vary widely but can be roughly classified as internal or external drainage. This study intended to evaluate their effects on pancreatic parenchymal atrophy following PPPD.

Methods

Fifty-seven patients who underwent PPPD were retrospectively divided into two groups, 28 who underwent external and 29 who underwent internal pancreatic drainage. External drainage tubes were removed 4 weeks after PPPD. The volume of the pancreatic parenchyma was serially measured on abdominal computed tomography (CT) scans before PPPD, as well as 7 days and 3, 6, and 12 months after surgery. Degree of pancreatic parenchymal atrophy was determined by calculating pancreatic volume relative to that on day 7.

Results

Univariate analysis showed that patient sex, age, body mass index, concurrent pancreatitis, pathology, and types of PJ did not significantly affect changes in pancreatic volume following PPPD. The degree of pancreatic volume atrophy did not differ significantly in the external and internal drainage groups. No patient in the external drainage group experienced drainage-related surgical complications. The incidence of PJ leak was comparable in the two groups. Postoperative pancreatic atrophy did not induce new-onset diabetes mellitus at 1 year.

Conclusions

Both external and internal pancreatic drainage methods showed similar atrophy rate of the pancreatic parenchyma following PPPD.  相似文献   
73.
Background/AimsThe worldwide coronavirus disease 2019 pandemic has led endoscopists to use personal protective equipment (PPE) for infection prevention. This study aimed to investigate whether wearing a face shield as PPE affects the quality of colonoscopy.MethodsWe reviewed the medical records and colonoscopy findings of patients who underwent colonoscopies at Asan Medical Center, Korea from March 10 to May 31, 2020. The colonoscopies in this study were performed by five gastroenterology fellows and four expert endoscopists. We compared colonoscopy quality indicators, such as withdrawal time, adenoma detection rate (ADR), mean number of adenomas per colonoscopy (APC), polypectomy time, and polypectomy adverse events, both before and after face shields were added as PPE on April 13, 2020.ResultsOf the 1,344 colonoscopies analyzed, 715 and 629 were performed before and after the introduction of face shields, respectively. The median withdrawal time was similar between the face shield and no-face shield groups (8.72 minutes vs 8.68 minutes, p=0.816), as was the ADR (41.5% vs 39.8%, p=0.605) and APC (0.72 vs 0.77, p=0.510). Polypectomy-associated quality indicators, such as polypectomy time and polypectomy adverse events were also not different between the groups. Quality indicators were not different between the face shield and no-face shield groups of gastroenterology fellows, or of expert endoscopists.ConclusionsColonoscopy performance was not unfavorably affected by the use of a face shield. PPE, including face shields, can be recommended without a concern about colonoscopy quality deterioration.  相似文献   
74.
Histone deacetylase (HDAC) inhibitors are currently being tested as anticancer agents in clinical trials. Chromatin remodeling, such as through histone acetylation, is a fundamental phenomenon in eukaryotic cell biology, bearing implications to numerous physiological and pathological phenomena. Here, we discuss recent data from our own laboratory and those of others demonstrating antifibrotic and renoprotective effect of HDAC inhibitors in diabetic kidneys, and the possible mechanisms including the role of reactive oxygen species. HDAC inhibitors may prove to be a novel class of multitarget agents in the treatment of diabetic nephropathy.  相似文献   
75.
During the course of evolution, animals encountered the harmful effects of fungi, which are strong pathogens. Therefore, they have developed powerful mechanisms to protect themselves against these fungal invaders. β-Glucans are glucose polymers of a linear β(1,3)-glucan backbone with β(1,6)-linked side chains. The immunostimulatory and antitumor activities of β-glucans have been reported; however, their mechanisms have only begun to be elucidated. Fungal and particulate β-glucans, despite their large size, can be taken up by the M cells of Peyer''s patches, and interact with macrophages or dendritic cells (DCs) and activate systemic immune responses to overcome the fungal infection. The sampled β-glucans function as pathogen-associated molecular patterns (PAMPs) and are recognized by pattern recognition receptors (PRRs) on innate immune cells. Dectin-1 receptor systems have been incorporated as the PRRs of β-glucans in the innate immune cells of higher animal systems, which function on the front line against fungal infection, and have been exploited in cancer treatments to enhance systemic immune function. Dectin-1 on macrophages and DCs performs dual functions: internalization of β-glucan-containing particles and transmittance of its signals into the nucleus. This review will depict in detail how the physicochemical nature of β-glucan contributes to its immunostimulating effect in hosts and the potential uses of β-glucan by elucidating the dectin-1 signal transduction pathway. The elucidation of β-glucan and its signaling pathway will undoubtedly open a new research area on its potential therapeutic applications, including as immunostimulants for antifungal and anti-cancer regimens.  相似文献   
76.
目的:观察艾灸对Apo E~(-/-)小鼠主动脉内肿瘤坏死因子(TNF-α)、白细胞介素-10(IL-10)及基质金属蛋白酶9(MMP-9)的影响,并从抑制炎性反应,稳定动脉粥样硬化斑块等角度探讨艾灸在防治动脉粥样硬化中的机制。方法:将48只采用高脂饮食喂养的载脂蛋白E基因敲除小鼠(Apo E~(-/-)小鼠)作为动脉粥样硬化模型,并随机分为3组:艾灸组,模型组,药物对照组。并将16只同龄相同遗传背景的C57BL/6小鼠作为空白对照组。空白组、模型组小鼠每天常规抓取、固定,并放置假艾灸装置。艾灸组小鼠每天抓取固定,并艾灸膻中穴。药物组小鼠每天采用辛伐他汀0.28 mg/100 g灌胃,所有干预20 min/d,6 d/周,干预14周后牺牲,取材检测。Elisa法测定主动脉内TNF-α、IL-10、MMP-9的含量。油红O染色观察胸主动脉病理改变。结果:1)与模型组相比,艾灸组,药物组小鼠主动脉内TNF-α、MMP-9含量明显降低(P0.05),艾灸组,药物组之间无明显差异;与模型组相比,药物组IL-10水平明显升高有统计学意义(P0.05),艾灸组小鼠主动脉内IL-10呈升高趋势,但无统计学意义。2)胸主动脉病理改变:与空白组相比,模型组胸主动脉可见明显的AS斑块,内膜破坏,中膜增厚,平滑肌细胞破坏变性,管腔变狭窄。相比于模型组,艾灸组及药物组主动脉病变明显减轻。结论:1)艾灸可以有效缓解动脉粥样硬化病变,抑制动脉粥样硬化斑块生长;2)艾灸可以抑制体内炎性反应,并具有稳定斑块的作用  相似文献   
77.
We investigated the effects of resveratrol on metastasis in in vitro and in vivo systems. 4T1 cells were cultured in the presence of various concentrations (0-30 µmol/L) of resveratrol. For experimental metastasis, BALB/c mice were injected intravenously with 4T1 cells in the tail vein, and were orally administered various concentrations (0, 100, or 200 mg/kg Body weight) of resveratrol for 21 days. After resveratrol treatment, cell adhesion, wound migration, invasion, and MMP-9 activity were significantly decreased in a dose-dependent manner in 4T1 cells (P < 0.05). The numbers of pulmonary nodules were significantly decreased in mice fed the resveratrol (P < 0.05). The plasma MMP-9 activity was decreased in response to treatment with resveratrol in mice (P < 0.05). We conclude that resveratrol inhibits cancer metastasis both in vitro and in vivo, and this inhibition is likely due to the decrease in MMP-9 activity caused by resveratrol.  相似文献   
78.
Diabetes is a chronic disease that is characterized by an increased blood glucose level due to insulin resistance. Type 2 diabetes is common in middle aged and old people. In this work, we present a technique to analyze dynamic foot pressures images and classify them into normal, diabetes type 2 with and without neuropathy classes. Plantar pressure images were obtained using the F-Scan (Tekscan, USA) in-shoe measurement system. We used Principal Component Analysis (PCA) and extracted the eigenvalues from different regions of the foot image. The features extracted from region 1 of the foot pressure image, which were found to be clinically significant, were fed into the Fuzzy classifier (Sugeno model) for automatic classification. Our results show that the proposed method is able to identify the unknown class with an accuracy of 93.7%, sensitivity of 100%, and specificity of 83.3%. Moreover, in this work, we have proposed an integrated index using the eigenvalues to differentiate the normal subjects from diabetes with and without neuropathy subjects using just one number. This index will help the clinicians in easy and objective daily screening, and it can also be used as an adjunct tool to cross check their diagnosis.  相似文献   
79.
We describe Guatemalan birth attendants’ identification of vulnerable newborns, their evaluation of gestational age and anthropometry, and the validity of the Capurro and New Ballard newborn gestational age assessment methods. We interviewed 49 birth attendants and trained 10 of these women to assess 63 newborns. The Capurro and Ballard methods were correlated (Spearman rho = .75, p < .001) and showed agreement (Bland-Altman plot, difference and bias, ?0.33 ± 1.3 weeks). Prematurity was estimated at 27% (Ballard) and 24% (Capurro); low birth weight (LBW) was 30%. Capurro provided a simplified, equivalent estimate of gestational age compared with New Ballard that could be used by birth attendants.  相似文献   
80.
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