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991.
目的:研究穿山龙总皂苷对抑制慢性迁延期哮喘小鼠气道壁及支气管平滑肌增生,抑制肺泡灌洗液、肺组织匀浆中白介素-17A的表达的影响。方法:清洁级BALB/c小鼠70只随机分为空白对照组、模型对照组、穿山龙总皂苷高剂量组、中剂量组、低剂量组、阳性对照组(醋酸泼尼松组)、穿山龙总皂苷+醋酸泼尼松组。卵蛋白(OVA)致敏激发小鼠制作哮喘小鼠模型,在实验第18~55天,空白对照组、模型对照组以生理盐水灌胃,治疗组穿山龙总皂苷高、中、低剂量组分别每天灌胃给予穿山龙总皂苷80、40、20 mg/kg,阳性对照组给醋酸泼尼松混悬液10 mg/kg,穿山龙总皂苷+醋酸泼尼松组给穿山龙总皂苷40 mg/kg和醋酸泼尼松5 mg/kg。实验结束后HE染色观察哮喘小鼠肺组织病理形态变化,测定气道平滑肌面积和气道内壁面积,ELISA法测定肺泡灌洗液和肺组织匀浆中白介素-17A水平。结果:穿山龙总皂苷能抑制慢性迁延期哮喘小鼠气道壁及支气管平滑肌的增生,抑制其肺泡灌洗液和肺匀浆中白介素-17A表达的水平。与空白对照组比较,模型对照组小鼠气道平滑肌、气道内壁增厚(P0.01),肺泡灌洗液和肺组织匀浆中IL-17A明显升高(P0.01);与模型对照组比较,气道平滑肌、气道内壁增厚缓解(P0.01),低、高、中剂量组IL-17A水平降低(P0.01);穿山龙治疗组间比较,中、高剂量组比低剂量组对气道平滑肌、气道内壁增厚改善效果明显(P均0.05),中剂量组对小鼠IL-17A表达的影响更为显著(P0.01);与阳性对照组比较,穿山龙总皂苷+醋酸泼尼松组对小鼠IL-17A表达影响更为显著(P0.01)。结论:穿山龙总皂苷能够抑制慢性迁延期哮喘小鼠气道壁及支气管平滑肌的增生,抑制其肺泡灌洗液、肺组织匀浆中白介素-17A的表达,控制哮喘的发生、发展。  相似文献   
992.
Background/AimsInflammatory bowel disease (IBD) is associated with the occurrence of venous thromboembolism (VTE). However, to date, there have been few studies on the risk of VTE in Asian IBD patients. We aimed to estimate the incidence of VTE in Asian IBD patients and to determine if IBD is related to increased VTE risk.MethodsWe performed a population-based cohort study between 2004 and 2015 using Korean National Health Insurance data. IBD and VTE were defined by ICD-10 codes. Incidence rates of VTE were calculated among patients with IBD and among age- and sex-matched controls. Hazard ratios were estimated using Cox regression with adjustment for multiple variables. We performed additional analyses stratifying by age, sex, Charlson comorbidity index (CCI) score, and disease type.ResultsAmong the 45,037 patients with IBD (IBD cohort) and 133,019 matched controls (non-IBD cohort) included in our analysis, 411 IBD patients and 641 controls developed VTE. The IBD cohort had a higher incidence rate ratio and risk of VTE than the non-IBD cohort (incidence rate ratio 1.92 and hazard ratio 1.93). Older age, female sex, higher CCI scores, cardiovascular disease, chronic kidney disease, use of steroids, and hospitalization were significant risk factors for VTE in patients with IBD.ConclusionsThe IBD patients in this study were approximately two times more likely to develop VTE than the non-IBD individuals. Our findings support the need for thromboprophylaxis in Asian IBD patients with various factors that further increase the risk of VTE.  相似文献   
993.
BackgroundWe investigated the association between individual components of metabolic syndrome (MetS) and left ventricular (LV) geometric changes, including diastolic dysfunction, in a large cohort of healthy individuals.MethodsOverall, 148 461 adults who underwent echocardiography during a health‐screening program were enrolled. Geographic characteristics on echocardiography and several markers of LV relaxation function were identified according to individual MetS components. Univariate linear regression analysis and a multivariate regression model adjusted for factors known to influence LV relaxation function were conducted.ResultsThe prevalence of LV diastolic dysfunction (LVDD) was higher in the MetS group than in the non‐MetS group (0.56% vs. 0.27%, p < .001). In univariate and multivariate analyses, E/A ratio, e′ velocity, and left atrial volume index were significantly associated with each component of MetS and covariates (all p ≤ .001). In the age‐ and sex‐adjusted model, MetS was significantly associated with LVDD (odds ratio [95% confidence interval], 1.350 [1.103, 1.652]). However, subjects with more MetS components did not have a significantly higher risk of LVDD. As the analysis was stratified by sex, the multivariate regression model showed that MetS was significantly associated with LVDD only in men (1.3 [1.00, 1.68]) with higher risk in more MetS component (p for trend < .001). In particular, triglyceride (TG) and waist circumference (WC) among MetS components were significantly associated with LVDD in men.ConclusionsMetS was associated with the risk of LVDD, especially in men, with a dose‐dependent association between an increasing number of components of MetS and LVDD. TG and WC were independent risk factors for LVDD in men.  相似文献   
994.
Iodinated contrast media (ICM) have become one of the major causes of drug hypersensitivity reactions (HSRs) related to increasing numbers of ICM-based radiological imaging procedures. Strategies for diagnosing and preventing ICM-induced HSRs have not been uniformly standardized yet. However, advances have been made based on the results of recent research. A previous history of hypersensitivity to ICM is the most significant risk factor for developing HSR by ICM. Avoidance of culprit agents and premedication is the main strategy to prevent recurrences of HSRs in high-risk patients. In addition, we strongly recommend identifying sensitized ICM using skin tests to determine immunoglobulin E-mediated or delayed-type allergy and to guide the choice of an alternative contrast agent. ICM provocation test procedures have been established and are helpful in selected cases. In this paper, we review how to evaluate patients who have experienced immediate or delayed HSRs caused by ICM to minimize the risk of recurrence and discuss unmet needs that require further research.  相似文献   
995.
The high-dose glucocorticosteroid (GC) treatment is the first choice for dermatomyositis complicated with interstitial lung disease (DM-ILD) but patients are resistant to the high-dose GC monotherapy. Besides, the high dose of GC, the secondary immunosuppressive agent(s) is necessary but there is controversy for the selection of immunosuppressive agent(s). The objectives of the study were to analyze the efficacy of different therapeutic options for DM-ILD to identify the optimal therapy. A total of 60 patients had received intravenous 1.0–2.0 mg/ kg/day prednisolone for DM-ILD. In severe conditions, patients had received oral 1 to 3 mg/day tacrolimus (TAC), 500 mg/ m2/month cyclophosphamide (CY), and/or 1 g/ day methylprednisolone pulse (TI cohort, n = 24). In severe conditions, patients had received 1 g/day methylprednisolone pulse and 2–3 mg/ kg/day cyclosporine A (CsA) and/or 500 mg/ m2/month CY (existing historical treatment; CT cohort, n = 36). Patients of the TI cohort did not receive CsA. Patients in the CT cohort were received CY in significantly fewer numbers than those of the TI cohort during treatment (P = .0112). A total of 11 (46%) patients from the TI cohort and 14 (39%) patients from the CT cohort were developed relapsed. At the end of the 30-months, higher numbers of patients of the TI cohort had an event(s) free survival than those of the CT cohort (7 (29%) vs 2 (6%), P = .0229). Also, higher numbers of patients of the TI cohort had survived irrespective of an event(s) than those of the CT cohort (21 (87%) vs 22 (61%), P = .0399). Patients of the TI cohort had developed herpes zoster (2 (8%)) and cytomegalovirus (4 (17%)) infections. Patients of the CT cohort developed renal dysfunction (10 (28%)). Hyperglycemia, hyperlipidemia, and fracture (GC-related toxicities) were also reported in both cohorts and these toxicities were fever in the TI cohort. The addition of TAC to high doses GC with CY is an ideal treatment for severe conditions of DM-ILD (Level of Evidence: III; Technical Efficacy Stage: 4).  相似文献   
996.
997.
998.
目的:探讨肠间质细胞(ICC)、神经生长因子受体(NGFR)及一氧化氮合酶(NOS)与先天性巨结肠(HD)发病的关系.方法:应用c-kit及NGFR免疫组化法和NADPH黄递酶组化法观察10例HD患者病变结肠及8例对照组结肠ICC,NGFR及NOS的分布.结果:ICC密布于对照组结肠环肌浅表层及肌间神经丛周围并相互交织成网状结构,肠壁内含丰富的NGFR及NOS阳性神经节细胞和神经纤维.HD病变肠壁内ICC数量减少、网状结构破坏,缺乏NGFR及NOS阳性神经节细胞和神经纤维.结论:ICC,NGFR及NOS的异常分布可能与HD无神经节细胞结肠的舒张功能障碍有关.  相似文献   
999.
BackgroundThe rapid urease test (RUT) is a major diagnostic tool for detecting Helicobacter pylori infection. This study aimed to establish an objective method for measuring the color changes in the RUT kit to improve the test’s diagnostic accuracy.MethodsA UV-visible spectrophotometer was selected as the colorimeter; experiments were conducted in three stages to objectively identify the color changes in the RUT kit.ResultsFirst, the urea broth solution showed an identifiable color change from yellow to red as the pH increased by 0.2. The largest transmittance difference detected using the UV-visible spectrophotometer was observed at a 590-nm wavelength. Second, the commercialized RUT kit also showed a gradual color change according to the pH change detected using the UV-visible spectrophotometer. Third, 13 cases of negative RUT results with a biopsy specimen and 16 of positive RUT results were collected. The transmittance detected using the UV-visible spectrophotometer showed a clear division between the positive and negative RUT groups; the largest difference was observed at a 559-nm wavelength. The lowest transmittance in the negative RUT group was 64, while the highest in the positive RUT group was 56, at the 559-nm wavelength. The UV-visible spectrophotometry reading showed a consistency of 92.7% compared with that of manual reading.ConclusionA transmittance of 60 at a 559-nm wavelength detected using UV-visible spectrophotometer can be used as a cutoff value for interpreting RUT results; this will help develop an automatic RUT kit reader with a high accuracy.  相似文献   
1000.
Despite the low prevalence of secondary bacterial infection in coronavirus disease 2019 (COVID-19) patients, most of them were administered antibiotic therapy empirically. However, the prognostic impact of empirical antibiotic therapy has not been evaluated. We conducted retrospective propensity score-matched case-control study of 233 COVID-19 patients with moderate to severe illnesses who required oxygen therapy and evaluated whether empirical antibiotic therapy could improve clinical outcomes. Empirical antibiotic therapy did not improve clinical outcomes including length of stay, days with oxygen requirement, the proportion of patients with increased oxygen demand, the proportion of patients who required mechanical ventilation, and overall mortality. This finding implies that routine administration of antibiotics for the treatment of COVID-19 is not essential and should be restricted.  相似文献   
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