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71.
Two sand culture experiments were carried out to identify commercial cultivars of lucerne or alfalfa (Medicago sativa L.) which contain elite, Mn-tolerant plants for use in a selection programme to increase the acid-soil tolerance of this perennial legume. Differences in Mn tolerance, both within and between cultivars, were observed when a range of cultivars were exposed to regular waterings with dilute nutrient solution containing 20 or 25 mg Mn L–1. Under these moderately toxic regimes, the winter dormant cultivars Cimmaron and WL 318 were found to contain elite plants that had greater dry matter yields than their mean cultivar yield under non-toxic Mn conditions.Cultivars which contained elite, Mn-tolerant plants could not be identified by phenotypic characteristics such as their height or their toxicity symptom score, nor by their winter dormancy class. Possible reasons for the occurrence of elite plants in these cultivars are discussed. The elite, high yielding Mn-tolerant plants could not be identified from the other plants within their cultivar population by their Mn toxicity symptoms nor by their height.  相似文献   
72.
A comparative study into the pathogenicity of four Helminthosporiumspp. towards rice cultivars in Marocco In this paper, the behaviour of four Helminthosporium species on nine rice cultivars widely cultivated in Morocco, permit the classification of this species according to their virulence. Helminthosporium oryzae and Helminthosporium sativum are the most virulent and the best equipped to sporule on all varieties of tested lesions. The level of pathogenicity of Helminthosporium spiciferum and Helminthosporium australiensis and their capacity to sporule on host plant depend on the rice variety used. At the same time, each Helminthosporium induces characteristics symptoms on rice leaves.  相似文献   
73.
《Cancer epidemiology》2014,38(6):757-764
BackgroundA cancer diagnosis and subsequent treatments constitute a significantly increased psychological burden among cancer patients. This study examined the prevalence of current depression and the risk factors associated with a high burden of depression among cancer survivors in the US.MethodsWe analyzed data from 3550 cancer survivors (aged ≥18 years) and 26,917 adults without cancer who participated in the 2010 Behavioral Risk Factor Surveillance System. Depressive symptoms were assessed by the Patient Health Questionnaire-8 diagnostic algorithm. Participants with a total depression severity score of ≥10 were defined as having current depression. Prevalence and prevalence ratios were estimated by conducting log-linear regression analysis while controlling for potential confounders.ResultsOverall, 13.7% of cancer survivors (vs. 8.9% of adults without cancer, P < 0.001) reported having current depression; the prevalence varied significantly by cancer category. Among cancer survivors, after multivariate adjustment for covariates, cancer diagnosis within a year, being in ‘other’ racial/ethnic group, divorced, separated, widowed, or never married, current or former smoker, or having histories of diabetes, disability, or depression were associated with significantly higher prevalence ratios for current depression; whereas being at an advanced age (≥60 years old), attaining educational levels of >high school graduate, or engaging in leisure-time physical activity were associated with significantly lower prevalence ratios for current depression.ConclusionOur results indicate that cancer survivors are at increased risk of current depression. Targeting cancer survivors at high risk of depressive issues may be especially important for clinical support and interventions aimed at improving mental well-being.  相似文献   
74.

Introduction

Bone marrow lesion (BML) size may be an important imaging biomarker for osteoarthritis-related clinical trials and reducing BML size may be an important therapeutic goal. However, data on the interrelationships between BML size, pain, and structural progression are inconsistent and rarely examined in the same cohort. Therefore, we evaluated the cross-sectional and longitudinal associations of BML volume with knee pain and joint space narrowing (JSN).

Methods

A BML volume assessment was performed on magnetic resonance images of the knee collected at the 24- and 48-month Osteoarthritis Initiative visits from a convenience sample of 404 participants in the progression cohort. During the same visits, knee pain was assessed with WOMAC pain scores and knee radiographs were acquired and scored for JSN. BML volume was summed to generate a total knee volume and an index tibiofemoral compartment volume (compartment with greater baseline JSN). Primary analyses included multiple linear regressions (outcome = pain, predictor = total knee BML volume) and logistic regressions (outcome = JSN, predictor = index tibiofemoral compartment BML volume).

Results

This sample was 49% female with a mean age of 63 (9.2 standard deviation (SD)) years, and 71% had radiographic osteoarthritis in the study knee. Larger baseline BMLs were associated with greater baseline knee pain (P = 0.01), the presence of JSN at baseline (odds ratio (OR) = 1.50, 95% confidence interval (CI) = 1.23 to 1.83), and JSN progression (OR = 1.27, 95%CI = 1.11 to 1.46). Changes in total knee BML volume had a positive association with changes in knee pain severity (P = 0.004) and this association may be driven by knees that were progressing from no or small baseline BMLs to larger BMLs. In contrast, we found no linear positive relationship between BML volume change and JSN progression. Instead, regression of medial tibiofemoral BML volume was associated with JSN progression compared to knees with no or minimal changes in BML volume (OR = 3.36, 95%CI = 1.55 to 7.28). However, follow-up analyses indicated that the association between JSN progression and BML volume change may primarily be influenced by baseline BML volume.

Conclusion

Large baseline BMLs are associated with greater baseline knee pain, the presence of JSN at baseline, and disease progression. Additionally, BML regression is associated with decreased knee pain but not a reduced risk of concurrent JSN progression.  相似文献   
75.
We analyzed relationships of hepatic and pancreatic biomarkers with the cholestatic syndrome and tumor stage in exocrine pancreatic cancer (N = 183). Information on laboratory tests and on signs and symptoms was obtained from medical records and patient interviews. Bilirubin, aspartate aminotransferase (AST), γ-glutamyltransferase (GGT) and alkaline phosphatase were lower in tumor stage IV. The association was due to the relationship between cholestatic syndrome and earlier presentation of patients. There was no association between hepatic biomarkers and stage when adjusting by cholestatic syndrome. Relationships of hepatic and pancreatic biomarkers with pancreatic symptoms and tumor stage must be controlled in “-omics” and other studies using biomarkers.  相似文献   
76.

Background

Levels of Interleukin-6 (IL-6) and C-creative protein (CRP) indicating systemic inflammation are known to be elevated in chronic diseases including chronic obstructive pulmonary disease (COPD) and depression. Comorbid depression is common in patients with COPD, but no studies have investigated whether proinflammatory cytokines mediate the association between pulmonary function and depressive symptoms in healthy individuals with no known history of obstructive pulmonary diseases.

Methods

In a population-based sample (n = 2077) of individuals aged 55 and above with no known history of obstructive pulmonary disease in the Singapore Longitudinal Ageing Study (SLAS), we analyzed the relationships between IL-6 and CRP, depressive symptoms (GDS-15 ≥5) and obstructive pulmonary function (FEV1% predicted and FEV1/FVC% predicted).

Results

High serum levels of IL-6 and CRP were associated with greater prevalence of depressive symptoms (p < 0.05). High IL-6, high CRP and depressive symptoms were independently associated with decreased FEV1% predicted and FEV1/FVC% predicted after adjusting for smoking status, BMI and number of chronic inflammatory diseases. Increasing grades of combination of inflammatory markers and/or depressive symptoms was associated with progressive increases in pulmonary obstruction. In hierarchical models, the significant association of depressive symptoms with pulmonary obstruction was reduced by the presence of IL-6 and CRP.

Conclusions

This study found for the first time an association of depressive symptoms and pulmonary function in older adults which appeared to be partly mediated by proinflammatory cytokines. Further studies should be conducted to investigate proinflammatory immune markers and depressive symptoms as potential phenotypic indicators for chronic obstructive airway disorders in older adults.  相似文献   
77.

Background

Increased airway wall thickness (AWT) and parenchymal lung destruction both contribute to airflow limitation. Advances in computed tomography (CT) post-processing imaging allow to quantify these features. The aim of this Dutch population study is to assess the relationships between AWT, lung function, emphysema and respiratory symptoms.

Methods

AWT and emphysema were assessed by low-dose CT in 500 male heavy smokers, randomly selected from a lung cancer screening population. AWT was measured in each lung lobe in cross-sectionally reformatted images with an automated imaging program at locations with an internal diameter of 3.5 mm, and validated in smaller cohorts of patients. The 15th percentile method (Perc15) was used to assess the severity of emphysema. Information about respiratory symptoms and smoking behavior was collected by questionnaires and lung function by spirometry.

Results

Median AWT in airways with an internal diameter of 3.5 mm (AWT3.5) was 0.57 (0.44 - 0.74) mm. Median AWT in subjects without symptoms was 0.52 (0.41-0.66) and in those with dyspnea and/or wheezing 0.65 (0.52-0.81) mm (p<0.001). In the multivariate analysis only AWT3.5 and emphysema independently explained 31.1%and 9.5%of the variance in FEV1%predicted, respectively, after adjustment for smoking behavior.

Conclusions

Post processing standardization of airway wall measurements provides a reliable and useful method to assess airway wall thickness. Increased airway wall thickness contributes more to airflow limitation than emphysema in a smoking male population even after adjustment for smoking behavior.  相似文献   
78.
Chronic obstructive pulmonary disease (COPD) symptoms in the morning, including dyspnea and sputum production, affect patients’ quality of life and limit their ability to carry out even simple morning activities. It is now emerging that these symptoms are associated with increased risk of exacerbations and work absenteeism, suggesting that they have a more profound impact on patients than previously thought. The development of validated patient-reported outcome (PRO) questionnaires to capture patients’ experience of COPD symptoms in the morning is, therefore, vital for establishing effective and comprehensive management strategies. Although it is well established that long-acting bronchodilators are effective in improving COPD symptoms, the limited available data on their impact on morning symptoms and activities have been obtained with non-validated PRO questionnaires. In this review, we discuss the impact of COPD symptoms in the morning and available tools used to evaluate them, and highlight specific gaps that need to be addressed to develop standardized instruments able to meet regulatory requirement. We also present available evidence on the effect of pharmacological therapies on morning symptoms.  相似文献   
79.
目的:调查与分析遂宁地区良性前列腺增生术后下尿路症状(Lower Urinary Tract Symptoms,LUTS)发生的相关危险因素。方法:2014年9月到2019年10月选择在遂宁市中心医院诊治的遂宁地区良性前列腺增生症患者172例,所有患者都给予手术治疗,记录术后LUTS发生情况,调查患者的临床资料并进行影响因素分析。结果:在172例患者中,术后平均国际前列腺症状评分量表(International prostate symptom scores,IPSS)评分为5.67±0.13分,其中储尿期症状评分3.01±0.11分,排尿期症状评分为1.76±0.22分,排尿后症状评分0.89±0.14分,发生LUTS 18例(LUTS组),发生率为10.5%。LUTS组的生活质量评分高于非LUTS组(P<0.05);LUTS组的年龄、体重指数、低密度脂蛋白、总胆固醇、前列腺体积与非LUTS组对比差异有统计学意义(P<0.05);Pearson分析显示年龄、体重指数、低密度脂蛋白、总胆固醇、前列腺体积都与LUTS存在相关性(P<0.05);二元Logistic回归分析显示年龄、体重指数、低密度脂蛋白、总胆固醇、前列腺体积都为导致LUTS发生的主要因素(P<0.05)。结论:遂宁地区良性前列腺增生术后LUTS的发生比较常见,可严重影响患者的生活质量,年龄、体重指数、低密度脂蛋白、总胆固醇、前列腺体积都为导致LUTS发生的主要因素。  相似文献   
80.
目的:比较伴与不伴有边缘性人格障碍(BPD)的首发中青年抑郁症患者认知功能及临床症状的差异,并分析相关性。方法:选取自2017年3月至2020年1月于我院就诊的首发中青年抑郁症患者167例,按照纳入标椎及排除标椎,剔除21例不符合者,最终入组146例。将伴有BPD的抑郁症患者归为研究组(72例),不伴有BPD的抑郁症患者归为对照组(74例)。采用韦氏记忆量表(WMS-RC)、韦氏智能量表(WAIS-RC)、威斯康星卡片分类测验(WCST)对两组患者进行认知功能的对照性评估,采用症状自评量表(SCL-90)评估患者临床症状,Pearson相关性分析患者认知功能与临床症状的关系。结果:研究组的人际关系敏感因子评分较对照组升高(P<0.05)。研究组即刻记忆、语言智商数、操作智商数评分均低于对照组,而持续错误数多于对照组(P<0.05)。经Pearson相关性分析可得:伴有BPD的首发中青年抑郁症患者人际关系敏感因子评分与即刻记忆、语言智商数、操作智商数均呈负相关关系(P<0.05),而与持续错误数呈正相关关系(P<0.05)。结论:伴有BPD的首发中青年抑郁症患者较不伴有BPD的抑郁症患者认知功能受损更为严重,人际关系敏感性更高,且患者的认知功能与临床症状存在一定的关联。  相似文献   
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