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91.
ObjectiveVaso-occlusive crisis (VOC) is a common clinical manifestation of sickle cell anemia (SCA) and is associated with increased proinflammatory mediators. Copeptin is the C-terminal part of the prohormone for provasopressin and seems clinically relevant in various clinical conditions. Right ventricular (RV) dysfunction significantly appears in SCA patients due to pulmonary hypertension. This study aimed to investigate the association of copeptin levels in VOC patients and evaluate RV dysfunction.Materials and MethodsA total of 108 patients were enrolled in the study. Twenty-eight SCA patients in steady state (30.2 ± 0.9 years), 25 SCA patients in VOC (36.8 ± 11.8 years), and 55 healthy individuals (31.9 ± 9.4 years) with HbAA genotype were included. Clinical, echocardiographic, and laboratory data were recorded. ELISA was used for the determination of serum levels of copeptin.ResultsVOC patients had significantly higher copeptin level compared both with controls and SCA subjects in steady state (22.6 ± 13.0 vs. 11.3 ± 5.7 pmol/L, 22.6 ± 13.0 vs. 12.4 ± 5.8 pmol/L, p = 0.009 for both). Additionally, the copeptin level was significantly higher in SCA patients with RV dysfunction than those without RV dysfunction (23.2 ± 12.2 vs. 15.3 ± 9.5 pmol/L, p = 0.024). Multiple logistic regression analysis revealed that high-sensitivity C-reactive protein and copeptin levels were found to be associated with VOC.ConclusionThis study showed that copeptin and hs-CRP levels were increased in patients with VOC, and it was found that RV dysfunction was more common in SCA patients with VOC than in the control group. Copeptin can be considered for use as a potential biomarker in predicting VOC crisis in SCA patients and in the early detection of patients with SCA who have the potential to develop RV dysfunction.  相似文献   
92.
Lee JM  Vo KD  An H  Celik A  Lee Y  Hsu CY  Lin W 《Annals of neurology》2003,53(2):227-232
The purpose of this study was to explore the feasibility of obtaining magnetic resonance-measured cerebral metabolic rate of oxygen utilization (MR-CMRO(2)) in acute ischemic stroke patients. Seven stroke patients were serially imaged: 4.5 +/- 0.9 hours (tp1), 3 to 5 days (tp2), and 1 to 3 months (tp3) after symptom onset. Diffusion-weighted, perfusion-weighted, and multiecho gradient-echo/spin-echo images were acquired; cerebral blood flow and oxygen extraction fraction maps were obtained from which CMRO(2) was calculated as the product of cerebral blood flow and oxygen extraction fraction. The final infarct lesions obtained from tp3 T2-weighted images and the "penumbra" obtained from the tp1 perfusion-weighted image-defined lesion were coregistered onto tp1 CMRO(2) maps. CMRO(2) values in the region of brain that eventually infarcted were reduced to 0.40 +/- 0.24 of the respective region on the contralateral hemisphere. The "salvaged penumbra" defined by the area of mismatch between the final infarct and the tp1 perfusion-weighted lesion demonstrated an average CMRO(2) value of 0.55 +/- 0.11 of the contralateral hemisphere. Although our results are preliminary and require further evaluation, the ability to obtain in vivo measurements of MR-CMRO(2) noninvasively potentially can provide information for determining brain tissue viability in acute ischemic stroke patients.  相似文献   
93.
目的:观察内洋地黄素水平在老龄大鼠心肌细胞缺氧复氧损伤中的变化以及地高辛抗血清的保护作用。方法:实验于2005-04/05在皖南医学院病理生理教研室完成。取10只24月龄和10只6月龄雄性普通级SD大鼠,分别制备青年和老龄大鼠心肌细胞匀浆,老龄和成年大鼠为两大组,每组分为7小组,即每只大鼠心肌随机分到各小组中,共计14小组,每组10支试管。正常对照组:给予CO2和O2的混合气体(1∶19)通气40min;缺氧复氧组:CO2,O2,N2混合气体(5∶4∶91)通气20min后换成CO2和O2的混合气体(1∶19)通气20min;阴性对照组:同缺氧复氧组,但于再给氧前加入0.1mL的非特异性灭活兔血清;地高辛抗血清组:同缺氧复氧组,但于再给氧前加入0.1mL的非特异性地高辛抗血清(分别为1∶90000,60000,30000,10000)。观察大鼠心肌细胞钠-钾-三磷酸腺苷酶活性和线粒体内钙聚集程度,分析其剂量-效应关系。结果:①缺氧复氧时,青年组和老龄组大鼠心肌分泌内洋地黄素均显著升高,但老龄组显著低于青年组[(0.081±0.03),(0.153±0.06);(0.074±0.04),(0.125±0.05)ng/g;P<0.05]。②缺氧复氧时,老龄组与青年组心肌细胞钠-钾-三磷酸腺苷酶活性显著受抑制[(0.239±0.015),(0.778±0.050);(0.350±0.047),(0.836±0.044)μkat/g;P<0.05],老龄组与青年组相比,其抑制效应显著增强(P<0.05)。③缺氧复氧时,老龄组线粒体内钙与青年组比较明显增强[(0.082±0.011),(0.495±0.095);(0.075±0.008),(0.412±0.084)mmol/L,P<0.05]。④老龄组和青年组相比,地高辛抗血清呈剂量依赖性的恢复钠-钾-三磷酸腺苷酶活性(r=0.695,0.797,n=5,P<0.05),减轻线粒体内钙聚集(r=-0.565,-0.649,n=5,P<0.05);经直线回归分析发现,老龄鼠回归系数大于青年组(酶活性抑制K=1.50,0.94,线粒体内钙K=-7.43,-6.46)。结论:心肌细胞缺氧复氧时,老龄鼠损伤较青年大鼠更显著,其机制与老龄大鼠心肌细胞钠-钾-三磷酸腺苷酶对内洋地黄素敏感性增加有关,地高辛抗血清对老龄大鼠心肌细胞缺氧复氧保护作用更有效。  相似文献   
94.
A number of linguistic and cognitive deficits have been reported during the course of Alzheimer’s disease (AD) and its preceding stage of mild cognitive impairment (MCI), with some deficits appearing years before onset of clinical symptoms. It continues to be a critical task to identify tools that may serve as an early marker of pathology that are also reliably able to distinguish AD from normal ageing. Given the limited success of classic psychometric cognitive testing, a novel approach in assessment is warranted. A potentially sensitive assessment paradigm is discourse processing. The aim of this review was to synthesize original research studies investigating comprehension of discourse in AD and MCI, and to evaluate the potential of this paradigm as a promising avenue for further research. A literature search targeting studies with AD or MCI groups over 60 years of age was conducted in PubMed, Web of Science, and PsycINFO databases. Eight articles with good quality were included in the review. Six measures of discourse comprehension—naming latency, summary, lesson, main idea, proportion of inferential clauses, true/false questions—were identified. All eight studies reported significant deficits in discourse comprehension in AD and MCI groups on five of the six measures, when compared to cognitively healthy older adults. Mixed results were observed for associations with commonly used cognitive measures. Given the consistent findings for discourse comprehension measures across all studies, we strongly recommend further research on its early predictive potential, and discuss different avenues for research.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-021-00619-5.  相似文献   
95.
Wright  DG; Kenney  RF; Oette  DH; LaRussa  VF; Boxer  LA; Malech  HL 《Blood》1994,84(4):1257-1267
Recombinant human granulocyte colony-stimulating factor (G-CSF) treatment has been shown to increase average neutrophil counts substantially in patients with childhood-onset cyclic neutropenia (or "cyclic hematopoiesis"), but not to eliminate the cyclic oscillations of neutrophil counts or those of other blood elements (monocytes, platelets, eosinophils, and reticulocytes) that are characteristic of this hematopoietic disorder. Indeed, oscillations of neutrophil counts are amplified during G-CSF treatment. We have compared the effects of recombinant granulocyte-macrophage-CSF (GM-CSF) with those of G-CSF in three patients with this disease (2 men and 1 woman, 17, 30, and 32 years of age). These patients were treated with GM-CSF (2.1 micrograms/kg/day, subcutaneously) for 6 weeks, preceded and followed by 6 to 13 weeks of detailed observation to document changes in the cyclic oscillations of blood neutrophils and other blood elements; two of the patients were subsequently treated with G-CSF (5.0 micrograms/kg/d, subcutaneously) and observed for comparable periods of time. Unlike G-CSF treatment, which increased average neutrophil counts more than 20-fold, GM-CSF increased neutrophil counts only modestly, from 1.6- to 3.9-fold, although eosinophilia of varying prominence was induced in each patient. However, at the same time, GM-CSF treatment dampened or eliminated the multilineage oscillations of circulating blood elements (neutrophils, monocytes, platelets, and/or reticulocytes) in each of the patients. In contrast, G-CSF treatment of the same patients markedly amplified the oscillations of neutrophil counts and caused the cycling of other blood elements (monocytes in particular) to become more distinct. These findings support the conclusion that the distinctive cycling of blood cell production in childhood-onset cyclic neutropenia results from abnormalities in the coordinate regulation of both GM-CSF-responsive, multipotential progenitor cells and G-CSF-responsive, lineage-restricted, neutrophil progenitors.  相似文献   
96.
97.
A 42‐year‐old female patient was referred our clinic for investigation of a history of acute retinal artery occlusion. Transthoracic echocardiography showed a cyst‐like, mobile formation on posterior mitral valve leaflet. 2D and real time 3D transesophageal echocardiography showed a flexible circular mobile structure which was attached to posterior mitral valve leaflet. Echocardiographic appearance and morphological characteristics were suggestive of accessory mitral valve tissue.  相似文献   
98.
99.
ObjectiveThe aim of this study was to determine the epidemiologic characteristics of, and the treatments used for, recurrent herpes labialis (RHL) in health students.MethodsA cross-sectional study was conducted with the participation of 333 nursing and midwifery students. Data on the sociodemographic characteristics of the participants, their history of RHL, and the treatments were collected by means of a standard self-reported questionnaire form.ResultsThe point prevalence of RHL was 3.9%, the annual prevalence was 44.7%, and the lifetime prevalence was 52.5%. These prevalences were not related to the participants' place of residence, level of income, school, gender, marital status, or smoking status (p > 0.05). RHL was frequently seen on the right side of the lower lip (17.9%). One third of the students who experienced RHL stated that they had applied treatment to the lesion. However, only 20.1% stated that they had used antiviral therapy. Treatment was recommended by a physician for only 16.1% of the subjects.ConclusionsThe prevalence of RHL was high among the health students, who were considered to represent young adults. Although they were students in a school of health, they lacked knowledge about RHL.  相似文献   
100.
Backround: P‐wave dispersion (P dispersion), defined as the difference between the maximum and the minimum P‐wave duration (P minimum), and maximum P‐wave duration (P maximum) have been used to evaluate the discontinuous propagation of sinus impulse and the prolongation of atrial conduction time respectively. The aim of this study was to investigate whether early assessment of P dispersion predicts paroxysmal atrial fibrillation (AF) in patients with acute anterior wall myocardial infarction (MI). Methods: We prospectively evaluated 147 consecutive patients (45 women, 102 men; aged 55 ± 9 years) with a first acute anterior wall MI. All patients were evaluated by echocardiography to measure the left atrial diameter and left ventricular ejection fraction (LVEF). Electrocardiography was recorded from all patients on admission and every day during hospitalization. Results: AF occurred in 25 patients. In 122 patients, AF did not occur. P maximum was found to be significantly higher in patients with AF than in patients without AF (115 ± 17.3 ms vs 101 ± 14.7 ms, P = 0.001 ). P dispersion also was significantly higher in patients with AF than in patients without AF (50 ± 12.5 ms vs 43 ± 10.1 ms, P = 0.01 ). There was no significant difference between the two groups in P minimum (64 ± 12.5 ms vs 59 ± 11.7 ms, P = 0.057 ). The echocardiographically left atrial diameters were not significantly higher in the patients with AF than those without (25 ± 3.38 mm and 23 ± 3.36 mm , respectively, P = 0.76 ). LVEF was found to be significantly different in the patients who developed AF and in those who did not (37.96 ± 6.18% vs 47.70 ± 6.01%, P = 0.0001 ). Conclusions: Although P maximum and P dispersion are significant predictive factors of AF in patients with acute anterior wall MI in the univariate analysis, on the basis of multivariate analysis, only age and LVEF were independent predictive parameters for AF.  相似文献   
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