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Clinical Rheumatology - Thrombotic microangiopathy (TMA) in systemic lupus erythematosus is a rare manifestation associated with activation of the complement system. This study aimed to compare...  相似文献   
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Background: Intravascular ultrasound (IVUS) is currently used to study lesions during transcatheter coronary therapy. However, before dilation some lesions cannot be reached or crossed with the imaging catheter. Hypothesis: This study seeks to elucidate which factors determine the feasibility of IVUS examination before coronary interventions. Methods: Accordingly, 100 consecutive patients undergoing IVUS examination before coronary angioplasty were prospectively studied. The clinical and angiographic characteristics of 77 patients with a successful IVUS study (Group A) were compared with those of 23 patients in whom IVUS was attempted but the target lesion could not be interrogated (Group B). The echogenic characteristics of the target lesion [before (n = 77) or after intervention (in 18 patients in Group B)] were also studied. Results: Patients in Group B were significantly older (62 ± 7 vs. 57 ± 10 years, p < 0.05) and more frequently had stable angina [8 (35%) vs. 9 (11%), p < 0.05]. The distribution of lesions within the coronary tree and angiographic lesion characteristics including length, eccentricity, calcification, bend location, and the American College of Cardiology/American Heart Association classification were similar in both groups. However, proximal tortuosities (>45° at end diastole) were more frequently found in Group B [20 (87%) vs. 47 (61%), p < 0.05]. In addition, by quantitative angiography, patients in Group B had smaller arteries (reference diameter 2.8 ± 0.4 vs. 3.1 ± 0.4 mm, p < 0.05) and more severe lesions (minimal lumen diameter 0.46 ± 0.24 vs. 0.65 ± 0.34 mm, p < 0.05). On IVUS, calcified lesions were more frequently visualized in Group B (61 vs. 38%, p < 0.05). On multivariate analysis, catheter size, baseline minimal lumen diameter, angiographic proximal tortuosities, and lesion calcification on imaging were independent predictors of the feasibility of IVUS studies. Conclusions: Unsuccessful IVUS studies before intervention occur more frequently (1) in vessels with proximal tortuosities or severe lumen narrowing, (2) in lesions that are calcified on IVUS, and (3) when large imaging catheters are used.  相似文献   
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Patel  Jeet  Le  Rebecca T.  Haymes  Dalys  Rao  Dinesh  Fiester  Peter  Hernandez  Mauricio  Jenson  Matthew 《Emergency radiology》2022,29(1):197-205
Emergency Radiology - Dental infections are a common presentation in the emergency department (ED). To help guide clinical management for these infections, the radiologist must be familiar with the...  相似文献   
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We have previously shown that the life cycles of several viruses are influenced by host-cell redox states. Reports of the antioxidant activities of the plant polyphenol resveratrol (RV) prompted us to investigate its effects on influenza virus replication in vitro and in vivo. We found that RV strongly inhibited the replication of influenza virus in MDCK cells but that this activity was not directly related to glutathione-mediated antioxidant activity. Rather, it involved the blockade of the nuclear-cytoplasmic translocation of viral ribonucleoproteins and reduced expression of late viral proteins seemingly related to the inhibition of protein kinase C activity and its dependent pathways. RV also significantly improved survival and decreased pulmonary viral titers in influenza virus-infected mice. No toxic effects were observed in vitro or in vivo. That RV acts by inhibiting a cellular, rather than a viral, function suggests that it could be a particularly valuable anti-influenza drug.  相似文献   
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Assessment of potentially traumatic events and related psychological symptoms in refugee youth is common in epidemiological and intervention research. The objective of this study is to characterize reactions to assessments of trauma exposure and psychological symptoms, including traumatic stress, in refugee youth and their caregivers. Eighty-eight Somali youth and their caregivers participated in a screening and baseline interview for a psychological intervention in three refugee camps in Ethiopia. Participants were asked about their levels of distress prior to, immediately after, and approximately two weeks after completing the interview. Other quantitative and qualitative questions inquired about specific reactions to interview questions and procedures. Children and caregivers became increasingly relaxed over the course of the interview, on average. Few children (5.3%) or caregivers (6.5%) who reported being relaxed at the beginning of the interview became upset by the end of the interview. Some children and caregivers reported that certain assessment questions were upsetting and that feeling upset interfered with their activities. Despite some participants reporting persistent negative reactions, most reported liking and benefitting from the interview. While the majority of refugee youth and their caregivers reported positive experiences associated with completing trauma-related assessments, some reported negative reactions. Researchers and practitioners must consider the necessity, risks, and benefits of including questions about potentially traumatic events and related symptoms that are particularly upsetting in screening, survey research, and clinical assessment. When included, it is important that researchers and practitioners monitor negative reactions to these assessments and connect participants who become distressed with appropriate services.

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Journal of Digital Imaging - Digital images used in the field of ophthalmology are among the most important methods for automatic detection of certain eye diseases. These processes include image...  相似文献   
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