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Zusammenfassung Hintergrund  Die Implantation eines mechanischen Herzunterstützungssystem (MCSS) bei Patienten mit idiopathischer dilatativer Kardiomyopathie im Endstadium kann zu einer Verbesserung der Herzfunktion führen und die Explantation des Systems erlauben. Wir berichten über die Effekte der ventrikul?ren Entlastung auf die Herzfunktion, die humoralen Anti-β1-Adrenozeptor-Autoantik?rper (A-β1-AAK) sowie die myokardiale Fibrose. Methoden  13 Patienten mit nichtisch?mischer dilatativer Kardiomyopathie im Endstadium (NYHA IV-D) erhielten ein monoventrikul?res (zw?lf Patienten) oder ein biventrikul?res (ein Patient) Herzentlastungssystem. Alle hatten zur Zeit der Implantation einen Cardiac Index <1,61·min−1·m2 K?rperoberfl?che, eine linksventrikul?re Auswurffraktion (LVEF) von <16%, einen linksventrikul?ren enddiastolischen Diameter (LVEDd)>68 mm und einen positiven A-β1-AAK-Nachweis. Echokardiographische Auswertungen, Serumtests auf A-β1-AAK und histologische Untersuchungen hinsichtlich myokardialer Fibrose wurden vor und nach Implantation eines MCSS durchgeführt. Ergebnisse  Die durchschnittliche Unterstützungsdauer betrug 236±201 Tage (30 bis 794 Tage). Innerhalb dieses Zeitraums verbesserte sich die LVEF von ≤15 auf im Durchschnitt 46% und der LVEDd von 74 auf 56 mm. Die A-β1-AAK waren nach im Mittel 11,7 Wochen im Serum nicht mehr nachweisbar. Ein Wiederanstieg konnte auch nach Explantation bei keinem Patienten beobachtet werden. Ein hochpathologischer Fibroseanteil im Myokard war etwa ein Jahr nach Explantation ebenfalls nicht mehr zu beobachten. Ein Patient dekompensierte sechs Monate nach Explantation und wurde daraufhin mit einem externen monoventrikul?ren System unterstützt. Die nachfolgende Transplantation verlief erfolgreich. Ein weiterer Patient starb unmittelbar nach Explantation an der Folge einer an?sthesiologischen Komplikation. Die mittlere Nachbeobachtungsdauer bei elf Patienten nach Explantation betr?gt (Stand 31. 5. 1997) 12,6±9,77 Monate (drei bis 26 Monate). Kumulativ konnten 139 Patientenmonate nachbeobachtet werden. Schlu?folgerung  Bei ausgew?hlten Patienten mit terminaler idiopathischer dilatativer Kardiomyopathie kann durch eine tempor?re mechanische Herzunterstützung eine weitgehende Normalisierung der Herzfunktion erreicht werden. Die pr?operative myokardiale Fibrose ist ein Jahr nach Explantation nicht mehr nachweisbar. Die A-β1-AAK verschwinden in der Phase der mechanischen Entlastung des Herzens und treten nach Explantation des Systems nicht mehr auf. “Weaning” von der mechanischen Herzunterstützung kann eine Alternative zur Herztransplantation darstellen.   相似文献   
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Hyperlipidemia promotes the chronic inflammatory disease atherosclerosis through poorly understood mechanisms. Atherogenic lipoproteins activate platelets, but it is unknown whether platelets contribute to early inflammatory atherosclerotic lesions. To address the role of platelet aggregation in diet-induced vascular disease, we studied beta3 integrin-deficient mice (lacking platelet integrin alphaIIbbeta3 and the widely expressed nonplatelet integrin alphavbeta3) in two models of atherosclerosis, apolipoprotein E (apoE)-null and low-density lipoprotein receptor (LDLR)-null mice. Unexpectedly, a high-fat, Western-type (but not a low-fat) diet caused death in two-thirds of the beta3-/-apoE-/- and half of the beta3-/-LDLR-/- mice due to noninfectious pneumonitis. In animals from both models surviving high-fat feeding, pneumonitis was absent, but aortic atherosclerosis was 2- to 6-fold greater in beta3-/- compared with beta+/+ littermates. Expression of CD36, CD40L, and CD40 was increased in lungs of beta3-/-LDLR-/- mice. Each was also increased in smooth muscle cells cultured from beta3-deficient mice and suppressed by retroviral reconstitution of beta3. These data show that the platelet defect caused by alphaIIbbeta3 deficiency does not impair atherosclerotic lesion initiation. They also suggest that alphavbeta3 has a suppressive effect on inflammation, the loss of which induces atherogenic mediators that are amplified by diet-induced hyperlipidemia.  相似文献   
155.
2019年12月,湖北省武汉市出现首批病因不明的肺炎患者,后经证实,该肺炎系一种病源尚未明确的新型冠状病毒[1]。2020年1月12日,世界卫生组织(WHO)将该新型冠状病毒命名为2019新型冠状病毒(2019 novel coronavirus disease,2019-nCoV),后根据病毒命名原则正式改名为严重急性呼吸综合征冠状病毒2(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2),而由该病毒感染引起的疾病被称为新型冠状病毒肺炎(corona virus disease 2019,COVID-19)。  相似文献   
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BackgroundPneumonia caused by the 2019 novel Coronavirus (COVID‐2019) shares overlapping signs and symptoms, laboratory findings, imaging features with influenza A pneumonia. We aimed to identify their clinical characteristics to help early diagnosis.MethodsWe retrospectively retrieved data for laboratory‐confirmed patients admitted with COVID‐19–induced or influenza A–induced pneumonia from electronic medical records in Ningbo First Hospital, China. We recorded patients'' epidemiological and clinical features, as well as radiologic and laboratory findings.ResultsThe median age of influenza A cohort was higher and it exhibited higher temperature and higher proportion of pleural effusion. COVID‐19 cohort exhibited higher proportions of fatigue, diarrhea and ground‐glass opacity and higher levels of lymphocyte percentage, absolute lymphocyte count, red‐cell count, hemoglobin and albumin and presented lower levels of monocytes, c‐reactive protein, aspartate aminotransferase, alkaline phosphatase, serum creatinine. Multivariate logistic regression analyses showed that fatigue, ground‐glass opacity, and higher level of albumin were independent risk factors for COVID‐19 pneumonia, while older age, higher temperature, and higher level of monocyte count were independent risk factors for influenza A pneumonia.ConclusionsIn terms of COVID‐19 pneumonia and influenza A pneumonia, fatigue, ground‐glass opacity, and higher level of albumin tend to be helpful for diagnosis of COVID‐19 pneumonia, while older age, higher temperature, and higher level of monocyte count tend to be helpful for the diagnosis of influenza A pneumonia.  相似文献   
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OBJECTIVETo investigate the effect on pregnancy outcome of integrating a comprehensive management plan for patients with type 1 diabetes (T1D) into the World Health Organization universal maternal care infrastructure.RESEARCH DESIGN AND METHODSA comprehensive preconception-to-pregnancy management plan for women with T1D was implemented in 11 centers from 8 Chinese cities from 2015 to 2017. Sequential eligible pregnant women (n = 133 out of 137 initially enrolled) with T1D and singleton pregnancies attending these management centers formed the prospective cohort. The main outcome was severe adverse pregnancy outcome comprising maternal mortality, neonatal death, congenital malformations, miscarriage in the second trimester, and stillbirth. We compared pregnancy outcomes in this prospective cohort with two control groups with the same inclusion and exclusion criteria: a retrospective cohort (n = 153) of all eligible pregnant women with T1D attending the same management centers from 2012 to 2014 and a comparison cohort (n = 116) of all eligible pregnant women with T1D receiving routine care from 2015 to 2017 in 11 different centers from 7 cities.RESULTSThe rate of severe adverse pregnancy outcome was lower in the prospective cohort (6.02%) than in either the retrospective cohort (18.30%; adjusted odds ratio [aOR] 0.31 [95% CI 0.13–0.74]) or the contemporaneous comparison cohort (25.00%; aOR 0.22 [95% CI 0.09–0.52]).CONCLUSIONSThe substantial improvements in the prospective cohort are evidence of a potentially clinically important effect of the comprehensive management plan on pregnancy outcomes among Chinese pregnant women with pregestational T1D. This supports the development of similar approaches in other countries.  相似文献   
159.
Previous studies have identified an area in the left lateral fusiform cortex that is highly responsive to written words and has been named the visual word form area (VWFA). However, there is disagreement on the specific functional role of this area in word recognition. Chinese characters, which are dramatically different from Roman alphabets in the visual form and in the form to phonological mapping, provide a unique opportunity to investigate the properties of the VWFA. Specifically, to clarify the orthographic sensitivity in the mid-fusiform cortex, we compared fMRI response amplitudes (Exp. 1) as well as the spatial patterns of response across multiple voxels (Exp. 2) between Chinese characters and stimuli derived from Chinese characters with different orthographic properties. The fMRI response amplitude results suggest the existence of orthographic sensitivity in the VWFA. The results from multi-voxel pattern analysis indicate that spatial distribution of the responses across voxels in the occipitotemporal cortex contained discriminative information between the different types of character-related stimuli. These results together suggest that the orthographic rules are likely represented in a distributed neural network with the VWFA containing the most specific information regarding a stimulus’ orthographic regularity.  相似文献   
160.

Deficits in social skills are common in children with Autism Spectrum Disorder (ASD), and there is an urgent need for effective social skills interventions, especially for improving interactions with typically developing peers. This study examined the effects of a naturalistic behavioral social skills intervention in improving social initiations to peers through a randomized controlled trial. Analyses of multimethod, multi-informant measures indicated that children in the active group (SIMI) demonstrated greater improvement in the types of initiations which were systematically prompted and reinforced during treatment (i.e., behavior regulation). Generalization to joint attention and social interaction initiation types, as well as collateral gains in broader social functioning on clinician- and parent-rated standardized measures were also observed.

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