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Zusammenfassung Es werden eine Patientin mit einer chronischen myeloischen Leuk?mie (CML) und ein Patient mit Haarzell-Leuk?mie in h?matologischer Remission der Leuk?mie unter α-Interferon geschildert, die im Verlauf eine seropositive symmetrische Polyarthritis entwickelten, die die Kriterien für eine rheumatoide Arthritis formal erfüllte. Wegen der guten Effektivit?t des Interferons für die h?matologische Erkrankung wurde diese Therapie nicht abgesetzt und die Arthritis mit niedrigdosiertem Prednisolon bzw. nichtsteroidalen Antirheumatika behandelt. Es handelt sich hier um die 19. und 20. Fallbeschreibung einer symmetrischen Polyarthritis unter α-Interferon-Therapie, die die Kriterien für eine rheumatoide Arthritis erfüllt. M?gliche Ursachen des geh?uften Auftretens von Autoimmunerkrankungen unter Interferontherapie werden diskutiert. Eingegangen: 16. Februar 1999 Akzeptiert: 21. Juni 1999  相似文献   
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In acute myocardial ischemia, regional blood flow and function are proportionally reduced. With prolongation of ischemia, function further declines at unchanged blood flow. We studied the involvement of an inflammatory signal cascade in such progressive dysfunction and whether dysfunction is intrinsic to cardiomyocytes. In 10 pigs, ischemia was induced by adjusting inflow into the cannulated left anterior coronary artery to reduce coronary arterial pressure to 45 mm Hg (ISCH); 4 pigs received the inducible nitric oxide synthase (iNOS) inhibitors aminoguanidine or L-N(6)-(1-iminoethyl)-lysine during ISCH (ISCH+iNOS-Inhib); 6 pigs served as controls (SHAM). Anterior (AW) and posterior (PW) systolic wall thickening (sonomicrometry) were measured. After 6 hours, nitric oxide (NO) synthase (NOS) protein expression, NOS activity, and NO metabolites (nitrite/nitrate/nitroso species) were quantified in biopsies isolated from AW and PW. Cardiomyocyte shortening and intracellular calcium (Indo-1 acetoxymethyl ester) were measured without and with the NOS substrate L-arginine (100 micromol/L). In ISCH, AW wall thickening decreased from 42+/-4% (baseline) to 16+/-3% (6 hours). Wall thickening remained unchanged in ISCH-PW and SHAM-AW/PW. NOS2 (iNOS) protein expression and activity, but not NOS3 (endothelial NO synthase), were increased in ISCH-AW and ISCH-PW. iNOS expression correlated with increased nitrite contents. Cardiomyocyte shortening was reduced in ISCH-AW versus SHAM-AW (4.4+/-0.3% versus 5.6+/-0.3%). L-Arginine reduced cardiomyocyte shortening further in ISCH-AW (to 2.8+/-0.2%) and ISCH-PW (3.4+/-0.4% versus 5.4+/-0.4%) but not in SHAM or in ISCH+iNOS-Inhib; intracellular [Ca(2+)] remained unchanged. With L-arginine, in vitro AW cardiomyocyte shortening correlated with in vivo AW wall thickening (r=0.72). In conclusion, sustained regional ischemia induces myocardial iNOS expression in pigs, which contributes to contractile dysfunction at the cardiomyocyte level.  相似文献   
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Background and objective: Vitamin D deficiency has been reported to be associated with the development of active tuberculosis (TB), but many discrepancies exist among studies. The aims of this study were to compare the frequency of vitamin D deficiency in a Korean population of TB patients and control subjects, and to monitor the changes in vitamin D levels during TB treatment. Methods: Patients with newly diagnosed TB were prospectively enrolled. In addition, healthy volunteers or patients with diseases other than TB were enrolled as controls. Baseline serum 25‐hydroxyvitamin D (25‐OHD) levels were measured in both groups and compared. In the TB patients, measurements of serum 25‐OHD were repeated 1 month after the initiation of treatment and again after completion of treatment. Results: In total, 116 patients with TB and 86 control subjects were recruited. The median 25‐OHD concentration was not different in TB patients at diagnosis (13.9 ng/mL; interquartile range (IQR) 8.80–21.8) compared with control subjects (13.2 ng/mL; IQR 9.6–19.3) (P = 0.97). The frequency of vitamin D deficiency (≤10 ng/mL) was also not different in TB patients (36.2%) compared with controls (27.3%) (P = 0.21). In TB patients, the median 25‐OHD concentration decreased significantly during treatment, to 12.5 ng/mL at 1 month and 11.0 ng/mL on completion of treatment (P = 0.01). Conclusions: Vitamin D levels do not appear to be associated with the development of TB in the Korean population. The median 25‐OHD concentration decreased after treatment for TB.  相似文献   
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Anatomy education is a challenging but vital element in forming future medical professionals. In this work, a personalized and interactive augmented reality system is developed to facilitate education. This system behaves as a “magic mirror” which allows personalized in‐situ visualization of anatomy on the user's body. Real‐time volume visualization of a CT dataset creates the illusion that the user can look inside their body. The system comprises a RGB‐D sensor as a real‐time tracking device to detect the user moving in front of a display. In addition, the magic mirror system shows text information, medical images, and 3D models of organs that the user can interact with. Through the participation of 7 clinicians and 72 students, two user studies were designed to respectively assess the precision and acceptability of the magic mirror system for education. The results of the first study demonstrated that the average precision of the augmented reality overlay on the user body was 0.96 cm, while the results of the second study indicate 86.1% approval for the educational value of the magic mirror, and 91.7% approval for the augmented reality capability of displaying organs in three dimensions. The usefulness of this unique type of personalized augmented reality technology has been demonstrated in this paper. Clin. Anat. 29:446–453, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
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A novel virus, designated Cygnet River virus (CyRV), was isolated in embryonated eggs from Muscovy ducks in South Australia. CyRV morphologically resembles arenaviruses; however, sequencing identified CyRV as an orthomyxovirus. The high mortality rate among ducks co-infected with salmonellae suggests that CyRV may be pathogenic, either alone or in concert with other infections.  相似文献   
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