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排序方式: 共有308条查询结果,搜索用时 15 毫秒
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Stephanie O. Zandieh Amarilis Cespedes Adam Ciarleglio Wallace Bourgeois David M. Rapoport 《The Journal of asthma》2017,54(1):62-68
Objective: Sleep disordered breathing (SDB) has not been well studied in urban adolescents with asthma in community settings. Nor has the association of SDB symptoms and asthma severity been studied. We characterized self-reported symptoms suggesting SDB and investigated the association of SDB symptoms, probable asthma, and asthma severity. Methods: 9,565 adolescents from 21 inner-city high schools were screened for an asthma intervention study. Students reported on symptoms suggesting SDB using questions from the 2007 NHANES, if they were ever diagnosed with asthma, and on asthma symptoms. Using generalized linear mixed models with logit link with school as a random intercept and adjusting for age, gender, and race/ethnicity, we examined associations of SDB symptoms, and demographic characteristics, probable asthma, and asthma severity. Results: 12% reported SDB symptoms. Older and bi-racial participants (compared to Caucasian) had higher odds of symptoms suggesting SDB (p <.001). Compared to those without probable asthma, adolescents with probable asthma had 2.63 greater odds of reporting SDB symptoms (p <.001). Among those with probable asthma, the odds of reporting SDB symptoms increased with asthma severity. When exploring daytime severity and severity due to night wakening separately, results were similar. All results remained significant when controlling for age, gender, and ethnicity. Conclusions: In a large urban community cohort of predominately ethnic minority adolescents, self-reported SDB symptoms were associated with probable asthma and increased asthma severity. This study highlights the importance of SDB as a modifiable co-morbidity of asthma. 相似文献
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Agnes D. Berendsen Lucienne A. Vonk Behrouz Zandieh‐Doulabi Vincent Everts Ruud A. Bank 《Journal of tissue engineering and regenerative medicine》2012,6(9):721-730
Collagen gels are promising scaffolds to prepare an implant for cartilage repair but several parameters, such as collagen concentration and composition as well as cell density, should be carefully considered, as they are reported to affect phenotypic aspects of chondrocytes. In this study we investigated whether the presence of collagen type I or II in gel lattices affects matrix contraction and relative gene expression levels of matrix proteins, MMPs and the subsequent degradation of collagen by goat articular chondrocytes. Only floating collagen I gels, and not those attached or composed of type II collagen, contracted during a culture period of 12 days. This coincided with an upregulation of both Mmp13 and ?14 gene expression, whereas Mmp1 expression was not affected. The release of hydroxyproline in the culture medium, indicating matrix degradation, was increased five‐fold in contracted collagen I gels compared to collagen II gels without contraction. Furthermore, blocking contraction of collagen I gels by cytochalasin B inhibited Mmp13 and ?14 expression and the release of hydroxyproline. The expression of cartilage‐specific ECM genes was decreased in contracted collagen I gels, with increased numbers of cells with an elongated morphology, suggesting that matrix contraction induces dedifferentiation of chondrocytes into fibroblast‐like cells. We conclude that the collagen composition of the gels affects matrix contraction by articular chondrocytes and that matrix contraction induces an increased Mmp13 and ?14 expression as well as matrix degradation. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Kalsbeek A Buijs RM van Schaik R Kaptein E Visser TJ Doulabi BZ Fliers E 《Endocrinology》2005,146(3):1418-1427
Type II deiodinase (D2) plays a key role in regulating thyroid hormone-dependent processes in, among others, the central nervous system (CNS) by accelerating the intracellular conversion of T4 into active T3. Just like the well-known daily rhythm of the hormones of the hypothalamo-pituitary-thyroid axis, D2 activity also appears to show daily variations. However, the mechanisms involved in generating these daily variations, especially in the CNS, are not known. Therefore, we decided to investigate the role the master biological clock, located in the hypothalamus, plays with respect to D2 activity in the rat CNS as well as the role of one of its main hormonal outputs, i.e. plasma corticosterone. D2 activity showed a significant daily rhythm in the pineal and pituitary gland as well as hypothalamic and cortical brain tissue, albeit with a different timing of its acrophase in the different tissues. Ablation of the biological clock abolished the daily variations of D2 activity in all four tissues studied. The main effect of the knockout of the suprachiasmatic nuclei (SCN) was a reduction of nocturnal peak levels in D2 activity. Moreover, contrary to previous observations in SCN-intact animals, in SCN-lesioned animals, the decreased levels of D2 activity are accompanied by decreased plasma levels of the thyroid hormones, suggesting that the SCN separately stimulates D2 activity as well as the hypothalamo-pituitary-thyroid axis. 相似文献
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Radiology report errors occur for many reasons including the use of pre-filled report templates, wrong-word substitution, nonsensical phrases, and missing words. Reports may also contain clinical errors that are not specific to the speech recognition including wrong laterality and gender-specific discrepancies. Our goal was to create a custom algorithm to detect potential gender and laterality mismatch errors and to notify the interpreting radiologists for rapid correction. A JavaScript algorithm was devised to flag gender and laterality mismatch errors by searching the text of the report for keywords and comparing them to parameters within the study’s HL7 metadata (i.e., procedure type, patient sex). The error detection algorithm was retrospectively applied to 82,353 reports 4 months prior to its development and then prospectively to 309,304 reports 15 months after implementation. Flagged reports were reviewed individually by two radiologists for a true gender or laterality error and to determine if the errors were ultimately corrected. There was significant improvement in the number of flagged reports (pre, 198/82,353 [0.24 %]; post, 628/309,304 [0.20 %]; P = 0.04) and reports containing confirmed gender or laterality errors (pre, 116/82,353 [0.014 %]; post, 285/309,304 [0.09 %]; P < 0.0001) after implementing our error notification system. The number of flagged reports containing an error that were ultimately corrected improved dramatically after implementing the notification system (pre, 17/116 [15 %]; post, 239/285 [84 %]; P < 0.0001). We developed a successful automated tool for detecting and notifying radiologists of potential gender and laterality errors, allowing for rapid report correction and reducing the overall rate of report errors. 相似文献
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Razavi Yasaman Keyhanfar Fariborz Haghparast Abbas Shabani Ronak Mehdizadeh Mehdi 《Metabolic brain disease》2021,36(6):1381-1390
Metabolic Brain Disease - Chronic methamphetamine (meth) abuse can lead to certain deficits in the hippocampal function by affecting the hippocampal neurogenesis and plasticity. To determine... 相似文献
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Low gradient ascites: A seven-year course review 总被引:5,自引:0,他引:5
Mansour-Ghanaei F Shafaghi A Bagherzadeh AH Fallah MS 《World journal of gastroenterology : WJG》2005,11(15):2337-2339
AIM: To study the patients with low gradient ascites in hospitals of Guilan Province (northern Iran). METHODS: Patients admitted in hospitals of Guilan Province with low gradient ascites from 1993 to 2000 were enrolled in the study. Serum and ascitic fluid albumin levels were determined by biochemical reactions. The serum-ascitic albumin gradient (SAAG) less than 1.1 g/dL was considered low. Statistical analysis was performed with SPSS 9.0 software and P<0.05 was considered statistically significant. RESULTS: Of the 148 patients enrolled in the study, 72 (48.6%) were males and 76 (51.4%) were females with a mean age of 59.03±13.54 years. Tuberculous peritonitis was the most frequent cause of low gradient ascites in 68 (45.9%). Other most frequent causes were cancer in 62 (41.9%), nephrotic syndrome in 9 (6%), pancreatitis in 6 (4%). Peritoneal cancer was found in 22 (35%), ovarian and gastric cancers were found in 14 (22.5%) and 12 (19.3%), respectively. All of which were the causes of ascites. The mean SAAG was 0.68±0.19 g/dL. The mean serum and ascitic fluid albumin concentrations were higher in tuberculous patients (P<0.006), but lactate dehydrogenase (LDH) level was higher in cancer patients (P<0.0001). In peritoneal tuberculosis, mean ascitic glucose concentration was significantly lower than other patients (P<0.0001). CONCLUSION: Tuberculosis should be considered in all patients with low gradient ascites especially in developing countries (like Iran), as the first cause of ascites. In the approach to patients with low gradient ascites, ascitic fluid glucose, and LDH level are useful indicators for decision making. 相似文献
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