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排序方式: 共有5236条查询结果,搜索用时 15 毫秒
41.
42.
Inhibition of allergic airways inflammation and airway hyperresponsiveness in mice by dexamethasone: role of eosinophils,IL-5, eotaxin,and IL-13 总被引:4,自引:0,他引:4
Eum SY Maghni K Hamid Q Eidelman DH Campbell H Isogai S Martin JG 《The Journal of allergy and clinical immunology》2003,111(5):1049-1061
BACKGROUND: Glucocorticoids inhibit allergen-induced airway eosinophilia and airway hyperresponsiveness (AHR). Whether glucocorticoids mediate their effects on AHR by inhibiting eotaxin and IL-5, 2 of the principal mediators of eosinophilia, or through IL-13, an important mediator of AHR, has not been established. OBJECTIVE: We sought to investigate the effects of glucocorticoids on airway eosinophilia and the expression of IL-5, eotaxin, and IL-13 in relation to the induction of AHR in a murine model of allergic asthma. METHODS: Dexamethasone (4 mg/kg) and mAbs against eotaxin (80 micro g/kg) and IL-5 (100 micro g/kg) singly and in combination were administered to immunized mice before antigen challenge. Airway responsiveness to methacholine was measured in anesthetized and mechanically ventilated animals. Eotaxin, IL-5, and IL-13 in bronchoalveolar lavage fluid (BALF), lung homogenates, or both were measured by means of ELISA. RESULTS: A single antigen challenge induced AHR that lasted at least 10 days. Eotaxin protein and mRNA levels increased in lung tissue but not in BALF after challenge. IL-5 protein and mRNA levels increased both in BALF and in lung tissue. Dexamethasone reduced airway eosinophilia, AHR, and protein and mRNA for eotaxin and IL-5. Anti-murine eotaxin and anti-IL-5 antibodies alone and in combination reduced the ovalbumin-induced airway eosinophilia significantly but failed to inhibit AHR. Both dexa-methasone and anti-IL-5/anti-eotaxin inhibited the increases in lung IL-13 levels after ovalbumin challenge to a similar extent. CONCLUSION: These findings suggest that the inhibition of AHR by the glucocorticoid dexamethasone does not appear to be explained by effects on eosinophilia, eotaxin, IL-5, or IL-13. 相似文献
43.
Hamid Reza Jamaati Mohammad Behgam Shadmehr Bahare Saidi Adnan Khosravi Mehrdad Arab Forouzan Mohammadi 《Endocrine pathology》2009,20(2):133-136
A 24-year-old man presented to our center with a huge goiter compressing his airway. He had a previous diagnosis of Langerhans cell histiocytosis (LCH) of the lung. Core needle biopsy was consistent with histiocytosis. Thyroidectomy was performed. A very invasive mass was encountered at the time of surgery. Histopathology result was consistent with an invasive papillary cancer of thyroid co-occurring with LCH. Although association of LCH with different malignancies has been reported, co-existing invasive papillary thyroid cancer and LCH is a rare combination. 相似文献
44.
Mohammed Aliya Elamin Sukkar Mohammed Youseif Hamid Azhari Mohammed 《African health sciences》2020,20(1):266
BackgroundObesity in the Sudan is increasing at alarming rate with the tendency of reaching an epidemic proportion in women. It is commonly associated with type 2 diabetes (T2D). Some adipokine hormones such as resistin are associated with obesity.ObjectivesTo study how the levels of resistin, ghrelin and insulin are associated with obesity,fat distribution and (T2D) and to ascertain any interrelationships between them.Subjects and methods150 women, age ≥18 years old, resident in Wad-Madani town, Sudan were participated in the study. They were divided into 3 groups according to body mass index (BMI) value: I (normal weight), II (overweight) and III (obese diabetic). Fasting serum resistin and ghrelin concentrations were measured using ELISA method. Insulin levels were determined by radioimmunoassay(RIA).ResultsThe mean±SD levels of resistin 5.80±4.91ng/mL,Ghrelin107.60±26.67pg/M and Insulin 11.92±8.54mLU/ml in obese diabetic were found to be greater than in normal or overweight women. In normal weight values were 3.07±2.15 ng/mL 83.30±13.38pg/mL, and 6.62±6.77mLU/ml for resistini, ghrelin and Insulin, respectively. Values for overweight women 3.64±2.63 pg/mL 90±17.35 pg/mL and 8.13±7.54 mLU/ml for resistin, ghrelin and insulin respectively.Conclusions and recommendationsIncreased BMI, waist circumference (WC) and hormones (ghrelin and resistin) were associated with insulin resistance. Further studies are needed to accept or refute these findings. 相似文献
45.
Kendall J. Burdick Joy D. Cogan Lynette C. Rives Amy K. Robertson Mary E. Koziura Elly Brokamp Laura Duncan Vickie Hannig Jean Pfotenhauer Rena Vanzo Michael S. Paul Anna Bican Thomas Morgan Jessica Duis John H. Newman Rizwan Hamid John A. Phillips III Undiagnosed Diseases Network 《American journal of medical genetics. Part A》2020,182(6):1400-1406
While exome sequencing (ES) is commonly the final diagnostic step in clinical genetics, it may miss diagnoses. To clarify the limitations of ES, we investigated the diagnostic yield of genetic tests beyond ES in our Undiagnosed Diseases Network (UDN) participants. We reviewed the yield of additional genetic testing including genome sequencing (GS), copy number variant (CNV), noncoding variant (NCV), repeat expansion (RE), or methylation testing in UDN cases with nondiagnostic ES results. Overall, 36/54 (67%) of total diagnoses were based on clinical findings and coding variants found by ES and 3/54 (6%) were based on clinical findings only. The remaining 15/54 (28%) required testing beyond ES. Of these, 7/15 (47%) had NCV, 6/15 (40%) CNV, and 2/15 (13%) had a RE or a DNA methylation disorder. Thus 18/54 (33%) of diagnoses were not solved exclusively by ES. Several methods were needed to detect and/or confirm the functional effects of the variants missed by ES, and in some cases by GS. These results indicate that tests to detect elusive variants should be considered after nondiagnostic preliminary steps. Further studies are needed to determine the cost‐effectiveness of tests beyond ES that provide diagnoses and insights to possible treatment. 相似文献
46.
47.
Freeman A Hamid S Morris L Vowler S Rushbrook S Wight DG Coleman N Alexander GJ 《Journal of viral hepatitis》2003,10(5):345-350
Summary. To test the hypothesis that hepatitis C virus (HCV) might induce hepatocyte proliferation directly, thereby predisposing HCV carriers to cirrhosis and hepatocellular carcinoma, we have used a new method to identify proliferating hepatocytes, employing a novel monoclonal antibody to minichromosome maintenance (Mcm) proteins, essential components of the pre-replication complex. Antibody to Ki-67, a conventional marker of cell division, was also studied. Eighty-seven patients with chronic HCV infection and a broad spectrum of histological change were studied. Proliferation was observed rarely in hepatocytes from normal liver from healthy controls (always less than 0.01%). However, proliferating hepatocytes were detected in all HCV-infected patients and the proportion of hepatocytes expressing Mcm-2 (3–40%) always exceeded that expressing Ki-67 (1–14%) and correlated positively with increasing stage of fibrosis ( P = 0.0001) and viral replication ( P = 0.0004). There were weaker but significant associations between the proportion of hepatocytes expressing Mcm-2 and inflammatory indices including interface hepatitis, portal tract inflammation, lobular inflammation and steatosis. There was no association between the proportion of hepatocytes expressing Mcm-2 and age, gender or past alcohol consumption, but there was a weak association with current consumption of alcohol ( P = 0.0067). The proportion of Ki-67 hepatocytes did not correlate with any clinical, laboratory or histological parameter. Mcm-2 was also detected in bile duct cells, sinusoidal lining cells and infiltrating lymphocytes, but at low frequency. These data indicate first, that Mcm-2 is a more sensitive marker of hepatocyte proliferation than Ki-67, second that many hepatocytes in chronic HCV infection have entered the cell cycle and third, suggest that interference with the hepatocyte cell cycle might be an alternative approach to therapy. 相似文献
48.
Hatamabadi HR Darbandsar Mazandarani P Abdalvand A Arhami Dolatabadi A Amini A Kariman H Derakhshanfar H 《The American journal of emergency medicine》2012,30(7):1141-1145
Introduction
Many of critically ill patients receive medical care for prolonged periods in emergency department (ED). This study is the evaluation of efficiency of Acute Physiology and Chronic Health Evaluation (APACHE) III scoring system in predicting mortality rate in these patients.Methods
This study was conducted between 2008 and 2009 in Tehran, Iran. One hundred subjects were enrolled in the study. Cases were chosen from patients in need of intensive care unit (ICU) bed who were kept in the ED. The APACHE III scores and predicted and observed mortality rates were calculated using the information from patients' files, interviews with the patients' families, and performing required physical examinations and laboratory tests.Results
The age of the patients and the ED length of stay were 66.07 (±19.92) years and 5.11 (±3.79) days, respectively. The mean (±SD) of APACHE III score of the patients was 58.89 (±18.24). The predicted mortality rate was calculated to be 32.73%, whereas the observed mortality rate was 55%. The mean (±SD) of APACHE III score of survivors and nonsurvivors was 48.63 (±16.35) and 67.63 (±14.84), respectively (P < .001). Furthermore, the ED length of stay was 3.20 (±1.34) and 6.57 (±4.4) days in survivors vs nonsurvivors, respectively (P < .001).Conclusion
The APACHE III score and ED lengths of stay were higher in this study compared with other studies. This could be ascribed to more critical patients presenting to the study center and also limited ICU bed availability. This study was indicative of applicability of APACHE III scoring system in evaluating the quality of care and prognosis of ED patients in need of ICU. 相似文献49.
Alireza Khatony Nahid Dehghan Nayery Fazlolaah Ahmadi Hamid Haghani Katri Vehvilainen-Julkunen 《BMC medical education》2009,9(1):41
Background
Information about web-based education outcomes in comparison with a face-to-face format can help researchers and tutors prepare and deliver future web-based or face-to-face courses more efficiently. The aim of this study was to compare the effectiveness of web-based and face-to-face continuing education methods in improving nurses' knowledge about AIDS. 相似文献50.
Parisa Rangraz Hamid Behnam Pooya Sobhebidari Jahan Tavakkoli 《Ultrasound in medicine & biology》2014,40(12):2841-2850
High-intensity focused ultrasound (HIFU) induces thermal lesions by increasing the tissue temperature in a tight focal region. The main ultrasound imaging techniques currently used to monitor HIFU treatment are standard pulse-echo B-mode ultrasound imaging, ultrasound temperature estimation and elastography-based methods. The present study was carried out on ex vivo animal tissue samples, in which backscattered radiofrequency (RF) signals were acquired in real time at time instances before, during and after HIFU treatment. The manifold learning algorithm, a non-linear dimensionality reduction method, was applied to RF signals which construct B-mode images to detect the HIFU-induced changes among the image frames obtained during HIFU treatment. In this approach, the embedded non-linear information in the region of interest of sequential images is represented in a 2-D manifold with the Isomap algorithm, and each image is depicted as a point on the reconstructed manifold. Four distinct regions are chosen in the manifold corresponding to the four phases of HIFU treatment (before HIFU treatment, during HIFU treatment, immediately after HIFU treatment and 10-min after HIFU treatment). It was found that disorganization of the points is achieved by increasing the acoustic power, and if the thermal lesion has been formed, the regions of points related to pre- and post-HIFU significantly differ. Moreover, the manifold embedding was repeated on 2-D moving windows in RF data envelopes related to pre- and post-HIFU exposure data frames. It was concluded that if mean values of the points related to pre- and post-exposure frames in the reconstructed manifold are estimated, and if the Euclidean distance between these two mean values is calculated and the sliding window is moved and this procedure is repeated for the whole image, a new image based on the Euclidean distance can be formed in which the HIFU thermal lesion is detectable. 相似文献