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排序方式: 共有531条查询结果,搜索用时 106 毫秒
1.
Metabolic abnormalities of gastrointestinal mucosa in celiac disease: An in vitro proton nuclear magnetic resonance spectroscopy study 下载免费PDF全文
2.
慢性阻塞性肺疾病的肺生物学标记物研究进展 总被引:1,自引:1,他引:0
与慢性阻塞性肺疾病(COPD)有关的很多炎症细胞、介质,正逐渐为人们所熟知。本文讨论支气管活组织切片、痰液、支气管肺泡灌洗液、呼出气凝物等方面的有关生物标记在COPD研究中的进展。 相似文献
3.
Airway eosinophilia and expression of interleukin-5 protein in asthma and in exacerbations of chronic bronchitis 总被引:6,自引:0,他引:6
M. SAETTA A. DI STEFANO P. MAESTRELLI G. TURATO CE. MAPP M. PIENO G. ZANGUOCHI G. DEL PRETE† L. M. FABBRI 《Clinical and experimental allergy》1996,26(7):766-774
Background An increased nutnber of eosinophils in the bronchial mucosa has been demonstrated both in asthma and in exacerbations of chronic bronchitis. Oiyective To investigate whether the airway eosinophilia present in asthma and in chronic bronchitis during exacerbations is associated with interleukin (IL)-5 protein expression in the bronchial mucosa. Methods We obtained bronchial biopsies in 18 subjects with asthma (four intrinsic, seven extrinsic and seven occupational) and in II subjects with chronic bronchitis examined during an exacerbation. The findings were compared wilh those of bronchial biopsies from 10 subjects with chronic bronchitis examined under baseline conditions and from seven normal subjects, taken as controls. By immunohistochemistry, we assessed the expression of IL-5 protein and the number of eosinophils (EG2), mast cells ftryptase), and T-lymphocytes (CD3) in the submucosa. Results As compared with controls, the number of eosinophils was increased to a similar degree in both asthma (P < 0.001) and in exacerbations of ehronic bronchitis (P < 0.001). whereas the number of I L-5 immunopositive cells was increased significantly only in asthma (P < 0.01). No diflerences were observed in the number of tnast cells and T-lymphocytes between the four groups of subjects examined. Conciusions This study shows that the degree of airway eosinophilia is similar in asthma and in exacerbations of ehronic bronchitis, but only in asthma is it associated with an increased expression of I L-5 protein in the bronchial tnucosa. 相似文献
4.
González-Correa CA Brown BH Smallwood RH Kalia N Stoddard CJ Stephenson TJ Haggie SJ Slater DN Bardhan KD 《Medical & biological engineering & computing》2000,38(4):373-376
It has previously been shown that it is possible to differentiate between squamous and columnar epithelia in rat and resected
human tissues using an impedance probe to makein vitro measurements. This probe can be passed down an endoscope allowing measurements to be made in patients. However, the probe
emerges parallel to the oesophageal wall, with little room to manoeuvre. The conditions of control required to give reliable
readings have been investigated. The importance of pressure applied and the angle of approach to the oesophagus was assessed.
Pressures in the range 26.6 Pa to 46.3 kPa and angles in the range 15–90 degrees were considered. Inin vitro studies it was observed that it was possible to obtain consistent readings with pressures greater than 2.9 kPa and with angles
greater than 15 degrees between the probe and the oesophagus. These conditions can be achievedin vivo, and readings obtained from twelve patients are shown (45 readings on normal squamous, 34 on Barrett's oesophagus and 22
on stomach). At low frequencies (9.6–153.2 kHz), a Mann-Whitney test shows a significant difference (p<0.001) when comparing
the means from squamous and columnar, and also when readings from Barrett's and normal gastric epithelia are compared (p<0.001). 相似文献
5.
Analysis of gene expression patterns in small amounts of human ventricular myocardium by a multiplex RNase protection assay 总被引:3,自引:0,他引:3
C. Mittmann Ursula Münstermann Joachim Weil Michael Böhm Stefan Herzig Christoph Nienaber Thomas Eschenhagen 《Journal of molecular medicine (Berlin, Germany)》1998,76(2):133-140
End-stage human heart failure is associated with changes in expression of steady-state messenger RNA (mRNA) levels. These
changes correspond to alterations in protein levels and myocardial function and may have clinical implications regarding etiology,
clinical state, or prognosis. However, analysis of mRNA levels in endomyocardial biopsies can be accomplished only by the
quantitative polymerase chain reaction, which is difficult to standardize. The aim of the study was to evaluate whether the
RNase protection assay is applicable to measure mRNAs of multiple genes simultaneously in small amounts of ventricular myocardium
comparable to myocardial biopsies. Total RNA was prepared from left ventricular myocardium from terminally failing hearts
with idiopathic (n=9) or ischemic cardiomyopathy (n=7) and from nonfailing control hearts (n=10). mRNA was measured by an optimized RNase protection assay for the β1-adrenoceptor, the stimulatory G protein α-subunit (Gsα), phospholamban, the calcium ATPase of the sarcoplasmic reticulum (SERCA), β-myosin heavy chain (β-MHC), and the atrial natriuretic
peptide (ANP). We extracted 10.7±2.1 μg total RNA from three myocardial biopsies taken in vitro. All of the six genes were
measurable in duplicate in a total of 7 μg RNA. mRNAs of β1-adrenoceptor, phospholamban, and SERCA were lower in failing than in nonfailing myocardium by 50%, 33%, and 42% respectively,
whereas β-MHC and Gsα mRNAs were unchanged. mRNA of ANP was expressed at high levels only in the failing myocardium, providing a highly specific
and sensitive marker for discriminating nonfailing and failing hearts. A direct comparison with ANP and Gsα levels obtained by Northern blot analysis with 7.5 μg total RNA showed a good correlation between the two methods. The RNase
protection assay is thus a suitable method for simultaneous measurements of multiple mRNA levels in human myocardial biopsies.
Changes in mRNA levels closely reflected those identified by other methods using larger amounts of RNA. Increased myocardial
ANP mRNA levels determined by the RNase protection assay may serve as a molecular marker of heart failure.
Received: 12 May 1997 / Accepted: 8 September 1997 相似文献
6.
B. C. J. Hamel R. Happle P. M. Steylen L. A. A. Kolle J. H. Schuurmans Stekhoven J. G. Nijhuis R. Rauskolb I. Anton-Lamprecht 《American journal of medical genetics. Part A》1992,44(6):824-826
Restrictive dermopathy is a rare autosomal recessive lethal skin dysplasia. It has been assumed that the characteristic morphologic abnormalities should allow a reliable prenatal diagnosis on fetal skin biopsies at about 20 weeks pregnancy. We report on a false-negative prenatal diagnosis. © 1992 Wiley-Liss, Inc. 相似文献
7.
S Tseleni-Balafouta A Kyroudi-Voulgari P Paizi-Biza N X Papacharalampous 《Diagnostic cytopathology》1989,5(4):362-365
This study assessed the morphological criteria for the diagnosis of various types of lymphocytic thyroiditis in fine-needle aspirates. Of 950 aspirates, 121 revealed lymphocytic thyroiditis, including Hashimoto's thyroiditis (partly confirmed by serological or histological examination) and focal thyroiditis adjacent to neoplasms. The diagnosis of Hashimoto's thyroiditis was easy when the aspirated material was adequate and contained oxyphilic cells; in the fibrous type, diagnosis was rather difficult. Focal thyroiditis may be confused with Hashimoto's thyroiditis, especially when adjacent to neoplasm. Surgical exploration should be performed in cases of severe lymphocytic thyroiditis revealed by fine-needle aspiration with repeatedly negative antibody titers in order to exclude neoplasm. 相似文献
8.
W H Zhang M Coppleson B R Rose E A Sorich B N Nightingale C H Thompson Y E Cossart P M Bannatyne P M Elliott K H Atkinson 《Journal of medical virology》1988,26(2):163-174
It is now widely accepted that HPV types 16, 18, 31, and 33 are associated with the development of high grade intraepithelial neoplasia and malignant lesions in the cervix. On this basis, the identification of HPV types in cervical scrape samples has been advocated as a supplement to cytological screening tests. However, little is known of the distribution of the virus at different sites in the lower female genital tract or of how this distribution may change during the natural course of HPV infection. In this survey, HPV DNA dot hybridizations and, in some instances, Southern blot hybridizations with mixed HPV 6/11 and 16/18 probes were undertaken to detect HPV DNA in cervical scrapes and biopsies of the cervix, vagina, and vulva. A total of 92 women attending a Sydney hospital were screened: 59 of these patients had cervical disease, either invasive cervical carcinoma (CaCx) or cervical intraepithelial neoplasia (CIN), grades I-III. A group of 33 women who lacked evidence of cervical abnormalities served as controls. HPV DNA, predominantly type 16/18, was detected in the cervical biopsies of 96% of the CaCx patients, 80% of the CIN III patients, and 65% of the CIN I-II patients. In contrast only 9% of the cervical biopsies from the control group contained detectable HPV 6, 11, 16, or 18 DNA. A high proportion of the women with cervical abnormalities had evidence of concurrent vaginal and/or vulval papillomavirus involvement. The significance of these findings for routine screening and subsequent management of patients with HPV-associated cervical disease is discussed. 相似文献
9.
《Pediatric hematology and oncology》2013,30(2):121-135
The aim of this study was to evaluate the diagnostic value of immunohistochemistry with monoclonal antibodies (MoAbs) in detecting residual blast cells in testicular biopsies from children with acute lymphoblastic leukemia (ALL). In a prospective study of 26 patients, testicular biopsies were performed after completion of therapy, and the average follow-up after biopsies was 29 months. After immunostaining, seven patients with negative biopsies on routine histology showed scattered, strongly calla-positive cells as well as cells reacting with anti-B (CD22) MoAb. Among these seven patients with residual blast cells, four had relapsed either in testes (n = 1), bone marrow and testes (n = 1), or in the bone marrow (n = 2). In contrast, among the 15 patients without residual blast cells, all but 1 remained in complete remission. In four other cases no definite conclusion was possible after immunohistochemical study. Four testicular biopsies from patients with occult infiltration were used as positive controls. Negative controls consisted of testicular biopsies from children with testicular ectopia and postmortem testicular tissue specimens. Results suggest that the risk of relapse is significantly higher in patients with positive immunohistochemical findings indicating persistent residual blast cells. However, the predictive value of these findings requires confirmation on a larger number of cases to have therapeutic implications. 相似文献
10.
Paola Carpinetti Elisa Donnard Fabiana Bettoni Paula Asprino Fernanda Koyama Andrei Rozanski Jorge Sabbaga Angelita Habr-Gama Raphael B. Parmigiani Pedro A.F. Galante Rodrigo O. Perez Anamaria A. Camargo 《Oncotarget》2015,6(35):38360-38371
Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is the mainstay treatment for locally advanced rectal cancer. Variable degrees of tumor regression are observed after nCRT and alternative treatment strategies, including close surveillance without immediate surgery, have been investigated to spare patients with complete tumor regression from potentially adverse outcomes of radical surgery. However, clinical and radiological assessment of response does not allow accurate identification of patients with complete response. In addition, surveillance for recurrence is similarly important for these patients, as early detection of recurrence allows salvage resections and adjuvant interventions. We report the use of liquid biopsies and personalized biomarkers for monitoring treatment response to nCRT and detecting residual disease and recurrence in patients with rectal cancer. We sequenced the whole-genome of four rectal tumors to identify patient-specific chromosomal rearrangements that were used to monitor circulating tumor DNA (ctDNA) in liquid biopsies collected at diagnosis and during nCRT and follow-up. We compared ctDNA levels to clinical, radiological and pathological response to nCRT. Our results indicate that personalized biomarkers and liquid biopsies may not be sensitive for the detection of microscopic residual disease. However, it can be efficiently used to monitor treatment response to nCRT and detect disease recurrence, preceding increases in CEA levels and radiological diagnosis. Similar good results were observed when assessing tumor response to systemic therapy and disease progression. Our study supports the use of personalized biomarkers and liquid biopsies to tailor the management of rectal cancer patients, however, replication in a larger cohort is necessary to introduce this strategy into clinical practice. 相似文献