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BACKGROUND: There are controversies about the importance of biopsies of normal colon mucosa in the investigation of patients with chronic diarrhea. STUDY: Colonic and terminal ileum biopsies of 167 patients were reviewed. In 5 patients, used as controls, colonoscopy was done due to family history of colon cancer. RESULTS: The 5 patients without symptoms had no histologic abnormalities. The histologic findings in 162 patients with chronic diarrhea were as follows: 110 patients (67.9%) with normal histology, microscopic colitis not otherwise specified, and isolated small granulomas; 17 (10.5%) patients had findings of borderline diagnostic significance, including possible collagenous colitis, some features of lymphocytic colitis and melanosis coli; and 35 (21.6%) patients, with diagnostic significant histologic findings as collagenous colitis, lymphocytic colitis, minimal change microscopic colitis, eosinophilic colitis, pericrypt eosinophilic enterocolitis, intestinal spirochetosis, schistosomiasis, and Crohn's disease. Of the 52 patients with either borderline or significant diagnostic abnormalities, in 8 (15.4%) the diagnosis was done only with a proximal study (ascending, transverse, or descending colons). CONCLUSIONS: Histologic lesions of possible diagnostic value could exist in 32.1% of chronic diarrhea patients with normal colonoscopy, which can justify, in certain cases, mucosa biopsies, which might contribute for a more precise etiologic diagnosis; also, the distribution of these histologic changes has pointed out the importance of having all colon segments biopsied.  相似文献   
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The phenomenon of circulating nucleic acids in plasma and serum (CNAPS) has opened many new research lines, which may be framed within two areas of translational research: the development of new techniques for noninvasive prenatal diagnosis; and the study of the pathobiology of many diseases, particularly of cancer. The detection, quantization, and quality analysis of CNAPS have increasingly been found to be interesting and useful in the diagnosis and management of a number of pathologies, at least as complementary tools. The high potential value of CNAPS and the lack of knowledge about their origin and implications have aroused a great interest in many researchers, especially in the last two decades. In fact, in 1999, about 30 published studies focused on this issue, whereas in 2011 it was more than 100.  相似文献   
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Clinical Oral Investigations - The aim of this study was to evaluate the efficacy of supplementary techniques (ultrasonic tip/XP-endo Finisher R) in removing remaining filling materials...  相似文献   
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BACKGROUND: By using a technique designated sham fecaloma, we were able to identify two types of segmentary motor phenomenon: displacement motor phenomena and nondisplacement motor phenomena. The aim of the study contained herein was to evaluate for identification of patients with different types of slow-transit constipation. METHODS: Studies were performed in healthy subjects (n=5; colonic transit time <30 hours) and in constipated patients (n=6; colonic transit time >125 hours; normal rectoanal manometry). A Foley®-type recording probe with two perfused catheters (proximal and distal) was used. A rigid sigmoidoscope was used to place the probe at the sigmoid colon. Values recorded by the distal catheter were subtracted (point by point) from the values recorded by the proximal catheter. Subtraction curves were analyzed to quantify characteristics of displacement motor phenomena (an anally directed pressure gradient) and nondisplacement motor phenomena (an orally directed pressure gradient). RESULTS: All healthy subjects had contractions during the recording session. Displacement motor phenomena were predominant (displacement motor phenomena/30 minutes = 21.2±13.2; range, 3–39). Constipated patients yielded two different patterns: three patients had a very small number of contractions, and three patients had a prevalence of nondisplacement motor phenomena, with numbers similar to numbers of displacement motor phenomena in healthy subjects. A comparison of the patterns of constipated patients revealed a statistically significant difference (P=0.039). CONCLUSION: Sham fecaloma is a simple and safe test. Constipated patients in this study had two different patterns of colonic motility scarce activity without haustration and normal activity without displacement motor phenomena. This method might be useful as a diagnostic tool for clarification of the pathophysiology of severe colonic motor disorders.Supported in part by a grant from Fondo de Investigaciones Sanitarias (FIS) (Spain) and by a grant from Junta de Comunidades de Castilla-La Mancha (Spain).Software and analytic systems used during the course of this study were developed by Prof. P. Carrion, Prof. F. Garcia-Sevilla, and Prof. M. Martinez-Iniesta, all of Castilla-La Mancha University (Department of Electronics) Albacete, Spain.  相似文献   
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In a gasoline-contaminated site in Düsseldorf, Germany a two-year monitoring program was carried out to determine the presence, behavior, and fate of 12 gasoline additives in a total of 96 samples from 14 groundwater wells. The origin of contamination was suspected to be a gasoline spill at a gas station. Target compounds were methyl-tert-butyl ether (MTBE), its main degradation products, tert-butyl alcohol (TBA) and tert-butyl formate (TBF); other gasoline additives, oxygenate dialkyl ethers: Ethyl-tert-butyl ether (ETBE), tert-amyl methyl ether (TAME) and diisopropyl ether (DIPE); aromatics: Benzene, toluene, ethylbenzene and xylenes (BTEX), and other compounds causing odor problems: Dicyclopentadiene and trichloroethylene. Purge and trap coupled with gas chromatography-mass spectrometry permitted detection of ng/L concentrations. Ninety of the 96 samples analyzed contained MTBE at levels varying between 0.01 to 645 microg/L. Five contaminated hot spots were identified with levels up to U.S. Environmental Protection Agency (U.S. EPA) drinking water advisory values (20-40 microg/L) and one of them doubling Danish suggested toxicity level of 350 microg/L at a depth of 11 m. No significant natural attenuation was found in MTBE degradation, although samples with high levels of MTBE contained 0.1 to 440 microg/L of TBA. These levels were attributed to its presence in the contamination source more than MTBE degradation. tert-Butyl alcohol was found to be recalcitrant in groundwater. In all cases, BTEX were at low concentrations or not detected, showing less persistence than MTBE. The monitoring of the contamination plume showed that the distribution of the MTBE and TBA in the aquifer formed a similar vertical concentration profile that was influenced by the groundwater flow direction.  相似文献   
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IntroductionCigarette smoke is the main cause of inflammation in COPD. The mechanisms that differentiate smokers who develop COPD are diverse. In this study, we analyzed the presence of cytokines in the respiratory secretions of smokers with or without COPD and the secretory properties of the differentiated bronchial epithelium obtained from the individuals themselves after exposure to tobacco smoke.Material and methodsTwenty-seven smokers were studied, 12 of whom had COPD that had not been previously treated with steroids. In 11, samples were obtained by means of induced sputum, and the remaining samples were collected from bronchial aspiration after bronchoscopy. Concentrations of IL8, IL13, and TNFα in the supernatant were determined. The results obtained were compared between individuals with and without COPD, and we studied their relationship with the severity of COPD as expressed by the degree of obstruction, dyspnea, presence of hypersecretion and intensity of smoking. Bronchial epithelial cell cultures were obtained by air–liquid interface in 4 smokers. The samples were exposed to increasing concentrations of cigarette smoke (5%–20%) and the epithelial mRNA expressions of Muc5AC, IL8, and TNFα were determined.ResultsCOPD patients had significantly higher values of IL8 than healthy smokers (41 [22] pM vs 21 [12] pM). The values of IL8 correlated significantly with the severity of the obstruction (r=0.6; P<.05), dyspnea (r=0.45; P<.05) and the presence of hypersecretion. There was no relationship between cytokines and the intensity or duration of the tobacco habit. Cigarette smoke produced a dose-dependent increase in the expression of RNAm for Muc5AC, IL8, and TNFα.ConclusionsThere are differences in cytokine production (fundamentally IL8) between smokers and smokers with COPD which could be explained by the direct action of cigarette smoke on epithelial cells.  相似文献   
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ObjectiveThis study aimed to describe the clinical, endoscopic, and histologic characteristics, as well as the response to conventional treatment of pediatric patients with the classical form of eosinophilic esophagitis (EoE).MethodsStudy of clinical, laboratory, endoscopic, and histologic data and response to conventional treatment of 43 previously followed pediatric patients with the classical form of EoE.ResultsA total of 43 patients diagnosed with EoE were included in the study, of which 37 were males (86%), with a mean age of 8.4 years. The most common symptoms were: nausea, vomiting, and abdominal pain (100%) in children younger than 7 years, and loss of appetite (60%), heartburn (52%), and food impaction (48%) in children older than 7 years and adolescents. Regarding the endoscopic findings, 12 (28%) patients had whitish plaques on the esophageal lining, 8 (18.5%) had longitudinal grooves, 2 (4.5%) had concentric rings, 3 (7%) had longitudinal grooves and whitish plaques, and the remaining 18 (42%) had esophageal mucosa with normal appearance. Despite the initial favorable response, 76.7% of patients required more than one course of corticosteroid therapy (systemic or aerosol) and diet (exclusion or elimination of food or elementary allergens). Persistence of eosinophil infiltration was found in some patients despite favorable clinical response.ConclusionsThe classic form of EoE typically shows different symptoms according age range. A significant number of patients required more than one treatment cycle to show clinical remission. Endoscopic and histologic improvement was observed; however, eosinophilic infiltration persisted in some patients.  相似文献   
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We present the results of pulsed and continuous radiofrequency (CRF) of the sphenopalatine ganglion in a case series of 3 patients with chronic cluster headache (CCH). Three patients were referred to our neurosurgical department because of CCH, which was refractory to pharmacological treatment. They underwent pulsed radiofrequency of the sphenopalatine ganglion (PRF‐SPG), and the procedure was performed through an infrazygomatic approach. In the PRF procedures, we applied 2 cycles of PRF at 42°C and 45 V for 120 seconds, with a pulse frequency of 2 Hz and a pulse width of 20 ms. In those procedures where thermocoagulation was carried out, 2 CRF lesions at 80°C for 90 seconds each were performed. Following corticosteroid and local anesthetic (40 mg of methylprednisolone and 1 mL of 1% lidocaine) injection, 2 patients had no pain relief at all, whereas the third one experienced a partial response, which lasted only 1 month and his pain then returned to its baseline level. Thus, this outcome was assessed as a nonsustained partial response. Therefore, all of them underwent a CRF lesioning of the SPG, and after this procedure, they achieved complete pain relief until the end of the follow‐up period. Furthermore, the associated autonomic manifestations disappeared. The 3 patients presented in this case series failed to achieve adequate pain relief after PRF‐SPG. However, these same patients subsequently underwent a successful CRF of the SPG.  相似文献   
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