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排序方式: 共有893条查询结果,搜索用时 46 毫秒
51.
Ganglioneuromatous polyposis is a very rare intestinal disease which differs from isolated polypoid ganglioneuroma and from diffuse ganglioneuromatosis. Its clinical, endoscopic, microscopic and evolutive features are poorly known. We report three cases of colonic ganglioneuromatous polyposis that illustrated an uncommon diffusion pattern in two men and one woman aged 63-72 who presented with chronic diarrhea. Endoscopic features suggesting the diagnosis were diffuse polyposis predominating in the cecum and right colon, with hyperhemic flat lesions enhanced after indigocarmin instillation. Histological study of the biopsies, and of colectomy specimens, showed a diffuse mucosal ganglioneuromatous proliferation with a few adenomatous polyps. Search for multiple endocrine neoplasia (MEN) type 2b was negative. In conclusion, this polypoid type of diffuse ganglioneuromatosis can be suspected in patients with chronic diarrhea by the special endoscopic aspect of the colonic polyposis. Pathologists should be aware of the distinctive features; diagnosis requires search for adenomas and/or neoplasia by total colopsy in addition to search for MEN 2b. 相似文献
52.
Lacomblez L Dib M Doppler V Faudet A Robin V Salachas F Bensimon G Meininger V 《Thérapie》2002,57(1):65-71
Within the framework of an early drug access programme launched in 1995, a multicentre open study was initiated in France in order to assess, inter alia, the safety of riluzole (50 mg twice a day) in a total of 2069 patients from 28 centres. This programme, a phase IIIb study with direct individual benefit, had two main objectives: to enable patients to receive riluzole therapy pending regulatory approval and commercial availability and to provide further data on the safety of riluzole in a broader ALS population. The most frequent adverse events related to riluzole treatment were: asthenia, nausea and elevation of serum transaminase levels. These observations, similar to data derived from previous pivotal clinical trials, confirm that riluzole has a satisfactory tolerability profile. 相似文献
53.
The bioavailability of a new formulation of chlormadinone acetate (one 10 mg Lutéran tablet) was compared with that of the reference formulation (two 5 mg Lutéran tablets) in a randomised crossover open trial after single oral administration of a 10 mg dose to 12 healthy female volunteers. Measurements of chlormadinone acetate plasma samples were performed by combined gas chromatography/mass spectrometry. Blood samples were collected before administration and up to 144 hours after administration. No significant difference was found between the two formulations in pharmacokinetic parameters. The bioavailability of the two formulations was equivalent in terms of time to maximum concentration (tmax [mean tmax about 2.5 h]) and area under the concentration-time curve (AUC0-infinity) [Weslake's symmetric confidence interval: 19.24%, Schuirmann two one-sided tests procedure: p < 0.05]. No difference was found between the two formulations with regard to clinical safety parameters. 相似文献
54.
Olanders K Sun Z Börjesson A Dib M Andersson E Lasson A Ohlsson T Andersson R 《Shock (Augusta, Ga.)》2002,18(1):86-92
Multiple organ dysfunction syndrome (MODS) is mediated by complex mechanisms in which interactions between activated leukocytes and endothelial cells play a central role. ICAM-1 (intercellular adhesion molecule-1) mediates firm adhesion and transendothelial migration of activated leukocytes from postcapillary venules into the tissue. The present study evaluated the ICAM-1 expression in various organs after 40 min of intestinal ischemia and 1, 3, 6, 12 h of reperfusion (I/R) in the rat, using a dual monoclonal antibody technique (n = 36). Endothelial barrier permeability, using the vascular leakage of radiolabeled human serum albumin was also assessed (n = 12). Neutrophil sequestration in the lungs was quantitated by myeloperoxidase activity and plasma protease inhibitor levels were measured with electroimmunoassay. Significant regional differences were found in ICAM-1 expression between organs, both constitutively and after I/R-injury. The highest constitutive levels were observed in the liver and lungs, followed by the kidneys. The constitutive ICAM-1 expression in the intestines and in the heart was about 1/20 compared with that found in the liver and lungs. The brain and muscle had levels of about 1/150 of that in the liver and lungs. After intestinal I/R, significant increases (17-45%) were found in the lungs, intestines, brain, heart, and muscle. Albumin leakage index (ALI) in all examined organs and myeloperoxidase activity in the lungs increased after I/R-injury. Serum levels of albumin and most protease inhibitors decreased significantly after I/R challenge. Intestinal I/R results in an increase of systemic ICAM-1 expression with marked organ variability. The upregulation of ICAM-1 could represent a crucial step in the adherence- and migration process of activated leukocytes and potentially in the development of tissue injury. 相似文献
55.
The camu-camu, like many other Amazonian fruits, shows an excellent potential for use due to its high vitamin C content, and the use of these natural resources could result in greater development of the Amazonian region. Few studies have been conducted with this fruit, and such studies are necessary in order to develop the required technology to allow for its utilization, thus avoiding or at least decreasing wastage of such a rich raw material. The principle objective of this study was to develop a process for the microencapsulation of camu-camu juice, optimizing the operational conditions. The processing conditions consisted of blanching at a temperature of 95 +/- 2 degrees C for 2 min, followed by cooling in an ice bath and juice extraction using a brush type depulper. The juice was dried with gum arabic or malt dextrin in a mini-spray dryer using an air entry temperature of between 100-160 degrees C and wall material concentration varying between 5-35%, in accordance with a factorial experimental design. Both the air entry temperature and the amount of wall material, plus the interaction between the two, gave significant positive effects at the level of 5% probability on the yield of juice powder. The optimum conditions for juice yield and vitamin C retention were established as 15% wall material and an air entry temperature of 150 degrees C. 相似文献
56.
Fifteen years ago, a role for excitotoxic damage in the pathology of amyotrophic lateral sclerosis (ALS) was postulated. This stimulated the development of riluzole, the only available treatment for the disease. Since then, the identification of abnormal forms of superoxide dismutase as the genetic basis of certain familial forms of ALS has provided a huge impetus to the search for new effective treatments for this devastating disease. Transgenic mouse models have been developed expressing these aberrant mutants that develop a form of motor neurone disease the progress of which can be slowed by riluzole. Studies in these mice have provided evidence for a role for excitotoxic, apoptotic and oxidative processes in the development of pathology. The mice can be used for testing molecules targeting these processes as potential therapies, to allow the most promising to be evaluated in humans. Several such agents are currently in clinical trials. Many previous clinical trials in ALS were insufficiently powered to demonstrate any relevant effect on disease progression. This situation has been to some extent remedied in the more recent trials, which have recruited many hundreds of patients. However, with the exception of studies with riluzole, the results of these have been disappointing. In particular, a number of large trials with neurotrophic agents have revealed no evidence for efficacy. Nonetheless, the need for large multinational trials of long duration limits the number that can be carried out and makes important demands on investment. For this reason, surrogate markers that can be used for rapid screening in patients of potential treatments identified in the transgenic mice are urgently needed. 相似文献
57.
de Raucourt E Barbier C Sinda P Dib M Peltier JY Ternisien C 《American journal of hematology》2003,74(3):187-190
We report two patients who developed acquired factor V (FV) inhibitors not related to exposure to bovine thrombin. Associated conditions were found in one patient (surgery, antibiotic administration) but none in the other one. Bleeding complications occurred only in the patient with idiopathic FV inhibitor, leading to packed red cell infusion. Laboratory findings showed the presence of specific FV inhibitors with titers of 5.5 and 5 Bethesda units, respectively. These two patients received high-dose intravenous immunoglobulin and FV levels normalized within a few days with a concomitant disappearance of FV inhibitors. 相似文献
58.
59.
Abstract – The occurrence of supra- and subgingival calculus, gingival inflammation, periodontal pockets ( 5 mm) and alveolar bone loss was determined in children (10-19 yr) with Down's syndrome (D-S) and in an aged- and sex-matched control group ( n = 39). Of D-S children ( n = 71), 39 of the patients (mean age 15.5 yr) cooperated in a clinical and roentgenologic examination. Alveolar bone loss was determined around incisors and first molars on intraoral radiographs when the distance between cementoenamel junction (GEJ) to alveolar crest (AC) exceeded 2.0 mm. Alveolar bone loss was diagnosed in 39% of the D-S children compared to 3% in the control group ( P <0.001). Of the total number of sites examined on radiographs the distance from CEJ to AC exceeded 2.0 mm in 8% in the D-S group compared to 0.2% in the control group ( P <0.001). The frequency of sites with alveolar bone loss in D-S children was significantly ( P <0.001) higher around the mandibular incisors compared to first molars. The study shows that early signs of periodontitis are frequently seen in D-S children as early as 11 yr of age and the lesions are first diagnosed in the mandibular anterior region. 相似文献
60.
Expression of cytoplasmic islet cell antigens by rat pancreas 总被引:2,自引:0,他引:2
A major problem in standardization of the islet cell cytoplasmic antibody (ICA) assay is variation in sensitivity of the different human pancreas substrates used in individual laboratories. To circumvent this problem, we have developed an assay that utilizes Wistar-Furth rat pancreas as substrate, an anti-islet monoclonal antibody (A2B5) to identify islets and fluorescein-conjugated protein A to identify patient autoantibodies. Sera from 85 control subjects, 27 type I diabetics, and 17 subjects at high risk for developing type I diabetes were assayed in parallel with our standard ICA assay on human pancreas substrate and with Wistar-Furth rat pancreas as substrate. Two sera from control subjects (2 of 85) were ICA positive with rat pancreas compared to 1 of 85 with human pancreas substrate. Sera from 11 of 27 type I diabetics and 15 of 17 sera from high-risk subjects were ICA positive with either rat or human pancreas substrate. A correlation between the specific islet fluorescence readings on human and rat pancreas sections was found with sera from high-risk and control subjects. Furthermore, end-point titers of an ICA-positive serum were identical with both assays. Finally, incubation of an ICA-positive serum with glycolipids, extracted from either human or Wistar-Furth rat pancreas, blocked subsequent ICA binding. These findings suggest that Wistar-Furth rat pancreas expresses an identical or similar autoantigen to human pancreas. 相似文献