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101.
Background:  Bleeding is one of the main symptoms of internal hemorrhoids. However, the conventional Goligher's classification of internal hemorrhoids does not consider the severity of bleeding. We intended to establish a useful method for evaluating internal hemorrhoids using a colonoscope that reflected the severity of the symptoms.
Methods:  Using a colonoscope in the retroflexed and forward viewing position, 104 patients with symptomatic internal hemorrhoids were evaluated based on the criteria of range, form and red color signs (RCS). Range was determined by the circumferential distribution of internal hemorrhoids and scaled from 0 to 4. Form was determined by size and scaled from 0 to 2. The presence of RCS was also evaluated. Symptoms were determined by interview and scaled from 0 to 3. Patients were treated by endoscopic band ligation (EBL) and were examined endoscopically before and 4 weeks after the treatment.
Results:  Before the treatment, range, form and RCS were significantly correlated to bleeding ( P <  0.01), and form was significantly correlated to prolapse ( P <  0.05). The endoscopic classification scores at 4 weeks after EBL improved significantly (range from 3.25 ± 0.05–0.56 ± 0.08 [ P <  0.01] and form from 2.81 ± 0.04–0.56 ± 0.07 P <  0.01).
Conclusion:  The new endoscopic classification of internal hemorrhoids proved to be closely correlated to symptoms, particularly bleeding, and thus highly useful in evaluating the effectiveness of the treatment.  相似文献   
102.
BACKGROUND: Previous studies have shown a 10-fold discrepancy of self-reported food-induced symptoms and physician-diagnosed food hypersensitivity. Little information is available on the prevalence of food hypersensitivity in unselected paediatric populations. No data were available for German children. OBJECTIVE: To study the perception of food-induced symptoms in the paediatric population, to investigate the allergens accused, to objectify patients' reports, and to identify subgroups at risk of having food-induced allergy (FA) or non-allergic food hypersensitivity (NAFH) reactions. METHODS: This paper presents the data of the paediatric group (0-17 years) of a representative, randomly sampled, cross-sectional population-based survey studying 13 300 inhabitants of the German capital city Berlin regarding food-related symptoms. Instruments included mailed questionnaires, structured telephone interviews, physical examination, skin-prick tests, specific serum IgE and standardized, controlled and blinded oral food challenges. RESULTS: Two thousand three hundred and fifty-four individuals were contacted by mailed questionnaire, 739 (31.4%) responses could be fully evaluated. Four hundred and fifty-five (61.5%) participants reported symptoms related to food ingestion, 284 (38.4%) affirmed reproducible symptoms in the standardized telephone interview. One hundred and eighty-four (24.8%) individuals were fully examined. Reproducible symptoms to food were found in 31 (4.2%) children and adolescents: 26 (3.5%) showed symptoms of FA and five (0.7%) of NAFH. The oral allergy syndrome was most often observed. Foods most commonly identified by oral challenges were apple, hazelnut, soy, kiwi, carrot and wheat. CONCLUSION: The perception of food-related symptoms is common among children and adolescents from the general population. Self-reports could be confirmed in around one out of 10 individuals, still resulting in 4.2% of proven clinical symptoms. However, most reactions were mild and mainly because of pollen-associated FA, while NAFH reactions were less common. Severe IgE-mediated FA was observed in individuals with pre-existing atopic disease, who should be fully investigated for clinically relevant FA.  相似文献   
103.
Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods.  相似文献   
104.
IgE-mediated contact urticaria syndrome (CUS) is one of the manifestations of allergy in childhood atopic dermatitis (AD). Allergens such as foods and animal products penetrate the skin easily. They can then cause urticarial reactions in sensitized individuals. A provocation test system for foods, called the skin application food test (SAFT), has been developed. Over more than 5 years, a group of 175 patients with AD was built-up and investigated in a prospective follow-up study with SAFT. SAFT was more frequently positive in AD children aged 6–2 years than in older children. In several children of this population (Group 1), we repeated SAFT within a period of 1 year. In another unrelated group of children (Group 2–1), we compared the results of 'original' SAFT and SAFT using square chambers (Van der Bend) or Silver patches. In the 3rd group (Group 2–2) we compared'original' SAFT with SAFT using big Finn Chambers. The agreement between the tests was high: in Group 1, we observed 88 to 93% concordant scores, and in Group 2, the scores were 96% to 100%. Statistically, the K coefficient ranged from 0.71–0.87 in Group 1, and from 0.83–1.00 in Group 2. SAFT is therefore highly reproducible. Agreement was at least 88% between the scores (the lowest K value observed was at least 0.71).  相似文献   
105.
BACKGROUND: Food allergies are an important cause of life-threatening hypersensitivity reactions. Oral tolerance can be considered the default immune response to dietary antigens, with immune deviation resulting in allergic sensitization. However, primary sensitization to food allergens may not solely be through the gastrointestinal mucosa, as strong T-helper type 2 (Th2)-biased immunity can result from exposure to protein allergens on barrier-disrupted skin. OBJECTIVE: The purpose of this study was to examine whether exposure to allergens through the skin may interfere with the normal development of oral tolerance and promote allergic sensitization to food proteins. METHODS: Female BALB/c mice were exposed epicutaneously to peanut protein and induction of systemic oral tolerance through high dose feeds of peanut protein was subsequently assessed. Other mice were rendered tolerant prior to epicutaneous peanut exposure. Sensitivity to peanut was determined by assessing delayed-type hypersensitivity, proliferative, cytokine and antibody responses. RESULTS: Epicutaneous exposure to peanut protein induced potent Th2-type immunity with high levels of IL-4 and serum IgE. Primary skin exposure prevented the subsequent induction of oral tolerance to peanut in an antigen-specific manner. Upon oral challenge, mice became further sensitized and developed strong peanut-specific IL-4 and IgE responses. Furthermore, animals with existing tolerance to peanut were partly sensitized following epicutaneous exposure. CONCLUSION: Epicutaneous exposure to peanut protein can prevent induction of oral tolerance, and may even modify existing tolerance to peanut. Epidermal exposure to protein allergens selectively drives Th2-type responses, and as such may promote sensitization to food proteins upon gastrointestinal exposure.  相似文献   
106.
内镜活检对胃癌组织学分类术前诊断的价值   总被引:6,自引:0,他引:6  
目的 探讨内镜活检对胃癌组织学分类术前诊断的价值。方法 术前对141例胃癌患的内镜活检标本分别根据Lauren分类和世界卫生组织(WHO)分类判断组织学分类,并与手术标本结果对照。结果 内镜活检对胃癌Lauren分类术前诊断的准确率为76.6%。对肠型胃癌诊断的敏感性和特异性分别为85.4%和80.6%。而对弥漫型胃癌则分别为82.7%和80.3%,在59例术前诊断为肠型胃癌的病例中,18例(30.5%)在手术标本中呈弥漫性行生长,而在75例术前诊断为弥漫型胃癌的病例中,仅6例(8.0%)术后诊断为肠型胃癌,内镜活检对胃癌WHO分类术前诊断的准确率为87.2%,其中对乳头状/管状腺癌,黏液腺癌和印戒细胞癌的敏感性分别为91.9%。33.3%和66.7%。结论 内镜活检对胃癌组织学分类的术前诊断具有较高的临床应用价值。  相似文献   
107.
The impacts of caffeic acid (3,4‐dihydroxycinnamic acid, CA) on the pharmacokinetics of levodopa (L‐dopa) were studied in rabbits. A single dose of 5/1.25 mg·kg?1 l ‐dopa/carbidopa was administered alone or was co‐administered with three different doses of caffeic acid (2.5, 5, and 10 mg·kg?1), or a single dose of 5 mg·kg?1 caffeic acid was administered alone via an intramuscular route to six rabbits each in a crossover treatment protocol. Plasma levels of l ‐dopa, 3‐O‐methyldopa (3‐OMD), caffeic acid, and ferulic acid were determined and subsequently used to calculate their pharmacokinetic parameters. The results indicated that caffeic acid administered at a dose of 10 mg·kg?1 decreased about 22% of the peripheral formation of 3‐OMD and about 31% of the Cmax of 3‐OMD. In addition, the metabolic ratios (MR, AUC of 3‐OMD/AUC of L‐dopa) decreased by about 22%. Results also indicated that caffeic acid significantly decreased the proportion of 3‐OMD (p < 0.05). In contrast, the parameters of neither caffeic acid nor ferulic acid were significantly affected by l ‐dopa/carbidopa. In conclusion, caffeic acid at a dose of 10 mg·kg?1 can significantly affect the COMT metabolic pathway of L‐dopa. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
108.
Various patterns of ankle fractures that are not accounted for by common classification systems have been the subject of case reports. The first difficulty with these variant patterns is recognizing all associated pathology, followed by the successful application of stable fixation. The purpose of this study was to describe the common morphologic features and ligamentous injuries of a unique variant fracture pattern, as well as the surgical treatment technique and the short-term functional and radiographic outcomes. Of 121 consecutive unstable ankle fractures over a 2-year period, 7 patients were found to have a similar constellation of injuries around the ankle. A vertical shear fracture of the posteromedial tibial rim was the main feature. Six of the 7 also had a fracture of the posterior malleolus. On magnetic resonance imaging, the deltoid and posterior tibiofibular ligaments were intact in all cases. Fractures were treated with open anatomic reduction of the posteromedial and posterior fragments with antiglide plate fixation. All fractures healed at 2 months without loss of reduction, fixation failure, or surgical complications. The average American Academy of Orthopaedic Surgeons lower extremity score was 79 at an average of 8 months' follow-up. The common radiographic and morphologic features associated with this posteromedial fracture indicate that it likely occurs through a common mechanism that involves hyperplantarflexion. The characteristics of this fracture pattern have not been fully described previously, but this ankle fracture variant may occur in up to 6% of cases. Unstable ankle fractures should be evaluated carefully for evidence of posteromedial involvement so appropriate treatment may proceed.  相似文献   
109.
Background: Studies have shown that socioeconomic groups differ in their dietary behaviours, and it has been suggested that these differences partly account for health inequalities between social groups. To-date, however, we have a limited understanding of why socioeconomic groups differ in their dietary behaviours. This paper addresses this issue by examining the relationship between socioeconomic status, food preference (likes and dislikes) and the purchase of 'healthy' food (i.e. food consistent with dietary guideline recommendations). Methods: This study was based on a dual-sample, dual-method research design. One sample was systematically selected from the Australian Commonwealth electoral roll and the data collected using a mail-survey methodology (81% response rate, n =403). The second consisted of a convenience sample of economically disadvantaged people recruited via welfare agencies (response rate unknown, n =70). A mail survey methodology was deemed inappropriate for this sample, so the data were collected by personally delivering the questionnaire to each respondent. Results: Socioeconomic groups differed significantly in their food purchasing choices and preferences. The food choices of respondents in the welfare sample were the least consistent with dietary guideline recommendations, and they reported liking fewer healthy foods (all results were independent of age and sex). Notably, socioeconomic differences in preference explained approximately 10% of the socioeconomic variability in healthy food purchasing behaviour. Conclusion: Whilst it is not clear why socioeconomic groups differ in their food preferences, possible reasons include: reporting bias, differential exposure to healthy food as a consequence of the variable impact of health promotion campaigns, structural and economic barriers to the procurement of these foods, and subculturally specific beliefs, values, meanings, etc.  相似文献   
110.
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems.  相似文献   
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