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1.
Gangliocytic paragangliomas are rare tumors that almost exclusively occur within the second portion of the duodenum. Although these tumors generally have a benign clinical course, they have the potential to recur or metastasize to regional lymph nodes. The case report presented here describes a 57-year-old female patient with melena, progressive asthenia, anemia, and a mass in the second-third portion of the duodenum that was treated by local excision. The patient was diagnosed with a friable bleeding tumor. The histologic analysis showed that the tumor was a 4 cm gangliocytic paraganglioma without a malignant cell pattern. In the absence of local invasion or distant metastasis, endoscopic resection represents a feasible, curative therapy. Although endoscopic polypectomy is currently considered the treatment of choice, it is not recommended if the size of the tumor is > 3 cm and/or there is active or recent bleeding. Patients diagnosed with a gangliocytic paraganglioma should be closely followed-up for possible local recurrence.  相似文献   
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Prevention Science - This study aimed to evaluate the effectiveness of the drug and violence resistance educational program (PROERD) on short-term secondary outcomes, such as intentions to use...  相似文献   
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This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates.  相似文献   
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We report a case of localized bullous pemphigoid (BP) in a woman patient with primary lymphoedema tarda. There is only one previous case reported of localized pemphigoid in an area of lymphoedema, this being of the cicatricial variant. Slow circulation in the lymphatic vessels, increased capillary permeability with preferential localization of antibodies in the area, and potential cleavage of the epidermal junction due to increased hydrostatic pressure leading to autoimmunity, have all been advocated as possible pathogenic mechanisms. Nevertheless, we consider that the mechanism by which localized pemphigoid arises on lymphoedema remains elusive, based on a previous case of generalized BP sparing an area of postsurgical lymphoedema.  相似文献   
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We report the case of a patient infected with human immunodeficiency virus who presented with fever and a disseminated papulous eruption, diagnosed as cutaneous miliary tuberculosis. The diagnosis was made by histological examination of a skin biopsy, which showed numerous acid‐fast bacilli. A culture grown from a skin biopsy isolated a resistant Mycobacterium tuberculosis strain. The papules disappeared within a few days after starting treatment with pyrazinamide, isoniazid and moxifloxacin.  相似文献   
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In a study of 66 patients with systemic lupus erythematosus (SLE) and 80 controls it was found that the presence of two deficiency (null) alleles of C4 had a significant effect on mean C4 concentrations in serum. In six controls who each had two C4 null alleles the mean C4 concentration in serum was 56% lower than in 43 controls without C4 null alleles; the nadir of the C4 concentration in four patients with SLE with two null alleles was also lower by a mean of 55% than in 32 patients who did not have null alleles. Reduced production of C4 allotypes in subjects with two null alleles may be an important determinant of total C4 concentration in patients with SLE. For optimal interpretation of C4 concentrations in SLE, C4 allotyping appears to be indicated, particularly to identify patients who have two null alleles of C4.  相似文献   
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SETTING: Tuberculosis (TB) is frequent in human immunodeficiency virus (HIV) infected patients, but its treatment is hampered by adverse events and paradoxical reactions. OBJECTIVE: To examine the impact of HIV infection and other factors on the risk and spectrum of adverse events related to anti-tuberculosis treatment in a prospective cohort study conducted between January 2003 and August 2004. RESULTS: Of 105 patients treated for TB, 30 were HIV-infected. The overall incidence of adverse events was 122.5 +/- 18.5 per 100 patient-years (py) and the incidence of severe adverse events was 45.2 +/- 11.3/100 py. Age >50 years (OR 2.2, 95%CI 1.01-4.8, P = 0.046) and HIV infection (OR 3.9, 95%CI 2.1-7.5, P < 0.001) were independently associated with a higher risk of adverse events. Hepatitis (30.5/100 py) and neuropathy (28.6/100 py) were the most frequent adverse events. Hepatitis C virus infection was associated with hepatitis (OR 4.2, 95%CI 1.2-15.0, P = 0.028) and neuropathy with HIV infection (OR 3.8, 95%CI 1.1-13.7, P = 0.040). CONCLUSION: Adverse reactions to anti-tuberculosis drugs are frequent. HIV infection and age >50 years are factors associated with such reactions, while hepatitis C virus infection is a risk factor for hepatitis.  相似文献   
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Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy.  相似文献   
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