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排序方式: 共有546条查询结果,搜索用时 0 毫秒
1.
Chronic hepatitis C in patients with persistently normal alanine transaminase levels. 总被引:2,自引:0,他引:2
Mitchell L Shiffman Moisés Diago Albert Tran Paul Pockros Robert Reindollar Daniele Prati Maribel Rodríguez-Torres Pilar Lardelli Steven Blotner Stefan Zeuzem 《Clinical gastroenterology and hepatology》2006,4(5):645-652
BACKGROUND & AIMS: Many patients with chronic hepatitis C virus (HCV) have persistently normal serum alanine transaminase (ALT) levels. We compared characteristics of chronic hepatitis C patients with patients with normal and elevated ALT levels using data from 3 randomized phase III trials of peginterferon alfa-2a (40 kDa). METHODS: The characteristics of 480 patients with normal ALT values (on >or=3 occasions without any increases in ALT level over a 6- to 18-month period) and 1993 patients with elevated ALT levels were compared. Sixty-eight of the 480 patients with normal ALT levels were randomized to no treatment and monitored for 72 weeks. RESULTS: More patients with normal ALT levels than patients with elevated ALT levels were women (59% vs 32%; P<.01). The serum HCV RNA titer was significantly lower in patients with normal ALT levels (P<.01 vs in patients with elevated ALT levels). Patients with normal ALT levels had significantly lower inflammation and fibrosis scores on liver biopsy examination than patients with elevated ALT levels, but almost two-thirds had portal fibrosis and 10% had bridging fibrosis. No correlation between baseline ALT activity, HCV RNA level, and liver histology was observed in patients with normal ALT levels. During the 72-week follow-up period, ALT activity elevated above the upper limit of normal in 53% of the untreated patients with normal levels of ALT. None became HCV RNA undetectable. CONCLUSIONS: Chronic hepatitis C patients with normal ALT levels should be evaluated in a similar manner as patients with elevated ALT levels because they are at risk for developing significant liver disease. The decision to treat with peginterferon alfa and ribavirin should be based on multiple factors, rather than on ALT levels alone. 相似文献
2.
Moisés A Arriaga Douglas A Chen Kathleen A Cenci 《Otolaryngology--head and neck surgery》2005,133(3):329-333
OBJECTIVES: To compare the sensitivity of rotational chair (ROTO) versus electronystagmography (ENG) in peripheral vestibular pathology. METHODS: Retrospective chart review. RESULTS: One thousand consecutive patients undergoing evaluation for dizziness and imbalance at a tertiary care referral balance center were reviewed. ROTO was the primary vestibular study used in all patients with ENG used as a confirmatory test at the discretion of the treating physician. A subgroup of 478 patients underwent both ROTO and ENG. Among the patients diagnosed with peripheral vestibulopathy, sensitivity for peripheral vestibulopathy was 71% for ROTO and 31% for ENG. However, specificity was 54% for ROTO and 86% for ENG. CONCLUSIONS: We conclude that in this retrospective cohort with the authors' clinical diagnoses, ROTO is a more sensitive diagnostic study of peripheral vestibular pathology. The higher sensitivity of ROTO and the higher specificity of ENG may support the use of ROTO as the primary vestibular study and ENG as a supplemental vestibular study. Prospective analysis with distinct diagnostic criteria and defined inclusion criteria are necessary before these results can be widely extrapolated. 相似文献
3.
George M Brinson Douglas A Chen Moisés A Arriaga 《Otolaryngology--head and neck surgery》2007,136(3):415-421
OBJECTIVE: This study compares the efficacy of endolymphatic mastoid shunt (EMS) versus endolymphatic sac decompression (ESD) without sac incision for the treatment of Ménière's disease. STUDY DESIGN AND SETTING: The AAO-HNS Guidelines for the Diagnosis and Evaluation of Therapy in Ménière's disease were used to retrospectively identify suitable candidates for the study. All patients who failed medical management and underwent either endolymphatic-mastoid shunt (EMS) (n = 88) or endolymphatic sac decompression (ESD) (n = 108) were selected for review using the AAO-HNS guidelines. The study was carried out at a tertiary care neurotology private practice. RESULTS: EMS and ESD were equally effective in reducing the incidence and severity of vertigo attacks with significant improvement in 67 percent and 66 percent of patients, respectively. CONCLUSION: Both EMS and ESD are effective, nondestructive alternatives for patients who have failed medical management of Ménière's disease with similar long-term hearing outcomes. SIGNIFICANCE: This is the only study within the same institution using AAO-HNS guidelines comparing EMS versus ESD. 相似文献
4.
Hagood JS Prabhakaran P Kumbla P Salazar L MacEwen MW Barker TH Ortiz LA Schoeb T Siegal GP Alexander CB Pardo A Selman M 《The American journal of pathology》2005,167(2):365-379
Fibroblasts consist of heterogeneous subpopulations that have distinct roles in fibrotic responses. Previously we reported enhanced proliferation in response to fibrogenic growth factors and selective activation of latent transforming growth factor (TGF)-beta in fibroblasts lacking cell surface expression of Thy-1 glycoprotein, suggesting that Thy-1 modulates the fibrogenic potential of fibroblasts. Here we report that compared to controls Thy-1-/- C57BL/6 mice displayed more severe histopathological lung fibrosis, greater accumulation of lung collagen, and increased TGF-beta activation in the lungs 14 days after intratracheal bleomycin. The majority of cells demonstrating TGF-beta activation and myofibroblast differentiation in bleomycin-induced lesions were Thy-1-negative. Histological sections from patients with idiopathic pulmonary fibrosis demonstrated absent Thy-1 staining within fibroblastic foci. Normal lung fibroblasts, in both mice and humans, were predominantly Thy-1-positive. The fibrogenic cytokines interleukin-1 and tumor necrosis factor-alpha induced loss of fibroblast Thy-1 surface expression in vitro, which was associated with Thy-1 shedding, Smad phosphorylation, and myofibroblast differentiation. These results suggest that fibrogenic injury promotes loss of lung fibroblast Thy-1 expression, resulting in enhanced fibrogenesis. 相似文献
5.
We show here that expression of Hoxa10 in the presomitic mesoderm is sufficient to confer a Hox group 10 patterning program to the somite, producing vertebrae without ribs, an effect not achieved when Hoxa10 is expressed in the somites. In addition, Hox group 11-dependent vertebral sacralization requires Hoxa11 expression in the presomitic mesoderm, while their caudal differentiation requires that Hoxa11 is expressed in the somites. Therefore, Hox gene patterning activity is different in the somites and presomitic mesoderm, the latter being very prominent for Hox gene-mediated patterning of the axial skeleton. This is further supported by our finding that inactivation of Gbx2, a homeobox-containing gene expressed in the presomitic mesoderm but not in the somites, produced Hox-like phenotypes in the axial skeleton without affecting Hox gene expression. 相似文献
6.
Collaziol D Luz C Dornelles F da Cruz IM Bauer ME 《Mechanisms of ageing and development》2004,125(3):219-227
Ageing has been associated with increased cortisol levels and absolute counts of T lymphocytes with memory phenotype. Although the mechanisms underlying these changes are still unknown, it has been speculated that this could be related to a dysfunction in FAS/CD95 expression in naive or memory cells. In this study, we investigated the role of psychoneuroendocrine variables in regulating CD95 expression on lymphocyte subsets. Forty-six elderly subjects (65-91 years) and 33 young adults (20-40 years) were recruited accordingly the SENIEUR protocol. The psychological status was measured by structured clinical interviews, salivary cortisol was assessed along the day (9, 12 and 22h) and peripheral blood lymphocytes were immunophenotyped. The elderly were more stressed, depressed and anxious than the young subjects. Cortisol levels were increased in the elderly, indicating an activation of the hypothalamic-pituitary-adrenal (HPA) axis. We observed reduced counts of CD45RA+CD95+ cells in the elderly compared to young adults. The elderly subjects also showed a reduced expression of CD3 and CD62L in contrast to increased CD95 expression in CD45RA+ cells. The emotional state was positively correlated with the lymphocyte markers. Our data suggest the healthy ageing is associated with psychoneuroendocrine alterations that may be implicated in the regulation of CD95 expression on peripheral T cells. 相似文献
7.
Mario H. Vargas Luis M. Montaño Beatriz Vanda Patricia Segura Moisés Selman 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(3):278-283
Summary The allergic bronchoconstriction in guinea pigs has been attributed mainly to the release of mast cell mediators. Histamine has been involved in the first minutes of the anaphylactic reaction and new-formed compounds in the subsequent response. In this asthma model the vagal influence has been sparsely investigated. In the present work we evaluated the pharmacological modification of the acute allergic bronchoconstrictor response in guinea pigs sensitized to ovalbumin through aerosol exposure. Pyrilamine (20 g/kg), diethylcarbamazine (a lipoxygenase inhibitor, 10 mg/kg) and dexamethasone (4 mg/kg) each reduced the antigen-induced bronchoconstriction throughout the 30 min studied. Indomethacin (3.1 mg/kg) did not modify the response to the antigen. Atropine (2 mg/kg) plus bilateral vagotomy also diminished this response from 5 min onward. On the other hand, from 5 min ahead pyrilamine-resistant bronchoconstriction was partially inhibited by dexamethasone, and it was almost completely blocked during all of the response when atropine plus bilateral vagotomy were added to dexamethasone. Dipyridamole (an inhibitor of the adenosine uptake, 0.4 mg/kg) enhanced the bronchoconstriction, though this was significant only in the 2–5 min time-interval of the response. These results suggest that histamine and vagal influence play an important role in the whole response to antigen, that other mediators, probably leukotrienes, participate in this response from 5 min onward, and that adenosine could exert a potentiation effect on this response.
Send offprint requests to L. M. Montaño at the Instituto Nacional de Enfermedades Respiratorias 相似文献
8.
Izabela Guimarães Barbosa Natália Pessoa Rocha Aline Silva de Miranda Rodrigo Barreto Huguet Moisés Evandro Bauer Helton José Reis Antônio Lúcio Teixeira 《Revista brasileira de psiquiatria (S?o Paulo, Brazil : 1999)》2013,35(1):67-69
IntroductionBipolar disorder (BD) is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of BD.ObjectiveThe aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls.Methods87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA.ResultsOn average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001), while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03). BDNF plasma levels were not influenced by age, length of illness or current medications.ConclusionsThe present study suggests that long-term BD patients exhibit increased circulating levels of BDNF. 相似文献
9.