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BACKGROUND: Gastric lymphoma of mucosa-associated lymphoid tissue (MALT) is related to Helicobacter pylori infection and may depend on this infection for growth. OBJECTIVE: To determine the response of gastric MALT lymphoma to antibiotic treatment. DESIGN: Prospective, uncontrolled treatment trial. SETTING: University hospital referral center and three collaborating university and community hospitals. PATIENTS: 34 patients with stage I or stage II N1 gastric MALT lymphoma. INTERVENTION: Two of three oral antibiotic regimens--1) amoxicillin, 750 mg three times daily, and clarithromycin, 500 mg three times daily; 2)tetracycline, 500 mg four times daily, and clarithromycin, 500 mg three times daily; or 3) tetracycline, 500 mg four times daily, and metronidazole, 500 mg three times daily--were administered sequentially (usually in the order written) for 21 days at baseline and at 8 weeks, along with a proton-pump inhibitor (lansoprazole or omeprazole) and bismuth subsalicylate. MEASUREMENTS: Complete remission was defined as the absence of histopathologic evidence of lymphoma on endoscopic biopsy. Partial remission was defined as a reduction in endoscopic tumor stage or 50% reduction in the size of large tumors. RESULTS: 34 patients were followed for a mean (+/-SD) of 41 +/- 16 months (range, 18 to 70 months) after antibiotic treatment. Of 28 H. pylori-positive patients, 14 (50% [95% CI, 31% to 69%]) achieved complete remission, 8 (29%) achieved partial remission (treatment eventually failed in 4 of the 8), and 10 (36% [CI, 19% to 56%]) did not respond to treatment. Treatment failed in all 6 (100% [CI, 54% to 100%]) H. pylori-negative patients. Patients with endoscopic appearance of gastritis (stage I T1 disease) were most likely to achieve complete remission within 18 months. Tumors in the distal stomach were associated with more favorable response than tumors in the proximal stomach. CONCLUSIONS: A subset of H. pylori-positive gastric MALT lymphomas, including infiltrative tumors, may respond to antibiotics. The likelihood of early complete remission seems to be greatest for superficial and distal tumors.  相似文献   
994.
Open in a separate window OBJECTIVESRecent mortality studies showed worse prognosis in patients (ARNS) with severe aortic regurgitation and preserved ejection fraction (EF) not fulfilling the criteria of current guidelines for surgery. The aim of our study was to analyse left ventricular (LV) systolic and diastolic function and mechanical energetics to find haemodynamic explanations for the reduced prognosis of these patients and to seek a new concept for surgery. METHODSGlobal longitudinal strain (GLS) and echo-based single-beat pressure–volume analyses were performed in patients with ARNS (LV end-diastolic diameter <70 mm, EF >50%, GLS > −19% n = 41), with indication for surgery (ARS; n = 19) and in mild hypertensive controls (C; n = 20). Additionally, end-systolic elastance (LV contractility), stroke work and total energy (pressure–volume area) were calculated.RESULTSARNS demonstrated significantly depressed LV contractility versus C: end-systolic elastance (1.58 ± 0.7 vs 2.54 ± 0.8 mmHg/ml; P < 0.001), despite identical EF (EF: 59 ± 6% vs 59 ± 7%). Accordingly, GLS was decreased [−15.7 ± 2.7% (n = 31) vs −21.2 ± 2.4%; P < 0.001], end-diastolic volume (236 ± 90 vs 136 ± 30 ml; P < 0.001) and diastolic operant stiffness were markedly enlarged, as were pressure–volume area and stroke work, indicating waste of energy. The correlation of GLS versus end-systolic elastance was good (r = −0.66; P < 0.001). ARNS and ARS patients demonstrated similar haemodynamic disorders, whereas only GLS was worse in ARS.CONCLUSIONSARNS patients almost matched the ARS patients in their haemodynamic and energetic deterioration, thereby explaining poor prognosis reported in literature. GLS has been shown to be a reliable surrogate for LV contractility, possibly overestimating contractility due to exhausted preload reserve in aortic regurgitation patients. GLS may outperform conventional echo parameters to predict more precisely the timing of surgery.  相似文献   
995.
IntroductionGiven the widespread use of clinical reasoning (CR) in the healthcare practice, it is essential to inculcate the CR practice in undergraduate pharmacy education which can not only facilitate their clinical education and clinical rotations but can also help them become better clinical pharmacists. There is very limited CR employed in the pharmacy curriculum and practice in the Middle East countries. This study aimed to develop and evaluate CR practice in pharmacy undergraduates in one college of pharmacy in Saudi Arabia.MethodsWe employed a mixed-methods methodology that included two phases. In Phase I, students were introduced to CR practice (‘think aloud’ method) and given geriatric clinical cases which they used in two sessions together with a tutor. This was followed by the writing of SOAP notes using the tutor feedback and completion of a survey that included a self-reflection about their experience of using the CR method. Phase II included face-to-face semi-structured interviews involving selected students that were recruited via convenience sampling to further explore the issues identified in Phase I of the study.ResultsOf the 155 students who completed the survey (response rate 94%), the majority of them agreed that CR using the ‘think aloud’ method was useful in gathering (92%) and interpreting (95%) relevant patient information, identifying medication-related problems (95%), exploring therapeutic options for the problem(s) (93%) and formulating a treatment plan for the patient (90%). Qualitative data analysis of the 12 interviews was consistent with these findings. Furthermore, it provided an insight into the challenges faced by the students in applying this CR method.ConclusionsStudents found the practice of CR using the ‘think aloud’ method helpful in working through given cases and taking clinical decisions. This method can be widely employed in pharmacy education and practice.  相似文献   
996.
Antibodies against sulfoglucuronosyl glycosphingolipids (SGGLs) are known to be present in sera of patients with chronic polyneuropathy associated with IgM paraproteinemia. We recently studied rats sensitized with sulfoglucuronosyl paragloboside (SGPG), a major SGGL species, emulsified with keyhold limpet hemocyanin and Freund's adjuvant. The titer of the IgM class antibodies against SGPG increased up to 1:1,600, while that of the IgG class increased up to 1:800 2 weeks after sensitization. The antibodies showed a high degree of antigenic specificity; no cross-reactivity with other brain glycolipids could be detected. They, however, reacted with human myelin-associated glycoprotein (MAG) by Western blot analysis, but not with rat MAG. These animal models showed minor but clear clinical signs of neuropathy, consisting of mild tail muscle tone loss and walking disabilities. Electrophysiological examination of the sciatic nerves revealed nerve conduction abnormalities which consisted of conduction block and mild decrease in conduction velocity. Thus, our results support the concept that anti-SGPG antibodies may play an important pathogenetic role in this type of chronic neuropathy. © 1996 Wiley-Liss, Inc.  相似文献   
997.
Overexpression of S100A7 (psoriasin), a small calcium-binding protein, has been associated with the development of psoriasis and carcinomas in different types of epithelia, but its precise functions are still unknown. Using human tissue specimens, cultured cell lines, and a mouse model, we found that S100A7 is highly expressed in preinvasive, well-differentiated and early staged human squamous cell carcinoma of the oral cavity (SCCOC), but little or no expression was found in poorly differentiated, later-staged invasive tumors. Interestingly, our results showed that S100A7 inhibits both SCCOC cell proliferation in vitro and tumor growth/invasion in vivo. Furthermore, we demonstrated that S100A7 is associated with the beta-catenin complex, and inhibits beta-catenin signaling by targeting beta-catenin degradation via a noncanonical mechanism that is independent of GSK3beta-mediated phosphorylation. More importantly, our results also indicated that beta-catenin signaling negatively regulates S100A7 expression. Thus, this reciprocal negative regulation between S100A7 and beta-catenin signaling implies their important roles in tumor development and progression. Despite its high levels of expression in early stage SCCOC tumorigenesis, S100A7 actually inhibits SCCOC tumor growth/invasion as well as tumor progression. Downregulation of S100A7 in later stages of tumorigenesis increases beta-catenin signaling, leading to promotion of tumor growth and tumor progression.  相似文献   
998.
999.
Estrogen receptor beta expression in invasive breast cancer   总被引:17,自引:0,他引:17  
The aim of this work was to determine the extent of estrogen receptor beta (ER-beta) expression in invasive breast cancer (BrCA) and whether ER-beta expression is correlated with response to adjuvant hormonal therapy with tamoxifen (AHTT). Immunohistochemical staining (IHC) for estrogen receptor alpha (ER-alpha) and ER-beta was performed on sections of formalin-fixed and paraffin-embedded tissue from 47 unselected invasive breast carcinomas (BrCA). IHC for ER-beta was also performed on sections of BrCA from 118 women who were treated with mastectomy and AHTT. Survival analysis was performed using the Kaplan-Meier method and the log-rank test. Of the 47 unselected BrCA, 17 (36%) were negative for ER-alpha and of these, 8 (47% of ER-alpha negative cases and 17% of all 47 patients) were ER-beta positive. Five of the 8 ER-alpha negative and ER-beta positive cases were positive for ER biochemically. There was no correlation between ER-beta positivity and overall survival in the unselected group. By contrast, in the group of women treated with AHTT, expression of ER-beta in more than 10% of cancer cells was associated with better survival (P = .0077), even in women with node-negative BrCA (P = .0069). In conclusion, our results show that a significant number of women with BrCA are positive for ER-beta only, and may be determined to be ER-negative when currently available IHC is used. ER-beta status is a significant predictor of response to AHTT in women with BrCA. Larger studies with multivariate analysis are needed to confirm these findings.  相似文献   
1000.
This study investigated the use of a nonablative conditioning regimen to decrease toxicity and achieve engraftment of an allogeneic blood stem cell transplant, allowing a graft-versus-malignancy effect to occur. All patients had follicular or small cell lymphocytic lymphoma after relapse from a prior response to conventional chemotherapy. Patients received a preparative regimen of fludarabine (25 mg/m(2) given daily for 5 days or 30 mg/m(2) daily for 3 days) and intravenous cyclophosphamide (1 g/m(2) given daily for 2 days or 750 mg/m(2) daily for 3 days). Nine patients received rituximab in addition to the chemotherapy. Tacrolimus and methotrexate were used for graft-versus-host disease (GVHD) prophylaxis. Twenty patients were studied; their median age was 51 years. Twelve were in complete remission (CR) at transplantation. All patients achieved engraftment of donor cells. The median number of days with severe neutropenia was 6. Only 2 patients required more than one platelet transfusion. The cumulative incidence of acute grade II to IV GVHD was 20%. Only one patient developed acute GVHD of greater than grade II. All patients achieved CR. None have had a relapse of disease, with a median follow-up period of 21 months. The actuarial probability of being alive and in remission at 2 years was 84% (95% confidence interval, 57%-94%). Nonablative chemotherapy with fludarabine/cyclophosphamide followed by allogeneic stem cell transplantation is a promising therapy for indolent lymphoma with minimal toxicity and myelosuppression. Further studies are warranted to compare nonablative allogeneic hematopoietic transplantation with alternative treatment strategies.  相似文献   
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