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991.

Background

The aim of the study was to characterize RV adaptation to varying loading conditions in patients with chronic thromboembolic hypertension (CTEPH) before and after pulmonary endarterectomy (PEA). Nearly 4% of patients with pulmonary embolism develop CTEPH. PEA offers a cure with excellent outcome. By use of cardiovascular magnetic resonance (CMR) combined with hemodynamic measurements pulmonary arterial elastance (Ea-pulm_i), end-systolic right ventricular elastance (Ees-RV_i) and ventriculo-arterial coupling (Ea-pulm_i/Ees-RV_i) can be studied before and after PEA.

Methods

Sixty-five patients (mean age 41 ± 12 years, 28 female) underwent CMR pre- and post-PEA. Ejection fraction (EF), end-diastolic (EDVi), end-systolic (ESVi), and stroke (SVi) volumes were indexed for body surface area. Ea-pulm_i was calculated as pulmonary artery mean pressure (mPAP)/SVi, and Ees-RV_i as mPAP/ESVi.

Results

mPAP decreased from 47 ± 12 to 25 ± 9 mmHg, p =0.0001. Ea-pulm_i was increased before PEA and normalized afterwards (2.8 ± 2.1 vs. 0.85 ± 0.4 mmHg/ml/m2, p =0.0001). Ees-RV_i was depressed before and after PEA (0.72 ± 0.27 vs. 0.66 ± 0.3 mmHg/ml/m2, p =0.13). EF improved from 25 ± 12% to 46 ± 10%, p =0.0001, because ventriculo-arterial coupling was restored (4.2 ± 3 vs. 1.4 ± 0.6, p =0.0001). EDVi and ESVi mproved significantly (EDVi 92 ± 32 to 72 ± 23 ml, p =0.0001; ESVi 69 ± 31 to 41 ± 18 ml, p =0.0001).

Conclusion

RV function is largely determined by afterload and returns to normal once afterload is normalized. This is paralleled by a significant improvement of CMR indices of right ventricular remodelling.  相似文献   
992.
993.
Summary. The immunological phenotype of bone marrow myeloma cells and peripheral blood lymphocytes was evaluated in 38 untreated myeloma patients. A striking increase of monotypic cells expressing the same light chain as the M component was observed in bone marrow from 18/38 (47%) patients. A two-colour analysis clarified that the majority of myeloma cells co-expressed plasma cell and B lymphocyte markers (cyIg, CD38, CD56 and sIg), and were regarded as early-plasma cells (early-PC). In the remaining patients, myeloma cells expressed plasma cell markers only (late-PC). Phenotype corresponded to a distinct morphological pattern: early-PC showed a lympho-plasmocytoid feature with significantly lower diameters than late-PC (12.1 v 14.8 μm, P <0.007). Moreover, the plasma cell labelling index was significantly increased in early-PC patients (1.2 v 0.5%, P <0.04). In peripheral blood from patients with early-PC, monotypic cells co-expressing sIg and CD38, CD56, but not CD19, were also detected. These data suggest a recirculation of early-PC. Myeloma cells maintained their phenotypic pattern during the course of the disease. This observation suggests that the degree of maturation is an intrinsic characteristic of the myeloma cell population in individual patients. The evaluation of prognostic factors, such as β2-microglobulin, C-reactive protein and neopterin, showed a statistically significant increase in the early-PC patients, suggesting a poor outcome. In conclusion, myeloma cell phenotype allows identification of a myeloma variant with aggressive biological and clinical characteristics.  相似文献   
994.
995.
996.
One hundred and forty-two consecutive procedures of percutaneous closure or atrial septal defect were approached by cannulation of the right femoral vein. In 3 of them, the internal jugular vein approach was also necessary because of azygos continuation or unsuccessful device implantation due to inadequate septal alignment. In all of them, device implantation was successfully performed through this alternative percutaneous vascular approach.  相似文献   
997.
998.
Effects of carbonated water on functional dyspepsia and constipation   总被引:4,自引:0,他引:4  
OBJECTIVE: The effects of carbonated beverages on the gastrointestinal tract have been poorly investigated. Therefore, this study aims to assess the effect of carbonated water intake in patients with functional dyspepsia and constipation. METHODS: Twenty-one patients with dyspepsia and secondary constipation were randomized into two groups in a double-blind fashion. One group (10 subjects) drank carbonated water and the other (11 subjects) tap water for almost 15 days. Patients were evaluated for dyspepsia and constipation scores, and underwent a satiety test by a liquid meal, radionuclide gastric emptying, sonographic gallbladder emptying and colonic transit time, using radio-opaque markers. RESULTS: The dyspepsia score was significantly reduced with carbonated water (before = 7.9 +/- 2.8 after = 5.4 +/- 1.7; 0.05) and remained unmodified after tap water (9.7 +/- 5.3 9.9 +/- 4.0). The constipation score also decreased significantly ( 0.05) after carbonated water (16.0 +/- 3.9 12.1 +/- 4.4; 0.05) and was not significantly different with tap water (14.7 +/- 5.1 13.7 +/- 4.7). Satiety was significantly reduced with carbonated water (before = 447 +/- 146 kcal after = 590 +/- 245; 0.01). Gallbladder emptying (delta percent contraction) was significantly improved only with carbonated water (39.9 +/- 16.1% 53.6 +/- 16.7%; 0.01). CONCLUSION: In patients complaining of functional dyspepsia and constipation, carbonated water decreases satiety and improves dyspepsia, constipation and gallbladder emptying.  相似文献   
999.
BACKGROUND/AIMS: Dendritic cells (DCs) play a key role in immune responses through antigen presentation and cytokine secretion. Hepatitis C virus (HCV) is able to escape elimination by the immune system and often establishes a chronic infection. To investigate whether DC dysfunction is involved in this process, we have studied monoycte-derived DCs (Mo-DCs) and plasmacytoid DCs (pDCs), which produce large amounts of IFN-alpha, from chronic HCV patients and healthy donors. METHODS: We have assessed TNF-alpha and IFN-alpha production by pDCs using intracellular staining after total PBMCs stimulation with unmethylated CG dinucleotides (CpGs). The induction of allogeneic T cell proliferation by immature Mo-DCs was measured using the MLR assay. The up-regulation of maturation markers and the production of TNF-alpha in response to LPS were analyzed using flow cytometry and ELISA, respectively. RESULTS: We have detected comparable frequencies of pDCs producing TNF-alpha and IFN-alpha in both chronic HCV patients and healthy donors and we have found that immature Mo-DCs from both patients and donors similarly induce allogeneic T cell proliferation and mature and secrete TNF-alpha in response to LPS. CONCLUSIONS: Our results demonstrate that both pDC and Mo-DCs are not impaired in HCV infected patients.  相似文献   
1000.
We compared the efficacy and tolerability of 24 weeks of treatment with ribavirin 800 mg/day (group A) or 400 mg/day (group B) plus peginterferon alfa-2a 180 mug/week in treatment-naive patients infected with hepatitis C virus (HCV) genotype 2 or 3. A total of 97 of 141 patients randomized to group A (68.8%, 95% confidence interval [CI] 60.5%-76.3%) and 90 of 141 patients randomized to group B (63.8; 95% CI 55.3%-71.7%) achieved a sustained virological response, defined as undetectable serum HCV RNA at the end of untreated follow-up (week 48). Among patients infected with genotype 3, the rate of sustained virological response was 67.5% (95% CI 58.4%-75.6%) in group A and 63.9% (95% CI 54.7%-72.4%) in group B, and among patients infected with genotype 2, the rate of sustained virological response was 77.8% (95% CI 54.2%-93.6%) in group A and 55.6% (95% CI 38.4%-83.7%) in group B. Relapse rates in the 2 treatment groups were similar (17% in group A and 20% in group B). The incidence of adverse events, laboratory abnormalities, and dose reductions was similar in the 2 treatment groups. CONCLUSION: The results suggest that when administered for 24 weeks with peginterferon alfa-2a, ribavirin doses of 400 and 800 mg/day produce equivalent outcomes in patients infected with HCV genotype 3.  相似文献   
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