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The relation between the left atrial systolic pressure waveform and left ventricular end-diastolic pressure was observed in 17 patients who underwent diagnostic cardiac catheterization. Left atrial pressure and left ventricular pressure were simultaneously recorded from a multisensor catheter before and during angiotensin infusion. Left ventricular systolic pressure and left ventricular end-diastolic pressure were 133 +/- 17 and 12.3 +/- 3.2 mm Hg, respectively, before angiotensin infusion and increased to 168 +/- 18 (p less than 0.01) and 19.4 +/- 4.5 mm Hg (p less than 0.01), respectively, during infusion. The left atrial systolic pressure curve consisted of two positive waves--a first wave (A) and a second wave (A'). The A and A' wave pressures were 11.6 +/- 2.3 and 10.2 +/- 3.9 mm Hg, respectively, before angiotensin infusion and 16.5 +/- 2.9 (p less than 0.01) and 18.1 +/- 4.7 mm Hg (p less than 0.01), respectively, during infusion. The ratio of A'/A of left atrial systolic pressure was 0.81 +/- 0.27 before angiotensin infusion and 1.08 +/- 0.14 (p less than 0.01) during infusion. The ratio of A' to A of left atrial systolic pressure was linearly related to left ventricular end-diastolic pressure before and during (p less than 0.01) angiotensin infusion. The amplitude of the A wave exceeded that of the A' wave at normal left ventricular end-diastolic pressures. However, as the left ventricular end-diastolic pressure increased either at rest or during angiotensin infusion, the amplitude of the A' wave increased and often exceeded that of the A wave. These results suggest that the second (A') wave might be attributed to the increased reflection associated with increased left ventricular end-diastolic pressure.  相似文献   
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NOD/LtSzscid/IL‐2Rγ?/? (NSG) mice have advantages in establishing humanized mouse models. However, transferring human PBMCs into these mice often causes lethal GVH disease. In this study, we discovered an improved method for the engraftment of normal or pathological human PBMCs into NSG mice and examined the subsequent induction of specific immune responses. We sequentially transferred human CD4+ memory T (Tm) and B cells obtained from PBMCs of healthy adults or patients with autoimmune diseases into NSG mice. Removing naïve CD4+ T cells from the transferred PBMCs allowed successful engraftment without lethal GVH disease. The transferred Tm cells were found to reside mainly in the spleen and the lymphoid nodules, where they expressed MHC class II molecules and produced cytokines, including IL‐21. Surprisingly, the transferred B cells were also well maintained in the lymphoid organs, underwent de novo class‐switch recombination, and secreted all isotypes of human Igs at significant levels. Moreover, transferring patient‐derived Tm and B cells resulted in sustained production of IgM‐rheumatoid factor and antiaminoacyl transfer RNA synthetase Abs in these mice. These results suggest that transfer of Tm and B cells derived from human PBMCs into NSG mice could be a useful method for the study of human autoimmune mechanisms.  相似文献   
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J Oral Pathol Med (2012) 41 : 444–451 Background: Stromal cells are believed to affect cancer invasion and metastasis. The purpose of this study was to evaluate the distribution of cancer‐associated fibroblasts (CAFs) and the incidence of tumor‐associated macrophages (TAMs) in oral squamous cell carcinoma (OSCC), focusing on clinicopathological factors and patient prognosis, as well as cancer invasion. Methods: The study included 108 patients with OSCC. Anti‐α‐smooth muscle actin, CD68, and CD163 antibodies were used to identify CAFs and TAMs. CAFs were divided into 4 grades on the basis of staining intensity: negative (0), scanty (1), focal (2), and abundant (3). The most intensive areas of macrophage concentration in each tumor invasive stroma were also evaluated. Results: The cancer specimens were divided into Grade 0/1, Grade 2, and Grade 3 on the basis of CAF grade. In addition, they were divided into low‐ and high‐grade groups on the basis of the number of CD68‐positive and CD163‐positive macrophages. The latter were significantly increased in the Grade 2 CAF group compared to the Grade 0/1 group (P = 0.009). Kaplan–Meier and multivariate survival analyses revealed that Grade 2 CAFs (P = 0.003) and high CD163‐positive macrophage levels (P = 0.007) significantly correlated with a poor outcome in patients with OSCC, and that a high CD163‐positive macrophage level was a significant and an independent prognostic factor (P = 0.045). Conclusions: Cancer‐associated fibroblasts and CD163‐positive macrophages may be potential prognostic predictors of OSCC.  相似文献   
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