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321.
Although memory for spatial information has often been regarded as unitary, it may be divided into two distinct types: memory for the place where an individual experienced an event and memory for the location of an experienced event within a specific reference object. We used functional magnetic resonance imaging (fMRI) to elucidate the distinctions between the retrieval of these two types of spatial context memory. During scanning, subjects judged the room (Place task) in which a photograph had been presented or the location of the photograph on the computer display (R-L task) during the encoding phase. In a control task, subjects were asked to judge whether the photograph had been presented or not. The left middle frontal gyrus, lateral parietal and occipital regions, and bilateral precunei were found to be active during both the Place task and the R-L task compared with the control task. Critically, the place task, compared with the R-L task, was associated with activations in the right lateral prefrontal gyri, the posterior part of the left parahippocampal gyrus, bilateral retrosplenial and lateral parieto-occipital areas, whereas the R-L task, relative to the place task, with activation only in the right lateral parietal cortex. These findings indicate that the retrieval processes of spatial context memory are not associated with a single network, but may vary and recruit different neural networks depending on the type of spatial information to be retrieved.  相似文献   
322.

Background:

Autonomic function can be evaluated based on the pupillary light reflex (PLR). However, the relationship between PLR and prognosis in patients with heart failure (HF) remains unclear. This study was performed to examine whether PLR could be used as a prognostic indicator in patients with HF.

Methods and Results:

A retrospective review was performed in 535 consecutive Japanese patients hospitalized for acute HF (mean age 66.1 ± 13.7 y). PLR was recorded at least 7 days after hospitalization for HF with the use of a pupilometer. Fifty-three patients died over a median follow-up period of 1.3 years (interquartile range 0.6–2.3 y). After adjustment for several preexisting prognostic factors, including Seattle Heart Failure Score (SHFS), PLR as assessed by recovery time (time to 63% redilation) was independently associated with all-cause mortality (hazard ratio 0.50, 95% confidence interval 0.35–0.73; P < .001). The addition of recovery time to SHFS resulted in a significant increase in the area under the curve on receiver-operating characteristic curve analysis (0.69 vs 0.77; P < .001).

Conclusions:

PLR assessed by recovery time was an independent predictor of mortality and added prognostic information to the SHFS in patients with HF. Our results suggest that PLR may be useful as a new prognostic marker in HF patients.  相似文献   
323.
A 64-year-old man was hospitalized with chief complaints of chest and back pain. A diagnosis of Stanford type A aortic dissection with a false lumen extending from the ascending to the descending aorta was made based on the results of computed tomography (CT). A CT obtained the following day showed resolution of the false lumen and increased brightness of the aortic wall, typical of aortic dissection with intramural hemorrhage. Although previous studies have described a gradual transition from aortic intramural hemorrhage to aortic dissection with a false lumen, there are no reports of the transition from an aortic dissection with a false lumen to the intramural hemorrhage type of aortic dissection. This patient is of interest when considering the pathogenesis of aortic dissection with intramural hemorrhage and the relationship between the intramural hemorrhage and false-lumen types of aortic dissection.  相似文献   
324.
The present paper deals with the occurrence of Legionella bacteria in a variety of man-made environmental waters, including whirlpool bathes, cooling towers and others, from April 1996 to November 2000 in the eastern part of Japan around Tokyo area. A total of 2,895 water samples were examined for the possible occurrence of Legionella, and 904 (31%) were demonstrated to be positive. Among the various water sources, Legionella were frequently detected both in whirlpool bathes and in cooling towers, of which detection rates were 48% and 46%, respectively. More precisely, occurrence of Legionella was higher in private-use whirlpool bathes than those for public-use; namely, the positive rate was 71% in bathes accommodated in private houses, 63% in company's club houses, 62% in company dormitories for employees, and 51% in old-people's homes. Occurrence of Legionella, on the other hand, was less common (< or = 30%) in bathes for public-use such as those installed in hotels and in hot spring facilities. Typing of L. pneumophila serogroups revealed that SG5 (34%) was dominant in whirlpool bath waters followed by SG3 (22%), whereas SG1 (32%) was dominantly found in cooling tower waters.  相似文献   
325.
Donor leukocyte infusion (DLI) is recognized as effective therapy for relapse after stem cell transplantation in patients with chronic myelogenous leukemia (CML). However, the clinical efficacy of DLI in the advanced phase of CML or other types of leukemia has not been clearly defined because of its varying degree of success. We describe a 22-year-old male patient with promyelocytic crisis of CML who had a relapse after peripheral blood stem cell transplantation, under reduced-intensity conditioning, from his HLA 2-antigen-mismatched mother. Complete hematologic remission was obtained after transplantation. However, a relapse that occurred on day 66 posttransplantion was characterized by an increase in number of leukemic promyelocytes with simultaneous exacerbation of disseminated intravascular coagulation (DIC). The patient received DLI containing 1 x 10(7)/kg CD3+ cells on day 73. Because rapid improvement of DIC paralleled the decrease in leukemic cells and because it was observed soon after DLI and before the development of acute graft-versus-host disease (GVHD), we hypothesized that leukemia-specific cells other than natural killer cells or cytotoxic T-cells unrelated to GVHD played a role in the graft-versus-leukemia effect observed in our patient. In addition, this may be the first report of effective correction of DIC by DLI after stem cell transplantation.  相似文献   
326.
Multicentric Castleman disease (MCD) describes a heterogeneous group of disorders involving systemic inflammation, characteristic lymph node histopathology, and multi‐organ dysfunction because of pathologic hypercytokinemia. Whereas Human Herpes Virus‐8 (HHV‐8) drives the hypercytokinemia in a cohort of immunocompromised patients, the etiology of HHV‐8‐negative MCD is idiopathic (iMCD). Recently, a limited series of iMCD cases in Japan sharing a constellation of clinical features, including thrombocytopenia (T), anasarca (A), fever (F), reticulin fibrosis (R), and organomegaly (O) has been described as TAFRO syndrome. Herein, we report clinicopathological findings on 25 patients (14 males and 11 females; 23 Japanese‐born and two US‐born), the largest TAFRO syndrome case series, including the first report of cases from the USA. The median age of onset was 50 years old (range: 23–72). The frequency of each feature was as follows: thrombocytopenia (21/25), anasarca (24/25), fever (21/25), organomegaly (25/25), and reticulin fibrosis (13/16). These patients frequently demonstrated abdominal pain, elevated serum alkaline phosphatase levels, and acute kidney failure. Surprisingly, none of the cases demonstrated marked hypergammoglobulinemia, which is frequently reported in iMCD. Lymph node biopsies revealed atrophic germinal centers with enlarged nuclei of endothelial cells and proliferation of endothelial venules in interfollicular zone. 23 of 25 cases were treated initially with corticosteroids; 12 patients responded poorly and required further therapy. Three patients died during the observation period (median: 9 months) because of disease progression or infections. TAFRO syndrome is a unique subtype of iMCD that demonstrates characteristic clinicopathological findings. Further study to clarify prognosis, pathophysiology, and appropriate treatment is needed. Am. J. Hematol. 91:220–226, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
327.
Matsue  K; Lum  LG; Witherspoon  RP; Storb  R 《Blood》1987,69(1):308-315
Upon activation, B cells express growth and differentiation receptors that permit them to proliferate and differentiate. The aim of this study is to define the nature of the intrinsic B cell defects found in marrow recipients using assays for B cell activation, proliferation, and differentiation. B cells from five short-term (less than three months postgrafting) and 15 long-term (greater than one year postgrafting) marrow recipients (ten with and five without chronic graft-v -host disease [GVHD]) were studied. T cell supernatants (T-sup) were prepared by stimulating normal T cells with 12-0-tetradecanoyl- phorbol-13-acetate (TPA) and phytohemagglutinin. Highly purified B cells were used to assess B cell proliferation responses to T-sup after Staphylococcus aureus Cowan I (SAC) activation and for B cell immunoglobulin production responses to T-sup stimulation after SAC activation. B cells from all five short-term patients and one long-term patient with chronic GVHD did not respond to any stimulation. B cells from two patients with chronic GVHD responded to SAC but had decreased proliferative and differentiative responses to T-sup. B cells from three of seven patients with chronic GVHD and two of five long-term healthy patients could proliferate but could not secrete immunoglobulin in response to SAC plus T-sup stimulation. Furthermore, there was a significant correlation between serum IgG and/or IgM in marrow recipients and the differentiative responses of their B cells to T-sup (P = 0.0075, Fisher's Exact). B cell defects occur at various stages of maturation postgrafting. These defects include the failure to respond to the SAC activation signal, the failure to proliferate in response to T-sup, and the failure to differentiate in response to T-sup. These findings are probably due to the inability of B cells from certain marrow recipients to undergo a second round of ontogeny.  相似文献   
328.
One of the important roles of the prefrontal cortex is inhibition of movement. We applied an event-related functional magnetic resonance imaging (fMRI) technique to observe changes in fMRI signals of the entire brain during a GO/NO-GO task to identify the functional fields activated in relation to the NO-GO decision. Eleven normal subjects participated in the study, which consisted of a random series of 30 GO and 30 NO-GO trials. The subjects were instructed to press a mouse button immediately after the GO signal was presented. However, they were instructed not to move when the NO-GO signal was presented. We detected significant changes in MR signals in relation to the preparation phases, GO responses, and NO-GO responses. The activation fields related to the NO-GO responses were located in the bilateral middle frontal cortices, left dorsal premotor area, left posterior intraparietal cortices, and right occipitotemporal area. The fields of activation in relation to the GO responses were found in the left primary sensorimotor, right cerebellar anterior lobule, bilateral thalamus, and the area from the anterior cingulate to the supplementary motor area (SMA). Brain activations related to the preparation phases were identified in the left dorsal premotor, left lateral occipital, right ventral premotor, right fusiform, and the area from the anterior cingulate to the SMA. The results indicate that brain networks consisting of the bilateral prefrontal, intraparietal, and occipitotemporal cortices may play an important role in executing a NO-GO response.  相似文献   
329.
A rare recurrent chromosomal translocation, t(14;19)(q32;q13), has been identified in a variety of B‐cell malignancies, including chronic lymphocytic leukemia (CLL). We report a unique case of CLL in a patient carrying both trisomy 12 and t(14;19) (q32;q13.1), in whom t(11;14)(q13;q32) developed at relapse. The patient was a 77‐yr‐old woman, and her lymphoma cells at presentation showed CD5+, CD10?, CD19+, CD20+(dim), CD23+, CD38+, and CD11c+. At relapse, the patient's lymphoma cells showed positive staining for cyclin D1 in addition to CD5, CD20, and CD23. Lymphoma cells in specimens at both presentation and relapse were positive for lymphoid enhancer factor 1 (LEF1) and negative for sex‐determining region Y‐box 11 (SOX11). IGH‐BCL1 FISH became positive at relapse. Split FISH assay using BCL1, BCL3, IGH, and CCND1 probes on lymph node specimens obtained at presentation and at autopsy confirmed that the translocation of BCL3 was solely detected in the lymph node at presentation and detected BCL3 and CCND1 translocations in the specimen at autopsy. These observations indicated that IGH‐BCL3 and IGH‐CCND1 had occurred in the same clone after treatment of the disease. In line with immunohistochemical and cytogenetic studies, additional PCR analysis of the FR3‐JH region showed the same sequence derived from IGHV4‐34 in specimens obtained at disease onset and relapse.  相似文献   
330.
In sialolithiasis, the lithiasis is often large and located at the junction of the middle and posterior third of the duct, in the hilum region. In such cases, transoral approach for submandibular lithiases (TASL) is a useful treatment of choice in patients with large submandibular stones that can be palpated bimanually.  相似文献   
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