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Psychiatric symptoms and medical utilization in primary care patients   总被引:1,自引:0,他引:1  
In two studies, the authors evaluated the impact of psychiatric disorders on medical care utilization in a primary care setting. In the first study, 526 consecutive patients in a teaching hospital primary care practice completed the 18-item RAND Mental Health Inventory to identify clinically significant depression and/or anxiety and a questionnaire about the use of psychiatric treatment and psychoactive medications. The medical utilization of those patients defined as depressed and/ or anxious was compared with those defined as not depressed and/or anxious. Patients identified as depressed and/or anxious reported significantly increased medical utilization, but this was not confirmed by the hospital's computerized record system. In the second study, the authors analyzed medical care utilization for the years before and after the first outpatient psychiatry appointment of a sample of 91 patients referred from the same primary care practice to the hospital's outpatient psychiatry clinic over a 1-year period. In both studies there was not a statistically significant difference in medical utilization among those patients receiving psychiatric treatment. The findings demonstrate the difficulties in examining cost offset in a primary care population and raise questions about it as a realistic outcome measure of the effect of psychiatric treatment.  相似文献   
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Acquired immunodeficiency syndrome (AIDS)-related non-Hodgkin's lymphomas (AIDS-NHLs) consistently derive from B cells, are histologically heterogeneous, and are associated with distinct molecular pathways depending upon histology. Recently, it has been proposed that inactivating mutations of the bax death agonist may contribute to the pathogenesis of human tumors. In particular, among B-cell malignancies, BAX mutations have been detected at a certain frequency in Burkitt lymphomas. This study is aimed at defining the status of the BAX gene throughout the clinicopathologic spectrum of AIDS-NHL (n = 54), including AIDS-related Burkitt lymphoma (n = 14), AIDS-related Burkitt-like lymphoma (n = 8), AIDS-related diffuse large cell lymphoma (n = 15), AIDS-related primary central nervous system lymphoma (n = 6), and AIDS-related primary effusion lymphoma (n = 11). All 6 BAX exons and flanking sequences were subjected to mutational analysis by polymerase chain reaction-single strand conformation polymorphism followed by DNA direct sequencing of positive cases. Mutations of BAX among AIDS-NHL were restricted to a cell line of AIDS-related primary effusion lymphoma, which harbored a frameshift mutation causing the introduction of a proximal stop codon. All other AIDS-NHL displayed wild-type BAX alleles. In order to investigate whether BAX inactivation in AIDS-NHL may occur through mechanisms other than gene mutation, bax protein expression was investigated by Western blot analysis or immunohistochemistry in selected cases. All AIDS-NHL analyzed expressed normal bax proteins. Overall, this study indicates that deregulation of apoptotic control in AIDS-NHL is not caused by BAX alterations. Genes Chromosomes Cancer 27:177-182, 2000.  相似文献   
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A case of malignant lymphoma showing in a lymph node the characteristic morphologic features of the so-called monocytoid B-cell lymphoma (MBCL) is described. This case differs from the reported cases in the literature because atypical cells were observed in the bone marrow biopsy and marrow and peripheral blood smears that were obtained from the patient, a 61-year-old man, during the staging procedures. Lymphocyte surface marker studies on peripheral blood by flow cytometry and DNA analysis revealed a monoclonal population of lambda-positive lymphocytes. The immunophenotype of MBCL cells was studied both in paraffin-embedded lymph node sections by immunoperoxidase method and in peripheral blood by flow cytometric analysis; the cells expressed the SIg with lambda light chain restriction and the HLA-DR antigen; they also had positive results for B-cell-associated antigens, including LN1, LN2, CD 20, CD 22, CD 19, CD 9 but not CD 21, CD 24, and CD 10, T-cell-associated antigens and monocytic markers. In addition, they had negative results for CD 25, CD 38, PCA-1. This report emphasizes that in MBCL, peripheral and marrow involvement may occur at presentation analogous to other low-grade B-cell lymphomas. The immunophenotypic characteristics of MBCL cells, though not pathognomonic, are considered to be helpful in differentiating them from circulating cells of other B-cell lymphomas.  相似文献   
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Summary We performed a comparative immunohisto-cytochemical study of the distribution patterns of laminin and follicular dendritic reticulum cells (DRCs) within their follicular microenvironment in both nodular or diffuse B-cell non Hodgkin's lymphomas (NHLs). Twenty nine cases of immunophenotypically diagnosed B-cell NHLs (19 of follicular center cell origin-FCCL- and 10 of the diffuse well differentiated lymphocytic type-WDLL-) and five reactive lymph nodes with follicular hyperplasia were analyzed by immunoperoxidase and immunofluorescence techniques. Serial frozen sections and cytospin preparations were tested either with single antibodies anti laminin and DRC-1, or paired reagents in double labeling immunofluorescence. Our results indicated consistently that within both the reactive germinal centers and the neoplastic nodules of FCCL laminin immunostaining visualized a punctate-granular pattern apart from the linear vascular basement membrane positivity. Double immunofluorescence assay demonstrated that there was a close parallelism between this laminin staining pattern and DRC-1 distribution showing a well developed DRCs meshwork; in the diffuse tumour areas of both FCCL and WDLL, laminin immunoreactivity was found only in those cases in which nests of DRCs were observed. Double immunofluorescence studies performed on cytospin preparations demonstrated that the groups of cells containing DRC-1 positive cells, contained a positivity for laminin, although within the cell the staining for DRC-1 was intense and diffuse, while that for laminin was granular and more sparse. Our results suggested that these laminin and DRC-1 positive reactive sites may be present on the same cells. Since the reduction in number or loss of both DRCs and their related immunostaining for laminin within the microenvironment was consistently associated with a loss of nodularity by lymphoma cells, whereas nodularity in reactive and neoplastic conditions was associated with a rich DRCs meshwork and the related laminin immunostaining, a trapping function of DRCs exercised in the presence of laminin should be considered.This work was supported in part by a Grant N 87.02799.44 from the Consiglio Nazionale delle Ricerche, Progetto Finalizzato Oncologia, Rome, and by the Associazione Italiana per la Ricerca sul Cancro, Milan, Italy  相似文献   
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BACKGROUND: The unusual occurrence of a metastatic Kaposi's sarcoma (KS) in a lymph node affected by Hodgkin lymphoma (HL) was originally reported when knowledge of the specific virological features of these tumours was lacking. AIM: To re-evaluate this case by assessing whether the simultaneous presence of the two tumours was linked with common aetiopathogenetic factors. METHODS: The presence of EBV was investigated by in situ hybridisation, whereas KS associated herpesvirus (KSHV)/human herpesvirus 8 (HHV-8) was detected by immunohistochemistry. Both viruses were analysed in the case reported, in 30 lymph nodes from patients with classic HL, and in 22 skin biopsies from patients with KS. RESULTS: Consistent with the findings in the HL and KS cases analysed, in the case showing features of both HL and KS in the same lymph node, EBV was detectable only in Reed-Sternberg (RS) cells, but not in KS spindle cells, whereas KSHV/HHV-8 was detectable only in KS spindle cells, and not in RS cells. CONCLUSION: It is probable that the development of KS and HL was related to two independent aetiological cofactors-KSHV/HHV-8 and EBV, respectively-and that the occurrence of the two malignancies in the same patient was merely fortuitous.  相似文献   
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Constitutional mutations in the RB1 gene predispose to retinoblastoma development. Hence genetic screening of retinoblastoma patients and relatives is important for genetic counseling purposes. In addition, RB1 gene mutation studies may help decipher the molecular mechanisms leading to tumors with different degrees of penetrance or expressivity. In the course of genetically screening of 107 hereditary and non-hereditary retinoblastoma patients (11 familiar bilateral, 4 familiar unilateral, 49 sporadic bilateral and 43 sporadic unilateral) and kindred from Spain, Colombia and Cuba, using direct PCR sequencing, we observed 45 distinct mutations and four RB1 deletions in 53 patients (9 familiar bilateral, 2 familiar unilateral, 31 sporadic bilateral and 11 sporadic unilateral). Most of these mutations (26/45, 57%) have not been reported before. In 32 patients, the predisposing mutations correspond to nonsense (mainly CpG transitions) and small insertions or deletions whose expected outcome is a truncated Rb protein that lacks the functional pockets and tail. Five single aminoacid replacements and seventeen mutations affecting splicing sites were also observed in retinoblastoma patients. Two of these sixteen mutations are of unclear pathogenic nature.  相似文献   
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