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Pelvic actinomycosis associated with intrauterine devices   总被引:1,自引:0,他引:1  
O'Connor  KF; Bagg  MN; Croley  MR; Schabel  SI 《Radiology》1989,170(2):559-560
The authors describe two women with pelvic pain, long-term use of an intrauterine device, and a pelvic mass due to Actinomyces israelii. The diagnostic imaging findings were nonspecific but included mass effect and mucosal irregularity of the rectosigmoid colon at barium enema examination and complex masses and inflammatory changes at computed tomography and magnetic resonance imaging. Radiologists should be aware of the imaging findings of this potentially lethal but curable condition.  相似文献   
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Mangan  KF; D'Alessandro  L 《Blood》1985,66(3):533-541
To define further the role of marrow T suppressor lymphocytes in the pathogenesis of the hypoproliferative anemia in all Rai clinical stages of B cell chronic lymphocytic leukemia (CLL), marrow erythroid progenitor cell (CFU-E and BFU-E) frequency, marrow T gamma lymphocyte frequency per 1,000 nucleated marrow cells, and T cell-erythroid progenitor cell interactions were examined in 30 CLL patients and normal control subjects. As compared with control subjects, decreased numbers of CFU-E and BFU-E were found in patient marrow depleted of neoplastic B cells in all Rai stages of the disease. As a group, Rai stage III through IV patients with or without aplasia (CLL-aplasia) had significantly fewer CFU-E and BFU-E than did Rai O through II stage patients. The numbers of T gamma cells infiltrating CLL marrows were increased 3, 9, and 20 times normal in Rai O through II, Rai III through IV, and CLL-aplasia groups, respectively. Removal of T cells from marrow increased growth of CFU-E and BFU-E in all Rai O through IV patients, but the increase was significant in the CLL-aplasia group only (P less than .05). However, autologous coculture of marrow T cells or T gamma cells but not B cells with marrow B + T-depleted null cells at ratios of 0.2:1 to 1:1 suppressed CFU-E and BFU-E growth in all three patient groups. We conclude that the hypoproliferative anemia occurring in the course of B cell CLL is due to gradual accumulation in the marrow of T gamma lymphocytes which suppress erythroid progenitor cell growth. T gamma cell suppression of erythropoiesis and marrow T gamma cell expansion is detectable in the earliest Rai stages of the disease.  相似文献   
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Unger  EC; Gado  MH; Fulling  KF; Littlefield  JL 《Radiology》1987,162(3):789-795
Magnetic resonance (MR) imaging was performed in five monkeys with experimentally induced acute cerebral infarction to define the MR imaging features and correlate these with computed tomographic (CT) findings, laboratory analysis, and histopathologic studies. Acute infarct (2-4 hours after embolization) was generally visible on MR images but not on CT scans. CT at 24 and 48 hours did show the infarcts. In all cases the infarct was more clearly depicted with MR imaging and was visualized as an area of high signal intensity on T2-weighted images. Spectrometric nuclear MR measurements of the postmortem cerebral tissue confirmed prolongation of both T1 and T2 values similar to that calculated from MR images. At postmortem laboratory testing, the area of infarction detected with MR imaging had decreased specific gravity and increased water content, reflecting edema.  相似文献   
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Volvulus of the caecum is a rare entity in childhood. We report on a case of caecal volvulus in a 6-year-old child, admitted with clinical symptoms of gut occlusion and shock. Outcome was favourable after surgical treatment. The epidemiological, clinical, radiological aspects and therapy are discussed in light of data of the literature.  相似文献   
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IntroductionRecruitment and retention are two of the most important factors in successfully running clinical trials. Many trials encounter problems with both, causing delays or preventing study progress. These issues are greater in older adults and patients with cancer.Materials and methodsWe assessed recruitment and retention in a large, multicentre, observational breast cancer study in older female patients (>70 years, N = 3440). Data collected by the Age Gap study were used to assess rates of, and reasons for, patients not being recruited or retained. Statistical analysis assessed the impact of age as a predictor of recruitment and retention.ResultsBetween February 2013 and June 2018, 6876 patients were screened and 3456 were consented across 56 United Kingdom (UK) breast units. Reasons for non-recruitment included ineligibility, clinician issues, staffing resource issues, patients' lack of interest or time and trial burden. In comparison with the age demographics of patients with breast cancer in the UK, women aged 70–75 years were over-represented compared to older age groups. Logistic regression demonstrated that older age significantly reduced the odds of consent (OR = 0.96, CI: 0.938–0.982; p < 0.001). Multivariate analysis showed that age (p < 0.001), markers of poor functional ability (Eastern Cooperative Oncology Group Performance Status (p = 0.011)) and instrumental activities of daily living (p = 0.026) were significant predictors of withdrawal.DiscussionThis study has demonstrated that selection and attrition bias for age are apparent despite a range of ‘age friendly’ study design measures. Exploration of the underlying reasons for this and development of measures to address this should be the focus of further research.  相似文献   
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