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1.
Pregnant and parenting adolescents living in inner cities are at risk for acquiring HIV through unprotected sexual activity. In addition to individual risk behaviors, a lack of socioeconomic and other environmental resources create risk environments that make certain communities vulnerable to both adolescent pregnancy and HIV/AIDS. Research indicates that adolescent parents, many who have histories of childhood trauma, may use their experience of young parenthood and the concomitant feelings of parental protectiveness as a source of renewed hope for their future. The purpose of this report is to explore the relationship between history of childhood abuse and high risk behaviors in adolescent Latino mothers and fathers enrolled in a randomized clinical trial of a culturally rooted, couple-focused HIV prevention program. In addition, this report describes the HIV prevention program that was designed specifically for young Latino parents wherein maternal and paternal protectiveness are viewed as intrinsic and developing critical factors that promote resiliency and motivate behavioral change.  相似文献   
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Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:9,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
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Dural sinus thrombosis: study using intermediate field strength MR imaging   总被引:1,自引:0,他引:1  
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus.  相似文献   
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A case of hospital acquired endocarditis due to Acinetobacter calcoaceticus in a severely burned patient is presented. Both aortic and mitral native valves were affected and the organism was resistant to most antimicrobial agents.  相似文献   
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Reiman  TH; Heiken  JP; Totty  WG; Lee  JK 《Radiology》1988,169(2):564-566
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution.  相似文献   
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Low-artifact intravascular devices: MR imaging evaluation   总被引:2,自引:0,他引:2  
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible.  相似文献   
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Human immunodeficiency virus (HIV) type 1 (HIV-1) induces impairment of immune function reflected in reduced lymphocyte proliferative responses. Many other immune changes are induced by HIV-1, but their relationship to lymphocyte functional defects is not known. The present study was designed to correlate functional defects with other HIV disease parameters. Cryopreserved samples from 118 HIV-1-positive subjects and 40 seronegative individuals were examined. The main findings were that impaired proliferative responses to mitogens correlated with (i) decreased cell surface expression of the interleukin-2 receptor (CD25), (ii) increased expression of HLA-DR antigens on CD4 cells, (iii) reduced CD4 and increased CD8 cell numbers, and (iv) increased levels of serum immune complex dissociated p24 antigen. However, impaired function was not associated with increased serum neopterin, beta2-microglobulin, or soluble interleukin-2 receptor or with CD38 antigen expression on lymphocytes. In summary, proliferative functional impairment correlated with some, but not all, immunological changes associated with HIV-1 infection. Most of the phenotypic markers that correlated with altered function are cell surface molecules with significant roles in lymphocyte proliferation and were associated primarily with CD4 cells, compatible with the view that dysregulation of CD4 cells is responsible for impaired function.  相似文献   
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