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排序方式: 共有735条查询结果,搜索用时 15 毫秒
81.
Youth are particularly vulnerable to acquiring HIV, yet reaching them with HIV prevention interventions and engaging and retaining those infected in care and treatment remains a challenge. We sought to determine the incidence rate of loss to follow-up (LTFU) and explore socio-demographic and clinical characteristics associated with LTFU among HIV-positive youth aged 15–21 years accessing outpatient care and treatment clinics in Kisumu, Kenya. Between July 2007 and September 2010, youth were enrolled into two different HIV care and treatment clinics, one youth specific and the other family oriented. An individual was defined as LTFU when absent from the HIV treatment clinic for ≥?4 months regardless of their antiretroviral treatment status. The incidence rate of LTFU was calculated and Cox regression analysis used to identify factors associated with LTFU. A total of 924 youth (79% female) were enrolled, with a median age of 20 years (IQR 18–21). Over half, (529 (57%)), were documented as LTFU, of whom 139 (26%) were LTFU immediately after enrolment. The overall incidence rate of LTFU was 52.9 per 100 person-years (p-y). Factors associated with LTFU were pregnancy during the study period (crude HR 0.68, 95% CI 0.53–0.89); CD4 cell count >350 (adjusted hazard ratios (AHR) 0.59, 95% CI 0.39–0.90); not being on antiretroviral therapy (AHR 4.0, 95% CI 2.70–5.88); and non-disclosure of HIV infection status (AHR 1.43, 95% CI 1.10–1.89). The clinic of enrolment, age, marital status, employment status, WHO clinical disease stage and education level were not associated with LTFU. Interventions to identify and enrol youth into care earlier, support disclosure, and initiate ART earlier may improve retention of youth and need further investigation. Further research is also needed to explore the reasons for LTFU from care among HIV-infected youth and the true outcomes of these patients. 相似文献
82.
Faltynek CR; Princler GL; Rossio JL; Ruscetti FW; Maluish AE; Abrams PG; Foon KA 《Blood》1986,67(4):1077-1082
Patients with hairy cell leukemia (HCL) and chronic lymphocytic leukemia (CLL) were treated with recombinant interferon alpha A (rIFN- alpha A). The binding of iodinated recombinant interferon-alpha to baseline samples of peripheral blood mononuclear cells (PBMCs) from the leukemia patients was compared with clinical responsiveness to rIFN- alpha A. HCL patients (8/10) responded to rIFN-alpha A therapy, whereas none (0/10) of the CLL patients studied responded. The PBMCs from the eight responsive HCL patients bound approximately twice as much iodinated interferon as the PBMCs from nonresponsive CLL patients. This difference was due to more high-affinity receptors per cell with no difference in the affinity of the interferon-receptor interaction. However, because PBMCs from HCL patients were larger than PBMCs from CLL patients, the cell surface receptor density was similar. The leukemic cells from one of the two nonresponsive HCL patients bound iodinated interferon similarly to the cells from the responsive HCL patients, whereas the leukemic cells from the other nonresponsive HCL patient bound considerably less. The rapidity of response of the HCL patients did not correlate with the level of binding of iodinated interferon. Our results suggest that the absolute number of interferon receptors per cell may be only one of several important parameters in the response to rIFN-alpha A therapy, and that the responsiveness of a particular lymphoproliferative disease or a particular patient to rIFN- alpha A therapy cannot be predicted or explained solely by the degree of interaction between IFN and its cell surface receptor. 相似文献
83.
Identification of cytidine diphosphodiesters in erythrocytes from a patient with pyrimidine nucleotidase deficiency 总被引:1,自引:0,他引:1
Pyrimidine 5'-nucleotidase deficient (PND) erythrocytes contain elevated levels of pyrimidine nucleotides and relatively normal purine nucleotide levels. The composition of this nucleotide pool has been examined by others, but not all of the abnormal red cell metabolites in this disorder were identified. We have isolated and positively confirmed the identity of cytidine diphosphate (CDP)-choline and CDP- ethanolamine from PND red cells using methods including proton FT-NMR, spectroscopy, and comparative mass spectrometry. The concentrations of these and other pyrimidine nucleotidase-deficient erythrocyte nucleotides were determined using anion-exchange high performance liquid chromatography and ultraviolet (u.v.) detection. The pyrimidine diphosphodiesters appear to be the most prominent abnormal pyrimidine nucleotides in PND red cells, accounting for 55% of the total red cell pyrimidine nucleotides in this disorder. It is proposed that these abnormal phosphodiesters may be related to the accelerated hemolysis in PND. 相似文献
84.
Takayasu arteritis presenting as a pulmonary-renal syndrome 总被引:2,自引:0,他引:2
Savage BJ Gupta RK Angle J Okusa MD 《The American journal of the medical sciences》2003,325(5):275-281
Takayasu arteritis is an uncommon disease with a variety of presentations. We report a case of Takayasu arteritis with a presentation of a pulmonary-renal syndrome in a 22-year-old woman. She presented in acute respiratory failure with hemoptysis and acute renal failure; interestingly, however, the renal biopsy was normal. Magnetic resonance angiography (MRA) showed significant narrowing in the distal abdominal aorta with bilateral renal and common iliac artery occlusions. Thoracic and abdominal angiogram confirmed MRA findings of type IV Takayasu arteritis. Percutaneous transluminal angioplasty of the left renal artery normalized kidney function. The initial presentation of Takayasu arteritis as a pulmonary-renal syndrome with severe acute renal failure and diffuse pulmonary hemorrhage is unusual; to our knowledge, this has not been described previously in the literature. We provide a clinical review of Takayasu arteritis and a discussion of systemic manifestations pertinent to the case. 相似文献
85.
Modulation of in vitro and in vivo T-cell responses by transferrin- gallium and gallium nitrate 总被引:2,自引:0,他引:2
Gallium is a group IIIa metal that has efficacy in the therapy of malignant disorders such as lymphoma and urothelial tract tumors. Preclinical studies also indicate a role for gallium in autoimmune disorders, suggesting that gallium is able to modulate T-cell immune reactivity. The purpose of this study was to examine the in vitro and in vivo immunomodulatory action of gallium on T-cell function. Since gallium binds to transferrin in vivo, in vitro studies evaluated the effect of transferrin-gallium (Tf-Ga) on human T cells. Tf-Ga inhibited the mitogen-induced proliferative response of peripheral blood mononuclear cells (PBMC) in a dose-dependent fashion. Alloantigen- induced proliferation was also potently suppressed when evaluated in a mixed lymphocyte culture assay. Tf-Ga affected a significant reduction in the density of IL-2 receptors on activated T cells and a slight reduction in the number of CD3+/CD25+ T cells in PHA-stimulated cultures. Neither secretion of interleukin-2 (IL-2) nor the induction of IL-2-stimulated lymphokine-activated killer activity, however, was inhibited by Tf-Ga. Tf-Ga produced significant upregulation of the transferrin receptor (CD71) in T cells as determined by flow cytometric analysis and northern blot assay, but did not affect the percentage of CD3+/ CD71+ T cells after mitogen stimulation. To assess the in vivo effects of gallium on alloreactive T cells, we evaluated the immunosuppressive effect of gallium in a murine model of graft-versus- host disease (GVHD). Administration of gallium significantly prolonged survival in mice undergoing severe GVHD, suggesting that gallium can ameliorate GVH reactivity. Collectively, these data demonstrate that, at clinically achievable concentrations, Tf-Ga potently inhibits T-cell activation and that this immunosuppressive property of gallium may be of adjunctive therapeutic value in the management of disorders characterized by the presence of autoreactive or alloreactive T-cell populations. 相似文献
86.
87.
88.
Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL 总被引:1,自引:1,他引:1
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states. 相似文献
89.
Ronan Thibault Anne-Marie Makhlouf Aurélien Mulliez M. Cristina Gonzalez Gintautas Kekstas Nada Rotovnik Kozjek Jean-Charles Preiser Isabel Ceniceros Rozalen Sylvain Dadet Zeljko Krznaric Kinga Kupczyk Fabienne Tamion Noël Cano Claude Pichard Phase Angle Project Investigators 《Intensive care medicine》2016,42(9):1445-1453
Purpose
Phase angle as measured by bioelectrical impedance analysis reflects fat-free mass. Fat-free mass loss relates to worse prognosis in chronic diseases. Primary aim of this study was: to determine the association between fat-free mass at intensive care unit admission and 28-day mortality.Methods
Ten centres in nine countries participated in this multicentre prospective observational study. The inclusion criteria were age >18 years; expected length of stay >48 h; absence of pacemaker, heart defibrillator implant, pregnancy and lactation. Fat-free mass was assessed by measurement of the 50-kHz phase angle at admission. The primary endpoint was 28-day mortality. The area under the receiver operating characteristic curve (AUC) was used to assess prediction of 28-day mortality by fat-free mass at ICU admission. The variables associated with 28-day mortality were analysed by means of multivariable logistic regression.Results
Of the 3605 patients screened, 931 were analysed: age 61 ± 16 years, male 60 %, APACHE II 19 ± 9, body mass index 26 ± 6, day 1 phase angle 4.5° ± 1.9°. Day 1 phase angle was lower in patients who eventually died than in survivors (4.1° ± 2.0° vs. 4.6° ± 1.8°, P = 0.001). The day 1 phase angle AUC for 28-day mortality was 0.63 [0.58–0.67]. In multivariable analysis, the following were independently associated with 28-day mortality: age (adjusted odds ratio (aOR) 1.014 [95 % confidence interval 1.002–1.027], P = 0.03), day 1 phase angle (aOR 0.86 [0.78–0.96], P = 0.008), APACHE II (aOR 1.08 [1.06–1.11], P < 0.001), surgical patient (aOR 0.51 [0.33–0.79], P = 0.002), and admission for other diagnosis (aOR 0.39 [0.21–0.72], P = 0.003). A multivariable combined score improved the predictability of 28-day mortality: AUC = 0.79 [0.75–0.82].Conclusion
Low fat-free mass at ICU admission is associated with 28-day mortality. A combined score improves mortality predictability. Trial registration: NCT01907347 (http://www.clinicaltrials.gov).90.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献