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排序方式: 共有538条查询结果,搜索用时 10 毫秒
71.
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
72.
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
73.
Stephen Levinson MD Mohan Bhasker MD Thomas R. Gibson PhD Robert Morin MD Dr. William J. Snape Jr MD 《Digestive diseases and sciences》1985,30(1):33-39
Eating a 1000-kcal mixed meal stimulates an increase in distal colonic motility. Fat is the dietary component which is the major stimulant of colonic spike activity. In this study the colonic spike activity increased similarly after the mixed meal [19.1±2.4 spike potentials (SP)/30 min] and after the fat meal (19.4±5.4 SP/30 min). Fat stimulated a concentration-dependent increase in colonic motility only when in contact with the gastroduodenal mucosa. Intravenous administration of Liposyn (100 kcal/hr) did not stimulate an increase in colonic spike activity (3.3±1.3 SP/30 min) despite greater increase in plasma total fatty acid levels than after the oral ingestion of fat. In contrast both the oral ingestion and the intravenous administration of an amino acid mixture (Aminosyn) inhibited the gastrocolonic response after the 1000-kcal mixed meal. Thus, these studies demonstrate: (1) fat stimulates colonic motility only through direct mucosal contact, and (2) a mixture of amino acid inhibits colonic motility through either mucosal contact or by circulating in the plasma. The exact neurohumoral mechanisms involved in both of these effects is unknown at present. 相似文献
74.
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
75.
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
76.
77.
S Caserío C Gallego P Martin MT Moral CR Pallás A Galindo 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(10):1571-1577
Aim: To analyse the main prenatal and postnatal features of congenital chylothorax (CC), and the outcome including mid‐term follow‐up. Methods: We searched our databases for CC diagnosed between 1990 and 2006. Data of 29 cases were retrieved and analysed. Follow‐up until 3 years of age was available for all patients. Results: Most patients were diagnosed prenatally (94%) and most cases were complicated by foetal hydrops (66.7%). The overall survival rate at 3 years was 56%. A significantly poorer outcome was observed when foetal hydrops, preterm birth < 34 weeks, large effusions and/or early‐onset pneumothorax were present. An important but not significant improvement in the survival rate was observed through the study period; while in 1990–1998, the survival rate was 41.7%, from 1999 to 2006 it was 66.7% (p = 0.19). In the mid‐term follow‐up, we did not observe any recurrence of CC and most infants remain asymptomatic. However, 27% of survivors were diagnosed as having asthma in early infancy. Conclusion: CC still carries a significant risk of perinatal mortality. However, continuous advances in foetal and neonatal medicine are improving the prognosis of these patients, and nowadays most of them are likely to survive. Beyond the neonatal period, most survivors have an uneventful outcome. 相似文献
78.
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
79.
Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods. 相似文献
80.
Digital and conventional chest images: observer performance with Film Digital Radiography System 总被引:5,自引:0,他引:5
The Film Digital Radiography System (FilmDRS) is a device with a laser optical film digitizer, 2,000 X 2,000 X 12-bit memory, and a 1,000-line video display. To evaluate the adequacy of this device for general radiography of the chest, four readers independently analyzed both radiographs and the corresponding video display of the digitized chest images of 150 patients, consisting of 100 images of abnormalities and 50 normal images. The overall results indicate equal sensitivity for the two systems. The FilmDRS, with interactive windowing, proved superior in the detection of hilar and mediastinal disease. X-ray film was superior in allowing detection of hyperlucent states. There was equivalent sensitivity for other disease categories. Superior specificity was achieved with conventional radiographs. 相似文献