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991.
Non-Hodgkin's lymphoma (NHL) is the second most prevalent malignancy in patients infected with HIV. Approximately 30,000 new cases of NHL are diagnosed annually, and individuals with immunodeficiencies have a greater likelihood than the general population of developing NHL. Moreover, individuals who are seropositive for HIV have a fourfold greater risk of acquiring NHL. Most of these individuals will manifest NHL as a high-grade B-cell lymphoma with extranodal presentation. Response to standard chemotherapy and/or irradiation occurs frequently. However, because of opportunistic infections, overall survival is approximately five months. The expert nurse's role in assessment and management of symptoms associated with infection and side effects of therapy is critical.  相似文献   
992.
BACKGROUND: In adults with hepatitis C virus (HCV) infection, the severity of liver disease may be influenced by the mode of transmission. The purpose of this study was to evaluate whether the mode of transmission affects liver injury and viral load in children with chronic HCV infection, independent of duration of infection and/or HCV genotype. METHODS: Thirty-nine anti-HCV (EIA-2) positive patients, were divided into three groups: group 1, children with a history of blood transfusion (n = 9; age, 13.3+/-1.3 years), group 2, children with hemophilia (n = 19; age, 11.6+/-0.8 years); and group 3, children with maternal-fetal transmitted disease (n = 10; age, 4.7+/-1.1 years). Serum alanine aminotransferase, HCV viral load, HCV genotype, and liver histology were assessed. RESULTS: Serum HCV viral load was higher in group 2 (4.27+/-1.0x10(6) copies/ml; p = 0.006) than in group 1 (0.73+/-0.3x10(6) copies/ml) and in group 3 (0.83+/-0.2x10(6) copies/ml). Conversely, group 2 had less severe liver injury compared with children of similar age in group 1 (p = 0.022). Despite a shorter duration of infection, group 3 had liver injury similar to that in group 1. Hepatitis C virus genotype did not influence the level of viremia or liver injury. CONCLUSIONS: Although children with hemophilia exhibited a high HCV viral load, liver histopathology was less severe than in children who had acquired HCV by blood transfusion or maternal-fetal transmission. These observations support the need to investigate the role of host immune response rather than the virus per se in the pathogenesis of HCV infection in children.  相似文献   
993.
Background. Obstructive jaundice is an uncommon but important clinical problem in children with cancer. Percutaneous transhepatic biliary drainage is widely used to relieve malignant biliary obstruction in adults, but its use in children has not been well described.¶Materials and methods. Six patients aged between 1 and 17 years underwent external or internal-external biliary drainage to relieve malignant obstructive jaundice. Biochemical, haematological and microbiological parameters were measured before the procedure and repeated 7–9 days later.¶Results. External or internal-external biliary drainage was technically successful in all patients. No patient developed clinically significant biliary sepsis. Asymptomatic duodenal perforation occurred in one patient with bulky duodenal tumour following conversion from external to internal-external drainage.¶Conclusions. External biliary drainage may be successfully performed in children with malignant obstructive jaundice.  相似文献   
994.
BACKGROUND: This study provides insight into the clinical behavior, diagnostic complexities, and long-term management of patients with hyperplastic perilobar nephroblastomatosis (HPLN). PROCEDURE: Fifty-two patients with HPLN with available long-term follow-up were retrospectively analyzed for pathologic, radiologic, and clinical features. RESULTS: The mean age at diagnosis was 16 months; the lesions were bilateral in 49 patients. Of 33 patients who initially underwent diagnostic biopsy and adjuvant chemotherapy, 18 (55%) developed Wilms tumor (WT) at a mean of 35 months from diagnosis. Of 16 patients whose initial therapy included nephrectomy and adjuvant therapy, three (19%) developed WT at a mean of 36 months from diagnosis. All three patients who underwent initial diagnostic biopsy and received no adjuvant therapy during their initial course developed WT 4, 4, and 10 months following diagnosis. 24/52 patients developed either a single (13 patients) or multiple (11 patients) WT throughout their course; 8/24 (33%) of WT were anaplastic. The time from initial diagnosis to the development of the last WT ranged from 13 to 116 months (mean 42 months). Three children with HPLN died of WT at 3, 5, and 6 years of age; 2/3 were anaplastic. CONCLUSIONS: HPLN is a self-limited, pre-neoplastic proliferative process associated with a high risk of developing WT. The accurate diagnosis and the choices of therapy during the often-complex course of HPLN depend on the availability and accurate interpretation of a combination of pathologic, radiologic, and clinical information. When such information is appropriately obtained, the long-term survival of patients with HPLN is excellent.  相似文献   
995.
BACKGROUND: Certain mother-child feeding patterns (MCFPs) may promote childhood obesity and/or disordered eating. OBJECTIVES: To assess the demographic correlates of MCFPs and to test whether differences in MCFPs are associated with child body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) z scores in a population-based study. DESIGN: A secondary analysis of the National Longitudinal Survey of Youth main and child cohorts was conducted on more than 1000 Hispanic, African American, and non-Hispanic/non-African American children, aged 3 to 6 years. The MCFPs were measured by means of 3 interview questions probing mother-allotted child food choice, child compliance during meals, and child obedience during meals. RESULTS: Mothers of non-Hispanic/non-African American children allotted greater food choice than mothers of African American or Hispanic children. Maternal BMI and other demographic measures were unrelated to MCFPs. The lowest levels of mother-allotted child food choice and child eating compliance were associated with reduced child BMI, with mean BMI z scores of -0.36 and -0.41, respectively. Effect sizes were small, however, and MCFPs did not discriminate children who were overweight or at risk for being overweight from children who were not (P>.05). CONCLUSIONS: Feeding strategies providing the least child food choice were associated with reduced child BMI. However, MCFPs did not relate to child overweight status.  相似文献   
996.
von Willebrand Factor (VWF) is important in platelet adhesion and shear-dependent platelet activation. We performed flow cytometric analyses of VWF binding to and activation of platelets from healthy neonates, children, and adults. Platelets from cord blood (n = 38; gestational age: 36-42 wk; birth weight: 2.4-5.1 kg), neonatal venous blood (n = 19; d 2-3 of life), children (n = 15; age: 1.5-16.3 y), and adults (n = 22; age: 18-55 y) were studied. Binding of VWF was assessed using an antihuman VWF polyclonal antibody and a FITC-conjugated secondary antibody. Platelet activation was determined by the expression of CD62P, CD63, CD41, CD42b, activated GPIIb/IIIa (PAC-1), procoagulant surface (as reflected by annexin V binding), and microparticle formation. Although the mean percentage of VWF-positive platelets was not significantly higher in unstimulated platelets from 2- to 3-d-old neonates, their platelets were more activated than those from adults, and there was a positive correlation of VWF binding with platelet activation (CD62P: r = 0.74, p < 0.001; annexin V: r = 0.46, p < 0.05). In adults, after in vitro activation of platelets with thrombin and ADP, VWF binding to platelets increased and correlated significantly with CD62P expression (r = 0.71, p < 0.001). VWF binding to unstimulated neonatal platelets was, however, higher than that to in vitro-stimulated platelets from adults at the same level of expression of platelet activation markers. Further studies are required to assess the mechanism and significance of VWF binding to activated platelets in the neonatal period.  相似文献   
997.
Based on the results of the long-term CAMP clinical trial in childhood asthma, the benefits of continuous long-term use of inhaled glucocorticoid on asthma control are clear. Studies are in progress to evaluate whether early intervention with inhaled glucocorticoids can alter the natural history of asthma. Indicators are now being defined to identify the patient at risk for persistent asthma and thus to identify candidates for early intervention. Given the right medication and the patient profile, it may be possible to induce remission or even a cure. Patients with severe asthma have low pulmonary function that is difficult to improve, however. It will be important to recognize patients at risk for severe asthma and to intervene more effectively to prevent asthma progression. None of these advances will be possible without a comprehensive approach to asthma care including the ready access to health care. Although it seems that the rise in asthma mortality and morbidity has reached a plateau, there are significant racial and ethic disparities in asthma health care use and mortality. The goal should now be to strive for a reduction in asthma morbidity and mortality. A high proportion of asthma morbidity among inner-city children may be related to nonadherence; therefore targeting management approaches to improve adherence could prove effective in reducing morbidity. Recommendations have been made to integrate available resources in the United States to improve overall asthma outcomes for children.  相似文献   
998.
BACKGROUND: Several neurochemical abnormalities have been reported in bipolar disorder (BD), but the exact mechanisms that underlie its pathophysiology remain to be elucidated. Proton magnetic resonance spectroscopy (1HMRS) allows in vivo measurements of certain neurometabolites in the human brain. 1HMRS was used to investigate the dorsolateral prefrontal cortex (DLPFC) in bipolar subjects during a manic or mixed phase. N-acetyl-L-aspartate (NAA), choline-containing molecules (Cho), creatine plus phosphocreatine (Cr) and myoinositol (Ino) were measured. METHOD: Ten bipolar patients (nine manic, one mixed), diagnosed by a semi-structured clinical interview (SCID), and ten age- and gender-matched healthy volunteers were studied. Absolute neurometabolites levels were measured from two 8 cm3 voxels placed in left and right DLPFC using a short TE 1HMRS method at 1.5 T. T1- and T2-weighted anatomical magnetic resonance imaging was performed to exclude any neuroanatomical abnormality. RESULTS: No significant differences were found for NAA, Cho, Cr, Ino, NAA/Cr, Cho/Cr or Ino/Cr between patients and controls. Manic/mixed patients had significantly higher left-to-right myoinositol ratios in DLPFC (p = 0.044). CONCLUSIONS: Increased left-to-right myoinositol ratios in the DLPFC in bipolar patients during acute mania may represent a dysfunction in the phosphoinositide-signaling pathway. Longitudinal studies with larger samples of unmedicated patients assessing pre- and post-treatment times will be required for further clarification of the time course of these abnormalities and the relationship with treatment effects.  相似文献   
999.
Traumatic communications between the hepatic artery or its branches and the portal vein or its tributaries usually are clinically occult until the late sequelae of portal hypertension, such as esophageal and mesenteric varices, ascites, or congestive heart failure, become manifest. The authors describe the early diagnosis of such a lesion by computed tomography. The CT findings included a hepatic hematoma and, more significantly, diffuse thickening of the small and large bowel wall. This thickening represents vascular congestion of the bowel caused by acute portal hypertension prior to the development of decompressing portal collateral circuits. When this CT finding is not associated with other signs of intestinal ischemia or infarction, it should suggest portal hypertension and lead to arteriography for diagnosis and therapy of arterioportal fistula.  相似文献   
1000.
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