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The use of therapeutic apheresis in very low weight patients is generally thought to have limitations, because of possible severe adverse reactions, potential risk related to the extracorporeal procedure, due to the low weight of the young patients. A careful therapeutic approach using appropriate precautions, and also introducing modifications to the standard procedure, can minimise the risk without compromising the efficacy of the plasmapheresis. The aim of the study was to evaluate apheresis tolerance and acceptability in children [Artif. Organs. 21 (1997) 1126] and infants [J. Clin. Apheresis 5 (1989) 21] with inherited lipid metabolism disorder, familial hypercholesterolemia (FH), primary hyperlipoproteinemia (lipoprotein phenotype I), and acute leukemia, weighing on average 20.55 kg. One thousand one hundred twenty three aphereses were completed. Three types of apheresis were performed: leukapheresis, plasma exchange, dextran sulphate cellulose (DSC) low density lipoprotein (LDL)-apheresis. Three different types of continuous flow systems were used. Technical adaptation depending on patients blood volume, body mass index, hematocrit, type of system used, permitted us to perform complete aphereses, obtaining a high degree of tolerance and acceptability of the treatment. The use of plasmapheresis is regarded to be an extreme therapeutic measure in children. However, when the need for such treatment is undebatable, plasmapheresis must be done. A well-trained and experienced team can overcome the technical difficulties in order to complete the procedures without complications. The most frequently observed adverse effects are vascular relative access insufficiency (2.0%), and mild hypotension (2.0%).  相似文献   
3.
The effects of zygomatic complex fracture on masseteric muscle force.   总被引:1,自引:0,他引:1  
The masseter muscle often has been implicated as a primary cause of postreduction displacement of the fractured zygomatic complex. However, this contention has never been proved. This study compared masseter muscle force in 10 male controls with that in 10 male patients who had sustained unilateral zygomaticomaxillary complex (ZMC) fractures. Calculation of muscle force was based on measured bite force, electromyogram, and radiographic determination of muscle vectors. It was found that the masseter muscle in patients with ZMC fractures developed significantly less force than masseter muscle in controls. Following fracture, the masseter force slowly increased, but at 4 weeks following surgery the majority of patients were still well below control levels. The results of this study cast uncertainty on the role of the masseter muscle in postreduction displacement of the fractured ZMC.  相似文献   
4.
Purpose: Conjunctival hyperemia has been reported as a frequent side effect of bimatoprost, a prostamide with efficacious ocular hypotensive action. To investigate the possible inflammatory basis of the hyperemia, we analysed, by means of light microscopy, the conjunctival specimens of patients who developed ocular hyperemia during bimatoprost therapy and who underwent cataract surgery. Methods: Patients were divided in two groups;  相似文献   
5.
This randomized clinical trial compared frequencies of exclusive breastfeeding and lactation-related problems during the first 30 days among 74 mothers who received a 30-minute counseling session on breastfeeding technique in the maternity ward, and 137 controls. The frequency of exclusive breastfeeding among mothers who had received intervention was similar to controls by 7 days (79.7% vs 82.5%, respectively) and 30 days (60.8% vs 53.3%). There was no difference between groups in the frequency of sore nipples at 7 and 30 days, in breast engorgement and mastitis, and in the quality of breastfeeding technique at 30 days. Therefore, a single intervention at maternity was not sufficient to improve breastfeeding technique, increase exclusive breastfeeding rates, and reduce the incidence of breastfeeding problems during the first month.  相似文献   
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The features of enamel hypoplasia in a small group of patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) are described. Using a recently developed method, the authors evaluated quantitatively the amount of defect in each tooth by measuring the width of the hypoplastic lesions and dividing the value by the crown height. They then assessed the degree of damage in each tooth type (from central incisors to second premolars) and patient. Canines were the most severely affected among maxillary and mandibular teeth, but all tooth types were involved. Analysing both the differences between patients and their age at the beginning of the defect, the authors observe that hypoparathyroidism is not responsible for the onset of enamel hypoplasia in APECED, although it may contribute to the damage.  相似文献   
8.
OBJECTIVES: The aim of the study was to analyze the behavior of oxidative stress and its interplay with CD40L, a protein that is implicated in atherosclerosis, in hypercholesterolemic children. BACKGROUND: Oxidative stress has been suggested to play a major role in premature atherosclerosis. METHODS: Forty-one children with hypercholesterolemia (mean age 9.28 +/- 0.5 years) and 40 children with normocholesterolemia (mean age 9.02 +/- 0.69 years) were matched for gender and age. Within each group, children were classified as having or not having a family history of cardiovascular disease. Serum levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, and plasma levels of soluble CD40L (sCD40L) were measured in each child. In a subgroup of children with high (n = 8) or normal (n = 8) levels of serum cholesterol, platelet p38 mitogen-activated protein (MAP) kinase phosphorylation, a protein involved in the activation of nicotinamide adenine dinucleotide phosphate oxidase, was determined. RESULTS: Children with hypercholesterolemia had higher values of 8-OHdG and sCD40L compared with control subjects (0.55 +/- 0.06 ng/ml vs. 0.21 +/- 0.02 ng/ml, p < 0.001 and 0.55 +/- 0.04 ng/ml vs. 0.19 +/- 0.03 ng/ml, p < 0.001, respectively). A significant correlation between 8-OHdG and sCD40L was observed in children with high (r = 0.676, p < 0.001) or normal (r = 0.878, p < 0.001) levels of cholesterol. Children with a family history of cardiovascular disease tended to have higher values of 8-OHdG and sCD40L, but the difference was not significant. Analysis of platelet p38 MAP kinase showed that it was phosphorylated more in children with hypercholesterolemia compared with control subjects (36.8 +/- 5.8 AU vs. 8.0 +/- 4.5 AU, p < 0.001 respectively). CONCLUSIONS: Children with hypercholesterolemia have an early increase of oxidative stress that may be responsible for up-regulation of CD40L and potentially predispose to premature atherosclerosis.  相似文献   
9.
The potential of immunotherapy with autologous virus-specific T cells to affect the course of feline immunodeficiency virus (FIV) infection was explored in a group of specific-pathogen-free cats infected with FIV a minimum of 10 months earlier. Popliteal lymph node cells were stimulated by cocultivation with UV-inactivated autologous fibroblasts infected with recombinant vaccinia viruses expressing either FIV gag or env gene products, followed by expansion in interleukin-2. One or two infusions of both Gag- and Env-stimulated cells resulted in a slow increase in FIV-specific gamma interferon-secreting T cells in the circulation of cats. In the same animals, viral set points fluctuated widely during the first 2 to 3 weeks after adoptive transfer and then returned to pretreatment levels. The preexisting viral quasispecies was also found to be modulated, whereas no novel viral variants were detected. Circulating CD4(+) counts underwent a dramatic decline early after treatment. CD4/CD8 ratios remained instead essentially unchanged and eventually improved in some animals. In contrast, a single infusion of Gag-stimulated cells alone produced no apparent modulations of infection.  相似文献   
10.
NK cells acquire the ability to recognize MHC class I molecules during development. Studies with Qa-1(b) tetramers (Qa-1 tetramers) showed that nearly all NK1.1(+) cells from newborn C57BL/6 mice express Qa-1-binding receptors. Cytotoxic activity of these cells is fully inhibited by Qa-1 ligands on target cells. In contrast, neither receptors for H-2K(b) nor H-2D(b) were observed on NK1.1(+) cells from newborn mice. After birth, frequencies of Qa-1 tetramer(+)/ NK1.1(+) cells gradually decrease as the number of Ly49(+) /NK1.1(+) cells increases. Cell transfer studies showed that Qa-1 tetramer(+) cells from newborn mice do not lose expression of Qa-1 receptors, but that they further acquire expression of Ly49 molecules. Acquisition of Qa-1-binding receptors appears largely independent of host MHC class I molecules, as observed in studies using beta2-microglobulin-deficient (beta2m(-/-)) mice as well as K(b)/ D(b-/-) and K(b)/D(b)/beta2m(-/-) mice. The present results suggest that Qa-1-binding receptors play an important role in the specificity of developing NK cells, and suggest that these cells rely mainly on inhibitory receptors specific for non-classical MHC class I molecules to maintain self tolerance during the first weeks of life.  相似文献   
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