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21.
OBJECTIVE: We sought to reintroduce a historical procedure-intracapsular tonsillar reduction (partial tonsillectomy or tonsillotomy)-for tonsillar hypertrophy causing obstructive sleep disordered breathing (OSDB) in children, as well as to determine whether partial tonsillectomy, compared with conventional (total) tonsillectomy when performed by more than one surgeon, is equally effective for the relief of OSDB while resulting in less pain and more rapid recovery. STUDY DESIGN: We conducted a retrospective case series at a tertiary children's hospital. The charts of children who underwent partial tonsillectomy and total tonsillectomy (1998 through 2002) for postoperative complications were reviewed. The caregivers were surveyed to assess postoperative pain, rapidity of recovery, and effectiveness of surgery for relieving symptoms of OSDB. RESULTS: Two hundred forty-three children underwent partial tonsillectomy and 107 children underwent total tonsillectomy. There were no significant differences in immediate and delayed complications between the groups. Both operations were equally effective in relieving OSDB. Children who had partial tonsillectomy had significantly less postoperative pain and significantly more rapid recovery. CONCLUSION: Intracapsular tonsillar reduction with an endoscopic microdebrider relieves OSDB as effectively as conventional tonsillectomy, but results in less postoperative pain and a more rapid recovery.  相似文献   
22.
Campath-1H has been used successfully for induction and has resulted in a low rate of acute cellular rejection (ACR) in renal transplantation in combination with various postoperative immunosuppression regimens. This study was undertaken to investigate the extent of monocyte involvement in ACR, with or without Campath-1H induction. We found that monocytes represented the majority of inflammatory cells in grades Ib or higher ACR, but not with Ia type of ACR, regardless of the status of Campath-1H induction. Cases of ACR, following Campath-1H induction, appear to demonstrate a 'pure form' of monocytic ACR, whereas monocytes were mixed with many other types of inflammatory cells in the cases of ACR in the absence of Campath-1H induction. In addition with Campath-1H induction, the cases of monocyte-predominant ACR were found to uniformly exhibit a good response to corticosteroid treatment. We conclude that monocyte-predominate ACR may represent a severe form of rejection, with or without Campath-1H treatment.  相似文献   
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A method for monitoring formation of latex particle pairs by chemiluminescence is described. Molecular oxygen is excited by a photosensitizer and an antenna dye that are dissolved in one of the particles. 1 delta gO2 diffuses to the second particle and initiates a high quantum yield chemiluminescent reaction of an olefin that is dissolved in it. The efficiency of 1 delta gO2 transfer between particles is approximately 3.5%. The technique permits real-time measurement of particle binding kinetics. Second-order rate constants increase with the number of receptor binding sites on the particles and approach diffusion control. By using antibody-coated particles, a homogeneous immunoassay capable of detecting approximately 4 amol of thyroid-stimulating hormone in 12 min was demonstrated. Single molecules of analyte produce particle heterodimers that are detected even when no larger aggregates are formed.  相似文献   
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Background: The C‐100 colour vision test has been shown to have a high validity for diagnosing the type of red‐green colour vision defect, however, there is little information on the repeatability of the test. This study examines the repeatability of the C‐100 in classifying the colour vision defect as either protan or deutan. Methods: The C‐100 was administered on two occasions to 58 subjects with congenital red‐green colour vision defects: The sessions were separated by a minimum period of 10 days. Results: The repeatability of the C‐100 was high with a kappa coefficient of agreement for diagnosis of 0.96. The few discrepancies were misclassifying protans as deutans. Conclusion: The C‐100 is a highly repeatable test in terms of separating protans from deutans. However, if a discrepancy occurs, it is more likely to be a protan misclassified as a deutan rather than vice versa.  相似文献   
27.
Defects in immune reconstitution after hematopoietic stem cell transplantation confer extreme infection risk on to the transplant recipient. Perturbations in adaptive immune reconstitution have been well characterized, yet defects in reconstituted innate cellular-mediated immunity remain largely unstudied. Recovery in innate effector cells was defined by using an established murine model of autologous bone marrow transplantation. Cytokine induction after cell culture and systemic stimulation with pathogen-associated molecular patterns was also measured for control, transplant-recipient, and irradiated-only animals. Early reconstitution (7 to 14 days) of donor-derived macrophages, dendritic cells, and polymorphonuclear cells was associated with recovery in interleukin (IL)-12p70 and IL-6 production. Later reconstitution (21 days) of natural killer cells was associated with interferon (IFN)-gamma recovery. Hence, splenocyte innate cellular-mediated immunity recovered to normal levels in cellularity and IL-12p70, IFN-gamma, and IFN-alpha production by 21 days after transplantation. In contrast, levels of systemic cytokine production from transplant-recipient and irradiated-only animals were preserved despite incomplete or absent hematopoietic reconstitution. These results suggest that innate immune responses to systemic inflammatory challenges are largely intact after autologous bone marrow transplantation, whereas local innate cellular-mediated immunity within reconstituting lymphoid organs may be impaired. The disparate effects of autologous hematopoietic stem cell transplantation on host immune function may translate to differences in susceptibility to local versus systemic infectious challenges.  相似文献   
28.
The cause of fetal distress and neonatal respiratory distress (RD) in association with meconium-stained liquor is not always clear. To clarify this, a prospective study was undertaken in a tertiary referral maternity hospital for 1 year. In all infants born after meconium-stained liquor who developed RD, evidence was sought for 1) fetal distress (from the cardiotocograph (CTG), the cord blood pH, the Apgar score and the asphyxial complications in the neonate) 2) causes of fetal distress (including maternal risk factors, fetal infection and fetal malnutrition) 3) causes of respiratory distress (including meconium aspiration syndrome (MAS), persistent pulmonary hypertension of the newborn (PPHN) and infection). Of 4,026 livebirths, 717 (17.8%) had meconium-stained liquor and 44 term and 5 preterm infants developed RD. In the 44 term infants, there was frequent evidence of fetal distress possibly caused by previously unrecognized factors such as fetal malnutrition with reduced neonatal skinfold thickness in 35% triceps and 41% subscapular measurements, and histological chorioamnionitis (CA) in 74%. The cause for respiratory distress was identified in only 48% of infants, and included clinical evidence of PPHN (41%), MAS (16%) and infection (2%). However in preterm infants, 80% had definite or suspected infection. The findings indicate that fetal distress is common in infants who develop respiratory distress after meconium-stained liquor. A role for histological CA and reduced nutrition in the fetus, as factors contributing to the vulnerability of the term infant to intrapartum fetal distress, is suggested.  相似文献   
29.
The purpose of this study was to assess the effectiveness and safety of Gadolite Oral Suspension as a gastrointestinal (GI) contrast agent for MRI in a phase II and two phase III multicenter clinical trials. Gadolite was administered to 306 patients with known or suspected abdominal and/or pelvic disease. MRI with T1- and T2-weighted sequences was performed before and after ingestion. Efficacy was evaluated by having two masked readers rate the certainty of their MR diagnosis (0 = uncertain, 1 = probable, 2 = definite) on randomly presented pre- and post-Gadolite Oral Suspension enhanced images. Principal investigators also evaluated the images and established the final diagnosis. Vital signs, clinical chemistries, and adverse events were documented. Blood and urine samples were analyzed for gadolinium content to determine whether Gadolite Oral Suspension was absorbed systemically. Certainty in MR diagnosis increased significantly (P < .001) for both blinded readers between pre- and post-Gadolite images (.49–1.18 for reader 1; .46–1.53 for reader 2). Sensitivity, specificity, and accuracy also increased for both masked readers. No gadolinium was detected in blood or urine samples. There were no serious adverse events and no apparent drug-related trends in mean vital signs or laboratory values. Gadolite is a highly effective, safe, and well tolerated contrast agent for clinical use with MRI.  相似文献   
30.
A luminol-enhanced chemiluminescence (CL) assay was used to study the microbicidal potential of phagocytic cells and the opsonic properties of serum in renal transplant recipients. Thirty-four patients receiving maintenance immunosuppression with prednisone and either cyclosporine or azathioprine and 35 normal controls were studied. Polymorphonuclear leukocytes (PMN) and monocytes were stimulated at the Fc receptor with heat-aggregated IgG (HAIgG) or immunoglobulin-treated zymosan (ITZ), and at the C3b receptor with serum-treated zymosan. Serum opsonic activity was determined by incubating zymosan with normal or patient serum and stimulating the CL response of normal phagocytes. We found that the Fc and C3b-dependent CL of PMN, the C3b-dependent CL of monocytes, and the opsonic properties of serum were identical in transplant recipients and normal controls. In contrast, the Fc-dependent CL of monocytes in renal transplant patients was 3 times greater than normal when stimulated with either soluble (HAIgG) or particulate (ITZ) ligands. These data suggest that some components of the host immune system are not affected by maintenance immunosuppressive medication in renal transplant recipients. The mechanisms and significance of the increased Fc-receptor-dependent CL observed in monocytes of renal transplant patients remain to be determined.  相似文献   
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