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71.
Deficient IgA and IgG2 anti-pneumococcal antibody levels and response to vaccination in otitis prone children 总被引:5,自引:0,他引:5
Dhooge IJ van Kempen MJ Sanders LA Rijkers GT 《International journal of pediatric otorhinolaryngology》2002,64(2):133-141
OBJECTIVE: To evaluate the isotype and IgG subclass distribution of anti-pneumococcal antibodies and response to polysaccharide vaccination in otitis prone children. METHODS: IgG1, IgG2 and IgA antibodies to pneumococcal serotypes 3, 4, 6B, 9V, 14, 19F and 23F were determined in otitis prone children and in an age-matched healthy control population. Patients were immunized with a 23-valent pneumococcal polysaccharide vaccine. The antibody response was measured 4 weeks later. RESULTS: Geometric mean IgA and IgG2 antibody levels for all seven pneumococcal serotypes tested were significantly lower in otitis prone children than in the control population. After immunization, there was no significant increase in geometric mean IgG2 anti-serotype 6B, 19F and 23F pneumococcal polysaccharide (weak immunogenic), but also no increase for IgG2 anti-serotype 4 and 14. Post immunization IgG2 antibody titers for serotypes 6B, 9V and 19F even remained below titers of non-vaccinated controls. Nine out of 29 otitis prone children were colonized nasopharyngeally with Streptococcus pneumoniae during the time of vaccination; these children had an even more severely impaired systemic antibody response. CONCLUSIONS: Otitis prone children, while having normal IgG1 antibody levels, have low IgG2 and IgA anti-polysaccharide antibody levels and fail to respond in these subclasses upon vaccination with pneumococcal polysaccharide vaccine. 相似文献
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74.
Knife-edge configurations or non space-maintaining defects of the alveolar ridge limit the indications for implant-prosthetic rehabilitation. If ridge expansion is required, bone splitting and bone spreading techniques may be applied. Summers introduced a modified approach for ridge expansion by osteotome technique. The principles of this nonablative implant bed preparation technique are lateral and apical bone relocation and condensation. The peri-implant alveolar bone loss after use of the osteotome technique was evaluated radiographically with respect to the bone quality in 22 patients with 22 implants. Differences between the alveolar crest and the implant shoulder in radiographs obtained immediately after implant insertion, after the end of unloaded healing period and after different periods of functional loading were calculated. The osteotome technique was used in bone quality classes 2 and 3, respectively, according to the Lekholm and Zarb classification. Two implants failed. Significant differences were found between the bone levels after implant insertion and at the end of the healing period as well as after functional loading (P = 0.028). The bone quality was significantly correlated (r = - 0.505; P = 0.023) with the change of the peri-implant marginal bone height level 6 months after the implant installation. The present data indicate the importance of bone quality evaluation before application of the osteotome technique. 相似文献
75.
Trypan blue not toxic for retinal pigment epithelium in vitro 总被引:2,自引:0,他引:2
Stalmans P Van Aken EH Melles G Veckeneer M Feron EJ Stalmans I 《American journal of ophthalmology》2003,135(2):234-236
PURPOSE: To investigate whether trypan blue has a toxic effect on cultured retinal pigment epithelial (retinal pigment epithelium) cells. DESIGN: Experimental study with a direct live/dead cell staining technique using fluorescent dyes. METHODS: Cultured human retinal pigment epithelium cells were exposed for 5 minutes to various concentrations of trypan blue (0.06%, 0.15%, 0.30%), and cell viability was confocally measured. RESULTS: No increased cell death was found in cultures incubated in any of the trypan blue concentrations used. CONCLUSION: These findings indicate that a short exposure of trypan blue does not have a toxic effect on cultured retinal pigment epithelium cells. 相似文献
76.
Friehs I Cao-Danh H Stamm C Cowan DB McGowan FX del Nido PJ 《The Journal of thoracic and cardiovascular surgery》2003,126(1):263-271
OBJECTIVE: Glucose is an important substrate for energy production in the developing heart. Increased glucose uptake rate and metabolism during ischemia and reperfusion are closely linked to postischemic myocardial recovery. The initial rate-limiting step for glycolysis is the transport of glucose across the plasma membrane by glucose transporters (GLUT-1 and GLUT-4). We hypothesized that changes in GLUT-1 and GLUT-4 expression in developing hearts lead to age-dependent adaptive changes in glucose uptake capacity and influence tolerance to ischemia. METHODS: Western-immunoblotting was performed to determine GLUT-1 and GLUT-4 expression in myocardial tissue from 1, 2, and 3-week-old and adult rabbits. Glucose uptake rate was measured with (31)P-nuclear magnetic resonance spectroscopy using 2-deoxyglucose as substrate in isolated perfused hearts. Hearts from same age rabbits were perfused in the Langendorff mode with crystalloid buffer or buffer plus a GLUT-4 specific antibody in order to determine GLUT-4 mediated effects on myocardial protection. The hearts were subjected to 30 minutes of normothermic ischemia followed by reperfusion. Cardiac contractile function measurements were obtained pre- and postischemia. Tissue lactate accumulation was measured in all groups at end-ischemia CONCLUSIONS: Insulin-regulated glucose transporter (GLUT-4) expression in the heart increased gradually after birth reaching nearly adult levels by 3 weeks of age. Corresponding with the higher amount of GLUT-4 protein, improved recovery of postischemic contractile function was seen in older hearts in association with increased anaerobic glycolytic capacity. Interventions to accelerate postnatal GLUT-4 expression may improve ischemic tolerance in the neonatal heart. 相似文献
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78.
OBJECTIVE: The objective of this study was to establish the feasibility of ulnar nerve block under direct imaging. CASE REPORTS: Two patients undergoing surgery on the fifth digit or medial hand received ulnar nerve blocks in the mid-forearm (approximately 15 cm proximal to the styloid process of the ulna). Ultrasound imaging was used to identify the ulnar nerve in the forearm and guide local anesthetic infiltration. Both patients had successful blocks, including sensory anesthesia of the dorsomedial hand. CONCLUSIONS: Ultrasound guidance for ulnar nerve block in the forearm is a promising technique that includes block of the dorsal cutaneous branch. Anatomic and sonographic considerations are discussed. 相似文献
79.
Hollaus PH Pucher I Wilfing G Wurnig PN Pridun NS 《Interactive Cardiovascular and Thoracic Surgery》2003,2(2):206-209
Knowing preoperative fears in cancer patients should help us to overcome perioperative psychological problems. One hundred and three patients underwent a semistructured interview addressing the effect of preoperative information on disease and forthcoming operation, attitude towards operation, expectations for the postoperative time and family support. Evaluation was performed by three psychologists by qualitative structured content analysis according to Mayring. Interrater reliability was 85%. Only 42 patients (40.8%) were informed in detail about their diagnosis. Eighty-three patients (80.6%) considered the information given on their disease and the forthcoming operation as understandable, 57 patient (55.3%) experienced reduction of fear. Eighty-three patients (80.6%) showed a positive attitude to the operation, 21 (20.4%) expected an impairment of later life after operation although becoming healthy again. Diffuse fears were named in 47 cases (45.6%), 19 (18.4%) patients were afraid of metastases, 11 (10.7%) of postoperative death, 19 (18.4%) of pain, 11 (10.7%) of mutilation and 17 (16.5%) of surgical complications. Seventy-three patients (70.9%) had good family support, seven (6.8%) not. Of the support group 32 patients (31%) considered their relatives' empathy as onerous. Problems, that are self-evident to the attending staff may be insurmountable for the patients. If we succeed to overcome their most simple fears they can focus their energy on mastering the postoperative course. 相似文献
80.
Cognitive impairment in patients
with carotid artery occlusion and ipsilateral transient ischemic
attacks 总被引:3,自引:0,他引:3
Bakker FC Klijn CJ Jennekens-Schinkel A van der Tweel I Tulleken CA Kappelle LJ 《Journal of neurology》2003,250(11):1340-1347
Abstract.
Although transient ischemic attacks (TIAs) by definition
do not cause lasting neurological deficits, cognitive impairment
has been suggested in patients with carotid artery disease who
have suffered from a TIA. The purpose of our study was to assess
whether patients with carotid artery disease and TIAs are
cognitively impaired, to describe the frequency, nature and
severity of this impairment, and to search for associated
patient characteristics.Thirty-nine consecutive patients with carotid occlusion
and ipsilateral cerebral or retinal TIAs, and 46 healthy
controls underwent extensive neuropsychological assessment.
Performances were compared group-wise with analysis of variance.
In addition, the presence of cognitive impairment in the
individual patient was determined. Associations between illness
characteristics and cognitive impairment were explored with
regression analysis.Fifty-four percent of patients were cognitively impaired.
Cognitive deficits were non-specific in nature and mild in
severity. Impairment occurred also in patients with isolated
retinal symptoms and in those without visible ischemic brain
lesions on MRI. Neither the presence of any vascular risk
factor, the side of the symptomatic carotid occlusion, the uni-
or bilaterality of carotid occlusion, nor the number of cerebral
ischemic lesions were predictors of cognitive impairment.We conclude that about half of the patients with carotid
artery occlusion and ipsilateral TIAs are cognitively impaired.
The presence of cognitive deficits in patients with isolated
retinal symptoms and in those without cerebral ischemic lesions
on MRI argues against an exclusive role for structural brain
damage in the pathogenesis of these deficits. 相似文献