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21.
Respiratory syncytial virus-specific antibody responses in immunoglobulin A and E isotypes to the F and G proteins and to intact virus after natural infection 总被引:1,自引:1,他引:1
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R C Welliver M Sun S W Hildreth R Arumugham P L Ogra 《Journal of clinical microbiology》1989,27(2):295-299
We studied the antibody response to the fusion (F) and attachment (G) proteins of respiratory syncytial virus and to purified intact virus in the respiratory secretions of 29 infants and children. The goal of the study was to determine whether the immune response to either of the glycoproteins occurred predominantly in the immunoglobulin A (IgA) as opposed to the IgE isotype, which would indicate that one protein subunit would be a better candidate as a potential vaccine. Antibody responses were determined by using an enzyme-linked immunosorbent assay with purified F and G proteins and sucrose gradient-purified intact virus as targets. Infants and children were capable of developing an antibody response in both the IgA and IgE isotypes to each target antigen. The magnitude of the antibody response to the F protein was essentially similar to that to the intact virus, while responses to the G protein were diminished in infants. A slightly more favorable ratio of IgA to IgE responses was observed against the F protein in comparison to the G protein. While neither protein subunit had the ideal characteristics of inducing an IgA response in the absence of an IgE response, the F protein seems to be a better candidate for use as a vaccine, on the basis of better IgA/IgE ratios. 相似文献
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23.
Thyroid tumors following thymus irradiation 总被引:3,自引:0,他引:3
R E Shore E Woodard N Hildreth P Dvoretsky L Hempelmann B Pasternack 《Journal of the National Cancer Institute》1985,74(6):1177-1184
About 2,650 persons who received X-ray treatment for purported enlarged thymuses in infancy and 4,800 sibling controls have been followed by mail questionnaire for an average of 29 years to observe their incidence of thyroid tumors. The follow-up rate in the latest survey was 88% in both groups. The radiation doses to the thyroid gland ranged from 5 to over 1,000 rad, with 62% receiving less than 50 rad. To date 30 thyroid cancers and 59 benign thyroid adenomas have been detected in the irradiated group, as compared with 1 thyroid cancer and 8 adenomas in the control group. The relative risks in the irradiated group were about 45 for thyroid cancer and 15 for benign thyroid adenomas. The dose-response curve for thyroid cancer was essentially linear, although a linear-quadratic curve could not be ruled out. For thyroid adenomas the risk per rad was somewhat greater at lower doses than at high doses. For both thyroid cancers and adenomas the absolute excess risk per rad was two to three times as great in females as males. Within the limitations imposed by the treatment regimens and the sample size, there was no indication of a "sparing" effect due to dose fractionation for either thyroid cancers or adenomas. There was an excess risk for both malignant and benign thyroid tumors for at least 40 years post irradiation. For thyroid cancer the radiogenic risk appeared to be additive with respect to time, rather than the age-specific natural rates of cancer being multiplied. 相似文献
24.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
25.
Fordyce AM Lalani Z Songra AK Hildreth AJ Carton AT Hawkesford JE 《The British journal of oral & maxillofacial surgery》1999,37(1):52-57
We undertook a retrospective study of all isolated mandibular fractures which had required active management over a 1-year period at the Maxillofacial Unit at Newcastle General Hospital. Patients with single or multiple fractures of the mandible were included in the study, if there were other simultaneous fractures of the facial skeleton, those patients were excluded. All case notes and radiographs were reviewed by a single operator. A total of 202 cases of fractured mandible were identified of which 115 fulfilled the selection criteria of: isolated fracture, no previous facial fracture, treatment by open reduction and internal fixation using titanium osteosynthesis miniplates, and all case notes and radiographs available to study. Sixty-six patients had their fractures reduced manually to obtain anatomical reduction without the use of peroperative intermaxillary fixation (IMF). Forty-nine were treated conventionally using peroperative IMF. The two groups were broadly similar in severity and type of fracture, and the method of reduction seemed to be decided by the operator according to their preference. IMF was not used routinely postoperatively. Overall there were significantly fewer occlusal discrepancies in the early postoperative period in those patients treated by anatomical reduction (6/66 compared with 16/49, P = 0.002) but there was no difference in the final outcome of the occlusion between the two methods of reduction. Avoidance of the use of peroperative IMF is more economical in time and cost, is safer for the operator, and more comfortable for the patient. As this technique produces comparable results in the long term with fewer early complications, we conclude that IMF is not usually necessary to reduce fractures confined to the mandibular bone. 相似文献
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27.
Marrow regeneration after mechanical depletion 总被引:1,自引:0,他引:1
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration. 相似文献
28.
29.
Acute injuries of the distal radioulnar joint 总被引:1,自引:0,他引:1
Distal radioulnar joint injuries can occur in isolation or in association with distal radius fractures, Galeazzi fractures, Essex-Lopresti injuries, and both-bone forearm fractures. The authors have classified DRUJ/TFCC injuries into stable, partially unstable (subluxation), and unstable (dislocation) patterns based on the injured structures and clinical findings. Clinical findings and plain radiographs are usually sufficient to diagnose the lesion, but axial CT scans are pathognomonic. Diagnostic arthroscopy is the next test of choice to visualize stable and partially unstable lesions. Stable injuries of the DRUJ/TFCC unresponsive to conservative measures require arthroscopic debridement of the TFCC tear, along with ulnar shortening if there is ulnar-positive variance. Partially unstable injuries, on the other hand, are treated with direct arthroscopic or open repair of the TFCC tear, once again, along with ulnar shortening if ulnar-positive variance is present. Unstable injuries include simple and complex DRUJ dislocations. A simple DRUJ dislocation is easily reducible but may be stable or unstable. In complex dislocation, reduction is not possible because there is soft tissue interposition or a significant tear. After the associated injury is dealt with, treatment for complex injuries requires exploration of the DRUJ, extraction of the interposed tissue, repair of the soft tissues, and open reduction and internal fixation of the ulnar styloid fracture (if present and displaced). The early recognition and appropriate treatment of an acute DRUJ injury are critical to avoid progression to a chronic DRUJ disorder, the treatment of which is much more difficult and much less satisfying. 相似文献
30.
JE McMICHAEL 《Journal of paediatrics and child health》1997,33(1):1-3
An understanding of the neurodevelopmental outcome of long-term survivors of neonatal intensive care is essential for the informed management of preterm or high risk infants. This annotation looks at the current status of neonatal follow-up services in Australasia and highlights problems in the collection and interpretation of data. It suggests that we should work towards achieving a consensus on standard definitions and test regimes and on national data collection. 相似文献