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Bone morphogenetic proteins (BMPs) are bone growth factors, which regulate bone formation during fetal development and bone repair after injury in postfetal life. Since 1992 BMP-7 has been produced by recombinant technique (rhBMP-7). Numerous animal models and clinical trials have shown that rhBMP-7 can induce de novo bone formation in segmental defects of bones and in cases of nonunion. Since 2001 rhBMP-7 has been approved for treatment of tibial nonunion in Europe. The effect of rhBMP-7 is comparable to the clinical and radiological results achieved with bone autografts. The problem of donor site morbidity (which occurs in up to 20% of all cases) is eliminated by the use of BMP-7. Long-term results and experience in clinical practice are not yet available. 相似文献
998.
The acquisition of new food allergy after orthotopic liver transplantation is now a well described phenomenon, mainly reported in children. The etiology of this phenomenon is at present unclear, but has been ascribed by some to tacrolimus treatment. Here we report a case of liver transplant acquired food allergy (LTAFA) in a child who received a split liver graft. The case is remarkable for the absence of new food allergy in the adult recipient of the same graft. This suggests that host-specific factors play an important role in the development of food allergy after liver transplantation, and emphasizes the predisposition that children have toward this phenomenon. Possible mechanisms underlying the development of food allergy after liver transplantation are discussed. In conclusion, tacrolimus treatment alone cannot account for LTAFA. Host factors such as the maturity of immune regulatory mechanisms are likely to play a critical role in the development of new food allergy after a liver transplant. 相似文献
999.
E. Stermer J. Bejar† I. Miselevich† O. Goldstein D. Keren A. Lavy J. H. Boss† D. Keren 《Colorectal disease》2005,7(4):345-349
BACKGROUND: Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths. PATIENTS AND METHODS: This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other. RESULTS: Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample. CONCLUSIONS: In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful. 相似文献
1000.
Surgeon perspectives on options for ventral abdominal wall hernia repair: results of a postal questionnaire 总被引:3,自引:0,他引:3
Background: Ventral abdominal wall hernias are a common cause of morbidity and mortality. Opinion varies as to appropriate management.
A recent consensus meeting on incisional hernia identified the need to standardise repair. On this background, a survey of
current practice was performed. Method: A questionnaire was sent to 101 practicing general surgeons within the West of Scotland. Incisional, epigastric and para-umbilical
defects were subdivided into defect size <2, 2–5 and >5 cm. The surgeons were asked to indicate the most appropriate repair
(suture, mayo or mesh) for each. The influence of reducibility on the decision to repair was also assessed. Results: Sixty-one of 101 questionnaires were returned valid giving a response rate of 60%. Suture repair was significantly more
likely to be used in all defects <2 cm (P<0.001). Mesh repair was significantly more likely to be recommended in all defects >5 cm (P<0.001). Of defects >5-cm, mesh was recommended for 90% of incisional hernia compared with 81% of epigastric and 76% of para-umbilical
hernia (P<0.001). There was no significant difference in choice of repair for defect size 2–5 cm with opinion divided between suture
and mesh. Irreducibility increased the likelihood of recommendation for repair. Conclusion: This survey shows a lack of consensus on the appropriate repair of ventral abdominal wall hernia amonge practicing consultant
general surgeons. This reflects the contrasting views within the current literature. 相似文献