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991.

Background  

Computer-assisted navigation was recently introduced to aid the resection of musculoskeletal tumors. However, it has not always been possible to directly navigate the osteotomy with real-time manipulation of available surgical tools. Registration techniques vary, although most existing systems use some form of surface matching.  相似文献   
992.
Mutations in the adenomatous polyposis coli gene (APC) often cause both congenital hypertrophy of the retinal pigment epithelium (CHRPE) and familial adenomatous polyposis (FAP). To investigate the relationship between APC mutations, CHRPE and FAP, all FAP patients at the Prince of Wales Hospital, Hong Kong, were asked to participate in a study. Ten Chinese patients from 6 kindreds and their family members volunteered, along with 12 healthy control subjects selected among hospital visitors and staff. All were examined for dilated fundus by indirect ophthalmoscopy. Mutations in APC coding exons were detected by sequencing. In one FAP patient, a novel A insertion at codon 1023 was detected. Three previously reported mutations were detected in 6 FAP patients: a deletion of ACAAA at codon 1061, and 2 truncating point substitutions at codons 216 and 283. In 3 FAP patients, no APC mutation was found, suggesting that mutations in APC coding regions are not the sole cause of FAP or CHRPE. A total of 64 CHRPE lesions were found in FAP patients and some relatives with and without APC mutations. Contrary to most reports, APC mutations before exon 9 did cause CHRPE lesions, albeit relatively few.  相似文献   
993.
To evaluate the efficacy of reduced intensity conditioning (RIC) prior to allogeneic stem cell transplantation (alloSCT) in patients with acute myeloid leukemia (AML) in first complete remission (CR1), we retrospectively analyzed the outcome of 93 consecutive patients transplanted at our institution either following RIC (n = 37) or standard myeloablative conditioning (MAC) (n = 56) between 1999 and 2007. Projected overall survival (OS) or disease-free survival (DFS) for all patients at 1, 2, and 5 years was 78 or 70%, 65 or 57%, and 61 or 53% in the RIC group versus 73 or 70%, 68 or 62%, and 56 or 54% in the standard MAC group. In the subgroup of patients with an intermediate-risk karyotype projected OS at 1, 2, and 5 years was 86, 68, and 68% following RIC (n = 21) or 75, 69, and 66% following standard MAC (n = 36). Relapse or treatment-related mortality (TRM) was 15 or 17% (RIC group) and 26 or 14% (standard MAC group). Taken together, these data suggest that RIC-alloSCT may induce stable remissions in patients with AML transplanted in CR1. In particular, patients with an intermediate-risk karyotype ineligible to transplantation following standard MAC may benefit from RIC-alloSCT in CR1 at a low TRM.  相似文献   
994.
995.
Solid-cystic-papillary tumors (SCPTs) of the pancreas are rare. The clinicopathologic features and pathogenesis of these tumors have attracted a number of investigations, but the results remain unclear. We investigated the clinicopathologic data, immunohistochemical expression of the pan-endocrine markers, hormones, steroid receptors, and p53 overexpression in pancreatic SCPTs from eight Chinese patients (seven women, one man) collected over a 24-year period. They accounted for 2.5% of the primary pancreatic tumors. The tumors were seen in young women (mean age 27 years). They were large (mean size of resected tumor was 8.4 cm), benign, had solid and cystic areas, and were evenly distributed in the pancreas. The main differential diagnosis was pancreatic endocrine tumor. The tumors were negative for pan-endocrine markers, hormones, estrogen receptor, progesterone receptor, and p53. To date, 452 pancreatic SCPTs have been documented in the English literature. They occurred in patients of different ethnic groups, particularly in non-Caucasians. The tumors were frequently noted in young females. Uncommon cases of malignant pancreatic SCPTs were often found in older men and had indolent behavior. It was concluded that pancreatic SCPTs have distinct clinicopathologic characteristics. The present observations, together with a review of the literature suggests that overexpression of p53 or estrogen receptor is not important in the pathogenesis of pancreatic SCPTs.  相似文献   
996.
Background There is a need to assess neurobehavioral performance of children in developing countries using standardized developmental tools. Methods The Griffiths Mental Development Scales was evaluated in the Philippines by comparing the performance of 742 Filipino children longitudinally at 6, 12 and 24 months old to those of their British counterparts. Results The mean general and subquotient scores of Filipino children were all within average for age. Comparison with British children showed that except for performance subscales, Filipino children had significantly higher developmental subquotients at 6 months old. As the Filipino infants grew older, their developmental subquotients in all subscales were significantly lower, except for personal and social skills at 24 months old. The genetic predisposition as evidenced by modest maternal scores on the Wechsler Intelligence Scales and lack of familiarity with test materials are factors that may influence the developmental patterns of Filipino children. Conclusion Although the performance of the Filipino children in the Griffiths test were within average with age, their performance on developmental subquotients at later ages of 12 and 24 months were significantly lower than British children and may have been influenced by differences in ethnicity, cultural traditions and limited environmental resources.  相似文献   
997.
BACKGROUND: Microalbuminuria is a marker of systemic endothelial dysfunction. We hypothesize that peritoneal albumin excretion in peritoneal dialysis (PD) patients, which is conceptually analogous to microalbuminuria in non-uremic patients, can predict cardiovascular disease in new PD patients. METHOD: We studied peritoneal albumin excretion in 43 new PD patients. They were then followed prospectively for the development of cardiovascular events. All-cause mortality and duration of hospitalization for cardiovascular diseases were also recorded. RESULT: The average duration of follow-up was 26.5 +/- 17.6 months. During the follow-up period, 15 patients developed cardiovascular events. Event-free survival at 36 months was 81.4% and 53.6% for low (< 300 mg/L) and high (> 300 mg/L) peritoneal albumin excretion groups respectively (log rank test, p = 0.042). By Cox regression analysis, the only independent factors for event-free survival were diabetic status and peritoneal albumin excretion rate. For every 100 mg/L increase in peritoneal albumin excretion, the adjusted hazard ratio of developing a cardiovascular event was 1.83 [95% confidence interval (CI) 1.11 - 3.02, p = 0.018]. Actuarial patient survival at 36 months was 85.7% and 59.1% for low and high peritoneal albumin excretion groups respectively (log rank test, p = 0.10). After adjusting for the duration of follow-up for individual patients, the average duration of hospitalization was 9.1 +/- 16.2 and 21.7 +/- 25.7 days per year of follow-up for low and high peritoneal albumin excretion groups respectively (Mann-Whitney U test, p = 0.012). CONCLUSION: Although the sample size of our present study is small and does not have adequate statistical power, we conclude that peritoneal albumin excretion may be an important predictor of cardiovascular disease. Further studies are needed to examine the role of dialysate albumin excretion as a means of cardiovascular risk stratification in PD patients.  相似文献   
998.
The effects of a simple training programme on the spatial disorientation of an 80-year-old patient suffering from dementia are reported. The patient's ability to find particular locations on the ward improved clearly in response to the training sessions. This learning was not related to learning a particular route around the ward, as may have been the case in previous reports. The success of this programme in the psychogeriatric assessment unit encouraged staff in the old people's home to which the patient was transferred to adopt similar methods.  相似文献   
999.
Summary Fifty patients with inoperable adenocarcinoma of the lung were randomized in a prospective study to receive either standard doses or high doses of 5-fluorouracil, adriamycin, and mitomycin-C (FAM versus Hi-FAM). The response/stabilization rate was 32% for FAM and 34% for Hi-FAM (P>0.05), and the median survival was 27 weeks for FAM group and 24 weeks for Hi-FAM group (P>0.05). Myelotoxicity was mild in FAM, but moderate to severe in Hi-FAM. It is concluded that Hi-FAM did not yield a higher response rate or median survival compared with FAM, but caused significantly more severe myelotoxicity.  相似文献   
1000.
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