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51.
The Aberdeen section scanner provides, in addition to conventional views, a display of the distribution of radioactivity in a tomographic section of the brain. This paper examined the value of this additional information. Scans of lesions confirmed pathologically or radiologically, along with normal and doubtful cases, were examined after a careful randomization procedure. During the course of the study each set of conventional views was examined twice, once without and once with a tomographic section view. In two out of 29 cases (7%) the lesion was diagnosed only with the aid of the tomographic section scan. Improved accuracy of diagnosis with the tomographic section view was significant at the 1% level or better.  相似文献   
52.
In the Netherlands, childhood leukaemia is recorded by the Dutch Childhood Leukaemia Study Group (DCLSG, set up in 1972) and by nine regional cancer registries which together form the Netherlands Cancer Registry (NCR, set up in 1989). The data files from the incidence years 1989-1992 of the two registries were linked in order to evaluate accuracy and completeness and to calculate and equalise the incidence rates for childhood leukaemia in The Netherlands. Unlinked records or records with disagreements (birth date, sex, type of leukaemia and incidence date) were checked by the DCLSG and by the regional cancer registries. The DCLSG recorded 431 cases of childhood leukaemia, while the NCR recorded 434 cases. After record linkage and review of the cases, it was concluded the 445 records should have been recorded as childhood leukaemia. The NCR had recorded 425 of the 445 correct cases (95.5%), but had missed 20 cases (4.5%). The DCLSG had recorded 431 of the 445 correct cases (96.9%) and had missed 14 cases (3.1%). In addition, the NCR had recorded 9 cases incorrectly as childhood leukaemia. Part of the disagreement was caused by differences in coding rules (definition of non-Hodgkin's lymphoma (NHL) and the myelodysplastic syndrome versus leukaemia). It could be concluded that the quality and completeness of the two registries was very high. Regular comparison of the recorded data will help to reveal the inherently problematic disagreement between definitions and coding.  相似文献   
53.
BACKGROUND: Transcatheter arterial chemoembolization (TACE) has been contra-indicated for the treatment of patients with hepatocellular carcinoma (HCC) and main portal vein (MPV) obstruction because of the potential risk of hepatic insufficiency resulting from ischemia after TACE. The current controlled study was undertaken to assess the safety, efficacy, and predictive factors of favorable response to TACE in patients with HCC and MPV obstruction with good hepatic function and adequate collateral circulation around the MPV. METHODS: Of a total of 47 patients, 31 were treated with TACE, and 16 who declined the procedures were untreated controls. Thirty-six patients (77%) had diffuse-type HCC and 11 (23%) had nodular-type HCC. During the first week after TACE immediate postprocedural complications were evaluated, and the development of hepatic insufficiency as a late complication was assessed at the end of the fourth week. The cumulative survival rate was estimated by the Kaplan-Meier method, and predictors of better prognosis were obtained by univariate and multivariate analyses. RESULTS: Although no patients showed clinical evidence of hepatic insufficiency as an immediate complication, transient fever and abdominal pain were common. Progressive hepatic insufficiency developed at the fourth week; however, there was no difference between the treated and untreated groups. The survival time of treated patients was statistically no longer than that of untreated patients. In the univariate analysis, tumor type and size, the pattern of iodized oil uptake in the tumor, and the presence of iodized oil uptake in the tumor thrombi at the MPV significantly influenced the prognosis. Tumor type, whether treated or not, was the most important prognostic factor patients with nodular-type HCC had significantly longer survival time (median, 11 months) than those with diffuse-type HCC (median, 4 months). Regarding the efficacy of TACE, there was no statistical difference in survival between treated and untreated diffuse-type HCC patients. In comparison, with nodular-type HCC it seemed that survival time was longer for TACE-treated patients (median, 30 months) than for untreated patients (median, 7 months). CONCLUSIONS: TACE may be a safe modality for the treatment of patients with HCC and MPV obstruction, provided that the patients have good hepatic function and collateral circulation around the MPV. However, TACE was not efficacious in the treatment of diffuse-type HCC. The authors recommend TACE for treating nodular-type HCC because of the potential benefit of prolonged survival.  相似文献   
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Dermatofibrosarcoma protuberans (DFSP) is a low-intermediate-grade cutaneous sarcoma that has a marked propensity for local recurrence after excision. The Bednar variant of this tumor is even less common and is distinguished histologically by the dispersal of melanin containing cells in an otherwise typical DFSP. Both are considered to be tumors of the third and forth decades of life, but both DFSP and the Bednar variant have been described in children. Until this report of a congenital Bednar tumor, only the DFSP has also been described in the neonate. The histopathology and surgical management of DFSP and Bednar tumors are outlined with emphasis on reported experience in the pediatric population. The surgical management of these lesions in children is based on numerous series in adults and the limited pediatric experience. The recommended treatment is wide excision with 3-cm margins of visibly uninvolved tissue and inclusion of superficial fascia.  相似文献   
58.
A case of an isolated frontal sinus fracture, reduced, fixed with miniplates and screws, and using the endoscopic technique, was presented. This case demonstrates the safety, efficacy, and economy of the endoscopic technique in properly selected cases that do not involve posterior table fractures or injury to the nasofrontal duct. The technique avoids the use of general anesthesia and the potential morbidities of coronal flaps.  相似文献   
59.
In conclusion, surgical myocardial revascularization has utilized diverse methods to increase blood flow to the starving myocardium. These methods initially used the microcirculation as the portal to reach myocytes until angiography showed that the obstructions were macrovascular. This resulted in a 30-year era of direct attack on the coronary blockages by coronary bypass. Surgical conduits unfortunately have longevity considerably less than that of native arteries and are limited in number. Alternative conduits, both biologic and prosthetic, have not yet proved to have the same clinical results as the ITA. More patients are living long enough to have the extensiveness of their disease exhaust conventional therapies. Newer therapy, restricted thus far to untreatables, revisits the microcirculation by making laser channels. These many innovative procedures have benefited hundreds of thousands of patients. They emerged from the probity and innovation of many individual surgeons.  相似文献   
60.
The formation of Maillard products is increased in the diabetes mellitus. These advanced glycated end products (AGEs) alter metabolic functions of macromolecules and increase free radical formation while decreasing free radical-scavenging enzyme activity. The elimination of AGEs is insured by the macrophage cells equipped with appropriate receptors (RAGE) and cleared by kidneys. The knowledge of these molecular mechanisms had allowed the emergence of biochemical analytes such as 3-deoxyglucosone, pentosidine, and carboxymethyl-lysine, as markers of the ris of micro- and macro-angiopathy, the main chronic complications of the diabetes mellitus.  相似文献   
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