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Primary malignant tumors of the small intestine are uncommon. The average annual incidence rate over a period of 30 years in Saskatchewan was 0.7 and 0.6 per 100,000 for male and females, respectively. The 209 patients who comprise the series represent 1.6% of the total number who had gastrointestinal cancers over the same period. The distribution of the tumors by site and histologic type is described. Both carcinoid and adenocarcinomatous tumors of the small intestine are associated with a high incidence of primary malignant neoplasms in other sites (17.0 and 20.3%, respectively). One patient with Peutz-Jeghers syndrome is of interest because of the malignant change which occurred in more than one of the small bowel polyps and because of consequent liver metastases. The reason for the poor prognosis in noncarcinoid small bowel malignant neoplasms is probably due to late diagnosis. The five-year disease-free survival in these tumors was 22.5%. Malignant carcinoids had a better overall five-year survival rate of 64%. For those confined to the bowel wall, the five-year survival rate was 73%, compared to 59% for those extending to nodes or metastasizing to distant organs. 相似文献
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CI Stefanadis CG Stratos SG Lambrou VK Bahl DV Cokkinos VA Voudris SG Foussas CP Tsioufis PK Toutouzas 《Canadian Metallurgical Quarterly》1998,32(4):1009-1016
OBJECTIVES: Our aim was to present the immediate and intermediate long-term results of the application of retrograde nontransseptal balloon mitral valvuloplasty (RNBMV) in four cooperating centers from Greece and India. BACKGROUND: RNBMV is a purely transarterial method of balloon valvuloplasty, developed with the aim to avoid complications associated with transseptal catheterization. Only single-center experience with RNBMV has been previously reported. METHODS: The procedure was attempted in 441 patients with symptomatic mitral stenosis (320 women, 121 men, mean age [+/-SD] 44+/-11 years, mean echocardiographic score [+/-SD] 7.7+/-2.0) from 1988 to 1996. Three hundred eighty-five patients with successful immediate outcome were followed clinically for a mean [+/-SD] of 3.5+/-1.9 (range, 0.5-9.1) years. RESULTS: A technically successful procedure was achieved in 388 (88%) cases. The echocardiographic score (p < 0.001), male gender (p=0.005), preprocedural mitral regurgitation (p=0.007) and previous surgical commissurotomy (p=0.029) were unfavorable predictors of immediate outcome. Complications included death (0.2%), severe mitral regurgitation (3.4%) and injury of the femoral artery (1.1%). Event-free (freedom from cardiac death, mitral valve surgery, repeat valvuloplasty and NYHA class > II symptoms) survival rates (+/-SEM) were 100%, 96.9+/-0.9%, 89.8+/-1.9% and 75.5+/-5.5% at 1, 2, 4 and 9 years, respectively. The echocardiographic score (p < 0.001), NYHA class (p=0.008) and postprocedural mitral valve area (p=0.009) were significant independent predictors of intermediate long-term outcome. CONCLUSIONS: Multicenter experience indicates that RNBMV is a safe and effective technique for the treatment of symptomatic mitral stenosis. As with the transseptal approach, patients with favorable mitral valve anatomy derive the greatest immediate and intermediate long-term benefit from this procedure. 相似文献
164.
Home-made protective eyeshields are described, for use during certain types of skull radiography. Measurements made during the examination of patients and with a phantom skull indicate that a ten-fold reduction in radiation dose may be achieved through their use during certain diagnostic procedures. 相似文献
165.
We recently demonstrated that net fluid uptake occurs in the capillary system of the inner medulla. To define the site of fluid uptake, the concentration of protein was determined in plasma from descending vasa recta at the base and tip of the exposed papilla in Munich-Wister rats. The vasa recta plasma-to-arterial plasma protein concentration ratio (VR/P) was 1.43 +/- 0.09 at the base and 1.66 +/- 0.09 at the tip. These results, which indicate fluid loss from the descending vasa recta, are difficult to explain on the basic of hydraulic and oncotic forces alone. The osmolality of the contents of descending vasa recta increased between base and tip (delta = 72 +/- 30 mosmol/kg H2O). If the increase in osmolality of plasma in descending vasa recta lags behind that of the adjacent medullary interstitium, a transcapillary osmotic driving force exists favoring water loss from descending vessels. It is concluded that fluid uptake by the inner medullary circulation occurs beyond descending vasa recta in interconnecting capillaries or ascending vasa recta. In our view the most likely interpretation of these results is that fluid movement across vasa recta in the inner medulla is influenced by three forces: those owing to transcapillary differences in osmotic, oncotic, and hydraulic pressures. 相似文献
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