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Piezo-electric extracorporeal lithotripsy with ultrasonographic detection is performed with the following material according to the following technique: 1) A mobile firing head connected to the lumbar region by a simple inflatable cushion filled with sterile water. At the centre of the firing head, a 5 MHz real time transducer is used to locate the stone. 320 piezo-electric elements, arranged around the transducer, can induce, when focussed, a pressure of about 900 bars at the focal point in vitro. The focus is 15 mm X 5 mm. The generators are electronic. 2) The technique requires: understanding of ultrasonography in order to precisely locate the stone which, when it is intrarenal, is only missed in 1% of cases in our experience. Stones of the iliac ureter are not visible. Treatment requires the patient's confidence so that, due to the quality of the piezo-electric wave, no anaesthesia is necessary. The firing time should be relatively long (45 min to 1 hr) in order to ensure good fragmentation. 26% of patients require retreatment. Secondary complications are rare (3% of endoscopic treatments). The technique is now proposed in 90% of cases without admission to hospital. The simplicity of the manipulation of the apparatus must not mask the fact that it is a technique which requires perfect mastery. Only urologists familiar with stone pathology and who are able to treat the complications of lithotripsy by endoscopy or by surgery should perform extracorporeal lithotripsy.  相似文献   
975.
The association of replacement estrogens with breast cancer   总被引:4,自引:0,他引:4  
This epidemiologic case-control study examined the relationship between replacement estrogen use and breast cancer risk in 2 population groups in Hawaii. No significant associations were observed when 161 Caucasian cases were compared with either their neighborhood controls (RR = 0.9; 95% Cl = 0.5-1.3) or their hospital controls (RR = 0.7; 95% Cl = 0.4 to 1.1) and when 183 Japanese cases were compared with either their neighborhood controls (RR = 1.1; 95% Cl = 0.7-1.6) or their hospital controls (RR = 1.0; 95% Cl = 0.6-1.4). The results indicate that the use of replacement estrogens cannot account for the large difference in breast cancer incidence between the 2 Hawaiian ethnic groups. However, further data analysis involving neighborhood controls was suggestive of a possible increase in breast cancer risk with estrogen use for certain sub-groups of women who are at high risk for the disease. These included estrogen users with a family history of breast cancer or a history of benign breast disease. These findings are in agreement with other studies which have used non-hospitalized controls. Because the numbers of cases in this study are not substantial, it is recommended that a large population-based case-control study be undertaken to clarify the relationship between breast cancer risk and replacement estrogen use, especially in sub-groups of women at high risk for the disease.  相似文献   
976.
Three patients with malignant lymphoma, two of T-cell type and the other probably also of T-cell type, had an interstitial deletion of the short arm of chromosome 6, del (6)(p21p23), in common in their lymphoma cells. These findings suggest that this new type of chromosome deletion may be a specific marker for T-cell lymphoma and may play an important role in the lymphomagenesis and the expression of the T-cell phenotype.  相似文献   
977.
HTLV-I seroprevalence in patients with malignancy   总被引:5,自引:0,他引:5  
Since many malignancies often occur in patients with smoldering type adult T-cell leukemia (ATL) (5 of 18 cases in this report), the relationship between HTLV-I (human T-cell leukemia virus type I) infection, which is closely associated with ATL, with other malignancies in an HTLV-I endemic area was examined. Among the 394 patients with malignancies and who had not had blood cell transfusions, 61 (15.5%) tested positive for HTLV-I antibody. The prevalence was significantly higher in males older than age 40 years and females of all ages compared to age- and sex-matched healthy individuals. The overall seroprevalence (26.1%) in 291 patients with malignancies and who had had blood cell transfusions was higher than that of those who had not had blood transfusions. There was no significant correlation between the site of malignancy and antibody prevalence. These results suggest the possibility that development of malignancy may contribute to expression of latent HTLV-I infection and that HTLV-I infection may contribute to the risk of other malignancies.  相似文献   
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