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Six polyvinyl chloride and six polyethylene angioplasty balloons were inflated six times each under laboratory conditions. Outside diameter of the balloons was measured on initial and final inflations; volume was measured by water displacement at each inflation. In addition, three balloons in either group were constricted with a silk suture around the midportion. Balloons were then intentionally ruptured and the rupture site recorded. The diameters of the polyvinyl chloride balloons increased over six inflations, while they remained relatively constant for the polyethylene balloons. Rupture sites were in the area of the balloon that had the greatest outside diameter, and the tears were longitudinal. 相似文献
119.
Ovarian metastases: computed tomographic appearances 总被引:4,自引:0,他引:4
Computed tomographic scans of 34 patients with ovarian metastases were reviewed to assess the radiographic appearances and to correlate these with the primary neoplasms. Primary neoplasms were located in the colon (20 patients), breast (six), stomach (five), small bowel (one), bladder (one), and Wilms tumor of the kidney (one). The radiographic appearance of the metastatic lesions could be described as predominantly cystic (14 lesions), mixed (12 lesions), or solid (seven lesions). There was one false-negative examination which showed no ovarian enlargement, although neoplastic deposits were found on the ovary at laparotomy. The cystic and mixed lesions tended to be larger in overall diameter than the solid. The metastases from gastric carcinoma appeared solid in four of five cases. The metastases from the other neoplasms had variable appearances simulating primary ovarian carcinoma. 相似文献
120.
Mid-trimester loss--appraisal of a screening protocol 总被引:1,自引:0,他引:1
The main causes for mid-trimester loss are known. There is likely to be
overlap with those of first trimester loss, but the proportions may be
different. We wished to perform an aetiological survey in a large
population of patients with a history of recurrent miscarriage, for
possible explanations for their second trimester miscarriages. Database
analysis of 636 patients attending a UK University Teaching Hospital
dedicated miscarriage clinic between 1991 and 1996 revealed a 25%
prevalence (n = 158) for second trimester miscarriage. Results from an
investigative screening protocol were positive in 50% of cases: 33% (n =
52) tested positive for antiphospholipid syndrome (APS); 8% (n = 13)
fulfilled strict criteria for cervical incompetence; there was a 4%
prevalence of uterine anomaly; 3% for infection (n = 5) and 2% of patients
(n = 3) proved to be hypothyroid. Importantly, dual pathology was found in
5% of patients with a history of second trimester miscarriage. As
idiopathic mid-trimester loss is a diagnosis by exclusion, a high index of
suspicion is required, as are modern diagnostic techniques.
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