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1.
We report a successful endovascular stent-graft treatment of a patient with type A dissection with primary entry tear at the ascending aorta. Simultaneous coronary stenting was performed. A literature review was performed and the possible use of endovascular treatment for ascending aortic dissections is discussed.  相似文献   
2.
Falloposcopy in conjunction with laparoscopy: possibilities and limitations   总被引:1,自引:1,他引:1  
Falloposcopy is a transvaginal microendoscopic technique to explore the human Fallopian tube from the uterotubal ostium to the fimbrial end. Falloposcopy provides a unique possibility to visualize endotubal disease and may be used therapeutically for removal of debris and for cutting down filmy intraluminal adhesions. To assess the clinical performance of falloposcopy as part of an infertility investigation, a total of 43 women scheduled for laparoscopy as part of an investigation of infertility had a falloposcopy performed in conjunction with the laparoscopy. All women were investigated at Danderyd Hospital, Stockholm and Akademiska Hospital, Uppsala, during 1995 and 1996. Images from the endosalpinx were obtained in 26 of 43 women (60.5%). In 10 women (23.3%), it was possible to obtain images from both tubes. No images were of sufficient quality to describe the entire tubal mucosa in detail. Falloposcopy represents a unique tool for visualization of endotubal disease and may provide a valuable instrument for in-vivo exploration of tubal physiology. However, certain technical problems limit the usefulness of this method in routine clinical practice. These technical problems have to be solved before falloposcopy can achieve a central position in investigation and treatment of tubal disease.   相似文献   
3.
Interstitial chromosomal deletions at 22q11.2 and 7q11.23 are detected in the vast majority of patients affected by CATCH 22 syndromes and the Williams-Beuren syndrome, respectively. In a group of 15 Williams- Beuren patients, we have shown previously that a large number of 7q11.23 deletions occur in association with an interchromosomal rearrangement, indicative of an unequal crossing-over event between the two homologous chromosomes 7. In this study, we show that a similar mechanism also underlies the formation of the 22q11.2 deletions associated with CATCH 22. In eight out of 10 families with a proband affected by CATCH 22, we were able to show that a meiotic recombination had occurred at the critical deleted region based on segregation analysis of grandparental haplotypes. The incidences of crossovers observed between the closest informative markers, proximal and distal to the deletion, were compared with the expected recombination frequencies between the markers. A significant number of recombination events occur at the breakpoint of deletions in CATCH 22 patients (P = 2.99x10(-7)). The segregation analysis of haplotypes in three- generation families was also performed on an extended number of Williams-Beuren cases (22 cases in all). The statistically significant occurrence of meiotic crossovers (P = 4.45x10(-9)) further supports the previous findings. Thus, unequal meiotic crossover events appear to play a relevant role in the formation of the two interstitial deletions. The recurrence risk for healthy parents in cases where such meiotic recombinations can be demonstrated is probably negligible. Such a finding is in agreement with the predominantly sporadic occurrence of the 22q11.2 and 7q11. 23 deletions. No parent-of-origin bias was observed in the two groups of patients with regard to the origin of the deletion and to the occurrence of inter- versus intrachromosomal rearrangements.   相似文献   
4.
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.  相似文献   
5.
OBJECTIVE: To establish the adenosine deaminase (ADA) activity in women who had been pregnant with a child suffering from central nervous system (CNS) anomaly. METHODS: The study group comprised 68 women who had been pregnant with an affected child, and 68 controls matched for age, gestational age and body mass index. Maternal venous blood was collected for measurement of ADA levels. We defined the diagnostic sensitivity, specificity and area under receiver-operating characteristic curve for ADA. RESULTS: Plasma ADA activity was significantly higher in the study group (12.3 U/L, range 1.7-33.3) compared to the median value of 3.3 U/L (range 1.1-34.4) in normal pregnancies (P<0.05). The cut-off point of ADA >5.9 U/L was associated with the highest combination of specificity (58.8%) and sensitivity (86.8%). CONCLUSION: ADA activity in women who have conceived a fetus with CNS malformations was significantly higher than that in normal pregnant women.  相似文献   
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The purpose of this study was to investigate the diagnostic accuracy of low-dose helical computed tomography by comparing the number of nodules detected at low- and standard-dose CT. The prospective study included 25 patients who were referred to CT scan for the assessment of pulmonary metastases. All patients underwent CT examinations at both standard- (200 mA, 120 kV, collimation 5 mm, table feed 10 mm per rotation) and low-dose (50 mA, 120 kV, collimation 5 mm, table feed 10 mm per rotation). The number of nodules detected at each protocol was recorded. The size of the nodules was measured electronically and categorized as <3, 3–4.9, 5–6.9, 7–9.9, and ≥10 mm. Finally, the nodules detected at only standard- or low-dose CT were assessed for the underlying causes of discrepancy. In 25 patients, 533 nodules were detected at standard-dose, whereas 518 nodules were observed at low-dose CT. There were no statistically significant differences in the number of nodules detected at standard- or low-dose CT (p>0.05). Four hundred ninety-one (87.7%) nodules were detected at both standard- or low-dose CT, 42 (7.5%) nodules were observed only at standard-dose CT, and 27 (4.8%) nodules were seen only at low-dose CT. The sensitivity of low-dose CT was 92.5% for all nodules, 88.1% for nodules <5 mm, and 97.4% for nodules ≥5 mm. No significant image artifact interfering with nodule detection was observed at low-dose CT. The low-dose CT protocol used in this study provided images of adequate quality; thus, it can be used reliably in the detection or exclusion of pulmonary nodules. Electronic Publication  相似文献   
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