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Rectal endometrial stromal sarcoma arising in endometriosis   总被引:3,自引:0,他引:3  
PURPOSE: Endometriosis of the rectovaginal septum can harbor different types of secondary tumors that may involve the rectal wall and protrude into its lumen, thus making diagnosis difficult. Extrauterine low-grade endometrial stromal sarcoma may rarely arise in endometriosis. The purpose of this article was to present the third case of this association. METHOD: This was a clinicopathologic study. RESULTS: A 42-year-old female presented with abdominal pain and fever. Laparotomy revealed a large pelvic mass involving the rectovaginal septum and the colonic wall and which protruded into the lumen forming endoluminal polypoid masses. Concomitant peritoneal nodules and a metastatic paracolic lymph node were also found. Histopathologically, primary endometriotic foci were found in close relationship with an endometrial stromal sarcoma which invaded the rectal wall. The female genital tract had no endometriotic lesions. The patient was treated by surgery and subsequent chemotherapy and was alive and well 20 months later. CONCLUSIONS: Endometriosis and its possible malignant changes should be taken into account in the differential endoscopic diagnosis of rectal masses in females.  相似文献   
74.
Pneumatics is one of the few actuation principles that can be used in an MR environment, since it can produce high forces without affecting imaging quality. However, pneumatic control is challenging, due to the air high compliance and cylinders non-linearities. Furthermore, the system’s properties may change for each subject. Here, we present novel control strategies that adapt to the subject’s individual anatomy and needs while performing accurate periodic gait-like movements with an MRI compatible pneumatically driven robot. In subject-passive mode, an iterative learning controller (ILC) was implemented to reduce the system’s periodic disturbances. To allow the subjects to intend the task by themselves, a zero-force controller minimized the interaction forces between subject and robot. To assist patients who may be too weak, an assist-as-needed controller that adapts the assistance based on online measurement of the subject’s performance was designed. The controllers were experimentally tested. The ILC successfully learned to reduce the variability and tracking errors. The zero-force controller allowed subjects to step in a transparent environment. The assist-as-needed controller adapted the assistance based on individual needs, while still challenged the subjects to perform the task. The presented controllers can provide accurate pneumatic control in MR environments to allow assessments of brain activation.  相似文献   
75.
Mosquito samples were collected from rural and urban communities in three selected major towns in Southwestern Nigeria to determine the impact of urbanization on the diversity and abundance of Anopheles species associated with malaria transmission in human habitations. A total of ten Anopheles species were identified in the rural communities, while eight Anopheles species were identified in the urban communities. Out of the ten Anopheles species identified, only four species, Anopheles gambiae (Giles), Anopheles funestus (Giles), Anopheles moucheti (Evans), and Anopheles nili (Theobald), were established to be vectors of malaria occurring in greater than 50 % of the rural communities. Only A. gambiae occurred in all the urban communities, while the other three major vectors occurred in not more than 20 % of the urban communities. Margalef's and Shannon–Wiener indices showed that diversity and species richness were higher in the rural compared to the urban. Comprehensive information on malaria vector abundance and diversity in rapidly changing communities is an important tool in planning and implementing successful vector control programs.  相似文献   
76.

Objective

To determine whether stratification of complexity models in congenital heart surgery (RACHS-1, Aristotle basic score and STS-EACTS mortality score) fit to our center and determine the best method of discriminating hospital mortality.

Methods

Surgical procedures in congenital heart diseases in patients under 18 years of age were allocated to the categories proposed by the stratification of complexity methods currently available. The outcome hospital mortality was calculated for each category from the three models. Statistical analysis was performed to verify whether the categories presented different mortalities. The discriminatory ability of the models was determined by calculating the area under the ROC curve and a comparison between the curves of the three models was performed.

Results

360 patients were allocated according to the three methods. There was a statistically significant difference between the mortality categories: RACHS-1 (1) - 1.3%, (2) - 11.4%, (3)-27.3%, (4) - 50 %, (P<0.001); Aristotle basic score (1) - 1.1%, (2) - 12.2%, (3) - 34%, (4) - 64.7%, (P<0.001); and STS-EACTS mortality score (1) - 5.5 %, (2) - 13.6%, (3) - 18.7%, (4) - 35.8%, (P<0.001). The three models had similar accuracy by calculating the area under the ROC curve: RACHS-1- 0.738; STS-EACTS-0.739; Aristotle- 0.766.

Conclusion

The three models of stratification of complexity currently available in the literature are useful with different mortalities between the proposed categories with similar discriminatory capacity for hospital mortality.  相似文献   
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Background  

Human herpesvirus 8 (HHV-8), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) are prevalent in Africa, but less common elsewhere and the modes of transmission are still subject to debate. Generally, they rarely cause disease in the immunocompetent host but are highly oncogenic when associated with immunosuppression. Although the high prevalence of HHV-8, CMV and EBV has been well documented in Africa, such data are sparse from Ghana.  相似文献   
80.
To determine the effects of left ventricular hypertrophy on eplcardlal activation of the human heart, Intraoperative eplcardlal mapping of 40 to 66 points was performed In 10 patients undergoing aortic valve replacement. Mean calculated left ventricular mass was 364 ± 98 g. All patients had normal left ventricular contraction. Earliest eplcardlal activation occurred In the anterior right ventricle In all patients. In 9 patients, it was the only eplcardlal breakthrough point. One patient had a single Inferior left ventricular breakthrough point. Eplcardlal activation spread from the right ventricle towards the left ventricle in both the anterior and inferior direction. Latest eplcardlal activation occurred at the base of the left ventricle In 9 patients and the base of the right ventricle In 1.When compared with patients with coronary artery disease, normal ventricular contraction, and no left ventricular hypertrophy, patients with hypertrophy had fewer left ventricular breakthrough points (p <0.001) and were more likely to have latest activation at the left ventricular base (p <0.001).We conclude that left ventricular hypertrophy Is associated with marked changes In the pattern of epicardlal activation. These changes may reflect delay In spread from endocardium due to the increased wall thickness.  相似文献   
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