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The presence of a fatty liver often complicates the interpretation of abdominal computed tomography (CT). Abnormalities in or adjacent to the liver, including dilated bile ducts, liver masses and subphrenic collections, may be masked by the fatty liver. Furthermore, normal structures may simulate pathological conditions. Five cases are presented to illustrate some of these diagnostic pitfalls.  相似文献   
94.
We evaluated the efficacy of recommended tuberculosis (TB) infection control measures by using a deterministic mathematical model for airborne contagion. We examined the percentage of purified protein derivative conversions under various exposure conditions, environmental controlstrategies, and respiratory protective devices. We conclude that environmental control cannot eliminate the risk for TB transmission during high-risk procedures; respiratory protective devices, and particularly high-efficiency particulate air masks, may provide nearly complete protection if used with air filtration or ultraviolet irradiation. Nevertheless, the efficiency of these control measures decreases as the infectivity of the source case increases. Therefore, administrative control measures (e.g., indentifying and isolating patients with infectious TB) are the most effective because they substantially reduce the rate of infection.  相似文献   
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Background  

Continuous intrathecal drug delivery has been shown in open studies to improve pain and quality of life in those with intractable back pain who have had spinal surgery. There is limited data on long term effects and and even less for patients with mechanical back pain without prior spinal surgery.  相似文献   
97.
A rare case of late intraneural metastasis of the brachial plexus from mammary carcinoma is reported. The lesion was strictly intraneural and had a latency of 29 years and the diagnosis was made incidentally in the course of surgery. The clinicopathological and diagnostic features of the tumor are discussed in the light of the accessible literature.  相似文献   
98.
A number of nonneoplastic glandular lesions of the uterine cervix may be misinterpreted as malignant. Familiarity with their histopathologic features is essential in their recognition and appropriate management. This discussion reviews the clinical and pathologic features of a variety of pseudoneoplastic glandular lesions of the uterine cervix, with an emphasis on those that have been recently described and those that one may encounter more commonly in practice. The entities that will be discussed include tunnel clusters, microglandular hyperplasia, mesonephric hyperplasia, endocervical glandular hyperplasia, and the Arias-Stella reaction.  相似文献   
99.
Fungal infections due to Candida species represent an important cause of nosocomial bloodstream infections. We report a large pseudo-outbreak of Candida guilliermondii fungemia that occurred in a university hospital in Brazil. C. guilliermondii was identified in 64 (43%) of the 149 blood samples drawn between June 2003 and July 2004. The samples were from patients in different wards of the hospital but concentrated in pediatric units. None of the patients had clinical signs of fungemia, and observational analysis revealed errors in the collection of blood samples. During the investigation of the pseudo-outbreak, C. guilliermondii was isolated from environmental surfaces and from the skin and nails of members of the nursing team. Through a subtyping analysis it was found that some of the nonpatient isolates were highly related to the patient isolates, and all the patient isolates were highly related. This is consistent with the hypothesis that the pseudo-outbreak was from a limited number of common sources. The adoption of intervention measures was effective in resolving the outbreak, supporting the hypothesis that the outbreak was due to poor techniques of drawing blood samples for culture.  相似文献   
100.
BACKGROUNDNeuroendocrine gastrointestinal tumors (NETs) are rare and have different natural behaviors. Surgery is the gold standard treatment for local disease while radiotherapy has been demonstrated to be ineffective. Poorly differentiated neuroendocrine carcinomas (NECs) represent only 5%-10% of digestive NETS. Due to aggressive growth and rapid metastatic diffusion, early diagnosis and a multidisciplinary approach are mandatory. The role of surgery and radiotherapy in this setting is still debated, and chemotherapy remains the treatment of choice.CASE SUMMARYA 42-year-old male with an ulcerated bleeding rectal lesion was diagnosed with a NEC G3 (Ki67 index > 90%) on May 2015 and initially treated with 3 cycles of first-line chemotherapy, but showed early local progressive disease at 3 mo and underwent sphincter-sparing open anterior low rectal resection. In September 2015, the first post-surgery total-body computed tomography (CT) scan showed an early pelvic disease relapse. Therefore, systemic chemotherapy with FOLFIRI was started and the patient obtained only a partial response. This was followed by pelvic radiotherapy (50 Gy). On April 2016, a CT scan and 18F-fluorodeoxyglucose positron emission tomography imaging showed a complete response (CR) of the pelvic lesion, but pathological abdominal inter-aortocaval lymph nodes were observed. Due to disease progression of abdominal malignant nodes, the patient received radiotherapy at 45 Gy, and finally obtained a CR. As of January 2021, the patient has no symptoms of relapse and no late toxicity after chemotherapy or radiotherapy.CONCLUSIONThis case demonstrates how a multimodal approach can be successful in obtaining long-term CR in metastatic sites in patients with high grade digestive NECs.  相似文献   
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