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Surface shield: device to reduce personnel radiation exposure   总被引:2,自引:0,他引:2  
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.  相似文献   
53.
This article reports six cases of litigants claiming neuropsychiatric impairment due to toxic mold exposure. In spite of recent growth in personal injury claims due to mold, numerous reviews of the literature have failed to find an association between environmental exposure to mold and neuropsychiatric and/or neuropsychological damage. We report data on six patients claiming harm, 4 of whom revealed a long history of somatization by history and psychological testing, and 2 of whom were shown to be malingering based on multiple indicators of non-credible performance. Of the 6 patients, only the 2 somatoform patients who were also depressed showed credible evidence of neuropsychological dysfunction. We review two other studies that have examined the link between mold exposure and cognitive impairment and discuss their limitations in view of the presenting behaviors of these 6 patients. Until the literature has established a credible link between mold and neuropsychiatric/neuropsychological impairment, jurists and clinicians must consider the ethics and potential harm of exposing somatoform patients to multiple unwarranted medical evaluations. Principles for forensic evaluations in this special population are reviewed.  相似文献   
54.
Sclerosing cholangitis: CT findings   总被引:5,自引:0,他引:5  
The value of computed tomography (CT) in the detection of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary systems was assessed by comparing CT scans of 20 cases of PSC with cholangiographic findings. In 16 of 19 cases of extrahepatic duct disease demonstrated with cholangiography, CT demonstrated abnormalities of the common hepatic duct, or bile duct, including duct stenosis, mural nodularity, duct dilatation, wall thickening, and mural enhancement. CT demonstrated intrahepatic disease in all 20 cases, including duct dilatation, duct stenosis, pruning, and beading. CT was superior to cholangiography in characterization of the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT demonstrated extrabiliary complications of PSC in 12 cases and superimposed cholangiocarcinoma in three cases. While cholangiography remains the standard for diagnosis and follow-up of PSC, CT can provide valuable information about the extent and complications of the disease.  相似文献   
55.
Abstract

Background/Objective: Few detailed studies have been performed among subjects with spinal cord injury (SCI) using whole body plethysmography for measurement of static lung volumes. Because abdominal gas volumes and respiratory patterns among subjects with varying Ieveis of SCI may differ significantly from able-bodied individuals, methodological concerns related to this technique could conceivably Iead to inaccuracies in lung volume measurements. The purpose of this study was to compare lung volume parameters obtained by whole body plethysmography with those determined by the commonly used nitrogen washaut technique among individuals with SCI.

Participants: Twenty-nine clinically stable men, 14 with chronic tetraplegia (injury C4-C7) and 15 with paraplegia (injury below T5) participated in the study.

Methods: Lung volumes were obtained using whole body plethysmography and the open-circuit nitrogen washout technique. Within both study groups, data were evaluated by the paired Student’st test and by determination of correlation coefficients.

Results: No statistically significant differences for any lung volume parameter were found within either group. ln subjects with tetraplegia on paraplegia, respectively, strong correlation coefficients were found for measurements of totallung capacity (.8 6 and .97), functional residual capacity (.87 and .96), and residual volume (.77 and .85).

Conclusion: These findings indicate that body plethysmography is a valid technique for determining lung volumes among subjects with SCI. Because airway resistance measurements can also be obtained du ring same study sessions for assessment of airway caliber and bronchial responsiveness, body plethysmography is a useful tool for examining multiple aspects of pulmonary physiology in this population.  相似文献   
56.
PURPOSE: To evaluate speech recognition in patients with focal intractable epilepsy and surgical resections in the nondominant (right) hemisphere. METHODS: Speech recognition was tested prospectively, under different listening conditions, in 22 patients with right temporal lobe (11 patients) or extra-temporal lobe epilepsy. All were left-hemisphere dominant for language on preoperative intracarotid sodium amobarbital testing. RESULTS: All patients demonstrated normal auditory recognition of words and environmental sounds before and after surgery. However, when real-world listening conditions were simulated by using acoustically degraded (filtered) words, patients with temporal lobe epilepsy performed significantly worse than patients with frontal or parietooccipital lobe epilepsy before and after surgery (p<0.0001). CONCLUSIONS: Patients with intractable right temporal lobe epilepsy are at risk for speech recognition impairments in real-world listening environments, independent of surgery. The impact of speech recognition difficulties on verbal communication, coupled with the prevalence of adverse listening environments, underscores the importance of testing speech recognition under different listening conditions in patients with intractable right temporal lobe epilepsy.  相似文献   
57.
Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum.  相似文献   
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