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61.
We studied the brain activation patterns in two visual image processing tasks requiring judgements on object construction (FIT task) or object sameness (SAME task). Eight right-handed healthy human subjects (four women and four men) performed the two tasks in a randomized block design while 5-mm, multislice functional images of the whole brain were acquired using a 4-tesla system using blood oxygenation dependent (BOLD) activation. Pairs of objects were picked randomly from a set of 25 oriented fragments of a square and presented to the subjects approximately every 5 sec. In the FIT task, subjects had to indicate, by pushing one of two buttons, whether the two fragments could match to form a perfect square, whereas in the SAME task they had to decide whether they were the same or not. In a control task, preceding and following each of the two tasks above, a single square was presented at the same rate and subjects pushed any of the two keys at random. Functional activation maps were constructed based on a combination of conservative criteria. The areas with activated pixels were identified using Talairach coordinates and anatomical landmarks, and the number of activated pixels was determined for each area. Altogether, 379 pixels were activated. The counts of activated pixels did not differ significantly between the two tasks or between the two genders. However, there were significantly more activated pixels in the left (n = 218) than the right side of the brain (n = 161). Of the 379 activated pixels, 371 were located in the cerebral cortex. The Talairach coordinates of these pixels were analyzed with respect to their overall distribution in the two tasks. These distributions differed significantly between the two tasks. With respect to individual dimensions, the two tasks differed significantly in the anterior--posterior and superior--inferior distributions but not in the left--right (including mediolateral, within the left or right side) distribution. Specifically, the FIT distribution was, overall, more anterior and inferior than that of the SAME task. A detailed analysis of the counts and spatial distributions of activated pixels was carried out for 15 brain areas (all in the cerebral cortex) in which a consistent activation (in > or = 3 subjects) was observed (n = 323 activated pixels). We found the following. Except for the inferior temporal gyrus, which was activated exclusively in the FIT task, all other areas showed activation in both tasks but to different extents. Based on the extent of activation, areas fell within two distinct groups (FIT or SAME) depending on which pixel count (i.e., FIT or SAME) was greater. The FIT group consisted of the following areas, in decreasing FIT/SAME order (brackets indicate ties): GTi, GTs, GC, GFi, GFd, [GTm, GF], GO. The SAME group consisted of the following areas, in decreasing SAME/FIT order : GOi, LPs, Sca, GPrC, GPoC, [GFs, GFm]. These results indicate that there are distributed, graded, and partially overlapping patterns of activation during performance of the two tasks. We attribute these overlapping patterns of activation to the engagement of partially shared processes. Activated pixels clustered to three types of clusters : FIT-only (111 pixels), SAME-only (97 pixels), and FIT + SAME (115 pixels). Pixels contained in FIT-only and SAME-only clusters were distributed approximately equally between the left and right hemispheres, whereas pixels in the SAME + FIT clusters were located mostly in the left hemisphere. With respect to gender, the left-right distribution of activated pixels was very similar in women and men for the SAME-only and FIT + SAME clusters but differed for the FIT-only case in which there was a prominent left side preponderance for women, in contrast to a right side preponderance for men. We conclude that (a) cortical mechanisms common for processing visual object construction and discrimination involve mostly the left hemisphere, (b) cortical mechanisms specific for these tasks engage both hemispheres, and (c) in object construction only, men engage predominantly the right hemisphere whereas women show a left-hemisphere preponderance.  相似文献   
62.
Aim The aim of the study was to evaluate the impact of vitiligo on the quality of life and psychological adaptation in a Korean adolescent population. Methods Fifty‐seven adolescents aged 12 to 18 years with vitiligo were evaluated using self‐report scales, namely the Skindex‐29, Piers‐Harris self‐concept, Center for Epidemiologic Studies Depression Scale (CES‐D), and Revised Children’s Manifest Anxiety Scale (RCMAS). Results Mean Skindex‐29 subscales were as follow; 21.8 (global), 16.3 (symptom), 18.6 (function) and 29.5 (emotion). Several clinical variables, such as duration of vitiligo, facial involvement, history of previous treatment, and patient‐assessed severity, affected the Skindex‐29 subscales in various ways. However, differences in Skindex‐29 scores according to the type of vitiligo, extent of involvement, and family history were not observed. The Piers‐Harris self‐concept scores showed a negative correlation with Skindex‐29 scores, while other psychological measures (CES‐D and RCMAS) were positively correlated. Conclusion The quality of life of adolescents with vitiligo is closely related to the patients’ apprehensions about their disease, psychosocial adjustment, and psychiatric morbidity, rather than the clinical severity of the condition itself. Clinicians should recognize and deal with psychological adaptation along with medical intervention when treating adolescent patients with vitiligo.  相似文献   
63.
64.
Limited therapeutic options are available for vancomycin intermediate-resistant Staphylococcus Epidermidis (VISE) infections and no optimum therapy has been established. We report a case of VISE skull osteomyelitis that was successfully treated with linezolid. The patient was a 53-year-old man who presented with headache, nausea and dysphasia. Brain computerized tomography (CT) demonstrated a subdural hematoma in the left hemisphere. Craniotomy and hematoma evacuation was performed and he showed good recovery despite a scalp wound infection caused by methicillin-resistant Staphylococcus aureus (MRSA). The organism isolated from the scalp wound was sensitive to vancomycin. The patient was treated with intravenous vancomycin for 44 days. However, he showed a high fever, persistent positive methicillin-resistant Staphylococcus Epidermidis (MRSE) blood cultures, and a deteriorating clinical status. He underwent infected skull bone flap removal and linezolid treatment for 35 days. During one year of follow up, he has not had any further episodes of osteomyelitis or fever. Linezolid has shown to be effective agent to eradiate osteomyelitis caused by VISE.  相似文献   
65.
Estimation of the incremental cost-effectiveness ratio (ICER) is difficult for several reasons: treatments that decrease both cost and effectiveness and treatments that increase both cost and effectiveness can yield identical values of the ICER; the ICER is a discontinuous function of the mean difference in effectiveness; and the standard estimate of the ICER is a ratio. To address these difficulties, we have developed a Bayesian methodology that involves computing posterior probabilities for the four quadrants and separate interval estimates of ICER for the quadrants of interest. We compute these quantities by simulating draws from the posterior distribution of the cost and effectiveness parameters and tabulating the appropriate posterior probabilities and quantiles. We demonstrate the method by re-analysing three previously published clinical trials.  相似文献   
66.
Malignant transformation of a mature cystic teratoma (MCT) is an uncommon complication. The most common form of malignant transformation of a MCT is squamous cell carcinoma, representing 75% of malignant transformations. The frequency of malignant transformation of MCT to adenocarcinoma is just 6.8%. To the best of our knowledge, no case of para-aortic lymph node metastasis in mucinous adenocarcinoma arising from MCT has been reported before. The prognosis of malignant transformation of the MCT is very poor. Here, we report an unusual case of a 41-year-old woman with mucinous adenocarcinoma arising from MCT with para-aortic lymph node metastasis.  相似文献   
67.
Coccydynia     
Coccydynia is a term that refers to pain in the region of the coccyx. Most cases are associated with abnormal mobility of the coccyx which may trigger a chronic inflammatory process leading to degeneration of this structure. In some patients this instability may be detected on dynamic radiographs. Nonsurgical management remains the gold standard treatment for coccydynia, consisting of decreased sitting, seat cushioning, coccygeal massage, stretching, manipulation, local injection of steroids or anesthetics, and postural adjustments. Those patients who fail these conservative modalities may potentially benefit from coccygectomy. However, surgical intervention is typically reserved for patients with evidence of advanced coccygeal instability (e.g., subluxation or hypermobility) or spicule formation, as this population appears to exhibit the greatest improvement postoperatively.  相似文献   
68.

Background  

Placement of stents may be an alternative option to treat gastrojejunal (GJ) anastomotic leaks after Roux-en-Y gastric bypass (RYGB) surgery. The aim was to evaluate the performance of a covered metal stent (Alimaxx-E, 18 × 100 mm) across a GJ leak in a porcine model.  相似文献   
69.
The extent of lymphadenectomy for esophageal adenocarcinoma remains controversial. Outstanding issues include the appropriate technical approach such as transthoracic versus transhiatal, or open versus minimally invasive, both of which have implications on overall lymph node harvest numbers and morbidity. Recent data on the relationship of total number of lymph nodes harvested and oncologic survival have been conflicting, due in part to a likely differential impact of lymphadenectomy on survival based on tumor stage and response to neoadjuvant therapy. While standardizing the extent of lymphadenectomy may be desirable, a more useful approach might be to tailor lymphadenectomy considering the multidimensional impact of surgical technique and multimodal treatment strategy.  相似文献   
70.
Various guidelines have been proposed regarding which portions of a surgical gown may be considered sterile. Unfortunately, the validity of these recommendations has not been definitively established. We therefore evaluated gown sterility after major spinal surgery to assess the legitimacy of these guidelines. We used sterile culture swabs to obtain samples of gown fronts at 6-inch increments and at the elbow creases of 50 gowns at the end of 29 spinal operations. Another 50 gowns were swabbed immediately after they were applied to serve as negative controls. Bacterial growth was assessed using semiquantitative plating techniques on a nonselective, broad-spectrum media. Contamination was observed at all locations of the gown with rates ranging from 6% to 48%. Compared with the negative controls, the contamination rates were greater at levels 24 inches or less and 48 inches or more relative to the ground and at the elbow creases. The section between the chest and operative field had the lowest contamination rates. Based on these results, we consider the region between the chest and operative field to be the most sterile and any contact with the gown outside this area, including the elbow creases, should be avoided to reduce the risk of infection. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research.  相似文献   
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