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101.
PURPOSE: To prospectively evaluate ferumoxtran-10-enhanced magnetic resonance (MR) imaging for nodal staging in patients with urinary bladder cancer. MATERIALS AND METHODS: Fifty-eight patients with proved bladder cancer were enrolled. Results of MR imaging performed before and after injection of ferumoxtran-10 were compared with histopathologic results in surgically removed lymph nodes. High-spatial-resolution three-dimensional T1-weighted magnetization-prepared rapid acquisition gradient-echo (voxel size, 1.4 x 1.4 x 1.4 mm) and T2*-weighted gradient-echo (voxel size, 0.8 x 0.8 x 3.0 mm) sequences were performed before and 24 hours after injection of ferumoxtran-10 (2.6 mg iron per kilogram of body weight). On precontrast images, lymph nodes were defined as malignant by using size and shape criteria (round node, >8 mm; oval, >10 mm axial diameter). On postcontrast images, nodes were considered benign if there was homogeneous decrease in signal intensity and malignant if decrease was absent or heterogeneous. Qualitative evaluation was performed on a node-to-node basis. Sensitivity, specificity, predictive values, and accuracy were evaluated with logistic regression analysis. RESULTS: In 58 patients, 172 nodes imaged with use of ferumoxtran-10 were matched and correlated with results of node dissection. Of these, 122 were benign and 50 were malignant. With nodal size and shape criteria, accuracy, sensitivity, specificity, and positive and negative predictive values on precontrast images were 92%, 76%, 99%, 97%, and 91%, respectively; corresponding values on postcontrast images were 95%, 96%, 95%, 89%, and 98%. In the depiction of pelvic metastases, sensitivity and negative predictive value improved significantly at postcontrast compared with those at precontrast imaging, from 76% to 96% (P < .001) and from 91% to 98% (P < .01), respectively. At postcontrast imaging, metastases (4-9 mm) were prospectively found in 10 of 12 normal-sized nodes (<10 mm); these metastases were not detected on precontrast images. Postcontrast images also showed lymph nodes that were missed at pelvic node dissection in two patients. CONCLUSION: Ferumoxtran-10-enhanced MR imaging significantly improves nodal staging in patients with bladder cancer by depicting metastases even in normal-sized lymph nodes.  相似文献   
102.
OBJECTIVE: Excessive daytime sleepiness (EDS) and sleep complaints are common among adults with epilepsy. We hypothesized that children with epilepsy have worse daytime sleepiness compared with controls. METHODS: Children with and without epilepsy between ages 8 and 18 were recruited for the study. Parents and children were asked to fill out the Pediatric Sleep Questionnaire (PSQ) and Pediatric Daytime Sleepiness Scale (PDSS), respectively. The Mann-Whitney U test was used for group comparisons, with the Fischer exact or chi2 test for categorical variables. Regression analysis was used to identify predictors of EDS. RESULTS: Twenty-six patients and matched controls were recruited for the study. Parents of children with epilepsy more often reported EDS (P < 0.001), symptoms of sleep-disordered breathing (P < 0.001), and parasomnias (P < 0.001) compared with controls. On the PDSS, children with epilepsy reported worse daytime sleepiness scores compared with controls (15.48 +/- 6.4 vs 11.88 +/- 5.25, P = 0.037). Based on conditional logistic regression modeling, symptoms of excessive daytime sleepiness [corrected] (OR = 15.3, 95% CI = 1.4-166.6) and parasomnias (OR = 12.4, 95% CI = 1.01-151.6) were significantly associated with having epilepsy when adjusted for duration of nightime sleep. Further, 10 children (38.5%) with epilepsy reported positive sleep-disordered breathing, whereas no one in the control group reported SDB (P < 0.001) [corrected] Epilepsy syndrome, anticonvulsants used, and presence or absence of seizure freedom, however, were not significant predictors of EDS among patients. CONCLUSIONS: Daytime sleepiness appears to be common in children with epilepsy, and may be due to underlying sleep disorders. Further confirmatory studies are needed using screening questionnaires and formal sleep studies to systematically study the prevalence of sleep complaints and role of sleep disorders in these patients.  相似文献   
103.
104.
The objective of this study was to evaluate the age distribution, mode of injury, type of hematomas, and their surgical outcome in patients with bilateral traumatic head injuries. The present study included 669 cases of traumatic head injury who presented at the neurosurgery emergency out of which 94 cases had bilateral head injuries from the period of August 2009 to April 2014. The data from the hospital computerized database were retrospectively analysed. Cases of bilateral traumatic head injury included 94 patients out of which 88.29 % (n?=?83) were males and 11.70 % (n?=?11) were females. Commonest mode of injury was road traffic accident in 56.38 % (n?=?53) followed by fall from height in 29.78 % (n?=?28). In our study, 25.53 % patients had epidural hematoma (EDH) with intracerebral hematoma (ICH) or contusion (n?=?24), followed by EDH with subarachnoid hemorrhage (SAH) in 18.08 % (n?=?17). At the time of discharge, all those patients managed conservatively had good Glasgow outcome scale (GOS) while with surgical intervention 58 % patients had good GOS, 19 % had moderate disability, and 9 % remained with severe disability. In cases of bilateral hematomas, EDH is most common and should be managed in neurosurgical emergency. Other combinations of bilateral intracranial hematomas should be managed according to the surgical indication and serial CT imaging.  相似文献   
105.
PURPOSE: To optimally integrate epidermal growth factor receptor (EGFR) inhibitors into the clinical treatment of head and neck cancer, two important questions must be answered: (a) does EGFR inhibition add to the effects of radiochemotherapy, and (b) if so, which method of inhibiting EGFR is superior (an EGFR antibody versus a small molecule tyrosine kinase inhibitor)? We designed an in vivo study to address these questions. EXPERIMENTAL DESIGN: Nude mice with UMSCC-1 head and neck cancer xenografts received either single, double, or triple agent therapy with an EGFR inhibitor (either cetuximab or gefitinib), gemcitabine, and/or radiation for 3 weeks. Tumor volumes and animal weights were measured for up to 15 weeks. Immunoblotting and immunofluorescent staining were done on tumors treated with either cetuximab or gefitinib alone. RESULTS: The addition of an EGFR inhibitor significantly delayed the tumor volume doubling time, from a median of 40 days with radiochemotherapy (gemcitabine and radiation) alone, to 106 days with cetuximab and 66 days with gefitinib (both P < 0.005). Cetuximab resulted in significantly less weight loss than gefitinib. Immunoblot analysis and immunofluorescent staining of tumors show that although levels of phosphorylated AKT and extracellular signal-regulated kinase were decreased similarly in response to cetuximab or gefitinib, cetuximab caused prolonged suppression of pEGFR, pSTAT3, and Bcl(XL) compared with gefitinib. CONCLUSIONS: EGFR inhibition, particularly with cetuximab, improves the effectiveness of radiochemotherapy in this model of head and neck cancer. The correlation of response with prolonged suppression of EGFR, STAT3, and Bcl(XL) offers the possibility that these may be candidate biomarkers for response.  相似文献   
106.
107.
The nocturnal serum of 13 nongrowth hormone deficient, hyposomatomedinemic short children and of 12 normal children of average height was analyzed by both polyclonal and biclonal radioimmunoassays. The biclonal/polyclonal ratio for immunochemical grade human growth hormone was 1.0, but for the nocturnal sera in both groups, this ratio was significantly less than 1.0 (range 0.5-1.2, average 0.7-0.8). The ratio did not differ significantly between the two groups of children.  相似文献   
108.
The diagnosis of necrotizing enterocolitis (NEC) in neonates may be made by clinical presentation, roentgenographic findings, or a combination of both. Diagnosis leads to immediate treatment including nasogastric suction, parenteral antibiotics, plasma, and close monitoring of clinical, roentgenographic, and laboratory findings. Occasionally, neither the clinical nor plain roentgenographic appearance of an infant allows the diagnosis of NEC to be made or excluded with confidence. In such infants portable isotonic metrizamide gastrointestinal (GI) series were used to help make the decision of whether to begin treatment for NEC or to continue feeding the patient. Of 15 patients examined, two exhibited signs of NEC and were successfully treated medically without GI (tract) sequelae. Twelve neonates had normal results of metrizamide GI series and ten were immediately fed with no GI complication. One of these 12 infants had feedings withheld for several days as a result of a positive blood culture. One infant with severe cardiac and pulmonary disease had profound adynamic ileus and could not be fed. We have found the metrizamide GI series to be a useful study in neonates suspected of having NEC.  相似文献   
109.
The short child with subnormal plasma somatomedin C   总被引:1,自引:0,他引:1  
In 59 male and 59 female healthy children of average stature between 7 and 10 yr old, the normal range of plasma somatomedin C was investigated. The 95% tolerance limits narrowed progressively when the child's plasma somatomedin C status was described by the mean of one, two, three, or four determinations at 6-wk intervals. The 95% tolerance limits were therefore based on the mean of four determinations. In 97 children, age 7 to 10, below the 3.0 percentile in height, 44 had an average plasma somatomedin C below the 2.5 percentile. Among these hyposomatomedinemic short children, 19 were partially or totally deficient in growth hormone, 20 had normal immunoreactive growth hormone responses to dopa, glucagon, and sleep (nongrowth hormone deficient), and five had borderline provocative tests. Both growth hormone deficient and nongrowth hormone deficient children showed significant linear growth responses to 6-month courses of human growth hormone (0.16 to 0.70 unit/kg/wk). The responses of the latter group were 50 to 90% as great as those of the former.  相似文献   
110.
Haemangiopericytoma of the nose and paranasal sinuses   总被引:1,自引:0,他引:1  
The uncertain course and rarity of haemangiopericytoma in the nose and paranasal sinuses has interested both pathologists and clinicians. This tumour arises from proliferation of pericytes which invest capillary endothelium. A benign course is more common in the nose and paranasal sinuses. The first nasal haemangiopericytoma was reported by Stout in 1949. Since then only twenty cases have been reported in the literature. We present three further cases.  相似文献   
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