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981.
We present and illustrate the MRI appearances of two children with choroid plexus carcinoma. The MRI characteristics of these rare tumours are reviewed. Since total surgical resection is a significant prognostic factor, early postoperative MRI was performed in both cases to ensure surgical clearance. In one case a complete resection was documented and this patient remains well at short-term follow-up. Residual tumour was noted in the second case, but despite "second look" surgery there was subsequent local relapse. 相似文献
982.
Fulco CS Friedlander AL Muza SR Rock PB Robinson S Lammi E Baker-Fulco CJ Lewis SF Cymerman A 《Aviation, space, and environmental medicine》2002,73(8):758-765
BACKGROUND: Physical performance of sea-level (SL) residents acutely exposed to altitude (ALT) is diminished and may improve somewhat with ALT acclimatization. HYPOTHESIS: A large reduction in lean body mass (LBM), due to severe energy intake deficit during the first 21 d of ALT (4300 m) acclimatization, will adversely affect performance. METHODS: At ALT, 10 men received a deficit (DEF) of 1500 kcal x d(-1) below body weight (BW) maintenance requirements and 7 men received adequate (ADQ) kcal x d(-1) to maintain BW. Performance was assessed by: 1) maximal oxygen uptake (VO2max); 2) time to complete 50 cycles of a lift and carry task (L+C); 3) number of one-arm elbow flexions (10% BW at 22 flexions x min(-1); and 4) adductor pollicis (AP) muscle strength and endurance time (repeated 5-s static contractions at 50% of maximal force followed by 5-s rest, to exhaustion). Performance and body composition (using BW and circumference measures) were determined at SL and at ALT on days 2 through 21. RESULTS: At SL, there were no between-group differences (p > 0.05) for any of the performance measures. From SL to day 21 at ALT, BW and LBM declined by 6.6 +/- 3 kg and 4.6 kg, respectively, for the DEF group (both p < 0.01), but did not change (both p > 0.05) for the ADQ group. Performance changes from day 2 or 3 to day 20 or 21 at ALT were as follows (values are means +/- SD): VO2max (ml x min(-1)): DEF = +97 +/- 237, ADQ = +159 +/- 156; L + C (s): DEF = -62 +/- 35*, ADQ = -35 +/- 20* (*p < 0.05; improved from day 3); arm flex (reps): DEF = -2 +/- 7, ADQ = +2 +/- 8; AP endurance (min): DEF = +1.4 +/- 2, ADQ = + 1.9 +/- 2; AP strength (kg): DEF = -0.7 +/- 4, ADQ = -1.2 +/- 2. There were no differences in performance between groups. CONCLUSIONS: A significant BW and LBM loss due to underfeeding during the first 21 d of ALT acclimatization does not impair physical performance at ALT. 相似文献
983.
Incidence of symptomatic thrombosis in a stable population of 650,000: travel and other risk factors
Despite recent intensive media interest, the incidence of traveler's thrombosis is unknown. We have undertaken a study of all symptomatic cases of venous thrombosis, presenting to a hospital, in a fixed population of 650,000. There were 1,250 cases of venous thromboembolism diagnosed over a 2-yr period. Of these, only 47 (3.8%) answered positively to the question" did you make a journey of more than 100 mi in the 4 wk prior to diagnosis?" Among the travelers, 60% had traveled by air, 36% by road, and the remainder by rail. At least one medical risk factor for venous thrombosis was present in all but three of our cohort. We conclude that, taking into consideration the enormous number of passengers who travel, the relative risk of traveler's thrombosis is likely to be low. The incidence of this complication in the North East of England is 1 per 27,660 of the whole population. 相似文献
984.
The authors describe a distinct clinical entity consisting of bony tenderness, increased isotope uptake along the metaphyses and/or diaphyses and magnetic resonance changes simulating a bone marrow-replacing lesion. Bone biopsies indicate the presence of bone marrow fibrosis and some new bone formation. Nine such cases were prospectively evaluated according to a standardized protocol including clinical examination, x-rays, bone scan and CT scan as well as MRI scans including contrast medium injection. All patients presented with tibial tenderness. In one case the bone was noticeably thicker as compared to the other side. The ages ranged from 6 years to 64 years and 6 of the patients were female. Xrays were normal in 6/9 patients; the rest had minimal periosteal reaction, and mild intramedullary sclerosis. Uniform imaging findings were longitudinal increased uptake along the metadiaphysis of the tibia on bone scans, and increased bone marrow density on CAT scans without a fracture line. A magnetic resonance study indicated bone marrow replacement as demonstrated by an area of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Some enhancement of signal was observed following gadolinium injection. This clinical entity, which the authors attribute to be a medullary stress reaction, is self-limited, and pain resolves within 3 months. However the radiographic changes appear to be permanent. A biopsy is not required provided no cortical penetration or soft tissue mass is demonstrated by MRI scan. 相似文献
985.
BACKGROUND: Head and neck surgeons commonly request frozen sections. Practice patterns vary from laboratory to laboratory on how the tissue is used in performing the frozen section. Some pathologists wish to see all the material submitted by consuming it completely during frozen section, whereas others reserve some for permanent section. We wished to determine whether knowledge of margin status was initially inaccurate because of reserving tissue for permanent section. METHODS: Sixty-five laryngectomies (total and partial) with margin assessment enhanced by frozen section evaluation were studied. Forty-five laryngectomy specimens, generating 249 frozen sections in which a permanent section was prepared from tissue remaining from frozen section examination, were studied. RESULTS: Five of the 249 frozen sections contained a discrepancy between the frozen section and permanent section because of insufficient leveling of the frozen section block. These five discrepancies were called negative on frozen section, but permanent section revealed dysplasia (two cases of mild dysplasia, one case with moderate dysplasia, and one case with severe dysplasia) or carcinoma in situ (one case). Twenty laryngectomies in which the frozen section tissue was consumed at the time of frozen section generated 103 frozen sections. In eight of the frozen sections involving six cases, the diagnostic tissue was not present on one or two of the frozen section levels examined. CONCLUSIONS: We conclude that in examining margins for laryngeal squamous cell carcinoma the frozen section tissue should be completely sampled by examining several levels at the time of frozen section. This requires consuming or exhausting the frozen section tissue rather than reserving any remaining frozen tissue for a paraffin-embedded permanent section. 相似文献
986.
Presentation, treatment, and outcome of oral cavity cancer: a National Cancer Data Base report 总被引:7,自引:0,他引:7
BACKGROUND: Oral cancer has been identified as a significant public health threat. Systematic evaluation of the impact of this disease on the US population is of great importance to health care providers and policy makers. METHODS: This study used the National Cancer Data Base (NCDB) to evaluate associations between demographic and disease characteristics, treatment, and survival for patients with oral cavity cancer in the United States. Of patients diagnosed between 1985 and 1996, 58,976 were extracted from the NCDB. ANOVAs were performed on selected cross-tabulations, and relative survival was used to calculate outcome. RESULTS: Median age of patients was 64.0 years. Men made up 60.2% of patients. Pathologic diagnosis was squamous cell carcinoma (SCC) in 86.3% of cases. Younger patients had a much higher frequency of non-SCC, and this was related to survival in these patients. African-Americans (independent of income), lower income patients, and patients with higher grade disease were seen more frequently with advanced-stage SCC. Five-year relative survival for SCC cases was lower for older patients, men, and African-Americans. CONCLUSIONS: This study addressed many issues related to oral cancer that have been previously discussed in the literature. The demographic, site, stage, histologic, and survival data available for this large number of cases in the NCDB allowed an accurate characterization of the contemporary status of oral cancer in the United States. 相似文献
987.
Prioritizing patients for elective surgery: clinical judgement summarized by a Linear Analogue Scale
Background: The New Zealand health reforms have resulted in the requirement that surgeons utilize Clinical Priority Access Criteria (CPAC) to ration patient access to elective surgery. The validity of the tools used as CPAC has been challenged. An alternative tool, the Linear Analogue Scale (LAS), is therefore used in our institution. Our objectives were to determine the variables that influence the priority score generated using the LAS, and the length of time waited by patients awaiting general surgical procedures. Methods: A cohort of 918 patients who were listed for elective general surgical procedures at Auckland Hospital, Auckland, New Zealand between 1 July 1998 and 31 March 1999 were studied. Patients were given a priority score generated using the LAS. For each patient, the time from assessment until his or her procedure was documented. Linear and logistic regression models were used to investigate variables (age, gender, diagnosis and surgical team) that influence priority score. Cox proportional hazards models were used to investigate variables (priority score, age, gender, and diagnosis) that influence the length of time waited. Results: Graphical presentation showed a pattern of priority scores falling into ‘bands’ for different diagnoses. Diagnosis, and to a lesser extent surgical team, influenced priority score. Survival analysis showed ‘time waited’ to be influenced by priority score, diagnosis, and patient age and gender. Conclusion: The LAS may have a useful role in the difficult sphere of patient prioritization. Its strength lies in its simplicity. Further investigation of reliability and effect on patient outcomes is required. 相似文献
988.
Background. Malignant hyperthermia (MH) is an inherited, potentiallyfatal, pharmocogenetic disorder triggered by certain anaestheticagents. In light of the reported genetic heterogeneity for thedisorder and the recent introduction of DNA testing guidelinesfor the trait, we have assessed the role of the CACNA1S genein MH susceptibility in UK patients. Linkage to this locus haspreviously been demonstrated in several European MH families. Methods and results. We screened 200 unrelated MH-susceptibleindividuals for known CACNA1S mutations. With the aim to characterizefurther novel mutations at this locus, functionally relevantregions of the gene were also sequenced in 10 unrelated individualsfrom families where the involvement of other MH susceptibilityloci was unlikely. No sequence variations were detected in anyof the patients investigated. Conclusions. Defects in CACNA1S are not a major cause of MHin the UK population. Diagnostic screening of this gene is unlikelyto be of value to UK MH patients in the near future. Br J Anaesth 2002; 88: 5879 相似文献
989.
990.
Which parameters of beat-to-beat blood pressure and variability best predict early outcome after acute ischemic stroke? 总被引:12,自引:0,他引:12
Dawson SL Manktelow BN Robinson TG Panerai RB Potter JF 《Stroke; a journal of cerebral circulation》2000,31(2):463-468
BACKGROUND AND PURPOSE: In hypertensive populations, increasing blood pressure (BP) levels and BP variability (BPV) are associated with a greater incidence of target organ damage. After stroke, elevated 24-hour BP levels predict a poor outcome, although it is uncertain whether shorter-length BP recordings assessing mean BP levels and BPV have a similar predictive role. The objectives of this study were to compare the different measures of beat-to-beat BP and BPV on outcome after acute ischemic stroke and assess whether these parameters were affected by stroke subtype. METHODS: Ninety-two consecutive admissions with a CT-confirmed diagnosis of acute ischemic stroke were recruited, of whom 54 had cortical infarction, 29 subcortical, and 9 posterior circulation infarction. Casual and two 5-minute recordings of beat-to-beat BP (Finapres, Ohmeda) were made under standardized conditions within 72 hours of ictus, with mean BP levels taken as the average of this 10-minute recording and BPV as the standard deviation. Outcome was assessed at 30 days as dead/dependent or independent (Rankin =2). The effects of BP, BPV, and stroke subtype on outcome were studied with the use of logistic regression. Stroke subjects were subsequently divided by BP quartiles and within each quartile into low- and high-variability groups; the influence of high BPV on outcome was also assessed. RESULTS: The odds ratio for death/dependency was significantly higher in cortical strokes compared with subcortical and posterior circulation strokes even after controlling for differences in BP and BPV (OR 4.19, P=0.002). Beat-to-beat systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP +/- SD) levels were higher in the dead/dependent group compared with the independent group (MAP 106+/-20.4 mm Hg vs 97+/-19.1 mm Hg, P<0.02), as was MAP variability: 6.1 (interquartile range 4.5 to 7.4 mm Hg) versus 4.9 (3.8 to 6.4 mm Hg, P=0.02). The odds ratio for a poor outcome was 1. 38 (P=0.014) for every 10-mm Hg increase in MAP and 1.32 (P=0.02) for every 1-mm Hg increase in MAP variability. Casual BP measurements had no prognostic significance. For the group as a whole when separated into BP quartiles, those with a high MAP and DBP but not SBP variability within each quartile had a worse prognosis compared with those with a low BPV. CONCLUSIONS: A poor outcome at 30 days after ischemic stroke was dependent on stroke subtype, beat-to-beat DBP, and MAP levels and variability. Important prognostic information can be readily obtained from a short period of noninvasive BP monitoring in the acute stroke patient. These findings have important implications, particularly regarding the use of hypotensive agents in the acute stroke period. 相似文献