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961.
Bird VG Gomez-Marin O Leveillee RJ Sfakianakis GN Rivas LA Amendola MA 《The Journal of urology》2002,167(4):1597-1603
PURPOSE: We assessed unenhanced helical computerized tomography (CT) secondary findings as predictors of renal obstruction as determined by diuretic scintirenography, and determined their reproducibility. MATERIALS AND METHODS: We performed a retrospective review of the records of 77 consecutive patients with unenhanced helical CT findings (stones and secondary findings, including renal parenchymal edema, hydronephrosis, hydroureter, perinephric fat stranding, periureteral fat stranding and extravasation) of urinary lithiasis who had also undergone concomitant diuretic scintirenography during the initial emergency room evaluation during a 1-year period. Unenhanced helical CT films were independently reviewed by 2 attending radiologists (blinded to clinical outcome) to determine interobserver variability. The results were compared to those of diuretic scintirenography. RESULTS: Considerable interobserver variability, as evidenced by kappa values ranging from 0.26 to 0.60, existed for the diagnosis of secondary findings associated with urinary lithiasis on unenhanced helical CT. There was no significant difference in terms of CT findings between patients diagnosed by diuretic scintirenography as having high grade/complete obstruction and those with partial obstruction (p values 0.24 to 0.85 for the 6 unenhanced helical CT findings analyzed). Analyses of variance followed by Tukey's pairwise comparisons showed no significant difference in average number of unenhanced helical CT findings between patients with high grade/complete obstruction (mean plus or minus standard deviation 4.4 +/- 1.31), partial obstruction (4.4 +/- 1.30), and decompression/no obstruction (4.2 +/- 1.16). However, the mean number of unenhanced helical CT findings for patients with normal scintirenography/no obstruction (1.9 +/- 1.41) was significantly different from each of the other 3 diuretic scintirenography groups. Separate logistic regression analyses showed that each unenhanced helical CT finding, except for renal parenchymal edema and urinary extravasation, was a significant predictor of "any degree of obstruction" (high grade and partial obstruction groups) compared to "no obstruction" (decompressed and no obstruction groups). Odds ratios (95% confidence interval) ranged from 6.15 (2.25, 16.82) for perinephric fat stranding to 3.41 (1.30, 8.97) for hydroureter. When these analyses were repeated after exclusion of 8 patients with bladder/passed stones, only perinephric fat stranding and periureteral fat stranding remained significant predictors of "any degree of obstruction," with respective odds ratios of 4.21 (1.49, 11.91) and 4.08 (1.31, 12.65). CONCLUSIONS: Measures of agreement between trained, independent radiologists with respect to unenhanced helical CT secondary findings show considerable variability. The average number of CT consensus findings is not helpful in differentiating patients with variable degrees of obstruction, except for those with normal scintirenography/no obstruction. Unenhanced helical CT findings, except for renal parenchymal edema and urinary extravasation, are significant predictors of "any degree of obstruction" (high grade or partial obstruction) compared to "no obstruction" (decompressed or no obstruction). Therefore, unenhanced helical CT findings may be useful for identifying patients with any degree of obstruction but do not differentiate between those with high grade and partial obstruction. 相似文献
962.
963.
Clinical pattern and pathologic stage but not histologic features predict outcome for bronchioloalveolar carcinoma 总被引:11,自引:0,他引:11
Ebright MI Zakowski MF Martin J Venkatraman ES Miller VA Bains MS Downey RJ Korst RJ Kris MG Rusch VW 《The Annals of thoracic surgery》2002,74(5):1640-6; discussion 1646-7
BACKGROUND: The histologic criteria defining bronchioloalveolar carcinoma (BAC) were recently revised, but it is unclear whether these criteria predict clinical behavior. This study determined the outcome of resected BAC in relationship to clinical and radiologic disease pattern, and pathologic features. METHODS: Between 1989 and 2000, 100 consecutive surgically treated patients with adenocarcinomas exhibiting various degrees of BAC features were retrospectively studied. Histology was reviewed; tumors were classified as pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features. Clinical and radiologic pattern were classified as unifocal, multifocal, or pneumonic. Demographic data, tumor stage, and outcome were recorded. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were determined by the log-rank test. RESULTS: Patient median age was 65, and 74% of the patients were female. Pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features occurred in 47, 21, and 32 patients, respectively. Unifocal disease occurred in 64 patients, multifocal in 29, and pneumonic in 7. Seventy-one patients had stage I/II tumors, 22 had stage III/IV, and 7 patients had Stage X tumors. Overall 5-year survival was 74%. There was no significant difference in survival among the three histologic subtypes. The pneumonic pattern had significantly worse survival compared with unifocal and multifocal patterns. Pathologic stage predicted survival, with 5-year survivals for I/II and III/IV of 83.7% and 59.6%, respectively. CONCLUSIONS: Clinical pattern and pathologic stage, but not the degree of invasion on histologic examination predict survival. Multifocal disease is associated with excellent long-term survival after resection. The favorable survival of stage III/IV BAC indicates that the current staging system does not fully describe this disease in patients undergoing resection because of its distinct tumor behavior. 相似文献
964.
Prion diseases is another name for a group of 'transmissible spongiform encephalopathies'. Creutzfeldt-Jakob disease, the first prion disease described in humans, occurs in sporadic, familial or iatrogenic form. Other transmissible spongiform encephalopathies in humans such as familial Creutzfeldt-]akob disease, Gerstmann-Str?ussler-Scheinker disease and fatal familial Insomnia have been shown to be associated with specific prion protein gene mutations. In 1996, a new variant of Creutzfeldt-Jakob disease was reported in the United Kingdom among young patients with unusual clinical features and unique neuropathological findings. This new form could be due to transmission to humans of the agent causing bovine spongiform encephalopathy. While examination of brain tissue is the key to making a diagnosis, it is not always possible antemortem. Immunological tests such as ELISA or western blot assays along with tests for 1 4-3-3 protein in the cerebrospinal fluid remain the main tools of diagnosis. Conventional disinfection and sterilization practices are Ineffective for these agents. The unusual properties of prions pose a challenge for treatment, surveillance and control of these diseases. 相似文献
965.
966.
Truc P Lejon V Magnus E Jamonneau V Nangouma A Verloo D Penchenier L Büscher P 《Bulletin of the World Health Organization》2002,80(11):882-886
OBJECTIVE: To evaluate the performance of serological tests using dried blood on filter-papers (micro-card agglutination test for trypanosomiasis (micro-CATT)) performed under field and laboratory conditions and using whole blood ((CATT/T.b. gambiense) (wb-CATT) and latex agglutination (LATEX/T.b. gambiense) (wb-LATEX)) for the serodiagnosis and surveillance of human African trypanosomiasis in West and Central Africa. METHODS: We evaluated the micro-CATT, wb-CATT and wb-LATEX methods in Côte d''Ivoire and the Central African Republic by screening 940 people. Sensitivity and specificity were calculated for each serological test; only patients with the confirmed presence of trypanosomes in the blood or lymph aspirate were considered true positives. Positive and negative predictive values were also calculated. FINDINGS: Each of the tests showed a lower sensitivity in the Central African Republic than in Côte d''Ivoire. CONCLUSION: The results confirmed the efficiency of the classic wb-CATT to detect sleeping sickness patients. The micro-CATT method can be used for human African trypanosomiasis surveillance if the test is performed on the same day as the blood collection, or if samples are stored at 4 degrees C. Otherwise, micro-CATT can be used when absolute sensitivity is not required. wb-LATEX should only be used for high-specificity screening. 相似文献
967.
Hojo R Stern S Zareba G Markowski VP Cox C Kost JT Weiss B 《Environmental health perspectives》2002,110(3):247-254
Pregnant Sprague-Dawley rats received a single oral dose of 0, 20, 60, or 180 ng/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin on day 8 of gestation. Each litter contributed a single male-female pair trained to press a lever to obtain food pellets under two operant behavior procedures. Initially, each lever press was reinforced. The fixed-ratio (FR) requirement was then increased every four sessions from the initial setting of 1 to values between 6 and 71. We then studied responses for 30 days under a multiple schedule combining FR 11 and another schedule requiring a pause of at least 10 sec between responses (DRL 10-sec). TCDD evoked a sexually dimorphic response pattern. Generally, TCDD-exposed males responded at lower rates than control males. In contrast, exposed females responded at higher rates than controls. Each response measure from the mult-FR DRL schedule yielded a male-female difference score. We used the differences in response rate to calculate benchmark doses based on the relative displacement from modeled zero-dose performance of the effective dose at 1% (ED(01)) and 10% (ED(10)), as determined by a second-order polynomial fit to the dose-effect function. For the male-female difference in FR rate of responding, the mean ED(10) was 2.77 ng/kg with a 95% lower bound of 1.81 ng/kg. The corresponding ED(01) was 0.27 ng/kg with a 95% lower bound of 0.18 ng/kg. For the male-female difference in DRL rate, the mean ED(10) was 2.97 ng/kg with a 95% lower bound of 2.02 ng/kg. The corresponding ED(01) was 0.30 ng/kg with a 95% lower bound of 0.20 ng/kg. These values fall close to, but below, current estimates of human body burdens of 13 ng/kg, based on TCDD toxic equivalents. 相似文献
968.
969.
This study examined relationships among perceived stress, self-esteem, acculturation, and gender with the coping response of 472 Mexican American adolescents aged 14 to 16 years. Subjects were drawn from a predominantly Mexican American population located in the Lower Rio Grande Valley region of Texas. Data were collected through a self-report instrument consisting of perceived stress, acculturative status, self-esteem, and coping strategy scales. Subjects reported relatively high perceived stress levels, low acculturation, and moderate self-esteem scores with no significant gender differences. Analysis revealed self-esteem as most predictive of a more effective overall coping response. Results suggest Mexican American adolescents possessing high self-esteem are less likely to encounter damage to their sense of self when confronted with stressors, thus allowing for productive coping. 相似文献
970.
Nelis E Erdem S Tan E Löfgren A Ceuterick C De Jonghe P Van Broeckhoven C Timmerman V Topaloglu H 《Neuromuscular disorders : NMD》2002,12(9):869-873
Mutations in the myotubularin-related protein 2 gene on chromosome 11q22 are known to cause autosomal recessive Charcot-Marie-Tooth disease with irregularly folded myelin sheaths. We screened the coding region of the myotubularin-related protein 2 gene in a Turkish consanguineous Charcot-Marie-Tooth disease family compatible with linkage to chromosome 11q22. A homozygous cytosine to thymine missense mutation at nucleotide position 847, resulting in an amino acid substitution of arginine to tryptophan at codon 283, was detected in exon 9 of the MTMR2 gene. This is the second homozygous missense mutation associated with recessive Charcot-Marie-Tooth disease with focally folded myelin sheaths. 相似文献