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排序方式: 共有1476条查询结果,搜索用时 31 毫秒
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Tu'meh SS; Tracy DA; Wynne J; Konstam MA; Kozlowski JF; Neumann AL; Holman BL 《Radiology》1982,145(2):463-466
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%. 相似文献
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Postembolic colonic infarction 总被引:12,自引:0,他引:12
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Pac S McMahon K Ripple M Reidy K Ziegler P Myers E 《Journal of the American Dietetic Association》2004,104(3):455-467
This paper outlines the three different methods used to develop the Start Healthy Feeding Guidelines for Infants and Toddlers. The resulting consensus on each guideline area is given in the accompanying paper (3), which should prove useful for both parents and professionals.11112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180 相似文献
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Mono(2-ethyl-5-hydroxyhexyl) phthalate and mono-(2-ethyl-5-oxohexyl) phthalate as biomarkers for human exposure assessment to di-(2-ethylhexyl) phthalate 总被引:11,自引:0,他引:11
Kato K Silva MJ Reidy JA Hurtz D Malek NA Needham LL Nakazawa H Barr DB Calafat AM 《Environmental health perspectives》2004,112(3):327-330
Exposure to di-(2-ethylhexyl) phthalate (DEHP) is prevalent based on the measurement of its hydrolytic metabolite mono-(2-ethylhexyl) phthalate (MEHP) in the urine of 78% of the general U.S. population studied in the 1999-2000 National Health and Nutrition Examination Survey (NHANES). However, despite the high level of production and use of DEHP, the urinary MEHP levels in the NHANES samples were lower than the monoester metabolites of phthalates less commonly used than DEHP, suggesting metabolic differences between phthalates. We measured MEHP and two oxidative DEHP metabolites, mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) to verify whether these other metabolites account for a greater proportion of DEHP metabolic products in 127 paired human urine and serum samples. We found that the urinary levels of MEHHP and MEOHP were 10-fold higher than levels of MEHP; concentrations of urinary MEOHP and MEHHP were strongly correlated (r = 0.928). We also found that the serum levels of MEOHP and MEHHP were comparatively lower than those in urine. Furthermore, the glucuronide-bound conjugates of the oxidative metabolites were the predominant form in both urine and serum. MEOHP and MEHHP cannot be formed by serum enzymes from the hydrolysis of any contamination from DEHP potentially introduced during blood collection and storage. Therefore, concentrations of MEHHP and MEOHP in serum may be a more selective measure of DEHP exposure than is MEHP. However, additional data on the absorption, distribution, metabolism, and elimination of these oxidative metabolites are needed to completely understand the extent of DEHP exposure from the serum concentrations of oxidative DEHP metabolites. 相似文献
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OBJECTIVE(S): The objective was to determine whether there were changes in the pattern and nature of hospitalizations during the last year that could be used in the assessment of whether chemotherapy should be continued. METHODS: Retrospective data were collected from patients who died from ovarian cancer between 1/2000 and 12/2001. Charts from four hospitals were reviewed to abstract chemotherapy, reason for hospitalization, and the incidence of three significant clinical events (bowel obstruction, pleural effusion requiring thoracentesis, and abdominal ascites requiring paracentesis). Data were analyzed in 3-month intervals. RESULTS: Sixty-two patient charts were reviewed. Quarterly admissions increased linearly over the year (7, 18, 27, and 47, P < 0.0001). Hospitalizations for ascites, bowel obstruction, and pleural effusion began increasing around 6 months preceding death. Twenty-two patients did not receive chemotherapy during the last 3 months. Of the 40 patients receiving chemotherapy in the last 3 months, over half were not hospitalized during the period 4-6 months before death, and a further 20% were hospitalized for nonsignificant clinical events. Approximately one-quarter of the patients, however, continued to receive chemotherapy following hospitalization for a significant clinical event. CONCLUSION(S): There were significant changes in the pattern and nature of hospitalization during the last 6 months that included hospitalizations for bowel obstruction, pleural effusion, or ascites. The occurrence of these events suggests that further chemotherapy should be realistically evaluated with the patient, which may reduce the number of patients who receive chemotherapy during their last few months of life. 相似文献
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Kato K Silva MJ Brock JW Reidy JA Malek NA Hodge CC Nakazawa H Needham LL Barr DB 《Journal of analytical toxicology》2003,27(5):284-289
We developed a highly sensitive method for the quantitative detection of nine phthalate ester metabolites in human serum. This method requires denaturation of the serum enzymes immediately after blood collection to avoid the hydrolysis of the contaminant diester parent compounds introduced during blood collection and storage. Before analysis, the samples were subjected to an enzymatic deconjugation to hydrolyze the glucuronidated phthalate monoesters and a solid-phase extraction to isolate the monoesters from other serum components. The extracts were analyzed using reversed-phase high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. The limits of detection of all nine phthalate monoesters in serum were in the low nanogram-per-milliliter range (0.6-1.3 ng/mL). Stable isotope-labeled internal standards for all analytes were used to improve precision and for recovery corrections. This highly selective method permits the analysis of phthalate monoesters without interferences resulting from the hydrolysis of the ubiquitous contaminant phthalate diesters by serum enzymes. In addition, it allows the direct measurement of the active phthalate monoester metabolites reportedly responsible for the reproductive and developmental toxicity of certain phthalates. 相似文献