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991.
Giuriati C Cristofori MC Gorni A Abballe F 《Annali dell'Istituto superiore di sanità》2003,39(2):223-228
In this work, specific topics will be covered in order to verify an effective, routine application of ion chromatography as a suitable and approved technique for emission monitoring in the determination of HF, HCl, NOx and SOx on stationary emission. A review of the analytical methods as proposed by recent updates in Italian environmental law and the problems encountered in the application of this method, such us the interference due to high level of carbonate, high hydroxides concentration particularly on SOx and NOx absorbing solution, are considered in the present work. The sample treatments before the IC analysis, this to reduce the matrix interference due to the strong basic solutions used to monitor different stationary emissions, are also examined. Some modifications in sampling are explored to find more suitable conditions for the IC analysis. 相似文献
992.
Muti P Awad AB Schünemann H Fink CS Hovey K Freudenheim JL Wu YW Bellati C Pala V Berrino F 《The Journal of nutrition》2003,133(12):4252-4255
Plant sterols or phytosterols are common components of plant foods, especially plant oils, seeds and nuts, cereals and legumes. The most common phytosterols are campesterol, beta-sitosterol and stigmasterol. Phytosterols have anticarcinogenic properties. Previous studies have suggested that populations with low breast cancer incidence often consume diets high in phytosterols. The present study evaluated whether consumption of a plant food-based diet, low in animal fat, may increase serum phytosterol levels in postmenopausal women. One hundred and four women volunteers were randomized to dietary intervention or control groups. The dietary intervention included intensive dietary counseling to replace animal products with plant-based foods. Subjects in the dietary intervention group participated twice a week for 18 wk in workshops about the preparation and consumption of a plant food-based diet. The absolute change in serum total phytosterol concentration was greater in the dietary intervention group than in the control group. The percent change tended to differ between groups (P = 0.06). However, only for beta-sitosterol did the absolute and percent changes within a group differ significantly between groups (P = 0.0017). The decrease in serum total cholesterol in the dietary intervention group (-14%) was greater than that in the control group (-4%; P = 0.0005). The results of this study show that circulating levels of phytosterols can be affected by dietary modification. These findings indicate that phytosterols, in particular beta-sitosterol, can be used as biomarkers of exposure in observational studies or as compliance indicators in dietary intervention studies of cancer prevention. 相似文献
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Preoperative, single-fraction irradiation for prophylaxis of heterotopic ossification after total hip arthroplasty 总被引:1,自引:1,他引:0
Lonardi F Gioga G Coeli M Ruffo P Agus G Pizzoli A Campostrini F 《International orthopaedics》2001,25(6):371-374
We gave a single fraction of 750 cGy preoperatively (within 16 h of surgery) to 143 patients prior to total hip arthroplasty. The patients were evaluated for heterotopic ossification at 1, 3 and 6 months. The preoperative radiation did not affect the surgical procedure. After a median follow-up of 12 (6-24) months we encountered six patients with heterotopic ossifications of Brooker grade I-II. Potential late risks from ionising radiation should be considered when treating younger patients. 相似文献
995.
The Problem of the Accuracy of Intraoperative Examination of Axillary Sentinel Nodes in Breast Cancer 总被引:7,自引:0,他引:7
Stefano Zurrida MD Giovanni Mazzarol MD Viviana Galimberti MD Giuseppe Renne MD Fabio Bassi MD Franco Iafrate MD Giuseppe Viale MD FRCPath 《Annals of surgical oncology》2001,8(10):817-820
Background: Sentinel node SN biopsy has become accepted as a reliable method of predicting the state of the axilla in breast cancer. The key issue, however, is the accuracy of the pathological evaluation of the biopsied node, which should be done intraoperatively whenever possible.Methods: In our initial experience on 192 patients using a conventional intraoperative frozen section method, the false-negative rate was 6.3%, and the negative predictive value was 93.7%. We devised a new and exhaustive intraoperative method, requiring about 40 minutes, in which pairs of sections are taken every 50 for the first 15 sections and every 100 thereafter, sampling the entire node. Sentinel node metastases were found in 143 of the 376 T1N0 cases examined 38%.Results: Metastases were always identified on hematoxylin and eosin sections, although in 4% of cases, cytokeratin immunostaining on adjacent sections was useful for confirming malignancy. In 233 patients the SNs were disease-free; of these patients, 222 had metastasis-free axillary nodes, and 11 4.7% had another metastatic node.Conclusion: Extensive intraoperative examination of frozen sentinel nodes correctly predicts an uninvolved axilla in 95.3% of cases negative predictive value. This method is, therefore, suitable for identifying patients in whom axillary dissection can be avoided. 相似文献
996.
Machado PG Garcia C Felipe CR Garcia R Franco M Delcelo R Silva HT Medina JO 《Transplantation proceedings》2001,33(1-2):1074-1075
997.
Franco RM Rocha-Eberhardt R Cantusio Neto R 《Revista do Instituto de Medicina Tropical de S?o Paulo》2001,43(2):109-111
Cryptosporidium parvum and Giardia duodenalis are waterborne parasites that have caused several outbreaks of gastrointestinal disease associated with drinking water. Due to the lack of studies about the occurrence of these protozoa in water in the Southeast of Brazil, an investigation was conducted to verify the presence of cysts and oocysts in superficial raw water of the Atibaia River. The water samples were submitted to membrane filtration (3.0 microm) and elution was processed by (1) scraping and rinsing of membrane (RM method) and (2) acetone-dissolution (ADM method). Microbiologic and chemical parameters were analyzed. Aliquots of the pellets were examined by immunofluorescence (Merifluor, Meridian Diagnostics, Cincinnati, Ohio). All water samples were positive for Cryptosporidium and Giardia, in spite of the high turbidity. Higher recovery rates occurred in samples treated by the RM method than by the ADM technique. The goal for future work is the assessment of viability of cysts and oocysts to determine the public health significance of this finding. 相似文献
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