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Abstract: Ambient air was monitored for pesticides at four sites in Coffs Harbour, a coastal town (population about 50 000) surrounded by banana plantations. Air was sampled continuously for five consecutive months during the peak agricultural spraying period using vacuum pumps set to sample one litre per minute through ORBO-42 adsorption tubes. Six pesticides were detected: three organochlorines and three organophosphates. The most commonly detected pesticide (14 per cent of all samples) was chlor-pyrifos (maximum detected level 208.0 ng/m3, mean 3.6 ng/m3). Heptachlor was detected in 7.1 per cent of all samples (maximum detected level 133 ng/m3, mean 2.7 ng/m3). Other pesticides were only rarely detected. The only pesticide applied by air in the district (propiconazole) was not detected. If international health guidelines are used as a yardstick, these levels of exposure appear unlikely to present an appreciable health risk. Chlorpyrifos detection was associated with low wind speed (P = 0.012) and high temperature (P = 0.015), and detection at one site was associated with detection at another (P < 0.001). Chlorpyrifos detection was also associated with domestic applications within the town area as reported by pesticide applicators (P = 0.045). Peak agricultural use of chlorpyrifos did not coincide with peak detection periods. None of the detected organochlorines is registered for agricultural use, although at the time, heptachlor was permitted for use as a domestic termiticide. Even in a semirural town with nearby widespread use of agricultural chemicals, community exposures to pesticides in ambient air may largely relate to their nonagricultural use.  相似文献   
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We report a case of renal transplant ureteral obstruction caused by a cyclosporine-associated B cell lymphoproliferative disorder. The interaction of cyclosporine with Epstein-Barr virus infections and the predisposition towards B cell lymphoproliferative disorders are reviewed. The characterization of these tumors by deoxyribonucleic acid hybridization studies and a review of the clinical experience treating these disorders also are presented.  相似文献   
14.
Fractures of the epiphyseal plate are considered rare when compared with the more prevalent injuries found in competitive sports, but the complications associated with this type of trauma are a major concern. The factors affecting the success or failure of healing include the severity of injury, patient age, and the type and expedience of treatment. This case study examines the clinical presentation and treatment of a 15-yr-old high school football player who sustained a displaced, distal femoral epiphyseal Salter II fracture. Primary treatment consisted of nonmanipulative, nonweight bearing knee immobilization. The treatment resulted in malunion, pain, decreased range of motion and physical deformity; therefore, the patient sought a second opinion. On physical exam, the displacement and rotational deformity of the fracture site were unacceptable. The fracture was treated 20 days post-injury via open reduction with internal fixation. On follow-up, the athlete demonstrated radiographic healing, normal physical exam, and no significant leg length discrepancy or deformity. The athlete successfully returned to full competitive sport activity.  相似文献   
15.
Treatment of rat pheochromocytoma PC18 cells (a variant subclone of PC12 cells) with forskolin produced increased activity and phosphorylation of tyrosine hydroxylase. In contrast, treatment of the PC18 cells with 56 mM K+, A23187, phorbol-12-myristate-13-acetate (PMA) or phorbol-12,13-dibutyrate (PDB) did not affect the activity and only slightly increased the phosphorylation of tyrosine hydroxylase. None of the treatments except forskolin increased cyclic AMP levels in PC18 cells. Furthermore, 45Ca2+ uptake into PC18 cells was not affected by 56 mM K+, PDB or forskolin; however, A23187 increased 45Ca2+ uptake 4-fold over basal uptake. Nevertheless, no activation and little increase in phosphorylation of tyrosine hydroxylase was observed in PC18 cells treated with A23187. When tyrosine hydroxylase levels in PC18 cells were elevated by treatment with dexamethasone, activation of tyrosine hydroxylase by 56 mM K+, PDB or A23187 was still not observed. Both purified Ca2+/calmodulin-dependent protein kinase and cyclic AMP-dependent protein kinase catalyzed the phosphorylation of tyrosine hydroxylase purified from PC18 cells in vitro. Furthermore, crude cell extracts from PC12 cells and PC18 cells possessed Ca2+/calmodulin-dependent protein kinase activity that catalyzed the phosphorylation of purified tyrosine hydroxylase. These results suggest that tyrosine hydroxylase activity in PC18 cells is regulated by a cyclic AMP-dependent mechanism. However, due to a number of abnormalities the Ca(2+)-dependent mechanisms do not result in the activation of tyrosine hydroxylase and only slightly increase the phosphorylation of the enzyme in PC18 cells.  相似文献   
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Abstract: Hydantoin is an anticonvulsant drug with several side effects. A teralogenic potential has been suggested. The fetal hydantoin syndrome is an entity that consists of a broad range of morphologic and developmental disorders in children born of epileptic mothers exposed to hydantoin during pregnancy. We treated a girl in whom onychopathy was a monosymptomatic or mild form of this syndrome.  相似文献   
18.
The incidence and patterns of and factors associated with inappropriate antibiotic use were studied in a tertiary care center in Thailand. The incidence of inappropriate antibiotic use was 25%. Admission to the surgical department (adjusted odds ratio, 2.0; P=.02) and to the obstetrics and gynecology department (adjusted odds ratio, 2.0; P=.03) were associated with inappropriate antibiotic use, whereas consultation with an infectious diseases specialist was protective against inappropriate antibiotic use (adjusted odds ratio, 0.15; P=.01).  相似文献   
19.
OBJECTIVE: Interstitial brachytherapy is becoming an accepted treatment option for lung cancer patients for whom surgery poses a high risk. Robotic surgery has the potential to deliver brachytherapy seeds into tumors while keeping surgeons at a safe distance from the radioactive source. Our aim was to compare the accuracy, number of attempts, and time needed to place seeds next to a target when using a manual technique, video-assisted thoracoscopic surgery (VATS), and the ZEUS robot for minimally invasive surgery (MIS). METHODS: A brachytherapy seed injector was developed and attached to one of the ZEUS robotic arms. Four subjects each inserted inactive dummy brachytherapy seeds into clear agar-gelatin cubes containing a 1.6-mm stainless steel ball target. Two orthogonal radiographs were taken of each agar cube, and the corresponding distances were measured in triplicate using ImageJ processing software. The mean distance between the center of each seed and the corresponding target was calculated using the Pythagorean theorem. Comparisons were made using analysis of variance, t-tests, and Kruskal-Wallis tests, as appropriate. RESULTS: A total of 384 tests (128 for each technique) were performed. The median accuracies for the manual technique, VATS, and ZEUS were 1.8 mm (range: 0.9-6.7 mm), 2.4 mm (range: 1.0-11.3 mm), and 3.6 mm (range: 1.3-16.7 mm), respectively (p < 0.01). The median numbers of attempts for the manual technique, VATS, and ZEUS were 1 (range: 1-5), 4 (range: 1-14), and 3 (range: 1-20), respectively (p < 0.01). The median times for the manual technique, VATS, and ZEUS were 3.0 s (range: 1-43 s), 86.5 s (range: 6-372 s), and 64.5 s (range: 5-356 s), respectively (p < 0.01). CONCLUSIONS: The manual technique is the most accurate, least traumatic, and fastest method of inserting seeds into tumors. The ZEUS robotic platform was able to place seeds beside a target within a clinically acceptable distance, with an acceptable amount of trauma and time required. It achieved results equal to or better than those obtained with VATS.  相似文献   
20.
OBJECTIVE: To characterize risk factors for surgical-site infection after spinal surgery. DESIGN: A case-control study. SETTING: A 113-bed community hospital. METHOD: From January 1998 through June 2000, the incidence of surgical-site infection in patients undergoing laminectomy, spinal fusion surgery, or both increased at community hospital A. We compared 13 patients who acquired surgical-site infections after laminectomy, spinal fusion surgery, or both with 47 patients who were operated on during the same time period but did not acquire a surgical-site infection. Information collected included demographics, risk factors, personnel involved in the operations, length of hospital stay, and hospital costs. RESULTS: Of 13 case-patients, 9 (69%) were obese, 9 (69%) had spinal compression, 5 (38.5%) had a history of tobacco use, and 4 (31%) had diabetes. Oxacillin-sensitive Staphylococcus aureus (6 of 13; 46%) was the most common organism isolated. Significant risk factors for postoperative spinal surgical-site infection were dural tear during the surgical procedure and the use of glue to cement the dural patch (3 of 13 [23%] vs 1 of 47 [2.1%]; P = .02) and American Society of Anesthesiologists risk class of 3 or more (6 of 13 [46.2%] vs 7 of 47 [15%]; P = .02). Case-patients were more likely to have prolonged length of stay (median, 16 vs 4 days; P< .001). The average excess length of stay was 11 days and the excess cost per case was $12,477. CONCLUSION: Dural tear and the use of glue should be evaluated as potential risk factors for spinal surgical-site infection. Systematic observation for potential lapses in sterile technique and surgical processes that may increase the risk of infection may help prevent spinal surgical-site infection.  相似文献   
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