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11.
Acute toxicity of the fungicide, captan, to juvenile rainbow trout was evaluated under static-renewal test condition. Actual concentrations of captan ranged from 0.05 to 1.00 mg/L. The concentrations of captan that killed 50% of the rainbow trout (3.11 ± 0.8 g) within 24 (24 h; LC50), 48, 72 and 96 h were 0.57 ± 0.09, 0.49 ± 0.10, 0.44 ± 0.11 and 0.38 ± 0.13 mg/L (95% confidence limits), respectively. None of the unexposed control fish died and the first fish died 6 h after exposure to captan (≥0.65 mg/L). Hypertrophy, separation of epithelium from lamellae, lamellar fusion, and epithelial cell necrosis were observed on captan exposed fish. Gills also had scattered areas of focal lamellar hyperplasia. Fish exposed to fungicide had inflammation and necrosis in liver, trunk kidney and spleen. In order, the most affected organs were gill, trunk kidney and liver.  相似文献   
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Background/aim Hepatitis B virus (HBV) vaccination rates are insufficient in high-risk patients worldwide. This study aimed to investigate the screening, immunization, and vaccination rates in three high-risk groups for HBV infection: allogeneic hematopoietic stem cell transplantation (AHSCT), renal transplantation (RT), and chronic hepatitis C (CHC) groups. Materials and methods The serological data of consecutive patients between 2014 and 2019 were reviewed using the hospital database. Results The HBV screening rates were 100.0%, 90.4%, and 82.4% in the AHSCT, CHC, and RT groups, respectively (p = 0.003). The immunization rates against HBV through either previous exposure or vaccination were 79.5%, 71.7%, and 46.5% in the AHSCT, RT, and CHC groups, respectively (p < 0.001). The HBV vaccination rate was significantly low in the CHC group (71.5%, 69.0%, 34.6% in the AHSCT, RT, and CHC groups, respectively, p < 0.001). If patients lost their immunity due to immunosuppressive therapy were accounted, the vaccination rates increased to 95.2% in the AHSCT group and 72.9% in the RT group. The rate of annual screening for HBV status was 97.9% in the AHSCT group, but it was only 23.9% in the RT group. Conclusion HBV screening and vaccination rates were significantly lower in the RT and CHC groups than in the AHSCT group.  相似文献   
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AIM: This prospective study aimed to investigate the diagnostic value of serum procalcitonin levels in children with acute pyelonephritis documented by Tc-dimercaptosuccinic acid (DMSA) scintigraphy. METHODS: We compared the symptoms and laboratory findings of fever, vomiting, abdominal/flank pain, leukocyte count, serum C-reactive protein and procalcitonin levels with the results of the DMSA scan obtained within the first 72 h after referral in children who were diagnosed as having acute pyelonephritis. Thirty-three children (31 female and two male) aged 1-11 years (mean 4.42 years) were enrolled in this prospective study. RESULTS: Twenty-one of 33 patients (64%) had positive DMSA scans. On the scans obtained after 6 months, five of 21 patients (23.8%) had renal scars. No correlation was found between clinical and laboratory parameters, alone or combined with each other, and positive DMSA scans. Serum procalcitonin levels were 0.767+/-0.64 and 1.23+/-1.17 ng . ml in children with normal and positive DMSA scans, respectively. The cut-off value for procalcitonin using receiver operating characteristic analysis was 0.9605 ng . ml, while sensitivity and specificity were 86.4% and 36.4%, respectively. However, if the cut-off value was chosen as 2 ng . ml, the sensitivity increased to 100% while specificity did not change markedly. CONCLUSION: The serum procalcitonin test, like other commonly used laboratory parameters, e.g. serum C-reactive protein and white blood cell count, was inadequate in distinguishing renal parenchymal involvement in acute febrile urinary tract infections.  相似文献   
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Bacillus anthracis infection can lead to necrosis in tissues and may manifest as a fatal disease in human beings. The authors present a patient with a large area of skin necrosis on the dorsum of the hand that was reconstructed with a reverse flow-through radial forearm flap, and they discuss the relevant literature. To the authors' knowledge, this is the first published report of such extensive necrosis resulting from anthrax limited to the extensor retinaculum of the hand.  相似文献   
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Our purpose was to elucidate why clinical studies have up to now failed to demonstrate a positive effect of TRH combined with glucocorticosteroids on fetal lung maturity. Morphological and biochemical lung maturation were determined by electron microscopy, choline incorporation, and surfactant-protein-A m-RNA synthesis in rat lung organoid cultures after exposure with a series of concentrations of dexamethasone, triiodothyronine, and dimethyl-isopropyl-thyronine. Thyroid hormones improved morphogenesis of lung histotypic structures but had a negative effect on surfactant synthesis whereas glucocorticosteroids had a positive effect on the surfactant synthesis but a negative effect on morphogenesis. The combination of both substances even had the most negative effect on morphogenesis. Since morphogenesis of lung histotypic structures is prerequisite for surfactant synthesis and secretion, we hypothesize that a sequential treatment of thyroid hormones to improve morphogenesis followed by the application of glucocorticosteroids might be an option to improve neonatal lung function.  相似文献   
18.

Background/Purpose

The aim of this study was to evaluate the effects of maternal nicotine exposure during gestation on injury severity of small intestine in the newborn rats subjected to hypoxia-reoxygenation and cold stress.

Methods

A total of 21 Sprague-Dawley pregnant rats were divided into 3 equal groups. The groups were labeled as group 1, control group; group 2, hypoxia-reoxygenation group; and group 3, nicotine-hypoxia-reoxygenation group. The rats of group 3 were exposed to nicotine via subcuticular injection for the last week of gestation (2 mg/kg/d). Newborn rats were collected immediately after birth to prevent suckling of maternal milk (40 rat pups in group 1, 43 rat pups in group 2, and 41 rat pups in group 3). Litters in groups 2 and 3 were stressed twice daily with asphyxia followed by cold (4°C for 10 minutes) stress to induce hypoxic intestinal injury which is relevant to human necrotizing enterocolitis. Breathing 100% CO2 for 10 minutes in a chamber followed by 10-minute 100% O2 breathing was the asphyxia model repeated twice daily. After hypoxia-reoxygenation and cold stress, newborn rats were returned to their mother's cages. This protocol was repeated for the following 2 days, and the rat pups were decapitated on the third day. Using this protocol of asphyxia and cold stress, all of neonatal rats developed clinical and pathological signs of hypoxia-induced intestinal injury. The entire gastrointestinal tract was removed and examined macroscopically. A 2-cm section of distal ileum from each animal was taken for histopathological and biochemical examinations. Histological changes in ileal architecture were scored and graded from 1 to 5. The remaining intestinal tissues of the animals were used for lipid peroxidation analysis.

Results

Typical signs of hypoxia-induced intestinal injury were observed in the 2 experimental groups (groups 2 and 3) macroscopically. There were more grades 3 and 4 injuries in group 3 (P < .05). The malondialdehyde levels were elevated in groups 2 and 3 (P < .001). The malondialdehyde levels of the group 3 were also significantly higher than group 2 (P < .01).

Conclusions

Maternal nicotine exposure during gestation results in higher grade histological injury in newborn rats subjected to hypoxia-reoxygenation and cold stress.  相似文献   
19.
The use of the Sheehan knee prosthesis extended from 1971 to 2002. It incorporated a semi-constrained hinge with intra-medullary stems cemented into the femur and tibia. While some authors have reported excellent short-term results, others have reported revision rates of up to 31% at 5–10 years. The aim of this study was to review the senior authors experience in revising these arthroplasties. We review 54 Sheehan total knee replacements and discuss the difficulties encountered during first and subsequent revisions and the often-complex reconstruction techniques used to overcome these.
Résumé Lutilisation de la prothèse de genou de type Sheehan sest étendue de 1971 à 2002. Elle comportait une charnière semi-contrainte avec des tiges intra-médullaires cimentées dans le fémur et le tibia. Tandis que dexcellents résultats à court terme ont été rapportés par quelques auteurs, un taux de révision jusquà 31% à 5–10 ans a été rapporté par dautres. Le but de cette étude était examiner lexpérience de lauteur senior dans la révision des prothèses de Sheehan. Nous avons examiné 54 prothèses et discutons les difficultés rencontrées pendant larthroplastie initiale et les révisions ultérieures ainsi que les techniques souvent complexes de reconstruction utilisées pour les mener à bien.
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