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41.
Summary Both transport and biotransformation processes for a series of pyrimidine nucleobases, ribonucleosides, 2-deoxyribonucleosides, and acetyl and 5-substituted derivatives of the cancerostatic agent araC were studied in the isolated everted rat jejunum with a continuous perfusion technique. Metabolic alterations during penetration were assessed by HPLC. 5-Halogeno and 5-deoxy derivatives of cytosine nucleosides exhibited higher transport rates and higher stability towards the deamination reaction than did unsubstituted derivatives. Octanol-buffer partition coefficients were estimated for the study compounds, and fragmental constants for the sugar moieties of nucleosides were assessed. With the present study compounds there was no correlation between lipophilicity and transport rate, as previously reported, but there was a correlation between lipophilicity and metabolic alteration of araC derivatives (r=0.99, n=5).  相似文献   
42.
Journal of Occupational Rehabilitation - Purpose We aimed to identify job accommodations that help persons with physical disabilities maintain or return to work and explore the barriers and...  相似文献   
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44.
Bulletin of Environmental Contamination and Toxicology - The application of Cu and CuO nanofertilizers in horticulture has been a promising strategy to promote plants’ growth. In our study,...  相似文献   
45.
Numerous cilia were found in the proximal convoluted tubules from a case of crescentic glomerulonephritis. The cilia exhibited the 9 + 2 pattern of organization characteristic of motile cilia. Microvilli were scanty or absent in heavily ciliated cells. The significance of renal cilia is discussed.  相似文献   
46.
Summary A new antireflux uretero-ileal reimplantation technique suitable for use with bladder substitutes is presented. This procedure entails creation of a serouslined extramural tunnel. Following detubularization of the bowel segment, the adjacent flaps are approximated by continuous 4/0 non-absorbable sutures 1.5 cm from the cut edges. The ureters are laid in the trough thus fashioned. Button-holes are created in the bowel flaps and a mucosa-to-mucosa uretero-ileal anastomosis is carried out. The mucosal edges of the flaps are then approximated by one layer of continuous 4/0 (PGA) suture resulting in closure of this artificial tunnel. The feasibility and functional outcome of this technique were experimentally investigated in 8 dogs. Follow-up was carried out up to 30 weeks. Assessment by intravenous urography and ascending studies showed that the procedure is an efficient method of providing an unobstructed unidirectional flow of urine.  相似文献   
47.
Non-small cell lung cancer (NSCLC) is one of the most common types of cancer in the world and has a 5-year survival rate of ~20%. Immunotherapies have shown promising results leading to durable responses, however, they are only effective for a subset of patients. To determine the best therapeutic approach, a thorough and in-depth profiling of the tumour microenvironment (TME) is required. The TME is a complex network of cell types that form an interconnected network, promoting tumour cell initiation, growth and dissemination. The stroma, immune cells and endothelial cells that comprise the TME generate a plethora of cytotoxic or cytoprotective signalling pathways. In this review, we discuss immunotherapeutic targets in NSCLC tumours and how the TME may influence patients' response to immunotherapy.  相似文献   
48.
Correlation between fungi isolated from burn wounds and burn care units   总被引:2,自引:0,他引:2  
A comparison was made prospectively between fungal isolates from patients and burn care units. Aspergillus niger was the most frequent isolate in both patients and burn care units whereas Ulocladium was the commonest isolate in the control group. Aspergillus terreus, Penicillium and Zygomycetes, which were recovered from burned patients, were also found more frequently in the burn care units than in the control group (other areas in the hospital). These findings indicate a potential risk of fungal infection which can be acquired from the immediate surroundings of patients in burn care units. Periodical burn ward decontamination is therefore recommended.  相似文献   
49.
The hepatoprotective and antimutagenic effects of the rosemary essential oil and the ethanolic extract were investigated using carbon tetrachloride and cyclophosphamide as hepatotoxic and mutagenic compounds, respectively. Our results revealed that i.g. administration of the rosemary ethanolic extract (0.15 g/100 g BW) to rats for 3 weeks produced the most pronounced hepatoprotective effect compared to silymarin (reference compound) due to the amelioration of most of the studied serum and liver parameters and confirmed by histopathological examination of the liver tissue. Pretreatment of mice for 7 days with the rosemary essential oil (1.1 mg/g BW) followed by i.p. injection with cyclophosphamide reduced significantly the induced mitodepression in the bone marrow cells of the animals. The potential hepatoprotective and antimutagenic activities of the rosemary ethanolic extract and essential oil, respectively, are attributed to the presence of a relatively high percentage of phenolic compounds with high antioxidant activity (according to our chemical studies).  相似文献   
50.
OBJECTIVE: Prediction of neurologic outcome is difficult in neonates with acute nervous system injury. Previous studies using proton magnetic resonance spectroscopy ((1)H-MRS) have been used to predict short-term neurologic outcome in neonates with a variety of neurologic insults. We were interested in determining the effectiveness of combining clinical evaluation and spectroscopy obtained at the time of injury in predicting neurologic outcome at 24 months. STUDY DESIGN: We studied 33 neonates with acute central nervous system injury, 5.8+/-3.7 days of injury, owing to hypoxic-ischemic encephalopathy. Neonates were assessed using clinical variables (initial arterial pH, initial blood glucose, Sarnat score, electroencephalography) and spectroscopy (NAA/Cho, NAA/Cre, Cho/Cre, and lactate). Neonates were divided into two outcome groups: good/moderate and poor. Differences between the groups were assessed using chi(2) and t-test analyses. We analyzed the best predictors of outcome using discriminant analysis and calculated sensitivity, specificity, positive, and negative predictive values for each variable independently and in combination. RESULTS: There were significant differences between the good/moderate and poor outcome for the Sarnat score, EEG, lactate, and NAA/Cho. Spectroscopy combined with clinical variables improved sensitivity, but not specificity for predicting outcome. The presence of lactate had the best individual predictive value. Combination of the clinical with the MRS variables had the highest predictive value. CONCLUSION: Proton magnetic resonance spectroscopy done early after injury improves the ability to predict neurologic outcome at 24 months of age.  相似文献   
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