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61.
In the present study 350 school boys and 350 school girls in the age group of 5 to 12 yr were studied. It was observed that
there is parallel progressive increase in physical growth and pulmonary function in this age group. There was positive significant
correlation of FEV1 with height and weight. 相似文献
62.
We present the first reported case of a schwannoma of the seminal vesicle that occurred in a 48-year-old man who presented with right lower quadrant abdominal pain. Computed tomography scan and magnetic resonance imaging revealed a mass in the patient's right seminal vesicle. The patient was also found to have a rising prostate-specific antigen level and underwent a transrectal ultrasound-guided biopsy of the prostate and seminal vesicles, which revealed prostate cancer and schwannoma of the seminal vesicle, respectively. Radical prostatectomy with en bloc removal of the seminal vesicle mass was performed and the patient has been free of disease 24 months postoperatively. 相似文献
63.
Lead induced oxidative damage and its response to combined administration of alpha-lipoic acid and succimers in rats 总被引:2,自引:0,他引:2
Alpha-lipoic acid (LA) has been reported to be highly effective in improving the thiol capacity of the cells and in reducing lead induced oxidative stress. These results suggested its possible role as a therapeutic intervention of lead poisoning in combination with a chelator. We investigated the effects of LA, either alone or when administered in combination with succimer (meso 2,3-dimercaptosuccinic acid; DMSA or one of its analogue monoisoamyl DMSA), in influencing the lead induced alterations in haem synthesis pathway, hepatic, renal and brain oxidative stress and lead concentration from blood and soft tissues. The results suggest a significant lead induced inhibition of delta-aminolevulinic acid dehydratase (ALAD), reduction in glutathione (GSH) and an increased zinc protoporphyrin (ZPP) level in blood, indicating altered heme synthesis pathway. Both the thiol chelators were able to increase blood ALAD activity and GSH level towards normal. The most prominent effect on blood ALAD activity was however observed when monoisoamyl DMSA (MiADMSA) was co-administered with LA. Lead exposure produced significant depletion of hepatic GSH, while, oxidized glutahione (GSSG), thiobarbituric acid reactive substances (TBARS) and catalase activity increased significantly, suggesting hepatic oxidative stress. All the treatments were able to increase hepatic GSH and reduce GSSG levels, while, TBARS level reduced significantly in animals administered LA and MiADMSA, individually or in combination. Lead induced increase in renal GSSG, TBARS levels and catalase activity, were effectively reduced by LA, while, the two chelators when administered alone were effective only in reducing GSSG and catalase activity. The most prominent beneficial effects, however, were observed in animals treated concomitantly with LA and one of the chelators (DMSA or MiADMSA). Brain GSH and GSSG levels decreased moderately while superoxide dismutase (SOD) activity remained statistically unaltered on lead exposure. Brain catalase activity, on the other hand, increased significantly. Administration of LA was effective in reducing these alterations in the brain, however, the best effects were achieved in animals co-administered LA and one of the thiol chelators. The results point to a significant beneficial role of LA in the recovery of altered biochemical variables both during monotherapy and when given in combination with succimer. It however, showed no chelating properties in decreasing lead burden from blood, liver and kidneys except for a significantly more pronounced decrease in brain lead concentration in animals administered LA plus thiol chelators, compared to the effects of chelating agents alone. This is an interesting and notable observation, which requires further exploration. The results thus provide evidence of an encouraging role of LA when given in combination with a thiol chelator in the therapeutic intervention of lead poisoning, particularly in reducing the oxidative stress and brain lead concentration. 相似文献
64.
Male rats were given 50 mg/kg molybdenum (Mo; as sodium molybdate) in drinking water for eight consecutive doses. The feeding of Mo was associated with an increased concentration of Mo in body tissues. The highest concentrations of metal were found in the kidney while it was least in blood cells. The accumulation was considered to be significant. 相似文献
65.
Paul BN Prakash A Kumar S Yadav AK Mani U Saxena AK Sahu AP Lal K Dutta KK 《Biomedical and environmental sciences : BES》2002,15(3):215-222
Objective To investigate the pharmacological effect of Nyctanthes arbortristis (NAT) leaf extract in the prevention of lung injury induced by silica particles. Method Lung injury was induced in Swiss mice through inhalation exposure to silica particles (<5μ) using a Flow Past Nose Only Inhalation Chamber at the rate of -10 mg/m3 respirable mass for 5 h. Lung bronchoalveolar lavage (BAL) fluid collected between 48 and 72 h was subjected to protein profiling by electrophoresis and cytokine evaluation by solid phase sandwich ELISA. Lung histopathology was performed to evaluate lung injury. Results Inhalation of silica increased the level of tumor necrosis factor-α(TNF-α), and of the 66 and 63 kDa peptides in the BAL fluid in comparison to sham-treated control. Pre-treatment of silica exposed mice with NAT leaf extract significantly prevented the accumulation of TNF-α in the BAL fluid, but the 66 and 63 kDa peptides remained unchanged. The extract was also effective in the prevention of silica-induced early fibrogenic reactions like congestion, edema and infiltration of nucleated cells in the interstitial alveolar spaces, and thickening of alveolar septa in mouse lung. Conclusion NAT leaf extract helps in bypassing silica induced initial lung injury in mice. 相似文献
66.
Ventricular volume change in childhood 总被引:3,自引:0,他引:3
OBJECT: The aim of this study was to construct a model of age-related changes in ventricular volume in a group of normal children ages 1 month to 15 years, which could be used for comparative studies of cerebrospinal fluid circulation disorders and cerebral atrophy developmental syndromes. METHODS: A magnetic resonance imaging-based segmentation technique was used to measure ventricular volumes in normal children; each volume was then plotted against the child's age. In addition, intracranial volumes were measured and the ratio of ventricular to intracranial volume was calculated and plotted against age. The study group included 71 normal children, 39 boys and 32 girls, whose ages ranged from 1 month to 15.3 years (mean 84.9 months, median 79 months). The mean ventricular volume was 21.3 cm3 for the whole group, 22.7 cm3 in boys and 19.6 cm3 in girls (p = 0.062, according to t-tests). The mean ventricular volume at 12 months for the whole group was 17 cm3 (20 cm3 in boys and 15 cm3 in girls), representing 65% of the volume achieved by 15 years of age (87% in boys and 53% in girls). The volume increased by a factor of 1.53, to 26 cm3 (23 cm3 in males and 28 cm3 in females, increase factors of 1.15 and 1.86, respectively) at 15 years of age. The change in ventricular volume with age is not linear, but follows a segmental pattern. These age periods were defined as: 0 to 3, 4 to 6, 7 to 10, and 11 to 16 years. A statistical difference based on sex was only demonstrated in the first 6 years of life. The mean ventricular volume for the first 6-year period was 22.4 cm3 in boys and 15.7 cm3 in girls, and the difference was significant for the two sexes (linear regression analysis for age and sex, significant according to analysis of variance regression at 0.007, p = 0.108 for age, p = 0.012 for sex). Thereafter, there was no significant difference in ventricular volume between boys and girls with further growth. The ratio of ventricular volume to intracranial volume was 0.0175 for the whole group, 0.017 in boys and 0.018 in girls (p = 0.272, according to t-tests). At 12 months of age the ratio was 0.019; it stabilized to 0.015 at 8 years of age, and increased to 0.018 at 15 years of age. No statistical difference based on sex was demonstrated with growth. CONCLUSIONS: The ventricular volume in normal children increases with age by a factor of 1.5; the increase is in a nonlinear segmental pattern. Boys have significantly higher ventricular volumes only in the first 6 years of life. The ventricular/intracranial volume ratio remains stable throughout childhood. 相似文献
67.
In many biomedical experiments one may often encounter bivariate data which are component-wise ordinal. The data set of the ophthalmologic experiment of the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) is an example of such data. Several authors considered the analysis of such data from different viewpoints. The present work reviews the existing literature based on the WESDR data and on the basis of some latent variables provide the technique for analysing such data more easily in a Bayesian framework. Computation supports the methodology to a great extent. A comparison between our approach and the likelihood based approach considered by Kim has also been made. 相似文献
68.
The soil receives enormous quantities of pesticides and PCBs as a waste product each year due to their wide application. The degradation and eventual fate of these chemicals in the soil largely determine ultimate environmental impact. A survey of an abandoned landfill site has been conducted in a fast developing industrial city Nagpur (India) to assess the degree of environmental contamination with PCBs. The purpose was to determine if any of the mixture of PCBs, Aroclor 1254 and Aroclor 1260 are retained in the compost amended soil of the site despite atmospheric losses possible due the peak summer (100-117 degrees F) in the city. The accuracy and precision for Aroclor 1254 and Aroclor 1260 determinations in the soil samples have been calculated as 76.5 and +/- 0.92 and 83.3 and +/- 1.13 respectively. The samples analysis showed the presence of Aroclor 1254 and Aroclor 1254 and Aroclor 1260 up to the levels of 0.55 and 0.80 mg/g respectively. The maximum total PCBs on dry weight basis are found as 1.2 mg/g. 相似文献
69.
70.
The role of preservatives in the conjunctival toxicity of subconjunctival gentamicin injection. 总被引:2,自引:0,他引:2
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Subconjunctival gentamicin was identified as the cause of conjunctival chemosis and capillary closure in a recent study conducted in this department. The gentamicin preparation used in the study contained preservatives. The current prospective study was set up to investigate the role of preservatives in the conjunctival toxicity of subconjunctival gentamicin. Seventy five patients undergoing cataract surgery were enrolled in the study. They were split into three groups of 25 each. Group A patients were given a subconjunctival injection of a preservative-free aqueous solution of gentamicin at the end of the cataract procedure. Group B patients were given a subconjunctival injection of gentamicin containing sodium metabisulphite and disodium edetate as preservatives at the end of the cataract procedure. Group C was the control group where patients were not given any subconjunctival injection. The incidence of severity of conjunctival chemosis were observed in the three groups. The difference between groups A and B patients who received preservative-free gentamicin and gentamicin with preservatives respectively was significant (p < 0.02). 相似文献