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We have reported earlier that Aspergillus fumigatus is inhibited in vitro by Candida albicans which also interferes in its isolation from sputum experimentally seeded with predetermined graded inocula of the two fungi. It was further shown that this interference was neutralized by employing peptone glucose agar with incorporation of fluconazole which is more inhibitory to C. albicans than to A. fumigatus. This communication embodies the results of evaluation of peptone glucose fluconazole agar (PGFA) as a selective culture medium for rapid and enhanced isolation of A. fumigatus from sputum of patients clinically suspected of aspergillosis with C. albicans colonization in the respiratory tract. Of the 23 sputum specimens and one broncho-alveolar lavage collected from 15 suspected aspergillosis patients, A. fumigatus was isolated from all (100%) on PGFA as against only 19 specimens (79%) that proved to be positive on the control PGA medium (P<0.05). The greater efficacy of PGFA than that of PGA was further evident from the 2-fold higher A. fumigatus mean colony count (8.2+/-1.87) on the former medium than on the latter (3.7+/-1.00), and this difference was found to be statistically significant (P<0.05). Besides, A. fumigatus colonies were macroscopically recognizable within 2-3 days on PGFA at 28 degrees C in strong contrast to 5-7 days required on PGA. Based upon these observations, PGFA is recommended for wider application as a selective medium for rapid and enhanced recovery of A. fumigatus from sputum of patients clinically suspected of aspergillosis with C. albicans colonization in their respiratory tract.  相似文献   
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This brief review provides an overview of this topic; it is not a critical review. Polydrug use is a poorly defined concept; it is taken here to mean the simultaneous use of more than one drug. Data on polydrug use is seldom systematically collected, and the use of alcohol and tobacco in combination with illegal drugs is frequently overlooked. If alcohol and tobacco are included, most users are polydrug users, since these drugs are used by most users of illegal drugs, and many people with alcohol problems also use illegal drugs. Polydrug use has increased; drug availability, cultural context and the 'normalization' of drug use are important factors. Gender and racial differences are observed in the prevalence of polydrug use. Implications for drug prevention include the importance of targeting multiple substance use rather than single substances. Aiming prevention campaigns at younger people and focusing on 'gateway' drugs might be more effective. But polydrug users are diverse, and a variety of strategies (aimed at different types of polydrug users) are necessary. Implications for treatment include the evidence of the greater difficulty that polydrug users have in quitting; they may therefore require additional help. A fuller, systematic, review is required; it is expected that this would recommend the commissioning of additional research on this poorly understood phenomenon.  相似文献   
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Glial fibrillary acidic protein (GFAP) is the principal intermediate filament protein found in mature astrocytes. Although the exact function of GFAP is poorly understood, it is presumed to stabilize the astrocyte’s cytoskeleton and help in maintaining cell shape. Previous studies from our laboratory have shown that when astrocytes were cocultured with primary Schwann cells (pSCs), astrocytes became hypertrophied and fibrous with intensely positive GFAP staining and segregated Schwann cells (SCs) into pockets. In order to understand the functional role of GFAP in this already established astrocyte-SC coculture model, we generated GFAP-negative cell lines from a GFAP-positive astrocytoma cell line and cocultured both the cell lines with pSCs. Our studies demonstrate that the GFAP-positive cell line put out processes toward the SCs, whereas the GFAP-negative cells did not form processes and the majority of the cells remained round. The most significant and interesting finding of this study, however, is the formation of elaborate processes by SCs when grown in coculture with the astrocytoma cells, unlike SCs cultured alone, which showed their typical bipolar spindle-shaped morphology. The extent of processes did not seem to be dependent on GFAP, since SCs cultured with both the cell lines formed similar processes. This coculture model may be useful in elucidating the factor(s) responsible for the formation of processes by SCs and can be further help in our understanding of the mechanism of morphological transformation of SCs.  相似文献   
6.
The kinetics of bilirubin erythrocyte interaction have been followed by scanning electron microscopy. Bilirubin-induced erythrocyte cytotoxicity embodies the interaction of the bile pigment with the outer half of the erythrocyte plasma membrane bilayer couple. This interaction leads to crenation. This membrane event appears to be primary and precedes hemolysis. The membrane crenation is dependent on the concentration of the bile pigment and is reversed by bovine serum albumin again in a concentration-dependent manner. Phospholipids do not alter bilirubin erythrocyte ineraction. Erythrocytes from jaundiced neonates show crenated surface structure in scanning electron microscopy. The crenation depends upon severity of jaundice in neonates. This suggests similarity between in vivo and in vitro mechanisms of cytotoxicity mediated by the bile pigment. Further, phototherapy reverses the process of membrane crenation. The in vivo photocatabolities isolated from urine of jaundiced neonates are nontoxic to erythrocyte membrane.  相似文献   
7.
Serum cholesterol, triglycerides and total lipids were estimated in twelve students exposed to varying degree of examination stress. Serum cholesterol and triglycerides exhibited a rise proportional to degree of examination stress whereas total lipids exhibited an initial rise followed by a fall. Values of all these parameters attained control level when the stress was over. The rise in serum cholesterol and triglycerides seems to be due to stress induced changes in hormonal levels and peripheral lipolysis respectively.  相似文献   
8.
Tephrosia purpurea (family: Fabaceae), which is used in traditional remedies for the treatment of febrile attacks, enlargement and obstruction of liver, spleen, and kidney, was found to have significant antileishmanial activity, and has been extensively fractionated to locate the abode of activity. A fraction (F062) obtained from N‐butanol extract of T. purpurea showed consistent antileishmanial activity at 50 mg/ kg × 5 days by oral route against Leishmania donovani infection in hamsters. Activity was further confirmed in a secondary model, i.e., Indian langur monkeys (Presbytis entellus). Thus, the fraction F062 from this plant possesses potential to produce significant antileishmanial activity by oral route without producing any toxic side effects. Drug. Dev. Res. 60:285–293, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
9.
Solitary kidneys in renal donors and patients who have undergone unilateral nephrectomy for malignant disease have been reported to undergo hyperfiltration injury. This study was undertaken to evaluate the somatic growth and development of followed-up patient after Wilms' tumor to evaluate their renal function and identify any evidence of injury in the remaining kidney. The growth and development of all the children was found to be normal, as was DTPA clearance. Microalbuminuria in 24-h urinary collections was detected in 84% of the patients, indicating evidence of hyperfiltration injury. This study highlights the need for close monitoring of the renal function of long-term follow-up patients after Wilms' tumor in addition to the routine monitoring for tumor recurrence. Accepted: 26 May 1998  相似文献   
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