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141.
Human papillomavirus (HPV) DNA detection in self-collected urine 总被引:1,自引:0,他引:1
B.K. Prusty A. Kumar R. Arora S. Batra B.C. Das 《International journal of gynaecology and obstetrics》2005,90(3):223-227
OBJECTIVE: Non-invasive sampling of human genitals to identify high-risk individuals with subclinical oncogenic HPV infection remains a challenge. The study was designed to see if self-collected urine can be used as a simple, non-invasive sampling for screening HPV, particularly for screening/monitoring general population or young adolescents or infants, if they are to be immunized by HPV vaccines. METHOD: Self-collected urine samples from 100 sexually unexposed college going girls and cervical scrapes from 104 normal healthy sexually active married women were used in this study. Additionally, a group of 55 women were recruited for collecting first urine and later scraped cervical cells to validate urine sampling by directly comparing HPV positivity between the two types of biological specimens. A dry 'paper smear' method for specimen collection and a simple single tube protocol was employed for PCR detection of HPV infection. RESULTS: Out of 100 sexually inexperienced college going girls, only 6 (6%) were positive for HPV infection as revealed by L1 consensus primer and 4 (4%) of them were positive for HPV 16 but none was found positive for HPV 18 DNA. Out of 104 sexually active married women who were cytologically reported as negative by Pap test, 11 (10.5%) were found HPV positive and 7 (6.7%) of them had infection of high-risk HPV type 16. Both urine and later cervical scrapes from a group of 55 women collected as dry 'paper smear' showed perfect matching positivity for HPV between urine and cervical scrape. CONCLUSIONS: The use of urine coupled with its dry collection as 'paper smear' facilitating their easy transport, storage and direct PCR detection of HPV DNA opens up an alternative non-invasive approach for population screening of HPV infection, at least in such cases as children and infants in whom invasive samples are difficult to obtain. 相似文献
142.
143.
JR Bapuraj V Ojili SK Singh GRV Prasad N Khandelwal S Suri 《Journal of Medical Imaging and Radiation Oncology》2006,50(2):179-182
Leiomyoma of the vagina is a very rare tumour of the lower urogenital tract. These slow‐growing masses may be asymptomatic or present with pain, dyspareunia or urinary symptoms. Rarely, these tumours may present with life‐threatening haemorrhage. These hypervascular tumours are treated by surgical excision. Preoperative embolization therefore may aid in devascularization of these tumours before surgical excision. We present the MRI features of a case of vaginal leiomyoma, which was managed by preoperative embolization and was then excised in toto. To the best of our knowledge, this is the first report where preoperative embolization was performed before excision of a vaginal leiomyoma with minimal peroperative blood loss. 相似文献
144.
The study was undertaken to investigate the possible role of free radicals and antioxidants in childhood meningitis. Sixty children suffering from acute bacterial meningitis (ABM) or tuberculous meningitis (TBM) according to their clinical and laboratory findings were enrolled in the study. The production of superoxide anions (O2.-), hydrogen peroxide (H2O2) and malondialdehyde (MDA) and the activities of xanthine oxidase (XO), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were monitored in the study groups and findings compared with those in 20 age-matched controls. Children with ABM and TBM who died registered significant increases in the production of O2.- and MDA and in the activities of SOD and CPK compared with survivors. The rate of production of oxidants and MDA and the activities of XO, SOD and CPK were of a much higher magnitude in deceased ABM and in ABM survivors than in fatal TBM and survivors, respectively. The abnormalities in most of the biochemical parameters investigated were more marked in the children with ABM than in TBM and controls (p < 0.001). Increased MDA production and creatine phosphokinase (CPK) activity of different magnitudes in the two study groups suggest varying degrees of tissue damage. The alterations observed in 20 children who died (14 from ABM, 6 from TBM) revealed elevated levels of oxidants, antioxidants and toxicity markers, particularly in ABM patients, which suggests the possibility that natural or synthetic antioxidants might prevent disease progression and tissue damage in childhood meningitis. 相似文献
145.
Free oxygen radicals in acute renal failure 总被引:11,自引:0,他引:11
OBJECTIVE: To assess the levels of free oxygen radicals in acute renal failure and their predictive value in clinical outcome. DESIGN: Prospective. SETTING: Intensive care unit. METHODS: Study was conducted in 50 children (25 with acute renal failure and 25 age and sex matched controls). Blood urea, serum creatinine, serum protein, uric acid and free oxygen radical markers were estimated in both groups. Superoxide dismutase (SOD), glutathione peroxidase(GPx) and lipid peroxide (LPO) were estimated in blood by standard techniques. RESULTS: Hemolytic uremic syndrome (HUS) was a major cause of acute renal failure (52%), rest were due to acute glomerulonephritis (AGN), septicemia and renal venous thrombosis. In the renal failure group 56% of the patients were dialyzed (peritoneal) and the mortality was 28% (7/25). The levels of SOD, GPx and LPO were significantly raised in renal failure group. Higher values of LPO, SOD and GPx were documented in subjects who expired. The most important independent variable for predicting clinical outcome was LPO with a sensitivity of 89.4%, specificity of 93%, positive predictive value of 95%. CONCLUSION: Levels of free oxygen radicals (SOD, LPO and GPx) are raised in acute renal failure and these enzymes can be used as marker of renal injury. LPO levels are highly sensitivity and specific for predicting the clinical outcome 相似文献
146.
Emerging evidence suggests that the capacity of a tumor to grow and propagate is dependent on a small subset of cells within a tumor, termed cancer stem cells. In fact, cancer cells, like stem cells, can proliferate indefinitely through a dysregulated cellular self-renewal capacity. Cancer stem cells may originate due to the distribution into self-renewal and differentiation pathways occurring in multi-potential stem cells, tissue-specific stem cells, progenitor cells and cancer cells. Recent studies have shown that ovarian cancer also contains stem cells or tumor-initiating cells. Moreover, ovarian serous adenocarcinomas were disaggregated and subjected to growth conditions to select for self-renewing, non-adherent spheroids previously shown to be derived from tissue stem cells. A recent study showed that epithelial ovarian cancer was derived from a sub population of CD44+, CD117+ and CD133+ cells. The existence of cancer stem cells would explain why only a small minority of cancer cells is capable of extensive proliferation of the tumor. In this review, we have discussed the studies on ovarian cancer stem cells along with the molecular pathways that could be involved in these cancer stem cells. 相似文献
147.
RJ Gilbertson E Harris SK Pandey P Kelly W Myers 《Archives of disease in childhood》1996,75(3):194-198
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning. 相似文献
148.
149.
Evaluation of the pharmacokinetics and electrocardiographic pharmacodynamics of loratadine with concomitant administration of ketoconazole or cimetidine 下载免费PDF全文
Kosoglou T Salfi M Lim JM Batra VK Cayen MN Affrime MB 《British journal of clinical pharmacology》2000,50(6):581-589
AIMS: To evaluate whether ketoconazole or cimetidine alter the pharmacokinetics of loratadine, or its major metabolite, desloratadine (DCL), or alter the effects of loratadine or DCL on electrocardiographic repolarization in healthy adult volunteers. METHODS: Two randomized, evaluator-blind, multiple-dose, three-way crossover drug interaction studies were performed. In each study, subjects received three 10 day treatments in random sequence, separated by a 14 day washout period. The treatments were loratadine alone, cimetidine or ketoconazole alone, or loratadine plus cimetidine or ketoconazole. The primary study endpoint was the difference in mean QTc intervals from baseline to day 10. In addition, plasma concentrations of loratadine, DCL, and ketoconazole or cimetidine were obtained on day 10. RESULTS: Concomitant administration of loratadine and ketoconazole significantly increased the loratadine plasma concentrations (307%; 90% CI 205-428%) and DCL concentrations (73%; 62-85%) compared with administration of loratadine alone. Concomitant administration of loratadine and cimetidine significantly increased the loratadine plasma concentrations (103% increase; 70-142%) but not DCL concentrations (6% increase; 1-11%) compared with administration of loratadine alone. Cimetidine or ketoconazole plasma concentrations were unaffected by coadministration with loratadine. Despite increased concentrations of loratadine and DCL, there were no statistically significant differences for the primary electrocardiographic repolarization parameter (QTc) among any of the treatment groups. No other clinically relevant changes in the safety profile of loratadine were observed as assessed by electrocardiographic parameters (mean (90% CI) QTc changes: loratadine vs loratadine + ketoconazole = 3.6 ms (-2.2, 9.4); loratadine vs loratadine + cimetidine = 3.2 ms (-1.6, 7.9)), clinical laboratory tests, vital signs, and adverse events. CONCLUSIONS: Loratadine 10 mg daily was devoid of any effects on electrocardiographic parameters when coadministered for 10 days with therapeutic doses of ketoconazole or cimetidine in healthy volunteers. It is concluded that, although there was a significant pharmacokinetic drug interaction between ketoconazole or cimetidine and loratadine, this effect was not accompanied by a change in the QTc interval in healthy adult volunteers. 相似文献
150.
Discharge patterns of neurons in the ventral nucleus of the lateral lemniscus of the unanesthetized rabbit. 总被引:1,自引:0,他引:1
The ventral nucleus of the lateral lemniscus (VNLL) is a major auditory nucleus that sends a large projection to the inferior colliculus. Despite its prominence, the responses of neurons in the VNLL have not been extensively studied. Previous studies in nonecholocating species have used anesthesia, which is known to affect discharge patterns. In addition, there is disagreement about the proportion of neurons that are sensitive to binaural stimulation. This report examines the responses of neurons in the VNLL of the unanesthetized rabbit to monaural and binaural stimuli. Most neurons responded to contralateral tone bursts at their best frequency and had either sustained or phasic discharge patterns. A few neurons were only inhibited. Most sustained neurons were classified as short-latency sustained (SL-sustained), but a few were of long latency. Some SL-sustained neurons exhibited multiple peaks in their discharge pattern, i.e., they had a "chopper" discharge pattern, whereas other SL-sustained neurons did not exhibit this pattern. In ordinary chopper neurons, the multiple peaks corresponded to the evenly spaced action potentials of a regular discharge. In unusual chopper neurons, the action potential associated with a particular peak could fail to occur during any one presentation of the stimulus. Unusual chopper neurons had a relatively irregular discharge. Phasic neurons were of two types: onset and transient. Onset neurons typically responded with a single action potential at the onset of the tone, whereas transient neurons produced a burst of action potentials. Transient neurons were relatively rare. About half the neurons also were influenced by ipsilateral stimulation. Most binaurally influenced neurons were either sensitive to interaural temporal disparities (ITDs) or excited by contralateral stimulation and inhibited by ipsilateral stimulation. Neurons sensitive to ITDs were mostly of the onset type and were embedded in the fiber tract medial to the main part of the nucleus. Neurons inhibited by ipsilateral stimulation could be of the sustained or onset type. The sustained neurons were located on the periphery of the main nucleus as well as in the fiber tract. Most of the monaural neurons were in the main, high-density part of VNLL. The present results demonstrate that the VNLL contains neurons with a heterogeneous set of responses, and that many of the neurons are binaural. 相似文献