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1.
The goals of this report are: 1) to review the number needed to treat (NNT) concept, which, although well established in many sectors of medicine, is still relatively new to the radiotherapy community; 2) to discuss several clinical radiotherapy examples illustrating the inherent advantages of the NNT approach; and 3) to discuss potential future roles of the NNT concept within radiotherapy. 相似文献
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S Vijayakumar K Shepard F Thomas J Weick T Rice A Mehta 《Journal of the National Medical Association》1987,79(5):496-504
The role of radiotherapy in small cell carcinoma of the lung is unsettled; however, the radiosensitivity of this neoplasm is unquestioned. The ability of radiotherapy to cure or improve patients with this disease is still undergoing study. A review of this challenging subject is presented. 相似文献
4.
STUDY OBJECTIVES: Considerable evidence suggests that rapid eye movement (REM) sleep is induced by glutamatergic activation of cholinergic cells within the pedunculopontine tegmentum (PPT). The aim of this study is to test a popular hypothesis that serotonin, norepinephrine, and adenosine act on PPT cells to regulate REM sleep. This study also tests an alternate hypothesis that serotonin may inhibit REM sleep signs by direct action on the individual REM sleep sign generators. DESIGN: Serotonin, norepinephrine, and adenosine were locally microinjected into the PPT and serotonin was microinjected into the pontine-wave (P-wave) generator (dorsal part of the locus subcoeruleus nucleus) while quantifying the effects on REM sleep and P-wave activity in freely moving rats. SETTING: N/A. PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Local microinjections of serotonin, norepinephrine, and adenosine into the PPT did not change REM sleep. Microinjection of serotonin into the P-wave generator suppressed P-wave activity but not REM sleep. CONCLUSIONS: The present findings provide direct evidence that serotonin, norepinephrine, and adenosine-induced REM sleep suppression in the behaving rat are not mediated by the PPT. The results also provide direct evidence, for the first time, that serotonin suppresses P-wave activity by acting directly on the P-wave generator. These results suggest that the serotonin-induced inhibition of REM sleep in the freely moving rat is probably not mediated through the mesopontine cholinergic cell compartment but, rather, through individual REM sleep sign generators. 相似文献
5.
Kannangai R Ramalingam S Vijayakumar TS Vincent AA Abraham OC Subramanian S Rupali P Mathai D Jesudason MV Sridharan G 《Indian journal of medical microbiology》2003,21(4):274-276
Currently, antiretroviral therapy has become more affordable even in developing countries and it is being used in India. Fifteen HIV-1 infected individuals, who were on highly active antiretroviral therapy (HAART), were followed up for an average period of one year. The plasma viral load and CD4+ T cell estimation done at mean intervals of 5 months and 11 months after initiation of therapy showed a good response to therapy in 14 (93%) individuals. 相似文献
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The enzyme, acetylcholinesterase, activity of the brain was measured in control and clomipramine-induced behaviorally depressed rats. Compared with control rats, the soluble form of acetylcholinesterase activity of the depressed rats was 31.8% higher in the hippocampus and 26.0% lower in the frontal cortex. However, the activity of soluble form of this enzyme was not significantly different in the hypothalamus, septum, and brainstem. These results suggest for the first time that the altered cholinergic activity in the specific areas of the brain may be involved in the behavioral depression observed in the rat model of human endogenous depression. 相似文献
7.
T. Vijayakumar Ravindran Ankathil P. Remani V. M. Haseena Beevi K. K. Vijayan C. K. Jayaram Panicker 《Journal of clinical immunology》1987,7(4):300-303
The total hemolytic complement activity of CH50 and its fractions C3 and C4 was determined in the sera of 196 patients with carcinoma of the oral cavity, 172 patients with carcinoma of the uterine cervix, and 166 patients with breast cancer. The values were compared with those of 18 patients with mammary dysplasia, 32 patients with mild to moderate dysplasia of the cervix, and 100 healthy, normal age- and sex-matched controls. No alterations in CH50, C3, and C4 were observed in the sera of patients with benign lesions, whereas a significant rise in the three factors was observed in all the cancer patients studied. The complement activity increased significantly with the progression of the disease up to stage III and remained persistently elevated thereafter. Patients who had a clinical cure had normal levels of CH50, C3, and C4, whereas the values remained elevated in patients who were still undergoing treatment for residual lesions. 相似文献
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S. Vijayakumar S. F. Quadri L. Dong L. Ignacio I. N. Kathuria H. Sutton H. Halpern 《Journal of the National Medical Association》1995,87(11):813-819
This cross-sectional study was undertaken to determine whether serum hormones (free testosterone, androstenedione, luteinizing hormone, or prolactin) have any influence on serum prostate specific antigen (PSA) levels in patients with stage A-C prostate cancer. Blood samples were collected prior to any treatment in 36 patients; in 19 (group 1), three blood samples were collected 10 minutes apart between 9:00 AM and 9:30 AM for each patient and pooled together to avoid diurnal and episodic variation in serum testosterone values. In the remaining patients, only one sample could be collected (group 2). Free testosterone, androstenedione, luteinizing hormone, prolactin, and PSA levels were determined with appropriate radioimmunoassay techniques. Statistical analyses were performed separately for groups 1 and 2, and then with pooled data. None of the hormones in any of the analyses showed any association to serum PSA values except for prolactin for the pooled data and for group 2. This statistical significance for prolactin disappeared on multivariate analysis. There were 21 African-American men and 15 whites in the study; no racial differences in hormonal levels were found except for lower luteinizing hormone levels in African Americans in group 2 and pooled data. No differences were found between group 1 and group 2 in the mean serum prolactin and luteinizing hormone values. Serum free testosterone, androstenedione, and luteinizing hormone appeared to have no influence on serum PSA values in nonmetastatic cancer patients. Serum prolactin values were inversely associated with PSA values in univariate analysis for the pooled data; this disappeared in multivariate analysis. Unlike other studies that found higher serum testosterone levels in African-American college students than whites, no such differences were seen in this age group. Luteinizing hormone was lower in African-American men than in whites in the pooled study population. Further studies are needed to clarify our findings. 相似文献
10.
Ankathil R Vijayakumar T Nesy E Chandini R Beena V Abraham E Nair M 《Oncology reports》1997,4(1):187-190
The AgNOR technique, was applied to oral tissue sections of 185 oral cancer, 42 oral leukoplakia, 37 oral submucous fibrosis and 10 normal subjects to investigate whether any correlation held good in these different tissues. Compared to the AgNOR counts in normal oral epithelium, there was a gradation in increase in the mean AgNOR counts from oral leukoplakia to oral submucous fibrosis to oral carcinoma (P<0.01). This suggests that AgNOR count parallels with the degree of neoplastic transformation of oral epithelium. Three oral submucous fibrosis patients who showed very high AgNOR counts as that of oral cancer patients, later developed oral carcinoma. Among the oral cancer tissues, the moderately and poorly differentiated subtypes showed higher AgNOR counts and scattered distribution pattern than the well differentiated subtype which showed a clustered distribution pattern. These results suggest that AgNOR technique can be utilised as a diagnostic and prognostic indicator in premalignant and malignant oral tissues. 相似文献