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31.
The anti-inflammatory effect of the leaves of Bryonia laciniosa was evaluated using carrageenan, dextran, histamine, serotonin induced rat paw oedema and cotton pellet induced granuloma (chronic) models in rats. In mice, carrageenan peritonitis test was performed for the extract by oral administration. The chloroform extract of Bryonia laciniosa (CEBL) exhibited significant anti-inflammatory effect at the dose 50, 100 and 200 mg/kg. Maximum inhibition (52.4%) was noted at the dose of 200 mg/kg after 3 h of drug treatment in carrageenan induced paw oedema, whereas the indomethacin (standard drug) produced 62.1% of inhibition. The extract exhibited significant anti-inflammatory activity in dextran induced paw oedema in a dose dependent manner. The extract also exhibited significant inhibition on the hind paw oedema in rats caused by histamine and serotonin respectively. In the chronic model (cotton pellet induced granuloma) the CEBL (200 mg/kg) and standard drug showed decreased formation of granuloma tissue by 50.1 and 57.3% (p<0.001) respectively. The extract also inhibited peritoneal leukocyte migration in mice. Thus, the present study revealed that the chloroform extract of Bryonia laciniosa exhibited significant anti-inflammatory activity in the tested models.  相似文献   
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In the field of diagnostic medicine, comparative clinical trials are necessary for assessing the utility of one diagnostic test over another. The area under the receiver operating characteristic (ROC) curve, commonly referred to as AUC, is a general measure of a test's inherent ability to distinguish between patients with and without a condition. Standardized AUC difference is the most frequently used statistic for comparing two diagnostic tests. In therapeutic comparative clinical trials with sequential patient entry, fixed sample design (FSD) is unjustified on ethical and economical grounds and group sequential design (GSD) is frequently used. In this paper, we argue that the same reasoning exists for the comparative clinical trials in diagnostic medicine and hence GSD should be utilized in this field for designing trials. Since computation of the stopping boundaries of GSD and data analysis after a group sequential test rely heavily on Brownian motion approximation, we derive the asymptotic distribution of the standardized AUC difference statistic and point out its resemblance to the Brownian motion. Boundary determination and sample size calculation are then illustrated through an example from a cancer clinical trial.  相似文献   
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This paper presents an application of a hybrid approach (the genetic algorithms and the k-nearest neighbour) proposed by Ishbuchi to Wisconsin breast cancer data. For the diagnosis of breast cancer, the determination of the presence of benign/malignant breast tumors represents a very complex problem (even for an experienced cytologist). Therefore the automatic classification of benign and malignant symptoms is highly desirable as a valuable aid to assist oncologists in the decision making of the diagnosis of breast cancer. In this paper, the genetic algorithm based k-nearest neighbour method for classification of benign and malignant breast tumors is presented. The genetic-algorithm (GA) is used for finding a compact reference set by selecting a small number of reference patterns from a large number of training patterns in nearest neighbor classification. The GA simultaneously performs feature selection and pattern selection and prunes unnecessary features. The goal is to maximize the classification performance of the reference set and minimize the number of selected patterns and features. Results are also compared with a fuzzy-genetic approach where each reference patten represents a fuzzy if-then rule with a circular-cone-type membership function.  相似文献   
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Advanced head and neck cancer is a major therapeutic problem in India. Ifosfamide has shown significant activity as a single agent in head and neck squamous carcinoma. In this study, we present our experience with two cycles of ifosfamide and cisplatin in the neoadjuvant setting given to a total of 519 patients. The complete response rate was 20% and the overall response rate was 80%. The treatment was well tolerated, there was no need for dose reduction, and there were no life-threatening side effects. We feel that this high response rate is sufficient to warrant more studies using ifosfamide-based combinations in a neoadjuvant setting for squamous carcinoma of the head and neck.  相似文献   
35.
PURPOSE: The variation in reported survival of patients with metastatic transitional-cell carcinoma (TCC) treated with systemic chemotherapy may be a consequence of pretreatment patient characteristics. We hypothesized that a prognostic factor-based model of survival among patients treated with methotrexate, vinblastine, doxorubicin, and cisplatin chemotherapy could account for such differences and help guide clinical trial design and interpretation. PATIENTS AND METHODS: A database of 203 patients with unresectable or metastatic TCC was retrospectively subjected to a multivariate regression analysis to determine which patient characteristics had independent prognostic significance for survival. Patients were assigned to three risk categories depending on the number of unfavorable characteristics. Patient selection in phase II studies was addressed by developing a table of expected median survival for patient cohorts that had varying proportions of patients from the three risk categories. RESULTS: Two factors had independent prognosis: Karnofsky performance status (KPS) less than 80% and visceral (lung, liver, or bone) metastasis. Median survival times for patients who had zero, one, or two risk factors were 33, 13.4, and 9.3 months, respectively (P =.0001). The median survival time of patient cohorts could vary from 9 to 26 months simply by altering the proportion of patients from different risk categories. CONCLUSION: The presence of baseline KPS less than 80% or visceral metastasis has an impact on survival. Reporting the proportion of patients with zero, one, and two risk factors will facilitate understanding of the relevance of the median survival in phase II trials. Phase III trials should stratify patients according to the number of risk factors to avoid imbalance in treatment arms.  相似文献   
36.
Loss of chromosome 6q21-qter is the second most frequent loss of chromosomal material in sporadic breast neoplasms suggesting the presence of at least one tumor suppressor gene on 6q. We recently isolated a cDNA encoding a new zinc finger protein which we named ZAC according to its functional properties, namely induction of apoptosis and control of cell cycle progression. ZAC is expressed in normal mammary gland and maps to 6q24-q25, a recognized breast cancer hot spot on 6q. In the present report, we investigated the possible inactivation of ZAC in breast cancer cell lines and primary tumors. We detected no mutation in ZAC coding region in a panel of 45 breast tumors with allelic imbalance of 6q24-q25. However, a survey of eight breast cancer cell lines showed a deeply reduced (three cell lines) or complete loss of (five cell lines) ZAC expression. Treatment of three of these cell lines with the methylation-interfering agent 5-azacytidine induced ZAC re-expression. In addition, Northern blot and RNase protection assay analysis of ZAC expression in 23 unselected primary breast tumors showed a reduced expression in several samples. Together with its functional properties and chromosomal localization, these findings substantiate ZAC as a good candidate for the tumor suppressor gene on 6q24-q25.  相似文献   
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OBJECTIVE: Deficits in executive functions may play an important role in late-life suicide; however the association is understudied. This study examined cognitive function in general and executive functioning specifically in depressed elderly with and without suicidal ideation and attempts. DESIGN: Case-control study. Setting: University-affiliated psychiatric hospital. PARTICIPANTS: We compared 32 suicidal depressed participants aged 60 and older with 32 non-suicidal depressed participants equated for age, education, and gender. MEASUREMENTS: We assessed global cognitive function and executive function with the Dementia Rating Scale (DRS) and the Executive Interview (EXIT25), respectively. RESULTS: Suicidal and non-suicidal depressed groups were comparable in terms of severity of depression and burden of physical illness. Suicidal participants performed worse on the EXIT25, and on the DRS total scale, as well as on Memory and Attention subscales. The differences were not explained by the presence of dementia, substance use, medication exposure, or brain injury from suicide attempts. CONCLUSIONS: Poor performance on tests of executive function, attention, and memory is associated with suicidal behavior in late-life depression.  相似文献   
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