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941.
942.
G.L. Wise 《Journal of The Franklin Institute》1977,303(2):201-207
Mean square continuity of a random process is of considerable theoretical and practical importance. Mean square continuous random processes passed through zero memory non-linearities are considered. Several conditions are given relating to mean square continuity of the output. Bounded zero memory non-linearities are considered with arbitrary random processes as inputs, and conditions on both the zero memory non-linearity and on the random process are examined. Also, general zero memory non-linearities are considered with Gaussian random processes as inputs. 相似文献
943.
Warranting scientific belief 总被引:1,自引:0,他引:1
944.
Design of detectors for strong mixing signals in strong mixing noise is considered, where a large degree of dependency may occur between the signal and noise. Under the criterion of asymptotic relative efficiency, it is shown that this design reduces to determining the solution of an integral equation, where only knowledge of the second order statistics of the randon processes involved is required. In particular, if the signal is independent of the noise and has nonzero mean, the optimal detector is the same as in the known constant signal case. It is also shown that it is possible to delete several regularity conditions which may be difficult to check in practice in the slightly more restrictive case where the maximal correlation coefficients of the signal and noise tend to zero. 相似文献
945.
Varinder Saini Narinder Saini Jasbinder Kaur G. P. Singh 《Indian journal of clinical biochemistry : IJCB》1993,8(1):36-38
348 patients of chronic obstructive pulmonary diseases (COPD) were studied for their acid base profile using ABL-3 blood gas
analyser (Radiometer, copenhagan). 185 patients (53.1%) had simple disorders (respiratory acidosis—53%, respiratory alkalosis—25.4%,
metabolic acidosis—11.3%, metabolic alkalosis—10.2%). Mixed disorders were present in 131 patients (34.9%) (respiratory acidosis
and metabolic acidosis—75.2%, respiratory acidosis and metabolic acidosis—14%, metabolic acidosis and metabolic alkalosis—5.7%,
metabolic alkalosis and respiratory alkalosis—4.9%). Hypoxemia without other acid base abnormalities was observed in early
patients of GOPD (42 patients—12%). Chronic respiratory acidosis was the most common finding in advanced cases of COPD (98%).
An almost equal number of such patients had a mixed disorder of respiratory acidosis with metabolic alkalosis (91%). Salt
restriction, prolonged use of steriods and hypokalemia were often related to metabolic alkalosis in such patients. 相似文献
946.
利用双标图分析基因型和环境交互作用 总被引:28,自引:0,他引:28
在作物的品种区域化试验中,品种的基因型和环境(G×E)交互作用越来越受到重视.一种新的非常有效的分析G×E交互作用模型是加性主效应和乘积交互作用模型(简称AMMI模型),而双标图(biplot)是解释AMMI分析结果的一种直观有效的图形工具.本文对AMMI模型及双标图作一扼要介绍,并选用1995年南方水稻区试单季晚粳组数据作为实例,给出了两种新的双标图,以帮助我们更深入地了解G×E交互作用. 相似文献
947.
Gamma Glutamyl Transferase (γ-GT) is a microsomal enzyme. Its activity in serum is assayed in alcoholics with liver abscess
and alcoholics without liver abscess after screening by ultrasonography. The enzyme activity in serum is increased by 334%
in the patients with liver abscess compared to normal control subjects (p<0.0001), and 172% when compared to patients with
chronic alcoholism without liver abscess (p<0.0001). The enzyme activity was increased by 59.3% in the serum of patients without
liver abscess compared to the normal control subjects (p<0.001). Measurement of γ-GT in serum appears to be a sensitive index
in the diagnosis of alcoholics with liver abscess. 相似文献
948.
本文对秦始皇兵马俑博物馆室内采集的长短期降尘、大气悬浮颗粒物和彩绘漆层进行了SEM-EDX研究,在大气悬浮颗粒、短期和长期降尘中,含硫颗粒的粒径分别为0.9~22.8μm、1.0~29.0μm和1.2~37.7μm,多为石膏与粘土或石英以内部混合的状态存在。降尘中的附着型絮状硫酸钙多于大气悬浮颗粒物中,显示降尘和大气中的二氧化硫发生了累进的化学反应。彩绘漆层表面的坑和裂隙附近观察到原位生长的硫酸钙晶体,显示漆层材料或降尘颗粒物与大气二氧化硫之间的酸化学反应,可能是彩绘漆层表面受侵蚀形成微小坑和裂隙的原因之一。 相似文献
949.
T. Malati G. Rajani Kumari I. Dinakar 《Indian journal of clinical biochemistry : IJCB》1995,10(2):72-76
Humoral immune response against PPD derived A60 antigen was evaluated by quantification of serum A60 antibodies in thrity healthy adults not exposed to tuberculosis (Group 1), in twenty seven healthy adults exposed to tuberculosis patients i.e. staff working in wards of tuberculosis hospital for one to thirty years (group 2), in twenty five pulmonary tuberculosis patients admitted to the Institute for Chest Diseases, Hyderabad (Group 3) and in sixty neurotuberculosis patients admitted to Neurosurgery department of our institute (Group 4). Highly significant elevation of A60 antibodies was observed in pulmonary tuberculosis patients (p<0.01) compared to healthy adult groups. A significant elevation in serum was also observed in case of neurotuberculosis group compared to both healthy groups (p<0.01). A test on A60 antibodies in serum gavv a sensitivity of 100%, specificity of 96.6%, positive predictive value of 81% and negative predictive value of 100% for pulmonary tuberculosis, whereas a sensitivity of 58%, positive predictive value of 79% and negative predictive value of 75% were noted for neurotuberculosis patients. Results of A60 antibodies in ten cerebrospinal fluids (CSF) obtained from non tuberculosis patients and thirty two CSF from patients of neurotuberculosis did not show significant elevation of antibodies. However the ninetyfive percentile value of CSF A60 antibodies was higher in neurotuberculosis (7.4 U/ml) group compared to nontuberculous group (3.8 U/ml) and the test showed a good positive predictive value (83%), very low negative predictive value (25%) and low sensitivity (63%). Serum A60 antibody assay appears to be a good serological marker available today for pulmonary tuberculosis and a supportive marker for neurotuberculosis. 相似文献
950.
T. Malati G. Rajani Kumari B. Yadagiri 《Indian journal of clinical biochemistry : IJCB》2001,16(2):224-233
Ovarian cancer is the fifth leading cause of death in women. The incidence of this malignancy increases in women over the
age of 40. The overall five years survival is less than 30%, as most women present with advanced stage disease. Until recently,
detection of early stage ovarian cancer has been difficult since it is usually nonpalpable and asymptomatic. The definitive
diagnosis of an ovarian mass is a common problem in gynecologic patients with adnexal mass. The routine standard evaluation
for adnexal masses includes patient's history, physical examination, ultrasound and histopathological examination. These parameters
individually or in combination have little predictive value. The accuracy of diagnostic tools are of immense value and great
concern to practicsing Gynecologists and Oncologists. The clinical application of serum concentration of CA 125, AFP and hCG
is of great help not only as diagnostic aid but also in monitoring efficacy of any treatment modality like chemotherapy, radiotherapy
or surgical resection. Additionally, evaluation of tumor marker concentration helps in predicting early biochemical recurrence
and in prognostication in different types of ovarian malignancies. The ability to differentiate a malignant mass from a benign
pelvic mass pretherapeutically could be enhanced optimally by additional use of tumor markers such as cancer antigen CA-125,
alphafetoprotein and human chorionic gonadotrophin in pre-and postmenopausal women. 相似文献