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991.
There is a large body of evidence for the role of thymosin peptides in immunogenesis and immunity. In this paper we report on the influence of prothymosin alpha 1 (ProT-alpha 1), a hormone-like peptide derived from the calf thymus, on humoral and cellular immune reactions in the rat. Young adults received intraperitoneal injections of ProT-alpha 1 in the periods before and after immunization with cellular and soluble antigens. ProT-alpha-treatment produced a dose-dependent increase of both humoral and cell-mediated immune responses. The thymus weight increased but not that of spleen. Treatment of nonimmunized rats with this polypeptide significantly elevated the number of CD4+ and decreased the number of CD8+ cells in the peripheral blood. The results suggest a potent immunostimulatory activity of ProT-alpha 1 and imply direct action of this polypeptide on T lymphocytes.  相似文献   
992.
Using a sandwich enzyme-linked immunoassay, plasma total cathepsin D concentration was assayed in 40 breast cancer patients and 84 patients with various liver diseases and compared to that of 52 normal subjects. There were no significant variations found in breast cancer patients related to tumor size, node invasiveness or metastases. In normal women, cathepsin D levels were slightly but not significantly increased in the luteal phase and in pregnancy. By contrast, plasma cathepsin D concentration was significantly increased in 70-75% of patients with liver disease (cirrhosis, hepatocarcinoma, hepatitis), but not in those with liver steatosis. Cathepsin D was independent of most of the plasma hepatic function tests and was correlated with alpha-fetoprotein in cirrhosis and with alpha-fucosidase in primary hepatocellular carcinoma. We conclude that plasma cathepsin D is not a useful marker in breast cancer. However, since the cellular level of this protease is associated with risk of metastasis in breast cancer, clinical follow-up will be required to test whether high cathepsin D plasma concentration has any prognostic value in liver cirrhosis and primary hepatocarcinoma.  相似文献   
993.
This paper outlines the development and construction of an instrument for use on an ambulatory subject which monitors selected physiological and environmental parameters that are a reflection of the degree of physiological strain associated with heat stress. The resulting instrument is rugged, reliable, and uses existing practical technology for in-the-field ambulatory monitoring, and provides minimal restriction to subject movement. The physiological parameters monitored (heart rate and skin temperature) were selected following examination of systemic, skin, and psychoneurotic heat disorders, with the environmental parameters (wind velocity, ambient temperature and relative humidity) based on existing heat stress indices' correlation with physiological parameters. A microprocessor is utilized for data acquisition, mathematical computation and long term storage, and software for downloading the data to a large mainframe computer is provided. Following calibration of the transduction circuits, the instrument was assembled and tested. Improvements are required to obtain the reliability originally envisaged. Additional field trials would see the collection of data to establish criteria to determine the values of the parameters monitored enabling prediction of the onset of heat stress in hot, humid environments.  相似文献   
994.
The authors reviewed the radiographic manifestations of 17 cases of parosteal osteosarcoma, with pathologic correlation in 15. There were two types of parosteal osteosarcoma radiologically. The majority of cases were type I with uniformly dense masses which had regular borders. They often adhered to the cortex and showed no evidence of soft-tissue invasion which correlated with low-grade pathologic malignancy and a relatively benign clinical course. Type II involved the bone, soft-tissue and the medullary cavity. These lesions were poorly differentiated and frequently accompanied by metastatic lesions.
  相似文献   
995.
A model of sleep phasic events such as vertex waves, K complexes, delta waves and sleep spindles is proposed. It consists of feedback loops that are driven by white noise (simulating tonic delta and sigma activity) and by isolated random impulses, simulating vertex waves or K complexes, depending on the background tonic activity. A model-based method for the detection of sleep phasic events was implemented in a personal computer. Its performance was investigated using simulated and real whole-night EEG signals. The method was able to detect K complexes and vertex waves in a reliable way in spite of their variable shapes and in the presence of a variety of background activities. The detector appears to have superior performance to those so far reported in the literature. The performance of the detector was also compared to that of an electroencephalographer using normal sleep EEG records of 8 h duration from 6 subjects. The performance was satisfactory both in terms of accuracy and reliability. The problem of detecting K complexes in stages 3 and 4 of sleep is discussed.  相似文献   
996.
997.
Data obtained on a sample of persons with mild to profound degrees of mental retardation (N = 8255) and ranging from birth to 98 years of age were factor analyzed to provide information on the structure of maladaptive behavior relative to age and degree of mental retardation. Using the Problem Behavior scales of the Inventory for Client and Agency Planning, two principal factors emerged for children with mild to profound degrees of retardation: Internalized Maladaptive and Externalized Maladaptive. For adolescents and young adults, a three-factor solution which varied by degree of retardation was most appropriate. For middle and older adults, three- and four-factor solutions were identified across all ages and degrees of retardation. Across all samples as many as six different types of dimensions were identified, indicating that the structure of maladaptive behavior may well be influenced by age and level of mental retardation.  相似文献   
998.
The interpretation of the total phenytoin (PT) concentration can be problematic if valproic acid (VPA) is given as a comedication, because VPA displaces PT from the protein binding sites and can increase the free fraction of PT. In order to estimate the free or unbound PT concentration (PTf) from the total PT concentration (PTt) and VPA concentration, a nomogram was constructed and evaluated. Data of 84 patients on combined therapy with PT and VPA were used in drawing up the regression equation (PTf = 0.0792.PTt + 0.000636.PTt.VPA) from which the nomogram was constructed. The predictions were checked using another 33 patients whose serum concentrations were determined in the morning and in addition several times during the day. The results show that using this method the PTf concentrations can be accurately estimated from the PTt and VPA concentrations.  相似文献   
999.
1000.
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