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631.
632.
Cell-mediated immunity (CMI) and circulating immune complexes (CIC) were estimated in 55 cancer patients and 25 control volunteers to evaluate their prognostic significance. Cancer patients comprised head and neck cancer (11), breast cancer (13), gastrointestinal cancer (10), genitourinary cancer (11), and lymphomas and sarcomas (10). CMI was tested in vitro by early rosette-forming cells (ARFC) and total rosette-forming cell (TRFC) counts. ARFC count in control group was 758.1 +/- 78.09 cells/cumm. In advancing clinical stages of cancer (I-IV), ARFC counts were decreased (i.e., 601.12 +/- 74.96 [p < 0.01]; 494.8 +/- 71.83 [p < 0.001]; 432.44 +/- 36.05 [p < 0.001], and 438.55 +/- 69.99 [p < 0.001] cells/cumm, respectively). TRFC count in control group was 1029 +/- 88.39 cells/cumm. In cancer stages I through IV, these counts decreased significantly (i.e., 699.63 +/- 66.24; 597.55 +/- 82.9; 505.11 +/- 52.56; and 501.55 +/- 69.99 cells/cumm, respectively [p < 0.001]. Dinitrochlorobenzene cutaneous reactivity in vivo was 100% positive in control group, 62.5% positive in cancer stage I, 5% positive in stage II, and negative in stages III and IV. CIC of intermediate size were estimated by polyethylene glycol precipitation (PEG pptn) technique, which detects CIC in the ratio of 2:1 (Ag2Ab). Mean PEG index in control group was 39.5 +/- 4.65; sequential increase in CIC was observed in advancing clinical stages of cancer (I-IV)(i.e., 49 +/- 7.03 [p < 0.01]; 75.38 +/- 44.01 [p < 0.001]; 93.38 +/- 44.57 [p < 0.001]; and 216.00 +/- 147.05 [p < 0.001], respectively). Latex agglutination inhibition (LAI) titer was done to detect CIC as small as 8s, which constitute the opposite polar end of CIC spectrum. LAI titers in control group were nil. However, LAI titers in cancer stages I through IV were 1 +/- 2.64; 8.6 +/- 5.6 (p < 0.001); 12.00 +/- 8.11 (p < 0.001); and 25.77 +/- 9.06 (p < 0.001), respectively. Decrease in CMI and subsequent increase in CIC indicate unfavorable prognosis in cancer patients, and also precede clinical manifestation of increased tumor mass in vivo. 相似文献
633.
The US Air Force continues to assess the mortality of veterans of Operation Ranch Hand, the unit responsible for aerially spraying herbicides in Vietnam. The authors of this study found that the cumulative all-cause mortality experience of these veterans was not different from that expected (standardized mortality ratio (SMR) = 1.0). Overall, cause-specific mortality did not differ from that expected regarding deaths from accidents, cancer, or circulatory system diseases, but the authors found that there was an increased number of deaths due to digestive diseases (SMR = 1.7, 95% confidence interval (CI) 0.9-3.2). When analyzing by military occupation, they found an increase in the number of deaths caused by circulatory system diseases (SMR = 1.5, 95% CI 1.0-2.2) among enlisted ground personnel, the subgroup with the highest dioxin levels. Most of the increase in the number of deaths from digestive diseases was caused by chronic liver disease and cirrhosis, and more than half of the increase in the number of deaths from circulatory system diseases was a result of atherosclerotic heart disease. In the subgroup of Ranch Hand veterans who had survived more than 20 years since their military service in Southeast Asia, the authors found no significant increase in the risk of death due to cancer at all sites (SMR = 1.1) and a nonsignificant increase in the number of deaths due to cancers of the bronchus and lung (SMR = 1.3). 相似文献
634.
The influence of u.v. exposure on developed positive resist pattern followed by hard baking and etching at low temperature has been utilized in the present work to produce grid structures without using metal pattern mask during substrate thinning of transit time devices. The present process eliminates one step of metallization which is required in the conventional method, and this reduces the overall cost of fabrication. The process reported in this paper can be used in selective etching of silicon in other areas of device fabrication as well. 相似文献
635.
A construct of IL-2 and pseudomonas exotoxin (PE40) has been genetically engineered. An aliquot of 100 microliter of the chimeric protein, radiolabelled with I125, was administered to healthy rats by various routes. At different intervals, ocular and non ocular tissues were removed and the levels of the radiolabelled chimeric protein IL-2-PE40 measured. Systemic administration of IL2-PE40 either intravenously (IV) or intraperitoneally (IP) leads to high levels of the drug in the blood, liver and spleen. Little or no radioactivity is observed within the ocular tissues using this route. On the other hand, local administration of the drug either as subtenon injection or as eye drops resulted in a very high concentration of the drug within the conjunctiva, cornea and sclera, with little radioactivity detected systemically. Subtenon injection induced a significant drug level within the optic nerve. With the drops, the chimeric protein was also detected, in low levels, intraocularly. 相似文献
636.
We present our study of polyacetylene photovoltaic junctions. Results indicate that barrier and depletion layer formation proceeds as if trans-(CH)x were atraditional p-type semiconductor with a small surface state density. A (CH)x: Al Schottky cell with junction internal conversion efficiency of 0.30% at low light level is reported. The effect of oxygen on the photosensitivity of (CH)x based devices is also discussed. 相似文献
637.
M. N. K. Chowdhury M. F. Mina A. K. M. M. Alam F. Akhtar M. M. Rahman 《Polymer-Plastics Technology and Engineering》2013,52(9):1087-1091
Aqueous solutions of acrylamide monomer were irradiated by γ-rays using a Co-60 source to synthesize polyacrylamide of different molecular weight (Mw). Solubility tests together with ultraviolet and infrared spectroscopic studies were performed for examining the irradiated samples to ensure that the prepared products were gradually converted from monomer to polymer (polyacrylamide), depending on the radiation dose. Various physico-chemical properties like polymer conversion, gel content, viscosity, and molecular weight of the products were determined. The conversion of polymer from monomer is initiated at a dose of 0.06 kGy and completed at about 0.14 kGy. The gel point, which indicates a dose for the onset of a network polymer structure, is identified to be 0.15 kGy providing valuable information about γ-ray synthesis of polyacrylamides. Viscosity and molecular weight are found to increase with radiation dose. Since polyacrylamides exhibit polyelectrolytic behavior in aqueous solutions, studies on conductivity changes of polyelectrolytes with respect to Mw, which is the main issue of this investigation, also were performed. The equivalent conductance of polyelectrolyte solutions was found to decrease with the molecular weight of the synthesized polymer. This change of conducting property of the prepared samples is explained based on the theory of polyelectrolyte solutions. 相似文献
638.
Jianjun Tian Xuanhui Qu Shengen Zhang Dawei Cui Farid Akhtar 《Materials Letters》2007,61(30):5271-5274
Radially oriented Sm(Co,Fe,Cu,Zr)z ring magnets are prepared by powder metallurgy with appropriate magnetic field molding, sintering process and aging treatment. The results indicate that radially oriented Sm(Co,Fe,Cu,Zr)z ring magnets have obvious anisotropy of thermal expansion and sintering shrinkage, which easily lead to the splits and deformation of the ring magnets. So, slow heating, vacuum pre-sintering in sintering process and various quenching processes at different steps during quenching are adopted. The magnets have excellent magnetic properties: Br = 10.8 kGs, Hcj = 27.6 kOe, BHmax = 28.1 MGOe. Besides, there is a uniform magnetization field on the surface of the ring magnets. The average surface magnetization field () is 1.502 kGs. The deviation from average (α) is only 4.2%. The microstructure of the magnets consists of a mixture of homogeneous cellular and lamella structures. 相似文献
639.
Moringa oleifera pods Lamarck (Drumstick or Horseradish) is a multipurpose medium or small size tree from sub-Himalayan regions of north-west India and indigenous to many parts of Asia, Africa, South America, and in the Pacific and Caribbean Islands. Its pods (MOP) have been employed as an inexpensive and effective sorbent for the removal of organics, i.e., benzene, toluene, ethylbenzene and cumene (BTEC) from aqueous solutions using HPLC method. Effect of different parameters, i.e., sorbent dose 0.05-0.8g, 25cm(-3) agitation time 5-120min, pH 1-10, temperature 283-308K and concentration of sorbate (1.3-13)x10(-3), (1.1-11)x10(-3), (0.9-9)x10(-3), (0.8-8)x10(-3)moldm(-3), on the sorption potential of MOP for BTEC have been investigated. The pore area and average pore diameter of the MOP by BET method using nitrogen as a standard are calculated to be 28.06+/-0.8m(2)g(-1) and 86.2+/-1.3nm respectively. Freundlich, Langumir and Dubinin-Radushkevich (D-R) sorption isotherms were employed to evaluate the sorption capacity of MOP. Sorption capacities of BTEC onto MOP have been found to be 46+/-10, 84+/-9, 101+/-4, 106+/-32mmolg(-1) by Freundlich, 8+/-0.1, 9+/-0.1, 10+/-0.3, 9+/-0.1mmolg(-1) by Langumir and 15+/-1, 21+/-1, 23+/-2, 22+/-3mmolg(-1) by D-R isotherms respectively, from BTEC solutions at 303K. While the mean energy of sorption process 9.6+/-0.3, 9.2+/-0.2, 9.3+/-0.3, 9.5+/-0.4kJmol(-1) for BTEC is calculated by D-R isotherm only. Rate constant of BTEC onto MOP 0.033+/-0.003, 0.030+/-0.002, 0.029+/-0.002, 0.027+/-0.002min(-1) at solution concentration of 1.3x10(-3), 1.1x10(-3), 0.9x10(-3) and 0.8x10(-3)moldm(-3) and at 303K have been calculated by employing Lagergren equation. Thermodynamic parameters DeltaH -8+/-0.4, -10+/-0.6, -11+/-0.7, -11+/-0.7kJmol(-1), DeltaS -22+/-2, -26+/-2, -27+/-2, -29+/-3Jmol(-1)K(-1) and DeltaG(303K) -0.9+/-0.2, -1.9+/-0.2, -2.3+/-0.1 and -2.6+/-0.2kJmol(-1) were also estimated for BTEC respectively at temperatures 283-308K. The negative values of DeltaH, DeltaS and DeltaG suggest exothermic, stable (with no structural changes at solid-liquid interface) and spontaneous nature of sorption process under optimized conditions. MOP has been used extensively to accrue and then to preconcentrate benzene, toluene and ethylbenzene in wastewater sample. 相似文献
640.
Habermacher FD Napelenok SL Akhtar F Hu Y Russell AG 《Environmental science & technology》2007,41(11):3997-4003
An approach is developed and tested to extend discrete, source-based sensitivity results to provide a complete set of information for source-air quality impacts, including inversion of those results to develop receptor-oriented source-impact sensitivities. First, the decoupled direct sensitivity analysis method in 3D (DDM-3D) is used to calculate a finite number of forward sensitivities from discrete points. These results are then interpolated using tessellation to provide complete fields of forward, emissions-based sensitivities, i.e., how emissions in any one grid cell within the domain impact any other cell. Receptor-oriented sensitivities are then found by inverting the set of forward sensitivities and can be used to identify the area of influence (AOI). This economically provides results similar to what would be found using an adjoint model. The present approach is computationally less intensive than adjoint modeling for a large number of receptors, and provides both source-oriented and receptor-oriented pollutant response fields that can be used for air quality management and health impact analyses. The forward sensitivity interpolation procedure, as well as the receptor-oriented sensitivities, is evaluated using data withholding. 相似文献