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91.
Ki-1 large cell anaplastic lymphoma is a recently described variant of malignant lymphoma. A retrospective study of 10 cases of Ki-1 lymphoma was carried out at the Armed Forces Institute of Pathology (AFIP) Rawalpindi to document its clinical and morphological features. The morphological features were evaluated by a study of paraffin embedded sections stained with haematoxylin and eosin stains. Immunohistochemical stains for BER-H2 and leucocyte common antigen (LCA) were performed in all cases. The age of the patients ranged from 2 to 60 years and male to female ratio was 2.3:1. Cervical lymphadenopathy was the most common presentation. Histologically, there was a complete effacement of the lymph node architecture in 8 cases. The Reed-Sternberg like cells were seen in 2 and histiocyte like cells in 7 cases. Immunohistochemically all cases were positive for BER-H2. It is suggested that the possibility of Ki-1 lymphoma should be considered in all cases of lymphoma with pleomorphic morphology.  相似文献   
92.
93.
Coker light gas oil (LGO) derived from Athabasca bitumen was hydrotreated in a fixed bed reactor using two commercial NiO-MoO3/Al203 catalysts. The effect of temperature on product quality was investigated in a pilot plant between 330 and 390 °C at 12.4 MPa, space velocity of 0.5 Ir1 and 700 liter of hydrogen per liter of coker LGO (L/L). The product quality was monitored by I3C NMR spectroscopy, elemental analysis, density and distillation techniques.

The data showed that coker LGO can be hydrotreated using nickel-molybdenum catalysts at 350 °C, 0.5 h1, 12.4 MPa and 700 L/L to meet the diesel product specifications, namely, 0.5 wt % sulfur, 20% aromatics and cetane index of 40. The cetane index improvement and aromatic saturation, which are affected by thermodynamic equilibrium at temperature higher than 370 °C, could reach 29 and 86% respectively. The cetane improvement was attributed to aromatic saturation and hydrocracking with hydrogen consumption ranging from 215-340 L/L. The Ketjenfine KF-840 catalyst was found slightly better performance than Procatalyse HR-348 catalyst.  相似文献   
94.
This paper presents novel and highly effective junction isolation structures for power integrated circuits. The negative feedback-activated junction isolation is presented and it is proven to be very effective in blocking substrate current from reaching the logic circuitry (orders of magnitude more effective than standard junction isolation techniques). Additionally, in an attempt to further improve the blocking capabilities of junction isolations the use of multiple or combined structures is investigated whilst keeping the surface area used for isolation device in the same range as for the single structures. All isolation structures presented here are based on a 0.6-/spl mu/m CMOS technology.  相似文献   
95.
The general corrosion behaviour of low residual steels alloyed with chromium or cobalt or molybdenum in seawater solutions was studied. The carbon content of low residual steels ranged from 0.1 to 0.4%, chromium content between 1.0 and 4.0%, cobalt content between 1.0 and 3.0%, and molybdenum content between 0.3 and 1.0%. Repeated laboratory tests demonstrated that low levels of chromium reduce the dissolution rate of low residual steels in seawater solutions. The results of this study suggest that cobalt alloying plays a neutral role, whereas molybdenum plays a major role in reducing the corrosion rates, particularly in higher carbon steels.  相似文献   
96.
Jamal Khan   《Thin solid films》1992,220(1-2):222-226
A lapping process for achieving high quality alumina (Al2O3) surfaces was investigated. Alumina films were sputter deposited on thick TiC---Al2O3 ceramic wafers. Polishing of these films was carried out on pitch plates (organic resin melted and set on the circular disk of a lapping machine). Abrasives with different grit sizes, 0.05–1.0 μm, were tried together with different lapping process parameters. Qualitu of the lapped surface was studied in terms of roughness and flatness. Stock removal rates were also measured. Correlation of surface quality with lapping parameters was established to achieve process optimization.

Scratch-free polished alumina surfaces were obtained by using this technique. Specific applications of the process in the fabrication of magnetic recording devices are indicated.  相似文献   

97.
98.
This paper presents the development of a multipurpose simulator with the general model describing a four-component, three-phase (oil, aqua, gas), multi-dimensional, finite-difference polymer injection simulator. The model uses a block-centered grid and a seven-point finite-difference scheme. Fluid saturations and pressure distributions are obtained from a fully implicit formulation using Newton's method, whereas polymer concentration is obtained, in a subsequent step, explicitly using the method of cascade. Practical features of the present simulator include: (1) a truly multipurpose simulation; and (2) ease of preparing a batch data file required for the simulator. A novel and simple procedure is implemented to reduce the general model of the polymer injection simulator (polymer, oil, aqua, and gas) to: (1) three-phase black-oil simulator (oil, water, and gas); (2) two-phase black-oil simulators (oil and water, oil and gas, or water and gas); (3) two-phase polymer injection simulator (polymer, oil, and aqua); and (4) one-phase simulators (oil, water, or gas) with only the relevant equations being solved at the matrix level for each simulator. Guidelines for other practical features are also presented.The simulator was tested and verified using a polymer injection test problem and a gas injection bench mark test problem both reported in the literature. The simulator was also used to model a field case and some results are highlighted.  相似文献   
99.
Allogeneic peripheral blood progenitor cell (PBPC) transplants are an alternative to BMT, although G-CSF mobilization dose, timing of pheresis and risk of GVHD are not well defined. We compared harvest characteristics, donor and recipient outcomes and costs of two PBPC transplant strategies with historical controls who received BMT. Twenty donors mobilized with four daily s.c. G-CSF doses (5 microg/kg/day) (group 1) and 20 mobilized with 10 microg/kg/day G-CSF (group 2) were compared with 20 BM controls (group 3). G-CSF and phereses were well tolerated. Four of 40 PBPC donors required femoral catheter placement. At least 2.5 x 10(6) CD34+/kg recipient weight were collected with two phereses in 19/20 donors (group 1) and 18/20 donors (group 2). Time to neutrophil (18 vs 20 vs 22 days, P = 0.02) and platelet (21 vs 24 vs 27 days, P = 0.005) engraftment was shorter in the PBPC groups (group 2 vs group 1 vs group 3) but secondary engraftment outcomes were not different. The incidence of grade 2-4 aGVHD was higher in the low-dose G-CSF group (group 1) but there was no difference in cGVHD, 100-day or 1-year survival. The mean PBPC transplant cost (group 1) at first hospital discharge was less than BM (group 3) ($34,643 vs $37,354) but the mean overall cost for both groups was similar at 100 days ($46,334 vs $46,083). Allogeneic PBPC transplant with short course, low-dose G-CSF mobilization is safe, feasible and cost equivalent to allogeneic BMT.  相似文献   
100.
Thegem-dibromocyclopropanation of naturally occurring unsaturated hydroxy fatty esters, methyl ricinoleate (I) and methyl isoricinoleate (II), has been undertaken to provide compounds which might have potential utility. Phenyl(tribromomethyl)mercury reacts only with the carbon-carbon double bond of each substrate, leaving the OH group intact. The product, methyl 9,10-dibromomethylene-12-hydroxyoctadecanoate (III) and methyl 12,13-dibromomethylene-9-hydroxyoctadecanoate (IV), obtained from I and II, respectively, were characterized by elemental, infrared (IR) and nuclear magnetic resonance (NMR) analyses.  相似文献   
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