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91.
A total of 29 patients with stage IV colorectal cancer were entered into a phase II trial of bolus interleukin-2 (IL-2) and interferon-alpha (IFN alpha) (3 x 10(6) U/m2 of each cytokine given i.v. q8h x 15 doses and repeated in 2 weeks). Immunologic parameters measured on isolated peripheral blood lymphocytes revealed increased activated T cells with upregulated natural killer and lymphokine-activated killer activity. Among 24 evaluable patients, there were 4 partial responses (17%) of short duration ( < or = 6 months). Three of the responding patients had been refractory to prior chemotherapy. Overall median survival in the 24 evaluable patients was 18.5 months. Therapy necessitated an inpatient setting, with the most common toxicities being hypotension, hepatic insufficiency, fever, hypocalcemia, nausea/vomiting, and renal insufficiency. There were two treatment-related deaths. Because neither IL-2 nor IFN alpha alone has significant activity against colorectal cancer, the responses observed in this study suggest a potential synergistic effect between the two cytokines. However, the toxicity and short duration of response without survival benefit do not support the routine use of this regimen as a therapeutic modality for this tumor histology.  相似文献   
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Chronic action of different xenobiotics which form a part of condensed hydrogen sulphide-containing gas causes substantial changes in the activity of xenobiotic metabolic enzymes, which is suggestive of the damaged hepatic microsomal monooxygenase system. As the rate of biotransformation becomes higher, there are increases in the activity of microsomal monooxygenases and in the generation of active oxygen forms and hydrogen peroxide, by impairing antiradical and antiperoxide mechanisms. The experimentally used concentration of substances as constituents of condensed gas corresponds to the maximum acceptable air concentration of in the working area of gas-refining plants, but the functional features of the body's detoxifying system--the hepatic monooxygenase system should be taken into account while developing preventive measures of occupational diseases.  相似文献   
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With an increasing requirement to classify traffic and track security threats, newer flexible and efficient ways are needed for collecting traffic statistics and monitoring network flows. However, traditional solutions based on packet sampling do not provide the flexibility required for these applications. For example, operators are often interested in observing as many unique flows as possible; however, random packet sampling is inherently biased towards large flows. Operators may also be interested in increasing the fidelity of flow measurements for a certain class of flows; such flexibility is lacking in today’s packet sampling frameworks. In this paper, we propose a novel architecture called CLAMP that provides an efficient framework to implement class-based sampling. At the heart of CLAMP is a novel data structure we propose called composite Bloom filter (CBF) that consists of a set of Bloom filters working together to encapsulate various class definitions. In particular, we show the flexibility and efficacy of CLAMP by implementing a simple two-class size-based sampling. We also consider different objectives such as maximizing flow coverage and improving the accuracy of certain class of flows. In comparison to previous approaches that implement simple size-based sampling, our architecture requires substantially lower amounts of memory (up to 80×) and achieves higher flow coverage (up to 8× more flows) under specific configurations.  相似文献   
95.
The effect of technology scaling (0.5-0.09 /spl mu/m) on single event upset (SEU) phenomena is investigated using full two-dimensional device simulation. The SEU reliability parameters, such as critical charge (Q/sub crit/), feedback time (T/sub fd/) and linear energy transfer (LET), are estimated. For L/sub g/<0.18 /spl mu/m, the source node collects a significant fraction of radiation-induced charge resulting in an increase of LET, despite the lower critical charge at the sensitive drain node. The effect of striking location on LET confirms this finding.  相似文献   
96.
A few aluminum containing polycarbosilanes named AlOR-PCS and Alac-PCS have been synthesized by the reaction of aluminum isopropoxide (AlOR) and aluminum acetylacetonate (Alac) with polycarbosilane (PCS), respectively. These materials were characterized by Fourier Transform Spectroscopy (FTIR), Thermo gravimetric Analysis (TGA) and Gel Permeation Chromatography (GPC). The rheological properties of these compounds were studied with respect to time, temperature and atmosphere (inert & air). It has been observed that the increase in metal content enhances the crosslinking of the PCS chains. Under similar conditions, the crosslinking of AlOR-PCS derivatives was found slower than Alac-PCS. GPC analysis of the samples showed the increase in molecular weight of these compounds compared to virgin PCS. TGA showed improved ceramic yield with increasing metal content. Alac-PCS gave higher ceramic yield than AlOR-PCS for similar molar ratios of metal complexes.  相似文献   
97.
Yogi  Priyanka  Poonia  Deepika  Yadav  Pooja  Mishra  Suryakant  Saxena  Shailendra K.  Roy  Swarup  Sagdeo  Pankaj R.  Kumar  Rajesh 《SILICON》2018,10(6):2801-2807
Silicon - Nano-metal/semiconductor junction dependent porosification of silicon has been studied here. The silicon nanostructures (SiNSs) have been textured on n- and p- type silicon wafers using...  相似文献   
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Fracture toughness tests were conducted on a Ti-62222 (titanium alloy) sheet being considered for use in high temperature aircraft applications in the as received condition and after exposing the pre-cracked specimens to a sustained stress intensity, K, level between 55 and 60.5 MPa for 200 h at 350°C. It was concluded that the fracture toughness does not degrade as a result of exposure to high temperature and the K levels in this material. The tensile strength in the exposed condition also remained the same as in the as received condition.  相似文献   
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