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91.
In this study a series of 3-arylisoquinoline derivatives were synthesized and cytotoxicity against human melanoma tumor cell evaluated, and a three dimensional quantitative structure-activity relationship was investigated using the comparative molecular field analysis (CoMFA). The results suggested that the electrostatic, steric and hydrophobic factors of 3-arylisoquinolines were strongly correlated with the antitumor activity. Considerable predictive ability (cross-validated r2 as high as 0.721) was obtained through CoMFA.  相似文献   
92.
OBJECTIVE: To investigate the effect of diphtheria toxin interleukin 2 recombinant fusion protein (DAB 486IL-2) on in vitro synthesis of immunoglobulin and rheumatoid factor (RF) in patients with severe refractory rheumatoid arthritis (RA) enrolled in a phase II, double blind, placebo controlled study. METHODS: Anticoagulated venous blood samples were obtained before (Day 1) and after (Day 28) intravenous infusion of either DAB 486IL-2 at 0.075 mg/kg/day (12 patients) or saline placebo (10 patients) on Days 1-5. Peripheral blood leukocytes (PBL) were prepared by density gradient centrifugation, cultured in the presence and absence of pokeweed mitogen (PWM) for one week, and culture supernatants assayed for immunoglobulins and IgM RF by ELISA. RESULTS: Compared to placebo treated patients, PWM induced IgM RF synthesis by PBL decreased after treatment with DAB 486IL-2 (p = 0.043). However, there was no apparent correlation with clinical improvement. PWM induced IgM, IgA, and IgG synthesis also tended to decrease, although the changes did not attain statistical significance. In contrast, PWM induced IgM RF, IgM, IgA, and IgG synthesis by PBL from patients treated with placebo tended to increase during the observation period. Spontaneous immunoglobulin and IgM RF production by PBL from either the DAB 486IL-2 or placebo patients remained stable. CONCLUSION: These observations raise the possibility that DAB 486IL-2 may diminish B cell function either directly or indirectly through effects on T cell function, but the change may not correspond to clinical response.  相似文献   
93.
OBJECTIVE: To determine whether neoadjuvant chemotherapy and radiotherapy for bony sarcomas extending into soft tissues would allow limb salvage yet maintain local disease control. DESIGN: A prospective cohort study. SETTING: A university-affiliated cancer centre in Alberta. PATIENTS: All patients with potentially curable, widely infiltrating bony sarcomas of the extremity without neurologic deficit, referred to the centre in the 6 years from January 1984 to December 1990. There were 11 patients; 1 did not complete the protocol. The mean follow-up was 24 months. INTERVENTIONS: Adriamycin (doxorubicin) was infused for 3 days at a rate of 30 mg/d. A few days later radiotherapy was given 5 days a week for 10 doses at a rate of 3.0 Gy per dose. Four to 5 weeks later the tumour was excised surgically, with placement of a bone allograft or prosthesis, allowing a 1-cm margin of healthy soft tissue and a 5-cm margin of healthy bone and marrow cavity whenever possible. MAIN OUTCOME MEASURES: Need for limb amputation, infectious complications, recurrence of local or regional disease. RESULTS: One patient underwent amputation after fracture through the tumour site. There were two postoperative infections, one acute and one chronic. All patients had full neurologic function of the distal limb. There was no local or regional recurrence of disease. CONCLUSION: Neoadjuvant chemotherapy followed by radiotherapy and tumour excision provides control of aggressive local bone sarcomas while maintaining limb integrity.  相似文献   
94.
A smart home usually has a variety of devices or home appliance, instead of designing software for a specific home, this paper proposes a service-oriented framework with a set of ontology systems to support service and device publishing, discovery of devices and their services, composition of control software using existing control services that wrap devices, deployment, and execution of the composed service in an computing environment, monitoring the execution, and recovery from device failure. The ontology systems specify semantic information about devices, services, and workflows used in various smart home, and users can compose and recompose services for their specific needs. New devices, workflows, and services can be added into ontology. Most of the steps in this process can be automated including code generation. For example, service composition will be carried out in three steps: abstract workflow design, function construction, and device discovery, and different codes can be generated for different computing platforms such as Java and Open Services Gateway initiative environments. In this way, a variety of smart home can be constructed rapidly using the framework by discovery and composition using existing services and workflows. This paper illustrates this framework using a media control example to illustrate the ontology, discovery, composition, deployment, execution, monitoring, and recovery.  相似文献   
95.
in this paper, simple 1-D and 2-D systolic array for realizing the discrete cosine transform (DCT) based on the discrete Fourier transform (DFT) fo an input sequence are presented. The proposed arrays are obtained by a simple modified DFT (MDFT) and an inverse DFT (IDFT) version of the Goertzel algorithm combined with Kung's approach. The 1-D array requiresN cells, one multiplier and takesN clock cycles to produce a completeN-point DCT. The 2-D array takes N clock cycles, faster than the 1-D array, but the area complexity is larger. A continuous flow of input data is allowed and no idle time is required between the input sequences.  相似文献   
96.
The role of the blood–brain barrier (BBB) breakdown has been recognized as being important in Alzheimer’s disease pathogenesis. We aimed to evaluate whether regional BBB integrity differed according to sex and whether differences in BBB integrity changed as a consequence of aging or cognitive decline, using dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI). In total, 75 participants with normal cognition (NC) or mild cognitive impairment (MCI) underwent cognitive assessments and MRI examination including DCE-MRI. Regional Ktrans was calculated in cortical regions and the Patlak permeability model was used to calculate BBB permeability (Ktrans, min−1). Females had a lower median Ktrans in the cingulate and occipital cortices. In the “older old” group, sex differences in Ktrans were only observed in the occipital cortex. In the MCI group, sex differences in Ktrans were only observed in the occipital cortex. Age was the only predictor of cognitive assessment scores in the male MCI group; however, educational years and Ktrans in the occipital cortex could predict cognitive scores in the female MCI group. Our study revealed that females may have better BBB integrity in cingulate and occipital cortices. We also found that sex-related differences in BBB integrity are attenuated with aging or cognitive decline.  相似文献   
97.
The objective of this study was to investigate the effects of supplementing with L-tryptophan (L-Trp) on milk protein synthesis using an immortalized bovine mammary epithelial (MAC-T) cell line. Cells were treated with 0, 0.3, 0.6, 0.9, 1.2, and 1.5 mM of supplemental L-Trp, and the most efficient time for protein synthesis was determined by measuring cell, medium, and total protein at 0, 24, 48, 72, and 96 h. Time and dose tests showed that the 48 h incubation time and a 0.9 mM dose of L-Trp were the optimal values. The mechanism of milk protein synthesis was elucidated through proteomic analysis to identify the metabolic pathway involved. When L-Trp was supplemented, extracellular protein (medium protein) reached its peak at 48 h, whereas intracellular cell protein reached its peak at 96 h with all L-Trp doses. β-casein mRNA gene expression and genes related to milk protein synthesis, such as mammalian target of rapamycin (mTOR) and ribosomal protein 6 (RPS6) genes, were also stimulated (p < 0.05). Overall, there were 51 upregulated and 59 downregulated proteins, many of which are involved in protein synthesis. The results of protein pathway analysis showed that L-Trp stimulated glycolysis, the pentose phosphate pathway, and ATP synthesis, which are pathways involved in energy metabolism. Together, these results demonstrate that L-Trp supplementation, particularly at 0.9 mM, is an effective stimulus in β-casein synthesis by stimulating genes, proteins, and pathways related to protein and energy metabolism.  相似文献   
98.
Hydrogels are recognized as one of the most promising materials for e-skin devices because of their unique applicable functionalities such as flexibility, stretchability, biocompatibility, and conductivity. Beyond the excellent sensing functionalities, the e-skin devices further need to secure a target-oriented 3D structure to be applied onto various body parts having complex 3D shapes. However, most e-skin devices are still fabricated in simple 2D film-type devices, and it is an intriguing issue to fabricate complex 3D e-skin devices resembling target body parts via 3D printing. Here, a material design guideline is provided to prepare multifunctional hydrogels and their target-oriented 3D structures based on extrusion-based 3D printing. The material design parameters to realize target-oriented 3D structures via 3D printing are systematically derived from the correlation between material design of hydrogels and their gelation characteristics, rheological properties, and 3D printing processability for extrusion-based 3D printing. Based on the suggested material design window, ion conductive self-healable hydrogels are designed and successfully applied to extrusion-based 3D printing to realize various 3D shapes.  相似文献   
99.
Measurements of non-methane hydrocarbons (NMHC) were performed at the entrance and exit of the Sangdo tunnel to estimate emission factors (EF) of NMHC from vehicles in May 2000. About 50 species were analyzed by a combined GC/FID and GC/MS system. Ethylene was the most abundant compound, followed by n-butane and acetylene, respectively. Based on the measurement data, the real world vehicular EF in Seoul was estimated. The highest EF value was 89.8 mg (veh-mile)-1 for n-butane, followed by ethylene and toluene.  相似文献   
100.
Well-defined Ln2Sn2O7 powders (Ln = La, Sm and Gd) with a phase-pure pyrochlore structure were synthesized by hydrothermal reaction. The catalytic activities of Ln2Sn2O7 powders for methane combustion were measured. Methane oxidation started at 500 °C and increased with oxidation temperature. Catalytic methane combustion is strongly influenced by the presence of oxygen vacancies that form by breaking Sn–O lattice bonds as the temperature increases. Addition of manganese to the rare earth pyrochlores improved methane oxidation activity. Manganese-doped samarium stannate pyrochlore (Sm2Sn1.8Mn0.2O7) shows highest the catalytic activity. Light-off and complete oxidation temperatures were measured at about 400 and 650 °C, respectively.  相似文献   
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