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1.
The in vitro drug sensitivity of three dihydrofolate reductase inhibitors (pyrimethamine, cycloguanil, trimethoprim) was determined against 29 strains and isolates of Plasmodium falciparum by an isotopic semi-microtest. Trimethoprim is less active than pyrimethamine or cycloguanil and its activity is correlated with that of two other inhibitors, suggesting cross-resistance in vitro among the dihydrofolate reductase inhibitors. 相似文献
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The miscibility and phase behavior of ternary blends containing dimethylpolycarbonate (DMPC), tetramethylpolycarbonate (TMPC) and poly[styrene‐co‐(methyl methacrylate)] copolymer (SMMA) have been explored. Ternary blends containing polystyrene (PS) instead of SMMA were also examined. Blends of DMPC with SMMA copolymers (or PS) did not form miscible blends regardless of methyl methacrylate (MMA) content in copolymers. However, DMPC blends with SMMA (or PS) blends become miscible by adding TMPC. The miscible region of ternary blends is compared with the previously determined miscibility region of binary blends having the same chemical components and compositions. The region where the ternary blends are miscible is much narrower than that of binary blends. Based on lattice fluid theory, the observed phase behavior of ternary blends was analyzed. Even though the term representing the Gibbs free energy change of mixing for certain ternary blends had a negative value, blends were immiscible. It was revealed that a negative value of the Gibbs free energy change of mixing was not a sufficient condition for miscible ternary blends because of the asymmetry in the binary interactions involved in ternary blends. Copyright © 2004 Society of Chemical Industry 相似文献
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We present a technique for in situ lens nucleus emulsification using low phaco power and high vacuum, a continuous curvilinear capsulorhexis, and hydrodelineation. Emulsification is done with the phaco tip slanted down 30 or 45 degrees. Cutting and aspiration do not cause an undesirable energy loss. This technique can be combined with the nuclear chopping or divide and conquer methods because of its ability to drill and hold the nucleus. Posterior capsular rupture is prevented because the separated epinucleus acts as a barrier between the nucleus and the cortex. The low power used minimizes the energy transfer to the corneal endothelium. This technique is particularly useful in eyes with brunescent cataract. 相似文献
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CK Damer J Partridge WR Pearson TA Haystead 《Canadian Metallurgical Quarterly》1998,273(38):24396-24405
Microcystin-affinity chromatography was used to purify 15 protein phosphatase 1 (PP1)-binding proteins from the myofibrillar fraction of rabbit skeletal muscle. To reduce the time and amount of material required to identify these proteins, proteome analysis by mixed peptide sequencing was developed. Proteins are resolved by SDS-polyacrylamide gel electrophoresis, electroblotted to polyvinylidene fluoride membrane, and stained. Bands are sliced from the membrane, cleaved briefly with CnBr, and applied without further purification to an automated Edman sequencer. The mixed peptide sequences generated are sorted and matched against the GenBank using two new programs, FASTF and TFASTF. This technology offers a simple alternative to mass spectrometry for the subpicomolar identification of proteins in polyacrylamide gels. Using this technology, all 15 proteins recovered in PP-1C affinity chromatography were sequenced. One of the proteins, PP-1bp55, was homologous to human myosin phosphatase, MYPT2. A second, PP-1bp80, identified in the EST data bases, contained a putative PP-1C binding site and a nucleotide binding motif. Further affinity purification over ATP-Sepharose isolated PP-1bp80 in a quaternary complex with PP-1C and two other proteins, PP-1bp29 and human p20. Recombinant PP-1bp80 also bound PP-1C and suppressed its activity toward a variety of substrates, suggesting that the protein is a novel regulatory subunit of PP-1. 相似文献
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The cholesterolaemic effect of 2 hypercholesterolaemic diets was tested in 12 rat inbred strains. Diet I is a commercial diet supplemented with 2.0% (w/w) cholesterol and 5.0% (w/w) olive oil; diet II is identical to diet I with addition of 0.5% (w/w) sodium cholate. Strains with the highest plasma cholesterol response after diet I (BN and LEW) also had the highest cholesterol response after diet II (hyperresponders, mean response > 3.5 mmol/l). In the strains DA, SHR, BC, WAG, LOU, PVG and BUF the strain mean cholesterol response remained below 1.3 mmol/l after both diets (hyporesponders). Strains F344 and OM had an intermediate cholesterol response after both diets (normoresponders, mean response between 1.3 and 3.5 mmol/l). Only in the strains LOU, PVG and SHR there appeared to be a significant higher cholesterol response after diet II when compared with the cholesterol response after diet I. In the strain WKY this difference was of a borderline significance (P = 0.052) and this strain turned from a normoresponder after diet I into a hyperresponder after diet II. Liver cholesterol levels as measured after feeding diet II for two weeks also appeared to be strain-specific. No correlation was found between the plasma cholesterol response after diet II and the liver cholesterol levels. Changes in plasma phospholipid and triglyceride levels have been measured for both diet I and diet II. For group means a correlation between the cholesterol response and the change in phospholipid levels was found (r = 0.86 for diet I, P < 0.001 and r = 0.76 for diet II, P < 0.01). No such correlation was found for triglyceride levels. 相似文献
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Pressure-sensitive acrylic adhesives for application to skin are made from 2-ethylhexyl acrylate, isooctyl acrylate or n-butyl acrylate copolymerized with polar functional monomers such as acrylic acid, methacrylic acid, vinyl acetate, methyl acrylate, N-vinylcaprolactam, or hydroxyethyl methacrylate. Functional comonomers increase cohesive strength, provide surface polarity, and enhance wear performance. Tack, adhesion to skin, adhesive transfer to skin, and wear performance of the adhesive are governed by the molecular weight, glass transition temperature, and the viscoelastic behavior of the adhesive. Viscoelastic properties of the adhesive as measured by the Williams plasticity number (WPN), dynamic storage modulus (G′), dynamic loss modulus (G″), and tan δ are important polymer properties for good wear performance. Sweating skin, a moist environment, and physical activity are the most important factors influencing the failure of an adhesive tape during wear. A medicalgrade adhesive for application to human skin should be hypoallergenic. Medical-grade adhesives are utilized in making surgical tapes for holding dressings in place, adhesive bandages, adhesive dressings to cover wounds, and surgical operating drapes. 相似文献
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WS Ahn J Yoo SW Huh CK Kim JM Lee SE Namkoong SM Bae IP Lee 《Canadian Metallurgical Quarterly》2003,12(5):383-390
We investigated clinical efficacy of green tea extracts (polyphenon E; poly E and (-)-epigallocatechin-3-gallate [EGCG]) delivered in a form of ointment or capsule in patients with human papilloma virus (HPV) infected cervical lesions. Fifty-one patients with cervical lesions (chronic cervicitis, mild dysplasia, moderate dysplasia and severe dysplasia) were divided into four groups, as compared with 39 untreated patients as a control. Poly E ointment was applied locally to 27 patients twice a week. For oral delivery, a 200 mg of poly E or EGCG capsule was taken orally every day for eight to 12 weeks. In the study, 20 out of 27 patients (74%) under poly E ointment therapy showed a response. Six out of eight patients under poly E ointment plus poly E capsule therapy (75%) showed a response, and three out of six patients (50%) under poly E capsule therapy showed a response. Six out of 10 patients (60%) under EGCG capsule therapy showed a response. Overall, a 69% response rate (35/51) was noted for treatment with green tea extracts, as compared with a 10% response rate (4/39) in untreated controls (P<0.05). Thus, the data collected here demonstrated that green tea extracts in a form of ointment and capsule are effective for treating cervical lesions, suggesting that green tea extracts can be a potential therapy regimen for patients with HPV infected cervical lesions. 相似文献
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