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111.
H Matsuda T Kusakabe Y Hayashida M Furukawa T Kawakami T Takenaka M Tsukuda 《Canadian Metallurgical Quarterly》1998,45(6):563-569
Changes made in 1997 and 1998 in the U.S. childhood immunization schedule are discussed, with a focus on the use of poliovirus, pertussis, and combination vaccines. Oral poliovirus vaccine (OPV), the vaccine of choice for all four doses in the polio immunization series since 1962, can cause vaccine-associated paralytic poliomyelitis (VAPP). The inactivated poliovirus vaccine (IPV) has not been associated with VAPP but must be administered by injection and provides inferior intestinal immunity. With the reduced threat of poliovirus importation into the United States, the risk of VAPP, although low, has become less acceptable. The Centers for Disease Control and Prevention accordingly recommended a shift from OPV to IPV in the childhood immunization schedule for the United States, effective January 1997. A sequential OPV and IPV series is recommended, but the schedule includes an OPV-only option, which may be preferred in order to avoid the required injections, and an IPV-only option, which is recommended for immunocompromised persons and their contacts. Concern over local and systemic reactions associated with whole-cell pertussis vaccines, in addition to controversy over a possible relationship between the whole-cell vaccine and neurologic damage, has led to the development of new diphtheria and tetanus toxoids and acellular pertussis vaccine products for use in the diphtheria and tetanus toxoids and pertussis immunization series. Several combination products were licensed in 1997, and more are on the way. This will mean fewer inoculations for children. Increased use of IPV and acellular pertussis products could reduce the frequency of VAPP due to OPV and the local and systemic reactions associated with whole-cell pertussis vaccine. 相似文献
112.
M Matsuda S Ota R Tanimura H Nakamura K Matuoka T Takenawa K Nagashima T Kurata 《Canadian Metallurgical Quarterly》1996,271(24):14468-14472
CRK is a human homolog of chichen v-Crk, which is an adaptor protein. The SH2 domain of CRK binds to several tyrosine-phosphorylated proteins, including the epidermal growth factor receptor, p130(Cas), Shc, and paxillin. The SH3 domain, in turn, binds to cytosolic proteins of 135-145, 160, 180, and 220 kDa. We screened expression libraries by Far Western blotting, using CRK SH3 as a probe, and identified partial cDNA sequences of four distinct proteins, including C3G, DOCK180, EPS15, and clone ST12. The consensus sequence of the CRK SH3 binding sites as deduced from their amino acid sequences was Pro+3-Pro+2-X+1-Leu0-Pro-1-X-2-Lys-3. The interaction of the CRK SH3 domain with the DOCK180 peptide was examined with an optical biosensor, based on the principles of surface plasmon resonance. A low dissociation constant of the order of 10(-7) resulted from a high association rate constant (kassoc = 3 x 10(4)) and low dissociation rate constant (kdiss = 3 x 10(-3)). All CRK-binding proteins except clone ST12 also bound to another adaptor protein, Grb2. Mutational analysis revealed that glycine at position +1 of ST12 inhibited the binding to Grb2 while retaining the high affinity binding to CRK SH3. The result suggests that the amino acid at position +1 also contributes to the high affinity binding of the peptides to the SH3 domain of Grb2, but not to that of CRK. 相似文献
113.
Removal of selected pharmaceuticals by chlorination, coagulation-sedimentation and powdered activated carbon treatment 总被引:2,自引:0,他引:2
D Simazaki J Fujiwara S Manabe M Matsuda M Asami S Kunikane 《Water science and technology》2008,58(5):1129-1135
Removal property of nine pharmaceuticals (clofibric acid, diclofenac, fenoprofen, gemfibrozil, ibuprofen, indomethacin, ketoprofen, naproxen and propyphenazone) by chlorination, coagulation-sedimentation and powdered activated carbon treatment was examined by laboratory-scale experiments under the conditions close to actual drinking water treatment processes. Indomethacin and propyphenazone were completely degraded by chlorination within 30 minutes, but others remained around 30% (naproxen and diclofenac) or more than 80% of the initial concentration after 24 hours. A couple of unidentified peaks in a chromatogram of the chlorinated samples suggested the formation of unknown chlorination by-products. Competitive adsorption was observed when the mixed solution of the target pharmaceuticals was subjected to batch adsorption test with powdered activated carbon. Clofibric acid and ibuprofen, which were relatively less hydrophobic among the nine compounds, persisted around 60% of the initial concentration after 3 hours of contact time. Removal performance in actual drinking water treatment would become lower due to existence of other competitive substances in raw water (e.g. natural organic matter). Coagulation-sedimentation using polyaluminium chloride hardly removed most of the pharmaceuticals even under its optimal dose for turbidity removal. It is suggested that the most part of pharmaceuticals in raw water might persist in the course of conventional drinking water treatments. 相似文献
114.
Tiesheng Li Shuji Okada Hirohito Umezawa Hitoshi Kasai Hachiro Nakanishi Satya S. Talwar Tatsumi Kimura Hiro Matsuda 《Polymer Bulletin》2006,57(5):737-746
Summary 1,4-Bis(3-quinolyl)-1,3-butadiyne (DQ) is known to be polymerized in solid state to give the corresponding polydiacetylene.
However, the polymer yield of DQ bulk crystals is low. Thus, we prepared several types of DQ crystals by different procedures
to find the reason for the low polymer yield. We found three modifications of DQ crystals and they were evaluated by spectroscopic
measurements and X-ray diffraction. DQ bulk crystals (Crystal I) and thermally grown DQ crystals on Crystal I (Crystal II)
have the same structure classified to Type A, which gives regular polydiacetylene structure in low polymer yields. DQ crystals
grown on glass plates by sublimation (Crystal III) belong to the second modification of Type B. DQ nanocrystals prepared by
the reprecipitation method (Crystal IV) are Type B, and thermally grown DQ crystals on nanocrystals (Crystal V) are Type C.
Crystals of Types B and C could be polymerized in low yields without showing excitonic absorption of polydiacetylene indicating
irregular polymerization other than 1,4-addition. For crystals of Type A, we found that the 1,4-addition polymerization proceeded
only in near-surface portions of the crystals. It can be plausibly explained that mobile monomers in the near-surface portion
are only able to take part in their polymerization, resulting in low polymer conversion. 相似文献
115.
An approximate method is developed to study the static bending of shallow shells with variable thickness. The solutions are obtained by transforming the partial differential equations into the integral equations and applying the numerical integrations. Some numerical examples are shown together with other solutions, and as an application of this method, the results of shallow shell with variable thickness are shown. 相似文献
116.
Goto H. Ohkubo H. Kondou K. Ohkawa M. Mitano H. Horiba S. Soeda M. Hayashi F. Hachiya Y. Shimizu T. Ando M. Matsuda Z. 《Solid-State Circuits, IEEE Journal of》1992,27(11):1490-1496
A 16-Mb CMOS SRAM having an access time of 12 ns under a 3.3-V supply has been developed with a 0.4-μm process technology. An address access time of 12 ns has been achieved by an optimized architecture, the use of an automated transistor size optimizer, and a read-bus midlevel preset scheme (RBMIPS). For better yield and efficient testing, an on-chip test circuit with three test modes has been implemented 相似文献
117.
118.
This study aimed to develop a quantitative assay method of determining cellular events at the mRNA level during tissue formation. Quantitative assessment of mRNAs coding specific proteins (beta-actin, fibronectin, laminin) during tissue formation on tissue culture dishes was attained using a Northern blot technique with autoradiography. The amount of beta-actin mRNA, the expression of which is initiated shortly after adhesion, greatly increased with incubation time and reached maximal levels near the confluent state, followed by a reduced expression at a later stage of tissue formation. The time course of beta-actin mRNA expression, which reflects cytoskeletal organization, corresponded well to morphologic changes in adherent cells. Expression of mRNAs coding the extracellular matrix proteins, fibronectin and laminin, was initiated at the proliferation stage. After maximum expression levels were observed at the confluent stage, a gradual decrease in the expression of both mRNAs was seen after longer culture periods. Expression patterns of mRNAs coding cytoskeletal and extracellular matrix proteins greatly depended upon the type of artificial substrates. Thus, the dynamic changes in tissue formation were quantified to elucidate the significance of artificial substrates in tissue formation at the mRNA level. 相似文献
119.
Y Miura M Ueda Y Kondou H Yamasaki A Takami N Sugimori M Saito S Nakao S Shiohara K Saito T Matsuda 《Canadian Metallurgical Quarterly》1997,38(6):526-531
Matrix metalloproteinases have been shown to be important in tumour invasion and metastasis, and the use of matrix metalloproteinase inhibitors in animal models has suggested that these agents may be useful in the control of malignant disease. This article reports the results of an early clinical trial of batimastat, one of the first generation of metalloproteinase inhibitors, in patients with malignant ascites. The drug was well absorbed via the intraperitoneal route and associated with few side-effects. Furthermore, a response to treatment was seen in about half the evaluable patients with advanced malignant disease. The results suggest that further research on the use of matrix metalloproteinase inhibitors in patients with malignant disease is worthwhile. 相似文献
120.
The OMDR (optical-microwave double resonance) effect in the Cs D 2 line was studied for realizing a gas-cell-type Cs atomic frequency standard. A glass cell containing Cs with buffer gases (Ar/N2=1.26, total pressure=39 torr) was placed in a TE012 mode microwave cavity at a temperature of 45°C and was pumped using a GaAs semiconductor laser frequency locked to an external interferometer tuned to the 6P3/2 (F=2,3,4)←6 S 1/2(F =3) transition. The OMDR signal appearing at the resonance to the F =4←3 hyperfine transition of the 6S1/2 state shifted with detuning of the laser frequency and with change of the laser and microwave powers. The dependence of the shift on these variables around an optimum operating condition was obtained as, ΔνMW[Hz]=-(0.31±0.02) {1+(0.44±0.15) (ΔP L/P L)} ΔνL [MHz]-10(ΔV MW/V MW) 相似文献