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排序方式: 共有690条查询结果,搜索用时 15 毫秒
91.
LIM-kinase 1 (LIMK1) and 2 (LIMK2) are members of a novel class of protein kinases containing two LIM motifs at the N-terminus. The LIM motif is thought to be involved in protein-protein interactions. We report here evidence that LIMK1 self-associates and also associates with LIMK2. In vivo and in vitro binding analyses using variously deleted mutants of LIMKI revealed that the self-association of LIMK1 was caused by interaction between the N-terminal LIM domain and the C-terminal kinase domain. The association of LIMK1 with itself and with LIMK2 is important for understanding how activities and functions of LIMK family kinases are regulated. 相似文献
92.
S Kakizaki N Ohya T Yoshinaga T Higuchi R Kitazawa H Takayama H Takagi T Nagamine M Mori 《Canadian Metallurgical Quarterly》1998,28(9):563-566
We present a case of undifferentiated pancreatic cancer associated with humoral hypercalcemia of malignancy (HHM) in which parathyroid hormone-related protein (PTH-rP) is identified as the causative factor of hypercalcemia. A 61-year-old man was hospitalized with right hypochondralgia. Ultrasound examination and computed tomography demonstrated a large mass in the pancreatic head with liver metastases. Biopsy of the pancreatic tumor demonstrated undifferentiated carcinoma. Serum calcium level and PTH-rP were elevated. Bone scan with technetium-99 demonstrated no accumulation in the bones. Immunohistochemical staining for PTH-rP was weakly positive in the tumor cells. We considered that PTH-rP was the causative factor of HHM in this case from laboratory data and immunohistochemical findings. This rare case was successfully treated with pamidronate disodium, which is a type of bisphosphonate derivative. We compared this case with previously reported cases. 相似文献
93.
94.
Ichinose Susumu Matsuki Makoto Higuchi Kazuhito 《Industry Applications, IEEE Transactions on》1985,(1):47-52
A new solid-state scanning ink jet recording technique, called slit jet recording, is proposed. This technique uses a recording head with one slitlike ink-issuing opening having a number of recording electrodes arrayed along a horizontal scanning direction. The ink is emitted from the ink-issuing opening due to the electrical potential difference between a driven recording electrode and a counterelectrode located behind the recording paper. The ink strikes the paper and forms a recording dot. Many recording electrodes can be driven simultaneously by video signals which enhance the total copy recording speed over that for conventional techniques using a single nozzle. The head of this ink jet recording apparatus is remarkably simple in construction and can be fabricated without difficulty. Improvements in reliability and maintainability can also be expected, as the simple structure of the ink-issuing opening reduces clogging and facilitates easy cleaning as compared with other equipment having a large number of nozzles. The recording principle and characteristics and ink-issuing characteristics are described, and the results of a trial recording are presented. The results show that an ISO A4 size (210 mm x 297 mm) full-color copy can be recorded in about 30 s at an 8-dot/ mm rate. 相似文献
95.
S Hiraga N Arita T Ohnishi S Izumoto T Taki M Higuchi K Iwaisako S Sakoda Y Yamamoto T Hayakawa 《Canadian Metallurgical Quarterly》1996,18(3):185-199
This paper discusses several data analytic technique, for examining treatment efficacy in pretest-posttest control group designs. The following approaches are described: ANOVA on post scores, ANOVA on difference scores, split-plot repeated measures ANOVA, profile analysis, and ANOCOVA with prescore as the co-variate. Guidelines for choosing between available techniques are provided; the primary focus here is on the nature of the null hypothesis, the assumptions underlying the approach, and the power of the procedure. The importance of examining the characteristics of the data set in selecting an analytic technique is illustrated. 相似文献
96.
Carbonaceous spherules of mesophase were examined by transmission electron microscopy (TEM) and X-ray diffraction to precisely
clarify its structure. A series of thin sections were cut from a single spherule with a microtome, and the three-dimensional
lamellar structure of the spherule investigated. From 002 dark-field images and selected area electron diffractions (SAD),
it was observed that the spherule was of the Brooks-Taylor type, with the lamellae being parallel even at the poles of the
spherule. Structural changes within the spherule was studied following carbonization and graphitization. The structure of
the resultant coke was essentially that of spherule of mesophase. Size of the lamellae increased as well as. The number of
stacking lamellae also increased, but a rapid increase was not seen. The spherules of mesophase show a high degree of homogeneity
and an excellent degree of graphitization. 相似文献
97.
The programmed diffusional release rate of an active agent through a rate-controlling membrane from a cosolvent system is discussed. At initial conditions, the drug is present below saturation in solution in a solvent mixture, enclosed by the rate-controlling membrane; the solvent is composed of the main solvent and a consolvent, which increases the drug solubility in the main solvent. During operation, the active agent and cosolvent diffuse from the capsule at a rate controlled by the membrane. Equations were derived describing the release rate of the active agent as a function of the permeability of the cosolvent and agent, the capsule dimensions, and the system's initial conditions. A great variety of release rate profiles can be programmed from declining to increasing delivery rate patterns as a function of time. Experimental data are presented for the drug progesterone in solution in cyclohexane with methyl, heptyl, or cetyl alcohol as the cosolvent in a polyethylene capsule. The theory qualitatively predicts the theory qualitatively predicts the experimental results. 相似文献
98.
An analysis of the theoretical behavior of a proposed zero-order drug delivery system is presented. Equations describing drug release with time are developed using a physically realistic model. The theory agrees well with experimental data and indicates that drug release from the device is nearly, although not rigorously, zero order. 相似文献
99.
Extraction of a plasma time-activity curve from dynamic brain PET images based on independent component analysis 总被引:1,自引:0,他引:1
Naganawa M Kimura Y Ishii K Oda K Ishiwata K Matani A 《IEEE transactions on bio-medical engineering》2005,52(2):201-210
A compartment model has been used for kinetic analysis of dynamic positron emission tomography (PET) data [e.g., 2-deoxy-2-18F-fluoro-D-glucose (FDG)]. The input function of the model [the plasma time-activity curve (pTAC)] was obtained by serial arterial blood sampling. It is of clinical interest to develop a method for PET studies that estimates the pTAC without needing serial arterial blood sampling. For this purpose, we propose a new method to extract the pTAC from the dynamic brain PET images using a modified independent component analysis [extraction of the pTAC using independent component analysis (EPICA). Source codes of EPICA are freely available at http://www5f.biglobe.ne.jp/?kimura/Software/top.html]. EPICA performs the appropriate preprocessing and independent component analysis (ICA) using an objective function that takes the various properties of the pTAC into account. After validation of EPICA by computer simulation, EPICA was applied to human brain FDG-PET studies. The results imply that the EPICA-estimated pTAC was similar to the actual measured pTAC, and that the estimated blood volume image was highly correlated with the blood volume image measured using 15O-CO inhalation. These results demonstrated that EPICA is useful for extracting the pTAC from dynamic PET images without the necessity of serial arterial blood sampling. 相似文献
100.