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31.
S Kawaguchi S Ishimaru N Koizumi T Shimazaki Y Obitsu M Ishikawa 《Canadian Metallurgical Quarterly》1998,46(10):1047-1051
OBJECTIVE: To determine the pharmacokinetics and absolute bioavailability of ciprofloxacin in 12 critically ill patients receiving continuous enteral feeding. Design: a prospective, cross-over study. SETTING: 12-bed surgical intensive care unit in a University Hospital. PATIENTS: 12 stable critically ill patients on mechanical ventilation and receiving continuous enteral feeding (Normoreal fibres) without diarrhea or excessive residual gastric contents ( < 200 ml/4 h). None had gastro-intestinal disease, renal insufficiency (estimated creatinine clearance > or = 50 ml/min) or was receiving medications that could interfere with ciprofloxacin absorption or metabolism. MEASUREMENTS AND MAIN RESULTS: The study was carried out after the fourth (steady state) b. i. d. intravenous (i. v.) 1-h infusion of 400 mg and the second b. i. d. nasogastric (NG) dose of 750 mg (crushed tablet in suspension). Plasma concentrations were measured by high-performance liquid chromatography. The median (range) peak concentration after i. v. infusion was 4.1 (1.5-7.4) mg/l, and that after NG administration was 2.3 (0.7-5.8) mg/l, occurring 1.25 (0.75-3.33) h after dosing. The median [range] areas under plasma concentration-time curves were similar for the two administration routes (10.3 [3.3-34.6] and 8.4 [3.6-53.4] for i.v. infusion and NG administration, respectively). Ciprofloxacin bioavailability ranges from 31 to 82 % (median, 44%). CONCLUSIONS: In tube-fed critically ill patients, a switch to the NG ciprofloxacin after initial i. v. therapy to simplify the treatment of severe infections is restricted to those for whom serial assessments of ciprofloxacin levels are routinely available. 相似文献
32.
This paper proposes a novel human-robot symbiosis system named a Robotic Office Room (ROR). The understanding, recording and retrieving of telephone call behavior are successfully demonstrated as a typical example of an office work-supporting function of ROR. A unique object model is proposed, which accumulates information concerning motion of the object. This model enables the system to understand human behavior, not by monitoring the motion of the human, but by monitoring the motion of the object-typically, a telephone or pen. Since the model requires the system to pay spatial and temporal attention only to the target object and related motions, it saves computing power. Repertoires of understandable behavior can easily be expanded by simply adding new object models. The ROR is equipped with networked machines. The concept of "ubiquitous link" consisting of unique image channels and remote control channels is proposed. The image channel and the remote control channel utilize TV images and either ultrasonic waves or infrared rays, respectively. Such cooperative support of humans by networked machines is realized that when a human starts to talk on the phone, the ROR not only starts to record the image of the human's behavior, utilizing a VCR, but also turns down the volume on an audio set. The experiment proved the feasibility of the ROR as an integrated robotic system to support human office work. 相似文献
33.
Tadashi Kusumoto Osamu Ishikawa Takao Mizusaki Akira Hirai 《Journal of Low Temperature Physics》1985,59(3-4):269-289
The nuclear spin dynamics in nuclear spin ordered solid3He in low magnetic fields on the melting curve has been studied by pulsed NMR down to 0.6 mK. The free induction decay signals (FID) were measured in single crystals of solid3He at three operating frequencies of 920, 1380, and 1840 kHz. The FIDs were nonexponential and dependent on the rf pulse strength
p
H
1
t
w
, where is the gyromagnetic ratio,H
1 is the rf field strength, andt
w
is the pulse width. At small
p
they decayed almost linearly in time with a small exponential tail at the end. When
p
was further increased they became shorter and neither exponential nor linear in time. At large
p
they decayed very rapidly and sometimes could not be observed at all because of the dead time of the NMR detection system. Such behavior of the FID was observed in many different single crystals in the given temperature range at 920 kHz. Tsubota and Tsuneto have shown by solving the nonlinear equations of motion numerically that the motion of the nuclear spin becomes chaotic when the tipping angle exceeds a critical value. Comparing their result with our experimental results, we concluded that some of the results of the rapid decay of the FID at large
p
might be attributed to the onset of the chaotic motion. At 1840 kHz it is expected that the nonlinear effects in the equations of motion become less effective than that at 920 kHz. In fact, at this operating frequency the FIDs even at large
p
and the tipping angle-dependent frequency shift could be observed. These frequency shifts were in rather good agreement with Namaizawa's theory provided an effective tipping angle was taken into account. 相似文献
34.
Masashi Ishikawa Masae Iwasaki Hailin Zhao Junichi Saito Cong Hu Qizhe Sun Atsuhiro Sakamoto Daqing Ma 《International journal of molecular sciences》2021,22(9)
Inhalational anesthetics was previously reported to suppress glioma cell malignancy but underlying mechanisms remain unclear. The present study aims to investigate the effects of sevoflurane and desflurane on glioma cell malignancy changes via microRNA (miRNA) modulation. The cultured H4 cells were exposed to 3.6% sevoflurane or 10.3% desflurane for 2 h. The miR-138, -210 and -335 expression were determined with qRT-PCR. Cell proliferation and migration were assessed with wound healing assay, Ki67 staining and cell count kit 8 (CCK8) assay with/without miR-138/-210/-335 inhibitor transfections. The miRNA downstream proteins, hypoxia inducible factor-1α (HIF-1α) and matrix metalloproteinase 9 (MMP9), were also determined with immunofluorescent staining. Sevoflurane and desflurane exposure to glioma cells inhibited their proliferation and migration. Sevoflurane exposure increased miR-210 expression whereas desflurane exposure upregulated both miR-138 and miR-335 expressions. The administration of inhibitor of miR-138, -210 or -335 inhibited the suppressing effects of sevoflurane or desflurane on cell proliferation and migration, in line with the HIF-1α and MMP9 expression changes. These data indicated that inhalational anesthetics, sevoflurane and desflurane, inhibited glioma cell malignancy via miRNAs upregulation and their downstream effectors, HIF-1α and MMP9, downregulation. The implication of the current study warrants further study. 相似文献
35.
Knowledge based approach is effective for renovating design and manufacturing processes. The objective of this paper is to investigate roles and usages of expert engineering knowledge in high-quality manufacturing, and to study a practical knowledge capturing method for realizing engineering support tools. An engineer oriented interface for a capturing method is proposed, and a flexible representation framework is studied for various types of expert knowledge. An integrated knowledge-based system has been developed for mold design support. The results have been evaluated by design and manufacturing of molds for cellular phones, and have shown substantial reduction of lead time for mold production. 相似文献
36.
The rates of absorption of oxygen into aqueous cuprous chloride solutions containing hydrochloric acid were measured at 15, 25 and 35°C using a baffled agitated vessel operated batchwise and the experimental results were analyzed with the chemical absorption theory. The reaction between oxygen and cuprous chloride was found to be second order, i.e. first order with respect to oxygen and CuCl2? ion which is the actual reactive species in aqueous cuprous chloride solutions containing hydrochloric acid. The reaction rate constants were calculated and correlated as a function of temperature. 相似文献
37.
This paper presents a dynamic compensation concept to grapple with the dynamic defects of a traditional robot arm, especially while performing high-speed endpoint regulations. The proposed high-speed dynamic compensation concept offers a new point of view for cooperating with a traditional manipulator to realize highly dexterous performance of manipulations. The concept is realized through adoption of a high-speed light-weight actuator as well as endpoint closed loop configured high-speed cameras. The dynamic compensation is analyzed experimentally with 1000 Hz visual feedback and a high-speed finger for a robot arm in the case of one degree of freedom. The advantage of the proposed approach is that the modeling for the robot system’s dynamics is not needed, whereas it is necessary and trivial in order to realize high-speed regulations by traditional approaches. Thus, the control issue becomes easier with the proposed approach. As an application for this concept, fast peg-and-hole alignment with large position and attitude uncertainty is studied. The alignment algorithm is based on a visual compliance strategy. Alignment experiments show that with the proposed concept of dynamic compensation as well as visual compliant motion control, robust and fast convergence was realized for most cases. 相似文献
38.
A new and effective liquid membrane process to achieve both separation and enrichment simultaneously of weak organic acids or bases was developed. The process utilizes effectively the difference in the apparent partition coefficient of the constituent species between the aqueous and organic phases, and uses the change of the apparent partition coefficients with the hydrogen ion concentration of the aqueous phase. For such a fundamental model apparatus as a diaphragm diffusion cell being operated batch wise, the effects of pK value of solutes, permeability of solutes through the membrane, volume ratio of liquids in two aqueous phases, and pH value of aqueous phase on enrichment factor and selectivity for the solute to be concentrated were discussed analytically. Separation and enrichment were demonstrated using aqueous mixed solutions of fumaric acid and L-malic acid. The results were in good agreement with the theoretical predictions. 相似文献
39.
The strength, S , of ceramic and glass fibers often can be estimated from fractographic investigation using the fracture mirror radius, r m , and the relationship S = A m /( r m )1/2 , where A m is the "mirror constant." The present work estimates the value of A m for Tyranno® Si-Ti-C-O fibers in situ in a three-dimensional woven SiC/SiC-based composite to be 2.50 ± 0.09 MPa·m1/2 . This value is within the range of 2–2.51 MPa·m1/2 previously obtained for nominally similar Nicalon® Si-C-O fibers. 相似文献
40.
Arai Kazuhito; Hishida Atsushi; Ishiyama Mariko; Kamata Takeo; Uchikoba Hiroyuki; Fushinobu Shinya; Matsuzawa Hiroshi; Taguchi Hayao 《Protein engineering, design & selection : PEDS》2002,15(1):35-41
Lactobacillus casei allosteric L-lactate dehydrogenase (L-LDH)absolutely requires fructose 1,6-bisphosphate [Fru(1,6)P2] forits catalytic activity under neutral conditions, but exhibitsmarked catalytic activity in the absence of Fru(1,6)P2 underacidic conditions through the homotropic activation effect ofsubstrate pyruvate. In this enzyme, a single amino acid replacement,i.e. that of His205 conserved in the Fru(1,6)P2-binding siteof certain allosteric L-LDHs of lactic acid bacteria with Thr,did not induce a marked loss of the activation effect of Fru(1,6)P2or divalent metal ions, which are potent activators that improvethe activation function of Fru(1,6)P2 under neutral conditions.However, this replacement induced a great loss of the Fru(1,6)P2-independentactivation effect of pyruvate or pyruvate analogs under acidicconditions, consequently indicating an absolute Fru(1,6)P2 requirementfor the enzyme activity. The replacement also induced a significantreduction in the pH-dependent sensitivity of the enzyme to Fru(1,6)P2,through a slight decrease and increase of the Fru(1,6)P2 sensitivityunder acidic and neutral conditions, respectively, indicatingthat His205 is also largely involved in the pH-dependent sensitivityof L.casei L-LDH to Fru(1,6)P2. The role of His205 in the allostericregulation of the enzyme is discussed on the basis of the knowncrystal structures of L-LDHs. 相似文献