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991.
A newly developed holder for a right-angled metal venous cannula was developed to make direct insertion into each cava easier, especially insertion into the superior vena cava in pediatric open heart operations. We have been using this holder with ease and safety in all cases of small babies.  相似文献   
992.
An easy technique has been developed to fabricate optically transparent lanthanum-modified lead zirconate titanate (PLZT) ceramics. This technique consists of three stages: (1) sintering in an oxygen atmosphere, (2) elimination of pores in a carbon dioxide atmosphere, and (3) elimination of oxygen vacancies in an oxygen atmosphere. The carbon dioxide atmosphere enhances the diffusion of oxygen from the pores to outside the sintered body. The experimental results reveal that use of a carbon dioxide atmosphere effectively decreases residual pores and improves optical transmittance. From commercially available raw powders, an optical transmittance of 51% (wavelength of 550 nm) can be achieved for 0.7 mm thick polished PLZT9/65/35 ceramics using a carbon dioxide atmosphere, whereas the value is only 34% without a carbon dioxide atmosphere. The advantage of this technique is that PLZT ceramics having high optical quality can be obtained using conventional sintering tools.  相似文献   
993.
A 50-year-old man with Churg-Strauss syndrome showed granulocytes (GNLs) which generated more superoxide anion (O2-) than GNLs from healthy subjects following in vitro stimulation with C5a or C3a. Production of O2- subsided as the clinical symptoms improved with steroid treatment. A hyperresponsiveness of GNLs may be involved in this disorder.  相似文献   
994.
Up to now, the diagnosis of H. pylori infection has been made by the breath test using 13C-urea. In this study, 13C-urea breath samples were tested in 34 patients (peptic ulcer scar 17, chronic gastritis 17 cases) with an automated breath 13C analyzer (ABCA. Europa Scientific, Crewe, UK) and compared with the results of endoscopical diagnosis for H. pylori infection. Endoscopic and 13C-urea breath test (13C-UBT) were performed before eradicative medication. We described a modified protocol for the growth grade of H. pylori colonies in microbiology (H. pylori score), and for the delta 13C area under curve (AUC; permil*hr) obtained from each sample of expired breath. There was a significant correlation between delta 13C-AUC and the delta 13C level of each sample, but the correlation coefficient obtained at 10min (R2 = 0.582) was lower than that obtained at the other four time points (20min; 0.891, 30min; 0.949, 40min; 0.946, 50min; 0.946, 60min; 0.820). The delta 13C-AUC well correlated with H. pylori score (p < 0.01), none of 26 H. pylori positive patients detected by culture was 13C-UBT negative (delta 13C-AUC < 8.2 permil*hr in mean + 2SD of H. pylori negative group). In conclusion, 13C-UBT using ABCA has high sensitivity and specificity, and it provides a non-invasive method for the detection of H. pylori urease activity.  相似文献   
995.
We have measured drift velocities and Lorentz angles for xenon gas with various types of quench gas mixtures. The measurement was motivated to help designing a new type of detector for an e+e collider experiment, where synchrotron radiation X-rays generated by electrons passing through a high magnetic field are detected to identify the electrons.  相似文献   
996.
Attempted to quantify the clinical work of S. Ferenczi. Data from 116 psychoanalysts who rated one of Ferenczi's clinical cases suggest a positive view of Ferenczi's work. His therapeutic process was viewed as emotional-experiential and less likely to be rated as an intellectual-cognitive process. Although Ss thought Ferenczi was a skillful therapist, they did not want this therapist as their analyst or supervisor and felt they would do things differently if they were the therapist. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
New signal readout method for ultrahigh-sensitivity CMOS image sensor   总被引:2,自引:0,他引:2  
We propose a new signal readout method that uses a charge-transfer circuit. Its application is to an ultrahigh-sensitivity CMOS image sensor on which an avalanche-mode photoconductive film is overlaid. The charge-transfer circuit makes it possible to obtain high signal-to-noise ratio features by transferring signal charges accumulated in each photodiode to a parasitic capacitance that is small compared with the photodiode capacitance. A 138 /spl times/ 138 passive-pixel prototype sensor that had the charge-transfer circuit in each column was fabricated and tested. The prototype's column-to-column fixed-pattern noise and random noise were, respectively, 56.7 and 58.4 dB below the saturation signal level, which demonstrated its potential as a signal readout circuit for a next-generation ultrahigh-sensitivity CMOS image sensor.  相似文献   
998.
A learning controller is presented for a Markovian decision problem in which the transition probabilities are unknown. This controller, which is designed to be asymptotically optimal with consideration of a conflict between estimation and control, uses a performance criterion incorporating a tradeoff between them explicitly for determination of a control policy. It is shown that this controller achieves asymptotic optimality in the sense that the relative frequency of applying the optimal policy converges to unity.  相似文献   
999.
Disulfide bond structure of human epidermal growth factor receptor   总被引:1,自引:0,他引:1  
The extracellular domain of the human epidermal growth factor receptor (sEGFR) consists of 621 amino acid residues, including 50 cysteines. The connections of the 25 disulfide bonds in the recombinant sEGFR protein, obtained from Chinese hamster ovary cells, have been determined using N-terminal sequencing and matrix-assisted laser desorption/ionization mass spectroscopy. We identified a basic repeat of eight cysteines with a 1-3, 2-4, 5-6, and 7-8 disulfide pairing pattern in the two cysteine-rich regions of sEGFR. By comparison to other cysteine-rich motifs, it was concluded that the cysteine-rich repeat of sEGFR belongs to the laminin-type EGR-like (LE) structural motif. Three-dimensional structure models of the two cysteine-rich regions have been built, based on the three-dimensional structures of the LE domains from the laminin gamma1 chain and secondary structure predictions for the EGF receptor.  相似文献   
1000.
Recent studies have suggested the existence of one or several tumor-suppressor genes on chromosome arm 1p in colorectal tumors. To determine the localization of the putative tumor suppressor genes, we performed LOH analysis in 1p in colorectal tumors. A total of 48 paired normal and tumor DNAs of 46 colorectal tumor patients and 21 microsatellite markers on 1p32.1-p36.3 were used for PCR-LOH analysis. Three commonly deleted regions were found: i) 1p36.3 (10-cm); ii) 1p35.1-p36.3 (2-cm); and iii) 1p34.2-p35 (1-cm). These regions overlapped with those reported in several types of tumor. No significant associations were found between LOH and clinicopathologic features. The regions identified in the present study could harbor tumor suppressor genes that would also be associated with several types of human cancer.  相似文献   
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