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111.
一款优秀的科技产品或一项优秀服务的成功除了需要先进的技术和理念外,一个好听易记的名字也必不可少。在此,我们选取了iPod等四大殿堂级科技产品,探究其起名的缘由。 相似文献
112.
Psychotherapy studies published in the Journal of Counseling Psychology (JCP) and the Journal of Consulting and Clinical Psychology (JCCP) between 1978 and 1992 were examined. Differences were found between the 2 journals. JCP published mostly process, outcome, and analog research, whereas JCCP published mostly outcome research. Most process and process-outcome studies across journals were of individual, brief therapy. Across the years, more diversity was evident in samples used in process research in terms of student status, gender, and race of clients and therapists. Three content areas were prominent in the process measures and classic studies: therapist techniques, therapist influence, and facilitative conditions. Lists are provided of the frequently used measures, most productive authors, and classic studies in process research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
RG Ciocca DK Wilkerson DL Madson CT Andrew AM Graham 《Canadian Metallurgical Quarterly》1995,9(2):204-208
Congenital abnormalities of the aortic arch may lead to signs and symptoms of tracheal and esophageal obstruction secondary to a restrictive vascular ring. There are many case reports and monographs concerning the surgical management of dysphagia lusoria. This case provides the first example of long-term follow-up of surgical intervention for relief of dysphagia lusoria. A 45-year-old laborer presented with a several year history of episodic bilateral blindness and a more recent onset of "drop attacks." Notably this patient had presented at the age of 18 months with difficulty breathing and eating since birth. The patient also had frequent upper respiratory infections and episodes of pneumonia. Workup revealed a right-sided aortic arch with a left ligamentum arteriosum. When he was first seen in our clinic, history and physical examination revealed claudication and diminished pulses in the left upper extremity. Arteriography and duplex studies confirmed reversal of flow in the patient's left vertebral artery. The arteriogram demonstrated the presence of a right-sided aortic arch and descending aorta along with the proximal stump of the previously ligated left subclavian artery. He underwent left carotid to left axillary artery bypass for the treatment of symptomatic subclavian steal syndrome. His symptoms have resolved with return of antegrade vertebral flow and the presence of normal pulses in the left arm. Congenital aortic abnormalities that lead to tracheal and esophageal compromise are numerous and varied. Surgical management requires a thorough understanding of the person's anatomy and preoperative planning. The life expectancy of patients with dysphagia lusoria necessitates consideration of the long-term consequences of surgical intervention. 相似文献
114.
115.
It is known that marine sediments can support both compressional and shear waves. However, published work on scattering from irregular elastic media has not examined the influence of shear on sea bed scattering in detail. A perturbation model previously developed by the authors for joint roughness-volume scattering is used to study the effects of elasticity for three sea bed types: sedimentary rock, sand with high shear speed, and sand with "normal" shear wave speed. Both bistatic and monostatic cases are considered. For sedimentary rock it is found that shear elasticity tends to increase the importance of volume scattering and decrease the importance of roughness scattering relative to the fluid case. Shear effects are shown to be small for sands. 相似文献
116.
MR Harrison GB Mychaliska CT Albanese RW Jennings JA Farrell S Hawgood P Sandberg AH Levine E Lobo RA Filly 《Canadian Metallurgical Quarterly》1998,33(7):1017-22; discussion 1022-3
BACKGROUND/PURPOSE: Fetuses with congenital diaphragmatic hernia (CDH) who have a "poor prognosis" with postnatal treatment now can be identified on the basis of liver herniation, early diagnosis (before 25 weeks' gestation) and a low lung-to-head ratio (LHR). Because complete in utero repair proved unsuccessful for this group, the strategy of temporary tracheal occlusion was developed to gradually enlarge the hypoplastic fetal lung. The purpose of this study is to compare the outcome of patients in the poor-prognosis group treated by one of three methods: (1) standard postnatal care, (2) fetal tracheal occlusion via open hysterotomy, and (3) the recently developed video-fetoscopic (Fetendo) technique of tracheal occlusion without hysterotomy. METHODS: In the past 3 years, 34 of 86 fetuses with an isolated left CDH met criteria for the poor-prognosis group. Thirteen families chose postnatal treatment at an extracorporeal membrane oxygenation (ECMO) center, 13 underwent open fetal tracheal occlusion, and eight underwent fetoscopic tracheal occlusion. RESULTS: The survival rate was 38% in the group treated by standard postnatal therapy, 15% in the open tracheal occlusion group, and 75% in the Fetendo group. There were less postoperative pulmonary complications noted in mothers who underwent the Fetendo procedure versus the open tracheal occlusion. All but one Fetendo clip patient had a striking physiological response demonstrated by sonographic enlargement of the small left lung that was documented postnatally by plain radiographs and its subjective appearance during repair of the CDH. In contrast, only 5 of the 13 open tracheal occlusion patients demonstrated lung growth. CONCLUSION: Fetuses with a left CDH who have liver herniation and a low LHR are at high risk of neonatal demise and appear to benefit from temporary tracheal occlusion when performed fetoscopically, but not when performed by open fetal surgery. 相似文献
117.
AM Jackson AV Ivshina O Senko A Kuznetsova A Sundan MA O'Donnell S Clinton AB Alexandroff PJ Selby K James VA Kuznetsov 《Canadian Metallurgical Quarterly》1998,159(3):1054-1063
PURPOSE: The goal of this research was to discover new biological indicators in urine which could be used for short-term prognosis of local Bacillus Calmette-Guerin (BCG) therapy outcome in patients with superficial bladder cancer. PATIENTS AND METHODS: We measured and statistically evaluated soluble immunological molecules in urine from bladder cancer patients (n = 34) receiving BCG intravesically. Urine was collected following each of 6 weekly treatments, processed and assayed. The data base included measurements of interleukin-1 (IL-2, IL-4, IL-6, IL-10, IL-12, soluble intercellular adhesion molecule-1 (sICAM-1), tumour necrosis factor-alpha (TNF alpha), soluble CD14 (sCD14), interferon-gamma (IFN gamma), GM-CSF, volume of urine and its pH. The clinical response was evaluated by urine histology and random quadrant biopsy 3 months after the start of therapy. Patients were divided into 2 groups, with good and poor therapeutic effect. The initial complete response rate was 62% (21/34). The data base was analyzed using traditional multivariate statistical methods and a pattern recognition method which deals with combinatorial-statistical analysis (statistically weighted syndromes (SWS) method) of the gradated features. The SWS method is capable of identifying robust patterns in small "fuzzy" sets with high dimensional objects and some missing values. RESULTS: Only one parameter gave significant differences at p < 0.05, GM-CSF at instillation 6. Repeated measurement analysis of variance, backward stepwise multiple logistic regression and linear discriminant analysis failed to show any significance. However, significant differences in the structure of correlation between features in the groups with and without therapeutic effect were observed and four highly informative variables (the masses of sICAM-1, TNF alpha, sCD14 and pH) relating to 5th-6th installations were selected by SWS. These features provided accurate individual prediction of therapeutic outcome for all our patients. Cross-validation analysis and computer simulation showed the statistically significant stability of the prediction. CONCLUSION: We have selected a set of urinary variables that could be considered as a perspective combination of indicators (syndromes) of outcome of pre-operation BCG therapy of patients with superficial bladder cancer. A larger patient database will provide testing and evaluation of the biological and clinical significance of selected features. The computational syndrome-disease approach should be applicable for the solution of decision-making problems for management of cancer. 相似文献
118.
CT Dolphin DJ Beckett A Janmohamed TE Cullingford RL Smith EA Shephard IR Phillips 《Canadian Metallurgical Quarterly》1998,273(46):30599-30607
Flavin-containing monooxygenases (FMOs) are NADPH-dependent flavoenzymes that catalyze the oxidation of heteroatom centers in numerous drugs and xenobiotics. FMO2, or "pulmonary" FMO, one of five forms of the enzyme identified in mammals, is expressed predominantly in lung and differs from other FMOs in that it can catalyze the N-oxidation of certain primary alkylamines. We describe here the isolation and characterization of cDNAs for human FMO2. Analysis of the sequence of the cDNAs and of a section of the corresponding gene revealed that the major FMO2 allele of humans encodes a polypeptide that, compared with the orthologous protein of other mammals, lacks 64 amino acid residues from its C terminus. Heterologous expression of the cDNA revealed that the truncated polypeptide was catalytically inactive. The nonsense mutation that gave rise to the truncated polypeptide, a C --> T transition in codon 472, is not present in the FMO2 gene of closely related primates, including gorilla and chimpanzee, and must therefore have arisen in the human lineage after the divergence of the Homo and Pan clades. Possible mechanisms for the fixation of the mutation in the human population and the potential significance of the loss of functional FMO2 in humans are discussed. 相似文献
119.
beta-N-Acetylhexosaminidase was purified from the extract of cabbage by sequential steps of ammonium sulfate fractionation, chromatofocusing, DEAE-Sepharose CL-6B ion exchange chromatography and Sephacryl S-200 HR gel filtration. By these steps, the purity of the enzyme increased by 256 fold with a recovery of 8%. The purified enzyme was homogeneous as examined by native PAGE. It showed an optimal pH of 4, an optimal temperature of 60 degrees C and a Km of 0.94 mM for hydrolysis of pNp-beta-GlcNAc. The molecular mass of the enzyme determined from filtration through Sephacryl S-200 was 150 kDa. Three subunits with molecular mass of 64, 57 and 51 kDa were observed as determined by SDS-PAGE. NBS (0.025 mM), DEPC (3 mM) and WRK (30 mM) significantly inhibited the activity of the enzyme. The enzyme also showed activity toward pNp-beta-GalNAc, N,N'-diacetylchitobiose, N,N',N"-triacetylchitotriose and N,N',N",N"'-tetraacetyl chitotetraose but showed no activity toward pNp-alpha-GlcNAc, chitin and ethylene glycol chitin. 相似文献
120.
We describe a simple visible-light stray-background-reducing baffle, suitable for use on a stabilized interplanetary platform. The design is a corrallike enclosure with five concentric walls. The baffle reduces direct sunlight and reflections from illuminated portions of the spacecraft by a factor of 10(-12), provided that all these lie beyond at least a hemisphere centered on the viewing aperture. With this condition these bright sources do not directly illuminate within the outermost wall of the corral, and diffraction over the wall tops is the dominant mechanism by which light reaches the corral interior. We present design calculations for such a corral, as well as a laboratory measurement confirming the basic design assumption. 相似文献