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排序方式: 共有478条查询结果,搜索用时 15 毫秒
41.
HM El-Zimaity H Ota S Scott DE Killen DY Graham 《Canadian Metallurgical Quarterly》1998,122(8):732-736
OBJECTIVE: To develop an inexpensive stain to simultaneously visualize gastric morphology and Helicobacter pylori. METHODS: Gastric biopsies were stained with Genta stain using manual methods, and with carbol fuchsin/Alcian blue/hematoxylin-eosin using an automatic slide stainer (Sakura DRS-601). Slides were then coded and interpreted by 2 pathologists. Helicobacter pylori was scored using a visual scale (0 [none] to 5 [maximum]). RESULTS: One hundred slides were scored; H pylori was present in 64%. Carbol fuchsin/Alcian blue/hematoxylin-eosin stain gave excellent demonstration of gastric morphology. All positive cases (score > or =2) were correctly interpreted. Thirty-six slides had a score of 1 (< or =2 bacteria per entire slide). Of these, 10 were scored negative by Genta stain and 12 were scored negative by the carbol fuchsin/Alcian blue/hematoxylin-eosin stain (P = not significant). Hematoxylin-eosin was significantly less accurate than either of the other 2 stains (P < .02). CONCLUSION: The carbol fuchsin/Alcian blue/hematoxylin-eosin (El-Zimaity) stain is an economical stain suitable for simultaneous visualization of H pylori infection and gastric morphology. 相似文献
42.
Holmes Clarissa S.; Dunlap William P.; Chen Ru San; Cornwell John M. 《Canadian Metallurgical Quarterly》1992,60(5):698
Evaluated the learning status of 95 diabetic boys and girls and 97 matched controls using the Wechsler Adult Intelligence Scale—Revised (WAIS—R) IQ factors and school histories. Of interest was whether diabetic boys would evidence more learning difficulties. Results indicated that diabetic boys had significantly lower Freedom From Distractibility scores compared with the scores of diabetic girls and control Ss and lower Perceptual Organization scores compared with scores of control boys. Although group scores were still within the average range of functioning, a significantly high percentage of diabetic boys (40%) compared with diabetic girls (16%) had learning problems that warranted either special instructional services or grade retention. Diabetic children experienced more learning difficulties (24%) than controls (13%), supporting research findings that diabetes is associated with increased risk of learning problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
T Sakai MK Razavi CP Semba ST Kee DY Sze MD Dake 《Canadian Metallurgical Quarterly》1998,9(6):1025-1028
Lactic acidosis due to thiamine deficiency is known to complicate chemotherapy and radiotherapy treatment of malignant extracranial tumors, but to the authors' knowledge, this complication has not been reported in patients treated for malignant brain tumors. They report three such cases, demonstrating that this complication can occur during treatment of brain tumors. In all patients, consciousness levels deteriorated within 1 to 2 days. Serum lactic acid levels increased to concentrations between 62 and 96.7 mg/dl, resulting in severe metabolic acidosis. A low blood thiamine level (9 ng/ml) was demonstrated at the onset in one case, and high-dose thiamine infusions dramatically improved lactic acidemia as well as impairment of consciousness in two cases. In the other case, hydrocephalus was suspected initially, resulting in a delay in thiamine supplementation. Clinical differentiation of this form of lactic acidosis from hydrocephalus or tumor progression can be very difficult in a patient undergoing treatment for a malignant brain tumor. Demand for thiamine is thought to be increased in patients with malignant brain tumors, and supplemental thiamine during treatment is necessary to prevent lactic acidosis. When this complication occurs, immediate treatment with sufficient thiamine is essential, together with normalization of pH by using sodium bicarbonate. With timely intervention, the level of consciousness can recover to the preacidotic state with no new neurological deficits. 相似文献
44.
Chow D.H. Dunlap H.L. Williamson W. III Enquist S. Gilbert B.K. Subramaniam S. Lei P.-M. Bernstein G.H. 《Electron Device Letters, IEEE》1996,17(2):69-71
Integrated resonant interband tunneling (RIT) and Schottky diode structures, based on the InAs/GaSb/AlSb heterostructure system, are demonstrated for the first time. The RIT diodes are advantageous for logic circuits due to the relatively low bias voltages (~100 mV) required to attain peak current densities in the mid-104 A/cm 2 range. The use of n-type InAs/AlSb superlattices for the semiconducting side of Schottky barrier devices provides a means for tailoring the barrier height for a given circuit architecture. The monolithically integrated RIT/Schottky structure is suitable for fabrication of a complete diode logic family (AND, OR, XOR, INV) 相似文献
45.
M Dominguez K Dejgaard J Füllekrug S Dahan A Fazel JP Paccaud DY Thomas JJ Bergeron T Nilsson 《Canadian Metallurgical Quarterly》1998,140(4):751-765
Abstract. Five mammalian members of the gp25L/ emp24/p24 family have been identified as major constituents of the cis-Golgi network of rat liver and HeLa cells. Two of these were also found in membranes of higher density (corresponding to the ER), and this correlated with their ability to bind COP I in vitro. This binding was mediated by a K(X)KXX-like retrieval motif present in the cytoplasmic domain of these two members. A second motif, double phenylalanine (FF), present in the cytoplasmic domain of all five members, was shown to participate in the binding of Sec23 (COP II). This motif is part of a larger one, similar to the F/YXXXXF/Y strong endocytosis and putative AP2 binding motif. In vivo mutational analysis confirmed the roles of both motifs so that when COP I binding was expected to be impaired, cell surface expression was observed, whereas mutation of the Sec23 binding motif resulted in a redistribution to the ER. Surprisingly, upon expression of mutated members, steady-state distribution of unmutated ones shifted as well, presumably as a consequence of their observed oligomeric properties. 相似文献
46.
A Jacobs B Jones C Ricketts RD Bulbrook DY Wang 《Canadian Metallurgical Quarterly》1976,34(3):286-290
A simplification of Kiresuk's and Sherman's approach to the measurement of therapeutic success is proposed. Hypothetical cases are given as examples. 相似文献
47.
Absolute and relative quantities of elastin, collagen, and DNA in anatomically defined segments of rabbit ascending aorta (AA) and pulmonary trunk (PT) were compared at intervals from birth to 2 months of age. Identical in size, weight, and composition at birth, the vessels maintained similar lengths and diameters at each age but diverged markedly in weight and scleroprotein content after 1 week. By 2 months, 3 times as much elastin and 1.7 times as much collagen had accumulated in the AA as compared to the PT. By contrast, the increase in total DNA content was the same for both segments. Differences in total fibrous protein accumulation, total elastin accumulation, and elastin content relative to DNA paralleled differences in estimated total medial tangential tension. Proportions of elastin and collagen relative to dry weight increased markedly only between 4 and 2 weeks of age and not thereafter despite continuing rapid growth, steadily increasing medial tension, and increasing total scleroprotein content. Thus, medial cells were capable of adapting their quantitative scleroprotein synthetic response to differences in medial tension throughout growth but established a fixed qualitative response within 2 weeks. 相似文献
48.
John R. Kennedy John R. Dunlap Rod D. Bunn David F. Edwards 《Microscopy research and technique》1988,8(2):159-172
Tracheal ciliary cross sections were examined with scanning transmission electron microscopy and the resultant images were digitized for image enhancement. A gray-scale histogram of each ciliary image was produced and manipulated to enhance the image for dynein arms. Tracheal epithelial tissue from the pig, rabbit, and dog, including dogs with immotile cilia syndrome, was examined by using this technique. Tissue from each animal was fixed with each of three different fixatives and sections were evaluated for preservation of dynein arms. The same fixative did not consistently provide optimal fixation for ciliary dynein arms in all three species examined. Each species, therefore, must be evaluated to determine the optimal fixative for preservation of normal ciliary ultrastructure. Digital image processing provides a mechanism for enhancing dynein arms in situ without the need for addition of special stains or the use of techniques such as image summation. With this technique it has been shown that about two-thirds of outer dynein arms are partially or completely missing on cilia from dogs with immotile cilia syndrome. 相似文献
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