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101.
D Averill D Blockus B Brabson J Brom C Jung H Ogren DR Rust M Derrick P Kooijman JS Loos B Musgrave LE Price J Repond K Sugano B Cork C Akerlof J Chapman D Errede MT Ken DI Meyer H Neal D Nitz R Thun R Tschirhart S Abachi P Baringer BG Bylsma R DeBonte D Koltick EH Low RL McIlwain DH Miller CR Ng EI Shibata 《Canadian Metallurgical Quarterly》1989,39(1):123-137
102.
DH Kang CL Coe DO McCarthy NN Jarjour EA Kelly RR Rodriguez WW Busse 《Canadian Metallurgical Quarterly》1997,17(8):481-487
T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation. 相似文献
103.
PURPOSE: Oxidative stress and other forms of injury to trabecular meshwork (TM) cells may contribute to changes seen with age and primary open-angle glaucoma. This study was designed to investigate if TM expresses alpha B-crystallin, a small heat-shock protein with chaperone activity, and whether it might be overexpressed under stress conditions. METHODS: The TM from human and monkey eyes, as well as organ and primary cell cultures derived from these eyes, were investigated for alpha B-crystallin by immunohistochemistry, two-dimensional gel electrophoresis, Northern and Western blot analysis. The TM cell cultures were stressed by heat shock (44 degrees C for 15 minutes) or hydrogen peroxide (200 mumol for 1 hour). Semiquantitation of alpha B-crystallin messenger RNA (mRNA) or protein was obtained by densitometry. RESULTS: In both species, alpha B-crystallin could be detected in fresh and cultured TM by two-dimensional gel electrophoresis in conjunction with Western blot analysis. Immunohistochemistry of fresh samples showed that alpha B-crystallin was expressed predominantly in the cribriform area. Protein expression was enhanced in 4- to 7-day organ cultures. Primary cultures from human TM cells expressed two sizes (approximately 0.8 and 1.1 kb) of alpha B-crystallin mRNA in Northern blots. In monkey TM cultures, a 0.8-kb band was observed, which comigrated with lens alpha B-crystallin. In both species, heat shock caused a significant increase in alpha B-crystallin mRNA with a peak after 4 hours. An increase in alpha B-crystallin mRNA also was observed after oxidative stress; however, the onset of mRNA induction was slower. After heat shock, but not after oxidative stress, a transient change in mRNA mobility was observed. Western dot blot analysis showed a 3.4-fold increase in protein 24 hours after heat shock and a 20-fold increase after 48 hours. No constitutive mRNA expression and only a minimal increase 4 hours after heat shock could be observed in simian virus 40 transformed cell lines from human TM. CONCLUSIONS: Overexpression of alpha B-crystallin might be an important mechanism for TM to prevent cellular damage associated with various stress conditions. 相似文献
104.
A Bedekar RM Zink DH Sherman TV Line JF Van Pilsum 《Canadian Metallurgical Quarterly》1998,119(4):677-690
The amino acid sequences of the amidinotransferases and the nucleotide sequences of their genes or cDNA from four Streptomyces species (seven genes) and from the kidneys of rat, pig, human and human pancreas were compared. The overall amino acid and nucleotide sequences of the prokaryotes and eukaryotes were very similar and further, three regions were identified that were highly identical. Evidence is presented that there is virtually zero chance that the overall and high identity regions of the amino acid sequence similarities and the overall nucleotide sequence similarities between Streptomyces and mammals represent random match. Both rat and lamprey amidinotransferases were able to use inosamine phosphate, the amidine group acceptor of Streptomyces. We have concluded that the structure and function of the amidinotransferases and their genes has been highly conserved through evolution from prokaryotes to eukaryotes. The evolution has occurred with: (1) a high degree of retention of nucleotide and amino acid sequences; (2) a high degree of retention of the primitive Streptomyces guanine + cytosine (G + C) third codon position composition in certain high identity regions of the eukaryote cDNA; (3) a decrease in the specificities for the amidine group acceptors; and (4) most of the mutations silent in the regions suggested to code for active sites in the enzymes. 相似文献
105.
106.
SC Shim DH Yoo JK Lee HK Koh SR Lee SH Oh SY Kim 《Canadian Metallurgical Quarterly》1998,25(12):2464-2468
Ankylosing spondylitis (AS) results in disease-specific inflammation at the site of ligamentous insertion into the bone. Atlantoaxial joint subluxation and vertical subluxation of the axis may occur as a consequence of instability resulting from the inflammatory process. Spontaneous anterior atlantoaxial subluxation is a well recognized complication in about 2% of patients with AS, and presents with or without signs of spinal cord compression. Vertical subluxation may follow anterior or posterior subluxation. It was noted in 3-8% of patients with rheumatoid arthritis, but is an exceedingly rare complication of AS. Moreover, it has never been reported that multiple cerebellar infarction and bulbar symptoms developed spontaneously due to atlanto-occipital subluxation and vertical subluxation in a patient with a long [corrected] history of AS. We describe a man with AS who developed multiple cerebellar infarction due to vertebral artery obstruction and bulbar symptoms associated with atlanto-occipital subluxation and vertical subluxation. 相似文献
107.
M Lussier AM White J Sheraton T di Paolo J Treadwell SB Southard CI Horenstein J Chen-Weiner AF Ram JC Kapteyn TW Roemer DH Vo DC Bondoc J Hall WW Zhong AM Sdicu J Davies FM Klis PW Robbins H Bussey 《Canadian Metallurgical Quarterly》1997,147(2):435-450
The sequenced yeast genome offers a unique resource for the analysis of eukaryotic cell function and enables genome-wide screens for genes involved in cellular processes. We have identified genes involved in cell surface assembly by screening transposon-mutagenized cells for altered sensitivity to calcofluor white, followed by supplementary screens to further characterize mutant phenotypes. The mutated genes were directly retrieved from genomic DNA and then matched uniquely to a gene in the yeast genome database. Eighty-two genes with apparent perturbation of the cell surface were identified, with mutations in 65 of them displaying at least one further cell surface phenotype in addition to their modified sensitivity to calcofluor. Fifty of these genes were previously known, 17 encoded proteins whose function could be anticipated through sequence homology or previously recognized phenotypes and 15 genes had no previously known phenotype. 相似文献
108.
109.
PR Gibson D Kilias O Rosella JM Day M Abbott CF Finch GP Young 《Canadian Metallurgical Quarterly》1998,94(6):671-676
Public awareness and misunderstandings of lactose intolerance are at an all-time high. Many people erroneously believe they are lactose intolerant or develop gastrointestinal symptoms after intake of lactose. Consequently, lactose-containing foods such as milk and other dairy foods may be eliminated unnecessarily from the diet. Because these foods are a major source of calcium, low intake of them can compromise calcium nutriture. This, in turn, can increase the risk of major chronic diseases such as osteoporosis (porous bones) and hypertension. This review is intended to help dietetics professionals alleviate clients' fears about lactose intolerance and recommend dietary strategies to improve tolerance to lactose. Scientific findings indicate that the prevalence of lactose intolerance is grossly overestimated. Other physiologic and psychologic factors can contribute to gastrointestinal symptoms that mimic lactose intolerance. Scientific findings also indicate that people with laboratory-confirmed low levels of the enzyme lactase can consume 1 serving of milk with a meal or 2 servings of milk per day in divided doses at breakfast and dinner without experiencing symptoms. Several dietary strategies are available to help lactose maldigesters include milk and other dairy foods in their diet without experiencing symptoms. 相似文献
110.
Berninger Virginia W.; Vaughan Katherine; Abbott Robert D.; Brooks Allison; Abbott Sylvia P.; Rogan Laura; Reed Elizabeth; Graham Steve 《Canadian Metallurgical Quarterly》1998,90(4):587
Poor spellers in 2nd grade (n?=?128) participated in 24 20-min sessions that included (a) direct instruction in the alphabet principle (most frequent phoneme-spelling connections); (b) modeling of different approaches, singly and in combination, for developing connections between spoken and written words for 48 words ordered by sound-spelling predictability; and (c) practice in composing. Results of this multilayered intervention showed that (a) more than 1 way of developing sound-spelling connections is effective in teaching spelling but that after training in the alphabet principle, combining whole word and onset-rime training is most effective in achieving transfer of the alphabet principle across word contexts; (b) functional spelling units of not only a single letter but also 2 or more letters are important in beginning spelling; and (c) training in spelling transfers to composition and word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献