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131.
SS Tseng PL Weaver Y Liu M Hitomi AM Tartakoff TH Chang 《Canadian Metallurgical Quarterly》1998,17(9):2651-2662
The DBP5 gene encodes a putative RNA helicase of unknown function in the yeast Saccharomyces cerevisiae. It is shown here that Dbp5p is an ATP-dependent RNA helicase required for polyadenylated [poly(A)+] RNA export. Surprisingly, Dbp5p is present predominantly, if not exclusively, in the cytoplasm, and is highly enriched around the nuclear envelope. This observation raises the possibility that Dbp5p may play a role in unloading or remodeling messenger RNA particles (mRNPs) upon arrival in the cytoplasm and in coupling mRNP export and translation. The functions of Dbp5p are likely to be conserved, since its potential homologues can be found in a variety of eukaryotic cells. 相似文献
132.
AP Colombo C Eftimiadi AD Haffajee MA Cugini SS Socransky 《Canadian Metallurgical Quarterly》1998,25(6):465-474
The purpose of this investigation was to compare the levels of serum IgG2, the frequency of detection of Gm(23)-negative allotype and frequency of detection of FcgammaRIIa and FcgammaRIIIb receptor haplotypes in 32 refractory, 54 successfully treated and 27 periodontally healthy individuals. Refractory subjects showed mean full mouth attachment loss and/or >3 sites with attachment loss >2.5 mm within 1 year after both scaling and root planing, and surgery plus systemically administered tetracycline. Successfully treated subjects showed mean attachment level gain and no sites with attachment loss >2.5 mm 1 year post-therapy. Periodontally healthy subjects exhibited no pocket depth or attachment level >3 mm, and no evidence of progressing disease during 1 year of monitoring. Blood was obtained from each subject at baseline. Serum IgG2 and Gm(23) allotype were determined using radial immunodiffusion. DNA was extracted from whole blood and the FcgammaR genotypes determined using PCR and allele specific oligonucleotide probes. Significance of differences among clinical groups were sought using the Kruskal-Wallis or chi-square tests. Associations between 2 or more variables were tested using regression analysis. Refractory subjects exhibited higher mean attachment loss and pocket depth than successfully treated or periodontally healthy subjects. Smoking status did not differ significantly among groups. No significant differences in serum IgG2 levels and frequency of detection of Gm(23)-negative allotype were observed among the clinical groups. Serum IgG2 level was positively associated with the number of serum antibody responses to subgingival species (r=0.51, p<0.001). Subjects with the Gm(23)-negative allotype exhibited lower mean levels of serum IgG2 (3.06+/-0.3 versus 3.9+/-0.2, p<0.01) and mean number of serum antibodies to subgingival species (17.7+/-1.7 versus 23.3+/-1.4, p<0.05) than allotype positive individuals. No significant differences in FcgammaR haplotype distribution were observed among the 3 clinical groups. Associations of serum IgG2 level, Gm(23) allotype, FcgammaRIIa and FcgammaRIIIb receptor haplotypes and smoking status were weakly related or not related to clinical status. This lack of relationship may have been due to a reality of no relationship, or the inadvertent pooling of subjects where these factors were of primary importance with subjects in whom these factors played a less important role. 相似文献
133.
OBJECTIVE AND IMPORTANCE: We report a unique case of ivory osteoma of the cervical spine. CLINICAL PRESENTATION: The clinical presentation was one of polyradicular deficit without myelopathy after trauma. The imaging characteristics and histology of the lesion were those of a classic ivory osteoma. INTERVENTION: A complete surgical excision of the lesion was accomplished. CONCLUSION: We think we have recorded the only well-documented case of ivory osteoma affecting the spine. 相似文献
134.
MC Lipman D Stobbs S Madge R Miller MA Johnson 《Canadian Metallurgical Quarterly》1998,114(1):284-290
STUDY OBJECTIVES: Asymptomatic HIV-infected individuals are increasingly recruited for studies involving invasive procedures such as bronchoscopy. We sought to determine the response to and outcome of a request for a research bronchoscopy in HIV-positive individuals with no respiratory disease, and whether this would adversely affect future decisions to have a medically indicated bronchoscopy. DESIGN AND SETTING: Prospective, semistructured, questionnaire-based study in a London teaching hospital HIV outpatient clinic. PARTICIPANTS: One hundred and seven consecutive HIV-infected eligible individuals. Thirty-one healthy volunteers served as a control group for the subjective response to bronchoscopy. MAIN OUTCOME MEASURES: Subjects' attitudes and responses to requests for bronchoscopy and subsequent behavior when they required medically indicated bronchoscopy. RESULTS: Seventy-five patients (70%) agreed to the procedure in principle, predominantly for altruistic reasons. Thirty-nine subjects underwent bronchoscopy. Five percent found it worse than expected; and 79% agreed to another research bronchoscopy (performed in 11 subjects approximately 2 years later). All patients said they would undergo bronchoscopy again for diagnostic purposes (required in seven during the study). When compared to a healthy volunteer population within the same study, postbronchoscopy symptoms were similar in frequency although somewhat different in nature. Subjects felt that a clear explanation of what was involved enhanced their participation in this research. CONCLUSIONS: Invasive research procedures such as bronchoscopy can be performed and are repeatable in a healthy HIV-infected population. Performance of procedures for research purposes does not appear to adversely affect future health-care decisions. 相似文献
135.
PURPOSE: To determine the frequency of remission in patients with essential blepharospasm and Meige syndrome. METHOD: Retrospective analysis of patients by means of questionnaire in an institutional setting. RESULTS: Among 238 patients diagnosed in a single institution as having essential blepharospasm or Meige syndrome, 27 (11.3%) claimed to be symptom free without curative surgery. The average time between onset and resolution in the patients who claimed remission was 4.85 years (range, 3 months to 22 years). Among these patients, the duration of remission averaged 6.33 years (range, 1 year to 14 years). CONCLUSION: Patients with essential blepharospasm or Meige syndrome have a small but definite potential for spontaneous remission of symptoms, particularly within the first 5 years after onset of symptoms. 相似文献
136.
This paper presents a multifaceted method for teaching engineering mechanics designed to satisfy the following set of desiderata: (1) integrate engineering practice into the teaching of engineering science; (2) address a wide set of learning styles; (3) provide opportunities for practice in group work and learning; (4) promote communication and synthesizing skills; (5) engage students in the teaching and learning process; (6) maintain traditional achievement levels with respect to traditional measures; (7) motivate students to continue their engineering studies; and (8) maintain reasonable resource demands. Consistent with this variety of objectives, the approach presented here is composed of a variety of ingredients. In addition to the standard homework problems and exams, these ingredients include design projects, group work, basic competency exams, computational environments for simulating and visualizing phenomena, multimedia instructional tools, hands-on experiences, and student presentations. This educational model is intended to be suitable for teaching engineering mechanics in general, but this paper focuses on a particular sophomore-level mechanics of materials course in which the method has been implemented, refined over several years of classroom use, and tested relative to traditional approaches. The paper describes the and techniques that together make up the method, followed by summaries of the results of evaluations that have been applied to the course. 相似文献
137.
138.
139.
Influenza caused low levels of mortality and morbidity in England and Wales in the 1997/98 season. Influenza viruses of the H3N2 and H1N1 subtypes were isolated in small numbers from community and hospital patients in November and December. Their numbers subsequently increased to peak in February, H1N1 a week or two before H3N2. Most of the H1N1 isolates were similar to the A/Bayern/7/95-like virus, included in the vaccine recommended for 1997-98, whereas most H3N2 isolates were A/Sydney/5/97-like, a virus not covered by the season's vaccine but recommended for 1998/99. Consultation rates in general practice for influenza-like illnesses remained low until early February, when a small increase coincided with the increase in laboratory confirmed influenza. Fewer deaths directly attributed to influenza were registered during the surveillance period than in recent years. Localised outbreaks occurred in schools and nursing homes towards the end of the winter. 相似文献
140.
JW Erdman AJ Thatcher NE Hofmann JD Lederman SS Block CM Lee S Mokady 《Canadian Metallurgical Quarterly》1998,128(11):2009-2013
The algae Dunaliella bardawil and Dunaliella salina naturally contain large concentrations of all-trans and 9-cis beta-carotene (betaC). The purpose of this study was to compare the relative serum and tissue accumulation of all-trans and 9-cis betaC in ferrets fed different ratios of all-trans/9-cis betaC derived from two commercial sources, D. bardawil or D. salina (Betatene). Male ferrets (7 wk old) were fed carotene-free, pelleted diets for 27 d. Beginning on d 18, groups of ferrets (n = 6 or 7) received daily, one of six oral supplements varying in ratios of 9-cis and all-trans betaC mixed with approximately 1.0mL of Ensure. Four supplements containing 5.2-8.3 micromol total betaC were prepared from a 20% Betatene preparation, D. bardawil, a high-cis Betatene preparation, and Betatene further enriched in 9-cis betaC with all-trans betaC/9-cis betaC ratios of 2.2, 1.5, 0.6 and 0.4, respectively. Two control supplements, high and low betaC, were prepared from commercial betaC beadlets. The high control supplement had an all-trans/9-cis ratio of 19.0, whereas 9-cis betaC was not detected in the low supplement. On d 27, serum and tissues were obtained for HPLC analysis of betaC and its isomers. Analysis of livers showed that all-trans betaC was the primary isomer present, but 9-cis and other isomers were also detected in all groups. The hepatic all-trans/9-cis ratios were 5.9, 4.9, 2.5, 1.4, 52.2 and47.5, respectively, for the groups listed above. Lower amounts of all-trans and 9-cis betaC were found in kidneys compared with the liver, but ratios of all-trans/9-cis were not different among groups. Only trace amounts of 9-cis betaC were found in serum. These results demonstrate that the algae D. bardawil and D. salina provide a bioavailable source of betaC isomers, but, as in humans, absorption of 9-cis betaC is poor and any 9-cis betaC absorbed is apparently cleared by the liver. 相似文献