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In Clione limacina, locomotory rhythm is produced in the central pattern generator by reciprocal activity of two groups of interneurons. Dorsal (D) and ventral (V) phase interneurons activate neurons of the same phase and inhibit neurons of the opposite phase. Which neurotransmitters are used by these interneurons is not clear. In this study, identified follower neurons to V and D interneurons were isolated, and their responses to the local application of potential neurotransmitters were examined. Acetylcholine exerted inhibitory action on the isolated D-phase neurons and excitatory action on V-phase neurons. Glutamate produced excitation in D-phase neurons, and inhibition in V-phase neurons. These results suggest that acetylcholine is the neurotransmitter of D-phase interneurons, while glutamate might be the neurotransmitter of V-phase interneurons. 相似文献
3.
Urs E. Gattiker 《Behaviour & Information Technology》1988,7(4):345-359
Organizational adjustment to technological change and its impact upon human resources should be based on an understanding of employee perceptions and behavioural responses to such developments. An analytic framework which relates strategic choice to internal labour market and employee determinism is derived from the methods employed by organizational theorists and psychologists to generate a set of typologies. The framework divides variables in four classes: (1) natural selection, with minimum choice and adaptation or selection out; (2) differentiation, with high choice and high employee determinism and adaptation within constraints; (3) strategic choice, with maximum choice and adaptation by design; and (4) undifferentiated choice, with incremental choice and adaptation by chance. Useful in reconciling previously inconsistent or incompatible theories of technological change, the framework is offered as a co-ordination device to integrate the results of divergent approaches to technological adaptation studies. 相似文献
4.
AT Goodwin J Tully C Charlesworth RI Swift SJ Chadwick 《Canadian Metallurgical Quarterly》1997,51(3):140-143
Progressive supranuclear palsy (PSP) is a progressive degenerative extrapyramidal disease that often masquerades as Parkinson's disease (PD). Similar to PD, dysphagia frequently complicates the course of PSP. Because there is only one published report characterizing dysphagia in PSP, we reviewed the neurologic features and dynamic videofluoroscopic swallowing function study results in 10 dysphagic PSP patients. Abnormalities during multiple stages of ingestion were recorded in each patient. Uncoordinated lingual movements, absent velar retraction or elevation, impaired posterior lingual displacement, and copious pharyngeal secretions were noted in all patients. Tongue-assisted mastication, noncohesive lingual transfer, excessive oral bolus lingual leakage to the pharynx prior to active transfer, vallecular bolus retention, abnormal epiglottic positioning, and hiatal hernias were noted in at least half of the cohort. Although ingestion abnormalities in PSP are similar to those previously reported in PD, the number of studied patients and observed differences were too few to clearly differentiate the two diseases. 相似文献
5.
EK Khusnutdinova TV Viktorova IM Khidiiatova RI Fatkhlislamova TE Ivashchenko 《Canadian Metallurgical Quarterly》1997,33(9):1291-1296
Data on allelic polymorphism of MET and D7S23 DNA loci linked to the human cystic fibrosis gene studied in three Bashkir ethnic groups and some Volga-Ural populations (Tartars, Maris, Mordovians, Udmurts, Chuvashs, and Komis) are presented. Udmurts were found to be substantially different from Bashkirs, Tartars, Mordovians, and Chuvashs by the allele frequency distribution observed for MET, while Komis and Bashkirs differed by this parameter from Mordovians and Maris. Comparative analysis of restriction fragment length polymorphism (RFLP) at the D7S23 locus revealed statistically significant differences in genotype frequencies between Bashkirs of the Arkhangel' skii region and populations of Mordva and Udmurtia. In this respect, the Mordovian population appeared to be notably different from the populations of Bashkortostan, Tatarstan, Marii-El, Udmurtiya, Chuvashiya, and Komis. Genetic distances were calculated and corresponding dendrograms were constructed on the basis of data on Met-H, CS.7, and the ApoB locus hypervariable region allelic frequencies. Three ethnogeographic Bashkir groups belonging to one tree branch were found to be closely related to the populations of Tartars, Maris, Udmurts, and Chuvashs and substantially different from Komis and Mordovians. Thus, the position of Volga-Ural populations on the dendrogram corresponds to the degree of relationship between the Finno-Ugric and Turkic populations, confirming the usefulness of DNA polymorphism analysis for the study of the genetic structure of populations. 相似文献
6.
Urs E. Gattiker 《Journal in Computer Virology》2007,3(2):149-161
The Bologna process has resulted in the re- structuring of undergraduate and graduate education across Europe. This paper outlines what these changes mean for acquiring degrees in information security and how various universities have tried to respond to these demands. What is unclear at this stage is how the offering of continuous master degrees at Polytechnic and Applied Science Universities will affect the content and curriculum being taught in computer science and information security in particular. This question must be addressed since polytechnics are more industry focused and less research oriented than their university-counterparts. What seems to be clear at this stage is that continuous type master programs in computer science demand a greater level of mathematical knowledge than specialized masters. Moreover, due to the amount of credits that must be acquired, graduates of these types of programs will bring a deeper knowledge about the specialization such as, information security or malware, they acquired at university. This movement toward greater convergence in post secondary education may not have made things easier for recruiters, who are trying to hire graduates in information security or anti-virus experts. In fact, as this paper shows while the Bologna process may have eliminated the obvious differences, countless intricate and not so obvious differences have been added making it sometimes obscure for a bystander. 相似文献
7.
8.
R Hui JR Ball RD Macmillan FS Kenny OW Prall DH Campbell AL Cornish RA McClelland RJ Daly JF Forbes RW Blamey EA Musgrove JF Robertson RI Nicholson RL Sutherland 《Canadian Metallurgical Quarterly》1998,17(8):1053-1059
The EMS1 and CCND1 genes at chromosome 11q13 are amplified in about 15% of primary breast cancers but appear to confer different phenotypes in ER positive and ER negative tumours. Since there are no published data on EMS1 expression in large series of breast cancers we examined the relationship of EMS1 expression with EMS1 gene copy number and expression of mRNAs for cyclin D1 and ER. In a subset of 129 patients, where matched tumour RNA and DNA was available, EMS1 mRNA overexpression was associated predominantly with gene amplification (P = 0.0061), whereas cyclin D1 mRNA overexpression was not (P = 0.3142). In a more extensive series of 351 breast cancers, there was no correlation between cyclin D1 and EMS1 expression in the EMS1 and cyclin D1 overexpressors (P = 0.3503). Although an association between EMS1 mRNA expression and ER positivity was evident (P = 0.0232), when the samples were divided into quartiles of EMS1 or cyclin D1 mRNA expression, the increase in the proportion of ER positive tumours in the ascending EMS1 mRNA quartiles was not statistically significant (P = 0.0951). In marked contrast there was a significant stepwise increase in ER positivity in ascending quartiles of cyclin D1 mRNA (P = 0.030). A potential explanation for this difference was provided by the observation that in ER positive breast cancer cells oestradiol treatment resulted in increased cyclin D1 gene expression but was without effect on EMS1. The relationship between EMS1 expression and clinical outcome was examined in a subset of 234 patients with median follow-up of 74 months. High EMS1 expression was associated with age > 50 years (P = 0.0001), postmenopausal status (P = 0.0008), lymph node negativity (P = 0.019) and an apparent trend for worse prognosis in the ER negative subgroup. These data demonstrate that overexpression of EMS1 mRNA is largely due to EMS1 gene amplification, is independent of cyclin D1 and ER expression and, in contrast to cyclin D1, is not regulated by oestrogen. Independent overexpression of these genes may confer different phenotypes and disease outcomes in breast cancer as has been inferred from recent studies of EMS1 and CCND1 gene amplification. 相似文献
9.
RI Senderoff KM Kontor L Kreilgaard JJ Chang S Patel J Krakover JK Heffernan LB Snell GB Rosenberg 《Canadian Metallurgical Quarterly》1998,87(2):183-189
This article summarizes the results of a combined analysis from two identical multicenter clinical trials that investigated the efficacy and safety of sertraline versus placebo for treating panic disorder. Patients with panic disorder who were treated with sertraline had a statistically significant reduction in the mean number of panic attacks per week (the primary efficacy measure) as compared with placebo (4.8 vs. 2.5, p < .001). Sertraline-treated patients also showed greater improvement that was statistically significant on several ratings of panic disorder symptomatology and functioning. The design characteristics, clinical rating measures, and outcome measures in these trials included most of the features deemed essential by Shear and Maser (1994) in their summary of the NIMH Consensus Conference for the development of standardized assessments for panic disorder. This suggests that the NIMH Consensus Conference played a key role in developing successful multicenter pharmacological treatment studies, such as this one that ultimately demonstrated that sertraline was an effective treatment for panic disorder. 相似文献
10.
MI Aguilar DJ Clayton P Holt V Kronina RI Boysen AW Purcell MT Hearn 《Canadian Metallurgical Quarterly》1998,70(23):5010-5018
Procedures have been developed to identify the chromatographic binding domains of horse heart cytochrome c (Cyt c) and bovine growth hormone (bGH) during their interaction with reversed-phase sorbent materials. The procedure involves adsorption of the protein solute to the chromatographic sorbent, followed by proteolytic cleavage. Comparison of the proteolytic map obtained for Cyt c and bGH in free solution with the corresponding map obtained when these proteins are adsorbed to the chromatographic sorbent revealed significant differences in the digestion pattern. Following characterization of the peptides generated in both maps, the results indicated that specific regions on the surface of both Cyt c and bGH are inaccessible to tryptic cleavage when adsorbed to the hydrophobic surface of both a C-4 and a C-18 sorbent. Based on the assumption that the region of the protein surface that is in contact with the sorbent remains intact and bound to the sorbent during the digestion step, while the protein surface that is exposed to the solvent is accessible to proteolysis, the regions that were inaccessible to tryptic digestion were found to correspond to hydrophobic domains on the protein surface. These results also suggest that the three-dimensional structures of these proteins remain largely intact upon adsorption to the hydrophobic surface. 相似文献