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101.
To identify genes necessary for establishing connections in the Drosophila sensory nervous system, we designed a screen for mutations affecting development of the larval visual system. The larval visual system has a simple and stereotypic morphology, can be recognized histologically by a variety of techniques, and is unnecessary for viability. Therefore, it provides an opportunity to identify genes involved in all stages of development of a simple, specific neuronal connection. By direct observation of the larval visual system in mutant embryos, we identified 24 mutations affecting its development; 13 of these are larval visual system-specific. These 13 mutations can be grouped phenotypically into five classes based on their effects on location, path or morphology of the larval visual system nerves and organs. These mutants and phenotypic classifications provide a context for further analysis of neuronal development, pathfinding and target recognition. 相似文献
102.
I Kabir MM Rahman R Haider RN Mazumder MA Khaled D Mahalanabis 《Canadian Metallurgical Quarterly》1998,128(10):1688-1691
The impact of dietary supplementation on catch-up growth was evaluated in 69 malnourished children ages 24-60 mo after recovery from shigellosis. They were fed either a high-protein (HP) diet with 15% of energy as protein, or a standard-protein (SP) diet with 7.5% energy as protein, for 3 wk in a metabolic study ward. Children were followed up bi-weekly for 6 mo by trained health assistants when anthropometric measurements and information of any illness were collected. Thirty-one children in the HP group and 28 children in the SP group completed 6-mo follow-up. The increase in height (mean +/- SD) was 5.3 +/- 1.0 cm vs. 4.1 +/- 1.1 cm for HP and SP groups, respectively (P < 0.001), whereas increase in body weight was 1.39 +/- 0.58 and 1.29 +/- 0.72 kg for children fed HP and SP, respectively (P = 0.59). The proportion of children who were severely stunted (< -2 SD height-for-age) decreased from 45 to 29% in the HP group compared to 50 to 46% in the SP group (P < 0.05) at 6-mo follow-up. The number of diarrheal episodes per child tended to be lower in the HP vs. SP than in the SP group (1.9 vs. 2.3, P = 0.41). These results demonstrate that feeding an HP diet to the malnourished children during recovery from shigellosis enhanced linear growth with a modest reduction in diarrheal morbidity during the 6-mo follow-up period. 相似文献
103.
EJ Bilsky RN Bernstein GW Pasternak VJ Hruby D Patel F Porreca J Lai 《Canadian Metallurgical Quarterly》1994,55(2):PL37-PL43
Evidence in vivo has suggested the existence of subtypes of the delta opioid receptor (DOR), which have been termed delta 1 and delta 2. These proposed DOR subtypes are thought to be activated by [D-Pen2, D-Pen5]enkephalin (DPDPE, delta 1) and [D-Ala2, Glu4]deltorphin (delta 2). Recent work in which an antisense oligodeoxynucleotide (oligo) to a cloned DOR was administered by the intrathecal (i.th.) route has demonstrated a reduction in the antinociceptive actions of both i.th. DPDPE and [D-Ala2, Glu4]deltorphin, but not of [D-Ala2, NMPhe4, Gly-ol]enkephalin (DAMGO, mu agonist) in mice. The present investigation has extended these observations by administering the same DOR antisense oligo sequence by the intracerebroventricular (i.c.v.) route and evaluating the antinociceptive actions of i.c.v. agonists selective for delta, mu and kappa receptors. I.th. treatment with DOR antisense oligo, but not mismatch oligo, significantly inhibited the antinociceptive actions of both i.th. DPDPE and [D-Ala2, Glu4]deltorphin but not of i.th. DAMGO or U69,593 (kappa agonist), confirming previous data. In contrast, i.c.v. DOR antisense oligo, but not mismatch oligo, selectively inhibited the antinociceptive response to i.c.v. [D-Ala2, Glu4]deltorphin without altering the antinociceptive actions of i.c.v. DPDPE, DAMGO or U69,593. The data suggest that the cloned DOR corresponds to that pharmacologically classified as delta 2 and further, suggest that this delta receptor subtype may play a major role in eliciting spinal delta-mediated antinociception. 相似文献
104.
RN Clayton M Boggild AS Bates J Bicknell D Simpson W Farrell 《Canadian Metallurgical Quarterly》1997,47(4-6):185-193
Abnormal cell proliferation is controlled by opposing actions of oncogene products (stimulatory) and tumour suppressor gene (TSG) products (inhibitory). The former are dominantly acting, i.e. only one copy needed for tumorigenesis, whilst for TSG both copies of the gene must be inactivated so these are recessive at a cellular level. For anterior pituitary tumours only one oncogene (Gsp) has been identified in a variable proportion (4-40%) of a single tumour subtype (somatotrophinomas). Contrariwise, allelic deletion studies, using a PCR-based microsatellite polymorphism analysis of DNA extracted from archival specimens, have shown significant loss of heterozygosity in 20-40% of all tumour subtypes at the locus of the putative MEN-1 gene (chr. 11q13); the retinoblastoma gene (chr. 13q 12-14), and 10q26. Moreover, these DNA microdeletions were concentrated in radiologically invasive tumours compared to noninvasive tumours (modified Hardy gdes 3 and 4 vs. 1 + 2). In addition, 50% of Cushing's adenomas showed presence of p53 immunopositivity, though no point mutations in exons 4-9 were found, by SSCP analysis, to account for this. These studies show that analysis of TSGs in pituitary adenomas may provide clues to their pathogenesis, and more importantly relate to clinical behaviour of the tumour, and hence aid decisions regarding management. 相似文献
105.
RN Gunn PA Sargent CJ Bench EA Rabiner S Osman VW Pike SP Hume PM Grasby AA Lammertsma 《Canadian Metallurgical Quarterly》1998,8(4):426-440
[Carbonyl-11C]WAY-100635 is a promising PET radioligand for the 5-HT1A receptor, having demonstrated more favorable characteristics for in vivo imaging than the previously available [O-methyl-11C]WAY-100635. The current study evaluates different tracer kinetic modelling strategies for the quantification of 5-HT1A receptor binding in human brain. Mathematical modelling of the carbonyl-labeled radiotracer is investigated using compartmental structures, including both plasma input and reference tissue approaches. Furthermore, the application of basis function methods allows for the investigation of parametric imaging, providing functional maps of both delivery and binding of the radioligand. Parameter estimates of binding from normal volunteers indicate a low intra- versus a high intersubject variability. It is concluded that a simplified reference tissue approach may be used to quantify 5-HT1A binding either in terms of ROI data or as parametric images. 相似文献
106.
TA Dingus MC Hulse MA Mollenhauer RN Fleischman DV McGehee N Manakkal 《Canadian Metallurgical Quarterly》1997,39(2):177-199
This paper explores the effects of age, system experience, and navigation technique on driving, navigation performance, and safety for drivers who used TravTek, an Advanced Traveler Information System. The first two studies investigated various route guidance configurations on the road in a specially equipped instrumented vehicle with an experimenter present. The third was a naturalistic quasi-experimental field study that collected data unobtrusively from more than 1200 TravTek rental car drivers with no in-vehicle experimenter. The results suggest that with increased experience, drivers become familiar with the system and develop strategies for substantially more efficient and safer use. The results also showed that drivers over age 65 had difficulty driving and navigating concurrently. They compensated by driving slowly and more cautiously. Despite this increased caution, older drivers made more safety-related errors than did younger drivers. The results also showed that older drivers benefited substantially from a well-designed ATIS driver interface. 相似文献
107.
RN Jones MA Pfaller SA Marshall RJ Hollis WW Wilke 《Canadian Metallurgical Quarterly》1997,29(3):187-192
From March 1989 to March 1993, six athletic patients were treated in our institution by thrombolytic therapy for acute effort axillary-subclavian vein thrombosis in thoracic outlet syndrome. Mean age of these patients was 20 (range 14 to 27). An in situ infusion with urokinase (2,500 U/kg/h) and Heparin (100 U/kg/12 hours) was given during 64 hours (Range 14 to 72). Phlebography showed a complete reperfusion in three cases (the treatment began within an average period of 5.6 days), partial reperfusion in two cases (the treatment began within an average period of 8.5 days). In one case there was no reperfusion on phlebography: treatment began within an average period of 15 days. For this patient, a venous axillo-jugular bypass graft was performed. In all cases, there was no bleeding complication. A trans-axillary first rib resection was done three months later. Mean follow up was 31 months (range: two to 51 months). All patients recovered their previous physical status. Echo-Doppler exam showed normal subclavian vein flow in four cases, partial occlusion in one case and a total occlusion of the subclavian vein flow in one case. In this last case, the thrombolytic therapy failed to restore the permeability of the subclavian vein. Bypassgraft was patent. Axillary-subclavian vein thrombosis seen within a period of seven days should be treated by local thrombolytic therapy using urokinase and heparin. 相似文献
108.
CM Craft J Xu VZ Slepak X Zhan-Poe X Zhu B Brown RN Lolley 《Canadian Metallurgical Quarterly》1998,37(45):15758-15772
In this study, we identify new isoforms of the retinal phosducin and investigate the expression of the phosducin family, showing that an isoform, PhLP1, has sequence homology with Phd and Gbeta gamma binding capability, whereas two isoforms (phosducin-like orphan proteins, PhLOPs) share sequence homology with Phd but fail to bind Gbeta gamma. Original identification of PhLP1 and the PhLOPs was from a human retina cDNA library, using a PCR product for library hybridization screening that contained a predicted functional epitope domain. The screen identified Phd and three related, but distinct, recombinants (PhLP1, PhLOP1, and PhLOP2). By RT-PCR, all isoforms are expressed in either retina or forskolin-stimulated Y79 retinoblastoma cells; however, the new isoforms are below the level of detection on Northern blot analysis. The predicted amino acid translation of each homologue revealed major differences, arising from either splice variants or gene duplication of Phd. To test the functional interaction of all phosducin isoforms with Gbeta gamma in vitro, a glutathione S-transferase (GST) fusion protein was developed for each member. Biochemical interaction with purified retinal transducin Gbeta gamma was verified for GST-Phd and demonstrated for GST-PhLP1; however, neither GST-PhLOP1 nor GST-PhLOP2 bound Gbeta gamma. Comparable results were observed when the GST-phosducin fusion proteins selectively sequestered Gbeta gammas from retinal extracts or when functional Gbeta gamma interactions were assessed using surface plasmon resonance technology. Phosducin and its isoforms are widely distributed in body tissues where they may participate in signal transduction pathways. Phd and PhLP1 possess an 11-amino acid conserved epitope domain (TGPKGVINDWR) that controls the high-affinity binding of Gbeta gamma; these isoforms are implicated in the G-protein signaling pathway. The phosducin-like orphan proteins (PhLOPs) fail to bind Gbeta gamma, suggesting that the PhLOP isoforms may participate in still unidentified signaling pathways. 相似文献
109.
RN Emde 《Canadian Metallurgical Quarterly》1998,48(3-4):114-127
Contributions of Sigmund Freud and René Spitz to developmental psychology are presented in terms of today's research. The work of each of these pioneers draws our attention to the need for increasing our knowledge about the meaning of individual experience and increasing complexity in the course of development. Freud's contribution to today's developmental thinking is reviewed in terms of his observations of play, his schematic perspectives on developmental processes, and his innovative theoretical approaches involving nonconscious mental activity in the context of constructivism. Spitz's contribution to today's thinking is reviewed according to a similar array of topics. These include his observational assessments of infants, his schematic perspectives on developmental processes, and his innovative theoretical approaches involving affective communications in the context of caregiving. 相似文献
110.
GW Hart LK Kreppel FI Comer CS Arnold DM Snow Z Ye X Cheng D DellaManna DS Caine BJ Earles Y Akimoto RN Cole BK Hayes 《Canadian Metallurgical Quarterly》1996,6(7):711-716
BACKGROUND: Registered mortality from cryptogenic fibrosing alveolitis (CFA) in England and Wales has increased substantially since the specific International Classification of Diseases code for CFA was introduced in 1979. However, since a significant proportion of deaths from CFA are misclassified as post inflammatory fibrosis (PIF), it is possible that the observed rise in CFA mortality is due to diagnostic transfer from this code. To investigate this, and to assess mortality trends in other countries, annual CFA and PIF mortality data from England and Wales, USA, Australia, Scotland, Canada, New Zealand, and Germany were analysed. METHODS: Crude annual mortality rates were calculated and rates standardised by Poisson regression to allow assessment of changes over time and comparison between countries, sexes, and age groups. The relative trends in mortality from CFA and PIF were assessed by calculating the annual ratio of CFA to PIF deaths. RESULTS: Men were more likely than women to die from both CFA and PIF in all countries. The highest standardised CFA mortality rate occurred in England and Wales, and the lowest in Germany. Since 1979 mortality from CFA has increased in England and Wales, Australia, Scotland and Canada, but there was no trend in CFA mortality in New Zealand or Germany. In the USA mortality from CFA was low and has fallen. Mortality from PIF increased in all countries except New Zealand and Germany, and the highest PIF mortality, together with the greatest increase over time, was seen in the USA. Changes over time in the annual ratio of CFA to PIF deaths in all countries were small, implying that diagnostic transfer is not a major cause of the increasing CFA mortality. CONCLUSIONS: Mortality from CFA continues to increase in England and Wales and in many other countries. Diagnostic transfer from PIF does not appear to be a major cause of this. 相似文献