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41.
EM Prvulovich JB Bomanji WA Waddington P Rudrasingham AM Verbruggen PJ Ell 《Canadian Metallurgical Quarterly》1997,38(5):809-814
1. Effects of feeding condition from birth were examined on the sensitivity of neuromuscular transmission to d-tubocurarine (dTc) in vitro in male mice of the ddY strain. 2. Mice were trained to climb two separated cylindrical steel-wire tubes for feeding and drinking, respectively, from 16 days of age. Some mice were conventionally fed, from 99 days of age. Nerve-muscle preparations were made from the left phrenic nerve diaphragm muscle (DPH), the sciatic nerve soleus muscle (SOL), and the sciatic nerve extensor digitorum longus muscle (EDL) of 99-day-old and 155-day-old mice. The nerve trunk was electrically activated with trains of four pulses and tetanic pulses. 3. The sensitivity to the effects of dTc decreased in the order EDL, SOL, and DPH. This result held true in all mice tested. 4. This sensitivity was significantly potentiated by the compulsory movement. 5. The supersensitivity remained even when mice were conventionally fed after 99 days of age. 6. The compulsion rendered EDL antifatigable on tetanic stimulation. This property was also retained after a return to conventional feeding. 7. These results suggest that the effects of feeding condition from birth might remain on neuromuscular functions after termination of the conditioning. 相似文献
42.
AM Molesworth 《Canadian Metallurgical Quarterly》1997,7(6):R77-R82
Health districts in England, Wales, and Northern Ireland were surveyed in 1996 to collect summary information about people with diagnosed HIV infection who received care under the statutory services in 1995. The survey provided demographic and epidemiological information about the prevalent caseload by area of residence, and the extent to which patients with diagnosed HIV infection travelled to obtain care related to it. A total of 13362 people with diagnosed HIV infection were reported to be resident and treated in England, Wales, or Northern Ireland in 1995. Forty-four per cent of these were treated outside the health district where they lived, with regional specialist centres attracting patients from wider areas. At least 13% received care from more than one treatment centre. This national survey of prevalent diagnosed HIV infections provided public health specialists with information relevant to their own localities without compromising confidentiality. This information complements surveillance data from confidential AIDS case diagnosis reports, laboratory reports of HIV infections, and the unlinked anonymous HIV prevalence monitoring programme, all of which contribute to the assessment and projection of demands on health and social services, and provide evidence on which to develop and direct national and local health campaigns. 相似文献
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MG Narducci L Virgilio JB Engiles AM Buchberg L Billips A Facchiano CM Croce G Russo JL Rothstein 《Canadian Metallurgical Quarterly》1997,15(8):919-926
In human leukemias and lymphomas nonrandom chromosomal rearrangements cause changes in cell growth and/or survival in such a way as to promote malignancy. The detailed study of the biochemical and genetic pathways altered in human cancer requires the identification or development of models to allow the study and manipulation of cancer gene function. Recently, the breakpoint gene TCL1, involved in chromosome translocations observed mostly in mature T-cell proliferations and chronic lymphocytic leukemias (CLL), was isolated and characterized, and showed to be part of a new gene family of proteins involved in these tumors. The murine Tcl1 gene, is similar in sequence to the murine and human MTCP1 gene also involved in T cell leukemias. The murine Tcl1 gene was shown to reside on mouse chromosome 12 in a region syntenic to human chromosome 14. Furthermore, we show that the murine Tcl1 gene is expressed early in mouse embryonic development and demonstrates expression in fetal hematopoietic organs as well as in immature T and B cells. Characterization of the murine Tcl1 gene will help in developing a mouse model of CLL and would provide the best opportunity to study and decipher the role of TCL1 in malignant transformation. 相似文献
45.
ID Zakharov AM Magasumov NI Simonova IaL E?del''man IuV Simenido 《Canadian Metallurgical Quarterly》1997,90(12):8-12
The authors present results of social and ecologic study carried out in Ufa. The results describe the course of ecologically important processes and phenomena in correlation with the public subjective understanding. Public health is influenced by hygienic parameters of food and water quality as well as a complex of social, economic and psychologic factors. Weak correlation between those parameters and ambient air pollution necessitates more accurate approach to ecologic mapping of cities and to manipulation with data on lower atmosphere pollution with chemical hazards. 相似文献
46.
B Decchi A Zalaffi R Spidalieri U Arrigucci AM Di Troia A Rossi 《Canadian Metallurgical Quarterly》1997,105(6):484-489
We describe here the results of a screening program conducted to discover inhibitors of the type-I interleukin-1 receptor (IL-1RI) from samples of microbial origin. An innovative approach, based on automated, nonradioactive receptor binding assays has been employed. Specially prepared cell-free systems have allowed the use of high concentrations of microbial metabolites in the reaction mixtures with a low percentage of false positives. More than 30,000 microbial samples from different species of soil isolates have been tested and two interesting activities have been purified and characterized. One of these, isolated from Streptomyces sp. GE48009, was identified as niphimycin, an antifungal agent also known as scopafungin. Preliminary evidence suggests that this molecule and azalomycin F, a structural analogue, inhibit IL-IRI by virtue of their long-chain guanidinium moiety. The other activity, isolated from Aspergillus sp. GE49752, was identified as flavipin, a substituted o-phthalaldehyde. 相似文献
47.
JR Naranjo B Mellstr?m AM Carrión JJ Lucas NS Foulkes P Sassone-Corsi 《Canadian Metallurgical Quarterly》1997,9(12):2778-2783
Thermal washout curves have been proposed as noninvasive tools for analysing lower airway dimensions and pulmonary blood flow, but how upper airway heat transfer affects these washout curves is unclear. The present study was designed to compare extrathoracic and tracheobronchial contributions to thermal washout curves. Respiratory frequency, air ambient temperature, and body core temperature (tc) were varied in six male subjects before and after immersion in cold (1.1 degrees C) water for up to 2 h under three conditions: 1) control: ambient temperature (tamb) = 25 degrees C, rectal temperature change (delta tre) = 0 degrees C; 2) pre-immersion: tamb = 4 degrees C, delta tre = 0 degrees C; and 3) post-immersion: tamb = 25 degrees C, delta tre = -0.7 degrees C. Both peak expiratory nasal (tpn) and oral (tpo) airstream temperatures were measured. Each subject was tested twice. Expiratory tpo was generally higher than tpn in all conditions. Increasing breathing rates lowered tpn and tpo in the control and cold air environments. Orifice temperatures, which are presumed to reflect upper airway blood temperatures, correlated with both tpn and tpo. Lowering tc had no effect on washout curves during quiet breathing and affected only tpn during rapid breathing. The results suggest that while tracheobronchial conditions may contribute to thermal washout curves, extrathoracic conditions predominate. Strong correlations between orifice temperatures, peak expiratory nasal temperatures and peak expiratory oral temperature demonstrate the dominant role of upper airway heat exchange in determining thermal washout curves. 相似文献
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Partial complementary DNA (cDNA) for thymidine phosphorylase (dThdPase) was cloned by means of a polymerase chain reaction. There was complete sequence identity between the amino acid sequence deduced from the nucleotide sequence of a clone (288 nucleotides) and the residues of platelet-derived endothelial cell growth factor (PD-ECGF). The amino acid sequence of all four peptide fragments from purified human dThdPase could be aligned with that of PD-ECGF. Our data indicate that residues 125-244 of PD-ECGF are identical to the sequence of human dThdPase. The molecular weights of human dThdPase and recombinant PD-ECGF (rPD-ECGF) that lacks 10 amino acids at the amino terminal were 55 and 52 kDa, respectively. Anti-PD-ECGF antibody recognized dThdPase, and anti-dThdPase antibody recognized rPD-ECGF. rPD-ECGF had dThdPase activity and its specific activity was similar to that of purified human dThdPase. dThdPase activity and molecules were detected in COS cells transfected with human PD-ECGF cDNA, but not in nontransfected cells. The sizes of PD-ECGF and dThdPase in the transfected COS cells were identical. These data suggest that human dThdPase is identical to PD-ECGF. 相似文献
50.
Hypothermia induced by surface cooling has shown to protect vulnerable regions of the brain during an ischemic insult. This study evaluated the neuroprotective efficacy of neurotensin, a potent hypothermic agent, using a 5-min carotid occlusion procedure in the gerbil. In Experiment 1, the dose-response and time course of neurotensin-induced hypothermia were evaluated (n = 5/dose). Central infusion of 10, 20, and 30 micrograms neurotensin were found to significantly decrease core body temperature of conscious gerbils within 30 min of administration. In Experiment 2, gerbils pretreated with 30 micrograms neurotensin were permitted to become hypothermic or were maintained at 37 degrees-38 degrees C (rectal) during ischemic insult. Other gerbils were pretreated with peptide vehicle prior to ischemic insult (at 37 degrees -38 degrees C) or underwent a sham procedure (n = 6/condition). At 24 h after surgery, gerbils were tested for increased locomotor activity in an open-field apparatus. Gerbils pretreated with peptide vehicle or neurotensin and maintained at 37 degrees-38 degrees C during ischemia had significantly higher activity levels compared to the other treated groups. In contrast, gerbils made hypothermic with neurotensin exhibited activity levels similar to sham gerbils. Histological assessment revealed that neurotensin-induced hypothermia protected the CA1 region from ischemic damage. 相似文献