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1.
Transduction of MDR1 may be of use in chemoprotection of normal bone marrow (BM) cells during treatment of malignancies, or as a selectable marker for the transfer of other genes into the BM, a critical target for the cure of many diseases. To that aim, the human multidrug resistance gene MDR1 was cloned into an SV40 pseudoviral vector containing the SV40 origin of replication (ori) and encapsidation signal (ses), and the plasmid was encapsidated in COS cells as SV40/MDR1 pseudovirions. Expression of the human MDR1 gene was demonstrated in murine MEL cells infected with SV40/MDR1 pseudovirions, using a monoclonal antibody (MPK16) specific for the human 170-kD P-glycoprotein. Functional P-glycoprotein was demonstrated by resistance to colchicine in NIH-3T3 cells infected with SV40/MDR1 pseudovirions. Activity of P-glycoprotein was assayed by rhodamine-123 dye exclusion and fluorescence-activated cell sorter analysis (FACS) in various cell types including hematopoietic cells. Highly efficient gene transfer and expression was demonstrated in all murine and human cell types tested, including primary human BM cells. Using multiplicities of infection (moi) of 1-2, over 95% of cells were found to become MDR1+. The percent of MDR1+ cells was proportional to the moi. We conclude that the SV40 pseudoviral vector is efficient for gene transmission into human hematopoietic cells. 相似文献
2.
G Passarino P Burlo G Ciccone A Comino M Cravello P Iannicelli F Mollo 《Canadian Metallurgical Quarterly》1997,121(6):619-622
OBJECTIVE: To evaluate the prevalence of myocarditis in a general hospital in Turin, Italy. DESIGN: We retrospectively reviewed 17162 postmortem records from autopsies routinely performed at San Giovanni Battista General Hospital, Turin, between 1965 and 1994. RESULTS: Applying the so-called Dallas criteria, myocarditis was histologically found in 91 cases (0.53%, 95% CI 0.4 to 0.7). The prevalence increased, reaching a peak between 1985 and 1994 (1.2%, 95% CI 0.9 to 1.6). The disease was found more frequently in patients from 20 to 39 years of age, with no difference between males and females. The present data were compared to those of a previous study, performed in 1985 and 1993 to 1994, in which we had prospectively taken into account 605 autopsies (not comprised in the present retrospective study) with standardized myocardial sampling for histological examination: a 5.1% prevalence was found (nearly five times as high as that retrospectively detected in the same period). CONCLUSIONS: If a standardized method of myocardial samples for microscopic examination is not followed, it is possible that myocarditis is overlooked in an unsuspected number of cases. 相似文献
3.
AIM: To study the toxic effects of norfloxacin (Nor) on EEG and ultrastructure of the brain. METHODS: EEG was recorded in the sensorimotor area of rat cortex after Nor 150 and 300 micrograms.kg-1 were injected into the right ventricle of the brain. RESULTS: Spike waves occurred, first at the ipsilateral side and then bilaterally. The seizure spike appeared at 168 +/- 129, 51 +/- 35 s, and 276 +/- 138, 118 +/- 65 s in the right and left cerebral cortices in 150 and 300 micrograms.kg-1 groups, respectively. The wave forms were variable, the wave amplitude and frequency increased gradually, accompanied with limb twitching. Neuron degeneration was seen in both cerebral hemispheres, hippocampus, and cerebellum 120 min after the i.c.v. of Nor 300 micrograms.kg-1: myeloid degeneration of Golgi complex, rough endoplasmic reticulum, and neuropils; swelling of cytoplasm; dissolution of nuclears and chromatin; necrosis of gliocytes and the appearance of changes in both the light and dark neurons, especially the dark ones. CONCLUSION: Rat brain was widely damaged after the kindling by Nor. 相似文献
4.
NG Faith JA Shere R Brosch KW Arnold SE Ansay MS Lee JB Luchansky CW Kaspar 《Canadian Metallurgical Quarterly》1996,62(5):1519-1525
A survey was conducted between March and October of 1994 to determine the prevalence and identify the sources of serotype O157:H7 isolates of Escherichia coli in Wisconsin dairy herds. A stratified sample of 400 farms was identified, and 70 farms with weaned calves less than 4 months old were included in the study. During the prevalence study, 5 of the 70 farms (herd prevalence, 7.1 +/- 4.5%) and fecal samples from 10 of 560 calves (animal prevalence, 1.8%) tested positive for serotype O157:H7. In a follow-up study, the five O157:H7-positive farms and seven of the O157:H7-negative farms identified in the prevalence study were visited again. An additional 517 fecal samples from cattle of various ages were tested, and a total of 15 animals from four of the five herds that were previously positive and 4 animals from two of seven herds that were previously negative tested positive for E. coli O157:H7. Observations made during the follow-up study suggested that horizontal transmission was an important means of E. coli O157:H7 dissemination on the farms. A total of 302 environmental samples, were examined, and 2 animal drinking water samples from one previously negative farm and 1 animal drinking water sample from a previously positive farm contained E. coli O157:H7. Analyses by the pulsed-field gel electrophoresis technique of contour-clamped homogeneous electric field electrophoresis revealed that isolates from the same farm displayed identical or very similar XbaI restriction endonuclease digestion profiles (REDP), whereas isolates from different farms typically displayed different REDP. However, more than one REDP was usually observed for a given herd over the 8-month sampling period. Analyses of multiple isolates from an animal revealed that some animals harbored O157:H7 strains that had different REDP, although the REDP of isolates obtained from the same fecal sample were very similar. Collectively, 160 bovine isolates obtained from 29 different animals and three water isolates displayed 20 distinct XbaI REDP. Our data revealed that there are several clonal types of serotype O157:H7 isolates in Wisconsin and indicated that there is probably more than one source of this pathogen on the dairy farms studied. However, animal drinking water was identified as one source of E. coli O157:H7 on one farm. 相似文献
5.
Many patients with psychotic disorders lack awareness of being ill. This often presents a serious impediment to treatment compliance. We hypothesized that exposing partially remitted patients to videotapes of themselves, made while they were acutely psychotic, might increase their insight into the nature of their illness. Eighteen acutely psychotic inpatients were assigned randomly to a control or experimental group and interviewed on videotape 24 to 48 hours after admission, using scales that measure insight (Insight and Treatment Attitudes Questionnaire [ITAQ]) and psychopathology (Brief Psychiatric Rating Scale [BPRS]). One to six weeks later, when judged to be significantly improved, subjects were shown either a videotape of their initial interview (experimental group) or a placebo videotape (control group) and then reinterviewed 24 to 48 hours later on videotape, using the BPRS and ITAQ scales. Evaluation of initial and final ITAQ and BPRS scores revealed significantly greater improvement in insight scores and in delusionality in the experimental group. However, no significant difference in overall psychopathology was seen for the two groups. These results suggest that exposure of hospitalized patients to videotapes of their own psychotic behavior may be a cost-effective therapeutic tool for developing personal insight into psychotic illness. 相似文献
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The long-lived waste dumps of gold-extraction plants, by the amount of gold concentrated in them, are an alternative source of raw materials for the gold-mining enterprises. During the long-term storage of waste dumps, difficult-to-extract gold under the effect of environmental factors is being opened up and can be extracted using the cyanide process. It is established by investigations that the extraction of Au during percolation cyanidation attains 75–82%, and waste dumps can be used for their heap leaching. However, because of a low fineness of mineral formations, percolation of working solutions through the stack bulk and its retention from static destruction are complicated. The technology of pelletizing the waste dumps with the use of predrying with warm air or by mixing with the ore in definite proportions is suggested. To prevent washing out, the stack height should be smaller than that with the use of the ore, and its edges should be protected by natural coatings. Therefore, processing of waste dumps by heap leaching can turn out to be a promising practical direction. 相似文献
8.
JR Chambers JR Bisaillon Y Labbé C Poppe CF Langford 《Canadian Metallurgical Quarterly》1998,77(10):1497-1501
Swabs of crop contents of 635 broiler chickens were obtained from 9 Ontario and 12 Quebec processing plants and cultured for Salmonella to determine prevalence in broiler crops. Serotypes of positive cultures were determined to evaluate the serotype profile. The overall prevalence of contamination was low (4.3%). Prevalence was higher in broilers sampled in Quebec (5.8%) than in those sampled in Ontario (2.2%). In Quebec, there were differences in prevalence among the groups of broilers sampled at the various plants. These differences were believed to be attributable to differences in Salmonella prevalence among groups of flocks delivered to the plants due to the limited exposure of the chickens to the plant. The serotype profile of Salmonella isolated from the crops of broilers in this study was similar in several respects to profiles obtained from other surveys of Canadian broiler flocks using either environmental samples or cloacal swabs. Similarities included: predominance of Salmonella hadar and Salmonella heidelberg; several other common serotypes at a low prevalence; little Salmonella enteritidis isolated in other studies, and no S. enteritidis isolated in this study. Results of this field survey of Salmonella in crops of broilers are similar to those of Canadian studies of other internal and environmental sites of broilers. The similarity indicates that monitoring of Salmonella environments of flocks of live broiler chickens should define profiles of Salmonella contamination of the carcasses and would also aid in determination of Salmonella contamination status of broiler flocks. Such information would assist efforts to reduce Salmonella contamination in broiler chickens. 相似文献
9.
A Jalila P Dorny R Sani NB Salim J Vercruysse 《Canadian Metallurgical Quarterly》1998,74(2-4):165-172
Coccidial infections were studied in goats in the state of Selangor (peninsular Malaysia) during a 12-month period. The study included 10 smallholder farms on which kids were monitored for faecal oocyst counts from birth until 1-year old. Eimeria oocysts were found in 725 (89%) of 815 faecal samples examined. Nine species of Eimeria were identified. The most prevalent were E. arloingi, found in 71% of the samples, E. ninakohlyakimovae (67%), E. christenseni (63%) and E. alijevi (61%). The other species found were, E. hirci, E. jolchijevi, E. caprovina, E. caprina and E. pallida, present in 34, 22, 12, 9 and 4% of the samples, respectively. Oocyst counts were significantly higher in animals of less than 4-months old (P < 0.05). High oocyst counts were mainly caused by non-pathogenic species. Poor hygienic conditions were found to be associated with a higher intensity of coccidial infections. Mortality rates in kids could not be related to the intensity of coccidial infections. 相似文献
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Recent studies in molecular biology and gene engineering were conducive to accumulation of numerous facts which help better understand the processes of plant genome functioning and follow up the effects of recombination processes in purposefully modified genome of a transformed plant on its expression. This review analyzes the major approaches to studies and results attained in plant gene engineering and plant genome imprinting. 相似文献
11.
TM Brown KE Robbins M Sinniah TS Saraswathy V Lee LS Hooi B Vijayamalar CC Luo CY Ou J Rapier G Schochetman ML Kalish 《Canadian Metallurgical Quarterly》1996,12(17):1655-1657
Peripheral blood mononuclear cell specimens were collected from 13 HIV-1-infected IV drug users in Kuala Lumpur, Malaysia, as well as one HIV-infected baby, between 1992 and 1993. DNA was then amplified by nested polymerase chain reaction and a 345-bp fragment of the C2V3 region of the env gene was sequenced. 11 of the 14 Malaysian sequences clustered with the B' subtype, one different from the typical subtype B US strains HIVMN and HIVSF2. Two sequences grouped in the C subtype and had sister taxa closer to the Indian C subtype sequences than those from Zambia. The sequence from the infant was identified as a subtype E virus, grouped more closely with subtype E strains from Thailand than subtype E viruses from the Central African Republic. 相似文献
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In Salmonella typhimurium, precursors to the pyrimidine moiety of thiamine are synthesized de novo by the purine biosynthetic pathway or the alternative pyrimidine biosynthetic (APB) pathway. The apbA gene was the first locus defined as required for function of the APB pathway (D. M. Downs and L. Petersen, J. Bacteriol. 176:4858-4864, 1994). Recent work showed the ApbA protein catalyzes the NADPH-specific reduction of ketopantoic acid to pantoic acid. This activity had previously been associated with the pantothenate biosynthetic gene panE. Although previous reports placed panE at 87 min on the Escherichia coli chromosome, we show herein that apbA and panE are allelic and map to 10 min on both the S. typhimurium and E. coli chromosomes. Results presented here suggest that the role of ApbA in thiamine synthesis is indirect since in vivo labeling studies showed that pantoic acid, the product of the ApbA-catalyzed reaction, is not a direct precursor to thiamine via the APB pathway. 相似文献
14.
BACKGROUND: We evaluated routine transition zone biopsies for the detection of prostate cancer. METHODS: Systematic sextant transrectal biopsies, including 2 systematic transition zone biopsies (sextant biopsy group), were performed on 196 consecutive patients. Biopsies were based on indications from digital rectal examination and/or a serum PSA level greater than 4.0 ng/mL. During the same period, 21 patients with persistently elevated PSA levels and earlier negative systematic biopsies also had the sextant biopsy (re-biopsy group). The sextant biopsy group was compared with 124 cases in our previous cancer detection program who had systematic quadrant biopsies targeted to the peripheral zone (quadrant biopsy group). RESULTS: Between the sextant and quadrant biopsy groups, the difference in rate of cancer detection was not significant statistically. Of the sextant biopsy group, 64 (33%) demonstrated malignancy, including 9 (4.6%) with cancer found exclusively in the peripheral zone and 55 (28%) both in the peripheral and transition zones. No cancer was found exclusively in the transition zone. Of the re-biopsy group, all 4 cancers (19%) were detected in the transition zone, 2 of them exclusively in the transition zone. CONCLUSION: Routine transition zone biopsies did not increase the detection rate of prostate cancer. Systematic transition zone biopsies proved useful to the patients with persistently elevated PSA values and negative results in previous systematic peripheral zone biopsies. 相似文献
15.
A. V. Kuklev Yu. M. Aizin V. Ya. Genkin V. S. Lukovnikov G. S. Bobylev 《Metallurgist》1999,43(4):176-179
Foreign Practice
Continuous casting of steel at metallurgical plants in Poland 相似文献16.
S Wang WG Bottje D Cawthon C Evenson K Beers R McNew 《Canadian Metallurgical Quarterly》1998,77(10):1556-1564
This study was conducted to document the glutathione (GSH) cycle (interorgan circulation of GSH) in broilers in vivo. Two experiments were conducted on 36 anesthetized male broilers (n = 6 per treatment) implanted with cannulae in the carotid artery, hepatic portal, and hepatic veins. Plasma GSH, glutamate, cysteine, cystine, and cysteinylglycine levels in each vessel were monitored following a bolus injection [Experiment (Exp.) 1] or 30 min continuous infusion (Exp. 2) of GSH, or a gamma-glutamyltranspeptidase inhibitor (AT125) into the hepatic portal vein. Controls received saline alone. The GSH and AT125 treatments were used to determine the effect of increasing the prehepatic GSH load and of inhibiting systemic GSH degradation, respectively, on the GSH cycle. Hepatic export of GSH was clearly evident in all three treatment groups in both experiments (Exp.). The GSH and AT125 treatments raised amino acid levels in some or all of the vessels, whereas cysteinylglycine was elevated by AT125 and depressed by the GSH treatment compared to Controls. Hepatic uptake of glutamate, cysteine, and/or cystine was observed in Controls and GSH-treated birds, but not in birds given AT125 (Exp. 2). Neither hepatic export nor uptake of cysteinylglycine was observed in any treatment group. The results clearly demonstrate the ability of the avian liver to export GSH into the general circulation despite alterations that might arise from changes in extra-hepatic ability to utilize GSH or its constituent amino acids. 相似文献
17.
Shape and slant judgments of rotated or frontoparallel ellipses were elicited from three groups of 10 subjects. A masking stimulus was introduced to control processing time. Backward masking trials were presented with interstimulus intervals of 0,25 and 50 msec. Reduction of processing time altered shape judgments in the direction of projective shape and slant judgments in the direction of frontoparallelness. This finding is consistent with the shape-slant invariance hypothesis. In order to study the effects of processing load, one group of subjects was given prior knowledge of the kind of judgment to be made on each trial, one group had no prior knowledge, and a third group made both judgments on each trial. The effects of the processing load manipulation were interpreted in terms of the role of attention in perceptual encoding. Consistent with previous findings, allocation of attention did not affect perceptual encoding. 相似文献
18.
E Gregory H Barnhart DW Dreesen NJ Stern JL Corn 《Canadian Metallurgical Quarterly》1997,41(4):890-898
From October 1993 to August 1994, broiler chickens in four grow-out houses, two previously used (houses 1 and 2) and two newly constructed (houses 3 and 4), were used in a study to determine the source, time of infection, and prevalence of Campylobacter spp. Cecal droppings and cecal samples were obtained from the broilers. Samples were also obtained from water, feed, litter, soil, fans, and workers' boots. Samples were obtained from domestic animals and wildlife species (rectal swabs), including insects, on or near the premises. Broilers in houses 2, 3, and 4 became infected in the second or third week and were fully colonized by day 42. Campylobacter appeared in house 1 during week 2 in a low percentage of the birds, disappearing by the fourth week. Isolates were also recovered from domestic pigs and water on this farm. In house 3, the organism was isolated from workers' boots and a wild bird prior to isolation from the broilers. Following isolation from cecal droppings, the organism was isolated from water, feed, litter, feathers, flies, cattle, feces, and wild animals. In house 2, Campylobacter was isolated from cattle feces and wild birds prior to week 5, when the broilers first became infected, and thereafter from water, feed, insect, and wildlife, and cecal droppings. It was subsequently isolated from workers' boots, cattle feces, feathers, insects, and other wildlife. All ceca taken from 20 birds each from houses 2 and 3 were positive at time of slaughter (day 49). All ceca from house 1 were negative. No ceca were collected from birds originating in house 4. No specific source could be identified from the samples obtained, although apparently the organism permeates the environment and several potential sources are discussed in this paper. 相似文献
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Evans James D.; Good Susan M.; Lintzenich Patricia; Francis Nanette C. 《Canadian Metallurgical Quarterly》1975,29(4):327
Conducted 2 experiments, involving 45 high school and 60 college students, on the possibility that the effect of repetition on the long-term retention of common nouns depends upon the form of study being used. In Exp I, 3 levels of processing were combined factorially with 3 degrees of repetition in an incidental-learning task. Results indicate that semantic processing yields a larger repetition effect than "minimal" structural processing. Exp II, which entailed the factorial crossing of level of processing with type of processing, also showed that level of processing interacts with repetition to determine long-term retention. Type of processing, however, failed to have any effect. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献