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11.
J Gurevitch B Sela A Jonas H Golan Y Yahav JH Passwell 《Canadian Metallurgical Quarterly》1993,82(1):119-121
Isolation of Salmonella from the feces of impounded dogs was carried out to make clear the recent microbiological condition of dogs introduced into our facilities. Salmonella was isolated from 10 out of 283 samples (3.5%). Inparticular, during the first week after introduction, Salmonella was isolated from nine out of 74 dogs (12.2%). The isolation rate during the first week after introduction was significantly higher than that for dogs introduced later. No isolates were detected from dogs reared for more than 3 weeks after introduction. This study indicates that impounded dogs had the highest risk of infecting a person with Salmonella during the first week after introduction into our laboratory animal facilities, and that we need to pay attention to this fact when handling them. 相似文献
12.
RB Petersen H Goren M Cohen SL Richardson N Tresser A Lynn M Gali M Estes P Gambetti 《Canadian Metallurgical Quarterly》1997,41(3):307-313
NaCl-tolerant lactic acid bacteria (LAB) strains LC-10 (Lactobacillus casei) and LP-15 (Lact. plantarum) and NaCl were used as additives to sorghun (Sorghum bicolor). Numbers of LAB were significantly (P < 0.05) higher in all the additive-treated silages than in the control silage at an early stage of ensiling. During the fermentation process, addition of NaCl or LAB effectively inhibited the growth of aerobic bacteria and clostridia, but not yeasts. All the additive-treated silages had significantly (P < 0.05) lower pH, ammonia nitrogen content, dry matter loss and gas production but significantly (P < 0.05) higher lactic acid content and residual water soluble carbohydrates compared with the control silage. The improvement in silage quality was in the order: LAB > NaCl > control. Yeast counts were high in all additive-based silages and they increased during the exposure of the silages to air. As a result, these silages suffered aerobic deterioration, whereas the control silage was stable. The results confirmed that the NaCl or LAB improved fermentation quality but did not prevent aerobic deterioration of the silage. 相似文献
13.
14.
T. M. Maccagno S. Yue J. J. Jonas K. Dyck 《Metallurgical and Materials Transactions A》1993,24(7):1589-1596
An investigation was carried out on the effects of changing the hot-working, cold-working, and annealing parameters on the
interaction between A1N precipitation and recrystallization in low- carbon steels containing significant amounts of Al and
N. The primary aim was to determine whether laboratory torsion testing can be helpful in analyzing precipitation behavior
in these steels. The approach taken was first to establish the baseline annealing behavior of material that was hot- and cold-worked
in a mill and then to compare this with the behavior of material in which the hot and cold working were simulated by torsion
testing. It was found, first of all, that torsion testing can indeed provide a good simulation of the industrial process of
hot and cold working followed by annealing, even to the extent that a process as subtle as the inhibition of recrystallization
by A1N precipitation can be accurately reproduced. The results also show that the interaction between precipitation and recrystallization
during annealing is significantly influenced by the reheat temperature before hot working, as well as by the cooling rate
after hot working. 相似文献
15.
To investigate the outcome of Graves' thyrotoxicosis after antithyroid drug management, data from 81 patients, treated in Chang Gung Memorial Hospital at Taipei and Linkou from October 1981 to March 1990, were analyzed. The gender ratio of female to male was 59:22. The mean age of onset was 33.1 +/- 10.5(15-60) year-old. All the patients were treated with antithyroid drug (Thionamide group) for a duration of 11 to 63 months (mean +/- SD = 28.1 +/- 9.8 months). Forty of 81 patients (49.4%) were remained remission after up to 2 years of follow-up. Those patients relapse usually occurred within 2 years after discontinuation of treatment (34/41), and only one exceptional case relapsed after 3 years. Three conditions affected the relapse rate. Patients with larger goiter (grade II-III) and shorter duration of treatment (< 23 months) had a higher relapse rate than those-with smaller goiter (grade O-I) [29/46 vs. 12/35; chi 2 = 6.576, p = 0.010; p = 0.015 in stepwise logistic regression (LR)] and longer duration of treatment (> or = 23 months) (15/20 vs. 26/61; chi 2 = 6.316, p = 0.012; p = 0.020 in LR). Patients with higher pre-treated serum triiodothyronine (T3) level (T3 > or = 300 ng/dl) had a higher relapse rate than those with lower T3 level (T3 < 300 ng/dl) in univariate analysis (30/50 vs. 11/31, chi 2 = 4.601, p = 0.032), but no significant difference by LR (P = 0.094). Other clinical parameters including age, sex, past history, family history, thyroxine (T4) level, T3/T4 ratio, thyroid autoantibodies, staging of ophthalmopathy, responsiveness to thyrotropin-releasing hormone stimulation test at the end of treatment, and whether combined treatment with thyroxine had no significant difference between the relapse and remission groups. These data suggest: (a) patients with larger goiter (grade II-III had higher relapse rate; (b) most of the recurrent thyrotoxicosis patients relapsed within two years after drug withdrawal; (c) continuing treatment for more than twenty-three months produces better outcome; (d) patients with Graves' thyrotoxicosis should be followed up for at least three years after withdrawal of antithyroid drug. 相似文献
16.
Response to selection for milk yield in Holsteins was examined by a controlled selection experiment initiated in 1964. Foundation cows were paired by sire and divided randomly into two breeding groups, selection and control. Selection group was mated to four sires each year highest for Predicted Difference milk. Twenty bulls selected in 1964 as near breed average for milk sired all control cows. Milk yield was recorded for each lactation, and height of udder from ground, distances between teats, and perimeter and area bound by the four teats were measured at 30 to 75 days postpartum on 153 selection and 202 control cows over 14 yr. Most estimates of repeatability and heritability of udder dimensions before and after milking were .45 or larger. Correlations with milk yield were negative for udder height and positive for other udder measurements. Selection cows exceeded controls for lactational milk yield. Daughters of high milk bulls had greater distances between teats, greater perimeters, and larger areas of udder floor. Selection cows did not differ from controls in udder height for first parity but were below controls in udder height and had udders that collapsed more for all parities. 相似文献
17.
The outcome of treatment for bilateral congenital cataracts was studied retrospectively in a group of 51 patients. Two major categories of lens opacities were identified. In the first category, the opacities were extensive and visual impairment was evident early in the first year. These cataracts often occurred in eyes with small corneal diameters and poorly dilating pupils. Postoperative strabismus was nearly universal; nystagmus developed in over 50%; and late onset open-angle glaucoma developed in 8 of the 29 patients studied. Early surgery did not seem to abort the development of nystagmus in this group of patients. In the second category, the lens opacities were partial, often lamellar in configuration, and visual impairment was less severe. Surgery was usually performed after 3 years of age, with good visual results if the opacities were symmetrical and there was no nystagmus. No deprivation amblyopia developed in this group, even when surgery was delayed into the second decade. Strabismus developed postoperatively in about a third, but so far, no delayed open-angle glaucoma has been identified. 相似文献
18.
F Petersen H Z?hner JW Metzger S Freund RP Hummel 《Canadian Metallurgical Quarterly》1993,46(7):1126-1138
During germination spores of Streptomyces viridochromogenes NRRL B-1551 excrete a compound, germicidin, which has an inhibitory effect on the germination of its own arthrospores at a concentration as low as 200 pM (40 pg/ml). At higher concentrations germicidin inhibits porcine Na+/K(+)-activated ATPase and retards the germination of the cress Lepidium sativum. Germicidin is the first known autoregulative inhibitor of spore germination in the genus Streptomyces and was isolated from the supernatant of germinated spores, but also from the supernatant of the submerged culture. Spectroscopic analysis and derivatization reactions revealed germicidin to be 6-(2-butyl)-3-ethyl-4-hydroxy-2-pyrone (C11H16O3). Crude isolates of germicidin from the supernatant of submerged culture, but not from the spores, contained a second, structurally very similar compound (C10H14O3), in which in contrast to germicidin a 2-propyl instead of the 2-butyl chain was bound to C-6 and which did not show any activity in the germination and ATPase assay. The germination assay was evaluated as a new screening model for specifically active compounds. 相似文献
19.
P. R. Cetlin S. Yue J. J. Jonas T. M. Maccagno 《Metallurgical and Materials Transactions A》1993,24(7):1543-1553
Most laboratory simulations of hot rolling involve a scaling down of the strain rate from the much higher industrial levels.
This leads to slower softening between each rolling pass, for which corrections must be made. In the present work, torsion
testing simulations of “warm” rod rolling were conducted on a Ti-Nb interstitial-free (IF) steel at 840 °C and 770 °C(i.e., in the ferrite range). For this purpose, “strain rate corrected” interpass times were used, in addition to the more familiar
corrections for the stress. The results are compared with those obtained from simulations using uncorrected industrial interpass
times. At 840 °C, simulations using corrected interpass times led to high levels of softening between the stages of rolling,
thus triggering the reinitiation of cycles of dynamic recrystallization. The initially high stress level at the start of these
cycles was responsible for the large differences in the pass-to-pass mean flow stress behavior, compared with that observed
when using uncorrected industrial interpass times, or continuous deformations. The differences were much less pronounced at
770 °C, where the rate of softening is much slower than at 840 °C. Predictions for softening based on the Avrami equation
underestimated the softening observed using the continuous and uncorrected industrial interpass time schedules and overestimated
it for the corrected ones. The former is due to the occurrence of recovery, which is not addressed by the Avrami relation,
while the latter is due to the precipitation that takes place during the corrected (longer) interpass times. It was also found
that simulations using continuous deformations are applicable only if the interpass softening that would be expected using
the corrected interpass times does not exceed about 20 pct. 相似文献
20.
J Holst B Lindblad D Bergqvist O Nordfang PB Ostergaard JG Petersen G Nielsen U Hedner 《Canadian Metallurgical Quarterly》1994,71(2):214-219
The aim was to investigate whether a truncated recombinant Tissue Factor Pathway Inhibitor (TFPI1-161), which lacked the third Kunitz-type domain and the basic c-terminal region, had an antithrombotic effect comparable to LMWH in a randomised double-dummy study. The experimental thrombosis was induced in jugular veins, in a total of 40 rabbits by a combination of destruction of the endothelium and restricted blood flow. Group 1: placebo, gr 2: LMWH 60 anti-FXa IU/kg, gr 3-5: 0.1, 1.0 and 10.0 mg/kg TFPI1-161. TFPI1-161 reduced the thrombus weights in all treated groups, significantly in doses of 1.0 and 10.0 mg/kg compared to placebo. The frequency of thrombosis and occlusive thrombosis were also significantly reduced in those doses. The antithrombotic properties of TFPI1-161 (1.0-10.0 mg/kg) measured as thrombus weight, frequency of thrombosis and frequency of occlusive thrombosis was equivalent to the anti-thrombotic properties of LMWH. In the anti-FXa, APTT and PT-assays TFPI1-161 displayed a dose dependent increase of activity. Recombinant-TFPI1-161 did not influence the anti-FIIa-assay. No haemorrhagic side effects were noted. 相似文献