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1.
Replacement of the pyridinium ring of 6,11-ethanobenzo[b]quinolizinium cations with thiazolium (4a and 4b) and N-methylimidazolium (4c and 4d) resulted in equipotent compounds in the [3H]TCP binding assay. The corresponding N-methyl-1,2,4-triazolium analogs were less potent in this assay. The thiazolium derivative 4b, with a Ki = 2.9 nM, is being evaluated as a possible neuroprotective N-methyl-D-aspartic acid (NMDA) antagonist.  相似文献   
2.
Tested the hypothesis that information about a goal and/or task, choice in setting a strategy to achieve a goal, and task complexity interact to influence goal acceptance, personal goals, and performance. A laboratory experiment with 96 college students working on a class-scheduling task was used to test the hypothesis. The task consisted of producing mock class schedules consisting of 5 nonredundant classes. The Ss were assigned to either high-information, choice manipulation, or task-complexity conditions. Ss were administered a questionnaire assessing goal acceptance, personal goals, and performance prior to and on completion of the task. Results of 3-way ANOVA conducted on measures of goal acceptance, personal goals, and performance supported the hypotheses that choice in goal-setting and the provision of information interact as do information and task complexity. A 2nd study conducted to generalize these findings also supported the hypotheses. In the 2nd study, 40 animal caregivers (average age 28 yrs) were participants in a replication of the laboratory experiment with task complexity as a repeated-measures factor. Findings are discussed as a means of expanding the position of participation within the goal-setting model. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Examined how different sources (information given by a supervisor vs a shop steward) and types of information (work strategy vs work rationale) influence goal setting and performance in the US and England. It was hypothesized that workers receiving information from their shop stewards would outperform those receiving information from their supervisors. It was also hypothesized that workers receiving a job rationale would not as effectively perform or have as high a level of goal acceptance as workers who were provided task training. To test these hypotheses, 2 field experiments were conducted at comparable tire-production factories, with 60 18–53 yr old male workers participating from each country. Results demonstrate that the goal-setting method worked in England as it did in the US, except that a supervisor was not as effective a source of information as a shop steward in England. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
We report on the occurrence of coronal craniosynostosis, anal anomalies, and porokeratosis in two male sibs. A third male sib was phenotypically normal as were the parents. The occurrence of these three clinical features has, to our knowledge, not been reported before. Cutaneous or anal anomalies or both have been reported in a number of syndromes associated with craniosynostosis, including Crouzon, Pfeiffer, Apert, and Beare-Stevenson syndromes. These syndromes are associated with mutations in the fibroblast growth factor receptor genes FGFR1, FGFR2, and FGFR3. They are inherited in an autosomal dominant fashion. In contrast, the cases we report do not carry any of the common FGFR mutations and the pedigree suggests autosomal or X linked recessive inheritance.  相似文献   
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1. Peritubular capillary microperfusion was used to examine the effects of protein-free and hyperoncotic homologous plasma on fluid reabsorption by proximal convoluted tubules in the hydropenic rat. 3H-labelled p-aminohippurate was added to perfusates for the purpose of estimating the extent to which tubules under study were bathed by the perfusates. [14C]Mannitol was added to perfusates in order to detect contamination of collected tubular fluid by perfusates. 2. Hydrostatic pressures were monitored in the peritubular microvasculature and adjacent proximal tubules during perfusion. Evidence for secretion of p-aminohippurate from perfusate into tubules under study was determined by collecting tubular fluid from both early and late puncture site. Fractional and absolute reabsorption were not affected by either the protein-free or the hyperoncotic plasma. 3. When acetazolamide was added to the perfusate both fractional and absolute reabsorptive rates decreased by an average of 36%, indicating that the techniques were capable of detecting a decrease in proximal tubular reabsorption. 4. It is concluded that under the conditions of this study changes in peritubular capillary protein concentrations have no detectable effect on the rate of proximal convoluted tubule fluid reabsorption.  相似文献   
8.
Studied the effects of preexposure and gonadal hormone manipulation on the extinction of a conditioned taste aversion in 198 male Sprague-Dawley rats. In Exp I, Ss were given 1 prior exposure to sucrose at some selected time (Days 4, 2, or 1) before a 2nd exposure (Day 0) to sucrose and a LiCl injection, or they were given only a single exposure (Day 0). Under single exposure, castrated Ss extinguished the aversion faster than either testosterone-treated castrated Ss or sham-operated Ss. In Exp II, estradiol, dihydrotestosterone, and testosterone were studied by using only a Day 1 preexposure condition. The testosterone-treated group maintained the aversion for the longest period, followed by dihydrotestosterone-treated, sham, castrated, and estradiol-treated groups. In Exp III, estradiol was administered alone or in combination with 2 doses of dihydrotestosterone. Findings indicate that the outcome of behavior was dependent on the ratio of estradiol to dihydrotestosterone, with variations in this ratio resulting in fast (estrogen effect) to slow (androgen effect) rates of extinction. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Ruminant livestock, particularly cattle, is considered the primary reservoir of Escherichia coli O157:H7. This study examines the transmission of E. coli O157:H7 within groups of cattle during winter housing. Holstein Friesian steers were grouped in six pens of five animals. An animal inoculated with and proven to be shedding a marked strain of E. coli O157: H7 was introduced into each pen. Fecal (rectal swabs) and hide samples (900 cm2 from the right rump) were taken from the 36 animals throughout the study. Water, feed, and gate or partition samples from each pen were also examined. Within 24 h of introducing the inoculated animals into the pens, samples collected from the drinking water, pen barriers, and animal hides were positive for the pathogen. Within 48 h, the hides of 20 (66%) of 30 cohort animals from the six pens were contaminated with E. coli O157:H7. The first positive fecal samples from the noninoculated cohort animals were detected 3 days after the introduction of the inoculated steers. During the 23 days of the study, 15 of 30 cohort animals shed the marked E. coli O157:H7 strain in their feces on at least one occasion. Animal behavior in the pens was monitored during a 12-h period using closed circuit television cameras. The camera footage showed an average of 13 instances of animal grooming in each pen per hour. The study suggests that transmission of E. coli O157:H7 between animals may occur following ingestion of the pathogen at low levels and that animal hide may be an important source of transmission.  相似文献   
10.
The objectives of this study were to investigate colostrum feeding practices and colostrum quality on commercial grassland-based dairy farms, and to identify factors associated with colostrum quality that could help inform the development of colostrum management protocols. Over 1 yr, background information associated with dairy calvings and colostrum management practices were recorded on 21 commercial dairy farms. Colostrum samples (n = 1,239) were analyzed for fat, protein, lactose, and IgG concentration. A subset was analyzed for somatic cell count and total viable bacteria count. Factors associated with nutritional and IgG concentrations were determined using both univariate and multivariate models. This study found that 51% of calves were administered their first feed of colostrum via esophageal tube, and the majority of calves (80%) were fed >2 L of colostrum at their first feed (mean = 2.9 L, SD = 0.79), at a mean time of 3.2 h (SD 4.36) after birth, but this ranged across farms. The mean colostral fat, protein, and lactose percentages and IgG concentrations were 6.4%, 14%, 2.7%, and 55 mg/mL, respectively. The mean somatic cell count and total viable count were 6.3 log10 and 6.1 log10, respectively. Overall, 44% of colostrum samples contained <50 mg/mL IgG, and almost 81% were in excess of industry guidelines (<100,000 cfu/mL) for bacterial contamination. In the multivariate model, IgG concentration was associated with parity and time from parturition to colostrum collection. The nutritional properties of colostrum were associated with parity, prepartum vaccination, season of calving, and dry cow nutrition. The large variation in colostrum quality found in the current study highlights the importance of routine colostrum testing, and now that factors associated with lower-quality colostrum on grassland-based dairy farms have been identified, producers and advisers are better informed and able to develop risk-based colostrum management protocols.  相似文献   
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