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Retained placenta (RP), defined as fetal membranes not being expelled within 24 h after calving, is a costly disease in multiparous dairy cows that has been linked to immune suppression, infections, elevated lipid mobilization, and depleted status of antioxidants including α-tocopherol, and that increases the risk of other diseases (OD) in early lactation. Early detection of cows at increased risk of developing RP, OD, or both in early lactation could improve treatment success and result in improved milk production and reproductive performance. To identify risk indicators of RP, OD, or both, we used a nested case-control design and compared multiparous dairy cows that developed RP (n = 32) with cows that remained healthy (H; n = 32) or cows that developed OD (n = 32) in early lactation. We compared peripartal body condition score (BCS) as well as serum concentrations of α-tocopherol, metabolites [β-hydroxybutyrate (BHBA), cholesterol, glucose, nonesterified fatty acids (NEFA), and urea N], haptoglobin, and macrominerals (i.e., calcium, magnesium, and phosphorus) on d −21, −14, −7, −3, −1, 0, 1, 3, 7, 14, 21, 28, 35, 42, and 49 postpartum. In addition, average serum concentrations were calculated for each cow for the last 3 wk prepartum, for 3 and 2 wk prepartum combined, for the last week prepartum, and for the morning after calving and compared between groups. The RP cows had lower BCS than the H or OD cows until 2 wk postpartum. During the prepartal periods, RP and OD cows had lower α-tocopherol concentrations (corrected or not for cholesterol concentration) and higher NEFA and BHBA concentrations than H cows. Thus, lower prepartal BCS could be an early predictor for RP risk, and lower α-tocopherol concentrations and higher NEFA and BHBA concentrations could be early predictors for disease.  相似文献   
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The impact of social and clinical factors on the choice of coping strategies of a sample of 236 relatives of patients with schizophrenia, living in five European countries, was explored using well-validated questionnaires. The adoption of problem-focused coping strategies was more frequent among young relatives and among relatives of younger patients, and was associated with higher levels of practical and emotional social support and of professional help. In contrast, emotion-focused strategies were more frequently adopted by relatives who had been living longer with the patient and who had poorer social support. It is suggested that supportive and educational interventions should be provided as early as possible to relatives of patients with schizophrenia, which, in addition to having a practical focus, should also have a social focus, aiming at extending the family's social network.  相似文献   
3.
Feeding 56 versus 0 g/d of Saccharomyces cerevisiae fermentation product (SCFP; Diamond V Original XP; Diamond V, Cedar Rapids, IA) can increase feed intake and milk production in transition dairy cows. To evaluate the effects of various dosages of SCFP, Holstein cows were given individually a supplement containing 0 (n = 14), 56 (n = 15), or 112 g (n = 13) of SCFP daily during morning lockup as a topdressing to their total mixed ration. The supplement consisted of 0, 56, or 112 g of SCFP mixed with 84 g of molasses and 168, 112, or 56 g of corn meal, respectively. Supplement feeding began 28 d before predicted calving date (no less than 14 d) and ended 28 d postpartum, and supplement intake was evaluated daily. Blood samples were collected at d −21, −14, −7, −3, −1, 0, 1, 3, 7, 14, 21, and 28 to measure serum concentrations of macrominerals, metabolites, acute-phase proteins, immunoglobulin, and hormones. Milk weights were measured and milk samples were collected 2 times/wk on nonconsecutive days and analyzed for milk fat, protein, lactose, and somatic cell count (SCC). During the first day after calving, feeding SCFP versus no SCFP decreased serum cortisol concentrations and at least tended to increase supplement intake and serum concentrations of calcium, glucose, urea N, and serum amyloid A. During the first 4 wk postpartum, feeding SCFP versus no SCFP decreased milk SCC and increased milk production and serum phosphorus concentrations. Feeding 112 versus 56 g of SCFP/d did not show additional effects. Feeding SCFP may have a dosage-independent beneficial effect in supporting the physiologic adaptations after parturition, resulting in higher milk production and lower milk SCC  相似文献   
4.
We describe two experiments that examine 3D pathway displays in a head-up location for aircraft landing and taxi. We address both guidance performance and pilot strategies in dividing, focusing, and allocating attention between flight path information and event monitoring. In Experiment 1 the 3D pathway head-up display (HUD) was compared with a conventional 2D HUD. The former was found to produce better guidance, with few costs to event detection. Some evidence was provided that attentional tunneling of the pathway HUD inhibits the detection of unexpected traffic events. In Experiment 2, the pathway display was compared in a head-up versus a head-down location. Excellent guidance was achieved in both locations. A slight HUD cost for vertical tracking in the air was offset by a HUD benefit for event detection and for lateral tracking during taxi (i.e., on the ground). The results of both experiments are interpreted within the framework of object- and space-based theories of visual attention and point to the conclusion that pathway HUDs combine the independent advantages of pathways and HUDs, particularly during ground operations. Actual or potential applications include understanding the costs and benefits of positioning a 3D pathway display in a head-up location.  相似文献   
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We examined the dynamics of removal from circulation, tissue distribution, and persistence of phosphorothioate oligodeoxynucleotides (S-ODN) anti-tumor-necrosis-factor and a control of random sequence (randomer) in mice. After intravenous injection, the majority (96%) of S-ODN cleared rapidly from the circulation in the first two phases. In the first phase, 37.8 +/- 2.3% of the radioactivity had a mean half-life (t1/2) of 2.0 +/- 0.4 minutes. In the second phase, 58.1 +/- 1.5% of the radioactivity cleared with t1/2 of 12.6 +/- 0.2 minutes. The catabolic phase, constituting a minor proportion (4.1 +/- 0.8% of the total radioactivity), had a mean t1/2 of 2.7 +/- 0.5 hours. At a low dose (1 microgram) tissue distribution of both S-ODN anti-tumor-necrosis-factor and randomer were similar. The liver and kidneys were the major organs involved in uptake and removal of S-ODN. Autoradiographic studies showed the liver Kupffer cells to be the major site of uptake and renal urinary space for elimination. The clearance rate from the circulation was increased with the dose of S-ODN. In contrast, the fraction of radioactivity localized in the kidneys, liver, and spleen was decreased with increase in dosage. Furthermore, at a high dose (200 micrograms), the tissue distribution of the S-ODN anti-tumor-necrosis-factor differed significantly from the randomer. These findings have general significance in showing that the liver and kidneys are the major organs for removal of S-ODN and these organs are saturable at high doses. In addition, the results have specific importance in defining different parameters, dose and base composition, that affect utilization of antisense oligonucleotides for controlling gene expression in vivo.  相似文献   
7.
BACKGROUND: There is evidence that tissue factor (TF) is a major contributor to the thrombogenicity of a ruptured atherosclerotic plaque. Nitric oxide (NO) has antiatherogenic and antithrombotic properties. We investigated whether L-arginine (L-arg), the endogenous precursor of NO, might affect the ability of monocytes to produce TF. METHODS AND RESULTS: We studied TF expression in 18 rabbits with atherosclerosis induced by bilateral iliac damage and 10 weeks of a 2% cholesterol diet. Six weeks after the initiation of the diet, an angioplasty was performed. After angioplasty, the surviving rabbits (n=15) were randomized to receive L-arg (2.25%) supplementation in drinking water (L-arg group, n=8) or no treatment (untreated group, n=7). TF expression was evaluated in mononuclear cells from arterial blood in the presence and absence of endotoxin stimulation. Monocyte TF expression, as assessed with an amidolytic assay, did not differ significantly before or after the induction of atherosclerotic lesions (87+/-15 versus 70+/-12 mU of TF/1000 monocytes, P=NS). Endotoxin-stimulated TF activity increased significantly 4 weeks after angioplasty (138+/-22 versus 70+/-12 mU of TF/1000 monocytes, P=0.02). This increase was blunted by L-arg (43+/-16 mU of TF/1000 monocytes, P=0.01). CONCLUSIONS: This study demonstrates that angioplasty-induced plaque rupture is associated with a marked increase in monocyte TF response that is blunted by the oral administration of L-arg. This suggests that the documented antithrombotic properties of NO may be related in part to an inhibitory effect on monocyte TF response.  相似文献   
8.
Graber  G.F. Fadden  E.J. 《Computer》1976,9(7):55-62
In introducing the concept of an advanced hybrid computer system it is appropriate to describe briefly the current-generation hybrid system from which the advance is being made. The true significance of the advanced system can then be appreciated–namely that it retains all the advantages and at the same time removes the short-comings of the present generation of hybrid computers.  相似文献   
9.
The authors outline how the advantages of improved navigational accuracy can benefit both the individual aircraft and the air transportation system despite a mixed environment. The development of advanced navigation, flight planning, performance optimization, automatic guidance, and other capabilities in current and future flight management systems, together with the availability of digital communications between the airplane and ATC, suggests the need to review the potential airplane contributions to the ATC system of the future. A number of application areas utilizing current airborne flight management technology have been proposed for use with ATC that could provide significant operational benefits. These include: time-navigation applications in traffic management; multisensor navigation to provide automatic dependent surveillance; improved precision for approach, missed approach, and departure procedures; and improved navigational accuracy supporting reduced airway widths, holding pattern airspace, and aircraft separation standards. Several examples of operational benefits for operators and ATC during the transition period are identified, and the need for integrating these features into future ATC capabilities and procedures is stressed  相似文献   
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