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31.
Evidence is accumulating that indoor dampness and mold are associated with the development of asthma. The underlying mechanisms remain unknown. New Zealand has high rates of both asthma and indoor mold and is ideally placed to investigate this. We conducted an incident case‐control study involving 150 children with new‐onset wheeze, aged between 1 and 7 years, each matched to two control children with no history of wheezing. Each participant's home was assessed for moisture damage, condensation, and mold growth by researchers, an independent building assessor and parents. Repeated measures of temperature and humidity were made, and electrostatic dust cloths were used to collect airborne microbes. Cloths were analyzed using qPCR. Children were skin prick tested for aeroallergens to establish atopy. Strong positive associations were found between observations of visible mold and new‐onset wheezing in children (adjusted odds ratios ranged between 1.30 and 3.56; P ≤ .05). Visible mold and mold odor were consistently associated with new‐onset wheezing in a dose‐dependent manner. Measurements of qPCR microbial levels, temperature, and humidity were not associated with new‐onset wheezing. The association between mold and new‐onset wheeze was not modified by atopic status, suggesting a non‐allergic association.  相似文献   
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This study assesses the long-term (mean 52+/-24 months) performance of the St. Jude Medical (SJM) valve in 200 young (mean age 31+/-13 years) rheumatic patients on low-level warfarin anticoagulation combined with dipyridamole. Follow-up was 95% complete and comprised 867 patient-years. There were 33 deaths (3.8%/patient-year). Death was valve related in 12 cases and due to left ventricular dysfunction in 10. Death due to left ventricular dysfunction occurred earlier after surgery than death due to other causes (10+/-7 vs 29+/-18 months, p <0.005); these patients had larger preoperative left ventricular dimensions than the rest of the group (end-systolic diameter 51+/-13 vs 37+/-16 mm, end-diastolic diameter 66+/-13 vs 50+/-19 mm, p = 0.006). Actuarial probability of survival was 81% at 86 months and probability of event-free survival was 71%. The median international normalized ratio was 1.88+/-0.54. Thromboembolism (13 events) occurred at a linearized rate of 1.5%/patient-year. There were 11 major bleeding episodes (1.3%/patient-year), 4 cases of prosthetic valve endocarditis (0.8%/patient-year), and 12 paraprosthetic leaks (1.4%/patient-year). No valve obstructions or reoperations occurred. Thus, the SJM valve performs well on low-level anticoagulation combined with dipyridamole. Left ventricular dysfunction was a common cause of death in the early postoperative period.  相似文献   
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Naphthenic acids (NAs) are complex mixtures of naturally occurring acyclic and cyclic aliphatic carboxylic acids that are responsible for the toxicity of the water in the tailings ponds associated with the recovery of bitumen from the Athabasca oil sands. NAs are difficult to analyze due to their complexity and the lack of commercially available NA standards. This paper describes the use of negative ion electrospray ionization mass spectrometry for the analysis of NAs. Model carboxylic acids, alone and in mixture, afforded mass spectral signal intensities that were highly dependent on extractor and cone voltages and on molecular structure. These effects were also observed for authentic NAs. Under conditions that were close to optimal for all the model compounds, their calibration sensitivities varied by a factor of <2, and there were minimal interactions when the model compounds were examined in mixture. Under the same conditions, the authentic NAs showed apparent congener distributions similar to those observed previously by GC/MS for derivatized NAs. The similar calibration sensitivities among congeners allowed the use of the standard addition method to determine the approximate absolute concentrations of NA congeners in an authentic sample.  相似文献   
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Alginate as a source of dietary fiber   总被引:3,自引:0,他引:3  
Alginate, an algal polysaccharide, is widely used in the food industry as a stabilizer, or as a thickening or emulsifying agent. As an indigestible polysaccharide, alginate may also be viewed as a source of dietary fiber. Previous work has suggested that dietary fibres may protect against the onset and continuation of a number of cardiovascular and gastrointestinal diseases. This article aims to examine what is currently understood about the fiber-like activities of alginate, particularly its effects on intestinal absorption and the colon, and therefore aims to gauge the potential use of alginate as a dietary supplement for the maintenance of normal health, or the alleviation of certain cardiovascular or gastrointestinal diseases.  相似文献   
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Fungal membrane responses induced by plant defensins and thionins   总被引:1,自引:0,他引:1  
Treatment of hyphae of Neurospora crassa with antifungal plant defensins, i.e. Rs-AFP2 and Dm-AMP1 isolated from radish and dahlia seed, respectively, induced a rapid K+ efflux, Ca2+ uptake, and alkalinization of the incubation medium. The Rs-AFP2-induced alkalinization of the incubation medium could be inhibited with G-protein inhibitors. alpha-Hordothionin, an antifungal thionin from barley seed, caused a sustained increased Ca2+ uptake at subinhibitory concentrations but only a transient increased uptake at inhibitory concentrations. alpha-Hordothionin also caused increased K+ efflux and alkalinization of the medium, but these fluxes occurred more rapidly compared to those caused by plant defensins. Furthermore, alpha-hordothionin caused permeabilization of fungal hyphae to the non-metabolite alpha-aminoisobutyric acid and, in addition, altered the electrical properties of artificial lipid bilayers, consistently leading to rupture of the lipid bilayers. The plant defensins did not form ion-permeable pores in artificial membranes and did not exhibit substantial hyphal membrane permeabilization activity. Our results are consistent with the notion that thionins inhibit fungal growth as a result of direct protein-membrane interactions, whereas plant defensins might act via a different, possibly receptor-mediated, mechanism.  相似文献   
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The concurrent and predictive validity of the Psychopathy Checklist: Youth Version (PCL:YV) were examined across gender and ethnicity using multiple outcome measures on a community-based sample of 130 adjudicated youths. The PCL:YV demonstrated concurrent validity with externalizing behavior problems but, it is important to note, was also associated with internalizing measures of negative affect. With a mean follow-up period of 3 years, the PCL:YV was found to predict general and violent recidivism in male, Native Canadian, and Caucasian youths. However, the PCL:YV demonstrated weaker concurrent and predictive validity with girls and failed to predict nonviolent recidivism in all subgroups. Implications of the findings for clinical practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Site-specific mutagenesis studies of the first epidermal growthfactor-like (EGF-like) domain of human clotting factor IX suggestthat the calcium-binding site present in this domain (dissociationconstant Kd=1.8 mM at pH 7.5 and ionic strength I=0.15) involvedthe carboxylate residues Asp47, Asp49 and Asp64. To furthercharacterize the ligands required for calcium binding to EGF-likedomains, two new mutations, Asp47 - Asn and Asp49 - Asn, wereintroduced into the domain by peptide synthesis. 1H-NMR spectroscopywas used to obtain the dissociation constants for calcium bindingto these mutations. Calcium binding to the Asp49- Asn modifieddomain is only mildly affected (Kd=6 mM, I=0.15), whereas bindingto the Asp47- Asn modified domain is severely reduced (Kd=42mM, I=0.15). From these data, it is proposed that the anionicoxygen atoms of the side chains of residues 47 and 64 are essentialfor calcium binding, whereas the side chain ligand for calciumat residue 49 can be a carboxyamide oxygen. As a control, theintroduction of the modification Glu78- Asp in a region of thedomain not believed to be involved in calcium binding had verylittle effect on the Kd for calcium (Kd=2.6 mM, I=0.15). Finally,the effect of an Asp47- Gly substitution found in the naturalhaemophilia B mutant, factor IXAlabama, was investigated. Thispeptide has a markedly reduced affinity for calcium (Kd=37 mM,I=0.15), suggesting that the defect in factor IXAlabama is dueto impaired calcium binding to its first EGF-like domain.  相似文献   
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