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31.

Purpose

Light-emitting diode (LED) technology is increasingly being used for general lighting. Thus, it is timely to study the environmental impacts of LED products. No life cycle assessments (LCA) of recessed LED downlight luminaires exist in the literature, and only a few assessments of any type of LED light source (component, lamp and luminaire) are available.

Methods

The LCA of a recessed LED downlight luminaire was conducted by using the data from the luminaire manufacturer, laboratory measurements, industry experts and literature. The assessment was conducted using SimaPro LCA software. EcoInvent and European Reference Life Cycle Database were used as the databases. The LCA included a range of environmental impacts in order to obtain a broad overview. The functional unit of the LCA was one luminaire used for 50,000 h. In addition, the sensitivity of the environmental impacts to the life was studied by assessing the LED downlight luminaire of 36,000 h and 15,000 h useful life and to the used energy sources by calculating the environmental impacts using two average energy mixes: French and European.

Results and discussion

The environmental impacts of the LED luminaire were mostly dominated by the energy consumption of the use. However, manufacturing caused approximately 23 % of the environmental impacts, on average. The environmental impacts of manufacturing were mainly due to the driver, LED array and aluminium parts. The installation, transport and end of life had nearly no effect on the total life cycle impacts, except for the end of life in hazardous waste. The life cycle environmental impacts were found to be sensitive to the life of the luminaire. The change from the French to the European average energy mix in use resulted to an even clearer dominance of the use stage.

Conclusions

The case study showed that the environmental impacts of the LED downlight luminaire were dominated by the use-stage energy consumption, especially in the case of the European energy mix in use. Luminous efficacy is, thus, a relatively appropriate environmental indicator of the luminaire. As LED technology possesses generally higher luminous efficacy compared to conventional ones, the LED luminaire is considered to represent an environmentally friendly lighting technology. However, data gaps exist in the data in LED product manufacturing and its environmental impacts. The environmental impacts of different LED products need to be analysed in order to be able to precisely compare the LED technology to the conventional lighting technologies.  相似文献   
32.
Mycoplasmosis is a frequent causative microbial agent of community-acquired pneumonia and has been linked to exacerbation of chronic obstructive pulmonary disease. The macrophage class A scavenger receptor (SRA) facilitates the clearance of noxious particles, oxidants, and infectious organisms by alveolar macrophages. We examined wildtype and SRA−/− mice, housed in either individually ventilated or static filter-top cages that were cycled with fresh bedding every 14 d, as a model of gene–environment interaction on the outcome of pulmonary Mycoplasma pulmonis infection. Intracage NH3 gas measurements were recorded daily prior to infection. Mice were intranasally infected with 1 × 107 cfu M. pulmonis UAB CT and evaluated at 3, 7, and 14 d after inoculation. Wildtype mice cleared 99.5% of pulmonary M. pulmonis by 3 d after infection but remained chronically infected through the study. SRA−/− mice were chronically infected with 40-fold higher mycoplasma numbers than were wildtype mice. M. pulmonis caused a chronic mixed inflammatory response that was accompanied with high levels of IL1β, KC, MCP1, and TNFα in SRA−/− mice, whereas pulmonary inflammation in WT mice was represented by a monocytosis with elevation of IL1β. Housing had a prominent influence on the severity and persistence of mycoplasmosis in SRA−/− mice. SRA-/- mice housed in static cages had an improved recovery and significant changes in surfactant proteins SPA and SPD compared with baseline levels. These results indicate that SRA is required to prevent chronic mycoplasma infection of the lung. Furthermore, environmental conditions may exacerbate chronic inflammation in M. pulmonis-infected SRA−/− mice.Abbreviations: BAL, bronchoalveolar lavage; COPD, chronic obstructive pulmonary disease; KC, keratinocyte-derived chemokine (CXCL1); MCP1, monocyte chemotactic protein 1; SPA, surfactant protein A (SFTPA1); SPB, surfactant protein B (SFTPB); SPD, surfactant protein D (SFTPD); SRA, class A scavenger receptor (MSR1); WT, wildtypeThere are numerous options for the housing and husbandry of rodents in the laboratory setting. Various available choices in caging, bedding material, and cage-change frequency have the potential to effect physiologic values and thus experimental outcomes.20,108 In many facilities, current practices involve performing cage changes every 1 to 2 wk, with some facilities exploring the possibility of extending these practices to every 4 wk.97 Cage-change frequency practices are established at various institutions after consideration of several variables that affect animal health, welfare, and cost. Ideally, an appropriate sanitation program provides clean and dry bedding, adequate air quality, and clean cage surfaces and accessories.44 When establishing performance standards for a sanitation program that are different from those which are recommended in the Guide for the Care and Use of Animals in Research,44 microenvironmental conditions, including intracage humidity, temperature, animal behavior and appearance, microbiologic loads, and levels of pollutants such as CO2 and NH3, should be evaluated and verified. Although there are currently no established NH3 exposure limits for laboratory animals, the human occupational exposure limit of 25 ppm as an 8-h time-weighted average, established by the National Institute for Occupational Safety and Health, is often referenced as a guideline for animals.95 Multiple factors, such as animal cage density, sex, age, bedding type, reusable compared with disposable caging, static caging compared with IVC, and cage-change frequency, influence intracage and ambient NH3 levels.82,83,97 Only limited information is available that addresses the effect of natural intracage NH3 levels on respiratory function in experimental rodents and whether exposure to high NH3 levels under current standard practices affects the results of respiratory disease research.Ammonia is an alkaline, corrosive, and irritant gas that is very water soluble. It reacts with the moisture of the mucous membranes of the eyes, mouth, and respiratory tract to form ammonium hydroxide in an exothermic reaction, resulting in thermal and chemical burns.68 Clinical symptoms in humans exposed to high levels of NH3 include eye irritation, headaches, and multiple acute and chronic respiratory symptoms, such as irritation of the nose, pharynx, and sinuses, and in severe cases, development of bronchitis and hyper-reactive airway disease.79 Animals are similarly susceptible to NH3-induced pulmonary disease.23,31,48Mice exposed to naturally increasing levels of intracage NH3 can develop lesions in the rostral nasal cavity, with decreasing severity of the lesions moving caudally into the nasopharynx, and no lesions in the lung.97 However, dust is another common environmental pollutant that is often present in animal settings. Dust particles readily absorb NH3, which then serve as a source of NH3 deposition into the lower respiratory tract. Dust particulate can range from large (300 µm), minimally respirable particles to very fine (< 50 µm) particulate matter, which can settle deep within the alveoli.10,102 The mucociliary system of the respiratory tract is the first line of defense against inspired noxious stimuli and pathogens. Exposure of the ciliated respiratory epithelium to the damaging effects of NH3 are known to cause decreased mucociliary beating.56 Disruption of the respiratory mucociliary escalator initiated by NH3 exposure can then promote establishment of chronic infections and inflammation of the airway mucosa.11,87 Therefore, NH3 potentially can cause pathophysiologic changes of the lung in the absence of histopathologic lesions.Our primary goal was to analyze the effect of 2 housing modalities, which result in different intracage NH3 concentrations, on mice that were challenged with a respiratory pathogen. Mycoplasma pulmonis was chosen as a model because it is a well-established model in rodents which causes chronic mycoplasmosis and reproduces the features of M. pneumoniae in humans.22,41 M. pneumoniae infection is a frequent and contagious etiology of community-acquired pneumonia causing tracheobronchitis, sneezing, cough, and inflammation of the respiratory tract.8,12,47,63 Moreover, atypical and difficult-to-detect respiratory pathogens such as Chlamydophila pneumoniae and Mycoplasma pneumoniae that can establish chronic asymptomatic infections may contribute to both the development and exacerbation of COPD26,45,57,58,62,63,66,72,96,103 and asthma.8,51,65 Infection with M. pulmonis in rodents causes rhinitis, otitis media, tracheitis, and pneumonia, which can be exacerbated by housing conditions and genetic background.14,32,85 The mechanism of pathogenicity of mycoplasmas continues to be an area of interest in the research.The innate host factors protecting against pulmonary mycoplasmosis include the secreted surfactant protein opsonins SPA and SPD, surfactant phospholipids, and the molecular pattern-recognition receptor TLR2.15,16,54,74 Therefore, compared with their wildtype (WT) counterparts, SPA-deficient mice infected with either M. pulmonis or M. pneumoniae develop more severe inflammation and have decreased capacity to clear these infections from the lungs.43 In addition, TLR2-deficient mice exhibit decreased clearance and increased inflammation in response to mycoplasma infection.60,104Second, we wanted to study the effects of SRA deficiency in mycoplasmosis. The class A scavenger receptor (SRA) modulates inflammatory responses and mediates the clearance of airborne oxidants, particulates, and respiratory pathogens.3,17,18,49,88,101 Inhibition of SRA expression in alveolar macrophages in an elastase–LPS model of COPD was associated with decreased clearance of Haemophilus influenzae.33 Lack of SRA similarly impaired alveolar macrophage-mediated clearance of Streptococcus pneumoniae,5 environmental particles,6 and ozone-oxidized lipids18 by alveolar macrophages. Absence of SRA also enhanced hyperoxia-induced lung injury49 and exacerbated inflammation in response to Staphylococcus aureus infection.88 SRA appears to have antiinflammatory properties with the capacity to modify macrophage phenotype and suppress polarization toward the M1 alternative macrophage activation state.13 The SRA gene (MSR1) is polymorphic in both mice and humans.19,29,105 Genetic association studies in humans, however, showed that subjects with truncations or point mutations in MSR1 have significantly increased risk for the development of pulmonary diseases such as COPD33,38,71,94 and asthma.5 Our understanding of the immune factors that contribute to mycoplasmosis is far from complete.In the present study, by investigating the role of SRA in mycoplasmosis jointly with the effects of housing, we demonstrated that genetic and environmental factors both serve as critical players in disease progression. We show that SRA-deficient mice are susceptible to chronic colonization with M. pulmonis and development of chronic mycoplasma-induced bronchopneumonia characterized by persistent multicellular inflammation. Furthermore, we show that housing conditions influence the effect of SRA deficiency on the severity of mycoplasmosis. Taken together, these results indicate that lack of SRA function impairs host protection against both infectious and environmental insults.  相似文献   
33.
Hybridization between wild species and their domestic relatives can be an important conservation and management problem. Genetic purity of the wild species is desirable per se and the phenomenon can have unpredictable evolutionary consequences. Declining European wild boar populations were frequently restocked with farmed wild boars that sometimes had been crossed with domestic pigs. We used simple polymerase chain reaction‐based diagnostic tests to detect the presence of mitochondrial DNA and coat colour alleles of domestic origin in wild boars from Belgium, Luxembourg, and western Germany. Microsatellite genotypes were used to test for genetic admixture between the wild boars and domestic pigs. Although almost one‐third of all Luxembourg wild boars carried Asian mitochondrial DNA haplotypes originating from domestic pigs, microsatellite‐based clustering only identified four putatively admixed individuals in Luxembourg. By contrast, clustering identified wild boar × domestic hybrids in most sampling locations in Belgium. We interpret these results as evidence of releases of hybrid captive‐reared wild boars. Our results emphasize the need (if working with classical markers) to use different systems to obtain an understanding as to whether hybridization between wild and domestic relatives might have affected the genetic make‐up of a local population. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 104–115.  相似文献   
34.
The response of the digestive proteases to abrupt salinity change was studied in juvenile gilthead sea bream (Sparus aurata) for 15 days after transfer from 33 per thousand to 21 per thousand. Salinity decrease affected significantly neither the activity of total acid proteases in stomach, nor the activities of total alkaline proteases and major serine proteases--trypsin and chymotrypsin--in the alkaline part of the intestine. The activity of the major proteases was significantly different between the alkaline segments of the intestine, with the posterior intestine presenting the highest activities followed by the pyloric caeca. This distribution pattern remained unaffected by salinity decrease. Notably, salinity change led to significant alterations in elastase and carboxypeptidase activity. The changes were more prominent in the upper part of the intestine (pyloric caeca and anterior intestine) than in the posterior intestine. In pyloric caeca significant alteration of carboxypeptidase A and B activities was observed, elastase changes were confined to anterior intestine together with alterations in carboxypeptidase B activity, while in posterior intestine the changes were restricted to carboxypeptidase A activity. The results are discussed in relation to the osmoregulatory action of the intestinal segments and dietary protein digestion.  相似文献   
35.
36.
Summary The unusual behaviour of the 9q1 human chromosome region is studied in various conditions. In controls with normal chromosomes 9, del(9q1) is the most frequent spontaneously occurring deletion. This deletion is highly inducible by melphalan, an S phase-dependent alkylating agent. This may correspond to the uncovering of pre-existing DNA breaks in this region. In a 46,XX,9qh+ control, melphalan does not induce deletions any more efficiently than in donors with normal chromosomes 9. In a46,XY,inv(9)(p11q1205) donor, all deletions of inv(9) affect the short, but not the long, arm. This indicates that the sensitive segment is not the whole heterochromatic region, but rather a limited structure. The high rate of rearrangements affecting this structure may be responsible for somatic crossing over, leading to loss of heterozygosity for 9q, and to the frequent occurrence of inv(9) in human populations.  相似文献   
37.
Allozyme variability of 91 brown hares (Lepus europaeus) from seven regions in Greece was compared to existing data of Bulgarian populations to test the hypothesis of the occurrence of specific alleles in Greece, likely stemming from an isolated Late Pleistocene refugial population in the southern Balkans. This hypothesis is particularly suggested by some subfossil Late Pleistocene hare remains in Greece and the reported high mtDNA diversity in Greek hares. Allozymic diversity could be higher in Greek hares than in hares from neighboring regions as a result of the accumulation of variants in a long-lasting Pleistocene refugium. Conversely, Greek hares could exhibit reduced genetic diversity because of long-lasting low effective population sizes during the Late Glacial Maximum and a lower chance of postglacial gene flow from other populations into this rather marginal part in the southern Balkans. Horizontal starch gel electrophoresis of proteins from 35~loci revealed three alleles (Es-1 –162, Pep-2 114, Mpi 88) at low frequencies, which were not found in Bulgarian or any other brown hare population. In contrast, some alleles from the populations from Bulgaria and other regions of Europe were absent in the Greek samples. Population genetic statistics indicated only a slight tendency of increased gene pool diversity in Greek hares, little substructuring in Greek and Bulgarian populations, respectively, as well as an only slightly lower level of gene flow between the two neighboring regions, as compared to the gene flow within each region. The results conform to the hypothesis of a Late Pleistocene refugial population in the southern Balkans, with some few specific nuclear gene pool characteristics, but little effect on the overall genetic differentiation between Greek and Bulgarian hares.  相似文献   
38.
BACKGROUND: Primary renal synovial sarcoma is a relatively recently described and characterized neoplasm, formerly designated embryonal sarcoma of the kidney, and has not been diagnosed before by fine needle aspiration biopsy cytology. We describe the cytologic features of a malignant biphasic neoplasm of the kidney that was subsequently diagnosed at nephrectomy and confirmed with molecular genetic analysis as a biphasic renal synovial sarcoma. CASE: A 38-year-old male presented with acute abdominal pain. Computed tomography (CT) demonstrated a 4.7-cm mass in the left kidney. No soft tissue or extrarenal masses were identified. A CT-guided fine needle aspiration biopsy revealed a malignant biphasic tumor characterized by minimally atypical tubular epithelium, immature spindle cells and foci of coagulative tumor necrosis. At nephrectomy, a necrotic, pseudo-encapsulated synovial sarcoma of the upper pole of the left kidney was identified and was additionally evaluated with immunohistochemistry and molecular genetic studies. The case is unique since biphasic synovial sarcomas have yet to be reported to occur in the kidney and fine needle aspiration biopsy findings of this renal neoplasm have never been reported to our knowledge. CONCLUSION: Synovial sarcoma should be a diagnostic consideration particularly in a young adult with a malignant spindle cell neoplasm of the kidney. The list of differential diagnoses should include sarcomatoid renal cell carcinoma, sarcomatoid transitional cell carcinoma of the renal pelvis, angiomyolipoma and monophasic or biphasic synovial sarcoma.  相似文献   
39.
2-Acetamido-2-deoxy-D-glucono-1,4-lactone (1) and 2-acetamido-2-deoxy-D-gluconic acid (3) have been examined for inhibitory activity against 2-acetamido-2-deoxy-β-D-glucosidase from bull epididymis. Crystalline 1 and 3 were compared with the known, crystalline 2-acetamido-2-deoxy-D-glucono-1,5-lactone (2), and a correlation of the activities of these compounds with various factors is presented. The inhibition constant of the 1,5-lactone 2 is lower (0.45μM) than that (4.43μM) of the 1,4-lactone 1. The effect of time is the opposite; whereas the activity of solutions of 2 decreases with time, solutions of 1 show an increase in inhibitory power, but both reach an equilibrium after 5 h. The free acid 3 exhibits no inhibitory activity. 2-Acetamido-2-deoxy-5,6-O-isopropylidene-D-glucono- 1,4-lactone (4) and 2-acetamido-2-deoxy-4,6-O-isopropylidene-D-glucono-1,5-lactone (5), which are appropriately protected to prevent conversion into the other lactone isomer, were also tested; 4 has 1/1000th the activity of 5.  相似文献   
40.
We describe a novel mutation in human mitochondrial NADH dehydrogenase 1 gene (ND1), a G to A transition at nucleotide position 3337, which is co-segregated with two known mutations in tRNALeu(CUN) A12308G and tRNAThr C15946T. These mutations were detected in two unrelated patients with different clinical phenotypes, exhibiting cardiomyopathy as the common symptom. The ND1 G3337A mutation that was detected was found almost homoplasmic in the two patients and it was absent in 150 individuals that were tested as control group. Mitochondrial respiratory chain complex I activity of the patients platelets was also tested and found decreased compared to those of controls. We suggest that the co-existence of mutations in tRNA and ND1 genes may act synergistically affecting the clinical phenotype. Our study highlights the enormous phenotypic diversity that exists among pathogenic mtDNA mutations and re-emphasizes the need for a more careful clinical approach.  相似文献   
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