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1.
This ecologic study aimed to investigate whether differences in population mortality from lung, stomach and colorectal cancer among the 16 cohorts of the Seven Countries Study could be explained by differences in the average intake of anti-oxidant (pro)vitamins. In the 1960s, detailed dietary information was collected in small sub-samples of the cohorts by the dietary record method. In 1987, food-equivalent composites representing the average food intake of each cohort at baseline were collected locally and analyzed in a central laboratory. The vital status of all participants was verified after 25 years of follow-up. The average intake of vitamin C was strongly inversely related to the 25-year stomach-cancer mortality (r = -0.66, p = 0.01), also after adjustment for smoking and intake of salt or nitrate. The average intake of alpha-carotene, beta-carotene, and alpha-tocopherol were not independently related to mortality from lung, stomach or colorectal cancer, nor was vitamin C related to lung and colorectal cancer.  相似文献   
2.

The use of the iris and periocular region as biometric traits has been extensively investigated, mainly due to the singularity of the iris features and the use of the periocular region when the image resolution is not sufficient to extract iris information. In addition to providing information about an individual’s identity, features extracted from these traits can also be explored to obtain other information such as the individual’s gender, the influence of drug use, the use of contact lenses, spoofing, among others. This work presents a survey of the databases created for ocular recognition, detailing their protocols and how their images were acquired. We also describe and discuss the most popular ocular recognition competitions (contests), highlighting the submitted algorithms that achieved the best results using only iris trait and also fusing iris and periocular region information. Finally, we describe some relevant works applying deep learning techniques to ocular recognition and point out new challenges and future directions. Considering that there are a large number of ocular databases, and each one is usually designed for a specific problem, we believe this survey can provide a broad overview of the challenges in ocular biometrics.

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3.
The AIF/CypA complex exerts a lethal activity in several rodent models of acute brain injury. Upon formation, it translocates into the nucleus of cells receiving apoptotic stimuli, inducing chromatin condensation, DNA fragmentation, and cell death by a caspase-independent mechanism. Inhibition of this complex in a model of glutamate-induced cell death in HT-22 neuronal cells by an AIF peptide (AIF(370-394)) mimicking the binding site on CypA, restores cell survival and prevents brain injury in neonatal mice undergoing hypoxia-ischemia without apparent toxicity. Here, we explore the effects of the peptide on SH-SY5Y neuroblastoma cells stimulated with staurosporine (STS), a cellular model widely used to study Parkinson’s disease (PD). This will pave the way to understanding the role of the complex and the potential therapeutic efficacy of inhibitors in PD. We find that AIF(370-394) confers resistance to STS-induced apoptosis in SH-SY5Y cells similar to that observed with CypA silencing and that the peptide works on the AIF/CypA translocation pathway and not on caspases activation. These findings suggest that the AIF/CypA complex is a promising target for developing novel therapeutic strategies against PD.  相似文献   
4.
Iron regulatory proteins (IRPs) control the synthesis of several proteins in iron metabolism by binding to iron-responsive elements (IREs), a hairpin structure in the untranslated region (UTR) of corresponding mRNAs. Binding of IRPs to IREs in the 5' UTR inhibits translation of ferritin heavy and light chain, erythroid aminolevulinic acid synthase, mitochondrial aconitase, and Drosophila succinate dehydrogenase b, whereas IRP binding to IREs in the 3' UTR of transferrin receptor mRNA prolongs mRNA half-life. To identify new targets of IRPs, we devised a method to enrich IRE-containing mRNAs by using recombinant IRP-1 as an affinity matrix. A cDNA library established from enriched mRNA was screened by an RNA-protein band shift assay. This revealed a novel IRE-like sequence in the 3' UTR of a liver-specific mouse mRNA. The newly identified cDNA codes for a protein with high homology to plant glycolate oxidase (GOX). Recombinant protein expressed in bacteria displayed enzymatic GOX activity. Therefore, this cDNA represents the first vertebrate GOX homologue. The IRE-like sequence in mouse GOX exhibited strong binding to IRPs at room temperature. However, it differs from functional IREs by a mismatch in the middle of its upper stem and did not confer iron-dependent regulation in cells.  相似文献   
5.
Two-hundred and fourteen patients with congestive heart failure were identified over a six-month period in the general practice of 29 GPs covering an adult population of 29,959 subjects residing in the region of Calabria, in southern Italy, with an overall prevalence of 7 per 1000. Males represented 52% of the cases and females 48%, with a median age of 75 years. On average, the condition was first diagnosed 41 months before the present examination. Patients generally had a high body mass index (28 kg/m2). Patients were classified as follows in the NYHA classification: 9.4% in class I, 45.3% in class II, 39.2% in class III, 6.1% in class IV. Hypertension, either alone or associated with ischemic heart disease (totally about 75% of cases), was the most common etiology, while COPD was the most commonly associated chronic condition. Clinical symptoms and signs were used to classify patients in a simplified version of the Boston score which was reported in 48% of cases as definite, 12% as possible, 6% as improbable and 34% as absent. A specific treatment was already ongoing in 97% of patients. The most commonly administered drugs were diuretics (83%), ACE-inhibitors (77%), and digitalis (67%). This three-drug combination (alone or with other drugs) covered 46% of patients. A comparison of four predefined typologies of treatment against the Boston score suggested that at least part of the outcome in classifying patients using this procedure was due to pathomorphosis of the syndrome induced by early pharmacological treatment.  相似文献   
6.
This study presents the synthesis of the novel protected O‐glycosylated amino acid derivatives 1 and 2 , containing βGalNAc‐SerOBn and βGalNAc‐ThrOBn units, respectively, as mimetics of the natural Tn antigen (αGalNAc‐Ser/Thr), along with the solid‐phase assembly of the glycopeptides NHAcSer‐Ala‐Pro‐Asp‐Thr[αGalNAc]‐Arg‐Pro‐Ala‐Pro‐Gly‐BSA ( 3 ‐BSA) and NHAcSer‐Ala‐Pro‐Asp‐Thr[βGalNAc]‐Arg‐Pro‐Ala‐Pro‐Gly‐BSA ( 4 ‐BSA), bearing αGalNAc‐Thr or βGalNAc‐Thr units, respectively, as mimetics of MUC1 tumor mucin glycoproteins. According to ELISA tests, immunizations of mice with βGalNAc‐glycopeptide 4 ‐BSA induced higher sera titers (1:320 000) than immunizations with αGalNAc‐glycopeptide 3 ‐BSA (1:40 000). Likewise, flow cytometry assays showed higher capacity of the obtained anti‐glycopeptide 4 ‐BSA antibodies to recognize MCF‐7 tumor cells. Cross‐recognition between immunopurified anti‐βGalNAc antibodies and αGalNAc‐glycopeptide and vice versa was also verified. Lastly, molecular dynamics simulations and surface plasmon resonance (SPR) showed that βGalNAc‐glycopeptide 4 can interact with a model antitumor monoclonal antibody (SM3). Taken together, these data highlight the improved immunogenicity of the unnatural glycopeptide 4 ‐BSA, bearing βGalNAc‐Thr as Tn antigen isomer.  相似文献   
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8.
Blood lead (B-Pb) levels were determined in 1802 out of 1856 non-occupationally exposed men aged 55-75 years living in the Rome area who participated, between 1989 and 1990, in an epidemiological survey for coronary heart disease (New Risk Factors Project). The median B-Pb level was 113 micrograms/l (10th-90th centiles: 74-180 micrograms/l) and only 0.7 per cent (n = 14) of the subjects had B-Pb values higher than 300 micrograms/l. B-Pb levels were significantly and positively associated to alcohol consumption. Moderate and heavy drinkers had median B-Pb level of 143 micrograms/l (10th-90th centiles: 92-233) and 165 micrograms/l (10th-90th centiles: 102-285) respectively, whereas non-drinkers had a median B-Pb level of 96 micrograms/l (10th-90th centiles: 66-143). The influence of smoking habits was less relevant. Subjects who never smoked and subjects smoking more than 20 cigarettes daily had median B-Pb levels of 103 and 133 micrograms/l, respectively. Individuals classified as habitual car-drivers had slightly higher Pb levels than non-drivers. Subjects classified as manual workers had higher B-Pb levels in comparison with non-manual workers and retired subjects. B-Pb levels were directly related to HDL-cholesterol (HDL-C, r = 0.2252) and gamma-glutamyltransferase (gamma-GT, r = 0.2207) serum levels. The alleged alcohol consumption was more related to B-Pb level (r = 0.3848) than to serum level of HDL-C (r = 0.2474) or gamma-GT (r = 0.2469). A significant correlation (r = 0.2409) also existed between B-Pb and blood cadmium levels (B-Cd). Subjects with a low Gaensler ratio, an index of respiratory function, had higher B-Pb levels. In multiple regression analyses alcohol intake was the most important predictor of B-Pb level, explaining more (14.27%) of the total variance than did B-Cd (4.98%), HDL-C (1.89%), driving habits (1.46%), gamma-GT (1.09%), skinfold thickness (0.96%), and Gaensler index (0.38%). The risk ratio of having B-Pb level higher than 180 micrograms/l (90th centile of B-Pb distribution in our subjects) was 5.3 (95% CI: 2.7-10.4) for drinkers versus non-drinkers and 1.9 (95% CI: 1.2-3.1) for current smokers versus subjects who had never smoked. B-Pb was, at least in our subjects, a more specific and sensitive objective index of alcohol consumption than gamma-GT and HDL-C.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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10.
BACKGROUND: Are trends in coronary heart disease deaths based on risk factor changes? OBJECTIVE: To study the relationship between trends in coronary deaths and changes in blood cholesterol in the Seven Countries Study. MATERIAL AND METHODS: Sixteen cohorts of men aged 40-59 years from seven countries (U.S.A., Finland, the Netherlands, Italy, Croatia (former Yugoslavia), Serbia (former Yugoslavia), Greece, Japan) were units for the analyses of serum cholesterol measured at entry and after 5 and 10 years, and for mortality over 25 years. RESULTS: In the populations, the ecological relationship of mean serum cholesterol at entry to late coronary heart disease death rates during the 10- to 25-year follow-up was weak, with an R-square of 0.31. Cholesterol measurements made at year 10, and an indicator of cholesterol change during the first 10 years, increased the association (R-square, 0.49). A negative and significant interaction was shown between baseline population cholesterol levels and their 10-year change. As an indicator of acceleration in mortality, cholesterol change over 10 years was also positively correlated (partial R-square 0.44) with the ratio of 25-year to 5-year deaths. CONCLUSIONS: In the Seven Countries Study, late coronary heart disease death rates are largely "explained' by changes in blood cholesterol levels during the early phases of the study, mainly due to increases in lower cholesterol levels among some cohorts.  相似文献   
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