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71.
低龄婴幼儿龋(Earlychildhoodcaries,ECC)发生、发展是由多种因素共同作用,多种微生物共同参与的复杂过程。因此、了解儿童口腔内致龋微生物的种类及其与龋病的相关关系,对预防和治疗儿童龋病有着重要意义。本研究就ECC相关致龋菌及菌斑生物膜研究进展作一综述。  相似文献   
72.
Anecdotal reports suggest that people may be affected more by media coverage of animal rather than human-related abuse. Findings of the extant research regarding this apparent effect are mixed and omit certain key variables that may drive differential reactions to abuse disclosure. The goal of the current study was therefore to examine whether differences exist between individuals' emotional responses and pro-social behavior (reporting abuse) with respect to human (infant), or animal (puppy), directed abuse, and the effect of demographic and personality variables (including empathy and attitude to animals) on these responses. One hundred and twenty-three university students (104 females, 19 males) were presented with two scenarios (randomly presented to control for order effects) describing identical abuse situations but with two different “victims”—namely an infant or a puppy. Immediately after reading each scenario they were asked to indicate how much what the infant/puppy went through “bothered” them, the likelihood of their contacting the police should they know or discover the identity of the attacker, and complete the Profile of Mood States (Short Form). Results indicated that although in general participants were more bothered by the infant-than the puppy-abuse scenario, this was mediated by whether participants were current pet owners, and their level of pet attachment. Specifically, those most attached to their pet were significantly more bothered by the puppy abuse scenario than any other group. Personality and demographic characteristics were also found to relate to mood disturbance, bother rating, and willingness to contact police following each scenario.  相似文献   
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74.
部分甲基苯丙胺等新型毒品滥用群体的情况进行分析,就其群体性特征与传统毒品滥用群体特征作分析比较,提出新型毒品滥用的四个群体性特征:(1)年龄"低龄化";(2)滥用"群体化";(3)职业"多样化";(4)群体"转换化".该研究有助于新型毒品滥用的预防和控制工作,同时使我们的工作更具有针对性和实效性.  相似文献   
75.
Acute lymphoblastic leukemia (ALL) is the most frequently diagnosed cancer in children and single-nucleotide polymorphisms (SNPs) in certain genes influence risk of ALL. Although FOXO3 had been demonstrated to be involved leukemia, the role of FOXO3 polymorphisms was still not clear. In the present study, we explored the association of FOXO3 SNPs with ALL risk in Chinese children. We genotyped four polymorphisms (rs17069665 A>G, rs4945816 T>C, rs4946936 C>T, and rs9400241 A>C) of FOXO3 in 425 ALL cases and 1339 health controls. The associations were estimated by odds ratios (ORs) with their 95% confidence intervals (CIs). Further analyses were performed to explore associations of rs17069665 and rs9400241 with ALL susceptibility in terms of age, gender, immunophenotype, minimal residual disease (MRD), and other clinical characteristics. We found rs17069665 related to the increased ALL risk (OR = 1.76; 95% CI = 1.02-3.04), rs9400241 related to decreased ALL risk (OR = 0.80; 95% CI = 0.64-0.99). The effects of rs17069665 on ALL risk were more predominant in males and children < 10 years, and patients with lower rates of platelet or neutrophil. As for rs9400241, the effects were more predominant in children < 10 years, and in patients with pre B ALL, positive MRD, anemia, or hepatomegaly. In conclusion, FOXO3 gene polymorphisms influence the risk of ALL in children and might be a potential biomarker for ALL susceptibility.  相似文献   
76.
The fourth course at the International School of Bioelectromagnetics addressed various aspects of the epidemiology of exposure to electromagnetic fields (EMF). In this overview, inspired by the lectures and the discussions among participants, we summarize current knowledge on exposure to EMF and disease risk, with emphasis on studies of use of mobile phones and brain tumours and exposure to power lines and childhood leukaemia. Sources of bias and error hamper straightforward conclusions in some areas and, in order to move forward, improvements in study design and exposure assessment are necessary. The scientific evidence available to date on possible long‐term effects from exposure to ELF and RF fields is not strong enough to revise current protection limits based on the known acute effects of such exposures. Precautionary measures may be considered to reduce ELF exposure of children or exposure to RF during mobile phone use, keeping in mind that it is unclear whether they involve any preventive benefit. Possible health effects from mobile phone use in adults and in children should be investigated further by prospective epidemiological studies with improved exposure assessment and brain tumour incidence rates should be monitored. Further studies on the relation between childhood leukaemia and ELF magnetic fields would be worthwhile if they focus on heavily exposed groups and attempt to minimize possible selection bias. In conclusion, epidemiological studies conducted with appropriate diligence can play a key role in finding the answers. Bioelectromagnetics 30:511–524, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
77.
目的:探索抑郁症患者儿童期受虐对血清5.羟色胺(5-hydroxytryptamine5-HT)、多巴胺(Dopamine DA)和去甲肾上腺素(Norepinephrine NE)水平及相关因素的影响。方法:对101例抑郁症患者采用儿童受虐问卷(CTQ)、24项汉密尔顿抑郁量表(HAMD24)、自杀意念量表(SIOSS)及Beck绝望量表(BHS)评定儿童期受虐程度,抑郁严重程度,自杀意念强度和绝望严重程度。采用酶联免疫吸附法(ELLSA)测定血清5-HT、DA和NE水平。根据CTQ评分将总分≥50分,分量表≥10分定为被虐待。结果:(1)情感忽视组血清5-HT和DA水平明显低于无忽视组(35.63±62.43,62.58±79.50;P〈0.05;4.08±6.30ng/1,7.61±11.47ng/1,P〈0.05),受虐组血清NE水平虽高于无受虐组但无统计学意义;(2)情感受虐组和躯体受虐组的HAMD24评分明显高于无受虐组(30.60±9.84,26.77±6.54P〈0.05;31.00±9.59,27.79±8.23;P〈0.05).遭受性虐待组SIOSS评分明显高于无虐待组(17.07±3.29,14.26±3.63,P〈0.01)。情感受虐组BHS评分明显高于无受虐组(12.13±3.32,10.35±4.30,P〈0.05)(3)儿童期情感被忽视和躯体被虐待评分与BHS评分呈明显正相关(r=0.22,r=0.23,P〈0.05),被性虐待程度与SIOSS评分有明显相关(r=0.35,P〈0.01)。结论:儿童期情感被忽视的抑郁症患者血清5-HT和DA水平偏低,儿童期受虐的抑郁症患者可能存在下丘脑-垂体-肾上腺轴的不稳定。儿童期受虐是抑郁发作的危险因素并有更严重的抑郁症状。  相似文献   
78.
Although children with acute lymphoblastic leukemia (ALL) generally have a good outcome, some patients do relapse and survival following relapse is poor. Altered DNA methylation is highly prevalent in ALL and raises the possibility that DNA methylation-based biomarkers could predict patient outcome. In this study, genome-wide methylation analysis, using the Illumina Infinium HumanMethylation450 BeadChip platform, was carried out on 52 diagnostic patient samples from 4 genetic subtypes [ETV6-RUNX1, high hyperdiploidy (HeH), TCF3-PBX1 and dic(9;20)(p11–13;q11)] in a 1:1 case-control design with patients who went on to relapse (as cases) and patients achieving long-term remission (as controls). Pyrosequencing assays for selected loci were used to confirm the array-generated data. Non-negative matrix factorization consensus clustering readily clustered samples according to genetic subgroups and gene enrichment pathway analysis suggested that this is in part driven by epigenetic disruption of subtype specific signaling pathways. Multiple bioinformatics approaches (including bump hunting and individual locus analysis) were used to identify CpG sites or regions associated with outcome. However, no associations with relapse were identified. Our data revealed that ETV6-RUNX1 and dic(9;20) subtypes were mostly associated with hypermethylation; conversely, TCF3-PBX1 and HeH were associated with hypomethylation. We observed significant enrichment of the neuroactive ligand-receptor interaction pathway in TCF3-PBX1 as well as an enrichment of genes involved in immunity and infection pathways in ETV6-RUNX1 subtype. Taken together, our results suggest that altered DNA methylation may have differential impacts in distinct ALL genetic subtypes.  相似文献   
79.
Monitoring of thiopurine metabolites is important due to a complex metabolism with large interindividual variation, but the suitability of currently used methods has been questioned. The drawbacks include poor reproducibility, the inability to differentiate between the different analytes, as well as the use of a nontarget matrix. Further research should be directed toward measuring thiopurine metabolites in mononuclear cells, measuring the different nucleotides specifically, as well as measuring the incorporation of thioguanine into DNA. The studies should not be limited to thioguanosine nucleotides but include methylthioinosine nucleotides as well.  相似文献   
80.
Substance abuse and obesity are health disparities that may afflict Native Americans more than some other ethnic groups. One theoretical assumption concerning Native people is that the long history of dependence on foraging and subsistence agriculture may have led to selective enrichment of traits that improve genetic fitness, so called 'thrifty' or 'fat sparing' genes. We have speculated that this same selective pressure may have enriched for genetic variants that increase the risk for consumption of alcohol and drugs of abuse. Here, we report the results of a genome scan that compared findings for two consumption phenotypes: 'any drug dependence and/or regular tobacco use' and body mass index (BMI) in southwest California (SWC) Indian families. Variance component analyses from SOLAR were used to generate log of the odds ratio (LOD) scores. Evidence for linkage was found on chromosome 6 for both the 'any drug' (LOD score = 3.3) and BMI (LOD score = 2.3) phenotypes. Bivariate analyses of the two phenotypes revealed a combined LOD score of 4.1 at that location. Additional loci on chromosomes 6, 15, 16 and 21 were found for the 'any drug' phenotype, and on chromosomes 8, 16 and 18 for BMI (LOD scores ranged between 1.2 and 2.3). These results provide suggestive evidence for linkage for substance abuse and BMI in this Mission Indian population and, furthermore, provide preliminary data suggesting that 'consumption phenotypes' may share some genetic determinants.  相似文献   
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