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1.
《L'Anthropologie》2021,125(1):102836
In this paper, I contend that children had a unique position in prehistoric social systems, functioning as primary assimilators of new technologies. Their role is especially crucial at significant turning points in history, due to a number of childhood-cognitive mechanisms that are activated in learning and playing while engaging in innovative activity. I suggest that these mechanisms developed as part of an evolutionary process that has enabled humans to better adapt to change and prosper. This line of thinking is demonstrated through a synthesis of evolutionary, cognitive-psychological models and a case study from the archaeological record of the Levantine late Lower Paleolithic. In this time, humans developed a set of creative innovations which had to be learned and assimilated, such as the innovative production of blades. I argue that these cultural changes were successfully assimilated by groups inhabiting the Levant due to the enhancement of well-established learning mechanisms, in which children played a significant role. This role might have given them a unique status in their group – as preserving old traditions practiced by their ancestors but also as active agents, part of a collective group effort of tackling present and future challenges.  相似文献   
2.
This article analyzes the effect of bodyweight on socioemotional skills for children aged two to 12 years in Chile. Using an instrumental variable approach and a representative survey, we show that both BMI and obesity are causality related to children’s socioemotional development, even after assuming that our instrument is imperfect. Although we did not find significant differences between boys and girls, we do identify heterogeneous effects by age: the weight penalty for girls starts earlier than for boys. Our findings suggest that early interventions for childhood obesity not only might generate positive impacts on children’s health, but also a greater accumulation of non-cognitive human capital in the future.  相似文献   
3.
Although great advances have been made in the treatment of pediatric acute lymphoblastic leukemia, up to one of five patients will relapse, and their prognosis thereafter is dismal. We have previously identified recurrent deletions in TBL1XR1, which encodes for an F-box like protein responsible for regulating the nuclear hormone repressor complex stability. Here we model TBL1XR1 deletions in B-precursor ALL cell lines and show that TBL1XR1 knockdown results in reduced glucocorticoid receptor recruitment to glucocorticoid responsive genes and ultimately decreased glucocorticoid signaling caused by increased levels of nuclear hormone repressor 1 and HDAC3. Reduction in glucocorticoid signaling in TBL1XR1-depleted lines resulted in resistance to glucocorticoid agonists, but not to other chemotherapeutic agents. Importantly, we show that treatment with the HDAC inhibitor SAHA restores sensitivity to prednisolone in TBL1XR1-depleted cells. Altogether, our data indicate that loss of TBL1XR1 is a novel driver of glucocorticoid resistance in ALL and that epigenetic therapy may have future application in restoring drug sensitivity at relapse.  相似文献   
4.
BackgroundExploring the effect of maternal and/or childhood diet on offspring leukemogenesis is challenging, given differences in food group categories, their potentially variable impact depending on time window of exposure and the multiple leukemia subtypes. We opted to quantitatively synthesize published data on the association of maternal/child diet with leukemia risk.MethodsMedline was searched until June 30th, 2016 for eligible articles on the association of childhood leukemia with consumption of (i) food groups, excluding alcoholic and non-alcoholic beverages, and (ii) specific dietary supplements before/during index pregnancy and childhood.ResultsEighteen studies of case-control design (N = 11,720 cases/18,721 controls) were included, of which nine assessed maternal dietary components, five index child’s and four both, mainly focusing on acute lymphoblastic leukemia (ALL). Statistically significant inverse estimates for ALL were found (2 studies, 413 cases, 490 controls) for fruit (OR: 0.81, 95% CI: 0.67, 0.99); vegetables (OR: 0.51, 95% CI: 0.28, 0.94); legumes (OR: 0.76, 95% CI: 0.62, 0.94); fish (OR: 0.27, 95% CI: 0.14, 0.53, among the 0–4 year old; 2 studies 215 cases, 215 controls); preconception folic acid supplementation (OR: 0.69, 95%CI: 0.50–0.95; published meta analysis plus 2 studies, 3511 cases, 6816 controls); and use of vitamins during pregnancy (OR: 0.81, 95%CI: 0.74–0.88; published meta analysis plus one study, 5967 cases, 8876 controls). The associations (2 studies) of the remaining food groups and maternal dietary supplements consumption during pregnancy as well as of childhood diet and supplements intake (2–4 studies) were non significant.ConclusionsMaternal consumption of specific food groups comprising“healthy” items of the Mediterranean diet, preconception use of folic acid and intake of vitamins during pregnancy were associated with decreased ALL risk. Further research is needed, however preferably with homogeneous dietary information and data on immunophenotypic/cytogenetic subtypes to also explore the interaction of specific macro- and micronutrients intake with gene polymorphisms.  相似文献   
5.

Background

Until now, the major prognostic factors for pediatric acute lymphoblastic leukemia (ALL), age, white blood cell count and chromosomal alterations are initially taken into account for the risk stratification of patients. In the light of protein marker studies to classify subtypes of Acute Myeloblastic Leukemia efficiently, we have compared the lymphoblastes proteome in Childhood ALL in accordance with the presence of t(12;21), indicator of good prognosis, usually.

Methods

Protein expression in pre-B2 lymphoblastic cells, collected from residual bone marrow cells after diagnostic procedures, was analyzed using two dimensional gel electrophoresis protocol. Protein spots whose average normalized volumes were statistically different in the two patients groups (n = 13; student t test p < 0.01), were excised. Tryptic peptides were then analyzed using a nano-LC1200 system coupled to a 6340 Ion Trap mass spectrometer equipped with a HPLC-chip cube interface. The tandem mass spectrometry peak lists extracted using the DataAnalysis program, were compared with the protein database Mascot Daemon.

Results

We focused on twelve spots corresponding to sixteen identified candidate proteins among the 26 found differentially expressed (p ≤ 0.05) regarding the presence of t(12;21). Among over expressed proteins, two proteins were implicated in cellular growth arrest (i.e. calponine 2, p ≤ 0.001 and phosphatidylinositol transfer protein beta, p ≤ 0.001) in accordance with good prognosis, while two other proteins favored cell cycle proliferation (i.e. methionine adenosyl transferase 2β, p ≤ 0.005 and heterogeneous nuclear ribonucleo-proteins A2 p ≤ 0.01) and could therefore be good marker candidates of aggressiveness. Level of expression of proteasome subunit beta type-2 (p ≤ 0.01) and protein casein kinase 2α (p ≤ 0.01) which both favored apoptosis, deubiquitinating enzyme OTUB1 (p ≤ 0.05) and MLL septin-like fusion protein MSF-B, septin 9 i4 (p ≤ 0.01) were in accord with a good prognosis related to t(12;21) lymphoblasts.

Conclusion

By drawing up the protein map of leukemic cells, these new data identified marker candidates of leukemic aggressiveness and new t(12;21) patients subgroups. These preliminary results will be in the near future confirmed by using a larger sample of pre-B2 childhood ALLs from national lymphoblastic cell collections.  相似文献   
6.
IntroductionThis population-based study aims to evaluate the association between maternal pregestational diabetes and risk of acute lymphoblastic leukemia (ALL) in the offspring.MethodsAll 241,958 children born in three Northern Italy provinces 1998–2010 were followed from birth until first cancer diagnosis (National Childhood Cancer Register), age 15 years, or 31 December 2017. We computed hazard ratio (HR) and 95% CI of ALL in relation to the presence of maternal diabetes through Cox proportional regression models.ResultsWe observed 145 cases of ALL, with a higher incidence in children born to women with pregestational diabetes compared to the others (12.4 vs 4.6). Adjusted hazard ratio of ALL was 2.6 (CI, 0.6–10.5) for maternal diabetes.DiscussionWe estimated higher risks of ALL in the offspring of women with pregestational diabetes. These results are consistent with previous findings and compatible with a role of prenatal glycaemic environment in childhood cancer aetiology.  相似文献   
7.
丝状真菌作为一类重要的微生物,被广泛应用于发酵食品、工业酶和次生代谢物等工业生产中。真菌鞘糖脂主要由鞘氨醇、脂肪酸链和特殊的极性基团组成,根据极性基团的不同,分为中性鞘糖脂和酸性鞘糖脂两大类。鞘糖脂不仅参与真菌生长、细胞分化、增殖、细胞凋亡、逆境胁迫等重要生理活动,中性鞘糖脂还可作为功能性医药用品、化妆品和保健食品的重要活性组分。本文论述了真菌鞘糖脂的主要种类、结构、生物合成途径和及其参与丝状真菌生长、分化和响应逆境胁迫的生物学功能;探讨了真菌中性鞘糖脂作为抗菌肽的靶点和酸性鞘糖脂在开发抗真菌药物中的应用;同时还综述了中性鞘糖脂作为化妆品的保湿成分或保健食品的功能成分,在改善皮肤屏障功能和预防特应性皮炎中的重要作用的相关研究进展,尤其是来源于曲霉的中性鞘糖脂,可显著增强皮肤屏障功能,并可作为益生元预防肠道损伤;另外还探讨了曲霉尤其是米曲霉作为开发中性鞘糖脂生物资源的优势。  相似文献   
8.
超氧化物歧化酶(SOD,superoxide dismutase)是植物中一种主要的抗氧化酶,在植物应对逆境胁迫及抗衰老中起重要作用。本研究从基因芯片数据中筛选获得小麦Cu/Zn-SOD基因的EST序列,通过序列比对后拼接得到小麦Cu/Zn-SOD的候选基因,利用PCR技术在小麦光温敏雄性不育材料BS366中克隆并获得该基因。通过对Cu/Zn-SOD基因序列进行生物信息学分析,结果表明,该基因拥有连续且完整的开放阅读框,长495bp,编码164个氨基酸。氨基酸序列分析发现,该蛋白具有保守的Cu/Zn-SOD功能结构域与典型的Cu/Zn-SOD三维结构,且定位于细胞质中。通过同源进化分析表明,该蛋白与二穗短柄草(Brachypodium distachyon(L.)Beauv.)和大麦(Hordeum vulgare L.)的Cu/Zn-SOD蛋白亲缘关系较近,相似度分别为89%和94%。利用实时荧光定量PCR技术对其在小麦不同组织的表达特异性及不同逆境胁迫下的表达模式进行分析,结果表明,该基因在根、茎、叶、雌蕊、雄蕊、颖壳中均有表达,属于组成型表达,且在小麦的地上部含叶绿体的组织中含量较高;同时受多种胁迫诱导,可能参与了多种胁迫诱导调控途径。通过对该基因在不同育性环境中BS366育性转换期花药中的表达模式分析,发现可育环境下,在小孢子母细胞时期和减数分裂期的表达量分别约为对照的8倍与16倍;而不育环境下,该基因表达水平无明显变化。因而推测,小麦Cu/Zn-SOD基因可能参与了光温敏雄性不育系BS366的育性调控。本研究为深入研究Cu/Zn-SOD基因在小麦中的作用机理奠定了重要基础。  相似文献   
9.
Individuals reporting persistent psychotic experiences (PEs) in the general population, but without a “need for care”, are a unique group of particular importance in identifying risk and protective factors for psychosis. We compared people with persistent PEs and no “need for care” (non‐clinical, N=92) with patients diagnosed with a psychotic disorder (clinical, N=84) and controls without PEs (N=83), in terms of their phenomenological, socio‐demographic and psychological features. The 259 participants were recruited from one urban and one rural area in the UK, as part of the UNIQUE (Unusual Experiences Enquiry) study. Results showed that the non‐clinical group experienced hallucinations in all modalities as well as first‐rank symptoms, with an earlier age of onset than in the clinical group. Somatic/tactile hallucinations were more frequent than in the clinical group, while commenting and conversing voices were rare. Participants in the non‐clinical group were differentiated from their clinical counterparts by being less paranoid and deluded, apart from ideas of reference, and having fewer cognitive difficulties and negative symptoms. Unlike the clinical group, they were characterized neither by low psychosocial functioning nor by social adversity. However, childhood trauma featured in both groups. They were similar to the controls in psychological characteristics: they did not report current emotional problems, had intact self‐esteem, displayed healthy schemas about the self and others, showed high life satisfaction and well‐being, and high mindfulness. These findings support biopsychosocial models postulating that environmental and psychological factors interact with biological processes in the aetiology of psychosis. While some PEs may be more malign than others, lower levels of social and environmental adversity, combined with protective factors such as intact IQ, spirituality, and psychological and emotional well‐being, may reduce the likelihood of persistent PEs leading to pathological outcomes. Future research should focus on protective factors and determinants of well‐being in the context of PEs, rather than exclusively on risk factors and biomarkers of disease states.  相似文献   
10.
目的:探讨支气管哮喘患儿血清25 羟维生素D3[25-(OH)D3]水平对病情严重程度及临床转归的影响。方法:选取144 例 支气管哮喘患儿为研究对象,依据病情严重程度分为轻度间歇组、轻度持续组、中度持续组及重度持续组,选取60 例健康儿童作 为对照组,检测血清25-(OH)D3 水平;在治疗4 周后应用儿童哮喘控制测试评分系统(C-ACT)对患儿哮喘控制情况给予评价,将 所有患儿分为未控制组、部分控制组及完全控制组,比较各组血清25-(OH)D3 水平的差异。结果:对照组、轻度间歇组、轻度持续 组、中度持续组、重度持续组5 组之间血清25-(OH)D3 水平存在显著的统计学差异(P<0.05),从对照组到重度持续组血清25- (OH)D3 水平逐渐降低(P<0.05);完全控制组、部分控制组及未控制组三组血清25-(OH)D3 水平亦存在显著的统计学差异(P< 0.05),从完全控制组到未控制组血清25-(OH)D3 水平亦呈现逐渐降低趋势(P<0.05);血清25-(OH)D3 水平与病情严重程度呈负 相关(rs =-0.489, P<0.05),血清25-(OH)D3 水平与C-ACT 评分亦呈负相关(rs =-0.470, P<0.05);随着血清25-(OH)D3 水平下降 程度的加重,患儿发生重度持续发作、出现C-ACT 评分<19 分的风险值(OR)则逐渐增大。结论:血清25-(OH)D3 水平与哮喘患儿 病情严重程度及病情控制情况密切相关,早期血清维生素D 水平对于哮喘患儿病情及近期预后具有一定意义。  相似文献   
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