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21.
Lead is found in small but appreciable quantities in air, soil drinking water and food. Exposure to such amounts of lead does not cause acute lead toxicity, but produces subtle effects, particularly in children. The CDC advocates “safe” or “acceptable” levels of blood lead up to 10 μg/dl, while OSHA declares blood lead levels up to 40 μg/dl as “safe” or “acceptable” in the occupationally exposed. The objective of the study was to see if blood levels considered “safe” can cause changes in the biogenic neurotransmitters in the developing brain which may cause neurobehavioral defects like hyperactivity and other cognitive disorders. Albino Wistar rats were divided into the control and lead-treated groups. The control group was given unleaded water, while the lead-treated group was fed with 50 ppm lead acetate in drinking water. On day 45 the animals were subjected to a passive avoidance test, their blood analysed for ZPP and lead. They were then sacrificed and the neurotransmitters—Norepinephrine (NE) and its metabolite—methoxyhydroxyphenylglycol (MHPG) estimated in the brain areas associated with learning and memory—the frontal cortex, hippocampus and the striatum by HPLC-ECD. Our results showed significant increases in blood lead, NE and MHPG, while ZPP increase was insignificant. The rats showed neurobehavioral abnormalities as assessed by the passive avoidance test. We concluded that low blood levels of lead cannot be considered “safe” or “acceptable” as it causes neurotransmitter alterations. Increased NE turnover is implicated in hyperactivity disorders such as ADHD and Tourette syndrome.  相似文献   
22.
This article represents two‐firsts for the feature – it is the first to report on a study outside the UK and the first to examine the health information needs of community health workers. Sonika Raj is pursuing PhD at the Centre for Public Health, Panjab University, Chandigarh, in India and she conducted her research in Chandigarh. The article outlines the important role that health workers at community level play in determining health outcomes in the developing world, including Chandigarh. It demonstrates that while those workers recognise their information needs, there are many issues affecting their ability to access health information effectively, not least their limited access to appropriate technology and training. AM  相似文献   
23.
Research Findings: This study explored the relationship between play and child development at the Grade 1 level. As previous research has noted a sudden curtailment of classroom play during this period, the relationship between play at home and children's school grades, behavior, and creativity scores was examined using correlational and regression analyses. In particular, this study sought to assess whether particular types of play (pretend play, active physical play, construction play, etc.) and social arrangements during play (play with siblings, with parents, alone, with friends) predicted any of the outcome measures. A total of 56 children ages 6 and 7 from suburban areas outside of Montreal, as well as their parents and teachers, participated in the study. Practice or Policy: Findings indicated that children spent between 1 and 2 hr playing after school each day and that the most common form of play was active physical play. The most common social arrangement during play was play with siblings. Children's free time in the morning and freedom to choose their play activities in the afternoon were predictive of children's academic progress. Watching others play and the ability to choose their own activities in the afternoon predicted positive adaptive behaviors at school. Play with commercial toys and playing alone were predictive of creativity scores.  相似文献   
24.
Objective: To investigate molecular alterations associating with prostate carcinoma progression and potentially provide information toward more accurate prognosis/diagnosis. Methods: A set of laser captured microdissected (LCM) specimens from 300 prostate cancer (PCa) patients undergoing radical prostatectomy (RP) were defined. Ten patients representing "aggressive" PCa, and 10 representing "non-aggressive" PCa were selected based on prostate-specific antigen (PSA) recurrence,Gleason score, pathological stage and tumor cell differentiation, with matched patient age and race between the two groups.Normal and neoplastic prostate epithelial cells were collected with LCM from frozen tissue slides obtained from the RP specimens.The expressions of a panel of genes, including NPY, PTEN, AR,AMACR, DD3, and GSTP1, were measured by quantitative real-time RT-PCR (TaqMan), and correlation was analyzed with clinicopathological features. Results: The expressions of AMACR and DD3 were consistently up-regulated in cancer cells compared to benign prostate epithelial cells in all PCa patients, whereas GSTP1 expression was down regulated in each patient. NPY, PTEN and AR exhibited a striking difference in their expression patterns between aggressive and non-aggressive PCas (P=0.0203, 0.0284, and 0.0378, respectively, Wilcoxon rank sum test). The lower expression of NPY showed association with "aggressive" PCas based on a larger PCa patient cohort analysis (P=0.0037,univariate generalized linear model (GLM) analysis). Conclusion: Despite widely noted heterogeneous nature of PCa, gene expression alterations of AMACR, DD3, and GSTP1 in LCM-derived PCa epithelial cells suggest for common underlying mechanisms in the initiation of PCa. Lower NPY expression level is significantly associated with more aggressive clinical behavior of PCa; PTEN and AR may have potential in defining PCa with aggressive clinical behavior. Studies along these lines have potential to define PCa-associated gene expression alterations and likely co-regulation of genes/pathways critical in the biology of PCa onset/progression.  相似文献   
25.
Lead poisoning is well documented in persons occupationally exposed to lead. What is less known is, that even in persons working in lead based industries, the effect of lead and the appearance of signs and symptoms of lead poisoning is genetically determined. Three genes related to lead metabolism, exhibiting polymorphism have already been demonstrated-δALA-dehydratase, Vitamin D receptor gene and Hemochromatosis gene. These alleles determine the susceptibility of the individuals to lead. We present here a case of a lead acid battery worker, who presented without any signs and symptoms of lead poisoning except for a very high level of blood lead (82.8μg/dl and 47.5μg/dl 9 months later)  相似文献   
26.
A healthy civil society has long been held as vital to a healthy democracy and there is interest in whether the Internet affects this linkage. This paper explores the relationships between offline and online modes of associational life and also analyzes offline and online interactions with local governments in the US context. Based on our empirical analyses of 1,203 respondents, we show that online participation is not simply an extension of offline participation, but can be distinguished in important ways. First, we find that political and community-oriented engagements cluster separately from more private-regarding engagements. Second, participants of online democratic engagement are not characterized by the SES markers associated with offline democratic engagement who are older, have higher incomes, and have lived in the community longer. Finally, we find significant links between democratic engagement with the political system and involvement with political associations (but not social and community-oriented associations).  相似文献   
27.
Recently, the model of adoption of technology in households (MATH) was developed and tested in the context of household personal computer (PC) adoption. In this study, we apply MATH to predict personal computer (PC) use. We conducted a nationwide survey including 370 households that owned at least one PC. Results indicate that attitudinal beliefs are extremely important in determining use of a PC in the household. In contrast to previous work examining adopters, normative and control beliefs were not significant in predicting use. Furthermore, several determinants of adoption that were important at different stages of the household life cycle were found nonsignificant in predicting use for the same stages of the household life cycle. Overall, the results demonstrate that the belief structure for household PC use is different from that of household PC adoption. Further, the results provide additional evidence regarding the importance of including household life cycle in studies of household technology adoption and use.  相似文献   
28.
The activity of monoamine oxidase in platelets and of dopamine beta hydroxylase in plasma was determined in patients with schizophrenia. The activity of both the enzymes was found to be considerably decreased in patients with schizophrenia when compared to the levels noted in healthy subjects.  相似文献   
29.
Heavy metals are important toxicants known to exert adverse effects in humans and animals, given sufficient exposure and accumulation in the body. This has a great concern both at personal and public health risk. Heavy metals are also known to interact with the essential trace minerals at the level of absorption and also during the metabolism. The adverse effects of the absorbed and accumulated heavy metals include neurological, reproductive, renal and hematological systems. Children are more sensitive than adults to the effects of lead. Efforts are made to understand the mechanism of the interactions of heavy metals with essential trace minerals at the level of absorption. With available sensitive and specific methodologies like Anodic Stripping Voltammetry for the evaluation of the levels of toxic heavy metals such as lead, cadmium, mercury etc., better understanding of heavy metal absorption is made possible. Due to the poor nutritional standards, risk of heavy metal exposure is still a major concern in developing countries. Studies carried out by the author have provided evidence towards the understanding of the prevailing mechanisms of metal-metal interaction at the intestinal level. During growth and development the demand for the essential minerals being at higher level, differentiation of various essential metals and heavy metals pose an inherent problem due to certain common properties shared by them. With this approach to the problem of heavy metal toxicity, it is preventable not only with environmental intervention but also by the nutritional management.  相似文献   
30.
There is ample evidence that vitamin status of an individual can have a profound influence on the resistance of Cancer. Pyridoxine is one of the water soluble vitamins playing an important role in various metabolic reactions. Aspartate aminotransferase and Alanine aminotransferase are pyridoxal phosphate requiring enzymes and their activities in erythrocytes have been used to assess the state of vitamin B6 nutrition in man. We report here the erythrocyte transaminase levels in controls and patients with early and advanced cancer of breast. Thein vitro study of vitamin B6 shows a marked difference in the per cent stimulation in patients as compared to the controls on addition of pyridoxal phosphate. The difference indicates a subclinical deficiency of vitamin B6. The possibility exists that the rapid progression of the disease could be due to lack of host resistance caused by the deficiency of vitamin B6. The possibility of an effective treatment response after enhancing the vitamin B6 status is being looked into.  相似文献   
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