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Air pollution causes oxidative damage to macromolecules, chromosomal aberrations and changes in gene expression. We investigated the levels of oxidative stress markers [8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), 15-F(2t)-isoprostane (15-F2t-IsoP), protein carbonyls] and cytogenetic parameters [genomic frequency of translocations (F(G)/100), percentage of aberrant cells (%AB.C.) and acentric fragments (ace)] in subjects living in Prague and in the heavily polluted Ostrava region. We also compared the expression of genes participating in base excision repair (BER) and non-homologous end-joining (NHEJ). We analyzed 64 subjects from Prague and 75 subjects from Ostrava. We measured oxidative stress markers by ELISA, cytogenetic parameters by fluorescence in situ hybridization and gene expression by quantitative PCR. The levels of air pollutants (benzo[a]pyrene, B[a]P; carcinogenic polycyclic aromatic hydrocarbons, c-PAHs; benzene) measured by personal monitors were significantly elevated in Ostrava compared to Prague (p<0.001). Despite this fact, we observed no differences in biomarkers of oxidative stress between the two locations. Moreover, subjects from Ostrava were less likely to have above-median levels of %AB.C. (OR; 95% CI: 0.18; 0.05-0.67; p=0.010). Multivariate analyses revealed that subjects living in Ostrava had increased odds of having above-median levels of XRCC5 expression (OR; 95% CI: 3.33; 1.03-10.8; q=0.046). Above-median levels of 8-oxodG were associated with decreased levels of vitamins C (OR; 95% CI: 0.37; 0.16-0.83; p=0.016) and E (OR; 95% CI: 0.25; 0.08-0.75; p=0.013), which were elevated in subjects from Ostrava. We suggest that air pollution by c-PAHs affects XRCC5 gene expression, which probably protects subjects from Ostrava against the induction of a higher frequency of translocations; elevated vitamin C and E levels in the Ostrava subjects decrease the levels of 8-oxodG.  相似文献   
63.
Down syndrome (DS) is the most common genetic cause of mental retardation. It is estimated that 5-13% of persons affected by DS have seizures. Infantile spasms are the most common type of seizures and usually are well controlled with steroids and antiepileptic drugs. We present 11 children at the age of 3 years and 4 months to 10 years and 7 months with DS and infantile spasms, treated at Children's Hospital Zagreb from January 2000 until July 2009. Infantile spasms began at the age of 5 to 10.5 months in 10 children, in one child at the age of 16 months. Only one child had perinatal risk factors for the development of IS. Changes in EEG correlated to hypsarrhythmia. Infantile spasms were treated initially with antiepileptic drugs, most often with valproic acid. Treatment was inefficient in 10/11 patients. After application of ACTH, infantile spasms stopped between 7 and 15 days in 6 patients, until 28th day in 4 patients. Hypsarrhythmia vanished in all children. During follow-up period (2 years and 7 months to 9 years and 5 months) none of the children developed another type of seizures. No major epileptogenic changes were registered in EEG. Antiepileptic therapy was discontinued in 4 children (aged 4 years and 2 months to 5 years). In this group is the boy who died of heart failure. Infantile spasms associated with DS are categorized into symptomatic group. The existence of cerebral pathology and delayed psycho-motor development precedes occurrence of seizures. It is possible to achieve good control of seizures and disappearance of hypsarrhythmia with application of ACTH and antiepileptic drugs.  相似文献   
64.
The study assesses complexity of the cardiac control directed to the sinus node and to ventricles in long QT syndrome type 1 (LQT1) patients with KCNQ1-A341V mutation. Complexity was assessed via refined multiscale entropy (RMSE) computed over the beat-to-beat variability series of heart period (HP) and QT interval. HP and QT interval were approximated respectively as the temporal distance between two consecutive R-wave peaks and between the R-wave apex and T-wave end. Both measures were automatically taken from 24-hour electrocardiographic Holter traces recorded during daily activities in non mutation carriers (NMCs, n = 14) and mutation carriers (MCs, n = 34) belonging to a South African LQT1 founder population. The MC group was divided into asymptomatic (ASYMP, n = 11) and symptomatic (SYMP, n = 23) patients according to the symptom severity. Analyses were carried out during daytime (DAY, from 2PM to 6PM) and nighttime (NIGHT, from 12PM to 4AM) off and on beta-adrenergic blockade (BBoff and BBon). We found that the complexity of the HP variability at short time scale was under vagal control, being significantly increased during NIGHT and BBon both in ASYMP and SYMP groups, while the complexity of both HP and QT variability at long time scales was under sympathetic control, being smaller during NIGHT and BBon in SYMP subjects. Complexity indexes at long time scales in ASYMP individuals were smaller than those in SYMP ones regardless of therapy (i.e. BBoff or BBon), thus suggesting that a reduced complexity of the sympathetic regulation is protective in ASYMP individuals. RMSE analysis of HP and QT interval variability derived from routine 24-hour electrocardiographic Holter recordings might provide additional insights into the physiology of the cardiac control and might be fruitfully exploited to improve risk stratification in LQT1 population.  相似文献   
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This paper provides a critical overview of the literature on the relationship between psychological/psychopathological factors and metabolic control in children and adolescents with insulin dependent diabetes mellitus (IDDM). We discuss studies on individual and family psychopathological factors, as well as reports on the effects of psychoeducational/psychotherapeutic interventions on glycemic control in patients with IDDM aged <18 years. The analysis of the literature indicates that while evidence on the relationship between individual factors and metabolic control is still mixed, in part due to methodological issues, results from family studies do suggest that patients in dysfunctional families and children of parents with high degrees of psychopathology present with poor glycemic control. As for the effects of psychoeducational/psychotherapeutic interventions, limited but increasing evidence shows that they can actually contribute to improve metabolic control. We finally suggest some future underexplored avenues of research in the field, including studies on the psychopathological and neurobiological mechanisms underlying the above mentioned findings. All this body of research should provide a strong empirical rationale for allocating resources in order to include psychiatrists within the interdisciplinary diabetes health care team.  相似文献   
68.
Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65% ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity — determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS·+) found for TFM — were significantly (P < 0.05) higher on the 5th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities.  相似文献   
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In our experiments the effect of different plants on microbial activities resulting in degradation and PCB removal from long-term contaminated soil was evaluated. Total bacteria and bacteria representing the dominating microflora within rhizosphere of individual plant species – tobacco (Nicotiana tabacum), black nightshade (Solanum nigrum), horseradish (Armoracia rusticana) and goat willow (Salix caprea) planted in PCB contaminated soil as well as from the same, but non-vegetated PCBs soil, were isolated and biochemically characterized. PCB bacterial degraders, stimulated by root exudates of individual plants, were detected after isolation from rhizosphere soil and precultivation on minimal medium with biphenyl as the sole carbon source. Detection of BphA1 gene (first gene of bacterial aerobic PCB degradative pathway) in genomes of rhizosphere microorganisms was performed by nested PCR technique using previously designed specific primers. Rhizosphere of individual plants contained different bacterial species, mostly gram-negative non-fermenting bacteria of Pseudomonas, Agrobacterium, Ochrobactrum and other species. Gene BphA1 was identified in genome of only several of them. From tested species, S. caprea and A. rusticana have shown to be promising candidates for rhizoremediation purposes.  相似文献   
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