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101.
In this paper, heavy metal biosensor based on immobilization of metallothionein (MT) to the surface of carbon paste electrode (CPE) via anti-MT-antibodies is reported. First, the evaluation of MT electroactivity was done. The attention was focused on the capturing of MT to the CPE surface. Antibodies incorporated and mixed into carbon paste were stable; even after two weeks the observed changes in signal height were lower than 5%. Further, the interaction of MT with polyclonal chicken antibodies incorporated in carbon paste electrode was determined by square-wave voltammetry. In the voltammogram, two signals--labelled as cys(MT) and W(a)--were observed. The cys(MT) corresponded to -SH moieties of MT and W(a) corresponded to tryptophan residues of chicken antibodies. Time of interaction (300 s) and MT concentration (125 μg/ml) were optimized to suggest a silver(I) ions biosensor. Biosensor (CPE modified with anti-MT antibody) prepared under the optimized conditions was then used for silver(I) ions detection. The detection limit (3 S/N) for silver(I) ions was estimated as 0.5 nM. The proposed biosensor was tested by detection spiking of silver(I) ions in various water samples (from very pure distilled water to rainwater). Recoveries varied from 74 to 104%.  相似文献   
102.
Restless legs syndrome (RLS) is a sensorimotor disorder with an age-dependent prevalence of up to 10% in the general population above 65 years of age. Affected individuals suffer from uncomfortable sensations and an urge to move in the lower limbs that occurs mainly in resting situations during the evening or at night. Moving the legs or walking leads to an improvement of symptoms. Concomitantly, patients report sleep disturbances with consequences such as reduced daytime functioning. We conducted a genome-wide association study (GWA) for RLS in 922 cases and 1,526 controls (using 301,406 SNPs) followed by a replication of 76 candidate SNPs in 3,935 cases and 5,754 controls, all of European ancestry. Herein, we identified six RLS susceptibility loci of genome-wide significance, two of them novel: an intergenic region on chromosome 2p14 (rs6747972, P = 9.03 × 10−11, OR = 1.23) and a locus on 16q12.1 (rs3104767, P = 9.4 × 10−19, OR = 1.35) in a linkage disequilibrium block of 140 kb containing the 5′-end of TOX3 and the adjacent non-coding RNA BC034767.  相似文献   
103.
104.

Objective

Sex-ratio at birth in families with previous girls is worse than those with a boy. Our aim was to prospectively study in a large maternal and child unit sex-ratio against previous birth sex and use of traditional medicines for sex selection.

Main Outcome Measures

Sex-ratio among mothers in families with a previous girl and in those with a previous boy, prevalence of indigenous medicine use and sex-ratio in those using medicines for sex selection.

Results

Overall there were 806 girls to 1000 boys. The sex-ratio was 720∶1000 if there was one previous girl and 178∶1000 if there were two previous girls. In second children of families with a previous boy 1017 girls were born per 1000 boys. Sex-ratio in those with one previous girl, who were taking traditional medicines for sex selection, was 928∶1000.

Conclusion

Evidence from the second children clearly shows the sex-ratio is being manipulated by human interventions. More mothers with previous girls tend to use traditional medicines for sex selection, in their subsequent pregnancies. Those taking such medication do not seem to be helped according to expectations. They seem to rely on this method and so are less likely use more definitive methods like sex selective abortions. This is the first such prospective investigation of sex ratio in second children looked at against the sex of previous children. More studies are needed to confirm the findings.  相似文献   
105.
The Medicago truncatula gene encoding an evolutionarily conserved antifungal defensin MtDef4.2 was cloned and characterized. In silico expression analysis indicated that MtDef4.2 is expressed in many tissues during the normal growth and development of M. truncatula. MtDef4.2 exhibits potent broad‐spectrum antifungal activity against various Fusarium spp. Transgenic Arabidopsis thaliana lines in which MtDef4.2 was targeted to three different subcellular compartments were generated. These lines were tested for resistance to the obligate biotrophic oomycete Hyaloperonospora arabidopsidis Noco2 and the hemibiotrophic fungal pathogen Fusarium graminearum PH‐1. MtDef4.2 directed to the extracellular space, but not to the vacuole or retained in the endoplasmic reticulum, conferred robust resistance to H. arabidopsidis. Siliques of transgenic Arabidopsis lines expressing either extracellularly or intracellularly targeted MtDef4.2 displayed low levels of resistance to F. graminearum, but accumulated substantially reduced levels of the mycotoxin deoxynivalenol. The data presented here suggest that extracellularly targeted MtDef4.2 is sufficient to provide strong resistance to the biotrophic oomycete, consistent with the extracellular lifestyle of this pathogen. However, the co‐expression of extracellular and intracellular MtDef4.2 is probably required to achieve strong resistance to the hemibiotrophic pathogen F. graminearum which grows extracellularly and intracellularly.  相似文献   
106.
107.
Fibroblastic preadipocyte cells are recruited to differentiate into new adipocytes during the formation and hyperplastic growth of white adipose tissue. Peroxisome proliferator-activated receptor γ (PPARγ), the master regulator of adipogenesis, is expressed at low levels in preadipocytes, and its levels increase dramatically and rapidly during the differentiation process. However, the mechanisms controlling the dynamic and selective expression of PPARγ in the adipocyte lineage remain largely unknown. We show here that the zinc finger protein Evi1 increases in preadipocytes at the onset of differentiation prior to increases in PPARγ levels. Evi1 expression converts nonadipogenic cells into adipocytes via an increase in the predifferentiation levels of PPARγ2, the adipose-selective isoform of PPARγ. Conversely, loss of Evi1 in preadipocytes blocks the induction of PPARγ2 and suppresses adipocyte differentiation. Evi1 binds with C/EBPβ to regulatory sites in the Pparγ locus at early stages of adipocyte differentiation, coincident with the induction of Pparγ2 expression. These results indicate that Evi1 is a key regulator of adipogenic competency.  相似文献   
108.
109.
Angiotensin II (Ang II) exerts its effects by activating its receptors, primarily type 1 (AT1R) and type 2 (AT2R). While the role of AT1R activation in cardiomyocyte physiology is well known, the role of AT2R in cardiomyocyte apoptosis remains controversial. To define the precise role of AT1R and AT2R in this process, we transfected HL-1 cardiomyocytes with AT1R or AT2R cDNA, and examined markers of apoptosis. We found that AT1R overexpression was associated with upregulation of endogenous AT2R expression, but AT2R overexpression did not affect endogenous AT1R expression. Caspase-3 staining indicated that overexpression of AT1R as well as AT2R resulted in cardiomyocyte apoptosis with appropriate alterations in annexin V, Bax and Bcl2 expression. Overexpression of AT1R and AT2R markedly increased IL-1β (AT2R>AT1R), iNOS (AT2R>AT1R) and eNOS expression. AT2R-induced cell apoptosis could be blocked by the iNOS selective inhibitor 1,400?W, and did not require exogenous Ang II. These findings suggest that AT2R overexpression induces cardiomyocyte apoptosis, most likely via iNOS upregulation. AT1R-mediated cardiomyocyte apoptosis may be partially mediated by upregulation of endogenous AT2R.  相似文献   
110.
Data from experimental animal models and in vitro studies suggest that both hyperlipoproteinemia and obesity predispose to development of proinflammatory pathways of macrophages within adipose tissue. The aim of this study was to analyze whether non-HDL cholesterol concentration in healthy living kidney donors (LKDs) is related to the number and phenotype of proinflammatory macrophages in visceral and subcutaneous adipose tissue. Adipose tissue samples were collected by cleansing the kidney grafts of LKDs obtained peroperatively. The stromal vascular fractions of these tissues were analyzed by flow cytometry. Proinflammatory macrophages were defined as CD14+ cells coexpressing CD16+ and high-expression CD36 as well (CD14+CD16+CD36+++), while CD16 negativity and CD163 positivity identified alternatively stimulated, anti-inflammatory macrophages. Non-HDL cholesterol concentration positively correlated to proinflammatory macrophages within visceral adipose tissue, with increased strength with more precise phenotype determination. On the contrary, the proportion of alternatively stimulated macrophages correlated negatively with non-HDL cholesterol. The present study suggests a relationship of non-HDL cholesterol concentration to the number and phenotype proportion of macrophages in visceral adipose tissue of healthy humans.  相似文献   
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