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61.
Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses.  相似文献   
62.
SUMMARY: The original RootTrace tool has proved successful in measuring primary root lengths across time series image data. Biologists have shown interest in using the tool to address further problems, namely counting lateral roots to use as parameters in screening studies, and measuring highly curved roots. To address this, the software has been extended to count emerged lateral roots, and the tracking model extended so that strongly curved and agravitropic roots can be now be recovered. Here, we describe the novel image analysis algorithms and user interface implemented within the RootTrace framework to handle such situations and evaluate the results. AVAILABILITY: The software is open source and available from http://sourceforge.net/projects/roottrace.  相似文献   
63.
Hypocryphalus mangiferae Stebbing is one of the most destructive insect pests of mango trees and is found to be associated with the transmission of causal organisms of mango sudden death disease. The present study was carried out to evaluate the toxicity of deltamethrin, bifenthrin, chlorpyrifos, emamectin benzoate, imidacloprid and spinosad in laboratory and field trials. Bioassay results showed that the toxicity of chlorpyrifos was significantly higher than deltamethrin but similar to bifenthrin. Deltamethrin and bifenthrin toxicity, however, increased significantly (P < 0.01) from day 1 to day 3. Spinosad was the least toxic compound while emamectin was the most toxic among new chemical insecticides tested, but its toxicity increased significantly from day 1 to day 5. Comparison of the efficacies of the insecticides using lethal times to produce 50% mortality (LT50) and 90% mortality (LT90) showed that the relative potencies of chlorpyrifos, emamectin, imidacloprid and spinosad were greater than bifenthrin and deltamethrin. The results of field trials showed the highest number of beetles emerged from the control twigs while significantly fewer beetles emerged from the twigs treated with bifenthrin (P < 0.05), which accounted for 12% for bifenthrin compared to that of the control. The present study demonstrated increased toxicities of systemic insecticides and chlorpyrifos compared to toxicities of deltamethrin and bifenthrin, suggesting these insecticides could be an alternative tool in a comprehensive H. mangiferae management program to eradicate the beetles from mango orchards.  相似文献   
64.
Background:Preeclampsia is a multifactorial hypertensive disorder of pregnancy with multisystem involvement. Recent studies have demonstrated that preeclampsia is associated with increased placental oxidative stress at the cellular level. The nuclear factor erythroid-2-like 2 (Nrf2) / Kelch-like ECH-associated protein 1 (Keap1) signaling is an antioxidant pathway that plays an important role in protecting cells against oxidative stress. Here, we aimed to determine the possible association between the Keap1 variants and genetic susceptibility to preeclampsia.Methods:In a case-control study, 150 preeclampsia patients and 150 women with normal pregnancy from Northern Iran were selected to evaluate the genotypes of Keap1 (rs11085735) using the polymerase chain reaction (PCR)-restriction length polymorphism (RFLP) method.Results:A significant association between genotypes of Keap1 rs11085735 polymorphism with the renal function biomarkers and the risk of preeclampsia was not found. However, the aspartate aminotransferase (AST) level was higher in the presence of the Keap1 AA genotype compared to AC and CC genotypes. We found a significantly higher prevalence of gestational diabetes mellitus (GDM) in mild- and severe- preeclampsia and also hypothyroidism in severe preeclampsia compared to controls.Conclusion:We found an association between preeclampsia with GDM and hypothyroidism. Our findings suggest that the Keap1rs11085735 polymorphism may not be a risk factor for susceptibility to preeclampsia in our studied population; however, this polymorphism could affect the activity of AST.Key Words: Gestational diabetes mellitus, Hypothyroidism, Keap1 variants, Oxidative stress, Preeclampsia  相似文献   
65.
The validation of an analytical method to quantify the antiangiogenic, (Z)-3-[2,4-dimethyl-5-(2-oxo-1,2-dihydro-indol-3-ylidenemethyl)-1H-pyrrol-3-yl]propionic acid (SU006668) for pharmacokinetic determination in a phase I clinical trial, is described. HPLC, with a gradient mobile phase and UV detection at 440 nm, was used. SU006668 was extracted from plasma by precipitation of proteins with acetonitrile. The assay was linear from 25 to 2000 ng/ml (r(2)=0.997); sensitive (limit of quantification 25 ng/ml), accurate (RE 2.6-11.9%) and reproducible (inter-batch precision C.V. 3.2%). Pharmacokinetic data for six patients are presented. They show linear pharmacokinetics with a low volume of distribution and induction at doses of 50, 100 and 200 mg/m(2).  相似文献   
66.
Thiopental (TPL) is a commonly used barbiturate anesthetic. Its binding with human serum albumin (HSA) was studied to explore the anesthetic-induced protein dysfunction. The basic binding interaction was studied by UV-absorption and fluorescence spectroscopy. An increase in the binding affinity (K) and in the number of binding sites (n) with the increasing albumin concentration was observed. The interaction was conformation-dependent and the highest for the F isomer of HSA, which implicates its slow elimination. The mode of binding was characterized using various thermodynamic parameters. Domain II of HSA was found to possess a high affinity binding site for TPL. The effect of micro-metal ions on the binding affinity was also investigated. The molecular distance, r, between donor (HSA) and acceptor (TPL) was estimated by fluorescence resonance energy transfer (FRET). Correlation between the stability of the TPL-N and TPL-F complexes and drug distribution is discussed. The structural changes in the protein investigated by circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy reflect perturbation of the albumin molecule and provide an explanation for the heterogeneity of action of this anesthetic.  相似文献   
67.
Use of the chemotherapeutic agent doxorubicin (Dox) is limited by dose-dependent cardiotoxic effects. The molecular mechanism underlying these toxicities are incompletely understood, but previous results have demonstrated that Dox induces p53 expression. Because p53 is an important regulator of the cell birth and death we hypothesized that targeted disruption of the p53 gene would attenuate Dox-induced cardiotoxicity. To test this, female 6–8 wk old C57BL wild-type (WT) or p53 knockout (p53 KO) mice were randomized to either saline or Dox 20 mg/kg via intraperitoneal injection. Animals were serially imaged with high-frequency (14 MHz) two-dimensional echocardiography. Measurements of left ventricle (LV) systolic function as assessed by fractional shortening (FS) demonstrated a decline in WT mice as early as 4 days after Dox injection and by 2 wk demonstrated a reduction of 31± 16% (P < 0.05) from the baseline. In contrast, in p53 KO mice, LV FS was unchanged over the 2 wk period following Dox injection. Apoptosis of cardiac myocytes as measured by the TUNEL and ligase reactions were significantly increased at 24 h after Dox treatment in WT mice but not in p53 KO mice. After Dox injection, levels of myocardial glutathione and Cu/Zn superoxide dismutase were preserved in p53 KO mice, but not in WT animals. These observations suggest that p53 mediated signals are likely to play a significant role in Dox-induced cardiac toxicity and that they may modulate Dox-induced oxidative stress.These two authors equally contributed to this study.  相似文献   
68.
The involvement of reactive oxygen species (ROS) in the induction of DNA damage to Escherichia coli cells caused by UVC (254 nm) irradiation was studied. We verified the expression of the soxS gene induced by UVC (254 nm) and its inhibition by sodium azide, a singlet oxygen (1O2) scavenger. Additional results showed that a water-soluble carotenoid (norbixin) protects against the lethal effects of UVC. These results suggest that UVC radiation can also cause ROS-mediated lethality.  相似文献   
69.
Online publication and online reading are gradually becoming routine for scientists and students. Most researchers now follow the scientific development in their expertise area through PubMed, Google Scholar  相似文献   
70.
ENOX2 (tNOX), a tumor‐associated cell surface ubiquinol (NADH) oxidase, functions as an alternative terminal oxidase for plasma membrane electron transport. Ubiquitous in all cancer cell lines studied thus far, ENOX2 expression correlates with the abnormal growth and division associated with the malignant phenotype. ENOX2 has been proposed as the cellular target for various quinone site inhibitors that demonstrate anticancer activity such as the green tea constituent epigallocatechin‐3‐gallate (EGCg) and the isoflavene phenoxodiol (PXD). Here we present a possible mechanism that explains how these substances result in apoptosis in cancer cells by ENOX2‐mediated alterations of cytosolic amounts of NAD+ and NADH. When ENOX2 is inhibited, plasma membrane electron transport is diminished, and cytosolic NADH accumulates. We show in HeLa cells that NADH levels modulate the activities of two pivotal enzymes of sphingolipid metabolism: sphingosine kinase 1 (SK1) and neutral sphingomyelinase (nSMase). Their respective products sphingosine 1‐phosphate (S1P) and ceramide (Cer) are key determinants of cell fate. S1P promotes cell survival and Cer promotes apoptosis. Using plasma membranes isolated from cervical adenocarcinoma (HeLa) cells as well as purified proteins of both bacterial and human origin, we demonstrate that NADH inhibits SK1 and stimulates nSMase, while NAD+ inhibits nSMase and has no effect on SK1. Additionally, intact HeLa cells treated with ENOX2 inhibitors exhibit an increase in Cer and a decrease in S1P. Treatments that stimulate cytosolic NADH production potentiate the antiproliferative effects of ENOX2 inhibitors while those that attenuate NADH production or stimulate plasma membrane electron transport confer a survival advantage. J. Cell. Biochem. 110: 1504–1511, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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