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141.
To investigate the associations of uncoupling protein (UCP)2 and UCP3 gene variants with overweight and related traits, we genotyped UCP2−866G>A, UCP2Ala55Val, and UCP3−55C>T in 737 Korean children and 732 adults and collected data regarding anthropometric status and blood biochemistry. Information concerning the children's lifestyles and dietary habits was collected. The UCP2−866G>A and UCP3−55C>T gene variants showed significant associations with BMI level, waist circumference, and body weight in the children but not in the adults. Compared with −866GG carriers, the −866GA and AA carriers showed a strong decreasing trend in the risk for overweight (odds ratio (OR), 0.67; 95% confidence interval (CI), 0.45–1.01; P = 0.053). In comparison with UCP3−55CC carriers, children carrying −55CT and TT showed a significant reduction in the risk of overweight (OR, 0.67; 95% CI, 0.46–0.98; P = 0.039). There was also evidence of interactions between the effects of the combined UCP2−UCP3 genotype and obesity‐related metabolic traits. The greatest protective effect against overweight was seen in those with the combined genotype non‐UCP2−866GG and non‐UCP3−55CC, as compared with those carrying both UCP2−866GG and UCP3−55CC (OR, 0.60; 95% CI, 0.38–0.95; P = 0.030). In the subgroup with a low level of physical activity, UCP3−55CC carriers had higher BMI values than UCP3−55T carriers (16.6 ± 2.3 kg/m2 vs. 16.1 ± 1.9 kg/m2, P = 0.016). Low physical activity may aggravate the susceptibility to overweight in UCP2−866GG and UCP3−55CC carriers.  相似文献   
142.
We synthesized homologated truncated 4′-thioadenosine analogues 3 in which a methylene (CH2) group was inserted in place of the glycosidic bond of a potent and selective A3 adenosine receptor antagonist 2. The analogues were designed to induce maximum binding interaction in the binding site of the A3 adenosine receptor. However, all homologated nucleosides were devoid of binding affinity at all subtypes of adenosine receptors, indicating that free rotation through the single bond allowed the compound to adopt an indefinite number of conformations, disrupting the favorable binding interaction essential for receptor recognition.  相似文献   
143.
Two new fatty acid glucosides, 1,6-di-O-octanoyl-β-D-glucopyranose (1) and 6-O-(β-D-glucopyranosyl)-1-O-decanoyl-β-D-glucopyranose (2), were isolated from a methanol extract of the fruit of Morinda citrifolia L. along with five known saccharide fatty acid esters. The structures of these compounds were determined by combination of spectral and chemical analyses. These fatty acid glucosides exhibited inhibitory effect against copper-induced low-density lipoprotein oxidation. Compound 2 had the strongest effect, which was almost comparable to that of butylated hydroxytoluene.  相似文献   
144.
The introduction of antigen retrieval (AR) techniques has dramatically improved the sensitivity of immunohistochemical detection of various antigens in formalin-fixed, paraffin-embedded tissues. The microwave-heating and pressure-cooking procedures are the most effective AR methods reported to date. Although extensive efforts have been made to optimize AR procedures using these two methods, previous studies have not led to a standard protocol applicable to all antibodies derived from different clones. In this study we have investigated the optimal AR buffer conditions for 29 antibodies that are in common use for diagnostic purposes in hospitals worldwide. Borate (pH 8.0) and Tris buffer (pH 9.5) yielded the highest retrieved antigen immunoreactivity against most antibodies as compared to other buffers tested. In addition, the microwave pressure-cooking gave better results than microwave-heating alone. Therefore, borate (pH 8.0) or Tris (pH 9.5) buffer used in conjunction with the pressure-cooking procedure is strongly recommended for standard routine use.  相似文献   
145.
Serum IgE levels in rats infected with Paragonimus westermani]   总被引:1,自引:0,他引:1  
Paragonimus westermani is a common fluke in Korea. The present study aimed to determine serum total IgE and specific IgG levels in experimental paragonimiasis of rats. Each Wistar rat was inoculated orally with 20-25 metacercariae of P. westermani from Cambaroides similis. Before and after infection (1, 2, 3, 4, 6, 8 weeks) of P. westermani, the blood was collected from the retro-orbital venous plexus of rats and kept serum at -70 degrees C. Serum total IgE and specific IgG levels were determined by the capture and conventional enzyme-linked immunosorbent assay, respectively. The results were as follows; 1. Serum IgE values were increased to 0.18 +/- 0.042 at 2 weeks, 0.28 +/- 0.151 at 4 weeks and 0.43 +/- 0.055 at 8 weeks after infection. The absorbances of non-infected rats ranged 0.07 +/- 0.021-0.12 +/- 0.025. 2. Specific IgG values were slightly increased at 3 weeks (0.20 +/- 0.032) and gradually increased up to 8 weeks (0.31 +/- 0.067) after infection. The absorbances of non-infected rats ranged 0.11 +/- 0.035-0.18 +/- 0.019. The present results suggested that P. westermani could elevate serum IgE and specific IgG antibodies in Wistar rats which were not a good definitive host.  相似文献   
146.

Background

To improve the quality of life of colorectal cancer patients, it is important to establish new screening methods for early diagnosis of colorectal cancer.

Methodology/Principal Findings

We performed serum metabolome analysis using gas-chromatography/mass-spectrometry (GC/MS). First, the accuracy of our GC/MS-based serum metabolomic analytical method was evaluated by calculating the RSD% values of serum levels of various metabolites. Second, the intra-day (morning, daytime, and night) and inter-day (among 3 days) variances of serum metabolite levels were examined. Then, serum metabolite levels were compared between colorectal cancer patients (N = 60; N = 12 for each stage from 0 to 4) and age- and sex-matched healthy volunteers (N = 60) as a training set. The metabolites whose levels displayed significant changes were subjected to multiple logistic regression analysis using the stepwise variable selection method, and a colorectal cancer prediction model was established. The prediction model was composed of 2-hydroxybutyrate, aspartic acid, kynurenine, and cystamine, and its AUC, sensitivity, specificity, and accuracy were 0.9097, 85.0%, 85.0%, and 85.0%, respectively, according to the training set data. In contrast, the sensitivity, specificity, and accuracy of CEA were 35.0%, 96.7%, and 65.8%, respectively, and those of CA19-9 were 16.7%, 100%, and 58.3%, respectively. The validity of the prediction model was confirmed using colorectal cancer patients (N = 59) and healthy volunteers (N = 63) as a validation set. At the validation set, the sensitivity, specificity, and accuracy of the prediction model were 83.1%, 81.0%, and 82.0%, respectively, and these values were almost the same as those obtained with the training set. In addition, the model displayed high sensitivity for detecting stage 0–2 colorectal cancer (82.8%).

Conclusions/Significance

Our prediction model established via GC/MS-based serum metabolomic analysis is valuable for early detection of colorectal cancer and has the potential to become a novel screening test for colorectal cancer.  相似文献   
147.
148.
A basket‐integrated optical device is developed to consistently treat tubular tissue by centering an optical diffuser in the lumen. Four nitinol arms in conjunction with the optical diffusing applicator are deployed to induce homogeneous circumferential light emission and concentric photothermal coagulation on tracheal tissue. A 1470‐nm laser light is employed for the tissue testing at various irradiation conditions and evaluated in terms of thermal gradient and temperature evolution. Preliminary experiments on liver tissue demonstrate the concentric development of the radial thermal coagulation in the tissue (eccentric ratio = ~5.5%). The interstitial tissue temperature increases with the total amount of energy delivery (around 65°C). Ex vivo trachea testing yields up to 16.5% tissue shrinkage due to dehydration as well as uniform ablation of the cilia and goblet cells in a mucosa layer under 7‐W irradiation for 10 s. The proposed optical device may be a feasible therapeutic method to entail the circumferential coagulation in the tubular tissues in a reliable manner.   相似文献   
149.
Hypertension is a well-established etiological factor for atherogenesis. We previously showed that transgenic mice overexpressing translationally controlled tumor protein (TCTP) develop systemic arterial hypertension. In this study we explored the cardiovascular effects of TCTP overexpression and possibly of the resultant hypertension on the severity of atherosclerosis in apolipoprotein E-deficient mice. Through multiple mating of TCTP-overexpressing transgenic mice (TCTP-TG) with apolipoprotein E knock-out mice (ApoE KO), we generated non-transgenic (nTG), TCTP-TG, nTG/ApoE KO and TCTP-TG/ApoE KO mice with similar genetic background. Male mice, 7-week old, were fed a lipid-enriched Western diet for 16?weeks, and blood pressure and body weight change were monitored every 2?weeks. Plasma lipid profiles and atherosclerotic lesions in aorta were quantified at the end of study. We found that blood pressure levels of TCTP-TG and TCTP-TG/ApoE KO, were similarly elevated while nTG and nTG/ApoE KO mice were normotensive. TCTP overexpression in ApoE KO mice led to significant exacerbation of atherosclerotic lesions. Feeding Western diet resulted in increases in total cholesterol, triglyceride (TG) and low density lipoprotein, and decreased high density lipoprotein (HDL) in ApoE KO mice. No significant differences were found in plasma lipid profiles of nTG/ApoE KO and TCTP-TG/ApoE KO. This study suggests that overexpression of TCTP, which induces hypertension, also accelerates the development of atherosclerotic lesion caused by high-fat and high-cholesterol diet without significantly altering plasma lipid profiles. We conclude that TCTP-induced hypertension could increase the severity of atherosclerotic lesion and suggest that inhibition of TCTP or its signaling pathways may be a potential approach to the therapy of both diseases, hypertension and atherosclerosis.  相似文献   
150.
The human RIF1 protein controls DNA replication, but the molecular mechanism is largely unknown. Here, we demonstrate that human RIF1 negatively regulates DNA replication by forming a complex with protein phosphatase 1 (PP1) that limits phosphorylation‐mediated activation of the MCM replicative helicase. We identify specific residues on four MCM helicase subunits that show hyperphosphorylation upon RIF1 depletion, with the regulatory N‐terminal domain of MCM4 being particularly strongly affected. In addition to this role in limiting origin activation, we discover an unexpected new role for human RIF1‐PP1 in mediating efficient origin licensing. Specifically, during the G1 phase of the cell cycle, RIF1‐PP1 protects the origin‐binding ORC1 protein from untimely phosphorylation and consequent degradation by the proteasome. Depletion of RIF1 or inhibition of PP1 destabilizes ORC1, thereby reducing origin licensing. Consistent with reduced origin licensing, RIF1‐depleted cells exhibit increased spacing between active origins. Human RIF1 therefore acts as a PP1‐targeting subunit that regulates DNA replication positively by stimulating the origin licensing step, and then negatively by counteracting replication origin activation.  相似文献   
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