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Changqing Zhang Xingquan Zhao Chunxue Wang Liping Liu Yuchuan Ding Fauzia Akbary Yuehua Pu Xinying Zou Wanliang Du Jing Jing Yuesong Pan Ka Sing Wong Yongjun Wang Yilong Wang 《PloS one》2015,10(3)
Background
The risk of a subsequent stroke following a minor stroke is high. However, there are no effective rating scales to predict recurrent stroke following a minor one. Therefore, we assessed the risk factors associated with recurrent ischemic stroke or transient ischemic attack (TIA) within one year of minor stroke onset in order to identify possible risk factors.Methods
Eight hundred and sixty-three non-cardioembolic ischemic stroke patients in the Chinese IntraCranial AtheroSclerosis Study that presented with minor stroke, defined as an admission National Institutes of Health stroke scale (NIHSS) score of ≤3, were consecutively enrolled in our study. Clinical information and imaging features upon admission, and any recurrent ischemic stroke or TIA within one year was recorded. Cox regression was used to identify risk factors associated with recurrent ischemic stroke or TIA within the year following stroke onset.Results
A total of 50 patients (6.1%) experienced recurrent ischemic stroke or TIA within one year of minor stroke onset. Multivariate Cox regression model identified lower admission NIHSS score (HR, 1.75; 95% CI, 1.32 to 2.33; P<0.0001), history of coronary heart disease (HR, 2.62; 95% CI, 1.17 to 5.86; P = 0.02), severe stenosis or occlusion of large cerebral artery (HR, 4.68; 95% CI, 1.87 to 11.7; P = 0.001), and multiple acute cerebral infarcts (HR, 2.61; 95% CI, 1.01 to 6.80; P = 0.05) as independent risk factors for recurrent ischemic stroke or TIA within one year.Conclusions
Some minor stroke patients are at higher risk for recurrent ischemic stroke or TIA. Urgent and intensified therapy may be reasonable in these patients. 相似文献64.
Sun Wook Cho Jae Hyun Bae Gyeong Woon Noh Ye An Kim Min Kyong Moon Kyoung Un Park Junghan Song Ka Hee Yi Do Joon Park June-Key Chung Bo Youn Cho Young Joo Park 《PloS one》2015,10(12)
Osteoporosis-related fractures are one of the complications of Graves’ disease. This study hypothesized that the different actions of thyroid-stimulating hormone receptor (TSHR) antibodies, both stimulating and blocking activities in Graves’ disease patients might oppositely impact bone turnover. Newly diagnosed premenopausal Graves’ disease patients were enrolled (n = 93) and divided into two groups: patients with TSHR antibodies with thyroid-stimulating activity (stimulating activity group, n = 83) and patients with TSHR antibodies with thyroid-stimulating activity combined with blocking activity (blocking activity group, n = 10). From the stimulating activity group, patients who had matched values for free T4 and TSH binding inhibitor immunoglobulin (TBII) to the blocking activity group were further classified as stimulating activity-matched control (n = 11). Bone turnover markers BS-ALP, Osteocalcin, and C-telopeptide were significantly lower in the blocking activity group than in the stimulating activity or stimulating activity-matched control groups. The TBII level showed positive correlations with BS-ALP and osteocalcin levels in the stimulating activity group, while it had a negative correlation with the osteocalcin level in the blocking activity group. In conclusion, the activation of TSHR antibody-activated TSH signaling contributes to high bone turnover, independent of the actions of thyroid hormone, and thyroid-stimulation blocking antibody has protective effects against bone metabolism in Graves’ disease. 相似文献
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Donghyun Ka Dayoun Kim Gyeongyun Baek Euiyoung Bae 《Biochemical and biophysical research communications》2014
Clustered regularly interspaced short palindromic repeats (CRISPRs) and CRISPR-associated (Cas) proteins constitute an RNA-guided microbial defense system against invading foreign genetic materials. Cas2 is one of the core Cas proteins found universally in all the subtypes of CRISPR-Cas systems and is required for incorporating new spacers into CRISPR loci. Cas2 homologues from different CRISPR-Cas subtypes were characterized previously as metal-dependent nucleases with different substrate preferences, and it was proposed that a pH-dependent conformational change mediates metal binding and catalysis. Here, we report the crystal structures of Streptococcus pyogenes Cas2 at three different pHs (5.6, 6.5, and 7.5), as well as the results of its nuclease activity assay against double-stranded DNAs at varying pHs (6.0–9.0). Although S. pyogenes Cas2 exhibited strongly pH-dependent catalytic activity, there was no significant conformational difference among the three crystal structures. However, structural comparisons with other Cas2 homologues revealed structural variability and the flexible nature of its putative hinge regions, supporting the hypothesis that conformational switching is important for catalysis. Taken together, our results confirm that Cas2 proteins have pH-dependent nuclease activity against double-stranded DNAs, and provide indirect structural evidence for their conformational changes. 相似文献
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Martin Flajšhans David Gela Martin Kocour Hana Buchtová Marek Rodina Martin Pšenička Vojtěch Kašpar Veronika Piačková Eliška Sudová Otomar Linhart 《Reviews in Fish Biology and Fisheries》2010,20(3):317-329
Performance and physiological traits and health of spontaneous and induced triploid tench are reviewed. Triploidy is best
induced with cold shock; with triploids exhibiting 13.5–51.5% better weight gain, 2.69–3.94% higher slaughtering value, 20–60%
lower gonadosomatic index, 0.9–4.5% higher dry matter in flesh and up to 107% more flesh fat than diploids, if farmed untill
post sexual maturity. Triploids exhibit more abdominal fat and less polyunsaturated fatty acids of the n-3 and n-6 groups
in the flesh. Triploid females are sterile, while triploid males may produce aneuploid spermatozoa with varying DNA content
(1–1.9n) which may initiate development of embryos. Triploids have milder seasonal dynamics in their erythrocyte profile than
the diploids. Thinner diffusion distance in gills of triploids than in diploids is interpreted as adaptation to lower aerobic
capacity. Triploids show neither stronger tendencies to anatomic malformations, nor have bigger affinity to parasitic diseases
than the diploids. Production of triploid tench could be an economically interesting method of farming to higher marketable
weight, bringing a relatively high product quality. 相似文献
69.
Xiangdong Wang Ka Li Hong Chen Diane Wang Yong Zhang Chunxue Bai 《Journal of cellular and molecular medicine》2010,14(4):833-839
There is growing evidence that the signal pathway between hepatocyte growth factor (HGF) and its receptor c-Met plays an important role in the development of lung cancer, although the specificity of such role is to be clarified. It seems clear that the HGF/c-Met signal contributes to the metastasis of cancer cells to the lung by stimulating the hyperproduction and overactivation of cytokines and enzymes, e.g. HGF, vascular endothelial growth factor and matrix metalloproteases. The HGF/c-Met signal may act as the candidate responsible for the development of epidermal growth factor receptor (EGFR) kinase inhibitor resistance. Experimental evidence showed that the combination of both EGFR and c-Met inhibitors had synergetic or additive therapeutic effects on lung cancer. Although the mechanism of interaction between HGF/c-Met and transforming growth factor-a/EGFR remains unclear, the cross-talk and balance between those two signal pathways are critical and necessary in the development of new therapies for lung cancer. 相似文献
70.
Ol’ga Vančová Ladislav Bačiak Svatava Kašparová Jarmila Kucharská Hector H. Palacios Jaromír Horecký Gjumrakch Aliev 《Journal of cellular and molecular medicine》2010,14(11):2667-2674
Brain energy disorders can be present in aged men and animals. To this respect, the mitochondrial and free radical theory of aging postulates that age‐associated brain energy disorders are caused by an imbalance between pro‐ and anti‐oxidants that can result in oxidative stress. Our study was designed to investigate brain energy metabolism and the activity of endogenous antioxidants during their lifespan in male Wistar rats. In vivo brain bioenergetics were measured using 31P nuclear magnetic resonance (NMR) spectroscopy and in vitro by polarographic analysis of mitochondrial oxidative phosphorylation. When compared to the young controls, a significant decrease of age‐dependent mitochondrial respiration and adenosine‐3‐phosphate (ATP) production measured in vitro correlated with significant reduction of forward creatine kinase reaction (kfor) and with an increase in phosphocreatine (PCr)/ATP, PCr/Pi and PME/ATP ratio measured in vivo. The levels of enzymatic antioxidants catalase, GPx and GST significantly decreased in the brain tissue as well as in the peripheral blood of aged rats. We suppose that mitochondrial dysfunction and oxidative inactivation of endogenous enzymes may participate in age‐related disorders of brain energy metabolism. 相似文献