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751.
752.
Toll-like receptor (TLR) 2 and TLR5, but not TLR4, are required for Helicobacter pylori-induced NF-kappa B activation and chemokine expression by epithelial cells 总被引:11,自引:0,他引:11
Smith MF Mitchell A Li G Ding S Fitzmaurice AM Ryan K Crowe S Goldberg JB 《The Journal of biological chemistry》2003,278(35):32552-32560
753.
Li YY 《PloS one》2012,7(1):e30214
Background
The α-adducin Gly460Trp (G460W) gene polymorphism may be associated with susceptibility to essential hypertension (EH), but this relationship remains controversial. In an attempt to resolve this issue, we conducted a meta-analysis.Methods
Twenty-three separated studies involving 5939 EH patients and 5021 controls were retrieved and analyzed. Four ethnicities were included: Han, Kazakh, Mongolian, and She. Eighteen studies with 5087 EH patients and 4183 controls were included in the Han subgroup. Three studies with 636 EH patients and 462 controls were included in the Kazakh subgroup. The Mongolian subgroup was represented by only one study with 100 EH patients and 50 controls; similarly, only one study with 116 EH patients and 326 controls was available for the She subgroup. The pooled and ethnic group odds ratios (ORs) along with the corresponding 95% confidence intervals (95% CI) were assessed using a random effects model.Results
There was a significant association between the α-adducin G460W gene polymorphism and EH in the pooled Chinese population under both an allelic genetic model (OR: 1.12, 95% CI: 1.04–1.20, P = 0.002) and a recessive genetic model (OR: 1.40, 95% CI: 1.16–1.70, P = 0.0005). In contrast, no significant association between the α-adducin G460W gene polymorphism and EH was observed in the dominant genetic model (OR: 0.88, 95% CI: 0.72–1.09, P = 0.24). In stratified analysis by ethnicity, significantly increased risk was detected in the Han subgroup under an allelic genetic model (OR: 1.13, 95% CI: 1.04–1.23, P = 0.003) and a recessive genetic model (OR: 1.43, 95% CI: 1.17–1.75, P = 0.0006).Conclusions
In a Chinese population of mixed ethnicity, the α-adducin G460W gene polymorphism was linked to EH susceptibility, most strongly in Han Chinese. 相似文献754.
Fang Yan Yu-Shiang Lin Zhiyuan Xu Xiaofei Li Lei Zhang Ye Zhang SuFang Liu TianHong Miao 《Blood and Genomics》2017,1(3):29-32
The aim of this study was to identify the specific RhD alleles that are risk factors for stimulating allo-anti-D and develop a precise strategy for blood transfusion. To confirm the D phenotype, red blood cells suspended in saline should react to serological anti-D from three manufacturers. An antibody screen test, a saline phase test and a micro-column test were conducted to identify allo-anti-D and other allo-antibodies. RhD alleles were genotyped by PCR using sequence-specific primers. Seven hundred subjects who were either pregnant or had undergone transfusion were enrolled in our study; however, 28 samples were excluded because their RhD alleles were normal, as revealed by tests using genotyping kits. A total of 498 cases (74.1%) were RhD-null (lacking exons 1–10 of RhD), 336 were DEL RhD 1227A (20.2%), and 38 were RHD-CE (2-9) -D (5.6%). There were 136 cases (20.2%) with allo-anti-D among the 672 cases, with an allo-anti-D prevalence of 126 cases (25.3%) in 498 cases that were RhD-null, followed by 10 cases (26.3%) among 38 cases with RHD-CE (2-9) -D, and none in 366 cases with RhD1227A. RhD genetic polymorphism was observed in RhD-negative individuals. We concluded that RhD-null and partial D are risk factors for alloimmunization to the D antigen and should be transfused with Rh-negative blood. RHD1227A recipients can be transfused with RhD-positive blood. Pregnant women with the d/d and D-CE(2-9)-D alleles require appropriate anti-D prophylaxis and RhD1227A may induce a higher tolerance. 相似文献
755.
Characterization of photosynthetic pathway of plant species growing in the eastern Tibetan plateau using stable carbon isotope composition 总被引:1,自引:0,他引:1
The photosynthetic pathway of plant species collected at Menyuan, Henan, and Maduo sites, east of Tibetan Plateau, China,
during the growing season were studied using stable carbon isotopes in leaves. The 232 samples leaves analyzed belonged to
161 species, 30 families, and 94 genera. The δ13C values (from −24.6 to − 29.2 ‰) indicated that all the considered species had a photosynthetic C3 pathway. The absence of plant species with C4 photosynthetic pathway might be due to the extremely low air temperature characterizing the Tibetan Plateau. The average
δ13C value was significantly (p<0.05) different between annuals and perennials at the three considered study sites. Hence the longer-lived species had greater
water-use efficiency (WUE) than shorter-lived species, that is, longer-lived species are better adapted to the extreme environmental
conditions of the Tibetan Plateau. 相似文献
756.
In the infarcted rat heart, the increase of NO occurs in the hypertrophied myocardium of non-infarcted areas and its antihypertrophic
efficacy has been well established. As another endogenous regulator and the reliable index of heart pathology, B-type natriuretic
peptide also exhibits the antihypertrophic properties in many tissues by elevating intracellular cGMP. Several studies indicate
that natriuretic peptides family may exert some actions in part via a nitric oxide pathway following receptor-mediated stimulation
of iNOS. Therefore, it raises our great interest to ask what role NO plays in the antihypertrophic actions of B-type natriuretic
peptide in cardiomyocytes. Incubation of cardiomyocytes under mild hypoxia for 12 h caused a significant increase in cellular
protein content, protein synthesis and cell surface sizes. This growth stimulation was suppressed by exogenous B-type natriuretic
peptide in a concentration dependent manner. Furthermore, the generation of intracellular cGMP, the upregulation of iNOS mRNA
expression, the increase of iNOS activity and subsequent nitrite generation in hypertrophic cardiomyocytes was also increased
by B-type natriuretic peptide. AG, a selective iNOS inhibitor, inhibited the upregulation of iNOS expression and the increase
of iNOS activity by the combination of B-type natriuretic peptide/mild hypoxia or by the combination of 8-bromo-cGMP/mild
hypoxia. Rp-8-br-cGMP, cGMP dependent protein kinase inhibitor, attenuated the actions of B-type natriuretic peptide and 8-bromo-cGMP
which increases intracellular cGMP independent of B-type natriuretic peptide. In conclusion, our present data suggest that
B-type natriuretic peptide exerted the antihypertrophic effects in cardiomyocytes, which was partially attributed to induction
of iNOS-derived NO by cGMP pathway. 相似文献
757.
Ryanodine, a plant alkaloid, is one of the most widely used pharmacological probes for intracellular Ca(2+) signaling in a variety of muscle and non-muscle cells. Upon binding to the Ca(2+) release channel (ryanodine receptor), ryanodine causes two major changes in the channel: a reduction in single-channel conductance and a marked increase in open probability. The molecular mechanisms underlying these alterations are not well understood. In the present study, we investigated the gating behavior and Ca(2+) dependence of the wild type (wt) and a mutant cardiac ryanodine receptor (RyR2) after being modified by ryanodine. Single-channel studies revealed that the ryanodine-modified wt RyR2 channel was sensitive to inhibition by Mg(2+) and to activation by caffeine and ATP. In the presence of Mg(2+), the ryanodine-modified single wt RyR2 channel displayed a sigmoidal Ca(2+) dependence with an EC(50) value of 110 nm, whereas the ryanodine-unmodified single wt channel exhibited an EC(50) of 120 microm for Ca(2+) activation, indicating that ryanodine is able to increase the sensitivity of the wt RyR2 channel to Ca(2+) activation by approximately 1,000-fold. Furthermore, ryanodine is able to restore Ca(2+) activation and ligand response of the E3987A mutant RyR2 channel that has been shown to exhibit approximately 1,000-fold reduction in Ca(2+) sensitivity to activation. The E3987A mutation, however, affects neither [(3)H]ryanodine binding to, nor the stimulatory and inhibitory effects of ryanodine on, the RyR2 channel. These results demonstrate that ryanodine does not "lock" the RyR channel into an open state as generally believed; rather, it sensitizes dramatically the channel to activation by Ca(2+). 相似文献
758.
759.
Xin Liao Wei Zhan Jiandong Zhang Zhongsheng Cheng Lianghe Li Tian Tian Lei Yu Rui Li 《Journal of cellular biochemistry》2020,121(10):4295-4309
Colorectal cancer is one of the most common and leading malignancies globally. Long noncoding RNAs (lncRNAs) function as potentially critical regulator in colorectal cancer. LINC01234, a novel lncRNA in tumor biology, regulates the progression of various tumors. However, the tumorigenic mechanism of LINC01234 in colorectal cancer is still unclear. This study was performed with the aim to prospectively investigate clinical significance, effect, and mechanism of lncRNA LINC01234 in colorectal cancer. First, we found that LINC01234, localized in the cytoplasm, was increased in both colorectal cancer cell lines and tissues. Subsequent functional assays suggested LINC01234 knockdown suppressed cell proliferation, migration, and invasion of colorectal cancer cells, while blocked cell cycle and induced cell apoptosis. Moreover, we identified that miR-1284 was target of LINC01234, we further demonstrated a negative correlation with LINC01234 in colorectal cancer tissues and cells. Furthermore, miR-1284 targeted and suppressed tumor necrosis factor receptor–associated factor 6 (TRAF6). Loss-of-function assay revealed that LINC01234 silencing suppressed colorectal cancer progression through inhibition of miR-1284. In vivo subcutaneous xenotransplanted tumor model indicated LINC01234 knockdown inhibited in vivo tumorigenic ability of colorectal cancer via downregulation of TRAF6. Collectively, this study clarified the biological significance of LINC01234/miR-1284/TRAF6 axis in colorectal cancer progression, providing insights into LINC01234 as novel potential therapeutic target for colorectal cancer therapeutic from bench to clinic. 相似文献
760.