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991.
JY Jung IY Kim YN Kim JS Kim JH Shin ZH Jang HS Lee GS Hwang JK Seong 《BMB reports》2012,45(7):419-424
High-fat diets (HFD) and high-carbohydrate diets (HCD)- induced obesity through different pathways, but the metabolic differences between these diets are not fully understood. Therefore, we applied proton nuclear magnetic resonance ((1)H NMR)-based metabolomics to compare the metabolic patterns between C57BL/6 mice fed HCD and those fed HFD. Principal component analysis derived from (1)H NMR spectra of urine showed a clear separation between the HCD and HFD groups. Based on the changes in urinary metabolites, the slow rate of weight gain in mice fed the HCD related to activation of the tricarboxylic acid cycle (resulting in increased levels of citrate and succinate in HCD mice), while the HFD affected nicotinamide metabolism (increased levels of 1-methylnicotineamide, nicotinamide-N-oxide in HFD mice), which leads to systemic oxidative stress. In addition, perturbation of gut microflora metabolism was also related to different metabolic patterns of those two diets. These findings demonstrate that (1)H NMR-based metabolomics can identify diet-dependent perturbations in biological pathways. 相似文献
992.
993.
Kim SH Lee IC Lim JH Moon C Bae CS Kim SH Shin DH Kim HC Kim JC 《Laboratory animal research》2012,28(1):11-16
This study was conducted to investigate the potential effects of α-chlorohydrin (ACH) on epididymal function and antioxidant system in male rats. The test chemical was administered to male rats by gavage at doses of 0, 3, 10, and 30 mg/kg/day for 7 days. Twenty-four male rats were randomly assigned to four experimental groups, with six rats in each group. Spermatotoxicity was assessed by measurement of reproductive organ weight, testicular sperm head count, epididymal sperm motility and morphology, histopathologic examination, and oxidative damage analysis in rats. At 30 mg/kg/day, an increase in the incidence of clinical signs, epididymis weight, and gross necropsy findings of the epididymis, a decrease in the sperm motility, and an increased incidence of histopathological changes of the epididymis were observed in a dose-dependent manner. At 10 mg/kg/day, an increased incidence of clinical signs and histopathological changes and decreased sperm motility were observed. In the oxidative damage analysis, an increase in the malondialdehyde concentration and a decrease in the glutathione content and glutathione peroxidase and catalase activities in the epididymal tissue were detected at ≥3 mg/kg/day. The results show that graded doses of ACH elicit depletion of the antioxidant defense system and that the spermatotoxicity of ACH may be due to the induction of oxidative stress. 相似文献
994.
995.
Tae-Joon Shin Hyeon-Joong Kim Byeong-Jae Kwon Sun-Hye Choi Hyun-Bum Kim Sung-Hee Hwang Byung-Hwan Lee Sang-Mok Lee R. Suzanne Zukin Ji-Ho Park Hyoung-Chun Kim Hyewhon Rhim Joon-Hee Lee Seung-Yeol Nah 《Molecules and cells》2012,34(6):563-572
Ginseng has been shown to have memory-improving effects in human. However, little is known about the active components and the molecular mechanisms underlying its effects. Recently, we isolated novel lysophosphatidic acids (LPAs)-ginseng protein complex derived from ginseng, gintonin. Gintonin activates G protein-coupled LPA receptors with high affinity. Gintonin activated Ca2+-activated Clchannels in Xenopus oocytes through the activation of endogenous LPA receptor. In the present study, we investigated whether the activation of LPA receptor by gintonin is coupled to the regulation of N-methyl-d-aspartic acid (NMDA) receptor channel activity in Xenopus oocytes expressing rat NMDA receptors. The NMDA receptor-mediated ion current (I NMDA ) was measured using the two-electrode voltage-clamp technique. In oocytes injected with cRNAs encoding NMDA receptor subunits, gintonin enhanced I NMDA in a concentration-dependent manner. Gintonin-mediated I NMDA enhancement was blocked by Ki16425, an LPA1/3 receptor antagonist. Gintonin action was blocked by a PLC inhibitor, IP3 receptor antagonist, Ca2+ chelator, and a tyrosine kinase inhibitor. The site-directed mutation of Ser1308 of the NMDA receptor, which is phosphorylated by protein kinase C (PKC), to an Ala residue, or co-expression of receptor protein tyrosine phosphatase with the NMDA receptor attenuated gintonin action. Moreover, gintonin treatment elicited a transient elevation of [Ca2+]i in cultured hippocampal neurons and elevated longterm potentiation (LTP) in both concentration-dependent manners in rat hippocampal slices. Gintonin-mediated LTP induction was abolished by Ki16425. These results indicate that gintonin-mediated I NMDA potentiation and LTP induction in the hippocampus via the activation of LPA receptor might be responsible for ginseng-mediated improvement of memory-related brain functions. 相似文献
996.
Cho SY Jeong EM Lee JH Kim HJ Lim J Kim CW Shin DM Jeon JH Choi K Kim IG 《Molecules and cells》2012,33(3):235-241
The activation of transglutaminase 2 (TG2), an enzyme that catalyzes post-translational modifications of proteins, has been
implicated in apoptosis, cell adhesion and inflammatory responses. We previously reported that intracellular TG2 is activated
under oxidative stress conditions, such as ultraviolet irradiation, ischemia-reperfusion, and hypoxia. In this study, we examined
the effect of genotoxic stress on the intracellular activity of TG2 using doxorubicin which generates reactive oxygen species
that lead to double-strand breakage of DNA. We demonstrated that doxorubicin elicits the persistent activation of TG2. Doxorubicin-induced
TG2 activity was suppressed by treatment with caffeine at the early phase, N-acetylcysteine at the mid-phase, and EGTA at
the late phase. However, treatment with a blocking antibody against TGFβ or toll-like receptor 2 showed no effect on TG2 activity,
indicating that at least three different signaling pathways may be involved in the process of TG2 activation. In addition,
using MEF cells defective for TG2 and cells overexpressing an activesite mutant of TG2, we revealed that doxorubicin-induced
cell death is inversely correlated with TG2 activity. Our findings indicate that the persistent activation of TG2 by doxorubicin
contributes to cell survival, suggesting that the mechanism-based inhibition of TG2 may be a novel strategy to prevent drug-resistance
in doxorubicin treatment. 相似文献
997.
998.
The green-lipped mussel Perna viridis is distributed widely in the estuarine and coastal areas of the Indo-Pacific region and extensively cultured as an inexpensive protein source. Morphology and immunological activities of hemocytes of P. viridis were investigated using flow cytometry and light and electron microscopy. Three major types of hemocytes were identified in the hemolymph, including dense-granulocyte, semi-granulocyte (small and large size) and hyalinocyte. Other hemocytes, which occurred in low numbers, included granulocytes with different electron-dense/lucent granules and hemoblast-like cells. Based on flow cytometry, two subpopulations were identified. Granulocytes were larger cells, and the more abundant, containing numerous granules in the cytoplasm, and hyalinocytes were the smaller and less abundant with the fewest granules. Flow cytometry revealed that the granulocytes were more active in cell phagocytosis, contained the higher lysosomal content, and showed higher esterase activity and reactive oxygen species (ROS) generation compared with hyalinocytes. Immune functions assessed by the flow cytometry indicated that the granulocytes were the main hemocytes involved in the cellular defence in P. viridis. 相似文献
999.
Sang-Myung Jung Sung Hoon Kim Seul Ki Min Hwa Sung Shin 《In vitro cellular & developmental biology. Animal》2012,48(10):633-640
The central nervous system (CNS), once injured, rarely recovers original function mainly due to its limited regeneration ability. Astrocytes are cells that play critical roles in neural regeneration. Several biomaterials have been studied to replace and regenerate lost tissues within injured CNS. Seaweeds have extracellular polymeric substances (EPS) with bioactive properties such as antiviral and antioxidant properties. In this study, astrocyte activity was assessed, after being cultured on an electrospun polycaprolactone (PCL) nanofibrous mat containing a brown seaweed EPS. Laminarin and fucoidan, two main components of EPS extract from the brown seaweed, were concluded to increase or decrease astrocyte activity with respect to their concentration. When the concentration was under 10 ??g/ml, the astrocytes tended to increase their viability. In contrast, over 10 ??g/ml EPS in media suppressed the viability of astrocytes. In addition, when contained in PCL nanofiber, the EPS extract was also proven to influence astrocyte activity in the same way as the case when astrocytes were exposed to EPS in solution. This implies that the brown seaweed EPS?CPCL nanofiber mat can be used for temporal control of astrocyte activity by EPS concentration. Through this research, we propose that the electrospun EPS?CPCL nanofiber could be used as a nanomedicine or scaffold to treat CNS injuries. 相似文献
1000.
We studied the morphology and molecular phylogeny of Myoschiston duplicatum, a peritrich ciliate that has been recorded as an epibiont of crustaceans, but which we also identified on marine algae from Korea. The important morphological characteristics revealed by silver staining of Myoschiston species have not been described because they are rarely collected. Using morphological methods, we redescribed the type species of the genus, Myoschiston duplicatum, and provided an improved diagnosis of Myoschiston. In addition, the coding regions for nuclear small subunit (SSU) rRNA and internal transcribed spacer 1‐5.8S‐internal transcribed spacer 2 sequences were sequenced. Phylogenetic analyses that included available SSU rDNA sequences of peritrichs from GenBank strongly supported a position of M. duplicatum within the family Zoothamniidae. In addition, phylogenetic analyses were performed with single datasets (ITS1‐5.8S‐ITS2) and combined datasets (SSU rDNA + ITS1‐5.8S‐ITS2) to explore further the phylogenetic relationship in the family Zoothamniidae between the three morphologically similar genera—Zoothamnium, Myoschiston, and Zoothamnopsis. 相似文献