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191.
Fang Chen Bing Yan Jie Ren Rui Lyu Yanfang Wu Yuting Guo Dong Li Hong Zhang Junjie Hu 《The Journal of cell biology》2021,220(5)
Lipid droplets (LDs) are critical for lipid storage and energy metabolism. LDs form in the endoplasmic reticulum (ER). However, the molecular basis for LD biogenesis remains elusive. Here, we show that fat storage–inducing transmembrane protein 2 (FIT2) interacts with ER tubule-forming proteins Rtn4 and REEP5. The association is mainly transmembrane domain based and stimulated by oleic acid. Depletion of ER tubule-forming proteins decreases the number and size of LDs in cells and Caenorhabditis elegans, mimicking loss of FIT2. Through cytosolic loops, FIT2 binds to cytoskeletal protein septin 7, an interaction that is also required for normal LD biogenesis. Depletion of ER tubule-forming proteins or septins delays nascent LD formation. In addition, FIT2-interacting proteins are up-regulated during adipocyte differentiation, and ER tubule-forming proteins, septin 7, and FIT2 are transiently enriched at LD formation sites. Thus, FIT2-mediated nascent LD biogenesis is facilitated by ER tubule-forming proteins and septins. 相似文献
192.
Lan YY Wang Z Raimondi G Wu W Colvin BL de Creus A Thomson AW 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(9):5868-5877
193.
Xiao-Jing Wang Ying-Feng Liu Qing-Yu Wang Morito Tsuruoka Kazumasa Ohta Sheng-Xi Wu Masashi Yakushiji Takashi Inoue 《Cell and tissue research》2010,340(2):347-355
Tobacco smoking is the main risk factor associated with chronic periodontitis, but the mechanisms that underlie this relationship
are largely unknown. Recent reports proposed that nicotine plays an important role in tobacco-related morbidity by acting
through the nicotinic acetylcholine receptors (nAChRs) expressed by non-neuronal cells. The aim of this study was to investigate
whether α7 nAChR was expressed in periodontal tissues and whether it functions by regulating IL-1β in the process of periodontitis.
In vitro, human periodontal ligament (PDL) cells were cultured with 10−12 M of nicotine and/or 10−9 M of alpha-bungarotoxin (α-Btx), a α7 nAChR antagonist. The expression of α7 nAChR and IL-1β in PDL cells and the effects
of nicotine/α-Btx administration on their expression were explored. In vivo, an experimental periodontitis rat model was established,
and the effects of nicotine/α-Btx administration on expression of α7 nAChR and development of periodontitis were evaluated.
We found that α7 nAChR was present in human PDL cells and rat periodontal tissues. The expressions of α7 nAChR and IL-1β were
significantly increased by nicotine administration, whereas α-Btx treatment partially suppressed these effects. This study
was the first to demonstrate the functional expression of α7 nAChR in human PDL cells and rat periodontal tissues. Our results
may be pertinent to a better understanding of the relationships among smoking, nicotine, and periodontitis. 相似文献
194.
Dar-Shong Lin Tzu-Po Chuang Ming-Fu Chiang Che-Sheng Ho Chung-Der Hsiao Yu-Wen Huang Tsu-Yen Wu Jer-Yuarn Wu Yuan-Tsong Chen Tsai-Chuan Chen Ling-Hui Li 《Gene》2014
Xq28 duplications encompassing the methyl CpG binding protein 2 (MECP2) in males exhibit a distinct phenotype, including developmental delay, facial dysmorphism, muscular hypotonia, intellectual disability, poor or absent speech, recurrent infections and early death. The vast majority of affected males inherit the MECP2 duplication from their usually asymptomatic carrier mothers. Only a few cases with Xq28 duplication originating from de novo unbalanced X/Y translocation have been reported and the paternal origin of the aberration has only been validated in three males in the related literature. Here we present a karyotypically normal male with features characteristic of the MECP2 duplication syndrome. The genome-wide SNP genotyping shows a de novo 2.26-Mb duplication from Xq28 to the terminus. The genotypes of the SNPs within the duplicated region indicated a paternal origin. Furthermore, the results of fluorescence in situ hybridization (FISH) indicated a novel Xq:Yp translocation, characterized as der(Y)t(Y;X)(p11.32;q28), which suggests an aberrant that occurred during spermatogenesis. The phenotype is compared to the previously reported cases with Xq28 duplication originated from an unbalanced X/Y translocation, and there was no specific part of the phenotype that could be contributed to the origin of parental imbalances. This report further highlights the capacity of high-molecular cytogenetic methods, such as SNP array and FISH, in the identification of submicroscopic rearrangement, structural configuration and parental origin of aberrant while in the evaluation of children with idiopathic developmental delay and intellectual disability. 相似文献
195.
Xiaofei Feng Kangxian Li Fangming Tan Mei Zhu Jieyi Zhou Yongjun Lai Lingfeng Zeng Yingting Ye Jing Huang Xiaosong Wu Shasha Li 《Biochemistry and Biophysics Reports》2018
ObjectiveThe objective of the present study was to investigate the hepatoprotective role of Radix Fici Hirtae on acute alcohol-induced liver injury in mice.MethodsThe component of Radix Fici Hirtae was extracted using petroleum ether, chloroform, ethyl acetate and n-butanol and divided into three dose groups of high, medium and low according to the clinical man's normal dose of the 50 g crude drug/d (0.83 g/kg body weight). Saline in concentration of 10 mg/mL, 5 mg/mL and 2.5 mg/mL and a dose of mouse lavage (0.2 mL/10 g mouse body weight) were added to the solution. Histopathlogical analysis of liver was performed. Finally, liver protection was validated by examining the effect of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AKP), and lactate dehydrogenase (LDH) on the hepatic function of mice in alcohol-induced liver injury model.ResultsExcept for group with saturated n-butyl alcohol, for the rest of the groups, pathological changes of hepatic lipid and inflammatory cells infiltration were alleviated and liver sinus was normal. As compared to model group, the concentrations of AST, ALT, AKP and LDH in chloroform groups and ethyl acetate groups were significantly decreased.ConclusionsExtracts of Radix Fici Hirtae are effective for the prevention of alcohol-induced hepatic damage in mice. The results revealed that extracts of Radix Fici Hirtae could be used as hepatoprotective agent. 相似文献
196.
The RhoA/ROCK-2 signaling pathway is necessary for activated hepatic stellate cell (HSC) contraction. HSC contraction plays an important role in the pathogenesis of cirrhosis and portal hypertension. This study investigated whether aldosterone contributes to HSC contraction by activation of the RhoA/ROCK-2 signaling pathway. Primary HSCs were isolated from Sprague-Dawley rats via in situ pronase/collagenase perfusion. We found that aldosterone enhanced the contraction of a collagen lattice seeded with HSCs. This induced contraction was suppressed by the mineralcorticoid receptor (MR) inhibitor spironolactone, the ROCK-2 inhibitor Y27632, and the angiotensin II type 1 receptor (AT(1)R) inhibitor irbesartan. Moreover, actin fiber staining showed that aldosterone significantly increased actin fiber formation in HSCs. Pre-incubating with spironolactone, Y27632, or irbesartan inhibited the aldosterone-induced actin fiber reorganization. Molecularly, the effect of aldosterone on activation of HSC contraction was mediated by phosphorylated myosin light chain (P-MLC) through the RhoA/ROCK-2 signaling pathway. All these inhibitors had the ability to block aldosterone-induced protein expressions in the RhoA/ROCK-2/P-MLC cascade in HSCs. Taken together, our current study suggests that aldosterone induces contraction of activated HSCs through the activation of the RhoA/ROCK-2 signaling pathway. This finding may provide a potential therapeutic target for control of cirrhosis and portal hypertension. 相似文献
197.
In order to investigate the effect of large isoform of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) activase (RuBPCO-A)
on photosynthesis, cDNA of the enzyme (rca) was transferred to rice cultivars (Oryza sativa f. japonica cv. Nipponbare) under the control of RuBPCO small subunit gene promoter (rbcS) via Agrobacterium tumefaciens-mediated transformation. Transgenic rice plants were identified by polymerase chain reaction (PCR) and Southern and Western
blot analyses. Net photosynthetic rate (P
N) values of the T1 transgenic lines 34 (T34) and 40 (T40) were 45.26 and 46.32 % higher than that of the control plants, respectively. At the
same time, their carboxylation efficiency and RuBPCO initial activity, quantum yield of electron transport in photosystem
2 (ΦPS2), and steady state photochemical fluorescence quenching (qP) increased. In addition, heading time of the transgenic rice was advanced. Thus increasing the amount of large isoform of
RuBPCO-A in the transgenic rice might have a stimulatory effect on both photosynthesis and plant growth. 相似文献
198.
199.
水稻幼芽细胞生物膜上的赤霉素结合蛋白的结合特性 总被引:1,自引:0,他引:1
在水稻 (Oryza sativa)幼芽中存在膜结合的赤霉素结合蛋白 ,其与 GA3 结合的平衡解离常数(Kd)为 6.5× 1 0 -8mol/ L,总浓度为 0 .3 pmol· mg-1 蛋白质。结合蛋白与 GA3 结合活力在 0℃时比 2 5℃时高 1 4 0 %。它与 GA3 结合的最适 p H为 5。 GA3 与此结合蛋白的结合量随反应时间延长而增加 ,1 h达最大值 ,以后又逐渐下降。 IAA、ABA可与 GA3 竞争赤霉素结合蛋白。 相似文献
200.
Siva Wu Xiaojin Li Manjula Gunawardana Kathleen Maguire Debbie Guerrero-Given Christoph Schaudinn Charles Wang Marc M. Baum Paul Webster 《PloS one》2014,9(7)
Non-typeable Haemophilus influenzae (NTHi) is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth) stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL) of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended. 相似文献