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91.
Y Zhao H Zacur C Cheadle N Ning J Fan NF Vlahos 《Reproductive biology and endocrinology : RB&E》2012,10(1):72-12
ABSTRACT: BACKGROUND: Studies suggested that microRNAs influence cellular activities in the uterus including cell differentiation and embryo implantation. In assisted reproduction cycles, luteal phase support, given to improve endometrial characteristics and to facilitate the implantation process, has been a standard practice. The effect of different types of luteal phase support using steroid hormones in relation to endometrial miRNA profiles during the peri-implantation period has not seen described. This study was designed to evaluate the expression of miRNAs during the luteal phase following controlled ovarian stimulation for IVF and the influence of different luteal phase support protocols on miRNA profiles. METHODS: The study was approved by the Johns Hopkins Hospital Institutional Review Board. Endometrial biopsies were obtained on the day of oocyte retrieval from 9 oocyte donors (group I). An additional endometrial biopsy was obtained 3-5 days later (Group II) after the donors were randomized into three groups. Group IIa had no luteal-phase support, group IIb had luteal support with micronized progesterone (P), and Group IIc had luteal support with progesterone plus 17-beta-estradiol (P+E). Total RNA was isolated and microarray analysis was performed using an Illumina miRNA expression panel. RESULTS: A total of 526 miRNAs were identified. Out of those, 216 miRNAs were differentially regulated (p<0.05) between the comparison groups. As compared to the day of retrieval, 19, 11 and 6 miRNAs were differentially regulated more than 2 fold in the groups of no support, in the P support only, and in the P+E support respectively, 3-5 days after retrieval. During the peri-implantation period (3-5 days after retrieval) the expression of 33 and 6 miRNAs increased, while the expression of 3 and 0 miRNAs decreased, in the P alone and in the P+E group respectively as compared to the no steroid supplementation group. CONCLUSION: Luteal support following COS has a profound influence on miRNA profiles. Up or down regulation of miRNAs after P or P+E support suggest a role(s) of luteal support in the peri-implantation uterus in IVF cycles through the regulation of associated target genes. 相似文献
92.
The alternative pathway in cucumber seedlings under low temperature stress was enhanced by salicylic acid 总被引:1,自引:0,他引:1
Tao Lei Hong Feng Xin Sun Qi-Lin Dai Fan Zhang Hou-Guo Liang Hong-Hui Lin 《Plant Growth Regulation》2010,60(1):35-42
The alternative pathway is a cyanide-resistant and non-phosphorylatory electron transport pathway in mitochondria of higher
plants. Alternative oxidase (AOX) is the terminal oxidase of this pathway. Our present study investigated the effect of exogenous
salicylic acid (SA) on alternative pathway in cucumber (Cucumis sativus L.) seedlings under low temperature stress. Results showed that during the process of low temperature stress, the alternative
pathway capacity was enhanced as AOX expression increased in SA pretreated seedlings. Compared with seedlings without SA pretreatment,
slower decrease of relative water content and lower levels of electrolyte leakage, H2O2 and malonyldialdehyde content were detected in SA pretreated seedlings. These results indicated that SA could alleviate the
injury caused by low temperature on cucumber seedlings. Since the special protective functions of alternative pathway and
AOX in plants, we suggested that the alternative pathway was related to SA-mediated plant resistance to environmental stresses
such as low temperature. 相似文献
93.
94.
FANCJ/BRIP1 encodes a helicase that has been implicated in the maintenance of genomic stability. Here, to better understand
FANCJ function in DNA damage responses, we have examined the regulation of its cellular localization. FANCJ nuclear foci assemble
spontaneously during S phase and are induced by various stresses. FANCJ foci colocalize with the replication fork following
treatment with hydroxyurea, but not spontaneously. Using FANCJ mutants, we find that FANCJ helicase activity and the capacity
to bind BRCA1 are both involved in FANCJ recruitment. Given similarities to the recruitment of another Fanconi anemia protein,
FANCD2, we tested for colocalization of FANCJ and FANCD2. Importantly, these proteins show substantial colocalization, and
FANCJ promotes the assembly of FANCD2 nuclear foci. This process is linked to the proper localization of FANCJ itself since
both FANCJ and FANCD2 nuclear foci are compromised by FANCJ mutants that abrogate its helicase activity or interaction with
BRCA1. Our results suggest that FANCJ is recruited in response to replication stress and that FANCJ/BRIP1 may serve to link
FANCD2 to BRCA1. 相似文献
95.
Wei Fan Stefan A. W. Bouwense Ross Crawford Yin Xiao 《Journal of molecular histology》2010,41(1):51-60
Despite the important physiological role of periosteum in the pathogenesis and treatment of osteoporosis, little is known
about the structural and cellular characteristics of periosteum in osteoporosis. To study the structural and cellular differences
in both diaphyseal and metaphyseal periosteum of osteoporotic rats, samples from the right femur of osteoporotic and normal
female Lewis rats were collected and tissue sections were stained with hematoxylin and eosin, antibodies or staining kit against
tartrate resistant acid phosphatase (TRAP), alkaline phosphatase (ALP), vascular endothelial growth factor (VEGF), von Willebrand
(vWF), tyrosine hydroxylase (TH) and calcitonin gene-related peptide (CGRP). The results showed that the osteoporotic rats
had much thicker and more cellular cambial layer of metaphyseal periosteum compared with other periosteal areas and normal
rats (P < 0.001). The number of TRAP+ osteoclasts in bone resorption pits, VEGF+ cells and the degree of vascularization were found to be greater in the cambial layer of metaphyseal periosteum of osteoporotic
rats (P < 0.05), while no significant difference was detected in the number of ALP+ cells between the two groups. Sympathetic nerve fibers identified by TH staining were predominantly located in the cambial
layer of metaphyseal periosteum of osteoporotic rats. No obvious difference in the expression of CGRP between the two groups
was found. In conclusion, periosteum may play an important role in the cortical bone resorption in osteoporotic rats and this
pathological process may be regulated by the sympathetic nervous system. 相似文献
96.
Available resources could influence the trade-offs among different reproductive components in plants. Here, we created three nutrient levels to test the nutrient effects on trade-offs among sexual reproduction, clonal propagation and vegetative growth in a monoecious clonal herb Sagittaria pygmaea. The results of this study showed that the plant exhibited different trade-off patterns among different nutrient levels. When the nutrient level was low, there were weak trade-offs between sexual reproduction and vegetative growth and between clonal propagation and vegetative growth; when the nutrient level was moderate, we found a strong trade-off between sexual reproduction and clonal propagation; but when the nutrient level was high, we found no trade-offs among these three different reproductive components. These results indicated that the plant could adjust its trade-off patterns to fit the nutrient variation and suggested that trade-offs are unlikely to constrain the evolution of reproductive strategy in this species. 相似文献
97.
Xin Li Chun-Shan Quan Hui-Ying Yu Jian-Hua Wang Sheng-Di Fan 《World journal of microbiology & biotechnology》2009,25(1):151-154
A novel compound CF66I produced by Burkholeria cepacia was investigated for its antifungal effects against Fusarium solani by three different fluorescent dyes. Dual staining with propidium iodide (PI) and fluorescein diacetate (FDA) demonstrated
high doses of CF66I (120.0 μg ml−1) killed the fungi by acting primarily on the cell membrane. However, at fungistatic concentration (20.0 μg ml−1) of this compound, microscopic observations revealed swelling hyphae with abnormal chitin deposition, as determined by Calcofluor
white (CFW) staining, which was indicative of the alterations in cell wall structure. In addition, inhibition of intracellular
esterases activity was observed. These results led us to conclude that low doses of CF66I probably inhibited the fungal growth
by interfering with the cell metabolic pathways. 相似文献
98.
99.
Li JM Fan LM Shah A Brooks G 《American journal of physiology. Heart and circulatory physiology》2003,285(3):H1123-H1131
TGF-beta1 levels increase after vascular injury and promote vascular smooth muscle cell (VSMC) proliferation. We define a nonviral gene delivery system that targets alphavbeta3 and alpha5beta1 integrins that are expressed on proliferating VSMCs and strongly induced by TGF-beta1. A 15-amino acid RGDNP-containing peptide from American Pit Viper venom was linked to a Lys(16) peptide as vector (molossin vector) and complexed with Lipofectamine or fusogenic peptide for delivery of luciferase or beta-galactosidase reporter genes to primary cultures of human, rabbit, and rat VSMCs. Preincubation of VSMCs with TGF-beta1 for 24 h, but not with PDGF-BB, interferon-gamma, TNF-alpha, nor PMA, increased alphavbeta3 and alpha5beta1 expressions on VSMCs and enhanced gene delivery of molossin vector. Thus beta-galactosidase activity increased from 35 +/- 5% (controls) to 75 +/- 5% after TGF-beta1 treatment, and luciferase activity increased fourfold over control values. Potential use of this system in vessel bypass surgery was examined in an ex vivo rat aortic organ culture model after endothelial damage. Molossin vector system delivered beta-galactosidase to VSMCs in the vessel wall that remained for up to 12 days posttransfection. The molossin vector system, when combined with TGF-beta1, enhances gene delivery to proliferating VSMCs and might have clinical applications for certain vasculoproliferative diseases. 相似文献