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141.
Marja Laasonen Laura Hokkanen Sami Leppmki Pekka Tani Arja T. Erkkil 《Prostaglandins, leukotrienes, and essential fatty acids》2009,81(1):89-96
In project DyAdd, we compared the fatty acid (FA) profiles of serum phospholipids in adults with attention deficit hyperactivity disorder (ADHD) (n=26), dyslexia (n=36), their comorbid combination (n=9), and healthy controls (n=36). FA proportions were analyzed in a 2×2 design with Bonferroni corrected post hoc comparisons. A questionnaire was used to assess dietary fat quality and use of supplements. Results showed that ADHD and dyslexia were not associated with total saturated FAs, monounsaturated FAs, or n-3 polyunsaturated FAs (PUFAs). However, those with ADHD had elevated proportions of total n-6 PUFAs (including γ-linolenic and adrenic acids) as compared to those without ADHD. Dyslexia was related to a higher proportion of monounsaturated nervonic acid and a higher ratio of n-6/n-3 PUFAs. Among females none of the associations were significant. However in males, all the original associations observed in all subjects remained and ADHD was associated with elevated nervonic acid and n-6/n-3 PUFA ratio like dyslexia. Controlling for poorly diagnosed reading difficulties, education, dietary fat quality, or use of FA supplements did not generally remove the originally observed associations. 相似文献
142.
Jing Chen Sun Er Hui Zhang Lun Guang Yao Hong Ling Zhang Peng Fei Jin 《Biotechnology progress》2009,25(2):524-529
A high efficient way for generation of recombinant Bombyx mori (silkworm) multiple nucleopolyhedrovirus by Tn7‐mediated transposition in Escherichia coli was performed. The new system consists of a conditional replication donor vector pRCDM and an attTn7 site blocked E. coli containing BmNPV‐Bacmid. The donor vector contains a replication origin derived from R6Kγ, which propagated only in host cells with pir gene expression decreased in the transposition background greatly. Compared with original vector derived from pUC, the transposition efficiency increased from 5.7 to 66% (≈10 fold) when using conditional replication vector pRCDM transposition into original BmDH10Bac. A further effort to decrease the transposition background was made by blocking the attTn7 site in host E. coli genome. The resulting attTn7 occupied BmDH10BacΔTn7 resulted in a significant increase from 5.7 to 23% (≈4 fold) in the efficacy of generate recombinant BmNPV Bacmid by transposition. Furthermore, the transposition of BmDH10BacΔTn7 with pRCDM resulted typically in 100% white colonies, and it indicated that a zero transposition background was accomplished. This high efficient and zero background transposition system provides a new simple and rapid method for construction of recombinant BmNPV used to express target genes or produce gene‐delivery virus particles in silkworm. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
143.
144.
Early succession of bacterial biofilms in paper machines 总被引:1,自引:0,他引:1
Marja Tiirola Tomi Lahtinen Matti Vuento Christian Oker-Blom 《Journal of industrial microbiology & biotechnology》2009,36(7):929-937
Formation of biofilms causes severe problems in paper machines, and hence financial costs. It would be preferable to prevent
attachment of the primary-colonizing bacteria than to control the growth of secondary communities, which are sheltered by
exopolysaccharide slime layers. We have therefore investigated the early succession of paper-machine biofilms by incubating
stainless-steel test coupons in the process water-flow lines in two paper machines operating in slightly alkaline conditions
in temperatures (45 and 49°C) supporting thermophilic microbes. Microbial succession was profiled using length heterogeneity
analysis of PCR-amplified 16S rRNA genes (LH-PCR) and linking the sequence data of the created 16S rRNA gene libraries to
the dominant LH-PCR peaks. Although the bacterial fingerprints obtained from the attached surface communities varied slightly
in different samples, the biomarker signals of the dominating primary-colonizing bacterial groups remained high over time
in each paper machine. Most of the 16S rRNA gene copies in the early biofilms were assigned to the genera Rhodobacter, Tepidimonas, and Cloacibacterium. The dominance of these sequence types decreased in the developing biofilms. Finally, as phylogenetically identical primary-colonizers
were detected in the two different paper mills, the machines evidently had similar environmental conditions for bacterial
growth and potentially a common source of contamination. 相似文献
145.
So far very few experiments have accounted for the combined effect of two phenomena co-occurring in stress gradients: local
adaptation to stress and the increase in facilitation with increasing stress (predicted by the stress-gradient hypothesis,
SGH). Mountain birch (Betula pubescens subsp. czerepanovii) facilitates conspecific seedlings in subarctic high stress sites and is capable of rapid evolutionary adaptation, being
therefore a good model species for a study combining local ecotypes and SGH. A within-species experiment was conducted to
test SGH in three stress gradients, detect potential local adaptations between low and high stress populations, and assess
their effects on seedling-seedling interactions. Although no evidence for local adaptation was detected, high and low stress
populations showed some differentiation, possibly explained by decreasing phenotypic plasticity in high stress conditions
and/or neutral evolutionary mechanisms. Weak support for SGH was detected. While facilitation was unaffected by seedling origin,
low stress populations showed better competitive ability. 相似文献
146.
Lysosomal involvement in cell death and cancer 总被引:1,自引:0,他引:1
Lysosomes, with their arsenal of degradative enzymes are increasingly becoming an area of interest in the field of oncology. The changes induced in this compartment upon transformation are numerous and whereas most are viewed as pro-oncogenic the same processes also render cancer cells susceptible to lysosomal death pathways. This review will provide an overview of the pro- and anti-oncogenic potential of this compartment and how these might be exploited for cancer therapy, with special focus on lysosomal death pathways. 相似文献
147.
Chi‐Tai Chiang Wing‐Keung Chu Shu‐Er Chow Jan‐Kan Chen 《Journal of cellular physiology》2009,219(1):117-122
p63 belongs to a member of the tumor suppressor protein p53 family. Due to alternative promoter usage, two types of p63 proteins are produced. The ΔNp63 isoform lacks the N‐terminal transactivation domain and is thought to antagonize TAp63 and p53 in target gene regulation. ΔNp63 has been found to be overexpressed in numerous human squamous cell carcinomas, including nasopharyngeal carcinoma (NPC). However, the role of ΔNp63 overexpression in NPC pathogenesis has not been clear. In this study, we use a ΔNp63 overexpressing human NPC cell line (NPC‐076) to explore the possible roles of ΔNp63 in cell proliferation and cell‐cycle regulation. We found that the proliferation of NPC‐076 cell is greatly suppressed when the overexpressed ΔNp63 is silenced by specific ΔNp63 siRNA. Further studies show that ΔNp63 silencing results in the upregulation of CKIs, including p27kip1 and p57kip2 in both mRNA and protein levels. Cell‐cycle analysis shows that ΔNp63 silencing also results in an increased G1 phase cell and apoptotic cell population. Our findings indicate that ΔNp63 plays important roles in the regulation of NPC‐076 cell‐cycle progression, and may play a role in the maintenance of NPC‐076 tumor cell phenotype. J. Cell. Physiol. 219: 117–122, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
148.
Maria Giovanna Sabbieti Dimitrios Agas Liping Xiao Luigi Marchetti J. Douglas Coffin Thomas Doetschman Marja M. Hurley 《Journal of cellular physiology》2009,219(1):143-151
Parathyroid hormone (PTH) increases fibroblast growth factor receptor‐1 (FGFR1) and fibroblast growth factor‐2 (FGF‐2) expression in osteoblasts and the anabolic response to PTH is reduced in Fgf2?/? mice. This study examined whether candidate factors implicated in the anabolic response to PTH were modulated in Fgf2?/? osteoblasts. PTH increased Runx‐2 protein expression in Fgf2+/+ but not Fgf2?/? osteoblasts. By immunocytochemistry, PTH treatment induced nuclear accumulation of Runx‐2 only in Fgf2+/+ osteoblasts. PTH and FGF‐2 regulate Runx‐2 via activation of the cAMP response element binding proteins (CREBs). Western blot time course studies showed that PTH increased phospho‐CREB within 15 min that was sustained for 24 h in Fgf2+/+ but had no effect in Fgf2?/? osteoblasts. Silencing of FGF‐2 in Fgf2+/+ osteoblasts blocked the stimulatory effect of PTH on Runx‐2 and CREBs phosphorylation. Studies of the effects of PTH on proteins involved in osteoblast precursor proliferation and apoptosis showed that PTH increased cyclinD1‐cdk4/6 protein in Fgf2+/+ but not Fgf2?/? osteoblasts. Interestingly, PTH increased the cell cycle inhibitor p21/waf1 in Fgf2?/? osteoblasts. PTH increased Bcl‐2/Bax protein ratio in Fgf2+/+ but not Fgf2?/? osteoblasts. In addition PTH increased cell viability in Fgf2+/+ but not Fgf2?/? osteoblasts. These data suggest that endogenous FGF‐2 is important in PTH effects on osteoblast proliferation, differentiation, and apoptosis. Reduced expression of these factors may contribute to the reduced anabolic response to PTH in the Fgf2?/? mice. Our results strongly indicate that the anabolic PTH effect is dependent in part on FGF‐2 expression. J. Cell. Physiol. 219: 143–151, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
149.
Gabor Er?s Saleh Ibrahim Nikolai Siebert Mihály Boros Brigitte Vollmar 《Arthritis research & therapy》2009,11(2):R43
Introduction
Phosphatidylcholine and phosphatidylcholine-derived metabolites exhibit anti-inflammatory properties in various stress conditions. We hypothesized that dietary phosphatidylcholine may potentially function as an anti-inflammatory substance and may decrease inflammatory activation in a chronic murine model of rheumatoid arthritis (collagen-induced arthritis). 相似文献150.
Carla M. P. Cardoso Line Groth-Pedersen Maria H?yer-Hansen Thomas Kirkegaard Elizabeth Corcelle Jens S. Andersen Marja J??ttel? Jesper Nylandsted 《PloS one》2009,4(2)