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801.
The present study examines the use of buffalo preantral follicles as a source of oocytes for in vitro embryo production. Preantral follicles were isolated from abattoir-derived buffalo ovaries and were grown for 100 days in five different culture systems: (1) minimum essential medium (MEM); (2) coconut water; (3) MEM + ovarian mesenchymal cell (OMC) co-culture; (4) MEM + granulosa cell (GC) co-culture; or (5) MEM + cumulus cell (CC) co-culture. Low growth rates for the preantral follicles were observed when follicles were cultured in MEM or coconut water medium. Moderate growth rates were seen for OMC and GC co-cultures, and high rates of growth were observed when follicles were grown in CC co-culture. The survival of preantral follicles was low in the MEM culture (<25%), but was over 75% in the other culture systems. Oocytes were not recovered from the MEM group, while an oocyte recovery rate of 80-100% was observed when the follicles were cultured with coconut water/somatic cells. Transferable embryos could be produced only with the oocytes obtained from preantral follicles grown in the OMC and CC co-culture systems. This study demonstrates, for the first time, that it is possible to produce buffalo embryos by in vitro fertilization of oocytes derived from in vitro grown preantral follicles. 相似文献
802.
Omega-(2-Naphthyloxy) amino alkanes as a novel class of anti-hyperglycemic and lipid lowering agents
omega-(2-Naphthyloxy) amino alkanes, obtained as major by-product during course of synthesis of carbamate esters from omega-(2-naphthyloxy) alkyl halides and amines, showed significant anti-hyperglycemic and lipid lowering activities in various test models as a novel class of compounds. Compounds were tested in rat GLM, SLM, STZ, and STZ-S models at 100mg/kg dose. Of these compound 13 was found to be the most active which caused lowering of sugar by 33.6%, 31.0%, 28.5%, and 73.8% in GLM, SLM, STZ, STZ-S, and db/db mice models, respectively. It also significantly effected lowering of LDL in rat model and also in Hamster model without reducing HDL. Most of the compounds showing anti-diabetic and lipid lowering activity have shown promising PPAR-alpha/gamma/delta-activity. Compounds 6, 13, and 19 have shown very good PPAR-alpha/gamma/delta activity. 相似文献
803.
Sarkar P Sarkar S Ramesh V Kim H Barnes S Kulkarni A Hall JC Wilson BL Thomas RL Pellis NR Ramesh GT 《Neurochemical research》2008,33(11):2335-2341
Exposure to altered microgravity during space travel induces changes in the brain and these are reflected in many of the physical
behavior seen in the astronauts. The vulnerability of the brain to microgravity stress has been reviewed and reported. Identifying
microgravity-induced changes in the brain proteome may aid in understanding the impact of the microgravity environment on
brain function. In our previous study we have reported changes in specific proteins under simulated microgravity in the hippocampus
using proteomics approach. In the present study the profiling of the hypothalamus region in the brain was studied as a step
towards exploring the effect of microgravity in this region of the brain. Hypothalamus is the critical region in the brain
that strictly controls the pituitary gland that in turn is responsible for the secretion of important hormones. Here we report
a 2-dimensional gel electrophoretic analysis of the mouse hypothalamus in response to simulated microgravity. Lowered glutathione
and differences in abundance expression of seven proteins were detected in the hypothalamus of mice exposed to microgravity.
These changes included decreased superoxide dismutase-2 (SOD-2) and increased malate dehydrogenase and peroxiredoxin-6, reflecting
reduction of the antioxidant system in the hypothalamus. Taken together the results reported here indicate that oxidative
imbalance occurred in the hypothalamus in response to simulated microgravity. 相似文献
804.
Some naturally occurring strains of fungi cease growing through successive subculturing, i.e., they senesce. In Neurospora, senescing strains usually contain intramitochondrial linear or circular plasmids. An entire plasmid or its part(s) integrates into the mtDNA, causing insertional mutagenesis. The functionally defective mitochondria replicate faster than the wild-type mitochondria and spread through interconnected hyphal cells. Senescence could also be due to spontaneous lethal nuclear gene mutations arising in the multinucleated mycelium. However, their phenotypic effects remain masked until the nuclei segregate into a homokaryotic spore, and the spore germinates to form a mycelium that is incapable of extended culturing. Ultimately the growth of a fungal colony ceases due to dysfunctional oxidative phosphorylation. Results with senescing nuclear mutants or growth-impaired cytoplasmic mutants suggest that mtDNA is inherently unstable, requiring protection by as yet unidentified nuclear-gene-encoded factors for normal functioning. Interestingly, these results are in accord with the endosymbiotic theory of origin of eukaryotic cells. 相似文献
805.
806.
Narayanan R Coss CC Yepuru M Kearbey JD Miller DD Dalton JT 《Molecular endocrinology (Baltimore, Md.)》2008,22(11):2448-2465
Androgen receptor (AR) ligands are important for the development and function of several tissues and organs. However, the poor oral bioavailability, pharmacokinetic properties, and receptor cross-reactivity of testosterone, coupled with side effects, place limits on its clinical use. Selective AR modulators (SARMs) elicit anabolic effects in muscle and bone, sparing reproductive organs like the prostate. However, molecular mechanisms underlying the tissue selectivity remain ambiguous. We performed a variety of in vitro studies to compare and define the molecular mechanisms of an aryl propionamide SARM, S-22, as compared with dihydrotestosterone (DHT). Studies indicated that S-22 increased levator ani muscle weight but decreased the size of prostate in rats. Analysis of the upstream intracellular signaling events indicated that S-22 and DHT mediated their actions through distinct pathways. Modulation of these pathways altered the recruitment of AR and its cofactors to the PSA enhancer in a ligand-dependent fashion. In addition, S-22 induced Xenopus laevis oocyte maturation and rapid phosphorylation of several kinases, through pathways distinct from steroids. These studies reveal novel differences in the molecular mechanisms by which S-22, a nonsteroidal SARM, and DHT mediate their pharmacological effects. 相似文献
807.
Shweta B Maheshwari DK Dubey RC Arora DS Bajpai VK Kang SC 《Journal of microbiology and biotechnology》2008,18(9):1578-1583
Rhizobacteria are used as inoculants to enhance crop yield and for biological control of fungal pathogens. Fluorescent pseudomonads isolated from the rhizosphere of groundnut showed suppression of the phytopathogen Macrophomina phaseolina that causes charcoal rot of groundnut, an economically important agroproduct. Two strains of fluorescent pseudomonads, designated as PS1 and PS2, were selected as a result of in vitro antifungal activity. After 5 days of incubation at 28+/-1 degrees , both PS1 and PS2 caused clear inhibition zones in dual cultures, restricting the growth of M. phaseolina by 71% and 74%, respectively. Both the strains were capable of producing siderophores, indole acetic acid, and hydrocyanic acid, and causing phosphate solubilization under normal growth conditions. These strains, when used as inoculants in groundnut, enhanced germination up to 15% and 30% with subsequent increase in grain yield by 66% and 77%, respectively. Conversely, when the pathogen alone was testeds 57% decrease in yield was recorded. Thus the studies revealed the potential of the two pseudomonads not only as biocontrol agents against M. phaseolina, but also as a good growth promoter for groundnut. 相似文献
808.
A. Vasudevan N. Selvaraj A. Ganapathi S. Kasthurirengan V. Ramesh Anbazhagan M. Manickavasagam C. W. Choi 《In vitro cellular & developmental biology. Plant》2008,44(4):300-306
Enhanced numbers of multiple shoots were induced from shoot tip explants of cucumber. The effects of amino acids (leucine,
isoleucine, methionine, threonine, and tryptophan) and polyamines (spermidine, spermine, and putrescine) along with benzyladenine
(BA) on multiple shoot induction were investigated. A Murashige and Skoog (MS) medium containing a combination of BA (4.44 μM),
leucine (88 μM), and spermidine (68 μM) induced the maximum number of shoots (36.6 shoots per explant) compared to BA (4.44 μM)
alone or BA (4.44 μM) with leucine (88 μM). The regenerated shoots were elongated on the same medium. Elongated shoots were
transferred to the MS medium fortified with BA (4.44 μM), leucine (88 μM), and putrescine (62 μM) for root induction. Rooted
plants were hardened and successfully established in soil with a 90% survival rate. 相似文献
809.
Alireza Sadeghnejad Wilfried Karmaus S Hasan Arshad Ramesh Kurukulaaratchy Marianne Huebner Susan Ewart 《Respiratory research》2008,9(1):2
Background
Tobacco smoke and genetic susceptibility are risk factors for asthma and wheezing. The aim of this study was to investigate whether there is a combined effect of interleukin-13 gene (IL13) polymorphisms and tobacco smoke on persistent childhood wheezing and asthma.Methods
In the Isle of Wight birth cohort (UK, 1989–1999), five IL13 single nucleotide polymorphisms (SNPs): rs1800925 (-1112C/T), rs2066960, rs1295686, rs20541 (R130Q) and rs1295685 were genotyped. Parents were asked whether their children had wheezed in the last 12 months at ages 1, 2, 4 and 10 years. Children who reported wheeze in the first 4 years of life and also had wheezing at age 10 were classified as early-onset persistent wheeze phenotype; non-wheezers never wheezed up to age 10. Persistent asthma was defined as having a diagnosis of asthma both during the first four years of life and at age 10. Logistic regression methods were used to analyze data on 791 children with complete information. Potential confounders were gender, birth weight, duration of breast feeding, and household cat or dog present during pregnancy.Results
Maternal smoking during pregnancy was associated with early-onset persistent wheeze (OR 2.93, p < 0.0001); polymorphisms in IL13 were not (OR 1.15, p = 0.60 for the common haplotype pair). However, the effect of maternal smoking during pregnancy was stronger in children with the common IL13 haplotype pair compared to those without it (OR 5.58 and OR 1.29, respectively; p for interaction = 0.014). Single SNP analysis revealed a similar statistical significance for rs20541 (p for interaction = 0.02). Comparable results were observed for persistent childhood asthma (p for interaction = 0.03).Conclusion
This is the first report that shows a combined effect of in utero exposure to smoking and IL13 on asthma phenotypes in childhood. The results emphasize that genetic studies need to take environmental exposures into account, since they may explain contradictory findings. 相似文献810.
Prasad Suresh Hendre Regur Phanindranath V Annapurna Albert Lalremruata Ramesh K Aggarwal 《BMC plant biology》2008,8(1):51