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91.
92.
This paper reviews the recent studies that led to the conclusion that the noradrenergic neurons projecting to the medial preoptic area (mPOA) are hypnogenic and that they mediate this action through α1 adrenergic receptors. Microinjection of noradrenaline (NA) into the mPOA induced arousal. Studies using α2 adrenergic drugs showed that the arousal induced by intrapreoptic injection of NA was due to its action on presynaptic α2 adrenergic receptors. A combination of lesion and chemical stimulation techniques demonstrated that when NA acted on the postsynaptic α1 receptors in the mPOA, it induced sleep. Intrapreoptic injection of α1 agonist, methoxamine could induce sleep, when the hypothermia, which was simultaneously produced, was behaviorally compensated for by the animal. Increased arousal produced by the destruction of noradrenergic fibers in the mPOA further confirmed the hypnogenic role of these fibers. 相似文献
93.
New quantitative trait loci that regulate wound healing in an intercross progeny from DBA/1J and 129×1/SvJ inbred strains of mice 总被引:1,自引:0,他引:1
Masinde GL Li R Nguyen B Yu H Srivastava AK Edderkaoui B Wergedal JE Baylink DJ Mohan S 《Functional & integrative genomics》2006,6(2):157-163
Wound healing/regeneration mouse models are few, and studies performed have mainly utilized crosses between MRL/MPJ (a good
healer) and SJL/J (a poor healer) or MRL/lpr (a good healer) and C57BL/6J (a poor healer). Wound healing is a complex trait
with many genes involved in the expression of the phenotype. Based on data from previous studies that common and additional
quantitative trait loci (QTL) were identified using different crosses of inbred strains of mice for various complex traits,
we hypothesized that a new cross would identify common and additional QTL, unique modes of inheritance, and interacting loci,
which are responsible for variation in susceptibility to fast wound healing. In this study, we crossed DBA/1J (DBA, a good
healer) and 129/SvJ (129, a poor healer) and performed a genome-wide scan using 492 (DBA×129) F2 mice and 98 markers to identify
QTL that regulate wound healing/regeneration. Four QTL on chromosomes 1, 4, 12, and 18 were identified which contributed toward
wound healing in F2 mice and accounted for 17.1% of the phenotypic variation in ear punch healing. Surprisingly, locus interactions
contributed to 55.7% of the phenotype variation in ear punch healing. In conclusion, we have identified novel QTL and shown
that minor interacting loci contribute significantly to wound healing in DBA×129 mice cross.
The authors Masinde, Li, and Nguyen contributed equally to this article. 相似文献
94.
Single nucleotide RNA choreography 总被引:1,自引:1,他引:0
New structural analysis methods, and a tree formalism re-define and expand the RNA motif concept, unifying what previously appeared to be disparate groups of structures. We find RNA tetraloops at high frequencies, in new contexts, with unexpected lengths, and in novel topologies. The results, with broad implications for RNA structure in general, show that even at this most elementary level of organization, RNA tolerates astounding variation in conformation, length, sequence and context. However the variation is not random; it is well-described by four distinct modes, which are 3-2 switches (backbone topology variations), insertions, deletions and strand clips. 相似文献
95.
Der Sarkissian S Huentelman MJ Stewart J Katovich MJ Raizada MK 《Progress in biophysics and molecular biology》2006,91(1-2):163-198
Hypertension afflicts over 65 million Americans and poses an increased risk for cardiovascular morbidity such as stroke, myocardial infarction and end-stage renal disease resulting in significant mortality. Overactivity of the renin-angiotensin system (RAS) has been identified as an important determinant that is implicated in the etiology of these diseases and therefore represents a major target for therapy. In spite of the successes of drugs inhibiting various elements of the RAS, the incidence of hypertension and cardiovascular diseases remain steadily on the rise. This has lead many investigators to seek novel and innovative approaches, taking advantage of new pathways and technologies, for the control and possibly the cure of hypertension and related pathologies. The main objective of this review is to forward the concept that gene therapy and the genetic targeting of the RAS is the future avenue for the successful control and treatment of hypertension and cardiovascular diseases. We will present argument that genetic targeting of angiotensin-converting enzyme 2 (ACE2), a newly discovered member of the RAS, is ideally poised for this purpose. This will be accomplished by discussion of the following: (i) summary of our current understanding of the RAS with a focus on the systemic versus tissue counterparts as they relate to hypertension and other cardiovascular pathologies; (ii) the newly discovered ACE2 enzyme with its physiological and pathophysiological implications; (iii) summary of the current antihypertensive pharmacotherapy and its limitations; (iv) the discovery and design of ACE inhibitors; (v) the emerging concepts for ACE2 drug design; (vi) the current status of genetic targeting of the RAS; (vii) the potential of ACE2 as a therapeutic target for hypertension and cardiovascular disease treatment; and (viii) future perspectives for the treatment of cardiovascular diseases. 相似文献
96.
Reduction of vitrification in in vitro raised shoots derived from shoot bases and immature floral buds along with inflorescence axis used as explants of C. borivilianum, a rare medicinal herb is described. Shoot multiplication was obtained on MS medium with 2 mg l(-1) benzylaminopurine (BAP) + 0.1 mg l(-1) indole-3-butyric acid (IBA) and MS medium with 2 mg l(-1) kinetin (Kin) + 0.1 mg l(-1) 2,4-dichlorophenoxy acetic acid (2,4-D) from shoot bases and inflorescence axis respectively. Best multiplication rates were obtained from both the explants on MS medium with 2 mg l(-1) BAP. Vitrification of shoots in cultures appeared during the multiplication stage. Culture bottles with aerated caps reduced the vitrification to 80%. Reduction of BAP concentration from 2 mg l(-1) to zero during subsequent subcultures also minimized vitrification. Use of 0.5-2 mg l(-1) Kin produced healthy shoots when compared to BAP. In vitro raised shoots rooted on Knop salts containing iron and vitamins of MS medium, 2 mg l(-1) IBA and 0.1% activated charcoal. About 80% plantlets survived upon soil transfer. Scanning electron microscopic and image analyzer studies reveal the morphological structural differences between the leaves of normal and vitrified plantlets. 相似文献
97.
The cytotoxic fimbrial structural subunit of Xenorhabdus nematophila is a pore-forming toxin 下载免费PDF全文
We have purified a fimbrial shaft protein (MrxA) of Xenorhabdus nematophila. The soluble monomeric protein lysed larval hemocytes of Helicoverpa armigera. Osmotic protection of the cells with polyethylene glycol suggested that the 17-kDa MrxA subunit makes pores in the target cell membrane. The internal diameter of the pores was estimated to be >2.9 nm. Electron microscopy confirmed the formation of pores by the fimbrial subunit. MrxA protein oligomerized in the presence of liposomes. Electrophysiological studies demonstrated that MrxA formed large, voltage-gated passive-diffusion channels in lipid bilayers. 相似文献
98.
We have previously established mouse genetic models and identified the genetic components of quantitative trait loci (QTL)
on mouse chromosomes that contribute to phenotypes such as bone size, bone density, and bone's anabolic response to mechanical
loading. However, these regions contain dozens of unknown genes that are needed for functional testing. In this study, we
provided a protocol of nucleoporation with high efficiency by using a commercial nucleofection buffer and Gene Pulser to deliver
a test gene into bone cells for functional studies. We cloned an osteoblast differentiation-specific geneosterix (Osx) from a mouse bone cDNA library into a pHGCX expression vector and used nucleoporation to deliver pHGCX/Flag-Osx into the
nuclei of MC3T3-E1 cells. We then examined the transfection efficiency transgene expression, and function. Our results have
demonstrated that nucleoporation can deliver a transgene into MC3T3-E1 osteoblast cells with approx 94% transfection efficiency,
and express a functional Flag-Osx fusion protein capable of inducing cell differentiation as measured by an incease in alkaline
phosphatase (ALP) activity. Therefore, this experimental system provides a rapid, safe, and efficient cell-based model of
high-throughput phenotypic screening to identify candidate genes from physically mapped regions that are important for osteoblast
differentiation. 相似文献
99.
Ismail Thanseem Kumarasamy Thangaraj Gyaneshwer Chaubey Vijay Kumar Singh Lakkakula VKS Bhaskar B Mohan Reddy Alla G Reddy Lalji Singh 《BMC genetics》2006,7(1):1-11
Background
Past work on asthmatic African American families revealed a strong linkage peak with modest evidence of association on chromosome 11q. Here, we perform tests of association for asthma and a panel of 609 SNPs in African American subjects using a sliding window approach. While efficient in screening a region of dense genotyping, this approach does create some problems: high numbers of tests, assimilating thousands of results, and questions about setting priorities on regions with association signals.Results
We present a newly developed tool, Graphical Assessment of Sliding P-values or GrASP, which uses color display to indicate the width of the sliding windows, significance of individual tests, density of SNP coverage and location of known genes that simplifies some of these issues, and use it to identify regions of interest in these data.Conclusion
We demonstrate that GrASP makes it easier to visualize, summarize and prioritize regions of interest from sliding window haplotype analysis, based jointly on the p-value from all the tests from these windows and the building of haplotypes of significance in the region. Using this approach, five regions yielded strong evidence for linkage and association with asthma, including the prior peak linkage region. 相似文献100.
P Minakshi R Singh K Ranjan P Kumar CG Joshi YK Reddy G Prasad 《Journal of virology》2012,86(15):8337-8338
In this article, we document the first complete genome sequence of an isolate of bluetongue virus serotype 16 (BTV16) from a goat in India. The virus was isolated from an in-contact goat from an animal farm in Chennai where clinical disease occurs in sheep. The total size of the genome is 19,185 bp. The information provided for full-length sequences of all 10 segments will help in understanding the geographical origin and transmission of the Indian isolate of BTV16 as well as its comparison with global isolates of BTV16 of sheep, cattle, and other host species origins. 相似文献