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41.
We report the molecular cloning and characterization of the first leukocyte-associated Ig-like receptor 1 (LAIR-1) homologue in mice that we have named mouse LAIR-1 (mLAIR-1). The mLAIR-1 gene maps to the proximal end of mouse chromosome 7 in a region syntenic with human chromosome 19q13.4 where the leukocyte receptor cluster is located. The protein shares 40% sequence identity with human LAIR-1, has a single Ig-like domain, and contains two immunoreceptor tyrosine-based inhibitory motif-like structures in its cytoplasmic tail. Mouse LAIR-1 is broadly expressed on various immune cells, and cross-linking of the molecule on stably transfected RBL-2H3 and YT.2C2 cells results in strong inhibition of their degranulation and cytotoxic activities, respectively. Upon pervanadate stimulation, the mLAIR-1 cytoplasmic tail becomes phosphorylated, thereby recruiting Src homology region 2-containing tyrosine phosphatase-2. Interestingly, unlike human LAIR-1, Src homology region 2-containing tyrosine phosphatase-1 is not recruited to the mLAIR-1 cytoplasmic tail. Screening human and mouse cell lines for mLAIR-1 and human LAIR-1 binding partners identified several lines expressing putative ligand(s) for both receptors.  相似文献   
42.
Summary The postembryonic development of the antennal lobes of Periplaneta americana L. was examined with light- and electron-microscopical methods. There is no difference in the number of glomeruli and neurons in the antennal lobes of larval and adult animals. At hatching, the first larva already possesses the adult number of approximately 125 glomeruli and 500 to 560 deutocerebral neurons in the dorsolateral cell group of each antennal lobe. During postembryonic development the volume of the deutocerebral neurons increases three- to fourfold. The glomeruli of the first larva have about 7 % of the volume of the corresponding adult glomeruli. Since number, pattern, and size ratio of glomeruli (with the exception of the macroglomerulus) are constant in all larval stages and adult animals, it is possible to identify individual glomeruli. During the whole postembryonic development the ordinary glomeruli show a continuous volume increase, which parallels the increase in antennal sensory input. The macroglomerulus develops by way of special growth of two to four neuropil units, but not before the last three to four larval stages and only in males. Its growth precedes the formation of antennal pheromone receptors during the final molt; these receptors are known to project into the macroglomerulus. The development of the macroglomerulus in the last larval stages of the male may be caused by a genetically fixed growth program of specific deutocerebral neurons.Supported by the Deutsche Forschungsgemeinschaft (Scha 291/1)  相似文献   
43.

Background

Metamizole is used to treat pain in many parts of the world. Information on the safety profile of metamizole is scarce; no conclusive summary of the literature exists.

Objective

To determine whether metamizole is clinically safe compared to placebo and other analgesics.

Methods

We searched CENTRAL, MEDLINE, EMBASE, CINAHL, and several clinical trial registries. We screened the reference lists of included trials and previous systematic reviews. We included randomized controlled trials that compared the effects of metamizole, administered to adults in any form and for any indication, to other analgesics or to placebo. Two authors extracted data regarding trial design and size, indications for pain medication, patient characteristics, treatment regimens, and methodological characteristics. Adverse events (AEs), serious adverse events (SAEs), and dropouts were assessed. We conducted separate meta-analyses for each metamizole comparator, using standard inverse-variance random effects meta-analysis to pool the estimates across trials, reported as risk ratios (RRs). We calculated the DerSimonian and Laird variance estimate T2 to measure heterogeneity between trials. The pre-specified primary end point was any AE during the trial period.

Results

Of the 696 potentially eligible trials, 79 trials including almost 4000 patients with short-term metamizole use of less than two weeks met our inclusion criteria. Fewer AEs were reported for metamizole compared to opioids, RR = 0.79 (confidence interval 0.79 to 0.96). We found no differences between metamizole and placebo, paracetamol and NSAIDs. Only a few SAEs were reported, with no difference between metamizole and other analgesics. No agranulocytosis or deaths were reported. Our results were limited by the mediocre overall quality of the reports.

Conclusion

For short-term use in the hospital setting, metamizole seems to be a safe choice when compared to other widely used analgesics. High-quality, adequately sized trials assessing the intermediate- and long-term safety of metamizole are needed.  相似文献   
44.
The bloody clam, Tegillarca granosa, is a commercial benthic bivalve, having a strong accumulation ability and torrelence to cadmium. To investigate whether vitellogenin (Vg) is involved in cadmium (Cd) detoxification, the full-length cDNA of T. granosa Vg was cloned, and its expression pattern in response to cadmium exposure was studied compared with the reference metallothionein (MT) gene. The full T. granosa Vg sequence consisted of 8988 bp, including a 6930-bp open reading frame that encoded a 2309 amino acid polypeptide. The deduced Vg protein contained a Vg N-terminal domain, domain of unknown function (DUF1943), SbcC domain, and von Willebrand factor type D domain (VWD). Multiple metal-binding sites were predicted in the deduced T. granosa Vg protein, suggesting its potential in functioning as a metal-binding protein. In addition, Vg expression increased in the T. granosa digestive gland and hemolymph in time-dependent manner after exposure to 1, 3, 6 and 9 μg/L Cd for 28 days. MT expression was measured in parallel with Vg expression, and the latter was more sensitive to Cd induction than the former. Together, results of the present research suggested that Vg may play an important role in T. granosa metal detoxification.  相似文献   
45.
Tumor progression is controlled by signals from cellular and extra-cellular microenvironment including stromal cells and the extracellular matrix. Consequently, three-dimensional in vitro tumor models are essential to study the interaction of tumor cells with their microenvironment appropriately in a biologically relevant manner. We have previously used organotypic co-cultures to analyze the malignant growth of human squamous cell carcinoma (SCC) cell lines on a stromal equivalent in vitro. In this model, SCC cell lines are grown on a collagen-I gel containing fibroblasts. Since macrophages play a critical role in the progression of many tumor types, we now have expanded this model by integrating macrophages into the collagen gel of these organotypic tumor co-cultures. This model was established as a murine and a human system of skin SCCs. The effect of macrophages on tumor progression depends on their polarization. We demonstrate that macrophage polarization in organotypic co-cultures can be modulated towards and M1 or an M2 phenotype by adding recombinant IFN-γ and LPS or IL-4 respectively to the growth medium. IL-4 stimulation of macrophage-containing cultures resulted in enhanced tumor cell invasion evidenced by degradation of the basement membrane, enhanced collagenolytic activity and increased MMP-2 and MMP-9. Interestingly, extended co-culture with tumor cells for three weeks resulted in spontaneous M2 polarization of macrophages without IL-4 treatment. Thus, we demonstrate that macrophages can be successfully integrated into organotypic co-cultures of murine or human skin SCCs and that this model can be exploited to analyze macrophage activation towards a tumor supporting phenotype.  相似文献   
46.
Predentin(e) was dissected out from unerupted permanent bovine teeth. The non-collagenous proteins were extracted at -13 degrees C by 4 M-guanidinium chloride containing proteinase inhibitors and separated by DEAE-Sepharose and Sephadex G-100 chromatography. In addition to a few minor constituents, the only major non-collagenous components that could be demonstrated were albumin and proteoglycan. The localization of the former, demonstrated by optical-microscopical immunochemistry, was such that it was concluded that albumin is not a constituent of predentin matrix. Very low amounts of phosphoprotein were found in predentin matrix. This was of two types, high- and low-phosphorylated. Larger amounts of phosphoprotein were not present until the dissection was carried deeper into newly formed dentin(e). On the basis of the present results and previously obtained morphological data the conclusion was drawn that predentin matrix, containing virtually only collagen type I and proteoglycan, is similar in composition to that of loose connective tissue and primarily aimed at the production and maturation of collagen fibres. Only immediately before the mineralization front are the non-collagenous protein components secreted that initiate and govern calcium-phosphate mineral formation.  相似文献   
47.
Fifteen restriction sites were mapped to the 28S ribosomal RNA gene of individuals representing 54 species of frogs, two species of salamanders, a caecilian, and a lungfish. Eight of these sites were present in all species examined, and two were found in all but one species. Alignment of these conserved restriction sites revealed, among anuran 28S rRNA genes, five regions of major length variation that correspond to four of 12 previously identified divergent domains of this gene. One of the divergent domains (DD8) consists of two regions of length variation separated by a short segment that is conserved at least throughout tetrapods. Most of the insertions, deletions, and restriction-site variations identified in the 28S gene will require sequence-level analysis for a detailed reconstruction of their history. However, an insertion in DD9 that is coextensive with frogs in the suborder Neobatrachia, a BstEII site that is limited to representatives of two leptodactylid subfamilies, and a deletion in DD10 that is found only in three ranoid genera are probably synapomorphies.   相似文献   
48.
The genus Rosa has a complex evolutionary history caused by several factors, often in conjunction: extensive hybridization, recent radiation, incomplete lineage sorting, and multiple events of polyploidy. We examined the applicability of AFLP markers for reconstructing (species) relationships in Rosa, using UPGMA clustering, Wagner parsimony, and Bayesian inference. All trees were well resolved, but many of the deeper branches were weakly supported. The cluster analysis showed that the rose cultivars can be separated into a European and an Oriental cluster, each being related to different wild species. The phylogenetic analyses showed that (1) two of the four subgenera (Hulthemia and Platyrhodon) do not deserve subgeneric status; (2) section Carolinae should be merged with sect. Cinnamomeae; (3) subsection Rubigineae is a monophyletic group within sect. Caninae, making sect. Caninae paraphyletic; and (4) there is little support for the distinction of the five other subsections within sect. Caninae. Comparison of the trees with morphological classifications and with previous molecular studies showed that all methods yielded reliable trees. Bayesian inference proved to be a useful alternative to parsimony analysis of AFLP data. Because of their genome-wide sampling, AFLPs are the markers of choice to reconstruct (species) relationships in evolutionary complex groups.  相似文献   
49.
短柄五加开花及传粉生物学研究   总被引:15,自引:0,他引:15  
本文对短柄五加(Eleutherococcusbrachypus)的花期物候、开花式样、访花昆虫种类、访花行为及访花频率进行了观察,对花粉活力、柱头可授性、花粉胚珠比以及传粉效果和繁育系统做了检测。初步结果表明,短柄五加以根茎进行无性繁殖,1个居群为1个无性系。虽自交亲和,但昆虫的访花活动可显著提高座果率。昆虫传粉主要在无性系内异花间进行,属于广义的自花传粉。传粉者为多种不同的昆虫,包括马蜂和胡蜂在内的蜂类、蝇类和甲虫。其花期物候、花粉活力、柱头可授期和蜜汁分泌期等特征使其能够适应环境,从而获得较高的座果率。平均座果率为65%,饱满种子率为45.5%。自然条件下未发现实生苗,广义的自花传粉导致的种子质量低下可能是其原因,也是限制短柄五加分布范围的重要因素。  相似文献   
50.
Force development in smooth muscle, as in skeletal muscle, is believed to reflect recruitment of force-generating myosin cross-bridges. However, little is known about the events underlying cross-bridge recruitment as the muscle cell approaches peak isometric force and then enters a period of tension maintenance. In the present studies on single smooth muscle cells isolated from the toad (Bufo marinus) stomach muscularis, active muscle stiffness, calculated from the force response to small sinusoidal length changes (0.5% cell length, 250 Hz), was utilized to estimate the relative number of attached cross-bridges. By comparing stiffness during initial force development to stiffness during force redevelopment immediately after a quick release imposed at peak force, we propose that the instantaneous active stiffness of the cell reflects both a linearly elastic cross-bridge element having 1.5 times the compliance of the cross-bridge in frog skeletal muscle and a series elastic component having an exponential length-force relationship. At the onset of force development, the ratio of stiffness to force was 2.5 times greater than at peak isometric force. These data suggest that, upon activation, cross-bridges attach in at least two states (i.e., low-force-producing and high-force-producing) and redistribute to a steady state distribution at peak isometric force. The possibility that the cross-bridge cycling rate was modulated with time was also investigated by analyzing the time course of tension recovery to small, rapid step length changes (0.5% cell length in 2.5 ms) imposed during initial force development, at peak force, and after 15 s of tension maintenance. The rate of tension recovery slowed continuously throughout force development following activation and slowed further as force was maintained. Our results suggest that the kinetics of force production in smooth muscle may involve a redistribution of cross-bridge populations between two attached states and that the average cycling rate of these cross-bridges becomes slower with time during contraction.  相似文献   
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