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81.
An observational study of chamois behavior during the rut was conducted at the Los Angeles Zoo. The herd consisted of an adult male, two adult females, two subadult females, and two kids (1.1). During the 13-week study, observers collected scan data on all animals and recorded all occurrences of selected social behaviors during interactions which involved the adult male. Scan observations showed that open areas of the enclosure close to the public were the least preferred, and areas with good rest places were used most. Overall the herd spent 73% of their time stationary, 13% foraging/feeding, 6% moving, and less than 5% each in object investigation, maintenance, play, and social behavior. The adult male rested and fed less, and stood vigilant and engaged in social behavior more frequently than the others. Nearest neighbor data showed clear patterns of kin association beyond the mother-last kid bond. The adult male interacted most often with the regular keepers, the subordinate female and the oldest subadult female. Interactions with the females consisted mostly of herding and sexual behaviors, while those with keepers were almost exclusively competitive/aggressive. While most findings paralleled those from studies of wild chamois, no study has previously reported long-lasting associations among kin.  相似文献   
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Acupuncture is useful for functional bowel diseases, such as constipation and diarrhea. However, the mechanisms of beneficial effects of acupuncture on colonic function have scarcely ever been investigated. We tested the hypothesis that electroacupuncture (EA) at ST-36 stimulates colonic motility and transit via a parasympathetic pathway in conscious rats. Hook-shaped needles were inserted at bilateral ST-36 (lower limb) or BL-21 (back) and electrically stimulated at 10 Hz for 20 min. We also studied c-Fos expression in response to EA at ST-36 in Barrington's nucleus of the pons. EA at ST-36, but not BL-21, significantly increased the amplitude of motility at the distal colon. The calculated motility index of the distal colon increased to 132 +/- 9.9% of basal levels (n = 14, P < 0.05). In contrast, EA at ST-36 had no stimulatory effects in the proximal colon. EA at ST-36 significantly accelerated colonic transit [geometric center (GC) = 6.76 +/- 0.42, n = 9, P < 0.001] compared with EA at BL-21 (GC = 5.23 +/- 0.39, n = 7). The stimulatory effect of EA at ST-36 on colonic motility and transit was abolished by pretreatment with atropine. EA-induced acceleration of colonic transit was also abolished by extrinsic nerve denervation of the distal colon (GC = 4.69 +/- 0.33, n = 6). The number of c-Fos-immunopositive cells at Barrington's nucleus significantly increased in response to EA at ST-36 to 8.1 +/- 1.1 cells/section compared with that of controls (2.4 +/- 0.5 cells/section, n = 3, P < 0.01). It is concluded that EA at ST-36 stimulates distal colonic motility and accelerates colonic transit via a sacral parasympathetic efferent pathway (pelvic nerve). Barrington's nucleus plays an important role in mediating EA-induced distal colonic motility in conscious rats.  相似文献   
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Corticotropin releasing factor (CRF) is one of the most important factors in the mechanism of stress-induced stimulation of colonic motility. However, it is controversial whether stress-induced stimulation of colonic motility is mediated via central or peripheral CRF receptors. We investigated the hypothesis that peripherally injected CRF accelerates colonic motility through the central CRF receptor, but not the peripheral CRF receptor. A strain gauge transducer was sutured on the serosal surface of the proximal colon. Colonic motility was monitored before and after the peripheral injection of CRF. An in vitro muscle strip study was also performed to investigate the peripheral effects of CRF. Subcutaneous injection of CRF (30-100 microg/kg) stimulated colonic motility in a dose-dependent manner. The stimulatory effect of peripherally administered CRF on colonic motility was abolished by truncal vagotomy, hexamethonium, atropine, and intracisternal injection of astressin (a CRF receptor antagonist). No responses to CRF (10(-9) -10(-7) M) of the muscle strips of the proximal colon were observed. These results suggest that the stimulatory effect of colonic motility in response to peripheral administration of CRF is mediated by the vagus nerve, nicotinic receptors, muscarinic receptors, and CRF receptors of the brain stem. It is concluded that peripherally administered CRF reaches the area postrema and activates the dorsal nucleus of vagi via central CRF receptors, resulting in stimulation of the vagal efferent and cholinergic transmission of the proximal colon.  相似文献   
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Birds deposit the trace element selenium (Se) into their eggs because an adequate supply of this micronutrient is essential for embryonic development. Although there is considerable interest in egg Se with regard to topics as diverse as poultry nutrition and environmental pollution, data on the natural levels of Se in eggs of free-living avian species are currently very limited. To address this lack of information, we measured the yolk Se concentrations in eggs of 14 avian species collected in the wild. The concentrations (ng/g wet yolk) varied from 394 to 2238, with a mean value of 1040. Values (means+/-SD) for eggs from the UK, Canada and New Zealand were, respectively, 522+/-192 (3 species), 1194+/-584 (8 species) and 1147+/-200 (3 species). However, analysis by appropriate statistical models indicates that the effect of phylogenetic relatedness among these species is so significant that it removes any effect of geographical location. In particular, species belonging to the order Passeriformes displayed significantly higher yolk Se levels than Non-Passeriforme species. In marked contrast to the free-living species, our previously published data indicate that the Se concentration in egg yolk of the domestic chicken is only about 100 ng/g wet yolk when the birds are maintained on a basal commercial diet without supplementary Se. The results reveal an extensive interspecies variation in yolk Se (across a 6-fold range) for eggs collected from the wild. Nevertheless, the Se concentrations in the yolks of all the free-living species were far higher (4-21-fold) than that achieved in the yolk of the domestic chicken consuming a standard basal diet.  相似文献   
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The Brazilian savanna-like vegetation of Cerrado is rapidly being converted to pasture and agricultural fields. A 16S rDNA-based approach was taken to study the bacterial community associated with the soil of a native cerrado area (sensu stricto) and an area that has been converted to pasture. The bacterial group most abundantly identified in cerrado sensu stricto soil was the alpha-Proteobacteria while in cerrado converted to pasture the Actinobacteria were the most abundant. Rarefaction curves indicate that the species richness of cerrado sensu stricto is greater than that of cerrado converted to pasture. Furthermore, lineage-through-time plots show that the expected richness of species present in cerrado sensu stricto soil is approximately 10 times greater than that of cerrado converted to pasture.  相似文献   
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Zymomonas mobilis is an ethanol-producing alphaproteobacterium currently considered a major candidate organism for bioethanol production. Here we report the finished and annotated genome sequence of Z. mobilis subsp. mobilis strain NCIMB 11163, a British ale-infecting isolate. This is the first Z. mobilis strain whose genome, chromosomal and plasmid, is presented in its entirety.Zymomonas mobilis is a bacterium vigorously studied as a platform organism for bioethanol production in North America and other parts of the world. Z. mobilis converts sugars such as glucose or sucrose into ethanol and carbon dioxide to almost theoretical yields and to rates higher than those of yeasts (17). Genetically engineered strains that ferment pentoses in addition to naturally utilized hexoses also hold great promise for use in lignocellulosic biomass degradations (5, 22). Besides ethanol, Z. mobilis can produce other high-value chemicals such as sorbitol, levan, or phenylacetylcarbinol and has attracted interest for its unusual membrane steroid content (11). Lastly, Zymomonas is regarded as a safe organism and is even used for medicinal purposes (12, 20), which further facilitates its employment in large-scale biotechnological endeavors.The chromosomal sequence of the Z. mobilis subsp. mobilis industrial strain ATCC 31821 (ZM4) was recently published (19). Here we announce the first entire genome sequence of a Z. mobilis subsp. mobilis strain, that of the United Kingdom-originating strain NCIMB 11163 (B70) (20). Total DNA from NCIMB 11163 (16) was used for whole-genome shotgun sequencing at the U.S. DOE Joint Genome Institute. For this, an 8.7-kb DNA library and 454 and Solexa reads were used (http://www.jgi.doe.gov). Draft assemblies were based on 8,551 Sanger reads and 454 pyrosequencing to 20× coverage, whereas the Phred/Phrap/Consed software package was used for sequence assembly and quality assessment (6, 7, 9; http://www.phrap.com). After the shotgun stage, reads were assembled with parallel Phrap (High Performance Software, LLC), and misassemblies were corrected with Dupfinisher (10) or transposon bombing of bridging clones (Epicentre Biotechnologies, Madison, WI). A total of 144 primer walk reactions, five transposon bomb libraries, 53 PCR end reads, and two PCR shatter libraries were necessary to close gaps, resolve repetitive regions, and raise the quality of the finished sequence. The completed genome sequence of NCIMB 11163 was based on 11,048 reads, with an error rate of less than 6 bp out of 100,000 bp.Open reading frame prediction and annotation were performed using Prodigal (http://compbio.ornl.gov/prodigal/) and BLAST (1); tRNAscan-SE and RNAmmer (14, 15) were used for tRNA and rRNA recognition, respectively. Functional assignment of genes was performed by searching translated open reading frames against sequences in the SPTR (TrEMBL) (2), Pfam (8), TIGRFAMs (18), COG (21), and KEGG (13) databases.Z. mobilis NCIMB 11163 contains a single, circular chromosome of 2,124,771 bp and three plasmids, p11163_1, p11163_2, and p11163_3 of 53,380 bp, 40,818 bp, and 4,551 bp, respectively. The overall GC content of the chromosome is 46.83%, whereas those of the plasmids are 42.32%, 43.80%, and 36.37%, respectively. The entire genome of NCIMB 11163 contains 1,884 protein-encoding genes and 51 tRNA and nine rRNA genes, which are chromosomally located.The chromosome of NCIMB 11163 is 68,355 bp larger than that of ZM4 (GenBank accession number NC_006526) (19) and colinear at its largest part with that of ZM4 (genome structure comparisons were performed using ACT) (3). It bears several unique regions, among which are two genomic islands of ca. 25 and 79 kb, with no detectable nucleotide homology to same-species sequences and high regional similarity to chromosomal stretches of Paracoccus denitrificans PD1222 (GenBank accession number CP000489.1), Xanthobacter autotrophicus Py2 (GenBank accession number CP000781.1), and Gluconacetobacter diazotrophicus PAl 5 (GenBank accession number CP001189.1). Genome plasticity in NCIMB 11163 is further indicated by the presence of a type IV secretion system on the 79-kb island, syntenous to the Agrobacterium tumefaciens Ti (IncRh1) conjugal trb system (4), and also by multiple transposase and phage-related genes.In plasmids, housekeeping genes implicated in replication, active partitioning, and plasmid addiction are recognized, as well as genes involved in metabolism, transport, regulation, transposition, and DNA modification. Most notably, p11163_1 bears an arsenical resistance operon inserted in a type II secretion locus, whereas p11163_2, otherwise homologous to the 41-kb ZM4 plasmid (GenBank accession number AY057845), harbors a unique ca. 12-kb CRISPR insertion that interrupts nucleotide colinearity with the aforementioned replicon.  相似文献   
89.
In order to characterize the bacterial community diversity associated to mucus of the coral Mussismilia hispida, four 16S rDNA libraries were constructed and 400 clones from each library were analyzed from two healthy colonies, one diseased colony and the surrounding water. Nine bacterial phyla were identified in healthy M. hispida, with a dominance of Proteobacteria, Actinobacteria, Acidobacteria, Lentisphaerae, and Nitrospira. The most commonly found species were related to the genera Azospirillum, Hirschia, Fabibacter, Blastochloris, Stella, Vibrio, Flavobacterium, Ochrobactrum, Terasakiella, Alkalibacter, Staphylococcus, Azospirillum, Propionibacterium, Arcobacter, and Paenibacillus. In contrast, diseased M. hispida had a predominance of one single species of Bacteroidetes, corresponding to more than 70% of the sequences. Rarefaction curves using evolutionary distance of 1% showed a greater decrease in bacterial diversity in the diseased M. hispida, with a reduction of almost 85% in OTUs in comparison to healthy colonies. ∫-Libshuff analyses show that significant p values obtained were <0.0001, demonstrating that the four libraries are significantly different. Furthermore, the sympatric corals M. hispida and Mussismilia braziliensis appear to have different bacterial community compositions according to Principal Component Analysis and Lineage-specific Analysis. Moreover, lineages that contribute to those differences were identified as α-Proteobacteria, Bacteroidetes, and Firmicutes. The results obtained in this study suggest host–microbe co-evolution in Mussismilia, and it was the first study on the diversity of the microbiota of the endemic and endangered of extinction Brazilian coral M. hispida from Abrolhos bank.  相似文献   
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