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1.
Summary Twenty four castrated male, 6 intact male, and 11 intact female Hyla cinerea were injected subcutaneously with 25 g arginine-vasotocin (AVT) and induced to call 1 h later in response to the playback of a conspecific mating call. Eighteen castrated males and 8 intact females were implanted 5 mg androgen pellets for 3 weeks prior to the neuropeptide injection. Among castrated males, 6/9 testosterone (T) implanted, 4/9 dihydrotestosterone (DHT) implanted and 2/6 non implanted individuals produced calls after being administered AVT. 5/6 intact non implanted males and 6/8 T intact implanted females also called, and 3 intact non implanted females remained silent after the injection. Evoked calls had a mid-frequency spectral peak at about 1900 Hz which is absent in field-recorded mating calls of this species. Calls of implanted females and castrated non implanted males were shorter than those of castrated implanted and intact non implanted males. Audiograms measured before hormone implants showed dips of enhanced sensitivity at about 0.5, 0.9 and 3.0 kHz in males and females. After AVT injection, thresholds at frequencies within the 0.7–1.5 kHz range were increased in castrated males. Such reduction in sensitivity points to an inhibition of the auditory system during hormone induced vocal activation.Abbreviations AVT arginine-vasotocin - DHT dihydrotestosterone - T testosterone - TS torus semicircularis  相似文献   
2.
Summary The distribution of parvalbumin (PV) within neurons of the vocal motor nucleus hyperstriatum ventralepars caudalis (HVc) was investigated in the forebrain of adult male zebra finches by means of light and electron microscopy using the indirect immunoperoxidase technique. Parvalbumin-reaction product was located in the amorphous material of perikarya, dendrites and nuclei, and associated to microtubuli, postsynaptic densities and intracellular membranes; it was found in some axons and Gray type-2 boutons, but rarely in type-1 boutons and never in the Golgi apparatus. These observations suggest that parvalbumin may regulate calcium-dependent processes at the postsynaptic membrane and in the cytosol. Furthermore, the partial association of parvalbumin to microtubuli points to an involvement in calcium-dependent tubular functions. Calcium currents and microtubular assembly or transport may be relevant for the known functions of HVc in song learning.  相似文献   
3.
On the basis of protein modification studies and primary structure comparison, we propose that the SKS sequence within the KMSKS signature of the class 1 aminoacyl-tRNA synthetases corresponds to the GKT(or S) sequence considered as a signature of the nucleotide triphosphate-binding site of many proteins.  相似文献   
4.
The link between stapedius muscle activity and acoustic structure of vocalization was analysed in cocks of age 20–30 to 90–100 days old. The results show that stapedius muscle activation depends on the acoustic structure of vocalization and changes during vocal development. This dependence was observed in spontaneous calls and in vocalizations elicited by stimulating the mesencephalic calling area. In 30-day-old cocks stapedius muscle EMG response is never associated with vocalizations with an acoustic energy content which is always distributed at frequencies higher than 2000 Hz. The coupling between vocalization and stapedius muscle activity begins later, when birds produce vocalizations with acoustic energy shifted towards lower frequencies. Overall, stapedius muscle activity is related to a bird's production of high amplitude low frequencies. These results support the hypothesis that the primary role of the stapedius muscle during normal vocal development is to dampen the amplitude of low frequency energy that reaches the cochlea during vocalization.  相似文献   
5.
野外川金丝猴声音行为的主要类型   总被引:3,自引:0,他引:3  
李保国  罗时有 《兽类学报》1993,13(3):181-187
川金丝猴(Rhinopithecus roxellana)栖息于高山森林中,营树栖生活,其声音通讯在社群活动中有重要意义。通过长期野外行为的观察和声音的录制,本文报道了川金丝猴在野外自然活动条件下声音行为的主要类型,明显可以辩别出惊异声、警戒声、警告声、呼唤声和安静状态下的叫声,并进行了声谱分析,发现其声谱的差异主要与声音目的有关,同时描述了每类声音发出相伴随的群的行为和身体运动的变化,讨论了笼养条件下和野外状况下川金丝猴声音行为的异同。  相似文献   
6.
Tibetan goats, Taihang goats, Jining grey goats, and Meigu goats are the representative indigenous goats in China, found in Qinghai-Tibet Plateau, Western pastoral area, Northern and Southern agricultural regions. Very few studies have conducted a comprehensive analysis of the genomic diversity and selection of these breeds. We genotyped 96 unrelated individuals, using goat 53 K Illumina BeadChip array, of the following goat breeds: Tibetan (TG), Taihang (THG), Jining grey (JGG), and Meigu (MGG). A total of 45 951 single nucleotide polymorphisms were filtered to estimate the genetic diversity and selection signatures. All breeds had a high proportion (over 95%) of polymorphic loci. The observed and excepted heterozygosity ranged from 0.338 (MGG) to 0.402 (JGG) and 0.339 (MGG) to 0.395 (JGG), respectively. Clustering analysis displayed a genetically distinct lineage for each breed, and their Fst were greater than 0.25, indicating that they had a higher genetic differentiation between groups. Furthermore, effective population size reduced in all four populations, indicating a loss of genetic diversity. In addition, runs of homozygosity were mainly distributed in 5–10 Mb. Lastly, we identified signature genes, which were closely related to high-altitude adaptation (ADIRF) and prolificity (CNTROB, SMC3, and PTEN). This study provides a valuable resource for future studies on genome-wide perspectives on the diversity and selection signatures of Chinese indigenous goats.  相似文献   
7.
Characterization of WiDr: A human colon carcinoma cell line   总被引:1,自引:0,他引:1  
Summary We describe the establishment and characterization of WiDr, a cell line derived from a human colon carcinoma. It produces carcinoembryonic antigen in culture, and has a doubling time of 15 hr with plating efficiency of 51%. The HLA antigenic profile and the allozyme genetic signature (composed of eight gene-enzyme systems) of WiDr cells are different from those of HeLa cells. Furthermore, WiDr cells possess three marker chromosomes, again distinct from the HeLa marker chromosomes. Finally, it is highly tumorigenic in four different xenogeneic animal models. Based on these studies, WiDr represents a useful model cell line for tumor cell biology investigations.  相似文献   
8.
General theories (GT) are reductionist explications of apparently independent facts. Here, in reviewing the literature, I develop a GT to simplify the cluttered landscape of cancer therapy targets by revealing they cluster parsimoniously according to only a few underlying principles. The first principle is that targets can be only exploited by either or both of two fundamentally different approaches: causality‐inhibition, and ‘acausal’ recognition of some marker or signature. Nonetheless, each approach must achieve both of two separate goals, efficacy (reduction in cancer burden) and selectivity (sparing of normal cells); if the mechanisms are known, this provides a definition of rational treatment. The second principle is target fragmentation, whereby the target may perform up to three categoric functions (cytoreduction, modulation, cytoprotection), potentially mediated by physically different target molecules, even on different cell types, or circulating freely. This GT remains incomplete until the minimal requirements for cure, or alternatively, proof that cure is impossible, become predictable.  相似文献   
9.
Colorectal cancer (CRC) is one of the most commonly diagnosed cancers with an estimated 1.8 million new cases worldwide and associated with high mortality rates of 881 000 CRC‐related deaths in 2018. Screening programs and new therapies have only marginally improved the survival of CRC patients. Immune‐related genes (IRGs) have attracted attention in recent years as therapeutic targets. The aim of this study was to identify an immune‐related prognostic signature for CRC. To this end, we combined gene expression and clinical data from the CRC data sets of The Cancer Genome Atlas (TCGA) into an integrated immune landscape profile. We identified a total of 476 IRGs that were differentially expressed in CRC vs normal tissues, of which 18 were survival related according to univariate Cox analysis. Stepwise multivariate Cox proportional hazards analysis established an immune‐related prognostic signature consisting of SLC10A2, FGF2, CCL28, NDRG1, ESM1, UCN, UTS2 and TRDC. The predictive ability of this signature for 3‐ and 5‐year overall survival was determined using receiver operating characteristics (ROC), and the respective areas under the curve (AUC) were 79.2% and 76.6%. The signature showed moderate predictive accuracy in the validation and GSE38832 data sets as well. Furthermore, the 8‐IRG signature correlated significantly with tumour stage, invasion, lymph node metastasis and distant metastasis by univariate Cox analysis, and was established an independent prognostic factor by multivariate Cox regression analysis for CRC. Gene set enrichment analysis (GSEA) revealed a relationship between the IRG prognostic signature and various biological pathways. Focal adhesions and ECM‐receptor interactions were positively correlated with the risk scores, while cytosolic DNA sensing and metabolism‐related pathways were negatively correlated. Finally, the bioinformatics results were validated by real‐time RT?qPCR. In conclusion, we identified and validated a novel, immune‐related prognostic signature for patients with CRC, and this signature reflects the dysregulated tumour immune microenvironment and has a potential for better CRC patient management.  相似文献   
10.
Ovarian cancer (OvCa) causes the highest mortality among all gynaecologic cancers. A large number of mRNA‐ or miRNA‐based signatures were identified for OvCa patient prognosis. However, the comprehensive analysis of function‐level prognostic signatures is currently not considered in OvCa. In the present study, we respectively inferred subpathway activities from mRNA and miRNA levels based on high‐throughput expression profiles and reconstructed subpathways. Firstly, the activities of two tumour pathways were calculated and the difference between normal and tumour samples were analysed using multiple tumour types. Then, we calculated subpathway activities for OvCa based on the expression profiles from both mRNA and miRNA levels. Furthermore, based on these subpathway activity matrices, we performed bootstrap analysis to obtain sub‐training sets and utilized univariate method to identify robust OvCa prognostic subpathways. A comprehensive comparison of subpathway results between these two levels was performed. As a result, we observed subpathway mutual exclusion trend between the levels of mRNA and miRNA, which indicated the necessary of combining mRNA‐miRNA levels. Finally, by using ICGC data as testing sets, we utilized two strategies to verify survival predictive power of the mRNA‐miRNA combined subpathway signatures and performed comparisons with results from individual levels. It was confirmed that our framework displayed application to identify robust and efficient prognostic signatures for OvCa, and the combined signatures indeed exhibited advantages over individual ones. In the study, we took a step forward in relevant novel integrated functional signatures for OvCa prognosis.  相似文献   
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