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《Médecine Nucléaire》2020,44(4):231-249
The original thyroid scan (TS) was widely used to identify typical imaging patterns, suggesting the widely accepted main following clinical diagnoses: Grave's disease, Toxic adenoma, [hetero]-nodular goiters and thyroiditis. With the diffusion of sensitive TSH assays, considerable advances in the comprehension of the molecular mechanisms of hormonosynthesis, and new quantification possibilities especially using 123I, the TS is a textbook of molecular imaging. The image can be finely quantified with, not only as regards the Uptake (123IUp) and related parameters but also, the quantification of the spatial targeting leading to a Spatial Target Index (STI). Using this new molecular 123I-TS, TSH values, and when required, correlation to Multiparametric Ultrasounds (MPUS), we generated a basic classification system of hyperthyroidism, with well-defined indexed criteria (C11-1 to C17-3), that allows reporting 24 distinct etiologies. Selected criteria involve TS and contrast patterns, precocious 123IUp (p123IUp), maximal TSH-dependent physiological Uptake, lobar concentration, Uptake and concentration ratios, STI, 99mTc-MIBI TS and correlative MPUS. This approach allows to identify 4 subtypes of Graves’ disease, including hyperplastic, nodular and common GD variants entangled with Hashimoto's struma, 4 subtypes of Thyroid Functional Autonomy, including Disseminated Functional Autonomy, that cannot be diagnosed with other conventional procedures. Criteria C14-1 to C17-3 report on hyperthyroidism and iodine overload, factitia, main thyroiditis presentations and rare central or tumoral etiologies of hyperthyroidism. This classification, based on 123I-TS molecular imaging, leads to unprecedented diagnostic finesse and paves the way for a personalized theranostic approach in thyroid pathology. Further development towards artificial intelligence networks is under study. 相似文献
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Qundan Lv Jie Qiu Jie Liu Zheng Li Wenting Zhang Qin Wang Jie Fang Junjie Pan Zhengdao Chen Wenliang Cheng Michael S. Barker Xuehui Huang Xin Wei Kejun Cheng 《The Plant journal : for cell and molecular biology》2020,103(5):1910-1923
Chimonanthus salicifolius, a member of the Calycanthaceae of magnoliids, is one of the most famous medicinal plants in Eastern China. Here, we report a chromosome‐level genome assembly of C. salicifolius, comprising 820.1 Mb of genomic sequence with a contig N50 of 2.3 Mb and containing 36 651 annotated protein‐coding genes. Phylogenetic analyses revealed that magnoliids were sister to the eudicots. Two rounds of ancient whole‐genome duplication were inferred in the C. salicifolious genome. One is shared by Calycanthaceae after its divergence with Lauraceae, and the other is in the ancestry of Magnoliales and Laurales. Notably, long genes with > 20 kb in length were much more prevalent in the magnoliid genomes compared with other angiosperms, which could be caused by the length expansion of introns inserted by transposon elements. Homologous genes within the flavonoid pathway for C. salicifolius were identified, and correlation of the gene expression and the contents of flavonoid metabolites revealed potential critical genes involved in flavonoids biosynthesis. This study not only provides an additional whole‐genome sequence from the magnoliids, but also opens the door to functional genomic research and molecular breeding of C. salicifolius. 相似文献
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Gregg W C Thomas Richard J Wang Jelena Nguyen R Alan Harris Muthuswamy Raveendran Jeffrey Rogers Matthew W Hahn 《Molecular biology and evolution》2021,38(4):1460
Mutations play a key role in the development of disease in an individual and the evolution of traits within species. Recent work in humans and other primates has clarified the origins and patterns of single-nucleotide variants, showing that most arise in the father’s germline during spermatogenesis. It remains unknown whether larger mutations, such as deletions and duplications of hundreds or thousands of nucleotides, follow similar patterns. Such mutations lead to copy-number variation (CNV) within and between species, and can have profound effects by deleting or duplicating genes. Here, we analyze patterns of CNV mutations in 32 rhesus macaque individuals from 14 parent–offspring trios. We find the rate of CNV mutations per generation is low (less than one per genome) and we observe no correlation between parental age and the number of CNVs that are passed on to offspring. We also examine segregating CNVs within the rhesus macaque sample and compare them to a similar data set from humans, finding that both species have far more segregating deletions than duplications. We contrast this with long-term patterns of gene copy-number evolution between 17 mammals, where the proportion of deletions that become fixed along the macaque lineage is much smaller than the proportion of segregating deletions. These results suggest purifying selection acting on deletions, such that the majority of them are removed from the population over time. Rhesus macaques are an important biomedical model organism, so these results will aid in our understanding of this species and the disease models it supports. 相似文献
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A new discovery of Neanderthal settlements in Turkey: Sürmecik open-air campsite in Western Anatolia
《L'Anthropologie》2021,125(1):102838
Western Anatolia is the poorest region in terms of Turkey's Palaeolithic finds. In the past years, only a few Palaeolithic artefacts were known from the surface in the provinces of İzmir, Manisa, Kütahya and Afyonkarahisar in western Anatolia. After the fossil Homo erectus skull fragment was found in the travertine deposits in Kocabaş (Denizli) in 2002, the importance of the region more increased. After this important discovery, Dr. Kadriye Özçelik started a Palaeolithic survey in Denizli and found a large number of chipped stone tools from the Lower and Middle Palaeolithic periods. Nevertheless, the last important Palaeolithic discovery in the region was made in Sürmecik (Banaz-Uşak) in 2015. This is an open-air campsite belonging to the Middle Palaeolithic period. Here is also a mining area where a mining operation is conducted. The chipped stone artefacts of the Sürmecik Palaeolithic open-air campsite come from a clay layer between hematite and limonite deposits under a travertine layer of about 4.5–5 meters in thickness. Faunal remains represent mostly by equids species. All stages of Mousterian culture are clearly visible in this open-air campsite. Sürmecik is the richest middle Palaeolithic open-air campsite in Turkey. The 83,002 lithic pieces were collected in the excavations carried out in 2016 and 2017. It is thought that the lithic assemblage will exceed 100,000 with the ongoing studies. The group of bifacial leaf points in this collection is seen in Turkey for the first time. Four master thesis studies started on the lithic material of Sürmecik. It is planned to take some samples for dating analysis along with ongoing studies. 相似文献