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601.
Applied zeatin affected flowering in cuttings of Anagallis arvensis(long-day plant). According to the zeatin concentration andthe root formation stage, zeatin inhibited flowering at differentdegrees or slightly promoted it. Thus, the root primordium settingseemed to be correlated with this effect of zeatin. (Received February 14, 1984; Accepted May 18, 1984) 相似文献
602.
Eight cases of xeroderma pigmentosum are described-six in family B. and two in family T. The criteria used in making this diagnosis are indicated. The occurrence of epitheliomas and melanoma was observed. In family B. five of the six patients are alive at time of reporting, their ages varying from 40 to 55 years. In family T. the two affected children died at ages 8 and 14 years. The differential diagnosis between xeroderma pigmentosum and other conditions is briefly discussed. 相似文献
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Caroline Eymerit-Morin Anna Ilenko Thomas Gaillard Justine Varinot Eva Comprat Sofiane Bendifallah Emile Darai 《European journal of histochemistry : EJH》2021,65(1)
Therapeutic strategies for epithelial ovarian cancers are evolving with the advent of immunotherapy, such as PD-L1 inhibitors, with encouraging results. However, little data are available on PDL-1 expression in ovarian cancers. Thus, we set out to determine the PD-L1 expression according to histological subtype. We evaluated the expression of two PD-L1 clones – QR1 and E1L3N – with two scores, one based on the percentage of labeled tumor cells (tumor proportion score, TPS) and the other on labeled immune cells (combined proportion score, CPS) in a consecutive retrospective series of 232 ovarian cancers. PD-L1 expression was more frequent in high grade serous carcinoma (27.5% with E1L3N clone and 41.5% with QR1 clone), grade 3 endometrioid carcinoma (25% with E1L3N clone and 50% with QR1 clone), and clear-cell carcinomas (27.3% with E1L3N clone and 29.6% with QR1 clone) than other histological subtypes with CPS score. Using the CPS score, 17% of cases were labeled with E1L3N vs 28% with QR1. Using the TPS score, 14% of cases were positive to E1L3N vs 17% for QR1. For TPS and CPS, respectively, 77% and 78% of the QR1 cases were concordant with E1L3N for the thresholds of 1%. Overall and progression-free survival between PD-L1 positive and PD-L1 negative patients were not different across all histological types, and each subtype in particular for serous carcinomas expressing PD-L1. Expression of PD-L1 is relatively uncommon in epithelium ovarian tumors. When positive, usually <10% of tumor cells are labeled. QR1 clone and CPS appear the best tools to evaluate PD-L1 expression.Key words: Ovarian cancer, PD-L1 antibody, immunochemistry, histological subtype 相似文献
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Jean-Philippe Draye Guy Cheron Gaëtan Libert Emile Godaux 《Biological cybernetics》1997,76(5):365-374
The neural integrator of the oculomotor system is a privileged field for artificial neural network simulation. In this paper,
we were interested in an improvement of the biologically plausible features of the Arnold-Robinson network. This improvement
was done by fixing the sign of the connection weights in the network (in order to respect the biological Dale's Law). We also
introduced a notion of distance in the network in the form of transmission delays between its units. These modifications necessitated
the introduction of a general supervisor in order to train the network to act as a leaky integrator. When examining the lateral
connection weights of the hidden layer, the distribution of the weights values was found to exhibit a conspicuous structure:
the high-value weights were grouped in what we call clusters. Other zones are quite flat and characterized by low-value weights. Clusters are defined as particular groups of adjoining
neurons which have strong and privileged connections with another neighborhood of neurons. The clusters of the trained network
are reminiscent of the small clusters or patches that have been found experimentally in the nucleus prepositus hypoglossi,
where the neural integrator is located. A study was conducted to determine the conditions of emergence of these clusters in
our network: they include the fixation of the weight sign, the introduction of a distance, and a convergence of the information
from the hidden layer to the motoneurons. We conclude that this spontaneous emergence of clusters in artificial neural networks,
performing a temporal integration, is due to computational constraints, with a restricted space of solutions. Thus, information
processing could induce the emergence of iterated patterns in biological neural networks.
Received: 18 September 1996 / Accepted in revised form: 7 January 1997 相似文献
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Matthew E. Brown Elizabeth Rondon Deepika Rajesh Amanda Mack Rachel Lewis Xuezhu Feng Laura Jo Zitur Randall D. Learish Emile F. Nuwaysir 《PloS one》2010,5(6)
Induced pluripotent stem cells (iPSCs) hold enormous potential for the development of personalized in vitro disease models, genomic health analyses, and autologous cell therapy. Here we describe the generation of T lymphocyte-derived iPSCs from small, clinically advantageous volumes of non-mobilized peripheral blood. These T-cell derived iPSCs (“TiPS”) retain a normal karyotype and genetic identity to the donor. They share common characteristics with human embryonic stem cells (hESCs) with respect to morphology, pluripotency-associated marker expression and capacity to generate neurons, cardiomyocytes, and hematopoietic progenitor cells. Additionally, they retain their characteristic T-cell receptor (TCR) gene rearrangements, a property which could be exploited for iPSC clone tracking and T-cell development studies. Reprogramming T-cells procured in a minimally invasive manner can be used to characterize and expand donor specific iPSCs, and control their differentiation into specific lineages. 相似文献