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801.
《Endocrine practice》2023,29(6):428-435
ObjectiveTo develop and validate a risk stratification system for the prediction of malignancy in partially cystic thyroid nodules (PCTNs).MethodsWe retrospectively reviewed the sonography data of patients with PCTNs from 2 medical centers—Hangzhou Traditional Chinese Medicine Hospital and Hangzhou First People’s Hospital—from January 2020 to December 2021. The independent risk factors for malignant PCTNs were evaluated using the univariate and multivariate logistic regression analyses. The nomogram prediction efficiency was assessed using the area under the curve and calibration curves. The decision curve analysis was used to determine the clinical value of the predictive model.ResultsA total of 285 patients were enrolled in this retrospective study, and of 301 PCTNs, 242 were benign and 59 were malignant. Younger age, hypoechoic, irregular margin, and microcalcifications were found to be the independent risk factors for malignant PCTNs. The area under the curve, sensitivity, and specificity were 0.860, 77.1%, and 84.7% in the training data set and 0.897, 91.7%, and 87.0% in the external validation data set, respectively. The total point of nomogram was >161, which showed the best to predict malignancy in PCTNs.ConclusionOur findings demonstrated that the risk stratification system for the assessment of PCTNs showed good prediction capacities. 相似文献
802.
《IRBM》2022,43(3):187-197
Objectives: Middle ear inflammatory diseases are global health problem that can have serious consequences such as hearing loss and speech disorders. The high cost of medical devices such as oto-endoscope and oto-microscope used by the specialists for the diagnosis of the disease prevents its widespread use. In addition, the decisions of otolaryngologists may differ due to the subjective visual examinations. For this reason, computer-aided middle ear disease diagnosis systems are needed to eliminate subjective diagnosis and high cost problems. To this aim, a hybrid deep learning approach was proposed for automatic recognition of different tympanic membrane conditions such as earwax plug, myringosclerosis, chronic otitis media and normal from the otoscopy images.Materials and methods: In this study we used public Ear Imagery dataset containing 880 otoscopy images. The proposed approach detects keypoints from the otoscopy images and following the obtained keypoint positions, extracts hypercolumn deep features from 5 different layers of the VGG 16 model. Classification of tympanic membrane conditions were realized by feeding the deep hypercolumn features to Bi-LSTM network in the form of non-time related data.Results: The performance of the proposed model was evaluated in three different color spaces as Red-Green-Blue (RGB), Hue-Saturation-Value (HSV) and Haematoxylin-Eosin-Diaminobenzidine (HED). The proposed model achieved acceptable results in all color spaces, moreover it showed a very successful performance in classifying tympanic membrane conditions especially in RGB space. Experimental studies showed that the proposed model achieved Acc of 99.06%, Sen of 98.13% and Spe of 99.38%.Conclusion: As a result, a robust model with high sensitivity was obtained for classification of tympanic membrane conditions and it was shown that Bi-LSTM network, which is generally used with time-related data, could also be used successfully with non-time related data for diagnosis of tympanic membrane conditions. 相似文献
803.
Breeding biology in Phyllomedusa sauvagii is related to vegetation since the species encloses its eggs in leaves above water. Considering that arid environments may represent high risks of death by desiccation for amphibians with this reproductive mode, we evaluated plant characteristics associated with sites used for oviposition in semi-permanent ponds in the Arid Chaco region of Argentina. Plant characteristics were used to fit a statistical habitat selection model that allows the prediction of nest presence. Our results show that P. sauvagii needs substrate with specific features for oviposition that would help to reduce the probability of eggs and tadpoles desiccation. 相似文献
804.
This study compares the initial orientation and homing performance of young inexperienced pigeons following their transportation
to near and distant places in total darkness (treatment) and their subsequent release. The birds were housed in two lofts
at the Lisbon Zoo. Each loft had its own specific features: the H-loft was exposed to prevailing winds and allowed an unhindered
view of the surrounding landscape; the L-loft was protected from the wind and allowed only a partial view of the surroundings.
Pigeons used in the release tests were between 6 and 7 weeks old. We found that, in general, the initial orientation of the
pigeons was affected by the treatment: following release at near places, there was an increase in the scatter and a decrease
the homeward component, suggesting that light-dependent information collected en route was used by young pigeons. The effect
of the treatment was only temporary based on the observation that the homing performance was not affected. However, the distance
of the release site strongly influenced the homing performances as pigeons appeared to be unable to home when released at
locations distant from the loft. Based on the scatter or the homeward component, inter-loft differences were apparent with
respect to different median vanishing intervals and the reactions of specific pigeons when subjected to the same treatment
(transport in darkness) following release at near and distant places. These findings suggest that light-dependent information
collected en route is a component of the young pigeon’s navigational system but that, at the young age of the birds tested
here, it is preferentially used in familiar areas. In addition, the importance of the light-dependent information appears
to depend upon prior experience obtained in the lofts. 相似文献
805.
KARI BJØRNERAAS BRAM VAN MOORTER CHRISTER MOE ROLANDSEN IVAR HERFINDAL 《The Journal of wildlife management》2010,74(6):1361-1366
Abstract: Animal locations estimated by Global Positioning System (GPS) inherently contain errors. Screening procedures used to remove large positional errors often trade data accuracy for data loss. We developed a simple screening method that identifies locations arising from unrealistic movement patterns. When applied to a large data set of moose (Alces alces) locations, our method identified virtually all known errors with minimal loss of data. Thus, our method for screening GPS data improves the quality of data sets and increases the value of such data for research and management. 相似文献
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Kyoungwon ChoYounsoo Han Je Chang WooBianca Baudisch Ralf Bernd KlösgenSeunghan Oh Jihoon HanOksoo Han 《Plant science》2011,181(3):242-248
The dual positional maize lipoxygenase-1 was introduced into rice and T2 transgenic plants were produced. Cellular location of maize lipoxygenase-1 in transgenic rice and effects of calcium ion on membrane association in vitro were analyzed. Localization study by confocal microscopic analysis indicated that the maize lipoxygenase-1 was localized in cytoplasm. Sucrose-density fractionation experiment and in vitro protein transport to chloroplast showed that the maize lipoxygenase-1 can be associated with chloroplast. Secondary structure alignment revealed putative calcium binding sites in the PLAT domain of maize lipoxygenase-1 and the association of the maize lipoxygenase-1 with membranes was mediated by calcium ion in vitro. Our results provide evidences for calcium-mediated translocation of dual positional LOX without chloroplast targeting sequence from cytoplasm to chloroplast in plants for the first time. 相似文献
810.
Marluce Bibbo Peter H. Bartels Harvey E. Dytch James H. Puls Frederick T. Pishotta George L. Wied 《Cell biochemistry and biophysics》1983,5(1):61-69
Comparison was made between cytophotometric measurements obtained using two data acquisition systems, one a microphotometer
and the other a rapid video camera system, to ascertain whether the degradation of data with the faster video acquisition
system still results in recorded images of sufficient quality to permit computer discrimination between cells of very similar
appearance. Normal-appearing intermediate cells from cases with normal cytology and those from patients with dysplasia or
malignant disease, as well as the subvisual markers within these cells that have rendered them capable of cytophotometric
discrimination, were used for the study. Comparison of the data recorded by the two systems indicates that the diagnostic
information is preserved in the change-over to a full-field, video-rate scanning system, with differences in the data caused
primarily by differences in the spectral response of the two systems. This was reflected in the substantial differences observed
in the color-related features and the lesser differences seen in the textural features, while the morphometric features (outline
and shape) were virtually unaffected. The differences were primarily expressed on a cell-to-cell basis; in sets of about 300
cells, which would be used in patient-to-patient comparisons, the feature values showed remarkable consistency between the
two systems. 相似文献