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71.
Bellintani-Guardia B Ott M 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,145(1):56-63
Retinal ganglion cells were successfully labelled in the chameleon by retrograde axonal transport of dextran amines that were applied to the nucleus of the basal optic root (nBOR) in an in vitro preparation. Labelled ganglion cells were restricted to the contralateral eye. Many cells were completely stained including their dendritic trees. With few exceptions, all cells had displaced somata that were located at the inner margin of the inner nuclear layer. The labelled ganglion cells had two to six primary dendrites that branched frequently and formed large unistratified dendritic trees within sublamina 1 of the inner plexiform layer. There was extensive overlap of the dendritic trees of neighbouring cells leading to an estimated coverage factor of 2-4. The dendritic field areas varied in size according to the retinal position of the cells and were highest in the central retina around the fovea with a maximum of 0.14 mm(2) and reached a second maximum at the retinal margin with values of 0.08-0.1 mm(2). The smallest dendritic areas (0.04-0.06 mm(2)) were measured midway between the fovea and retinal margin. The size of the soma area was not correlated to the dendritic field size and increased from 100 to 150 microm(2) near the fovea to 150-300 microm(2) at the retinal margin. There was no evidence for a retinotopic organisation of ganglion cell fibres within the nBOR. All cells were of uniform morphology that was identical to the type of nBOR-projecting displaced ganglion cell (DGC) described previously for the bird retina. Similar to birds, the labelled DGCs were the only source of retinal projection to the nBOR. A small fraction of cells had orthotopic somata located in the ganglion cell layer but were otherwise identical to the labelled DGCs. The similarity of chameleon nBOR-projecting ganglion cells to those described in avian retinas mirrors the close phylogenetic relationship of birds and lizards. 相似文献
72.
目的: 探讨在高转移人乳腺癌细胞中,核因子κB活性对肿瘤生长及运动迁移能力的影响。方法: 转染显性负性突变的ⅠκBα重组质粒入高转移乳腺癌细胞MDA-MB-231、MDA-MB-435,筛选并鉴定稳定转染的细胞株;凝胶迁移实验观察核因子κB活性,细胞生长曲线、平板集落形成试验及Millicell-PCF培养小室观察质粒转染对细胞生长和趋化运动的影响。结果: 乳腺癌MDA-MB-231、MDA-MB-435细胞中存在高NF-κB组成型激活,稳定转染显性负性的ⅠκBα质粒后,细胞NF-κB活性下调,在不明显影响细胞生长、克隆形成的情况下,抑制高转移乳腺癌细胞株的运动能力。结论: 在体外,抑制NF-κB通路,可明显抑制高转移乳腺癌细胞株的运动迁移能力。 相似文献
73.
Bexander CS Mellor R Hodges PW 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,167(3):422-432
Control of the neck muscles is coordinated with the sensory organs of vision, hearing and balance. For instance, activity
of splenius capitis (SC) is modified with gaze shift. This interaction between eye movement and neck muscle activity is likely
to influence the control of neck movement. The aim of this study was to investigate the effect of eye position on neck muscle
activity during cervical rotation. In eleven subjects we recorded electromyographic activity (EMG) of muscles that rotate
the neck to the right [right obliquus capitis inferior (OI), multifides (MF), and SC, and left sternocleidomastoid (SCM)]
with intramuscular or surface electrodes. In sitting, subjects rotated the neck in each direction to specific points in range
that were held statically with gaze either fixed to a guide (at three different positions) that moved with the head to maintain
a constant intra-orbit eye position or to a panel in front of the subject. Although right SC and left SCM EMG increased with
rotation to the right, contrary to anatomical texts, OI EMG increased with both directions and MF EMG did not change from
the activity recorded at rest. During neck rotation SCM and MF EMG was less when the eyes were maintained with a constant
intra-orbit position that was opposite to the direction of rotation compared to trials in which the eyes were maintained in
the same direction as the head movement. The inter-relationship between eye position and neck muscle activity may affect the
control of neck posture and movement. 相似文献
74.
Carlo Cervia Jakob Nilsson Yves Zurbuchen Alan Valaperti Jens Schreiner Aline Wolfensberger Miro E. Raeber Sarah Adamo Sebastian Weigang Marc Emmenegger Sara Hasler Philipp P. Bosshard Elena De Cecco Esther Bächli Alain Rudiger Melina Stüssi-Helbling Lars C. Huber Annelies S. Zinkernagel Onur Boyman 《The Journal of allergy and clinical immunology》2021,147(2):545-557.e9
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75.
A wireless recording system was developed to study the electroencephalogram (EEG) in unrestrained, male Landrace piglets. Under general anesthesia, ball-tipped silver/silver chloride electrodes for EEG recording were implanted onto the dura matter of the parietal and frontal cortex of the piglets. A pair of miniature preamplifiers and transmitters was then mounted on the surface of the skull. To examine whether other bioelectrical activities interfere with the EEG measurements, an electrocardiogram (ECG) or electromyogram (EMG) of the neck was simultaneously recorded with the EEG. Next, wire electrodes for recording movement of the eyelid were implanted with EEG electrodes, and EEG and eyelid movements were simultaneously measured. Power spectral analysis using a Fast Fourier Transformation (FFT) algorithm indicates that EEG was successfully recorded in unrestrained piglets, at rest, during the daytime in the absence of interference from ECG, EMG or eyelid movements. These data indicate the feasibility of using our radiotelemetry system for measurement of EEG under these conditions. 相似文献
76.
The third derivative of motion or the change in the rate of acceleration (also known as jerk) is examined in terms of its applicability to the study of psychophysiological function. An algorithm of this third derivative is presented to show that jerk can be derived from the arithmetic difference of two slopes which constitute the portion of motion being differentiated. By modifying the algorithm, a new parameter termed “proportional jerk’ or PJ is formulated whereby one slope is measured relative to the other slope; this PJ provides information about the smoothness of movement without being influenced by the velocity as is the traditional jerk measure. A practical application of the PJ to waking saccades and REMs in 11 human subjects revealed that REMs are significantly “jerkier’ or less smooth than waking calibration eye movements. Whereas the waking eye movements had a well-defined negative phase of the PJ, the REMs did not show such stereotypical behavior. This is in accord with previous work which showed that waking saccade velocity increases to a maximum and then decreases whereas REMs maintain their peak or near peak velocities for varying periods. It was suggested that PJ can be useful in detecting subtle temporal changes in the course of movements and may be used as a parameter of motion even when the absolute amplitude is unknown. 相似文献
77.
The effects of environmental constraints upon licking patterns 总被引:1,自引:0,他引:1
Rats licked water under three degrees of environmental constraint. As restriction decreased, lick duration increased. Interlick interval changed independently of duration. Lickometer-measured drinking tube contact was longer than fluid contact unless access was highly restricted. The use of controlled access to measure minimal necessary taste input is discussed. 相似文献
78.
Kun?Guo Robert?G.?RobertsonEmail author Sasan?Mahmoodi Yoav?Tadmor Malcolm?P.?Young 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,150(3):363-374
Face perception plays a crucial role in primate social communication. We have investigated the pattern of eye movements produced
by rhesus monkeys (Macaca mulatta) as they viewed images of faces. Eye positions were recorded accurately using implanted eye coils, while neutral upright,
inverted and scrambled images of monkey and human faces were presented on a computer screen. The monkeys exhibited a similar
eye scan pattern while viewing familiar and unfamiliar monkey face images, or while viewing monkey and human face images.
No differences were observed in the distribution of viewing times, number of fixations, time into the trial of first saccade
to local facial features, and the temporal and spatial characteristics of viewing patterns across the facial images. However,
there was a greater probability of re-fixation of the eye region of unfamiliar faces during the first few seconds of the trial
suggesting that the eyes are important for the initial encoding of identity. Indeed, the highest fixation density was found
in the eye region of all the face images. The viewing duration and the number of fixations per image decreased when inverted
or scrambled faces were presented. The eye region in these modified images remained the primary area of fixation. However,
the number of fixations directed to the eyes decreased monotonically from the upright images through the inverted versions
to the scrambled face images. Nonetheless, the eyes remain the most salient facial substructure regardless of the arrangement
of other features, although the extent of salience which they attain may depend both on the low level properties of the eyes
and on the global arrangement of facial features.
Electronic Publication 相似文献
79.
Nikolaos Smyrnis Masato Taira James Ashe Apostolos P. Georgopoulos 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,92(1):139-151
Summary Two rhesus monkeys were trained to move a handle on a two-dimensional (2D) working surface in directions specified by a light at the plane. They first captured with the handle a light on the center of the plane and then moved the handle in the direction indicated by a peripheral light (cue signal). The signal to move (go signal) was given by turning off the center light. The following tasks were used: (a) In the non-delay task the peripheral light was turned on at the same time as the center light went off. (b) In the memorized delay task the peripheral light stayed on for 300 ms and the center light was turned off 450–750 ms later. Finally, (c) in the non-memorized delay task the peripheral light stayed on continuously whereas the center light went off 750–1050 ms after the peripheral light came on. Recordings in the arm area of the motor cortex (N= 171 cells) showed changes in single cell activity in all tasks. In both delay tasks, the neuronal population vector calculated every 20 ms after the onset of the peripheral light pointed in the direction of the upcoming movement, which was instructed by the cue light. Moreover, the strength of the population signal showed an initial peak shortly after the cue onset in both the memorized and non-memorized delay tasks but it maintained a higher level during the memorized delay period, as compared to the non-memorized task. These results indicate that the motor cortex is involved in encoding and holding in memory directional information concerning a visually cued arm movement and that these processes can be visualized using neuronal population vector analysis. 相似文献
80.
James W. Verbsky Mary K. Hintermeyer Pippa M. Simpson Mingen Feng Jody Barbeau Nagarjun Rao Carlyne D. Cool Luis A. Sosa-Lozano Dhiraj Baruah Erin Hammelev Alyssa Busalacchi Amy Rymaszewski Jeff Woodliff Shaoying Chen Mary Bausch-Jurken John M. Routes 《The Journal of allergy and clinical immunology》2021,147(2):704-712.e17