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31.
C. Jiang J. Lipski 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1990,81(3):639-648
Summary Axonal projections and synaptic connectivity of expiratory B?tzinger neurons with an augmenting firing pattern (Bot-Aug neurons)
to neurons in the ipsilateral ventral respiratory group (VRG) were studied in anaesthetized cats. Antidromic mapping revealed
extensive axonal arborizations of Bot-Aug neurons (24 of 45) to the rostral or caudal VRG, with some having arbors in both
regions. Of 234 pairs of neurons studied with intracellular recording and spike-triggered averaging, monosynaptic inhibitory
postsynaptic potentials (IPSPs) were evoked in 49/221 VRG neurons by 38/98 Bot-Aug neurons. The highest incidence of monosynaptic
inhibition was found in inspiratory bulbospinal neurons (10 of 23 tested). Evidence was also found for monosynaptic inhibition,
by a separate group of Bot-Aug neurons, of expiratory bulbospinal neurons (12/58), while excitatory postsynaptic potentials
(EPSPs) were identified in another two of these neurons. In addition, monosynaptic IPSPs were recorded from 13 of 53 identified
laryngeal motoneurons, and from 14 of 100 respiratory propriobulbar neurons. Presumptive disynaptic IPSPs were recorded from
11 of the 221 VRG neurons. We conclude that Bot-Aug neurons exert widespread inhibition on all major neuron categories in
the ipsilateral VRG, and should be regarded as an important element in shaping the spatiotemporal output pattern of both respiratory
motoneurons and premotor neurons. 相似文献
32.
Teresa Sagalés Victor Gimeno M. Dolores de la Calzada Francesc Casellas M. Dolors Macià M. Villar Soriano 《Brain topography》1990,2(3):221-228
Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients. 相似文献
33.
Anete M. Francisco‐Bagnariolli Spencer L.M. Payão Rosa S. Kawasaki‐Oyama Daher Sabbag Filho Rosimeire Segato Roger W. de Labio Maria de Lourdes L.F. Chauffaille Jean H. Priest 《American journal of medical genetics. Part A》2001,103(4):302-307
We report on a familial t(4;7)(q28;p22) with 2:2 adjacent‐1 unbalanced segregation producing duplication of 4q28→qter in multiple offspring. Within the large four‐generation pedigree, a carrier had a reproductive outcome that was approximately equal for 1) the balanced translocation, 2) normal chromosomes, and 3) viable 4q trisomy or pregnancy loss. The three individuals with chromosomal confirmation of trisomy 4q28→qter (comprising approximately 1.8% of the haploid autosomal length) had similar mental and developmental retardation, hypotonia, restricted speech, seizures, and facial anomalies but no cardiac, renal, or skeletal anomalies. It is suggested that these latter severe malformations, associated with the classic 4q2 to 3 group of anomalies, were from an imbalance outside 4q28→qter and were not necessarily related to the relatively large size of the trisomic segment. Multiple different chromosomes are reported to be rearranged with 4q in the production of distal 4q trisomy. The incidence of 4q rearrangement remains unexplained, but once it is present in a family, viability of a large trisomy in 4q seems to explain the number of affected individuals reported. © 2001 Wiley‐Liss, Inc. 相似文献
34.
Uylings HB Rajkowska G Sanz-Arigita E Amunts K Zilles K 《Anatomy and embryology》2005,210(5-6):423-431
In human brain imaging studies, it is common practice to use the Talairach stereotaxic reference system for signifying the
convergence of brain function and structure. In nearly all neuroimaging reports, the studied cortical areas are specified
further with a Brodmann Area (BA) number. This specification is based upon macroscopic extrapolation from Brodmann’s projection
maps into the Talairach atlas rather than upon a real microscopic cytoarchitectonic study. In this review we argue that such
a specification of Brodmann area(s) via the Talairach atlas is not appropriate. Cytoarchitectonic studies reviewed in this
paper show large interindividual differences in 3-D location of primary sensory cortical areas (visual cortex) as well as
heteromodal associational areas (prefrontal cortical areas), even after correction for differences in brain size and shape.
Thus, the simple use of Brodmann cortical areas derived from the Talairach atlas can lead to erroneous results in the specification
of pertinent BA. This in turn can further lead to wrong hypotheses on brain system(s) involved in normal functions or in specific
brain disorders. In addition, we will briefly discuss the different ‘Brodmann’ nomenclatures which are in use for the cerebral
cortex. 相似文献
35.
Although it is generally accepted that human superior temporal gyrus is activated by a huge variety of auditory and linguistic
tasks, little is known about the exact positions and extents of cortical areas that are located on the lateral convexity of
the gyrus (e.g., Brodmann’s area 22). Such information, however, is relevant for a rigorous testing of structural-functional
relationships in both normal volunteers and patients suffering from disorders of auditory and language perception. The present
combined cytoarchitectonic and receptorarchitectonic study identifies a distinct area (Te3) in the lateral bulge of the superior
temporal gyrus by using an algorithm-based approach for the detection of cortical borders. Our mapping data show that, in
contrast to Brodmann’s area (BA) 22, only small portions of Te3 reach the dorsal and ventral banks of the gyrus. Therefore,
we labelled the newly defined area as “Te3” and not as “BA 22”. The cytoarchitectonically defined borders of Te3 coincide
with abrupt changes in the receptorarchitecture of several classical neurotransmitters, suggesting that Te3 represents a functionally
relevant area of the human superior temporal gyrus. Since position and extent of area Te3 varied considerably between subjects,
probability maps were created that show for each voxel of the standard references space, the frequency with which Te3 was
present in it. These maps, in combination with previously published maps of the primary auditory cortex, can directly be compared
with functional imaging data, and may open new perspectives for the analysis of structural-functional correlations in the
human auditory and language systems. 相似文献
36.
脑电(Electroencephalography, EEG)和功能磁共振(Functional magnetic resonance imaging, fMRI)技术的结合,可以实现两者优势的互补,获得更加合理的源定位结果.本文报道的是一种将fMRI先验信息结合到脑电源定位中的新方法.在该方法中,先利用SPM方法计算获得fMRI的统计映射参数,然后将基于计算获得的统计参数构造的权矩阵结合到FOCUSS的迭代过程中,对脑电的反演提供具有fMRI先验空间位置信息的约束,提高脑电的源空间定位精度,从而获得更加合理的定位结果.通过对一形状知觉实验fMRI和脑电数据的结合定位分析,结果初步证实了改进方法能获得和生理更加一致的结果. 相似文献
37.
Restriction fragment differences between the genomes of the Oka varicella vaccine virus and American wild-type varicella-zoster virus 总被引:5,自引:0,他引:5
The Oka vaccine strains of varicella-zoster virus (VZV) have a significantly different BgII DNA restriction pattern from that of American wild-type isolates of VZV. This difference consists primarily of an additional BgII site, which lies within the BamHI "D" fragment. In conjunction with a study of the efficacy of an experimental Merck/Oka VZV vaccine, the area of the genome from which the most marked restriction pattern alteration arises was studied more closely to determine if there are other significant differences between the Oka strains and American wild-type strains. BamHI "D" fragments from the DNA of the Oka parent strain (the progenitor of the vaccine strain), the RIT/Oka vaccine strain (a derivative of the Oka parent strain), the Merck/Oka vaccine strain, and the EF strain (an American wild type), were submitted to extensive endonuclease digestion studies to ascertain if additional unique restriction sites are present in the Oka parent or vaccine strains. The extra BgII restriction site characteristic of the Merck/Oka vaccine strain is also present in the DNA of the parent virus as well as its derivatives and was therefore not produced by the "attenuation" process. No other novel sites were found in the Oka parent or Oka-derived strains in this section of the genome. The Merck/Oka vaccine strain of VZV, despite its Japanese origin, is therefore quite similar to circulating American varicella-zoster virus strains. Varicella-zoster virus DNA, at least in the area of the BamHI D fragment, also appears to be remarkably stable from strain to strain. 相似文献
38.
Paul B. Samollow Nicolas Gouin Pat Miethke Susan M. Mahaney Margaret Kenney John L. VandeBerg Jennifer A. Marshall Graves Candace M. Kammerer 《Chromosome research》2007,15(3):269-282
The genome of the gray, short-tailed opossum, Monodelphis domestica, will be the first of any marsupial to be fully sequenced. The utility of this sequence will be greatly enhanced by construction
and integration of detailed genetic and physical maps. Therefore, it is important to verify the unusual recombinational characteristics
that were suggested by the ‘first-generation’ M. domestica linkage map; specifically, very low levels of recombination and severely reduced female recombination, both of which are
contrary to patterns in other vertebrates. We constructed a new linkage map based on a different genetic cross, using a new
and much larger set of map markers, and physically anchored and oriented the linkage groups onto chromosomes via fluorescence
in-situ hybridization mapping. This map includes 150 loci in eight autosomal linkage groups corresponding to the eight autosome pairs,
and spans 86–89% of the autosomal genome. The sex-averaged autosomal map covers 715 cM, with a full-length estimate of 866 cM;
the shortest full-length linkage map reported for any vertebrate. The sex-specific maps confirmed severely reduced female
recombination in all linkage groups, and an overall F/M map ratio = 0.54. These results greatly extend earlier findings,
and provide an improved microsatellite-based linkage map for this species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
39.
Keiko Wakui Toshiro Nishida Jun-ichiro Masuda Takeshi Itoh Daisuke Katsumata Tsutomu Ohno Yoshimitsu Fukushima 《Journal of human genetics》1991,36(2):149-153
We report a malformed female infant withde novo interstitial deletion of 4q[46,XX,del(4)(q27q28.2)]. The MN blood type analysis of the family members showed that the patient had an intact blood group-MN locus. The locus of the gene responsible for the MN antigen activity is confined to a 4q28.2–4q31.1 segment on the basis of the result of this patient and the previous mapping data. 相似文献
40.
This paper presents results of a study to establish a link between neurocognitive psychophysiological and psychological type data through the investigation of differences in topographic auditory event-related potential (AERP) (P300) patterns in strongly introverted (n = 17) and strongly extraverted ( = 16) high school males as identified by the Myers Briggs Type Indicator. Group data files were created for the auditory event related potential task and converted to ASCII form. Amplitude values were evaluated at each scalp site. Kruskal Wallis one way analysis of variance was performed to evaluate group differences. In processing of infrequent, target stimuli, the amplitude of the P300 waveform for introverts was higher than for extraverts. When processing for non-target stimuli was subtracted from target stimuli, statistical differences were found over nine central, parietal, and occipital sites. The findings support and extend theories of biologically-based and bio-psycho-social typology. 相似文献