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101.
Jürgen Dressnandt Uwe Jürgens 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,89(3):549-559
Summary In 11 squirrel monkeys (Saimiri sciureus), the brain stem was systematically explored with electrical brain stimulation for sites affecting the acoustic structure of ongoing vocalization. Vocalization was elicited by electrical stimulation of different brain structures. A severe deterioration of the acoustical structure of vocalization was obtained during stimulation of the caudoventral part of the periaqueductal grey, lateral parabrachial area, corticobulbar tract, nucl. ambiguus and surrounding reticular formation, facial nucleus, hypoglossal nucleus, solitary tract nucleus and along the fibres crossing the midline at the level of the hypoglossal nucleus. It is suggested that these structures are part of, or at least have direct access to, the motor coordination mechanism of phonation. Complete inhibition of phonation was obtained from the raphe and raphe-near reticular formation.Abbreviations Ab
nucl ambiguus
- APt
area praetectalis
- BC
brachium conjunctivum
- BP
brachium pontis
- Cb
cerebellum
- CC
corpus callosum
- Cd
nucl. caudatus
- Cf
nucl. cuneiformis
- Cel
nucl. centralis lateralis
- Cl
claustrum
- CM
centrum medianum
- Cn
nucl. cuneatus
- Co
nucl. cochlearis
- CoI
colliculus inferior
- CoS
colliculus superior
- CP
commissura posterior
- CPf
cortex piriformis
- CRf
corpus restiforme
- CSL
nucl. centralis superior lateralis thalami
- CT
corpus trapezoideum
- DBC
decussatio brachii conjunctivi
- DG
nucl. dorsalis tegmenti (Gudden)
- DLM
decussatio lemnisci medialis
- DPy
decussatio pyramidum
- DR
nucl. dorsalis raphae
- DV
nucl. dorsalis n. vagi
- DIV
decussatio n. trochlearis
- EP
epiphysis
- FC
funiculus cuneatus
- FL
funiculus lateralis
- FLM
fasciculus longitudinalis medialis
- FRM
formatio reticularis myelencephali
- FRP
formatio reticularis pontis
- FRPc
formatio reticularis pontis caudalis
- FRPo
formatio reticularis pontis oralis
- FRTM
formatio reticularis mesencephali
- FV
funiculus ventralis
- G
nucl. gracilis
- GC
substantia grisea centralis (periaqueductal grey)
- GL
nucl. geniculatus lateralis
- GM
nucl. geniculatus medialis
- GP
globus pallidus
- GPM
griseum periventriculare mesencephali
- GPo
griseum pontis
- Hip
hippocampus
- HL
nucl. habenularis lateralis
- H
habenula
- IP
nucl. interpeduncularis
- LC
locus coeruleus
- LD
nucl. lateralis dorsalis thalami
- Lim
nucl. limitans
- LLd
nucl. lemnisci lateralis, pars dorsalis
- LLv
nucl. lemnisci lateralis, pars ventrali
- LM
lemniscus medialis
- LP
nucl. lateralis posterior thalami
- MD
nucl. medialis dorsalis thalami
- MV
nucl. motorius n. trigemini
- NCS
nucl. centralis superior
- NCT
nucl. trapezoidalis
- NMV
nucl. mesencephalicus n. trigemini
- NR
nucl. ruber
- NSV
nucl. spinalisn. trigemini
- NTS
nucl. tractus solitarii
- NIII
nucl. oculomotorius
- NIV
nucl. trochlearis
- NVI
nucl. abducens
- NVII
nucl. facialis
- NXII
nucl. hypoglossus
- OI
oliva inferior
- OS
oliva superior
- P
nucl. posterior thalami
- PbL
nucl. parabrachialis lateralis
- PbM
nucl. parabrachialis medialis
- PC
depedunculus cerebri
- Pd
nucl. peripeduncularis
- Pg
nucl. parabigeminalis
- Pp
nucl. praepositus
- PuI
nucl. pulvinaris inferior
- PuL
nucl. pulvinaris lateralis
- PuM
nucl. pulvinaris medialis
- PuO
nucl. pulvinaris oralis
- Py
tractus pyramidalis
- Pv
nucl. principalis n. trigemini
- R Ab
nucl. retroambiguus
- RL
nucl. reticularis lateralis
- RTP
nucl. reticularis tegmenti pontis
- Sf
nucl. subfascicularis
- SGD
substantia grisea dorsalis
- SGV
substantia grisea ventralis
- SN
substantia nigra
- ST
stria terminalis
- St
subthalamus
- TRM
tractus retroflexus (Meynert)
- TSc
tractus spinocerebellaris
- Ves
nucl. vestibularis
- VL
nucl. ventralis lateralis
- VPI
nucl. ventralis posterior inferior
- VPL
nucl. ventralis posterior lateralis
- VPM
nucl. ventralis posterior medialis
- VR
nucl. ventralis raphae
- Zi
zona incerta
- II
tractus opticus
- VII
n. facialis 相似文献
102.
The mammalian neuromuscular junction has been extensively studied by different methods to understand better the biological aspects of its normal development, ageing and pathological conditions, such as disorders of neuromuscular transmission. In the present report, a new technique is described that combines confocal microscopy with the use of a vital nerve terminal dye (4-Di-2-ASP) and rhodamine-alpha-bungarotoxin to stain postsynaptic acetylcholine receptors in the same endplate. Nerve terminals in the sternomastoid muscles of living adult mice were stained with 4-Di-2-ASP, which labels intracellular compartments of the nerve terminal containing mitochondria. Slides of these muscles were viewed by confocal microscopy and images were stored on magnetic optical discs. This procedure was compatible with subsequent acetylcholine receptor staining with rhodamine-α-bungarotoxin and observation under the confocal microscope. Classical features of the adult neuromuscular junction were displayed, such as the branched-pattern distribution of the nerve terminals and receptors and their complete colocalisation. In addition, nerve fibres from intramuscular nerve branches with their neighbouring cells, nuclei and muscle fibre striations could also be visualised. We conclude that the present technique can complement existing methods of investigation of nerve terminal anatomy and pathology, particularly where preservation of 3-dimensional relationships is required and intracellular disturbances involving mitochondrial organisation, such as ageing or other degenerative disorders, may be present. 相似文献
103.
K. Keizer H. G. J. M. Kuypers 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1989,74(2):311-318
Summary An earlier retrograde double-labeling study in cat showed that up to 30% of the corticospinal neurons in the medial and anterior parts of the precruciate motor area represent branching neurons which project to both the spinal cord and the reticular formation of the lower brain stem. These neurons were found to be concentrated in the rostral portion of the motor cortex, from where axial and proximal limb movements can be elicited. In the present study the findings in the macaque monkey are reported. The fluorescent retrograde tracer DY was injected unilaterally in the spinal cord at C2 and the fluorescent tracer FB was injected ipsilaterally in the medial tegmentum of the medulla oblongata. In the contralateral hemisphere large numbers of single DY-labeled corticospinal neurons and single FBlabeled corticobulbar neurons were present. A substantial number of DY-FB double-labeled corticospinal neurons were also found, which must represent branching neurons projecting to both the spinal cord and the bulbar reticular formation. These neurons were present in: 1. The anterior portion of the cingulate corticospinal area in the lower bank of the cingulate sulcus; 2. The supplementary motor area (SMA); 3. The rostral part of precentral corticospinal area; 4. The upper portion of the precentral face representation area; 5. The caudal bank of the inferior limb of the arcuate sulcus; 6. The posterior part of the insula. In these areas 10% to 30% of the labeled neurons were double-labeled. The functional implications of the presence of branching corticospinal neurons in these areas is discussed.Abbreviations A
nucleus ambiguus
- AS
arcuate sulcus
- C
cuneate nucleus
- Cing. S.
cingulate sulcus
- corp. call.
corpus callosum
- CS
central sulcus
- Cx
external cuneate nucleus
- DCN
dorsal column nuclei
- dl
dorsolateral intermediate zone
- IO
inferior olive
- IP
intraparietal sulcus
- Lat. Fis.
lateral fissure
- LR
lateral reticular nucleus
- LS
lunate sulcus
- ML
medial lemniscus
- MLF
medial longitudinal fascicle
- mn
motoneuronal pool
- MRF
medial reticular formation
- Occ.
occipital pole
- P
pyramid
- PG
pontine grey
- PS
principle sulcus
- RB
restiforme body
- RF
reticular formation
- S
solitary nucleus
- SPV
spinal trigeminal complex
- STS
superior temporal sulcus
- Sup. Col.
superior colliculus
- TB
trapezoid body
- VC
vestibular complex
- vm
ventromedial intermediate zone
- III
nucleus oculomotorius
- VI
nucleus abducens
- VII
nucleus, n. facialis
- X
motor nucleus n. vagus
- XII
nucleus hypoglossus
Supported in part by grant 13-46-96 of FUNGO/ZWO (Dutch organisation for fundamental research in medicine) 相似文献
104.
The purpose of this study was twofold: 1) to attempt to replicate a previous study in which subjects were trained to produce bi-directional changes in diastolic BP as great as 10% to 15% of baseline, and 2) to determine whether the same subjects could acquire such a BP response under conditions of induced muscle tension. A 2x3 design was used in which 24 subjects were randomly assigned to one of two training procedures (feedback vs no feedback), and one of three muscular tension conditions. Acquisition took place over 14 sessions; 7 were used to train UP and 7 were used to condition DOWN responses. Results showed that during UP training, subjects learned to raise their BP in the absence of induced tension, but not when tension was present. However, the same subjects learned to lower their BP with and without induced tension, although their performance under the tension condition was only marginally reliable. 相似文献
105.
U. Sławin´ska F. Tyc˘ S. Kasicki R. Navarrete G. Vrbová 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(2):193-201
After partial denervation, the remaining motor units (MUs) of adult fast extensor digitorum longus muscle (EDL) expand their
peripheral field. The time course of this event was studied using tension measurement and recordings of electromyographic
(EMG) activity. The results show that after section of the L4 spinal nerve, when only 5.3 ± 0.63 of the 40 MUs normally supplying
EDL muscle remain, the force of individual motor units starts to increase between the 1st and 2nd week after the operation
and continues to do so for a further week. The drastic reduction of the number of motoneurones supplying the fast EDL leads
to an increase in activity of the remaining MUs. In the 1st week after partial denervation, there was a sharp increase in
the EMG activity of remaining motor units. During the next 12 days, this increase became less marked, but EMG activity remained
nevertheless significantly higher than that of the unoperated EDL muscle. Many MUs became tonically active during posture.
The EMG activity pattern during locomotion was also altered, so that the burst duration was positively correlated with the
step cycle duration. Moreover, shortly after partial denervation, the interlimb coordination was disturbed but returned to
its original symmetrical use 1–2 weeks later.
Received: 17 September 1996 / Accepted: 3 November 1997 相似文献
106.
Stinear CM Walker KS Byblow WD 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,139(1):101-105
Using transcranial magnetic stimulation (TMS) over the contralateral motor cortex, motor evoked potentials (MEPs) were recorded
from resting abductor pollicis brevis (APB) and first dorsal interosseous (FDI) muscles of eight subjects while they either
rested or produced one of six levels of force with the APB ipsilateral to the TMS. F-waves were recorded from each APB at
rest in response to median nerve stimulation while subjects either rested or produced one of two levels of force with their
contralateral APB. Contraction of the APB ipsilateral to TMS produced facilitation of the MEPs recorded from resting APB and
FDI muscles contralateral to TMS but did not modulate F-wave amplitude. Negligible asymmetries in MEP facilitation were observed
between dominant and subdominant hands. These results suggest that facilitation arising from isometric contraction of ipsilateral
hand muscles occurs primarily at supraspinal levels, and this occurs symmetrically between dominant and subdominant hemispheres.
Electronic Publication 相似文献
107.
Changes in muscle responses to stimulation of the motor cortex induced by peripheral nerve stimulation in human subjects 总被引:9,自引:0,他引:9
Ridding MC Brouwer B Miles TS Pitcher JB Thompson PD 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,131(1):135-143
The aim of this study was to determine whether prolonged, repetitive mixed nerve stimulation (duty cycle 1 s, 500 ms on-500 ms off, 10 Hz) of the ulnar nerve leads to a change in excitability of primary motor cortex in normal human subjects. Motor-evoked potentials (MEPs) generated in three intrinsic hand muscles [abductor digiti minimi (ADM), first dorsal interosseous (FDI) and abductor pollicis brevis (APB)] by focal transcranial magnetic stimulation were recorded during complete relaxation before and after a period of prolonged repetitive ulnar nerve stimulation at the wrist. Transcranial magnetic stimuli were applied at seven scalp sites separated by 1 cm: the optimal scalp site for eliciting MEPs in the target muscle (FDI), three sites medial to the optimal site and three sites lateral to the optimal stimulation site. The area of the MEPs evoked in the ulnar-(FDI, ADM) but not the median-innervated (APB) muscles was increased after prolonged ulnar nerve stimulation. Centre of gravity measures demonstrated that there was no significant difference in the distribution of cortical excitability after the peripheral stimulation. F-wave responses in the intrinsic hand muscles were not altered after prolonged ulnar nerve stimulation, suggesting that the changes in MEP areas were not the result of stimulus-induced increases in the excitability of spinal motoneurones. Control experiments employing transcranial electric stimulation provided no evidence for a spinal origin for the excitability changes. These results demonstrate that in normal human subjects the excitability of the cortical projection to hand muscles can be altered in a manner determined by the peripheral stimulus applied. 相似文献
108.
The purpose of this experiment was to study the brain potentials generated during spatial tasks related to the “schema corporel” (a mental map of sensory-motor relationships). Seven right-handed subjects performed a choice reaction-time task (Experiment 1), in which the spatial position of a visual stimulus (right or left of a fixation point) was varied independently of the spatial position of the response (right or left hand). The subjects also made self-paced extensions and flexions of the right and left index fingers (Experiment 2). Experiments 1 and 2 were performed with the hands both crossed and uncrossed. Spatio-temporal maps showed that the P300 component elicited by the choice RT situation in Experiment 1 was largest ipsilateral to the hand involved in the response, whether or not the hands were crossed. The later part of the pre-movement potentials during Experiment 2 and the motor potential were significantly larger contralateral to the moving hand under all conditions. Thus this pattern of lateralization can be attributed to the superimposition of a bilateral P300 wave on the asymmetrical motor potential. This suggests that distinct neuronal populations are involved in the generation of these two components. P300 latency and RT reflected the spatial conflict: both were longer when the stimulus and response were on opposite sides than when they were on the same side, even when the hands were crossed. However, the average P300 latency was not increased when the hands were crossed, whereas the average RT was substantially increased. Since the additional time required for programming the movement in the crossed hand situation had no effect on P300 generation, we infer that the P300 does not index this motor programming. However, P300 does reflect the stimulus-response spatial matching, since its latency was delayed by spatial conflict. 相似文献
109.
The effects of sex and stock on a task of motor competence (balancing on a rod) were studied in Long-Evans, Sprague-Dawley and Wistar rats reared in large and small litters. The data indicated significant sex and stock effects but no effects of rearing condition. Although no nutritional effect was found on this task, the data suggest that stock differences should receive greater attention particularly with regard to the possibilities that such differences provide for the identification and analysis of a broad spectrum of effects. 相似文献
110.
The influence of motor responding and typical psychophysiological tasks on heart rate was tested by manipulating motor requirements of reaction time (RT) and time estimation (TE) tasks. Thirty-four volunteers were assigned randomly to four groups. Two groups squeezed a hand dynamometer at the start of a trial and the other two groups squeezed at the finish of the trial. The force of the squeeze was also manipulated: either 3 kg (3) or 7 kg (7). The four groups were Start 3, Start 7, Finish 3, and Finish 7. All subjects participated in the TE and RT tasks. The dependent variables were measurements of forearm flexor muscle tension, heart rate and skin conductance. It was found that the manipulations of when and with what force a person squeezed the dynamometer resulted in reliable group differences in muscle tension. The magnitude of acceleratory components of the triphasic (acceleration-deceleration-acceleration) cardiac response was amplified by tension. The magnitude of the deceleratory component seemed to depend on both muscle tension and stimulus processing. Except for the magnitude of the response-bound deceleration, RT and TE produced very similar heart rate responses, and skin conductance did not differ among groups. The data were interpreted as providing evidence that motor response acts as an amplifier for the phasic HR produced by common psychological paradigms. 相似文献