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1.
2.
21 d-6°头低位卧床期间运动训练对动态姿态平衡的影响 总被引:1,自引:0,他引:1
目的探讨21 d-6°头低位卧床和卧床运动训练对动态姿态平衡和控制功能的影响. 方法 10名健康男性青年被试者分为卧床对照组和卧床训练组,每组5人,卧床期间训练组每天进行2次、每次30 min逐级增加负荷的头低位功率自行车训练;分别于卧床前和卧床后21 d进行了动态姿态平衡和双膝等速肌力的测试. 结果与卧床前相比,对照组动态本体感觉得分和运动控制适应能力明显降低,双膝相对峰力矩明显降低,同时伴有腘绳肌与股四头肌峰力矩屈/伸比值的明显增加;训练组动态本体感觉得分和运动控制适应能力明显高于对照组,而腘绳肌与股四头肌峰力矩屈/伸比值无明显改变. 结论 21 d-6°头低位卧床运动训练能够明显改善卧床后动态姿态平衡及其动态运动适应功能. 相似文献
3.
以ESR、UV和IR表征Cu(2+)离子与PVAC的配位反应。根据CUCl2·2H2O乙醇溶液与PVAc-CuCl2·2H2O乙醇溶液的电导率差值随Cu(2+)离子摩尔浓度变化的明显转析点得知,1个Cu(2+)离子大约能与PVAc4个链节单元配位。证实MMA在Cu(Ⅱ)-PVAc配合物/Na2SO3体系的聚合体是无规PMMA,得率为70%。讨论了MMA在Cu(Ⅱ)-PVAc配合物/Na2SO3体系络合催化引发下的游离基反应历程。 相似文献
4.
合成了4种-N(2-羟基乙基)水杨醛亚胺合铜(Ⅱ)类配合物,其结构经红外光谱、元素分析,原子吸收证实,并对其抑菌活性进行了试验。结果表明,配合物Ⅰ、Ⅱ对4种革兰氏阳性菌和一种革兰氏阴性菌有抑菌活性。 相似文献
5.
用K.S熵(一种信息熵)判别林业系统中生态和经济的协调关系,并提出了控制和改进现有林业系统的有效途径。 相似文献
6.
Patti Besuner RN MN CNS Steven Imhoff RN MSN CNP 《Newborn and Infant Nursing Reviews》2007,7(4):211-215
Complete and accurate knowledge is critical to parent decision making for families with complex and/or life-threatening fetal conditions. Comprehensive fetal centers are available to provide multidisciplinary specialized assessment, evaluation, diagnosis, and nondirectional counseling. Interventional option may include fetoscopic procedures, open fetal surgery, and ex utero intrapartum treatment. The nurse coordinator serves as the family and health care provider liaison for arrangement of services and communication of the plan of care. 相似文献
7.
Michael P. Stryker Peter H. Schiller 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1975,23(1):103-112
Summary In unrestrained animals of many species, electrical stimulation at sites in the superior colliculus evokes motions of the head and eyes. Collicular stimulation in monkeys whose heads are rigidly fixed is known to elicit a saccade whose characteristics depend on the site stimulated and are largely independent of electrical stimulation parameters and initial eye position.This study examined what role the colliculus plays in the coding of head movements. A secondary aim was to demonstrate the effects of such electrical stimulation parameters as pulse frequency and intensity. Rhesus monkeys were free to move their heads in the horizontal plane; head and eye movements were monitored. As in previous studies, eye movements evoked by collicular stimulation were of short latency, repeatable, had a definite electrical threshold, and did not depend on the initial position of the eye in the orbit. By contrast, evoked head movements were extremely variable in size and latency, had no definite electrical threshold, and did depend on initial eye position. Thus when the eyes approached positions of extreme deviation, a head movement in the same direction became more likely. These results suggest that the superior colliculus does not directly code head movements in the monkey. 相似文献
8.
Mars F Archambault PS Feldman AG 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,150(4):515-519
Recent studies have shown that the hand-pointing movements within arm's reach remain invariant whether the trunk is recruited
or not or its motion is unexpectedly prevented. This suggests the presence of compensatory arm-trunk coordination minimizing
the deflections of the hand from the intended trajectory. It has been postulated that vestibular signals elicited by the trunk
motion and transmitted to the arm motor system play a major role in the compensation. One prediction of this hypothesis is
that vestibular stimulation should influence arm posture and movement during reaching. It has been demonstrated that galvanic
vestibular stimulation (GVS) can influence the direction of pointing movements when body motion is restrained. In the present
study, we analyzed the effects of GVS on trunk-assisted pointing movements. Subjects either moved the hand to a target or
maintained a steady-state posture near the target, while moving the trunk forward with the eyes closed. When GVS was applied,
the final position of the hand was deviated in the lateral and sagittal direction in both tasks. This was the result of two
independent effects: a deviation of the trunk trajectory and a modification of the arm position relative to the trunk. Thus,
the vestibular system might be directly involved not only in the control of trunk motion but also in the arm-trunk coordination
during trunk-assisted reaching movements.
Electronic Publication 相似文献
9.
C. Strazielle P. Krémarik J.-F. Ghersi-Egea R. Lalonde 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(1):35-45
Lurcher mutant mice are characterized by massive degeneration of cerebellar Purkinje cells and granule cells and by deficits in motor
coordination. Regional brain variations of cytochrome oxidase (CO) activity were analyzed to identify those brain regions
with abnormal metabolic activity as a secondary consequence of the cerebellar atrophy and to establish the relationship between
CO activity and motor deficits. Lurcher mutants had higher CO activity in all three cerebellar deep nuclei than normal littermate controls of the same background
strain. Higher CO activity was also found in Lurcher mutants in brain regions directly connected to the cerebellum, such as the lateral vestibular nucleus, the cochlear nucleus,
the red nucleus, the ventrolateral thalamus, the dorsal raphe, the interpeduncular nucleus, and the inferior colliculus. By
contrast, there was a sharp decrease in CO activity in the inferior olive. As for brain regions not directly connected to
the cerebellum, higher CO activity was observed in the trigeminal motor nucleus and the CA1 molecular layer of the hippocampus,
which highlights probable transsynaptic alterations as a secondary consequence of cerebellar atrophy. A positive correlation
between CO activity in the red nucleus and latencies before falling in two motor-coordination tests indicates that a compensatory
increase of metabolic activity in a cerebellar efferent region is associated with improved behavior.
Received: 15 September 1997 / Accepted: 3 March 1998 相似文献
10.
Gribova A Donchin O Bergman H Vaadia E Cardoso De Oliveira S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,144(3):322-335
It has been established that repeated presentation of a transient target motion stimulus such as a constant-velocity ramp leads to the build up of steady state (SS), anticipatory smooth pursuit eye movements after two or three presentations. Each SS response is then composed of the anticipatory component of nonvisual origin, a visual component associated with the stimulus presentation and another nonvisual component that represents the decay of the response after extinction of the stimulus. Here we investigated the interactions that occur when each motion stimulus was itself a sequence containing more than one ramp component. Ramp components had a velocity of 15 degrees /s or 30 degrees /s to left or right and were separated by gaps of 200 ms duration. In an initial experiment, responses to 2-ramp stimuli were examined and compared with responses to the single-ramp stimuli from which they were constituted. We present evidence that the anticipatory, nonvisual components of the double-ramp response result from the linear summation of the nonvisual components of the responses to the constituent single-ramp components. In a 2nd experiment, we examined responses to a wide variety of 4-ramp sequences and again found evidence that, in the SS, the responses were formed from the linear summation of the constituent single-ramp components. Regression analysis performed on the velocity at onset of each ramp component indicated that this nonvisual part of the response was predictive of the upcoming ramp component. To confirm this, unexpected changes were introduced into single ramp components of the 4-ramp sequence after at least five prior presentations of the sequence had allowed a SS response to be established. Subjects continued to initiate a response to the modified component that was appropriate in velocity and direction for the corresponding part of the previous sequence and inappropriate for the newly modified stimulus. This preprogrammed response persisted unmodified for more than 170 ms after onset of the modified ramp component. In contrast, in the second presentation of the new sequence, the anticipatory component of the response was highly correlated with the SS response of the new sequence, but not with that of the prior sequence, showing that the preprogrammed response had been modified very rapidly. Similar behaviour was observed whichever of the 4-ramp components was modified, indicating that the velocity and direction of the anticipatory response to each component had been preprogrammed. The results suggest that velocity information related to at least four elements of a sequence can be temporarily stored and subsequently released with appropriate temporal order to form an anticipatory response throughout the whole sequence. 相似文献