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71.
目的 了解综合医院青少年咨客心理咨询的特点,为其心理健康教育提供依据.方法 选取2003年5月~2004年11月门诊心理咨询163人的资料进行分析.结果 该年龄段中主动求询意识占据明显优势有140人(85.9%);医学问题以神经症77人(47.2%),精神分裂11人(6.7%)列前2位;非医学问题则是厌学13人(8.0%),人际交往障碍10人(6.1%)为主要求询问题;性别与求询问题间亦有一定相关性.结论 综合医院青少年心理咨询以医学问题为主,非医学问题并存,应注意社会支持系统的完善. 相似文献
72.
T. T. Khater K. J. Quinn J. Pena J. F. Baker B. W. Peterson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,94(1):16-32
Latencies of normal and adapted feline vestibulo-ocular reflex (VOR) were studied in five cats by applying ± 20°/s horizontal head velocity steps (4000°/s2 acceleration) and measuring the elicited horizontal or vertical reflex eye responses. Normal VOR latency was 13.0 ms ± 1.9 SD. Short-term adaptation was then accomplished by using 2 h of paired horizontal sinusoidal vestibular stimulation and phase-synchronized vertical optokinetic stimulation (cross-axis adaptation). For long-term adaptation, cats wore ×0.25 or ×2.2 magnifying lenses for 4 days. The cats were passively rotated for 2 h/day and allowed to walk freely in the laboratory or their cages for the remainder of the time. The latency of the early (primary) adaptive response was 15.2ms±5.2 SD for crossaxis adaptation and 12.5 ms±3.9 SD for lens adaptation. This short-latency response appeared within 30 min after beginning the adaptation procedure and diminished in magnitude overnight. A late (secondary) adaptive response with latency of 76.8 ms±7.0 SD for cross-axis adaptation and 68.1 ms±8.8 SD for lens adaptation appeared after approximately 2 h of adaptation. It had a more gradual increase in magnitude than the primary response and did not diminish in magnitude overnight. These data suggest that brainstem VOR pathways are a site of learning for adaptive VOR modification, since the primary latency is short and has a similar latency to that of the normal VOR. 相似文献
73.
Male and female prepubertal rats, like many primate species, differ in the frequency with which they engage in social play (play-fighting); males engage in more social play than females. This sex difference in the rat has been found to be under the control of gonadal hormones acting during the neonatal period. In the present study we examined the effects of lesions of the amygdala, a prominent neuroendocrine control area, on the play-fighting of male and female prepubertal rats. Bilateral, electrolytic lesions and sham control treatments were made at 21 or 22 days of age and the animals were then observed daily in intact groups between 26 and 40 days of age. Amygdaloid lesions suppressed social play in male rats to levels that were indistinguishable from those of control females. In contrast to males, amygdaloid lesions had no effect on the social play of females. Sex differences in the anatomy and physiology of the amygdala are discussed as a possible explanation of its apparent differential influence on the social play of male and female prepubertal rats. 相似文献
74.
C. Pfeiffer V. I. Kapel'ko F. Z. Meerson 《Bulletin of experimental biology and medicine》1976,82(1):964-967
The original amplitude of contraction of strips of myocardium determined the inotropic response to paired stimulation. The higher the initial amplitude, the lower the degree of potentiation and the higher the degree of restitution of contraction. For equal amplitude, the degree of potentiation of myocardial contraction of exercise-adapted rats was greater and the degree of restitution smaller than in the control. These changes probably reflect changes in the ion transport system of the myocardial cells.Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 780–782, July, 1976. 相似文献
75.
Maria-Izabel Almeida-Silveira Chantal Pérot Francis Goubel 《European journal of applied physiology》1996,72(3):261-266
The aim of this study was the analysis of neurophysiological, mechanical and histochemical parameters to demonstrate muscle adaptation with training. If the parameters studied were to show correlated changes, it would be possible to propose that the neural and the muscle components of motor units are both affected by the training programme used. The training consisted of repeated stretch-shortening cycles known to use extensively fast fibres. After the training period electromyographical reflex activities of the ankle plantar-flexors were recorded in awake rats and then mechanical and histochemical measurements were made on isolated soleus muscles of the control and trained rats. The reflexes studied were the H-response to electrical stimulation of the sciatic nerve and the T-response to an Achilles tendon tap. The H-response analysis indicated a decrease in reflex excitability of the trained muscles. The trained soleus muscle also presented a higher contractility as demonstrated by significantly smaller twitch contraction times and higher maximal velocities of shortening measured during tetanic contractions. The reflex and contractile muscle changes were accompanied by relative increases in the number of type II fibres. The T-response was not significantly modified by training despite the decrease in motoneuron excitability demonstrated by the decrease in H-response. This would suggest that the peripheral components of the reflex pathway such as tendon stiffness and/or spindle sensitivity might be modified by training. This would imply that both the motor and the sensory parts of a muscle are affected by training. 相似文献
76.
Roger Rick Adolf Dörge Uri Katz Richard Bauer Klaus Thurau 《Pflügers Archiv : European journal of physiology》1980,385(1):1-10
The effect of saline adaptation on the intracellular Na, K, Cl, P concentrations and dry weight content of the toad skin epithelium (Bufo viridis) was studied using the technique of electron microprobe analysis. The measurements were performed on isolated abdominal skins either directly after dissection or after additional incubation in Ussing-type chambers.Adaptations of the toads to increasing NaCl concentrations for 7 days resulted in increased blood plasma osmolarity and a parallel increase in the cellular electrolyte, P and dry weight concentrations of the epithelium, the K increase representing the most significant fraction of the intracellular osmolarity increase. No evidence was obtained to show that the nucleus and cytoplasm reacted differently from each other and all living epithelial cell types basically showed the same response.Incubation of the isolated skins under control conditions showed a drastic inhibition of the transepithelial Na transport after adaptation to high salinities. In spite of the large variations in the transport rate almost identical intracellular electrolyte concentrations were observed. In tap water adapted toads the average cellular concentrations were 8.8 mmole/kg wet weight for Na, 109.6 for K, 41.5 for Cl, and 135.3 for P, respectively. Incubation of the skin with Ringer's solution of different osmolarities demonstrated that the epithelial cells are in osmotic equilibrium with the inner bathing solution. The results are consistent with the view that the osmotic adaptation is mainly accomplished by the movement of water.This work was supported by grants from the Deutsche Forschungsgemeinschaft and the Stiftung Volkswagenwerk 相似文献
77.
S. Liendl C. J. Lauer R. M. Hoffmann 《Somnologie - Schlafforschung und Schlafmedizin》2004,8(3):67-70
Summary
Question of the study Sleep logs are common tools in sleep research and clinical routine. Usually sleep logs have to be completed during a 2-week
period, with the first week serving as an adaptation to the instrument itself. In the present study, we investigated whether
there is indeed such an adaptation bias or not.
Patients and methods A total of 236 chronically sleep-disordered outpatients completed the standardized sleep log ‘Abend-Morgen-Protokoll’ during
a 2-week pre-screening period prior to the first visit in our sleep ambulance. Two sets of items were established, the ‘instrumental’
and the ‘therapeutic’ set. The respective ratings of the first and second week (week A, B) were compared to evaluate clinically
relevant changes.
Results The ratings of several ‘instrumental’ items significantly differed between week A and B. However, these changes—on average—were
only marginal and therefore of little clinical importance. Regarding the ‘therapeutic’ set of items, no systematic variations
could be ascertained over the assessment period.
Conclusion The present investigation could not confirm the presence of adaptation biases (instrumental, therapeutic) in a large sample
of chronically sleep-disordered outpatients. Therefore, we consider a 1-week pre-screening period via sleep log as sufficient
for the diagnostic process in these patients.
相似文献
78.
Dr. J. H. T. Bates G. N. Maksym D. Navajas B. Suki 《Annals of biomedical engineering》1994,22(6):674-681
The mechanical properties of lung tissue are important contributors to both the elastic and dissipative properties of the
entire organ at normal breathing frequencies. A number of detailed studies have shown that the stress adaptation in the tissue
of the lung following a step change in volume is very accurately described by the functiont
−k for some small positive constantk. We applied step increases in length to lung parenchymal strips and found the ensuing stress recovery to be extremely accurately
described byt
−k over almost 3 decades of time, despite the quasi-static stress-length characteristics of the strips being highly nonlinear.
The corresponding complex impedance of lung tissue was found to have a magnitude that varied inversely with frequency. We
note that this is highly reminiscent of a phenomenon known as 1/f noise, which has been shown to occur ubiquitously throughout the natural world. 1/f noise has been postulated to be a reflection of the complexity of the system that produces it, something like a central limit
theorem for dynamic systems. We have therefore developed the hypothesis that thet
−k
nature of lung tissue stress adaptation follows from the fact that lung tissue itself is composed of innumerable components
that interact in an extremely rich and varied manner. Thus, although the constantk is no doubt determined by the particular constituents of the tissue, we postulate that the actual functional form of the
stress adaptation is not. 相似文献
79.
Mitochondrial DNA sequences reveal close relationships between social parasitic ants and their host species 总被引:2,自引:0,他引:2
In the tribe Leptothoracini, the phylogenetic relationship of socially parasitic ants (Doronomyrmex kutteri, D. goesswaldi and Harpagoxenus sublaevis) and their host species Leptothorax acervorum has been controversial. Even more controversial is the relationship between the socially parasitic ant Chalepoxenus muellerianus and its host species Leptothorax unifasciatus, L. nigriceps, L. interruptus and L. recedens. On the basis of morphological, ecological and ethological criteria it has been argued that socially parasitic ants and their respective hosts always evolved from common ancestors, and hence it has been postulated that these species should be included in common taxonomical groups. This would require the division of the tribe Leptothoracini into two subgroups, one comprising the subgenus Leptothorax (s. str.) and the other the subgenus Myrafant, together with their respective parasitic genera. We have used the polymerase chain reaction (PCR) to compare a 360-bp sequence of the mitochondrial cytochrome b gene of 14 species belonging to the tribe Leptothoracini and an outgroup species Tetranorium impurum (Tetramoriini). The results generally agree with the morphological studies which suggest that a common ancestral species differentiated into host and parasite species. This relationship is very obvious within the Leptothorax (s. str.) group but less pronounced in the species belonging to the Myrafant group. Leptothorax (Temnothorax) recedens shows a greater sequence divergence than the outgroup species T. impurum. 相似文献
80.
儿童退缩和同伴关系的相关 总被引:6,自引:2,他引:6
目的:用元分析方法对近20年关于儿童退缩和同伴关系相关的研究结果进行总结。方法:用多水平分析技术对儿童退缩和同伴接受的相关、退缩和同伴拒绝相关的研究结果进行总结分析。结果:儿童退缩和同伴接受之间有显著的负相关关系,退缩和同伴拒绝之间有低度的非负相关关系,各研究结果之间的变异显著。结论:退缩导致儿童不良的同伴关系。 相似文献