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991.
Guimerá Martín-Neda F García Bustínduy M Noda Cabrera A Sánchez González R García Montelongo R 《Journal of the American Academy of Dermatology》2004,50(1):124-126
A variety of tumors develop or exacerbate during pregnancy and it is well known that a noticeable increase of eccrine activity occurs in this period. Eccrine poroma is a benign neoplasm that originates from the eccrine sweat gland. The development of this tumor during pregnancy is extremely infrequent. We report a rare case of rapidly growing eccrine poroma in an unusual location (the nose) in a pregnant woman. 相似文献
992.
García-Bravo M López-Gómez S Segurado-Rodríguez MA Morán-Jiménez MJ Méndez M de Salamanca RE Fontanellas A 《Archives of dermatological research》2004,296(3):139-140
Hypertrichosis is a common feature in cutaneous porphyrias, characterized by high accumulation of photoreactive porphyrins. Photothermolysis induced by noncoherent light (755–1200 nm) and energy fluence of 42 J/cm2 was applied to a patient with hepatoerythropoietic porphyria. Hypertrichosis was almost completely removed after seven sessions without development of skin lesions. 相似文献
993.
Quevedo J Vianna MR Martins MR Barichello T Medina JH Roesler R Izquierdo I 《Behavioural brain research》2004,154(2):339-343
We studied the involvement of hippocampal protein synthesis-, PKA-, and MAP kinase-dependent processes in short- (STM) and long-term memory (LTM) for inhibitory avoidance task. Fifteen minutes before or immediately after training rats received intrahippocampal infusions of vehicle, the protein synthesis inhibitor anisomycin, the PKA inhibitor Rp-cAMPs or the MAPKK inhibitor PD098059. The results show that STM recruits PKA and MAPK, whereas, LTM depends on PKA activity and protein synthesis during the early post-training period. 相似文献
994.
Dimov J Capello OJ Caso de Leveratto B Neuman V Retondano RA Silvani de Capello SM Etchegoyen RH 《Vertex (Buenos Aires, Argentina)》2004,15(57):222-226
Our work is based on the application of psychoanalytic techniques, in order to unveil this cultural phenomenon called tango, related with sexuality and unconscious processes. As a way of introduction, it deals with a brief theory of the birth of tango, the possible terminological source of its name, its main creators and interpreters, as well as the chronological classification into the first wave tangos, Guardia Vieja, and the newer wave tangos, Guardia Nueva. The former ones were awash with festive themes of the centennial years, expressed in behaviors that denote sexuality and love, whereas the latter ones, expose the great bewilderment of the thirties' crisis, due to the imminent downfall of the country, the denunciation of materialism, the crumbling of ideas; which led up to feelings of utter pessimism, loneliness and abandonment. From this point onwards, through the use of techniques provided by psychoanalysis applied to tango lyrics, we are able to unravel the unconscious processes of the drama of its characters; the immigrant, hopeful and at same time nostalgic for the loss of his mother country; the porteno -urban man from Buenos Aires city- who, overwhelmed by immigrants, has to give way to the new compatriots; the inland inhabitant, who was dragged to the city because of the new conditions of rural work; and finally the conventillo, tenement house, as a melting pot that fulfilled the integration of these groups. Like in a painter's palette, which contains various colors and shades, the interpretations about nostalgia, grief and loneliness become apparent, along with the father-son rivalry, the conflict with the absent mother, the relationship between sexes, male chauvinism, infatuation, identity, the fear of death, the rebirth to a new life, the passage from gaucho to guapo, from a shrewd horseman to a daring, bullying braggart. 相似文献
995.
996.
Neutralization of the chemokine CXCL10 enhances tissue sparing and angiogenesis following spinal cord injury 总被引:3,自引:0,他引:3
Glaser J Gonzalez R Perreau VM Cotman CW Keirstead HS 《Journal of neuroscience research》2004,77(5):701-708
After spinal cord injury, there is a chemoattractant-mediated inflammatory response that is associated with secondary degeneration. The chemoattractant CXCL10 recruits CD4 Th1 cells via the CXCR3A receptor and inhibits growth and chemotaxis of endothelial cells via the CXCR3B receptor. To test the hypothesis that CXCL10 inhibits angiogenesis following spinal cord injury, we assayed the brainstems and spinal cords of spinal cord-injured mice treated with anti-CXCL10 antibodies for expression of angiogenesis-associated genes and quantified blood vessels within their spinal cords. Brainstem microarray analysis indicated eight angiogenesis-associated genes that had significantly higher expression levels in the treated mice than in the untreated mice. Ribonuclease protection assays of the spinal cords showed a significant increase in eight angiogenesis-associated genes in treated animals compared with untreated animals. Histological analysis of the spinal cords of treated and untreated mice showed a significant increase in the number of blood vessels in treated animals. We conclude that CXCL10 plays a critical role in vasculature remodeling following spinal cord injury and that angiogenesis is enhanced following anti-CXCL10 treatment of spinal cord injuries. Improved blood flow and oxygen supply to the injury site may contribute to the functional improvement associated with this treatment. 相似文献
997.
998.
Kulik A Nakadate K Hagiwara A Fukazawa Y Luján R Saito H Suzuki N Futatsugi A Mikoshiba K Frotscher M Shigemoto R 《The European journal of neuroscience》2004,19(8):2169-2178
Among various types of low- and high-threshold calcium channels, the high voltage-activated P/Q-type channel is the most abundant in the cerebellum. These P/Q-type channels are involved in the regulation of neurotransmitter release and in the integration of dendritic inputs. We used an antibody specific for the alpha1A subunit of the P/Q-type channel in quantitative pre-embedding immunogold labelling combined with three-dimensional reconstruction to reveal the subcellular distribution of pre- and postsynaptic P/Q-type channels in the rat cerebellum. At the light microscopic level, immunoreactivity for the alpha1A protein was prevalent in the molecular layer, whereas immunostaining was moderate in the somata of Purkinje cells and weak in the granule cell layer. At the electron microscopic level, the most intense immunoreactivity for the alpha1A subunit was found in the presynaptic active zone of parallel fibre varicosities. The dendritic spines of Purkinje cells were also strongly labelled with the highest density of immunoparticles detected within 180 nm from the edge of the asymmetrical parallel fibre-Purkinje cell synapses. By contrast, the immunolabelling was sparse in climbing fibre varicosities and axon terminals of GABAergic cells, and weak and diffuse in dendritic shafts of Purkinje cells. The association of the alpha1A subunit with the glutamatergic parallel fibre-Purkinje cell synapses suggests that presynaptic channels have a major role in the mediation of excitatory neurotransmission, whereas postsynaptic channels are likely to be involved in depolarization-induced generation of local calcium transients in Purkinje cells. 相似文献
999.
Blanco-Centurion C Gerashchenko D Salin-Pascual RJ Shiromani PJ 《The European journal of neuroscience》2004,19(10):2741-2752
The hypocretin neurons have been implicated in regulating sleep-wake states as they are lost in patients with the sleep disorder narcolepsy. Hypocretin (HCRT) neurons are located only in the perifornical region of the posterior hypothalamus and heavily innervate pontine brainstem neurons, such as the locus coeruleus (LC), which have traditionally been implicated in promoting arousal. It is not known how the hypocretin innervation of the pons regulates sleep-wake states as pontine lesions have never been shown to increase sleep. It is likely that in previous studies specific neurons were not lesioned. Therefore, in this study, we applied saporin-based neurotoxins to the dorsolateral pons and monitored sleep in rats. Anti-dopamine-beta-hydroxylase-saporin killed the LC neurons but sleep was affected only during a two hour light-dark transition period. Application of hypocretin2-saporin killed fewer LC neurons relative to other adjacent neurons. This occurred because the LC neurons possess the hypocretin receptor 1 but the ligand hypocretin 2 binds to this receptor with less affinity relative to the hypocretin receptor 2. The hypocretin2-saporin lesioned rats compared to controls had increased sleep during the dark period and displayed increased limb movements during REM sleep. None of the lesioned rats had sleep onset REM sleep periods or cataplexy. We conclude that the hypocretin innervation to the pons functions to awaken the animal when the lights turn off (via its innervation of the LC), sustains arousal and represses sleep during the rest of the night (via a wider innervation of other pontine neurons), and modulates muscle tone. 相似文献
1000.
In the domestic chicken, providing visual barriers for a brief period early in life has been found to improve spatial memory [R. Freire et al. (2004)Animal Behaviour, 67, 141-150]. In the present study we compared the structure of neurons in the hippocampus and neostriatum in chicks reared with or without visual barriers. From 8 to 16 days of age, chicks were reared in pens either with two wooden screens (Treatment E) or with no screens (Treatment C). At 16 days of age, chicks were anaesthetized, perfused intracardially and brain samples collected and stained using a Golgi-Cox technique. Morphometric analysis revealed that the multipolar projection neurons of Treatment E chicks had longer dendrites (ANOVA, F(1,14) = 7.4, P < 0.05) and had more spines per 20 micro m of dendrite (SLD; ANOVA, F(1,14) = 10.6, P < 0.01) than those of Treatment C chicks. By contrast, no evidence was found that rearing treatment differentially influences dendrite length or SLD in the neostriatum, suggesting that the above environment-induced changes may be specific to the hippocampus. Multipolar projection neuron dendrites of the right hemisphere were longer (ANOVA, F(1,14) = 36.4, P < 0.0001) and had more spines (ANOVA, F(1,14) = 8.8, P < 0.05) than dendrites of the left hemisphere, supporting previous findings that the right hemisphere of chickens is predominantly involved in spatial processing. We conclude that the chicken provides a useful model for the study of developmental plasticity in brain and behaviour, partly because the possibility of rearing chicks in isolation and imprinting them on an artificial object provides a means of accurately manipulating early experience. 相似文献