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141.
Hibernation is a physiological state characterized by a dramatic reduction in various functions, such as body temperature, heart rate, and metabolism. The hippocampus is thought to be important for regulation of the hibernation bout because it remains electrophysiologically active throughout this extremely depressed state. The question arises as to what neuronal influences act within the hippocampus during hibernation to sustain its activity. We hypothesized that histaminergic input might be an important contributor. Brain histamine is involved in functions relevant to hibernation, such as the regulation of diurnal rhythms, body temperature, and energy metabolism. Furthermore, we have previously shown that the histaminergic system appears to be activated during the hibernating state. In this study, we used receptor binding autoradiography, in situ hybridization, and GTP-gamma-S binding autoradiography to study changes in histamine receptors across the hibernation bout. We were able to demonstrate an increase in histamine H1 and H2 receptors in the hippocampus during hibernation, whereas the mRNA expression and receptor density of the inhibitory H3 receptor decreased. Histamine H3 receptors were shown to exhibit both histamine-activated and constitutive GTP-gamma-S-binding activity in the ground squirrel hippocampus, both of which decreased during hibernation, indicating a decrease in H3 receptor G-protein activation. Taken together, our results indicate that histamine may be involved in maintaining hibernation by sustaining hippocampal activity, possibly through H1 and H2 receptor activity and decreased inhibition by H3 receptors. The involvement of brain histamine, which is generally thought of as an arousal molecule, in maintaining a depressed state of the brain suggests a more general role for the amine in controlling arousal state. 相似文献
142.
Features of skin-coincubated macrophages that promote recovery from spinal cord injury 总被引:4,自引:0,他引:4
Bomstein Y Marder JB Vitner K Smirnov I Lisaey G Butovsky O Fulga V Yoles E 《Journal of neuroimmunology》2003,142(1-2):10-16
Uncontrolled inflammation is considered to exacerbate the neuronal loss that follows spinal cord trauma. However, controlled inflammation response appears to be beneficial. Skin-coincubated macrophages injected into contused spinal cord of rats resulted in improved motor recovery and reduced spinal cyst formation. The macrophages express elevated levels of cell-surface molecules CD80, CD86, CD54 and MHC-II, markers characteristic of antigen presenting cells (APCs). Additionally, skin-coincubation elevates secretion of interleukin-1 beta (IL-1 beta) and Brain-Derived Neurotrophic Factor (BDNF), and reduces secretion of tumor necrosis factor alpha (TNF-alpha). We propose that macrophages activated by skin-coincubation bolster neuroprotective immune activity in the spinal cord, making the environment less cytotoxic and less hostile to axonal regeneration. 相似文献
143.
We have analyzed results of special treatment 187 patients with cancer of a larynx T1-2N0M0. The patients were parted into four clinical groups. 45 patients of the first group have received combined treatment, including a partial resection of the larynx and preoperative radial therapy in a general dose up to 40 Gr. 47 patients of the second group have received a course of the radial therapy under the radical program in total dose 70 Gr. 63 patients of the third group have passed a course of combined treatment, including the partial resection of the larynx and pre- and postoperative radial therapy in total dose, equivalent 60 Gr of a standard procedure. 32 patients of the fourth group have passed the extremely surgical treatment (partial resection of the larynx). The obtained results speak about large efficiency of combined treatment. As contrasted to with radial therapy under the radical program quantity of relapses considerably has decreased in the field of the primary center. As contrasted to with surgical treatment statistically quantity of recurrence of disease in area of regional lymphatic nodes authentically has decreased. 相似文献
144.
Attention can profoundly shape the experience of pain. However, little is known about the neural mechanisms that support directed attention to nociceptive information. In the present study, subjects were cued to attend to either the spatial location or the intensity of sequentially presented pairs of painful heat stimuli during a delayed match-to-sample discrimination task. We hypothesized that attention-related brain activation would be initiated after the presentation of the attentional cue and would be sustained through the discrimination task. Conjunction analysis confirmed that bilateral portions of the posterior parietal cortex (intraparietal sulcus [IPS] and superior parietal lobule) exhibited this sustained activity during attention to spatial but not intensity features of pain. Analyses contrasting activation during spatial and intensity attention tasks revealed that the right IPS region of the posterior parietal cortex was consistently more activated across multiple phases of the spatial task. However, attention to either feature of the noxious stimulus was associated with activation of frontoparietal areas (IPS and frontal eye fields) as well as priming of the primary somatosensory cortex. Taken together, these results delineate the neural substrates that support selective amplification of different features of noxious stimuli for utilization in discriminative processes. 相似文献
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Cryptosporidium Pig Genotype II in Immunocompetent Man 总被引:1,自引:0,他引:1
Martin Kvá? Dana Květoňová Bohumil Sak Oleg Ditrich 《Emerging infectious diseases》2009,15(6):982-983
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Xin Y. Mei Ibrahim S. Alshaygy Oleg A. Safir Allan E. Gross Paul R. Kuzyk 《The Journal of arthroplasty》2018,33(7):2050-2056