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ObjectiveTo determine changes in saliva sonic hedgehog (Shh) and in taste dysfunction before and after oral theophylline treatment.DesignShh was measured in parotid saliva of both normal subjects and patients with taste dysfunction of multiple etiologies by use of a sensitive spectrophotometric ELISA assay. Taste dysfunction was defined clinically by both subjective inhibition of taste function (including acuity loss) and impaired gustometry.ResultsTheophylline treatment increased patient saliva Shh and improved taste dysfunction both subjectively and by gustometry.ConclusionsBy use of these systematic clinical measurements theophylline can be demonstrated to increase saliva Shh and improve taste dysfunction. These results are consistent with saliva Shh acting as a taste bud growth factor which stimulates stem cells of taste buds to initiate development and perpetuation of taste bud receptors. Measurements of saliva Shh provide an important marker for the presence of taste dysfunction and in the improvement by theophylline treatment.  相似文献   
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Objective To explore the effect of expression of protein kinase C receptor l(RACKl) induced by lipopolysaccharide (LPS) on Sonic hedgehog(SHH) signaling pathway in rat puhnonary microvascular endothelial cells (RPMVEC). Methods The healthy male SPF grade SD rat with 100-120 g body weight were gotten from the laboratory animal center of Annui province. Using immunocytochemistry method, the expression of RACK 1 protein in RPMVECs was detected, cultured RPMVECs were randomly divided into different groups as LPS dose-dependent group, SAG(smoothened Agonist, a SHH signaling pathway specific agonist) dose-dependent group, LPS time-dependent group, SAG time-dependent group and LPS+SAG group. In LPS dose-dependent groups, RPMVECs were cultured with 0.1, 1, 10 mg/L LPS for 8 h. In LPS time-dependent groups, RPMVECs were cultured with 10 mg/L LPS for 0, 2, 4, 8, 12, 24 h. In SAG dose-dependent groups, RPMVECs were cultured with 0.1, 1, 10 u, mol/L for 8 h. In SAG time-dependent groups, RPMVECs were cultured with 1 u, mol/L SAG for 0, 2, 4, 8, 12, 24 h. In LPS+SAG group, RPMVECs were cultured with 1 u. mol/L SAG 8 h after 10 mg/L LPS treatment for 1 h. In addition, blank group, LPS group and SAG group were set for control. Western blot were used to detect the level of RACK1 and RT-PCR were used to detect the expression of GLI-1 mRNA after intervention. Results Immunocytochemistry revealed that RACK1 were present in RPMVEC. 1. In LPS dose-dependent groups (0, 0.1, 1, 10 mg/L), the level of RACK 1 elevated as LPS dose increased correspondingly with inter-group difference (P<0.05); the relative expression levels of GLI-1 mRNA were (1.109 ± 0.063), (1.039 ± 0.135), (0.813 ± 0.066), (0.770 ± 0.105), (1 mg/L vs. 10 mg/L, P>0.05; the rest P<0.05). In LPS time-dependent groups, the relative expression level of RACK1 at 2 h (0.370 ± 0.010) was higher than that at 0 h (0.329 ± 0.008), peaked at 12 h (1.296 ± 0.048), and compared with 0 h, there was significant differences (F=l 272.204, P<0.05). The relative expression level of GLI-1 mRNA was decreased at 2 h (0.929 ± 0.007), and compared with 0 h(1.089 ± 0.042), there was significant differences (F=306.609, /><0.05). 2. In SAG dose-dependent groups, there was no significant difference in level of RACK1 between groups(all P>0.05). The relative expression levels of GLI-1 mRNA were (1.109 ± 0.063), (1.169±0.052), (3.468 ±0.128), (3.434±0.054), (0 μ.mol/L vs. 0.1 μ.mol/L and l μmol/L vs. 10 μ.mol/L, P>0.05, the rest P<0.05). Among SAG time-dependent groups, there was no significant difference in levels of RACK1 protein(P>0.05). The relative expression level of GLI-1 mRNA increased at 2 h (3.027 ± 0.065), and compared with 0 h (2.651 ± 0.123), there was significant differences (F= 132.841, P<0.05). 3. In LPS+SAG intervention groups, the expression of RACK1 was lower than that in LPS group (0.831 ± 0.040 vs. 1.189 ± 0.149, P<0.05), and the expression of GLI-1 mRNA was higher than that in LPS group (2.720 ± 0.130 vs. 0.796 ± 0.082, P<0.05). Conclusions The LPS up-regulates the expression of RACK 1 in RPMVECs, and the activated SHH signaling pathway can down-regulate the expression of RACK 1 induced by LPS in RPMVECs. © 2018 Chinese Medical Association. All rights reserved.  相似文献   
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The presence of growth-induced solid stresses in tumors has been suspected for some time, but these stresses were largely estimated using mathematical models. Solid stresses can deform the surrounding tissues and compress intratumoral lymphatic and blood vessels. Compression of lymphatic vessels elevates interstitial fluid pressure, whereas compression of blood vessels reduces blood flow. Reduced blood flow, in turn, leads to hypoxia, which promotes tumor progression, immunosuppression, inflammation, invasion, and metastasis and lowers the efficacy of chemo-, radio-, and immunotherapies. Thus, strategies designed to alleviate solid stress have the potential to improve cancer treatment. However, a lack of methods for measuring solid stress has hindered the development of solid stress-alleviating drugs. Here, we present a simple technique to estimate the growth-induced solid stress accumulated within animal and human tumors, and we show that this stress can be reduced by depleting cancer cells, fibroblasts, collagen, and/or hyaluronan, resulting in improved tumor perfusion. Furthermore, we show that therapeutic depletion of carcinoma-associated fibroblasts with an inhibitor of the sonic hedgehog pathway reduces solid stress, decompresses blood and lymphatic vessels, and increases perfusion. In addition to providing insights into the mechanopathology of tumors, our approach can serve as a rapid screen for stress-reducing and perfusion-enhancing drugs.  相似文献   
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Rat bone marrow-derived mesenchymal stem cells were cultured and passaged in vitro. After induction with basic fibroblast growth factor for 24 hours, passage 3 bone marrow-derived mesenchymal stem cells were additionally induced into dopaminergic neurons using three different combinations with basic fibroblast growth factor as follows: 20% Xiangdan injection; all-trans retinoic acid + glial-derived neurotrophic factor; or sonic hedgehog + fibroblast growth factor 8. Results suggest that the bone marrow-derived mesenchymal stem cells showed typical neuronal morphological characteristics after induction. In particular, after treatment with sonic hedgehog + fibroblast growth factor 8, the expressions of nestin, neuron-specific enolase, microtubule- associated protein 2, tyrosine hydroxylase and vesicular monoamine transporter-2 in cells were significantly increased. Moreover, the levels of catecholamines in the culture supernatant were significantly increased. These findings indicate that Xiangdan injection, all-trans retinoic acid + glial-derived neurotrophic factor, and sonic hedgehog + fibroblast growth factor 8 can all induce dopaminergic neuronal differentiation from bone marrow-derived mesenchymal stem cells. In particular, the efficiency of sonic hedgehog + fibroblast growth factor 8 was highest.  相似文献   
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Bone marrow stromal cells (MSCs) improve neurologic recovery after middle cerebral artery occlusion (MCAo). To examine whether in vivo blockage of the endogenous sonic hedgehog (Shh) pathway affects grafted MSC-induced neurologic benefits, MCAo mice were administered: vehicle (control); cyclopamine (CP)— a specific Shh pathway inhibitor; MSC; and MSC and cyclopamine (MSC-CP). Neurologic function was evaluated after MCAo. Electron microscopy and immunofluorescence staining were employed to measure synapse density, protein expression of tissue plasminogen activator (tPA), and Shh in parenchymal cells in the ischemic boundary zone (IBZ), respectively. Marrow stromal cell treatment significantly enhanced functional recovery after ischemia, concurrent with increases of synaptophysin, synapse density, and myelinated axons along the IBZ, and significantly increased tPA and Shh expression in astrocytes and neurons compared with control. After treatment with MSC-CP or CP, the above effects were reversed. Co-culture of MSCs with cortical neurons confirmed the effect of Shh on MSC-mediated neurite outgrowth. Our data support the hypothesis that the Shh pathway mediates brain plasticity via tPA and thereby functional recovery after treatment of stroke with MSCs.  相似文献   
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