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21.
Thalidomide is commonly used in treatment of multiple myeloma (MM). This study aimed to analyse the influence of clinical and molecular factors - single nucleotide polymorphisms (SNPs) of the CRBN gene: rs6768972 and rs1672753, on the risk of adverse effects (AEs) of thalidomide-based chemotherapy in patients with MM. The study group included 82 patients receiving CTD (thalidomide, cyclophosphamide, dexamethasone) as first line treatment. The intensity of haematological and non-haematological AEs was assessed according to the Common Terminology Criteria for Adverse Events v4.03. Multivariate analysis showed that patients with the CRBN CC genotype (rs1672753) had more than a 14-fold higher risk of peripheral polyneuropathy compared to patients with other variants of the investigated SNP [odds ratio (OR) = 14·29]. Carriers of this genotype were burdened with significantly (about 17-fold) higher risk of diarrhoea during treatment (OR = 16·67). The presence of CRBN AA (rs6768972) or TT (rs1672753) genotypes was associated with about 333-fold and 250-fold lower risk of constipation in the course of therapy (OR = 0·003; OR = 0·004, respectively). Selected CRBN SNPs may be useful in assessing the probability of AEs in the form of peripheral polyneuropathy and gastrointestinal motility disorders associated with the use of thalidomide in patients with MM.  相似文献   
22.
Stromal cell-derived factor 1 (SDF-1) plays a major role in the migration, recruitment, and retention of endothelial progenitor cells to sites of ischemic injury and contributes to neovascularization. We provide direct evidence demonstrating an important role for heme oxygenase 1 (HO-1) in mediating the proangiogenic effects of SDF-1. Nanomolar concentrations of SDF-1 induced HO-1 in endothelial cells through a protein kinase C zeta-dependent and vascular endothelial growth factor-independent mechanism. SDF-1-induced endothelial tube formation and migration was impaired in HO-1-deficient cells. Aortic rings from HO-1(-/-) mice were unable to form capillary sprouts in response to SDF-1, a defect reversed by CO, a byproduct of the HO-1 reaction. Phosphorylation of vasodilator-stimulated phosphoprotein was impaired in HO-1(-/-) cells, an event that was restored by CO. The functional significance of HO-1 in the proangiogenic effects of SDF-1 was confirmed in Matrigel plug, wound healing, and retinal ischemia models in vivo. The absence of HO-1 was associated with impaired wound healing. Intravitreal adoptive transfer of HO-1-deficient endothelial precursors showed defective homing and reendothelialization of the retinal vasculature compared with HO-1 wild-type cells following ischemia. These findings demonstrate a mechanistic role for HO-1 in SDF-1-mediated angiogenesis and provide new avenues for therapeutic approaches in vascular repair.  相似文献   
23.
Recently, the existence of a population of stem cells located in the adipose tissue has been observed. Adipose-derived stem cells are able to differentiate into multiple cell lineages including cardiac myocytes. Hence, adipose-derived cells are emerging as a new source of adult stem cells for cardiovascular repair. In this review, we discuss the basic principles of adipose-derived stem cells (types and characteristics, obtention processes, immunophenotypic characterization, and cell potency), the initial experimental studies, and the currently ongoing clinical trials.  相似文献   
24.
Ikonomov OC  Sbrissa D  Mlak K  Shisheva A 《Endocrinology》2002,143(12):4742-4754
PIKfyve is a phosphoinositide 5-kinase that can also act as a protein kinase. PIKfyve's role in acute insulin action has been suggested on the basis of its association with the insulin stimulatable phosphatidylinositol-3-kinase and the ability of acute insulin to recruit and phosphorylate PIKfyve on intracellular membranes of 3T3-L1 adipocytes. Here we have examined several classical insulin-regulated long- and short-term responses in insulin-sensitive cells expressing high levels of either active PIKfyve or kinase-dead mutants with a dominant-negative effect. Up-regulation of PIKfyve protein expression was documented in the early stages of differentiation of cultured 3T3-L1 fibroblasts into adipocytes and a kinase-dead mutant, PIKfyveDeltaK, introduced into the preadipocyte stage profoundly delayed the hormone-induced adipogenesis. Next, insulin-induced mitogenesis was markedly inhibited in HEK293 stable cell lines, inducibly expressing the dominant-negative kinase-dead PIKfyve(K1831E) mutant but not in cells expressing PIKfyve(WT). Similarly, expression of the dominant negative mutants PIKfyve(K1831E) or PIKfyveDeltaK strongly inhibited insulin-stimulated translocation of GLUT4 in 3T3-L1 adipocytes, or GLUT1-mediated glucose uptake in Chinese hamster ovary T cells expressing the human insulin receptor. Expression of PIKfyveDeltaK and PIKfyve(WT) in Chinese hamster ovary T cells decreased or increased, respectively, insulin-stimulated Akt phosphorylation at Ser473 but not at Thr308. Furthermore, a powerful inhibition of PIKfyve was documented at a very low concentration (ID(50) = 6 micro M) of the cell-permeable kinase inhibitor curcumin. When introduced into 3T3-L1 adipocytes, curcumin markedly inhibited insulin-induced GLUT4 translocation and glucose transport. Together these data indicate that PIKfyve enzymatic activity functions as a positive regulatory intermediate in insulin acute and long-term biological responses and identify Ser473 in Akt as one potential PIKfyve downstream target.  相似文献   
25.
In the present work, for the first time, the possibility of formation of CrAl2O4 was shown from the equimolar mixture of co-precipitated Al2O3 and Cr2O3 oxides under a reductive environment. The crystallographic properties of the formed compound were calculated using the DICVOL procedure. It was determined that it has a cubic crystal structure with space group Fd-3m and a unit cell parameter equal to 8.22(3) Å. The formed CrAl2O4 is not stable under ambient conditions and easily undergoes oxidation to α-Al2O3 and α-Cr2O3. The overall sequence of the phase transformations of co-precipitated oxides leading to the formation of spinel structure is proposed.  相似文献   
26.

Introduction

Traumatic brain injury (TBI) affects cardiac electrical function, and several extra-cerebral factors, including intra-abdominal pressure (IAP), might further modulate this brain-heart interaction. The purpose of this study was to investigate the impact of TBI, and of increased IAP during TBI, on cardiac electrical function as measured by vectorcardiographic (VCG) variables.

Methods

Survival, IAP and changes in VCG variables including spatial QRS-T angle and QTc interval were measured in consecutive adult patients with either isolated TBI (iTBI), or with TBI accompanied by polytrauma to the abdomen and/or limbs (pTBI). For all patients, observations were performed just after the admission to the ICU (baseline) and at 24, 48, 72 and 96 h after admission.

Results

74 patients aged 45 ± 18 were studied. 44 were treated for iTBI and 30 for pTBI. In all patients, spatial QRS-T angle and QTc interval increased after TBI (p < 0.001), relatively more so in patients with pTBI. Compared to survivors, non-survivors also ultimately had greater widening of the spatial QRS-T angle (p < 0.001), most notably just before foraminal herniation. Wider spatial QRS-T angle and longer QTc interval were also noted in patients with IAP > 12 mmHg (p < 0.001), and with right compared to left hemispheric injury (p < 0.001). ST segment level at the J point decreased 24 and 48 h after TBI in leads I, II, III, aVR, aVF, V1, V2, V3 and V6, and increased in lead V1, especially in non-survivors.

Conclusions

Spatial QRS-T angle and QTc interval increase after TBI. If foraminal herniation complicates TBI, further widening of the spatial QRS-T angle typically precedes it, followed by notable narrowing thereafter. Increased IAP also intensifies TBI-associated increases in spatial QRS-T angle and QTc interval.  相似文献   
27.
28.
Background: Immunomodulating enteral nutrition in the perioperative period may reduce postoperative complications in cancer patients. Little is known if this effect translates to the better survival. The aim of study was to assess the impact of postoperative immunomodulating enteral nutrition on postoperative complications and survival of gastric cancer patients. Methods: A group of 98 gastric cancer patients was randomly assigned for postoperative immunomodulating enteral nutrition n = 44 (Reconvan, Fresenius Kabi, Bad Homburg, Germany), or standard enteral nutrition n = 54 (Peptisorb, Nutricia, Schipol, The Netherlands). Postoperative complications, mortality, 6-mo and 1-yr survival were analyzed. Results: The overall postoperative morbidity did not differ between the groups. The rate of pulmonary complications (excluding pneumonia) was significantly lower in immunomodulation group (0% vs 9.3%, p = 0.044), as well as 60-day mortality (0% vs. 11.1%, p = 0.037). There was no difference in 6-mo and 1-yr survival between the groups. Conclusions: Postoperative immunomodulating enteral nutrition may reduce respiratory complications and postoperative mortality in comparison to standard enteral nutrition. Despite this effect, it did not improve 6-mo and 1-yr survival in immunomodulation group. Probably the beneficial effect of immunomodulating enteral nutrition is too weak to be significant in such a number of patients.  相似文献   
29.
30.
Visual imagery allows us to vividly imagine scenes in the absence of visual stimulation. The likeness of visual imagery to visual perception suggests that they might share neural mechanisms in the brain. Here, we directly investigated whether perception and visual imagery share cortical representations. Specifically, we used a combination of functional magnetic resonance imaging (fMRI) and multivariate pattern classification to assess whether imagery and perception encode the "category" of objects and their "location" in a similar fashion. Our results indicate that the fMRI response patterns for different categories of imagined objects can be used to predict the fMRI response patters for seen objects. Similarly, we found a shared representation of location in low-level and high-level ventral visual cortex. Thus, our results support the view that imagery and perception are based on similar neural representations.  相似文献   
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