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The purpose of this study was to test the feasibility of MR-guided percutaneous ethanol ablation of liver tissue on a .2-T open MR scanner. Needles were placed by MR guidance first into an ex vivo sheep liver and then into livers of three anesthetized pigs, and injection of 10 ml of 96% alcohol was performed. T1 fast low-angle shot (FLASH), T2 turbo spin echo (TSE), and T1 spin echo (SE) images were obtained after incremental volumes of injection. In one pig, simultaneous injection of saline into normal liver was also performed with subsequent pathological correlation. Ethanol-infiltrated liver was hypointense to liver on all sequences, whereas saline caused no tissue signal changes on T1 SE and either isointense or hyperintense changes on T2 TSE images. Pathological examination confirmed ethanol-induced acute liver changes as compared with the control. MR guidance of needle placement and monitoring of ethanol effects on liver tissue is feasible. This may have implications for potential MR-guided hepatic tumor ablation.  相似文献   
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PURPOSE: To determine the independent relationship between leukoreduced platelet transfusions and adverse events in cardiac surgery. METHODS: In this observational study, detailed baseline and perioperative data were prospectively collected on consecutive patients who underwent cardiac surgery at a single institution from 1999 to 2004. The independent associations of platelet transfusion with clinical outcomes (low output syndrome, myocardial infarction, stroke, renal failure, sepsis, and death) were determined by multivariable logistic regression analysis and propensity score case-control analysis. RESULTS: Of the 11,459 patients analyzed, 2,174 (19%) received (leukoreduced) platelets - 1,408 received 5 U, 471 received 10 U, 140 received 15 U, and 155 received 20 or more units. Although all measured adverse event rates were higher in those who received platelets, in neither the logistic regression analyses nor the propensity score analyses was there any association between platelet transfusion and any of the adverse events. CONCLUSIONS: Transfusion of leukoreduced platelets in cardiac surgery is not associated with adverse clinical outcomes when adjustments are made for important confounders.  相似文献   
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BACKGROUND: The optimal time frame to improve the quality and cosmetic appearance of scars by laser therapy has not been clearly elucidated by prior controlled clinical trials. OBJECTIVE: To determine the efficacy of the 585-nm pulsed dye laser (PDL) in the treatment of surgical scars starting on the day of suture removal. METHODS: Eleven patients (skin types I-IV) with 12 postoperative linear scars that were greater than 2 cm were treated three times on monthly intervals with the 585-nm PDL (450 micro s, 10-mm spot size, 3.5 J/cm2 with 10% overlap) on one scar half, whereas the other half received no treatment. Scars were later evaluated by a blinded examiner using the Vancouver Scar Scale (VSS) for pigmentation, vascularity, pliability, and height. Scars were then blindly examined for cosmetic appearance using a visual analog scale. RESULTS: One month after the last treatment, final scar analysis by the blinded examiner revealed a significant difference between treated and untreated sites, with the treated halves scoring better in all scar parameters in the VSS and in cosmetic appearance. The treated halves demonstrated an overall average improvement in the VSS between the first treatment score and the final score of 54% versus 10% in the controls (P=0.0002). The cosmetic appearance score (0=worst; 10=best) at final assessment was significantly better for the treated scars, scoring 7.3 versus the averaged control score of 5.2 (P=0.016). CONCLUSION: The 585-nm PDL is effective and safe in improving the quality and cosmetic appearance of surgical scars in skin types I-IV starting on the day of suture removal.  相似文献   
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The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy  相似文献   
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The use of laser to treat cutaneous lesions began with Dr. Leon Goldman and his coworkers in 1963. Ten years later, these authors described promising effects on angiomas using the continuous-wave neodymium:yttrium–aluminum–garnet laser. In 1983, Anderson et al. proposed the photothermolysis theory. The selective destruction of vascular lesions is based on this principle, and it is still a guide for treatment of vascular lesions. Over the past 25 years, laser treatment of cutaneous vascular lesions has progressed significantly. Vascular lasers such as argon, tunable dye, krypton, and copper vapor were used in the past and were associated not only with risk of scarring but also hyper- and hypopigmentation. Since then, new devices were developed in order to minimize these side effects. This article presents an overview and update of the current available treatment of cutaneous vascular lesions and covers future directions for vascular laser technology.  相似文献   
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Demineralized bone matrix (DBM) is a complex mixture of osteoinductive bone morphogenetic proteins (BMPs), as well as BMP-binding proteins that regulate BMP bioactivity and localization. Our aim was to use modern proteomic methods to identify additional BMP-binding proteins in DBM, with initial emphasis on the most abundant. Relatively large, water-soluble noncollagenous proteins (NCPs) were preferentially extracted from DBM with alkalinized urea. The insoluble residue, which contained the BMP activity, was extracted with GuHCl/CaCl2, dialyzed versus citrate, defatted, resuspended in GuHCl, dialyzed sequentially against Triton X-100 and water, pelleted, and lyophilized. The proteins in this pellet were fractionated by hydroxyapatite affinity chromatography. Proteins that copurified with BMP bioactivity were separated by SDS-PAGE. Distinct bands were excised, and the proteins in them were reduced and alkylated, digested with trypsin, eluted, and subjected to MALDI/ToF MS (matrix-assisted laser-desorption ionization time-of-flight mass spectrometry). Computer-assisted peptide fingerprint analysis of the MS profiles was used to identify C-terminal lysine-6-oxidase; dermatopontin (DPT); histones H2A2, H2A3, and H2B; and trace amounts of γ-actin. DPT is a 22-kDa, tyrosine-rich acidic matrix protein not previously recognized to be among the most abundant small proteins to copurify with BMP bioactivity in DBM. We tested the effects of DPT on BMP-2 stimulation of alkaline phosphatase (ALP) activity in C2C12 cells. BMP-2 stimulated ALP activity in C2C12 cells by 6.2-fold above basal levels. DPT alone had no effect on ALP activity in C2C12 cells. When added with BMP-2, DPT blocked 40% of the stimulatory effect of BMP-2 on ALP activity in C2C12 cells. DPT is an abundant protein in DBM, and it can inhibit the stimulatory effects of BMP-2 on ALP activity in C2C12 cells.  相似文献   
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