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991.
In this study, a performance-enhanced charge trapping memory device with a Pt/Gd-doped HfO2/SiO2/Si structure has been investigated, where Gd-doped HfO2 acts as a charge trapping and blocking layer. The device demonstrates a large memory window of 5.4 V under a ±5 V sweeping voltage (360% of the device with pure HfO2), which is extremely attractive in low-power applications. In addition, the device also exhibits good retention characteristics with a 24.5% charge loss after the retention time of 1 × 105 seconds and robust endurance performance with a 1% degradation after 1 × 104 program/erase cycles. It is considered that the high density of defect states and the reduction in the defect energy levels induced by Gd-doping contribute to the performance improvement.

In this study, a performance-enhanced charge trapping memory device with a Pt/Gd-doped HfO2/SiO2/Si structure has been investigated, where Gd-doped HfO2 acts as a charge trapping and blocking layer.  相似文献   
992.
Micro/nanoscale tungsten probes are widely utilized in the fields of surface analysis, biological engineering, etc. amongst several others. This work performs comprehensive dynamic simulations on the influences of electric field distribution, surface tension and the bubbling situation on electrochemical etching behaviors, and then the tip dimension. Results show that the etching rate is reliant on the electric field distribution determined by the cathode dimension. The necking position lies in the meniscus rather than at the bottom of the meniscus. A bubble-free condition is mandatory to stabilize the distribution of OH and WO42− ions for a smooth tungsten probe surface. Such simulation-guidance enables the nanofabrication of probes with a high aspect ratio (10 : 1), ultra-sharp tip apex (40 nm) and ultra-smooth surface. These probes have been successfully developed for high-performance application with Scanning Tunneling Microscopy (STM). The acquired decent atomic resolution images of epitaxial bilayer graphene robustly verify the feasibility of the practical level application of these nanoscale probes. Therefore, these nanoscale probes would be of great benefit to the development of advanced analytical science and nano-to-atomic scale experimental science and technology.

Dynamic simulation is employed to reveal the mechanism of electrochemical nanofabrication of nanoscale probes for atomic resolution imaging in STM.  相似文献   
993.
Zeranol (α-zearalanol) has been used as a growth promoter in livestock since 1969 in some non-EU countries; the residues of zeranol and its five analogues in animal origin foods may endanger human health due to their strong estrogenic and anabolic activities. Therefore, it is urgent to establish simple, rapid, real-time, broad-spectrum and high-sensitivity detection methods for the residues of zeranol and its analogues. In this study, an ultrasensitive indirect-competition enzyme-linked immunosorbent assay (ic-ELISA) was established for the rapid multi-residue detection of zeranol and its five analogues in cattle origin samples, which was based on a broad-spectrum monoclonal antibody (mAb) that specifically bound to zeranol and its analogues with high sensitivity. The half maximal inhibitory concentration (IC50) values for zeranol, β-zearalanol, zearalanone, α-zearalenol, β-zearalenol, and zearalenone were 0.103, 0.080, 0.161, 0.177, 0.254, and 0.194 ng mL−1, respectively, the recovery rates of cattle origin samples spiked with zeranol ranged from 79.2–104.2%, and the coefficient of variation (CV) values were less than 11.4%. Excellent correlation (R2 = 0.9845) was obtained between the results of HPLC-MS/MS and ic-ELISA. In conclusion, the developed ic-ELISA could be employed as an ultrasensitive and broad-spectrum detection method for monitoring trace ZEN residues in cattle origin foods.

This paper presents a broad-spectrum and ultra-sensitive ic-ELISA method for the rapid detection of zeranol and its analogues in cattle origin samples.  相似文献   
994.
995.
996.

Purpose

To investigate the effect of the deleted in azoospermia (DAZ) copy cluster deletion on spermatogenesis in the South Chinese population.

Methods

In this study, the prevalence and characteristics of different DAZ copy cluster deletions and their association with spermatogenic failure were analyzed. A total of 186 infertile men with different spermatogenic impairments and 190 normozoospermic fertile men were studied. Three DAZ-specific single nucleotide variant loci and seven AZFc-specific sequence-tagged sites were examined using polymerase chain reaction (PCR)–restriction fragment length polymorphism and routine PCR.

Results

Gr/gr deletions were observed in a total of 9 of the 190 normozoospermic fertile men, and 11 gr/gr deletions were found in 186 infertile men. In addition, 3 b2/b3 deletions were identified in the infertile, but not in the fertile men. DAZ-SNV loci analysis revealed 4 DAZ copies that had 8 gr/gr-DAZ3/DAZ4 deletions and 1 gr/gr-DAZ1/DAZ2 deletion in the fertile men (8/190 vs. 1/190, p = 0.037). Analysis of DAZ deletion copies in infertile men revealed 10 gr/gr-DAZ1/DAZ2 deletions, 1 gr/gr-DAZ3/DAZ4 deletion (10/186 vs. 1/186, p = 0.011) and 3 b2/b3-DAZ1/DAZ2 deletions (13/186 vs. 1/186, p = 0.002).

Conclusions

Analysis of DAZ gene copies in AZFc microdeletions suggests that the contribution of the different deletions to male infertility varies. Removing DAZ1/DAZ2 seems to be associated with spermatogenic impairment, whereas removing DAZ3/DAZ4 seems to have little or no effect on fertility in the South Chinese population.  相似文献   
997.
The object of this study was to compare the outcomes of the vacuum assisted closure (VAC) therapy and conventional wound care with dressing change for treatment of complex wounds in patients with replantation of amputated upper and lower extremities. Data of 43 patients with replantation of amputated extremities from May 2004 to December 2011 were reviewed. There were 18 wounds of 18 patients with replantation, which were treated by dressing change and 26 wounds of 25 patients by VAC therapy. The outcomes were evaluated by the survival rate of replanted extremities, growth of granulation tissue, interval between wound treatment and secondary procedure and eventual secondary wound coverage methods. Vascular thromboses were found in 3 patients with wound treatment by dressing change and 5 by VAC. All replants of two groups of patients survived after salvage procedures. The wound score was 3.6 ± 0.7 in the conventional dressing change group and 5.8 ± 0.7 in the VAC group at the sixth day after treatment, respectively. The intervals between wound treatment and secondary wound coverage procedure were 12.0 ± 1.7 days in the dressing change group and 6.1 ± 0.7 days in the VAC group. Flaps were applied for wound coverage in 9 out of 18 (50.0%) wounds in the dressing change group and 5 out of 26 (19.2%) in the VAC group (P < 0.05), when the wounds of rest of patients were covered by the skin graft. The results showed that VAC could promote the growth of granulation tissue of wound, decrease the need of flap for wound coverage, and did not change the survival of replantation. © 2013 Wiley Periodicals, Inc. Microsurgery 33:620–624, 2013.  相似文献   
998.
The deep inferior epigastric artery perforator (DIEP) flap has been a valuable tool in breast reconstruction, but seldom in extremity reconstruction. The aim of this report is to present our experience on the use of the DIEP flap for reconstruction of soft‐tissue defects in the extremities of pediatric patients. From January 2007 to February 2011, 22 consecutive free DIEP flap transfers were performed for reconstruction of complex soft‐tissue defects in the extremities of children with a mean age of 5.7 years old (ranging 2–10 years old). The flap design included transverse, oblique, and irregular DIEP flaps, containing one to three perforators in the flap. The flap size ranged from 7 × 4 cm to 18 × 17 cm. Primary donor‐site closure was accomplished in all of patients. The postoperative course was uneventfully in most of cases. The venous congestion was observed in two cases. One case of venous congestion was caused by flap inset with tension. The other case with venous thrombosis ended with partial loss of the flap after salvage procedure. There was one total flap loss due to the arterial thrombosis. The flap survival rate was 95.5%. The mean follow‐up was 12 months (ranging 6–36 months). All reconstructed extremities had satisfactory aesthetic and functional outcomes except two cases undergoing the secondary debulking procedures. The donor sites healed well in all cases without complications. Our experience showed that the free DIEP flap could be an alternative for reconstruction of soft‐tissue defects in the extremities of children. © 2013 Wiley Periodicals, Inc. Microsurgery 33:612–619, 2013.  相似文献   
999.
Although more and more clinical studies indicated that ImmuKnow assay could efficiently assess the immune status of recipients, it still has the challenge to predict the occurrence of clinical adverse events. This study aimed to establish a quantitative assessment model, which could more efficiently predict immune function of T lymphocytes after liver transplantation based on three indexes: CD4+ T lymphocyte count (C), CD4+/CD8+ ratio (R), and ImmuKnow adenosine triphosphate (ATP) value (A). We selected 194 recipients and measured the A, C, and R index every week, then obtained the Fisher linear discriminant functions by SPSS 16.0. Next, we divided the recipients into three groups: infection, stable, and rejection groups according to clinical status. After calculating, the discriminant function, 0.012A + 0.019C + 1.322R (simplified into T = 2A + 3C + 200R), was selected to represent the T‐cell‐mediated immune function. Based on the model, the optimal cutoff T values for infection and rejection were 1415 (sensitivity = 80%, specificity = 79.9%,AUC = 92.3%) and 1939.5 (sensitivity = 93.9%, specificity = 77.6%, AUC = 88.6%), relatively (p < 0.001). In conclusion, this model may be a more feasible way to evaluate the cellular immune function status in liver transplantation recipients.  相似文献   
1000.

Objectives

This systematic review determined whether the duloxetine can get more benefits versus placebo in managing women with stress urinary incontinence (SUI) all over the world.

Methods

We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing duloxetine with placebo in these patients. The eligible RCTs were identified from the following electronic databases: Cochrane CENTRAL, Medline and EMBASE. We treated the incontinence episode frequency (IEF) as the main outcome, and the secondary outcomes were cured, average voiding interval, incontinence quality of life (I-QOL), treatment-emergent adverse events (TEAEs) and discontinuation.

Results

The review contained ten trials including 5,738 women who were randomized to take duloxetine or placebo. All arms in individual trials were comparable for various baseline characteristics. Individual studies showed a significantly greater decrease in IEF than placebo group. The total IEF responders (defined as a woman who had at least a 50 % decrease in IEF with treatment) within the duloxetine-treated women were more than the placebo-treated women (52.5 vs. 33.7 %; RR = 1.56; 95 %CI, 1.46–1.66; p < 0.00001). TEAEs were commonly experienced by both two groups (62.7 vs. 45.3 %) though they were not critical.

Authors’ conclusions

Our meta-analysis showed that significant efficacy can be found in women treated with a certain dose of duloxetine. The adverse events like nausea, constipation, dry mouth, fatigue etc. are common.  相似文献   
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