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91.
Plant miRNAs, the critical regulator of gene expression, involve many development processes in vivo. However, the roles of miRNAs in plant cell proliferation and redifferntiation in vitro remain unknown. To determine better the molecular mechanism of these processes, we have recently reported that a set of miRNAs with different expression patterns between cells of totipotent and non-totipotent Arabidopsis calli. Some of these were specifically up- or downregulated during callus formation or shoot regeneration, and other development. Among them, miR160, and one of its target genes, ARF10, regulated Arabidopsis in vitro shoot regeneration via WUS, CLV3 and CUC1/2. The miR160-overexpressing, 35S transgenic lines, exhibited reduced shoot regeneration efficiency. The mARF10, a miR160-resistant form of ARF10, showed a high level of shoot regeneration ability. In the transgenic, expression of the above shoot meristem-specific genes was elevated, which is consistent with the improved shoot regeneration. In contrast, the ARF10 deficient knockout mutant produced fewer regenerated shoot. However, overexpressors of ARF10 were only marginally more efficient than the wild type with the respect to shoot regeneration. Our observation strongly supports that proper shoot regeneration from in vitro cultured cells requires the miR160-directed negative influence of ARF10. The enhanced expression of ARF10 is likely to have contributed to the improved regeneration ability.  相似文献   
92.
The epidermal growth factor receptor (EGFR) signaling pathway regulates cell proliferation, differentiation, and survival, and is frequently dysregulated in esophageal and gastric cancers. Few studies have comprehensively examined the association between germline genetic variants in the EGFR pathway and risk of esophageal and gastric cancers. Based on a genome-wide association study in a Han Chinese population, we examined 3443 SNPs in 127 genes in the EGFR pathway for 1942 esophageal squamous cell carcinomas (ESCCs), 1758 gastric cancers (GCs), and 2111 controls. SNP-level analyses were conducted using logistic regression models. We applied the resampling-based adaptive rank truncated product approach to determine the gene- and pathway-level associations. The EGFR pathway was significantly associated with GC risk (P = 2.16×10−3). Gene-level analyses found 10 genes to be associated with GC, including FYN, MAPK8, MAP2K4, GNAI3, MAP2K1, TLN1, PRLR, PLCG2, RPS6KB2, and PIK3R3 (P<0.05). For ESCC, we did not observe a significant pathway-level association (P = 0.72), but gene-level analyses suggested associations between GNAI3, CHRNE, PAK4, WASL, and ITCH, and ESCC (P<0.05). Our data suggest an association between specific genes in the EGFR signaling pathway and risk of GC and ESCC. Further studies are warranted to validate these associations and to investigate underlying mechanisms.  相似文献   
93.
Monitoring intraocular pressure (IOP) is essential for pediatric cataract treatment but always difficult due to lack of cooperation in young children. We present the baseline characteristics and the first-year results of a long-term prospective cohort study, which are aimed to determine the relationship of the incidence of ocular hypertension (OH) in children after cataract surgery during the first-year period and the risk of developing late-onset glaucoma. Children were included with the following criteria: they were≤10 years old and scheduled to undergo cataract surgery with/without intraocular lens implantation; they were compliant with our follow-up protocol, which included monitoring IOP using a Tono-Pen under sedation or anesthesia. Incidence of OH, peak OH value, OH onset time and OH duration within a 12-month period following surgery were measured. In brief, 206 patients (379 eyes) were included and OH developed in 66 of 379 (17.4%) eyes. The mean follow-up period was 14.0±3.2 months (median, 12 months; range, 10–16 months). Moreover, 33 of 196 (16.8%) aphakic eyes and 33 of 183 (18.0%) IOL eyes were diagnosed with OH. The peak OH onset times were at 1-week (34/66, 51.5%) and 1-month (14/66, 21.2%) appointments postsurgery. The peak IOP value in the OH eyes was 29.9±7.5 mmHg (median, 29 mmHg; range, 21–48 mmHg). The duration of OH was 30.9±31.2 days (median, 30 days; range, 3–150 days). OH recurred in 13 eyes with a history of OH diagnosed within 1 month postsurgery (13/54, 24.1%), which needed temporary or long term use of antiglaucoma medications. In conclusion, the incidence of OH in children after cataract surgery was 17.4% during the first-year period. Children who have suffered elevated IOP in the first year after cataract surgery should be followed closely to determine if there is an increased risk of developing late-onset glaucoma.  相似文献   
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Background

To develop a method for systematic classification of gallbladder stones, analyze the clinical characteristics of each type of stone and provide a theoretical basis for the study of the formation mechanism of different types of gallbladder stones.

Methodology

A total of 807 consecutive patients with gallbladder stones were enrolled and their gallstones were studied. The material composition of gallbladder stones was analyzed using Fourier Transform Infrared spectroscopy and the distribution and microstructure of material components was observed with Scanning Electron Microscopy. The composition and distribution of elements were analyzed by an X-ray energy spectrometer. Gallbladder stones were classified accordingly, and then, gender, age, medical history and BMI of patients with each type of stone were analyzed.

Principal Findings

Gallbladder stones were classified into 8 types and more than ten subtypes, including cholesterol stones (297), pigment stones (217), calcium carbonate stones (139), phosphate stones (12), calcium stearate stones (9), protein stones (3), cystine stones (1) and mixed stones (129). Mixed stones were those stones with two or more than two kinds of material components and the content of each component was similar. A total of 11 subtypes of mixed stones were found in this study. Patients with cholesterol stones were mainly female between the ages of 30 and 50, with higher BMI and shorter medical history than patients with pigment stones (P<0.05), however, patients with pigment, calcium carbonate, phosphate stones were mainly male between the ages of 40 and 60.

Conclusion

The systematic classification of gallbladder stones indicates that different types of stones have different characteristics in terms of the microstructure, elemental composition and distribution, providing an important basis for the mechanistic study of gallbladder stones.  相似文献   
96.
Wan  Yingling  Zhang  Min  Hong  Aiying  Lan  Xinyu  Yang  Huiyan  Liu  Yan 《Plant molecular biology》2020,102(3):239-252
Plant Molecular Biology - Lack of structural components results in inflorescence stem bending. Differentially expressed genes involved in lignin and hemicellulose biosynthesis are vital; genes...  相似文献   
97.
98.
Ju  Wen  Sun  Tiantian  Lu  Wenyi  Smith  Alhaji Osman  Bao  Yurong  Adzraku  Seyram Yao  Qi  Kunming  Xu  Kailin  Qiao  Jianlin  Zeng  Lingyu 《Molecular biology reports》2020,47(4):2735-2748
Molecular Biology Reports - Murine bone marrow-derived macrophages (M0) and M1- and M2-polarized macrophages are being widely used as a laboratory model for polarized macrophages related molecular...  相似文献   
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100.
Recently, the use of hybrid double network (DN) hydrogels has become prominent due to their enhanced mechanical properties, which has opened the door for new applications of these soft materials. Only a few of these gels have demonstrated both injectable and moldable capabilities. In this work, we report the mechanical properties, gauge factor (GF) values and demonstrate both the injectability and moldability of a gelatin/polyacrylamide DN hydrogel. We optimized several parameters, such as, gelatin to polyacrylamide ratio, reactant concentrations and metal ion concentration, to produce a gelatin/polyacrylamide hydrogel with superior mechanical properties. The highest water content gel was capable of withstanding strains of 5000% before failure. These gels were facilely injected into molds where they effectively changed shape and maintained similar properties prior to remolding. When 20 mM calcium was doped into a similar gel, a tensile strength of 1.71 MPa was achieved. Aside from improving the mechanical properties of the gels, both Ca2+ and Mg2+ also improved their conductivity, so they were tested for use as strain sensors. The sensitivity of the hydrogel strain sensors were measured using the GF. For the 20 mM Ca2+ hydrogel, these GF values ranged from 1.63 to 6.85 for strains of 100% to 2100% respectively. Additionally, the sensors showed good stability over continuous cyclic stretching, demonstrating their long term reliability for strain sensing.  相似文献   
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