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1.
《Survey of ophthalmology》2023,68(5):920-928
There remains limited agreement regarding the efficacy and safety of different antivascular endothelial growth factor (anti-VEGF) agents for the management of polypoidal choroidal vasculopathy (PCV). Our meta-analysis compares different anti-VEGF agents for PCV treatment. Ovid MEDLINE, EMBASE, and Cochrane Library were systematically searched from January 2000 to July 2022. We included articles comparing the efficacy and safety of different anti-VEGF agents, specifically bevacizumab (BEV), ranibizumab (RAN), aflibercept AFL), and brolucizumab (BRO), for patients with PCV. 10,440 studies were identified, 122 underwent full-text review, and seven were included. One study was a randomized trial, and six were observational studies. Ranibizumab and aflibercept were associated with a similar best-corrected visual acuity (BCVA) at the last visit in three observational studies (P = 0.10), similar retinal thickness at the last visit in two observational studies (P = 0.85). One observational study comparing BEV versus RAN found comparable outcomes for final BCVA, retinal thickness, and polyp regression. One randomized trial on BRO versus AFL found comparable outcomes for improvement in BCVA, while anatomical outcomes favored BRO. The available evidence suggests that final BCVA is comparable across different anti-VEGF agents, however, further investigation is warranted due to paucity of evidence.  相似文献   
2.
余川  万光明 《国际眼科杂志》2022,22(9):1473-1477

眼静脉空气栓塞(OVAE)是玻璃体切割手术中一种罕见的致命并发症。因手术部位靠近心脏且位于心脏上方,OVAE可能是所有手术中引起静脉空气栓塞(VAE)最严重的。随着玻璃体切割手术的发展,免缝合状态的灌注套管可出现向外滑动,使得灌注气体进入脉络膜上腔,导致涡静脉撕裂。玻璃体腔气体灌注时,外伤及脉络膜黑色素瘤手术导致的脉络膜血管伤口暴露于气体中,这使得加压气体可能通过撕裂的涡静脉或异常的脉络膜静脉开口进入循环系统导致OVAE。目前OVAE的定义、发病机制、临床表现及防治措施在不断完善,但多数玻璃体视网膜外科医生和麻醉医师仍不了解该医源性并发症。提高对OVAE的认识将有助于早期发现该并发症,进而做出及时处理,同时制定有效的预防策略。通过临床和实验室研究相结合,可不断优化OVAE防治原则。充分认识OVAE的发病机理和临床特点,关注 OVAE继发性病变的特征以及重视多学科间的合作有助于OVAE应急处理和预防措施的建立和完善。  相似文献   

3.
目的:设计一种新的双元件可调节人工晶状体,并对其成像质量进行评估。方法:通过光学设计软 件Zemax,建立新设计的双元件可调节人工晶状体和人眼模型,模拟仿真其在不同视距下(L=6 m、 L=70 cm、L=40 cm以及L=25 cm)的成像结果,得到空间频率为100 cycles/mm时的调制传递函数 (MTF)值。与Simonov等研究结果进行对比分析,同时分析仿真结果是否满足人工晶状体植入光学 特性和测试标准。结果:通过光学设计软件模拟仿真新设计的双元件可调节人工晶状体眼模型,其 结果显示无论α=0°还是α=5°,瞳孔大小为3 mm时,单色光(λ=0.546 μm)空间频率100 cycles/mm 对应的MTF值均大于0.43,满足人工晶状体植入光学特性和测试标准。在α=0°时,仿真结果相较 于Simonov等研究结果有较大提升;在α=5°时,无明显提升。结论:本研究设计的双元件可调节人 工晶状体仿真结果满足人工晶状体植入光学特性和测试标准要求,相较于Simonov的研究结果,其 整体性能有所提升。  相似文献   
4.
Background: To compare the differential diagnostic value of iterative decomposition of water and fat with the echo asymmetrical and least-squares estimation quantitation sequence (IDEAL-IQ) with that of intravoxel incoherent motion diffusion-weighted imaging (IVIM DWI) in differentiating between alpha fetoprotein (AFP)-negative hepatocellular carcinoma (HCC) and focal nodular hyperplasia (FNH). Materials and Methods: A total of 28 AFP-negative HCC cases and 15 FNH cases were scanned using the IDEAL-IQ and IVIM-DWI magnetic resonance imaging (MRI) protocols. Two radiologists independently assessed the fat fraction (FF) and the iron level surrogate (R2*) derived from the IDEAL-IQ images and the apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) derived from the IVIM-DWI images. The intraclass correlation coefficients (ICC) were estimated to evaluate the agreement repeatability between the two readers. The area under the curve (AUC) of a receiver operating characteristics curve was used to compare the diagnostic efficiency of the parameters extracted from the two techniques. Results: The lesions in the HCC group had significantly higher FF than the FNH group (8.284 ± 5.756 vs. 2.559 ± 1.247, P < 0.05). ADC and D values were lower in the HCC lesions when compared with the FNH lesions (1.310 ± 0.253 and 0.909 ± 0.192, respectively, vs. 1.624 ± 0.304 and 1.230 ± 0.314; ×10−3 mm2 /s). The FF parameter had the highest AUC (0.923) followed by D (0.864) and ADC (0.854). Conclusions: FF derived from IDEAL-IQ, and ADC and D derived from IVIM-DWI were able to differentiate AFP-negative HCC from FNH. IDEAL-IQ showed better performance for the differentiation of FNH from HCC than the IVIM-DWI-derived parameters.  相似文献   
5.
目的 探讨不同类型脉络膜新生血管(CNV)患者对抗血管内皮生长因子(VEGF)药物治疗应答的差异性。方法 本研究为回顾性研究。选取2016年10月至2021年9月在我院门诊确诊并接受康柏西普治疗的CNV患者50例68眼。依据CNV类型将患者分成3组,I型CNV组患者16例20眼,II型CNV组患者25例35眼,混合型CNV组患者9例13眼。采用德国海德堡公司共焦激光同步血管造影系统的增强扫描技术扫描获得患者黄斑中心凹脉络膜厚度(SFCT),记录患者治疗前后相应时间点的最佳矫正视力(BCVA) (logMAR),记录治疗后不同时间患者注药次数、需再治疗眼数和患者CNV复发率等。采用SPSS 23.0统计学软件对所得数据进行统计分析。结果 II型CNV组患者治疗后1周、1个月及2个月的BCVA较基线提高量高于I型CNV组和混合型CNV组,差异均有统计学意义(均为P<0.05);混合型CNV组患者治疗后6个月、8个月及12个月BCVA较基线提高量低于I型CNV组和II型CNV组,差异均有统计学意义(均为P<0.05)。三组患者治疗后SFCT较基线均有所提高,差异均有统计学意义(均为P<0.05)。混合型CNV组患者治疗后8个月、12个月的SFCT较基线恢复厚度低于I型CNV组和II型CNV组,差异均有统计学意义(均为P<0.05)。随访0~24个月,三组患者总注药次数差异有统计学意义(P<0.05),SNK-q检验结果显示:I型CNV组及II型CNV组患者注药次数少于混合型CNV组(均为P<0.05)。三组患者需再治疗眼率差异有统计学意义(P<0.05);混合型CNV组患者需再治疗眼率高于I型CNV组及II型CNV组[需再治疗眼数率差95%CI分别为(0.051,0.133)和(0.041,0.142)]。三组患者注药后复发率差异无统计学意义(P>0.05)。结论 II型CNV在抗VEGF治疗早期应答更好,而II型CNV及I型CNV在治疗后期应答反应趋于相近;混合型CNV在治疗后期应答不良。  相似文献   
6.
7.
AIM: To compare choroidal neovascularization (CNV) lesion measurements obtained by in vivo imaging modalities, with whole mount histological preparations stained with isolectin GS-IB4, using a murine laser-induced CNV model. METHODS: B6N.Cg-Tg(Csf1r-EGFP)1Hume/J heterozygous adult mice were subjected to laser-induced CNV and were monitored by fluorescein angiography (FA), multicolor (MC) fundus imaging and optical coherence tomography angiography (OCTA) at day 14 after CNV induction. Choroidal-retinal pigment epithelium (RPE) whole mounts were prepared at the end of the experiment and were stained with isolectin GS-IB4. CNV areas were measured in all different imaging modalities at day 14 after CNV from three independent raters and were compared to choroidal-RPE whole mounts. Intraclass correlation coefficient (ICC) type 2 (2-way random model) and its 95% confidence intervals (CI) were calculated to measure the correlation between different raters'' measurements. Spearman''s rank correlation coefficient (Spearman''s r) was calculated for the comparison between FA, MC and OCTA data and histology data. RESULTS: FA (early and late) and MC correlates well with the CNV measurements ex vivo with FA having slightly better correlation than MC (FA early Spearman''s r=0.7642, FA late Spearman''s r=0.7097, and MC Spearman''s r=0.7418), while the interobserver reliability was good for both techniques (FA early ICC=0.976, FA late ICC=0.964, and MC ICC=0.846). In contrast, OCTA showed a poor correlation with ex vivo measurements (Spearman''s r=0.05716) and high variability between different raters (ICC=0.603). CONCLUSION: This study suggests that FA and MC imaging could be used for the evaluation of CNV areas in vivo while caution must be taken and comparison studies should be performed when OCTA is employed as a CNV monitoring tool in small rodents.  相似文献   
8.
9.
Abstract

Purpose: In our study, we aimed to investigate the ganglion cell-inner plexiform layer thickness (GCIPL), retinal nerve fibre layer thickness (RNFL), mean macular volume (MMV), central macular thickness (CMT), mean macular thickness (MMT), and choroidal thickness (CT) values with optical coherence tomography (OCT) in patients who are diagnosed with alcohol use disorder (AUD).

Materials and methods: The study included 43 patients who were diagnosed with AUD, and 43 healthy controls. Detailed biomicroscopic examinations of all the participants, visual acuity, intraocular pressure, anterior and posterior segment examinations, and then, OCT measurements were carried out.

Results: Although the measured values for RNFL in the superior and temporal quadrant are within normal limits, they were slightly higher compared to those in the control group (p values 0.127 and 0.191 for superior quadrant and temporal quadrant, respectively). The CT measurements in all quadrants were higher than the control group; however, these measurements were not statistically significant (p?>?0.05). When the relation between clinical features and OCT findings of the patients were examined, it was determined that the ages of the patients were statistically significantly and inversely correlated with the temporal CT and also the nasal and temporal quadrants of RNFL.

Conclusions: Our study is the first study that examines the retinal GCIPL and CT with OCT in patients who are diagnosed with AUD. In our results, it was determined that there were no statistically significant differences between the participants in terms of OCT parameters. Further studies with larger sampling groups evaluating neurotransmission findings may provide wider results.  相似文献   
10.
徐晓玮  黎彪  邵毅 《国际眼科杂志》2019,19(9):1488-1491

随着基因工程技术的不断成熟,现有多种针对脉络膜新生血管(CNV)发展的关键因素和过程的基因工程小鼠模型,以适应针对CNV过程不同研究要点的需求。例如针对CNV过程中关键因素血管内皮生长因子(VEGF)的VEGF164 RPE65转基因、Tet/VMD2/VEGF等; ApoE过表达小鼠是年龄相关性黄斑病变中自发性CNV形成机制的重要模型; 与视网膜色素上皮(RPE)变化相关的Ccl2/Cx3cr1缺陷小鼠; 脉络膜新生血管与视网膜新生血管吻合过程可见于SOD1-/ -老化、Vldlr -/-定向突变等; 继发于脉络膜新生血管的视网膜新生血管可见于Cp-/-Heph-/Y敲除小鼠等。这些基因工程小鼠的主要优点为诱导快,发生时间短; 与CNV病理生理学关联强,可比较CNV各种生物学成分,便于对其发生机制的研究; 与人类CNV关联密切,为人类CNV治疗评估提供研究手段等。但其也有不足,如诱导率低、发生CNV眼的百分率低、面积小; 常发视网膜增生性瘤性病变,对CNV研究造成了一定干扰。研究者可根据自己的需求选择适合的模型并适当修改相应实验参数。  相似文献   

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