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991.
Goot Heah Khor Gabriele Ruth Anisah Froemming Rosnah Binti Zain Mannil Thomas Abraham Effat Omar Su Keng Tan Aik Choon Tan Vui King Vincent-Chong Kwai Lin Thong 《International journal of medical sciences》2013,10(12):1727-1739
Background: Hypermethylation in promoter regions of genes might lead to altered gene functions and result in malignant cellular transformation. Thus, biomarker identification for hypermethylated genes would be very useful for early diagnosis, prognosis, and therapeutic treatment of oral squamous cell carcinoma (OSCC). The objectives of this study were to screen and validate differentially hypermethylated genes in OSCC and correlate the hypermethylation-induced genes with demographic, clinocopathological characteristics and survival rate of OSCC.Methods: DNA methylation profiling was utilized to screen the differentially hypermethylated genes in OSCC. Three selected differentially-hypermethylated genes of p16, DDAH2 and DUSP1 were further validated for methylation status and protein expression. The correlation between demographic, clinicopathological characteristics, and survival rate of OSCC patients with hypermethylation of p16, DDAH2 and DUSP1 genes were analysed in the study.Results: Methylation profiling demonstrated 33 promoter hypermethylated genes in OSCC. The differentially-hypermethylated genes of p16, DDAH2 and DUSP1 revealed positivity of 78%, 80% and 88% in methylation-specific polymerase chain reaction and 24% and 22% of immunoreactivity in DDAH2 and DUSP1 genes, respectively. Promoter hypermethylation of p16 gene was found significantly associated with tumour site of buccal, gum, tongue and lip (P=0.001). In addition, DDAH2 methylation level was correlated significantly with patients'' age (P=0.050). In this study, overall five-year survival rate was 38.1% for OSCC patients and was influenced by sex difference.Conclusions: The study has identified 33 promoter hypermethylated genes that were significantly silenced in OSCC, which might be involved in an important mechanism in oral carcinogenesis. Our approaches revealed signature candidates of differentially hypermethylated genes of DDAH2 and DUSP1 which can be further developed as potential biomarkers for OSCC as diagnostic, prognostic and therapeutic targets in the future. 相似文献
992.
The selection and preparation of an electrode material is the core of capacitive deionization. In order to obtain a material with a good deionization properties, we have designed an environmentally-friendly and simple way of preparing biochar. In this work, biochar was prepared by a thermal-deposition method and after chemical modification it was characterized with a scanning electron microscope (SEM), Fourier transform infrared spectrophotometer (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The specific surface area of biochar modified by KOH is as high as 833.76 m2 g−1, but the specific surface area of the unmodified electrode material is only 126.43 m2 g−1. The electrochemical analysis (CV and EIS) of the biochar indicates that HC-800 has a lower charge transfer resistance and a higher specific capacitance, where the specific capacity of HC-800 reaches 120 F g−1. A CDI property analysis of HC-800 shows a better electrosorption capacity of 11.52 mg g−1 and better regeneration and cycling stability than CS-800. The desalination amount remains 87.23% after several cycles.Schematic illustration of the fabrication of chitin derived biochar and KOH-activated chitin derived biochar electrodes for capacitive deionization. 相似文献
993.
Tan Huu Nguyen Osman Oguz Ahsen Kaicheng Liang Jason Zhang Hiroshi Mashimo James G. Fujimoto 《Biomedical optics express》2021,12(1):226
Catheter/endoscope-based optical coherence tomography (OCT) is a powerful modality that visualizes structural information in luminal organs. Increases in OCT speed have reduced motion artifacts by enabling acquisition faster than or comparable to the time scales of physiological motion. However motion distortion remains a challenge because catheter/endoscope OCT imaging involves both circumferential and longitudinal scanning of tissue. This paper presents a novel image processing method to estimate and correct motion distortion in both the circumferential and longitudinal directions using a single en face image from a volumetric data set. The circumferential motion distortion is estimated and corrected using the en face image. Then longitudinal motion distortion is estimated and corrected using diversity of image features along the catheter pullback direction. Finally, the OCT volume is resampled and motion corrected. Results are presented on synthetic images and clinical OCT images of the human esophagus. 相似文献
994.
Cynthia Tsien Huey Tan Sowmya Sharma Naaventhan Palaniyappan Pramudi Wijayasiri Kristel Leung Jatinder Hayre Elizabeth Mowlem Rachel Kang Peter J Eddowes Emilie Wilkes Suresh V Venkatachalapathy Indra N Guha Lilia Antonova Angela C Cheung William JH Griffiths Andrew J Butler Stephen D Ryder Martin W James Guruprasad P Aithal Aloysious D Aravinthan 《Clinical medicine (London, England)》2021,21(1):e32
995.
996.
A biodegradable linear bio-based polyester of poly(hexylene succinate) was effectively prepared in non-metal sulfonic acid-functionalized Brønsted acidic ionic liquids (SFBAILs) as both the catalyst and the polymerization medium, and the processes of polycondensation and post-polycondensation in SFBAILs were also investigated. In addition, the side reactions which were detrimental to the growth of Mw of poly(hexylene succinate) were evaluated and the synthesis mechanism of poly(hexylene succinate) catalyzed by SFBAILs was discussed with the help of DFT calculations. The result shows that both the imidazole ring and the sulfonic group on cations of SFBAILs play an important role in the catalytic process.Biobased poly(hexylene succinate) synthesized in sulfonic acid-functionalized Brönsted acidic ionic liquids was monitored by 1H NMR spectra and DFT calculations. 相似文献
997.
目的研究肺硬化性血管瘤(PSH)的CT征象与临床病理特征,提高对PSH的认识水平。方法收集2007—2013年我院经手术病理证实的PSH 20例。分别回顾性总结分析其CT影像资料及PSH病理资料。CT的评价征象包括病变形态、密度、边缘、分布位置及增强前后CT值的差值。PSH病理资料包括组织形态结构与细胞学形态。结果 20例PSH的CT均表现为单发、边缘清楚的圆形或是类圆形肿块,12例行增强扫描者均表现均匀显著强化。20例PSH均未发现肺门及纵隔淋巴结肿大,肺内亦未见转移灶。显微镜下,PSH主要由实体型、乳头型、硬化型和血管瘤型4种组织学形态,单个瘤体包括至少2种或2种以上组织形式。结论了解PSH的CT与病理特征,有利于提高对PSH的认识与诊断正确率。 相似文献
998.
The effect of a forced‐air warming blanket on patients' end‐tidal and transcutaneous carbon dioxide partial pressures during eye surgery under local anaesthesia: a single‐blind,randomised controlled trial 下载免费PDF全文
Surgical drapes used during eye surgery are impermeable to air and hence risk trapping air underneath them. We investigated the effect of a forced‐air warming blanket on carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia without sedation. Forty patients of ASA physical status 1 and 2 were randomly assigned to either the forced‐air warmer (n = 20) or a control heated overblanket (n = 20). All patients were given 1 l.min?1 oxygen. We measured transcutaneous and end‐tidal carbon dioxide partial pressures, heart rate, arterial pressure, respiratory rate, temperature and oxygen saturation before and after draping, then every 5 min thereafter for 30 min. The mean (SD) transcutaneous carbon dioxide partial pressure in the forced‐air warming group stayed constant after draping at 5.7 (0.2) kPa but rose to a maximum of 6.4 (0.4) kPa in the heated overblanket group (p = 0.0001 for the difference at time points 15 min and later). We conclude that forced‐air warming reduces carbon dioxide accumulation under the drapes in patients undergoing eye surgery under local anaesthesia. 相似文献
999.
1000.