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951.
Quantitative Relationships Between the Cytotoxicity of Flavonoids on the Human Breast Cancer Stem‐Like Cells MCF7‐SC and Their Structural Properties
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Hyeryoung Jung Soon Young Shin Yearam Jung Thao Anh Tran Hye Ok Lee Kang‐Yeoun Jung Dongsoo Koh Somi Kim Cho Yoongho Lim 《Chemical biology & drug design》2015,86(4):496-508
As some breast cancer‐related deaths can be attributed to the metastasis of cancer stem cells, chemotherapeutic agents targeting breast cancer stem cells are of interest as a potential treatment. Flavonoids that exhibit cytotoxicity on breast cancer stem cells have rarely been observed. Thus, the objective of this study was to measure potential cytotoxic effects of 42 different flavonoids on the human breast cancer stem‐like cell line, MCF7‐SC. The relationship between flavonoid structural properties and cytotoxicity has not been reported previously; therefore, we determined quantitative structure–activity relationships using both comparative molecular field analysis and comparative molecular similarity analysis. Further biological experiments including Western blot analysis, flow cytometry, and immunofluorescence microscopy were also conducted on the most cytotoxic 8‐chloroflavanone. 相似文献
952.
Hyo Yong Kim Taihua Li Cheulhee Jung Rongzhan Fu Dae-Yeon Cho Ki Soo Park Hyun Gyu Park 《RSC advances》2018,8(65):37391
We herein describe a novel quantitative PCR (qPCR) method, which operates in both signal-off and on manners, by utilizing a unique property of fluorescent nucleobase analogs. The first, signal-off method is developed by designing the primers to contain pyrrolo-dC (PdC), one of the most common fluorescent nucleobase analogs. The specially designed single-stranded primer is extended to form double-stranded DNA during PCR and the fluorescence signal from the PdCs incorporated in the primer is accordingly reduced due to its conformation-dependent fluorescence properties. In addition, the second, signal-on method is devised by designing the primers to contain 5′-overhang sequences complementary to the PdC-incorporated DNA probes. At the initial phase, the PdC-incorporated DNA probes are hybridized to the 5′-overhang sequences of the primer, exhibiting the significantly quenched fluorescence signal, but are detached by either hydrolysis or strand displacement reaction during PCR, leading to the highly enhanced fluorescence signal. This method is more advanced than the first one since it produces signal-on fluorescence response and permits the use of a single PdC-incorporated DNA probe for the detection of multiple target nucleic acids, remarkably decreasing the assay cost. With these novel qPCR methods, we successfully quantified target nucleic acids derived from sexually transmitted disease (STD) pathogens with high accuracy. Importantly, the proposed strategies overcome the major drawbacks in the current SYBR Green and TaqMan probe-based qPCR methods such as low specificity and high assay cost.A novel quantitative PCR (qPCR) method was developed by utilizing a unique property of fluorescent nucleobase analogs (PdCs). 相似文献
953.
Jeong Min Seong Chang Eun Park Mi Young Gi Ju Ae Cha Eun Young Jung Jun Ho Lee Hyun Ho Sung Seung Bum Yang Bae Lee Jae Heon Lim Hyun Yoon 《Primary Care Diabetes》2021,15(3):541-547
AimsThe present study assesses the relationship between uric acid (UA) and lipid accumulation product index (LAP) by gender among Korean adults.MethodsData from 5670 subjects (2463 men and 3207 women) in the Korean National Health and Nutrition Examination Survey (KNHANES VII-1) 2016 were analyzed. LAP was divided into four quartiles (Q1–Q4).ResultsThere were several key findings. Compared with Q1, in the overall population, the odds ratios (ORs) of hyperuricemia (UA ≥ 7.0 mg/dL in men or UA ≥ 6.0 mg/dL in women) were significantly higher in Q2 [1.847 (95% confidence interval [CI], 1.325–2.575)], Q3 [3.050 (95% CI, 2.216–4.198)], and Q4 of LAP [6.367 (95% CI, 4.658–8.704)]. In men, the ORs of hyperuricemia were significantly higher in Q2 [1.658 (95% CI, 1.162–2.367)], Q3 [2.341 (95% CI, 1.656–3.308)], and Q4 [4.633 (95% CI, 3.290–6.525)] than Q1. In women, the ORs of hyperuricemia were significantly higher in Q2 [2.254 (95% CI, 1.085–4.680)], Q3 [5.402 (95% CI, 2.735–10.668)], and Q4 [11.025 (95% CI, 5.620–21.628)] than Q1. In addition, UA levels were positively associated with LAP level in men (r = 0.218; p < 0.001), women (r = 0.261; p < 0.001), and the overall population (r = 0.260; p < 0.001).ConclusionsHyperuricemia was positively associated with LAP in Korean men and women. 相似文献
954.
Jung Won Jeon Soo Jin Kim Jae Young Jang Sun-Moon Kim Chul-Hyun Lim Jae Myung Park Su Jin Hong Chan Gyoo Kim Seong Woo Jeon Si Hyung Lee Jae Kyu Sung Gwang Ho Baik 《Gut and liver》2021,15(2):225
Background/AimsSome cases of gastric low-grade dysplasia (LGD) and high-grade dysplasia (HGD) on forceps biopsy (FB) are diagnosed as gastric cancer (GC) after endoscopic resection (ER). This study aims to evaluate the clinical outcomes of ER for gastric LGD and HGD on pretreatment FB and to identify the factors that predict pathologic upstaging to GC.MethodsPatients who underwent ER for LGD and HGD on pretreatment FB from March 2005 to February 2018 in 14 hospitals in South Korea were enrolled, and the patients’ medical records were reviewed retrospectively.ResultsThis study included 2,150 cases of LGD and 1,534 cases of HGD diagnosed by pretreatment FB. In total, 589 of 2,150 LGDs (27.4%) were diagnosed as GC after ER. Helicobacter pylori infection, smoking history, tumor location in the lower third of the stomach, tumor size >10 mm, depressed lesion, and ulceration significantly predicted GC. A total of 1,115 out of 1,534 HGDs (72.7%) were diagnosed with GC after ER. Previous history of GC, H. pylori infection, smoking history, tumor location in the lower third of the stomach, tumor size >10 mm, depressed lesion, and ulceration were significantly associated with GC. As the number of risk factors predicting GC increased in both LGD and HGD on pretreatment FB, the rate of upstaging to GC after ER increased.ConclusionsA substantial proportion of LGDs and HGDs on pretreatment FB were diagnosed as GC after ER. Accurate ER procedures such as endoscopic submucosal dissection should be recommended in cases of LGD and HGD with factors predicting pathologic upstaging to GC. 相似文献
955.
Poly (lactic acid) (PLA) is the most widely available commercial bioplastic that is used in various medical and packaging applications and three-dimensional filaments. However, because neat PLA is brittle, it conventionally has been blended with ductile polymers and plasticizers. In this study, PLA was blended with the high-ductility biopolymer poly (butylene-sebacate–co–terephthalate) (PBSeT), and hexamethylene diisocyanate (HDI) was applied as a crosslinking compatibilizer to increase the miscibility between the two polymers. PLA (80%) and PBSeT (20%) were combined with various HDI contents in the range 0.1–1.0 parts-per-hundred rubber (phr) to prepare blends, and the resulting physical, thermal, and hydrolysis properties were analyzed. Fourier-transform infrared analysis confirmed that –NH–C=OO− bonds had formed between the HDI and the other polymers and that the chemical bonding had influenced the thermal behavior. All the HDI-treated specimens showed tensile strengths and elongations higher than those of the control. In particular, the 0.3-phr-HDI specimen showed the highest elongation (exceeding 150%) and tensile strength. In addition, all the specimens were hydrolyzed under alkaline conditions, and all the HDI-treated specimens degraded faster than the neat PLA one. 相似文献
956.
Nu Si A. Eom Hong-Baek Cho Hyo-Ryoung Lim Tea-Yeon Hwang Yoseb Song Yong-Ho Choa 《RSC advances》2018,8(52):29995
In this study, the sensing properties of palladium-doped porous silicon (Pd/p-Si) substrates for low-ppm level detection of toxic H2S gas are investigated. A Si substrate with dead-end pores ranging from nano- to macroscale was generated by a combined process of metal-assisted chemical etching (MacE) and electrochemical etching with tuned reaction time, in which nano-Pd catalysts were decorated by E-beam sputtering deposition. The sensing properties of the Pd/p-Si were enhanced as the thickness of the substrate layer increased; along with the resulting variation in surface area, this resulted in superior H2S sensing performances in the low-ppm range (less than 3 ppm), with a detection limit of 300 ppb (sensitivity 30%) at room temperature. Furthermore, the sensor displayed excellent selectivity toward the hazardous H2S molecules in comparison with various other reducing gases, including NO2, CO2, NH3, and H2, showing its potential for application in workplaces or environments affected by other toxic gases. The enhancement in sensing performance was possibly due to the increased dispersion and surface area of Pd nano-catalysts, which led to an increase in chemisorption sites of adsorbate molecules.In this study, the sensing properties of palladium-doped porous silicon (Pd/p-Si) substrates for low-ppm level detection of toxic H2S gas are investigated. 相似文献
957.
Kim Hye Jin Park Mi-Suk Son Jin Woo Han Kyunghwa Lee Jei Hee Kim Jai Keun Paik Hyo Chae 《Abdominal imaging》2019,44(4):1361-1366
Abdominal Radiology - The purpose of this study was to investigate the radiological patterns of secondary sclerosing cholangitis (SSC) following lung transplantation. Fifty-five patients underwent... 相似文献
958.
959.
Matthew Chin Heng Chua Jeong Hoon Lim Raye Chen Hua Yeow 《Assistive technology : the official journal of RESNA》2019,31(1):44-52
The modeling and experimentation of a pneumatic actuation system for the development of a soft robotic therapeutic glove is proposed in this article for the prevention of finger deformities in rheumatoid arthritis (RA) patients. The Rehabilitative Arthritis Glove (RA-Glove) is a soft robotic glove fitted with two internal inflatable actuators for lateral compression and massage of the fingers and their joints. Two mechanical models to predict the indentation and bending characteristics of the inflatable actuators based on their geometrical parameters will be presented and validated with experimental results. Experimental validation shows that the model was within a standard deviation of the experimental mean for input pressure range of 0 to 2 bars. Evaluation of the RA-Glove was also performed on six healthy human subjects. The stress distribution along the fingers of the subjects using the RA-Glove was also shown to be even and specific to the finger sizes. This article demonstrates the modeling of soft pneumatic actuators and highlights the potential of the RA-Glove as a therapeutic device for the prevention of arthritic deformities of the fingers. 相似文献
960.
Yin-Mei Lee Dede S. Sutedja Chun-Tao Wai Yock-Young Dan Myat-Oo Aung Lei Zhou Chee-Leong Cheng Aileen Wee Seng-Gee Lim 《Hepatology International》2008,2(2):196-201
Purpose Tumor necrosis factor-α (TNF-α) is implicated in non-alcoholic steatohepatitis (NASH). Pentoxifylline inhibits TNF-α. We wanted
to evaluate the efficacy of Pentoxifylline on NASH patients.
Methods Patients with biopsy proven NASH and persistently elevated alanine aminotransferase (ALT) greater than 1.5 times the upper
limit of normal were randomized to 3 months of treatment with a step 1 American Heart Association diet and daily exercise
with Pentoxifylline or placebo. Liver function tests, serum lipids and TNF-α, Interleukin 6 (IL-6), and plasma hyaluronic
acid were measured at baseline, at weeks 6 and 12. Categorical data were analyzed by Fisher’s exact test while independent
sample t-test and Mann–Whitney test were used for continuous data.
Results Eleven patients were randomized into the Pentoxifylline and nine to the placebo group. After 3 months of treatment body mass
index (BMI), ALT and aspartate aminotransferase (AST) decreased significantly in both groups. There was no difference between
the two groups in reduction of BMI (P = 0.897). There was significantly greater reduction in AST in the Pentoxifylline group (P = 0.038). There was a trend toward lower ALT level (P = 0.065) in the Pentoxifylline group. TNF-α and IL-6 decreased significantly in both groups after treatment, but there was
no significant difference between the two groups.
Conclusion Three months of Pentoxifylline treatment in combination with diet and exercise results in significantly greater reduction
in AST levels in patients with NASH as compared with controls.
This study was funded by the National Healthcare Group Small Innovative Grant NHG-grant number. RPR/04029. It received ethics
approval by the National Healthcare Group Domain Specific Research Board D-registration number DSRB-D/04/083. 相似文献