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51.
Carnosic acid induces autophagic cell death through inhibition of the Akt/mTOR pathway in human hepatoma cells 下载免费PDF全文
Qilong Gao Huaimin Liu Yamin Yao Liang Geng Xinfeng Zhang Lifeng Jiang Bian Shi Feng Yang 《Journal of applied toxicology : JAT》2015,35(5):485-492
The therapeutic goal of cancer treatment is now geared towards triggering tumour‐selective cell death with autophagic cell death being required for the chemotherapy of apoptosis‐resistant cancer. In this study, Carnosic acid (CA), a polyphenolic diterpene isolated from Rosemary (Rosemarinus officinalis), significantly induced autophagic cell death in HepG2 cells. Ca treatment caused the formation of autophagic vacuoles produced an increasing ratio of LC3‐II to LC3‐I in a time‐ and dose‐dependent manner but had no effect on the levels of autophagy‐related protein ATG6 and ATG13 expression. Autophagy inhibitors, 3‐methyladenine (3‐MA), chloroquine and bafilomycin A1, or ATG genes silencing in HepG2 cells significantly inhibited CA‐induced autophagic cell death. The CA treatment decreased the levels of phosphorylated Akt and mTOR without any effects on PI3K or PTEN. Most importantly, overexpression of Akt and knockdown of PTEN attenuated autophagy induction in CA‐treated cells. Taken together, our results indicated that CA induced autophagic cell death through inhibition of the Akt/mTOR pathway in human hepatoma cells. These findings suggest that CA has a great potential for the treatment of hepatoma via autophagic induction. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
52.
Canqing Yu Zumin Shi Jun Lv Huaidong Du Lu Qi Yu Guo Zheng Bian Liang Chang Xuefeng Tang Qilian Jiang Huaiyi Mu Dongxia Pan Junshi Chen Zhengming Chen Liming Li 《Nutrients》2015,7(7):5834-5849
Limited evidence exists for the association between diet pattern and obesity phenotypes among Chinese adults. In the present study, we analyzed the cross-sectional data from 474,192 adults aged 30–79 years from the China Kadoorie Biobank baseline survey. Food consumption was collected by an interviewer-administered questionnaire. Three dietary patterns were extracted by factor analysis combined with cluster analysis. After being adjusted for potential confounders, individuals following a traditional southern dietary pattern had the lowest body mass index (BMI) and waist circumference (WC); the Western/new affluence dietary pattern had the highest BMI; and the traditional northern dietary pattern had the highest WC. Compared to the traditional southern dietary pattern in multivariable adjusted logistic models, individuals following a Western/new affluence dietary pattern had a significantly increased risk of general obesity (prevalence ratio (PR): 1.06, 95% confidence interval (CI): 1.03–1.08) and central obesity (PR: 1.07, 95% CI: 1.06–1.08). The corresponding risks for the traditional northern dietary pattern were 1.05 (1.02–1.09) and 1.17 (1.25–1.18), respectively. In addition, the associations were modified by lifestyle behaviors, and the combined effects with alcohol drinking, tobacco smoking, and physical activity were analyzed. Further prospective studies are needed to elucidate the diet-obesity relationships. 相似文献
53.
目的 评估妊娠中期羊水间期细胞荧光原位杂交(fluorescence in situ hybridization,FISH)检测后漏诊非13、18、21、X或Y染色体非整倍体异常核型的残余风险. 方法 对中国医学科学院北京协和医学院北京协和医院2010年1月1日至2013年7月31日2 837例妊娠中期行羊膜腔穿刺术同时行间期细胞FISH检测和传统核型分析的病例及其结果进行回顾性分析.采用GLP 13/GLP21/CSP 18/CSPX/CSPY探针针对13、18、21、X或Y染色体进行间期细胞FISH检测.计算具有三大产前诊断指征(孕妇高龄、母体血清学筛查18或21-三体高风险、妊娠23周前超声发现胎儿有结构异常)的孕妇间期细胞FISH检测的检出率以及残余风险. 结果 2 837例标本中,共85例(3.0%)羊水细胞染色体核型分析异常.85例中的73例为13、18、21、X或Y染色体非整倍体的异常核型,间期细胞FISH结果均为阳性,其中21-三体共43例(包括2例嵌合体)、18-三体1 5例、13-三体l例、性染色体非整倍体14例(包括4例嵌合体).12例(14.1%)异常结果为非13、1 8、21、X或Y染色体的非整倍体,包括平衡性结构重排6例、非平衡性结构重排5例、其他染色体非整倍体1例.这12例中,间期细胞FISH结果阳性3例,均涉及21号染色体的不平衡性结构异常;阴性9例,其中4例遗传性平衡性重排和2例新生平衡性重排.2 837例病例间期细胞FISH分析对染色体异常的检出率为89.4%(76/85),异常核型漏诊率为14.1%(12/85),残余风险为0.43%(12/2 761). 结论 间期细胞FISH检测是核型分析的有效补充,但不能取代核型分析,单纯间期细胞FISH检测进行产前诊断可能漏诊部分染色体结构异常.在产前遗传咨询时,应向患者解释间期细胞FISH的检出率和残余风险,合理选择产前诊断方法. 相似文献
54.
Bing-Quan Yang Yang Lu Jia-Jia He Tong-Zhi Wu Zuo-Ling Xie Cheng-Hao Lei Yi Zhou Jing Han Mei-Qi Bian Hong You De-Xian Mei Zi-Lin Sun 《中华医学杂志(英文版)》2015,128(24):3270-3275
Background:
The conventional approaches to diabetes screening are potentially limited by poor compliance and laboratory demand. This study aimed to evaluate the performance of fasting plasma glucose (FPG) and postprandial urine glucose (PUG) in screening for diabetes in Chinese high-risk population.Methods:
Nine hundred and nine subjects with high-risk factors of diabetes underwent oral glucose tolerance test after an overnight fast. FPG, hemoglobin A1c, 2-h plasma glucose (2 h-PG), and 2 h-PUG were evaluated. Diabetes and prediabetes were defined by the American Diabetes Association criteria. The area under the receiver operating characteristic (ROC) curve was used to evaluate the diagnostic accuracy of 2 h-PUG, and the optimal cut-off determined to provide the largest Youden index. Spearman correlation was used for relationship analysis.Results:
Among 909 subjects, 33.4% (304/909) of subjects had prediabetes, and 17.2% (156/909) had diabetes. The 2 h-PUG was positively related to FPG and 2 h-PG (r = 0.428 and 0.551, respectively, both P < 0.001). For estimation of 2 h-PG ≥ 7.8 mmol/L and 2 h-PG ≥ 11.1 mmol/L using 2 h-PUG, the area under the ROC curve were 0.772 (95% confidence interval [CI ]: 0.738–0.806) and 0.885 (95% CI: 0.850–0.921), respectively. The corresponding optimal cut-offs for 2 h-PUG were 5.6 mmol/L and 7.5 mmol/L, respectively. Compared with FPG alone, FPG combined with 2 h-PUG had a higher sensitivity for detecting glucose abnormalities (84.1% vs. 73.7%, P < 0.001) and diabetes (82.7% vs. 48.1%, P < 0.001).Conclusion:
FPG combined with 2 h-PUG substantially improves the sensitivity in detecting prediabetes and diabetes relative to FPG alone, and may represent an efficient layperson-oriented diabetes screening method. 相似文献55.
边立忠 《中国实用神经疾病杂志》2015,(3):49-50
目的探讨显露喉返神经(RLN)在甲状腺根治术中的应用。方法收集甲状腺癌根治术患者260例,随机分为观察组与对照组各130例,观察组术中显露RLN,对照组术中不显露RLN,比较2组手术效果。结果观察组RLN损伤发生率1.54%,显著低于对照组的10.77%(P0.05);2组手术时间、术中出血量无明显差异(P0.05),观察组淋巴结清扫数显著高于对照组(P0.05)。结论在甲状腺癌根治术中显露RLN,能够保护RLN,降低RLN损伤发生率,可提高手术效果,值得推广应用。 相似文献
56.
Meng-qi Liu Zhi-ye Chen Xiang-bing Bian Meng-yu Liu Shen-yuan Yu Lin Ma 《中国医学科学杂志(英文版)》2015,(1):34-36
Objective To investigate the changes of lateral geniculate body(LGB) in the normal aging brain using quantitative susceptibility mapping(QSM) technique. Methods Magnetic resonance(MR) phase and magnitude images were acquired from enhanced gradient echo T2 star weighted angiography sequence with 16 echoes on 3.0T MR system using the head coil with 32 channels. Morphology Enabled Dipole Inversion(MEDI) method was applied for QSM, and the susceptibility value of LGB was measured by region of interest(ROI) drawn manually on three orthogonal planes. Results LGB of the middle-aged group had a higher susceptibility value(0.16±0.05 ppm) than that of the youth group(0.12±0.05 ppm) and elderly group(0.13±0.03 ppm)(all P<0.05). Partial correlation analysis demonstrated that there was significantly positive correlation between susceptibility value and age in the youth group(r=0.71, P<0.05). Conclusion LGB could clearly be identified on QSM in the brain in vivo. 相似文献
57.
SEMA3F prevents metastasis of colorectal cancer by PI3K–AKT‐dependent down‐regulation of the ASCL2–CXCR4 axis 下载免费PDF全文
Feng Wu Juan Tan Sen‐lin Xu Yanqing Ding Na Zhan Xu‐gang Hu You‐hong Cui Xia Zhang Weiguo Dong Xin‐dong Liu Xiu‐wu Bian 《The Journal of pathology》2015,236(4):467-478
Semaphorin‐3F (SEMA3F), an axonal repulsant in nerve development, has been shown to inhibit the progression of human colorectal cancer (CRC); however, the underlying mechanism remains elusive. In this study we found a negative correlation between the levels of SEMA3F and CXCR4 in CRC specimens from 85 patients, confirmed by bioinformatics analysis of gene expression in 229 CRC samples from the Cancer Genome Atlas. SEMA3Fhigh/CXCR4low patients showed the lowest frequency of lymph node and distant metastasis and the longest survival. Mechanistically, SEMA3F inhibited the invasion and metastasis of CRC cells through PI3K–AKT‐dependent down‐regulation of the ASCL2–CXCR4 axis. Specifically, ASCL2 enhanced the invasion and metastasis of CRC cells in vitro and expression of ASCL2 correlated with distant metastasis, tumour size and poor overall survival in CRC patients. Treatment of CRC cells with the CXCR4 antagonist AMD3100 attenuated SEMA3F knockdown‐induced invasion and metastasis of CRC cells in vitro and in vivo. Our study thus demonstrates that SEMA3F functions as a suppressor of CRC metastasis via down‐regulating the ASCL2–CXCR4 axis. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
58.
Hai-tao Zhu Chen Bian Ji-chao Yuan Xiao-jun Liao Wei Liu Gang Zhu Hua Feng Jiang-kai Lin 《Critical care (London, England)》2015,19(1)
IntroductionIntracerebral hemorrhage (ICH) at high altitude is not well understood to date. This study investigates the effects of high altitude on ICH, and examines the acute neuroprotection of hyperbaric oxygen (HBO) therapy against high-altitude ICH.MethodsMinipigs were placed in a hypobaric chamber for 72 h before the operation. ICH was induced by an infusion of autologous arterial blood (3 ml) into the right basal ganglia. Animals in the high-altitude ICH group received HBO therapy (2.5 ATA for 60 min) 30 min after ICH. Blood gas, blood glucose and brain tissue oxygen partial pressure (PbtO2) were monitored continuously for animals from all groups, as were microdialysis products including glucose, lactate, pyruvate and glutamate in perihematomal tissue from 3 to 12 h post-ICH.ResultsHigh-altitude ICH animals showed significantly lower PbtO2, higher lactate/pyruvate ratio (LPR) and glutamate levels than low-altitude ICH animals. More severe neurological deficits, brain edema and neuronal damage were also observed in high-altitude ICH. After HBO therapy, PbtO2 was significantly increased and LPR and glutamate levels were significantly decreased. Brain edema, neurological deficits and neuronal damage were also ameliorated.ConclusionsThe data suggested a more serious disturbance of tissue oxygenation and cerebral metabolism in the acute stage after ICH at high altitude. Early HBO treatment reduced acute brain injury, perhaps through a mechanism involving the amelioration of the derangement of cerebral oxygenation and metabolism following high-altitude ICH. 相似文献
59.
Anti‐fibrotic and Anti‐tumorigenic Effects of Rhein,a Natural Anthraquinone Derivative,in Mammalian Stellate and Carcinoma Cells 下载免费PDF全文
Anthraquinone compounds have been recognized to possess antiinflammatory, anti‐fibrotic and anti‐tumour properties and thus applied in human and veterinary therapeutics as active substances of medicinal products. Amongst the anthraquinones isolated from Rheum palmatum, also known as da‐huang, rhein was detected as one of the highest metabolite contents in the bloodstream of mammals. The biological activities of rhein therefore deserve detailed investigation. In this study, we aimed to delineate the mechanism of inhibitory actions of rhein on fibrotic and tumorigenic processes by means of various biochemical assays, such as immunofluorescent staining, real‐time polymerase chain reaction (PCR) and western blotting analyses in rat pancreatic stellate cells (LTC‐14), human pancreatic ductal adenocarcinoma cells (PANC‐1) and human colon carcinoma cells (SW480 and SW620). Our results demonstrated that the application of rhein notably suppressed the mRNA and protein levels of various fibrotic and tumorigenic mediators including alpha‐smooth muscle actin, type I collagen, fibronectin, N‐cadherin and matrix metalloproteinases in the testing mammalian cells. The mechanism of the suppressive actions of rhein was associated with the modulation of the sonic hedgehog and serine‐threonine kinase signalling pathways. In conclusion, we suggest that rhein may serve as a therapeutic or an adjuvant agent in anti‐fibrotic and anti‐tumorigenic approaches. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
60.
Chen-qing Liu Xiao-ting Cheng Yu-hua Zhu Wei-dong Shen Bo-wen Bian Ju-yang Cao 《Acta oto-laryngologica》2015,135(5):451-458
Conclusion: The hearing conditions of the centenarians were quite poor as regards hearing thresholds and speech detection ability. Objective: To investigate hearing conditions of centenarians. Methods: A total of 54 centenarians in Rizhao and Linyi Districts in Shandong Province were investigated to assess hearing conditions of centenerians comprehensively by questionnaire investigation, pure-tone audiometry, acoustic immitance, intelligence evaluation, and speech detection scores. Also, 135 individuals were recruited as controls and divided into four groups according to their age: 45–59 years, 60–69 years, 70–79 years, and 80–89 years. Results: The hearing thresholds of the centenarians were dramatically higher than those of the control group (p < 0.05) and all centenarians suffered moderate to profound hearing loss according to the World Health Organization (WHO) criteria. Few centenarians had normal level of speech detection scores. All centenarians showed descending hearing curve, and the hearing threshold of the male centenarians at 8000 Hz was higher than that of the females (p = 0.047). There was a significant air–bone conduction gap in the centenarians (p < 0.05). 相似文献