全文获取类型
收费全文 | 928篇 |
免费 | 47篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 22篇 |
妇产科学 | 14篇 |
基础医学 | 97篇 |
口腔科学 | 37篇 |
临床医学 | 93篇 |
内科学 | 184篇 |
皮肤病学 | 18篇 |
神经病学 | 69篇 |
特种医学 | 18篇 |
外科学 | 138篇 |
综合类 | 16篇 |
一般理论 | 1篇 |
预防医学 | 53篇 |
眼科学 | 79篇 |
药学 | 72篇 |
中国医学 | 6篇 |
肿瘤学 | 50篇 |
出版年
2024年 | 3篇 |
2023年 | 12篇 |
2022年 | 44篇 |
2021年 | 63篇 |
2020年 | 27篇 |
2019年 | 52篇 |
2018年 | 48篇 |
2017年 | 30篇 |
2016年 | 48篇 |
2015年 | 27篇 |
2014年 | 39篇 |
2013年 | 40篇 |
2012年 | 67篇 |
2011年 | 87篇 |
2010年 | 29篇 |
2009年 | 23篇 |
2008年 | 46篇 |
2007年 | 45篇 |
2006年 | 47篇 |
2005年 | 39篇 |
2004年 | 42篇 |
2003年 | 32篇 |
2002年 | 25篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1988年 | 2篇 |
1986年 | 5篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1976年 | 2篇 |
1974年 | 4篇 |
1972年 | 1篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1966年 | 1篇 |
1957年 | 1篇 |
1956年 | 1篇 |
1954年 | 1篇 |
1947年 | 1篇 |
1927年 | 1篇 |
排序方式: 共有980条查询结果,搜索用时 0 毫秒
61.
Cui X Li S Shraim A Kobayashi Y Hayakawa T Kanno S Yamamoto M Hirano S 《Toxicologic pathology》2004,32(1):64-72
Although arsenic exposure causes liver disease and/or hepatoma, little is known about molecular mechanisms of arsenic-induced liver toxicity or carcinogenesis. We investigated the effects of arsenic on expression of cancer-related genes in a rat liver following subchronic exposure to sodium arsenate (1, 10, 100 ppm in drinking water), by using real-time quantitative RT-PCR and immunohistochemical analyses. Arsenic accumulated in the rat liver dose-dependently and caused hepatic histopathological changes, such as disruption of hepatic cords, sinusoidal dilation, and fatty infiltration. A 1-month exposure to arsenic significantly increased hepatic mRNA levels of cyclin D1 (10 ppm), ILK (1 ppm), and p27(Kip1) (10 ppm), whereas it reduced mRNA levels of PTEN (1 ppm) and beta-catenin (100 ppm). In contrast, a 4-month arsenic exposure showed increased mRNA expression of cyclin D1 (100 ppm), ILK (1 ppm), and p27(Kip1) (1 and 10 ppm), and decreased expression of both PTEN and beta-catenin at all 3 doses. An immunohistochemical study revealed that each protein expression accords closely with each gene expression of mRNA level. In conclusion, subchronic exposure to inorganic arsenate caused pathological changes and altered expression of cyclin D1, p27(Kip1), ILK, PTEN, and beta-catenin in the liver. This implies that arsenic liver toxicity involves disturbances of some cancer-related molecules. 相似文献
62.
63.
64.
65.
Sara S. Elmegarhi Justin Z. Amarin Maher T. Hadidi Darwish H. Badran Islam M. Massad Amjad M. Bani-Hani Amjad T. Shatarat 《Anatomical science international / Japanese Association of Anatomists》2018,93(2):238-243
The dorsal metacarpal veins are frequently cannulated. Cannulation success is determined by several variable anatomic features. The objective of this study is to classify, for the first time, the anatomic variants of the dorsal metacarpal veins. In this cross-sectional study, 520 university students and staff were conveniently recruited. The dorsal metacarpal veins in 1040 hands were studied. Venous visibility was enhanced by either tourniquet application or near-infrared illumination. Variant patterns of the dorsal metacarpal veins were classified. The final analysis included 726 hands, for an exclusion rate of 30 %. Eight pattern types were identified. Three anatomic features informed the variation. Bilateral symmetry of the dorsal metacarpal veins was present in 352 participants (83 % of the total). The overall frequency distribution of variants in both hands was similar (P = 0.8). The frequency distribution of variants was subject to sexual dimorphism (P = 0.001), ethnic variation (P < 0.001), and technical variation (P < 0.001). The anatomic variants of the dorsal metacarpal veins were sorted into decreasingly frequent primary, secondary, and tertiary groups. The groups may signify a progressive increase in difficulty of peripheral cannulation, in the mentioned order. As such, primary patterns are the most common and likely the easiest to cannulate, while tertiary patterns are the least common and likely the most difficult to cannulate. The preceding premise, in tandem with the bilateral asymmetry of the veins, is clinically significant. With cannulation difficulty likely signifying an underlying tertiary pattern, the contralateral dorsal metacarpal veins are probabilistically characterized by a primary pattern and are, as such, the easier option for peripheral venous cannulation. 相似文献
66.
Raja Amjad Waheed Khan Jianhua Chen Meng Wang Zujia Wen Jiawei Shen Zhijian Song 《The world journal of biological psychiatry》2016,17(2):140-146
Objectives The SLCO6A1 gene belongs to a superfamily of genes which is known to be a solute carrier family of OATPs (SLCO). The SLCO6A1 gene encodes OATP6A1 protein in humans. A previous genome-wide association study (GWAS) of schizophrenia conducted in the Swedish population demonstrated a significant association of rs6878284, which is located in the SLCO6A1 gene, with schizophrenia. To further investigate whether this gene is also a risk locus for schizophrenia (SCZ), bipolar disorder (BPD) and major depressive disorder (MDD) in the Han Chinese population, a case–control study was designed. Methods In total 1,248 unrelated SCZ cases, 1,344 BPD cases, 1,056 unrelated MDD cases and 1,248 normal controls were analysed in this study. We genotyped five SNPs using the Sequenom MassARRAY platform. Results We found no association of rs6878284 with SCZ [Corrected Pallele?=?0.969, Corrected Pgenotype?=?0.997]. Furthermore, we found a statistically significant association of the rs7734060 genotype with MDD after correction [rs7734060: Corrected Pallele?=?0.114, Corrected Pgenotype?=?0.036] in the Han Chinese population. Conclusions This is the first study which reveals no association of rs6878284 with SCZ and also predicts that rs7734060 could be a risk locus for MDD in the Han Chinese population. 相似文献
67.
Irfanullah Khan Amer Hayat Khan Azreen Syazril Adnan Syed Azhar Syed Sulaiman Azhar Bin Amir Hamzah Nafees Ahmed Amjad Khan 《International urology and nephrology》2018,50(6):1113-1121
Purpose
Creatinine is normally used to evaluate kidney function among elderly patients in clinical practice, which has been reported to be affected by socio-demographic factors like BMI and age. Cystatin C a newly introduced biomarker may be more efficient in identifying kidney function in obese and aged CKD patients. The aim of the current study was to assess the effect of BMI on endogenous biomarkers (cystatin C and creatinine) among elderly CKD patients in Malaysia, a first such study in the country.Methods
The current study was conducted at the Hospital University Sains Malaysia, Kelantan. A total of 300 elderly Malay participants ≥?65 years, with CKD, were taken in study. Demographic data, blood pressure, weight, and height were documented. Serum creatinine was assayed by Chemistry Analyzer Model Architect-C8000 (Jaffe Method), while serum cystatin C was examined by Human cystatin C ELISA kit (Sigma-Aldrich) using Thermo Scientific Varioskan Flash ELISA reader.Results
The study participants were divided into three groups on the basis of age. There was a statistically significant difference at the p value?<?0.05 in serum creatinine level for the three age groups [F (2, 297)?=?1.98, p value 0.045]. Patients were divided into four groups on the basis of BMI. The results of one-way ANOVA revealed a statistically significant difference at the p value?<?0.05 in the mean serum creatinine level for the four groups [F (3, 396)?=?2.99, p value 0.032]. However, no statistically significant differences between mean serum cystatin C levels were observed on the basis of patient’s age and BMI.Conclusion
Cystatin C is not related to BMI and age among elderly chronic kidney disease patients. The study clearly evaluates the role of serum cystatin C as a good competitor of creatinine among the elderly CKD patients.68.
The objective of this study was to investigate whether the miscibility of a drug and coformer, as predicted by Hansen solubility parameters (HSPs), can indicate cocrystal formation and guide cocrystal screening. It was also our aim to evaluate various HSPs-based approaches in miscibility prediction. HSPs for indomethacin (the model drug) and over thirty coformers were calculated according to the group contribution method. Differences in the HSPs between indomethacin and each coformer were then calculated using three established approaches, and the miscibility was predicted. Subsequently, differential scanning calorimetry was used to investigate the experimental miscibility and cocrystal formation. The formation of cocrystals was also verified using liquid-assisted grinding. All except one of the drug-coformers that were predicted to be miscible were confirmed experimentally as miscible. All tested theoretical approaches were in agreement in predicting miscibility. All systems that formed cocrystals were miscible. Remarkably, two new cocrystals of indomethacin were discovered in this study. Though it may be necessary to test this approach in a wide range of different coformer and drug compound types for accurate generalizations, the trends with tested systems were clear and suggest that the drug and coformer should be miscible for cocrystal formation. Thus, predicting the miscibility of cocrystal components using solubility parameters can guide the selection of potential coformers prior to exhaustive cocrystal screening work. 相似文献
69.
Kasperkovitz PV Khan NS Tam JM Mansour MK Davids PJ Vyas JM 《Infection and immunity》2011,79(12):4858-4867
Phagocytic responses are critical for effective host defense against opportunistic fungal pathogens. Macrophages sample the phagosomal content and orchestrate the innate immune response. Toll-like receptor 9 (TLR9) recognizes unmethylated CpG DNA and is activated by fungal DNA. Here we demonstrate that specific triggering of TLR9 recruitment to the macrophage phagosomal membrane is a conserved feature of fungi of distinct phylogenetic origins, including Candida albicans, Saccharomyces cerevisiae, Malassezia furfur, and Cryptococcus neoformans. The capacity to trigger phagosomal TLR9 recruitment was not affected by a loss of fungal viability or cell wall integrity. TLR9 deficiency has been linked to increased resistance to murine candidiasis and to restriction of fungal growth in vivo. Macrophages lacking TLR9 demonstrate a comparable capacity for phagocytosis and normal phagosomal maturation compared to wild-type macrophages. We now show that TLR9 deficiency increases macrophage tumor necrosis factor alpha (TNF-α) production in response to C. albicans and S. cerevisiae, independent of yeast viability. The increase in TNF-α production was reversible by functional complementation of the TLR9 gene, confirming that TLR9 was responsible for negative modulation of the cytokine response. Consistently, TLR9 deficiency enhanced the macrophage effector response by increasing macrophage nitric oxide production. Moreover, microbicidal activity against C. albicans and S. cerevisiae was more efficient in TLR9 knockout (TLR9KO) macrophages than in wild-type macrophages. In conclusion, our data demonstrate that TLR9 is compartmentalized selectively to fungal phagosomes and negatively modulates macrophage antifungal effector functions. Our data support a model in which orchestration of antifungal innate immunity involves a complex interplay of fungal ligand combinations, host cell machinery rearrangements, and TLR cooperation and antagonism. 相似文献
70.