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目的建立测定注射用骨肽中15种氨基酸含量的柱前衍生高效液相色谱法。方法色谱柱为ZorbaxEclipseAAA柱(150 mm×4.6 mm,5μm),衍生剂为邻苯二甲醛(自动衍生化进样程序),流动相A为40 mmol/L磷酸二氢钠溶液(pH 7.8),流动相B为乙腈-甲醇-水(45∶45∶10,V/V/V),梯度洗脱,流速为2.0 mL/min,检测波长为338 nm,柱温为40℃。结果门冬氨酸、谷氨酸、丝氨酸、组氨酸、甘氨酸、苏氨酸、精氨酸、丙氨酸、酪氨酸、缬氨酸、甲硫氨酸、苯丙氨酸、异亮氨酸、亮氨酸、赖氨酸的质量浓度均在0.01~1.59 mg/mL范围内与峰面积线性关系良好(r≥0.9976);检测限为0.0083 nmol/μL,定量限为0.025 nmol/μL,稳定性和重复性试验结果的RSD均小于2.0%(n=6);平均加样回收率为92.63%~108.28%,RSD为0.87%~2.66%(n=9);3批样品中氨基酸总含量分别为1.83%,1.75%,1.73%。结论该方法操作简便,准确度高,稳定性和重复性均较好,可用于测定注射用骨肽中15种氨基酸的含量。 相似文献
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The relationship between the contents of 13 amino acids in brain tissues and the progression of NAFLD via C57BL/6 model mice 下载免费PDF全文
Non-alcoholic fatty liver disease (NAFLD) is the steatosis of liver parenchyma unrelated to alcoholism, autoimmunity, and viral infection. It is also a metabolism-related syndrome, which has an unseparated relationship with adipose tissue dysfunction and obesity. Hepatic encephalopathy (HE) is one of the severe complications of chronic liver disease and one of the end-stage syndromes of liver disease. Some researchers have suggested that NAFLD, like other forms of liver injury, may be related to the metabolic disorder of branched-chain amino acids (BCAAs), which have been approved to be associated with HE influencing ammonia and energy metabolism. However, several studies have revealed the relationship among amino acids in serum, HE, and chronic liver disease; there are few studies on the contents of amino acids in brain tissues of an animal model with NAFLD. In the present research, we established a NAFLD mouse model with C57BL/6 mice and determined the contents of 13 amino acids in brain tissues of model mice by HPLC-FLD derivatization method using ortho-phthalaldehyde (OPA) to explore the relationship between the contents of amino acids in brain tissues and the progression of NAFLD. Moreover, the study showed that the changes of amino acid contents in the brain of the C57BL/6 mice were associated with the advancement of NAFLD, and this change might be related to the mechanism of HE. 相似文献
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目的建立牛蛙血细胞核酸及脊髓运动神经细胞显色方法,更好地服务教学和临床。方法制备临时装片,用福尔根反应和甲基绿-派洛宁对细胞内的核酸进行显色,用甲苯胺蓝染液对脊髓运动神经细胞进行染色。结果福尔根反应后,细胞核呈紫红色,细胞质呈绿色。该反应的最适条件为室温水解2 min,60℃水解8 min,再室温水解2 min,复染40 s。甲基绿-派洛宁染色后,细胞核呈蓝色,细胞质呈粉红色。甲苯胺蓝染色后,脊髓运动神经细胞被染成深蓝色。结论福尔根反应中亮绿复染的最适时间为40 s。甲基绿-派洛宁能够对细胞内的DNA和RNA同时进行定位、定性分析。该研究方法对实验教学、科学研究和临床实践具有一定的理论和实际意义。 相似文献
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Lipids are essential for cellular functioning considering their role in membrane composition, signaling, and energy metabolism. The brain is the second most abundant organ in terms of lipid concentration and diversity only after adipose tissue. However, in the central system (CNS) lipid dysregulation has been linked to the etiology, progression, and severity of neurodegenerative diseases such as Alzheimeŕs, Parkinson, and Multiple Sclerosis. Advances in the human genome and subsequent sequencing technologies allowed us the study of lipidomics as a promising approach to diagnosis and treatment of neurodegeneration. Lipidomics advances rapidly increased the amount and quality of data allowing the integration with other omic types as well as implementing novel bioinformatic and quantitative tools such as machine learning (ML). Integration of lipidomics data with ML, as a powerful quantitative predictive approach, led to improvements in diagnostic biomarker prediction, clinical data integration, network, and systems approaches for neural behavior, novel etiology markers for inflammation, and neurodegeneration progression and even Mass Spectrometry image analysis. In this sense, by exploiting lipidomics data with ML is possible to improve the identification of new biomarkers or unveil new molecular mechanisms associated with lipid impairment across neurodegeneration. In this review, we present the lipidomic neurobiology state-of-the-art highlighting its potential applications to study neurodegenerative conditions. Also, we present theoretical background, applications, and advances in the integration of lipidomics with ML. This review opens the door to new approaches in this rising field. 相似文献
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Rou Zhang Wen-Qi Ma Meng-Jun Fu Juan Li Chun-Hua Hu Yi Chen Mi-Mi Zhou Zhi-Jie Gao Ying-Li He 《World Journal of Clinical Cases》2021,9(2):308-320
Bile acids (BAs) are classically known to play a vital role in the metabolism of lipids and in absorption. It is now well established that BAs act as signaling molecules, activating different receptors (such as farnesoid X receptor, vitamin D receptor, Takeda G-protein-coupled receptor 5, sphingosine-1-phosphate, muscarinic receptors, and big potassium channels) and participating in the regulation of energy homeostasis and lipid and glucose metabolism. In addition, increased BAs can impair cardiovascular function in liver cirrhosis. Approximately 50% of patients with cirrhosis develop cirrhotic cardiomyopathy. Exposure to high concentrations of hydrophobic BAs has been shown to be related to adverse effects with respect to vascular tension, endothelial function, arrhythmias, coronary atherosclerotic heart disease, and heart failure. The BAs in the serum BA pool have relevant through their hydrophobicity, and the lipophilic BAs are more harmful to the heart. Interestingly, ursodeoxycholic acid is a hydrophilic BA, and it is used as a therapeutic drug to reverse and protect the harmful cardiac effects caused by hydrophobic elevated BAs. In order to elucidate the mechanism of BAs and cardiovascular function, abundant experiments have been conducted in vitro and in vivo. The aim of this review was to explore the mechanism of BAs in the cardiovascular system. 相似文献
9.
Junryo Rii Shinichi Sakamoto Masahiro Sugiura Manato Kanesaka Ayumu Fujimoto Yasutaka Yamada Maihulan Maimaiti Keisuke Ando Ken Wakai Minhui Xu Yusuke Imamura Norihisa Shindo Toru Hirota Atsushi Kaneda Yoshikatsu Kanai Yuzuru Ikehara Naohiko Anzai Tomohiko Ichikawa 《Cancer science》2021,112(9):3871-3883
L-type amino acid transporter 3 (LAT3, SLC43A1) is abundantly expressed in prostate cancer (PC) and is thought to play an essential role in PC progression through the cellular uptake of essential amino acids. Here, we analyzed the expression, function, and downstream target of LAT3 in PC. LAT3 was highly expressed in PC cells expressing androgen receptor (AR), and its expression was increased by dihydrotestosterone treatment and decreased by bicalutamide treatment. In chromatin immunoprecipitation sequencing of AR, binding of AR to the SLC43A1 region was increased by dihydrotestosterone stimulation. Knockdown of LAT3 inhibited cell proliferation, migration, and invasion, and the phosphorylation of p70S6K and 4EBP-1. Separase (ESPL1) was identified as a downstream target of LAT3 by RNA sequencing analysis. In addition, immunostaining of prostatectomy specimens was performed. In the multivariate analysis, high expression of LAT3 was an independent prognostic factor for recurrence-free survival (hazard ratio: 3.24; P = .0018). High LAT3 expression was correlated with the pathological T stage and a high International Society of Urological Pathology grade. In summary, our results suggest that LAT3 plays an important role in the progression of PC. 相似文献