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51.
C/EBP is a sequence-specific DNA-binding protein.In order to identify its distribu-tion,localization and function,immunocytochemical technique(ABC method)was done usinganti-C/EBP polypeptide antibodies 1103~#,425~# in liver specimens from 20 normal adult,5neonatal,6 patients with hepatitis,25 patients with liver cirrhosis,80 patients with hepatocellu-lar carcinoma(40 cases were associated with surrounding nontumorous tissues)and 26 patientswith cholangiocarcinoma(15 cases were associated with surrounding nontumorous tissues).Theresults showed that C/EBP was diffusely distributed in nuclei and cytoplasm of differentiated liv-er cells and very low or undetectable in liver cancer cells.The expression of C/EBP was in pro-portion to differentiated degree of tumor cells,and was obviously weaker than that in surround-ing nontumorous tissues.C/EBP positive staining has also been found in regenerating epithelialcells of bile ductules.The results suggested that C/EBP might play an important role in estab-lishing and maintaining the differentiation of liver cells and might exert an inhibiting effect againsttransformation of liver cells and proliferation of neoplastic tissue. 相似文献
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53.
Menthol, the cooling natural product of peppermint, is widely used in medicinal preparations for the relief of acute and inflammatory pain in sports injuries, arthritis, and other painful conditions. Menthol induces the sensation of cooling by activating TRPM8, an ion channel in cold-sensitive peripheral sensory neurons. Recent studies identified additional targets of menthol, including the irritant receptor, TRPA1, voltage-gated ion channels and neurotransmitter receptors. It remains unclear which of these targets contribute to menthol-induced analgesia, or to the irritating side effects associated with menthol therapy. Here, we use genetic and pharmacological approaches in mice to probe the role of TRPM8 in analgesia induced by L-menthol, the predominant analgesic menthol isomer in medicinal preparations. L-menthol effectively diminished pain behavior elicited by chemical stimuli (capsaicin, acrolein, acetic acid), noxious heat, and inflammation (complete Freund’s adjuvant). Genetic deletion of TRPM8 completely abolished analgesia by L-menthol in all these models, although other analgesics (acetaminophen) remained effective. Loss of L-menthol–induced analgesia was recapitulated in mice treated with a selective TRPM8 inhibitor, AMG2850. Selective activation of TRPM8 with WS-12, a menthol derivative that we characterized as a specific TRPM8 agonist in cultured sensory neurons and in vivo, also induced TRPM8-dependent analgesia of acute and inflammatory pain. L-menthol– and WS-12–induced analgesia was blocked by naloxone, suggesting activation of endogenous opioid-dependent analgesic pathways. Our data show that TRPM8 is the principal mediator of menthol-induced analgesia of acute and inflammatory pain. In contrast to menthol, selective TRPM8 agonists may produce analgesia more effectively, with diminished side effects. 相似文献
54.
55.
为探讨牙周病发病的危险因素 ,作者在武汉市机关干部体检中对 193对牙周病患者进行 1∶ 1配比的病例对照研究。结果表明 ,牙结石、吸烟、饮酒是牙周病的危险因素 ,其 OR值分别为5.31、2 .13和 1.86;未发现饮茶与牙周病的发病有统计学联系。吸烟与牙结石在牙周病致病过程中呈协同作用 ,OR值高达 18.92。牙周病归因于饮酒、吸烟及牙结石的暴露人群归因危险百分比分别为 4 6.2 4 %、53.31%及 81.17% ,总体人群归因危险百分比分别为 2 5.12 %、2 4 .0 4 %及 4 6.2 9%。 相似文献
56.
目的以IMC-038525为先导化合物,设计并合成4-苯基-1,3,5-三嗪-2-胺类化合物,考察其体外抗肿瘤活性。方法以2,4-二氯-1,3,5-三嗪为起始原料,经过氨化、Suzuki偶联和还原胺化合成一类4-苯基-1,3,5-三嗪-2-胺类化合物,采用噻唑蓝法(MTT)测定其对肿瘤细胞的抑制活性。结果设计并合成了13个新化合物,结构经1H-NMR和MS确证。活性测试结果显示该类化合物具有一定的抗肿瘤活性。结论合成了一类4-苯基-1,3,5-三嗪-2-胺类衍生物,具有一定抑瘤活性的化合物,为新型抗肿瘤化合物的设计与合成提供思路。 相似文献
57.
雷公藤倍半萜生物碱的研究 总被引:13,自引:0,他引:13
目的 研究雷公藤(Tripterygium wilfordii Hook.f.)的化学成分。方法 应用各种色谱技术进行分离纯化,用UV,IR,MS,HRMS,1HNMR,13CNMR(COM和OFR),1H-1HCOSY,1H-13CCOSY,2D-NOESY,1H-13CCOLOC鉴定化合物。并进行初步的药理实验。结果 分离并鉴定了2个生物碱:euonine(I)和雷公藤康碱(IIwilfordconine)。结论 II为一种新的倍半萜生物碱,药理实验证明该生物碱有免疫抑制活性,并对白血病细胞有抑制作用。 相似文献
58.
Liao Xiang-bin廖翔嫔 Zhang Ji-hong张季鸿 Lu Xue-ying路雪英and Sui Shu-jing隋淑静 Tianin Children''s Hospital Tianjin 《中华医学杂志(英文版)》1984,97(2):141-142
1,330 autopsies performed at the Pathology
Department of this hospital during 1958.-1981,
including 415 newborns, a.re studied. Among
the 371 cases of congenital anomalies (110 new-
borns), 173 were congenital cardiovascular
anomalies (66 newborns), a 13% morbidity
forming 46.5'70 0f all congenital anomalies seen.
The 66 nowborns were 6070 0f all neonatal clan-
genital anamalies and 38.2To of all cardiovascular
anomaLies. Fetal stage diagnosis and early ter-
mination of pregnancy when necessary is the
treatment of choice. 相似文献
59.
Li Zhan Xie Xinfang Zhang Xue Shi Sufang Liu Lijun Chen Pei Sui Guili Lyu Jicheng Zhang Hong 《中华肾脏病杂志》2019,35(2):81-87
Objective To establish the measurement of IgA1 O-glycan-specific antiglycan autoantibodies in patients with IgA nephropathy (IgAN), and evaluate their role in the development and progression of IgAN. Methods In the IgAN regular follow-up cohort of Peking University Institute of Nephrology from January 2006 to December 2015, 170 patients drawn by stratified randomization were enrolled in this study. Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of plasma galactose-deficient IgA1 (Gd-IgA1) and antiglycan autoantibody (IgG and IgA1). The correlation between antiglycan autoantibodies and clinicopathological parameters was analyzed by linear correlation and multiple linear regression analysis. The receiver operating characteristic curve (ROC) was used to evaluate the value of plasma anti glycide antibodies in the diagnosis of IgAN. Results IgG and IgA1 antiglycan autoantibodies that specifically recognized Fab-hinge region (Fab-HR) antigens could be detected in both IgAN and healthy control group. Agglutinin inhibition test showed that the specific antigen epitope was N-acetylgalactosamine (GalNAc) residue exposed to galactose deficiency in IgA1 hinged region. There was no significant difference in the absolute levels of plasma IgG antiglycan autoantibodies between IgAN and healthy controls (P=0.963). After adjustment of the plasma level of IgG, the normalized antiglycan autoantibody (ln[IgG antiglycan antibody/IgG]) in patients with IgAN was significantly higher than that in healthy controls (0.58±0.31 vs 0.37±0.11, P﹤0.01). The normalized level of IgG antiglycan autoantibody in IgAN patients was positively correlated with 24 h urine protein level during renal biopsy (Spearman r=0.183, P﹤0.05), and was also significantly correlated with 24 h urinary protein level after adjusting for baseline clinical and pathological factors (β=0.713, 95%CI 0.323-1.102, P﹤0.01). The area under ROC curve (AUC) of normalized IgG antiglycan autoantibody in the diagnosis of IgAN was 0.764 (95% CI 0.682-0.845, P﹤0.05). Using the cut-off value of 0.396, the sensitivity and specificity of normalized IgG antiglycan autoantibody for IgAN were 0.729 and 0.700 respectively. There was no significant difference in the absolute or normalized levels of IgA1 antiglycan autoantibodies between IgAN patients and healthy controls. Conclusions Gd-IgA1-specific antiglycan autoantibodies can be detected both in IgAN patients and healthy controls. They are elevated in some patients with IgAN and possibly involved in the development of IgAN. 相似文献
60.
目的比较2型糖尿病患者与血糖正常者体内血清25-羟维生素D(25-OH Vit D)水平的差异,分析25-羟维生素D与2型糖尿病的关系。方法选择2013年7月~2014年11月在我科住院的2型糖尿病患者50例为病例组,同期在我科住院的血糖正常者60例为对照组。测定25-OH Vit D及相关临床生化指标并统计分析。结果血清25-OH Vit D在病例组和对照组中存在统计学差异(P<0.05),血清25-OH Vit D与空腹血糖呈负相关(P<0.05)。结论血清25-OH Vit D在2型糖尿病患者中低于血糖正常者。且血清25-OH Vit D与空腹血糖呈负相关,即空腹血糖越高,血清25-OH Vit D越低。 相似文献