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991.
Juewon Kim Young‐Gyu Kang Dong‐hwa Choi Young‐uk Cho Si‐young Cho Hyunjung Choi Hyoung‐June Kim 《Experimental dermatology》2019,28(11):1270-1278
Ageing is characterized by the accumulation of chronic and irreversible oxidative damage, chronic inflammation and organ dysfunction. To attenuate these ageing‐related changes, various natural phytochemicals are often applied. Trans‐communic acid (TCA), an active component of brown pine leaf extract, has antimicrobial and cancer chemopreventive activity and inhibits ultraviolet B (UVB)‐induced MMP‐1 expression. To determine whether the phytochemical TCA could affect the lifespan of an ageing model, Caenorhabditis elegans prevent ageing‐related phenotypes of the skin. Caenorhabditis elegans (C. elegans) wild‐type N2 and mutant strains were used in this study to explore the lifespan extension effect of TCA and its mechanism. We estimated lipofuscin accumulation and melanin levels, which are closely associated with skin senescence. Moreover, we explored the mechanism of action associated with ageing attenuation. We performed oxidative stress resistance and thermotolerance assays in C. elegans and surface plasmon resonance analysis of TCA binding with the forkhead box‐O3a (FoxO3a) protein. TCA, which is the active component in Korean red pine (Pinus densiflora), attenuated ageing‐related changes in skin cells. TCA lowered lipofuscin accumulation in fibroblasts and decreased melanin levels in melanocytes. These protective effects were mediated by activation of the representative longevity gene FoxO3a, which was induced by direct binding with TCA. Interestingly, TCA extended the lifespan of C. elegans, although it did not affect stress resistance, oxidative stress or thermotolerance. These results strongly suggest that TCA prevents the senescent phenotype of model organisms and exhibits beneficial effects on ageing‐related skin phenotypes through direct FoxO3a activation. 相似文献
992.
S. W. Choi W. S. Park J. M. Yang C. S. Kang H. S. Sun B. S. Kim E. J. Seo M. J. Lee C. S. Park 《Journal of Korean medical science》1994,9(4):299-303
Gene alterations of p53 tumor suppressor gene such as point mutations, deletions or insertions occur in various human cancers. p53 protein overexpression was studied immunohistochemically in 80 gastric adenocarcinomas using an anti-human p53 antibody (Pab 1801) and the avidin-biotin-peroxidase technique. We have also analyzed allele loss of the human p53 gene in 54 cases of gastric adenocarcinoma using polymerase chain reaction and restriction fragment length polymorphism. p53 immunostaining was also demonstrated in 48 of 80 carcinomas (60%). Normal mucosa was always negative. No relation could be found between p53 immunostaining and the degree of differentiation. 21 of the 54 patients(39%) were informative for the p53 exon 4. In ten of these informative cases(47.6%), tumor DNAs showed allele loss when compared with nonmetastatic lymph node DNAs. Seven of the ten(70%) showed p53 immunoreactivity. These findings suggest that mutations of the p53 gene may play a role in the development of gastric adenocarcinoma and that allele loss of p53 frequently occurs in p53 immunoreactive gastric adenocarcinoma. 相似文献
993.
Hyo-Sun You Jae-woo Lee Ye-seul Kim Yonghwan Kim Hyeong-Cheol Lee Jin Young Hwang Woojung Yang Hee-Taik Kang 《Journal of Korean medical science》2021,36(13)
BackgroundThe 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is a metabolite of tobacco-specific lung carcinogen that can be found in both smokers and non-smokers. Particularly, NNAL levels of children with a history of exposure to second-hand smoke (SHS) are higher than those of adults. Thus, we aimed to investigate the association between SHS exposure and urine NNAL levels in Korean adolescents.MethodsThis cross-sectional study used data from the Korea National Health and Nutrition Examination Survey VII. Overall, 648 never-smoking adolescents (425 boys and 223 girls) aged 12 to 18 were included in this study. Logistic regression analyses identified the relationship between SHS exposure and elevated urine NNAL levels.ResultsThe mean urine NNAL levels of the no exposure and exposure group in boys were 1.39 and 2.26 ng/mL, respectively, whereas they were 1.01 and 2.45 ng/mL in girls, respectively (P < 0.001). Among the adolescents exposed to SHS, the confounder-adjusted odds ratio (95% confidence intervals) for elevated urine NNAL levels according to exposure area as overall, home, and public area were 2.68 (1.58–4.53), 31.02 (9.46–101.74), and 1.89 (1.12–3.17) in boys; and 6.50 (3.22–13.11), 20.09 (7.08–57.04), and 3.94 (1.98–7.77) in girls, respectively.ConclusionSHS exposure was significantly associated with elevated urine NNAL levels in Korean adolescents, particularly in female adolescents and in those with home exposure. These findings remind us of the need to protect adolescents from SHS. 相似文献
994.
Kim SY Sohn EJ Kim DW Jeong HJ Kim MJ Kang HW Shin MJ Ahn EH Kwon SW Kim YN Kwon HJ Kim TY Lee KS Park J Eum WS Choi SY 《The Journal of investigative dermatology》2011,131(7):1477-1485
Immunophilin, FK506-binding protein 12 (FK506BP), is a receptor protein for the immunosuppressive drug FK506 by the FK506BP/FK506 complex. However, the precise function of FK506BP in inflammatory diseases remains unclear. Therefore, we examined the protective effects of FK506BP on atopic dermatitis (AD) in tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-induced HaCaT cells and 2,4-dinitrofluorobenzene-induced AD-like dermatitis in Nishiki-nezumi Cinnamon/Nagoya (NC/Nga) mice using a cell-permeable PEP-1-FK506BP. Transduced PEP-1-FK506BP significantly inhibited the expression of cytokines, as well as the activation of NF-κB and mitogen-activated protein kinase (MAPK) in TNF-α/IFN-γ-induced HaCaT cells. Furthermore, topical application of PEP-1-FK506BP to NC/Nga mice markedly inhibited AD-like dermatitis as determined by a histological examination and assessment of serum IgE levels, as well as cytokines and chemokines. These results indicate that PEP-1-FK506BP inhibits NF-κB and MAPK activation in cells and AD-like skin lesions by reducing the expression levels of cytokines and chemokines, thus suggesting that PEP-1-FK506BP may be a potential therapeutic agent for AD. 相似文献
995.
Impact of Atherosclerosis Detection by Carotid Ultrasound on Physician Behavior and Risk‐Factor Management in Asymptomatic Hypertensive Subjects 下载免费PDF全文
996.
The impact of Agent Orange on characteristics of coronary artery lesion and repeat revascularization
997.
998.
Thomas S. King Daniel Potter Inn Soo Kang Catherine Norris Eileen Chen Robert S. Schenken Martin A. Javors 《Brain research》1999,824(1)
Immortalized GT1–7 neurons were used to characterize the effect of muscimol, a GABAA receptor agonist, to enhance pulsatile gonadotropin-releasing hormone (GnRH) release. GT1–7 neurons were grown on Cytodex-3 beads and placed in special superfusion microchambers. The cells were superfused at a rate of 6.2 ml·h−1 with Media 199 (pH 7.35) using a commercially available perfusion system. After a pre-muscimol period of 120 min, the cells were exposed for 5 min to 0.35, 1, 5 or 10 μM muscimol or 5 μM muscimol+20 μM of the GABAA receptor antagonist, bicuculline. Following removal of the muscimol (and bicuculline, in the case of the latter experiment), the superfusion was continued for another 115 min. Sample fractions were collected at 5 min intervals throughout the perfusion. Basal GnRH release from the GT1–7 neurons was pulsatile with an average interpulse interval of 45.4±0.5 min and an average pulse amplitude of 191.5±22.6 pg·min·ml−1. Our results also demonstrated that the GABAA receptor agonist, muscimol, enhances pulsatile GnRH release from GT1–7 neurons in culture. The response to muscimol was saturable and concentration-dependent with an EC50 of 0.47 μM. The effects of 5 μM muscimol to increase GnRH pulsatility were blocked by co-exposure to the GABAA receptor antagonist, bicuculline. The average GnRH interpulse intervals were 41.7±1.8 min, 32.5±2.9 min, 30.6±0.7 min and 25.5±0.4 min in the period following exposure to 0.35, 1, 5 and 10 μM of muscimol, respectively (post-muscimol period). GnRH pulse amplitude (mean-area for each pulse) was increased during exposure to muscimol but not during the pre- or post-muscimol periods. The GABAA receptor antagonist, bicuculline, itself had no effect on pulsatile GnRH release. These results are consistent with previously published reports suggesting that activation of the GABAA receptor stimulates hypothalamic GnRH release in embryonic and neonatal animals. 相似文献
999.
目的:探讨垂体脓肿的临床特征和治疗。方法:回顾性分析14例垂体脓肿患者的临床表现、影像学特征、诊断和治疗,并结合文献进行分析。结果:14例患者中头痛13例,垂体功能低下6例,视力视野影响6例,多饮多尿3例,发热3例。MRI增强病灶均呈环状强化。11例经蝶手术治疗,3例经开颅手术。术后随访头痛缓解者10例,视力、视野改善者4例,尿崩者2例恢复正常,垂体功能低下者中4例恢复正常,3例开颅手术者中2例复发,再经蝶手术治愈。结论:应用常规CT和MR术前诊断垂体脓肿困难,对鞍区囊性病变应考虑到垂体脓肿的可能。及早手术、正确选择手术入路、围手术期合理应用抗生素和适当的对症治疗是治疗垂体脓肿的关键。 相似文献
1000.
目的 研究脑梗死后遗症大鼠模型脑组织ATP、ADP及单胺类神经递质含量的变化。方法 建立脑梗死后遗症大鼠模型,用高效液相色谱(HPLC)法测定大鼠脑组织ATP、ADP及单胺类神经递质含量。结果 刺激组(SG)毛发相对黯淡无光、卷曲,精神萎靡,惊恐,消瘦,肢体无力,摄食减少,饮水减少,手术伤口愈合迟缓,符合中医脑梗死后遗症征候。正常组(NG)大鼠脑组织ATP、ADP含量显著高于SG组、术后不刺激组(SG)(P〈0.01),同时NSG组大鼠脑组织ATP、ADP含量显著高于SG组(P〈0.05)。SG组大鼠脑组织NE、DA和5-HT含量显著低于NG组(P〈0.01),NSG组(P〈0.05);NSG组大鼠脑组织DA含量显著低于NG组(P〈0.05)。结论 脑梗死后遗症大鼠由于能量代谢障碍而出现脑组织的ATP、ADP含量降低,并且伴有大脑释放单胺类递质增加及脑细胞内的单胺类递质含量减少,单胺类递质分泌增加又加重了脑组织的损伤,加剧ATP、ADP等能量物质代谢障碍,形成恶性循环。 相似文献