全文获取类型
收费全文 | 3204篇 |
免费 | 168篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 63篇 |
妇产科学 | 29篇 |
基础医学 | 428篇 |
口腔科学 | 46篇 |
临床医学 | 156篇 |
内科学 | 736篇 |
皮肤病学 | 57篇 |
神经病学 | 197篇 |
特种医学 | 115篇 |
外科学 | 634篇 |
综合类 | 9篇 |
预防医学 | 137篇 |
眼科学 | 12篇 |
药学 | 163篇 |
中国医学 | 5篇 |
肿瘤学 | 583篇 |
出版年
2023年 | 14篇 |
2022年 | 22篇 |
2021年 | 48篇 |
2020年 | 37篇 |
2019年 | 50篇 |
2018年 | 42篇 |
2017年 | 34篇 |
2016年 | 63篇 |
2015年 | 59篇 |
2014年 | 76篇 |
2013年 | 79篇 |
2012年 | 132篇 |
2011年 | 171篇 |
2010年 | 80篇 |
2009年 | 69篇 |
2008年 | 140篇 |
2007年 | 155篇 |
2006年 | 144篇 |
2005年 | 151篇 |
2004年 | 164篇 |
2003年 | 146篇 |
2002年 | 123篇 |
2001年 | 142篇 |
2000年 | 128篇 |
1999年 | 143篇 |
1998年 | 57篇 |
1997年 | 39篇 |
1996年 | 42篇 |
1995年 | 28篇 |
1994年 | 34篇 |
1993年 | 30篇 |
1992年 | 78篇 |
1991年 | 94篇 |
1990年 | 91篇 |
1989年 | 59篇 |
1988年 | 66篇 |
1987年 | 68篇 |
1986年 | 50篇 |
1985年 | 50篇 |
1984年 | 37篇 |
1983年 | 21篇 |
1982年 | 18篇 |
1979年 | 19篇 |
1977年 | 9篇 |
1973年 | 6篇 |
1972年 | 10篇 |
1971年 | 7篇 |
1970年 | 7篇 |
1969年 | 9篇 |
1968年 | 8篇 |
排序方式: 共有3385条查询结果,搜索用时 11 毫秒
91.
92.
p53 point mutations in primary human gastric carcinomas 总被引:12,自引:0,他引:12
Hiroshi Yokozaki Hiroki Kuniyasu Yasuhiko Kitadai Kenji Nishimura Hiroko Todo Ayşe Ayhan Wataru Yasui Hisao Ito Eiichi Tahara 《Journal of cancer research and clinical oncology》1992,119(2):67-70
Summary p53 point mutations in primary gastric carcinomas were analyzed by performing cDNA deoxynucleotide sequencing of the gene. Out of 16,9 (56.3%) primary gastric carcinoma cases, including early cancer, showed one or more p53 point mutations in their open-reading frame, and 4 out of 9 cases had a p53 point mutation within highly conserved domains. The characteristics of the p53 mutation spectrum observed in primary tumors were (a) frequent mutation at an A:T pair (50%, 7 out of 14 mutations), (b) high transversion incidence (29%, 4 out of 14 mutations), (c) no transition at CpG, and (d) no G:C to T:A transversion. Our results suggest that p53 mutation is a common event in gastric carcinoma occurring from the early stage of progression with its specific mutation spectrum.Abbreviation PCR-SSCP
polymerase chain reaction single-strand conformation polymorphism 相似文献
93.
94.
Tetsuro Yasui Jinju Nishino Naoko Shoda Yasuhiko Koizumi Satoru Ohashi Yuho Kadono 《Modern rheumatology / the Japan Rheumatism Association》2016,26(1):36-39
Objectives. The aim of this study was to clarify the prevalence and the predictive factors for undergoing total knee arthroplasty (TKA) among patients with rheumatoid arthritis (RA).Methods. The data of 1,134 patients with RA who were enrolled in the Japanese nationwide cohort database NinJa in 2003 and consecutively followed up until 2009 were analyzed.Results. Seventy-six patients underwent TKA during the observation period. The yearly progression of the modified Health Assessment Questionnaire or mHAQ score from 2003 to 2004, but not the yearly progression of the Disease Activity Score in 28 Joints or DAS28 or patient visual analog scale (VAS) score, was significantly higher in the patients who underwent TKA than those who did not.Multivariate analysis showed that knee involvement in the disease, high Steinbrocker stage (III or IV), and high patient VAS score at the time of enrollment were powerful predictive factors, with hazard ratios of 4.01, 3.71, and 1.20, respectively.According to survival analysis with TKA as an endpoint, patients with knee involvement in the disease at the time of enrollment had a significantly worse 5-year survival rate than did those without knee involvement (83.5% vs. 97.0%, respectively).Conclusion. Several factors were elucidated as predictive factors for undergoing TKA among patients with RA. 相似文献
95.
Yoshimoto A Ichikawa Y Waseda Y Yasui M Fujimura M Hebisawa A Nakao S 《Internal medicine (Tokyo, Japan)》2004,43(10):982-985
A 57-year-old man consulted our hospital with a history of the gradual onset of dyspnea and a productive cough. Chest computed tomographic (CT) scans showed a nodular shadow in a cavity lesion, and reticulonodular, cystic, and ground-grass opacities in the bilateral lung fields with honeycombing. He was diagnosed as having pulmonary aspergilloma and idiopathic pulmonary fibrosis (IPF). As an outpatient, he suffered from dyspnea upon physical exertion with exacerbation of the high-resolution CT (HRCT) opacities. An inhalation provocation test for Aspergillosis fumigatus was positive and chronic hypersensitivity pneumonitis (CHP) caused by Aspergillus was finally diagnosed. Insidious CHP is sometimes misdiagnosed as IPF. The diagnosis of insidious CHP should be made on the basis of a detailed history, specific HRCT findings, and lymphocyte-dominant bronchoalveolar lavage fluid cell findings. 相似文献
96.
To evaluate the effects of lung volume changes on the body surface electrocardiogram, we performed body surface potential mapping (87 lead points) in 20 normal subjects (group N) and in 21 patients with chronic pulmonary emphysema (group CPE). P-wave, QRS, ST-segment, ST-T and QRST iso-integral maps were constructed. Group-mean maps and the mean value of the maximum (max) and the minimum (min) on each map were compared between group N and group CPE. In group CPE, the body surface distribution of the P, QRS, ST, ST-T and QRST time integrals were all positioned downwards compared with those of group N. In addition, we also detected an increase in the max of P and decreases in the min of P; max and min of QRS; and in max of ST-T and QRST integrals. It was suggested that these changes were caused by the downward shift and clockwise rotation of the heart, and also by the decreased electrical conductivity of the lungs. 相似文献
97.
Fumihiko Yasui Masayuki Sudoh Masaaki Arai Michinori Kohara 《Journal of medical virology》2013,85(2):241-249
The influence of the intracellular redox state on the hepatitis C virus (HCV) life cycle is poorly understood. This study demonstrated the anti‐HCV activity of 2,3‐dihydro‐5‐hydroxy‐2,2‐dipentyl‐4,6‐di‐tert‐butylbenzofuran (BO‐653), a synthetic lipophilic antioxidant, and examined whether BO‐653's antioxidant activity is integral to its anti‐HCV activity. The anti‐HCV activity of BO‐653 was investigated in HuH‐7 cells bearing an HCV subgenomic replicon (FLR3‐1 cells) and in HuH‐7 cells infected persistently with HCV (RMT‐tri cells). BO‐653 inhibition of HCV replication was also compared with that of several hydrophilic and lipophilic antioxidants. BO‐653 suppressed HCV replication in FLR3‐1 and RMT‐tri cells in a concentration‐dependent manner. The lipophilic antioxidants had stronger anti‐HCV activities than the hydrophilic antioxidants, and BO‐653 displayed the strongest anti‐HCV activity of all the antioxidants examined. Therefore, the anti‐HCV activity of BO‐653 was examined in chimeric mice harboring human hepatocytes infected with HCV. The combination treatment of BO‐653 and polyethylene glycol‐conjugated interferon‐α (PEG‐IFN) decreased serum HCV RNA titer more than that seen with PEG‐IFN alone. These findings suggest that both the lipophilic property and the antioxidant activity of BO‐653 play an important role in the inhibition of HCV replication. J. Med. Virol. 85:241–249, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
98.
Toshiro Kitagawa Takuya Hattori Kazuhiro Sentani Atsuhiro Senoo Yuto Fujii Shinya Takahashi Wataru Yasui Yukiko Nakano Yasuki Kihara 《Journal of Cardiovascular Computed Tomography》2021,15(2):175-179
BackgroundAnti-inflammatory therapy targeting interleukin (IL)-1β reduced cardiovascular events in a randomized trial. We evaluated the relationship between IL-1β mRNA expression in epicardial adipose tissue (EAT) and clinically-assessed coronary atherosclerosis on computed tomography (CT).MethodsWe studied 45 patients before cardiac surgery (coronary artery bypass grafting [CABG], n ?= ?18; non-CABG, n ?= ?27). EAT volume, the coronary calcium score (CCS), and the presence of non- and/or partially-calcified coronary plaques (NCPs) and high-risk coronary plaques (HRPs; minimum CT density <30 Hounsfield units and vascular remodeling index >1.1) on CT angiography were assessed. EAT samples were obtained during cardiac surgery. IL-1β mRNA expression in EAT was measured using quantitative real-time PCR and normalized to that of β-actin in each patient.ResultsThere was no difference in IL-1β mRNA levels between patients who were scheduled for CABG and non-CABG surgery or among subgroups based on the CCS. However, patients with NCPs (median [interquartile range], 4.1[2.0-11.6]E-4 versus 1.8[0.6-4.5]E-4, p ?= ?0.024) and HRP (7.6[3.0-20.4]E-4 versus 1.9[0.7-4.3]E-4, p ?= ?0.0023) had higher IL-1β mRNA levels than those without these plaques. On multivariate analysis adjusted for age, sex, coronary risk factors, statin therapy, CCS, and EAT volume, the presence of HRPs was significantly correlated with elevated IL-1β mRNA levels in EAT (β ?= ?0.39, p ?= ?0.047).ConclusionOur data suggest a contribution of EAT to coronary atherosclerosis through molecular behavior, such as IL-1β gene expression, which may be a new therapeutic target. 相似文献
99.
Simon Chau Atsushi Fujii Yingqi Wang Arno Vandebroek Wakami Goda Masato Yasui Yoichiro Abe 《Genes to cells : devoted to molecular & cellular mechanisms》2021,26(3):152-164
Aquaporin-4 is a transmembrane water channel protein, the C-terminal domain of which is facing the cytosol. In the process of investigating the role of the C-terminal domain of aquaporin-4 with regard to intracellular trafficking, we observed that a derivative of aquaporin-4, in which the C-terminal 53 amino acids had been removed (Δ271-323), was localized to intracellular compartments, including the endoplasmic reticulum, but was not expressed on the plasma membranes. This was determined by immunofluorescence staining and labeling of the cells with monoclonal antibody specifically recognizing the extracellular domain of aquaporin-4, followed by confocal microscopy and flow cytometry. Deletion of additional amino acids in the C-terminal domain of aquaporin-4 led to its redistribution to the plasma membrane. This suggests that the effect of the 53-amino acid deletion on the subcellular localization of aquaporin-4 could be attributed to the formation of a signal at the C terminus that retained aquaporin-4 in intracellular compartments, rather than the loss of a signal required for plasma membrane targeting. Substitution of the lysine at position 268 with alanine could rescue the Δ271-323-associated retention in the cytosol, suggesting that the C-terminal sequence of the mutant served as a signal similar to a di-lysine motif. 相似文献
100.
OBJECTIVE: Heart failure in patients and in animal models is associated with action potential prolongation of the ventricular myocytes. Changes in several membrane currents have been already demonstrated to underlie this prolongation. However, information on the two components (I(Kr) and I(Ks)) of the delayed rectifier potassium current (I(K)) in rapid pacing induced heart failure is lacking. METHODS AND RESULTS: Action potentials and whole-cell currents, I(K), I(to1), I(K1), and I(Ca-L) were recorded in apical myocytes of left ventricle from 10 rabbits subjected to left ventricular pacing at 350-380 beats/min for 3-4 weeks and 10 controls with sham operation. Action potential duration at 90% repolarization (APD(90)) was prolonged in myocytes from failing hearts compared to controls at both cycle lengths of 333 and 1000 ms. Both E-4031-sensitive and -resistant components of I(K) (I(Kr), I(Ks)) in myocytes from failing hearts were significantly less than those of control hearts; tail current densities of I(Kr) and I(Ks) following depolarization to +50 mV were 0.62+/-0.05 vs. 0.96+/-0.12 pA/pF (P<0.05), and 0.27+/-0.08 vs. 0.52+/-0.08 pA/pF (P<0.05), respectively. There was no significant difference between control and failing myocytes in the voltage- and time-dependence of activation of total I(K), I(Kr) and I(Ks). The peak of L-type Ca(2+) current (I(Ca-L)) was significantly reduced in myocytes from failing hearts (at +10 mV, -9.29+/-0.52 vs. -12.28+/-1.63 pA/pF, P<0.05), as was the Ca(2+)-independent transient outward current (I(to1); at +40 mV, 4.8+/-0.9 vs. 9.6+/-1.3 pA/pF, P<0.05). Steady state I-V curve for I(K1) was similar in myocytes from failing and control hearts. CONCLUSIONS: Decrease of I(K) (both I(Kr) and I(Ks)) in addition to reduced I(to1), may underly action potential prolongation at physiological cycle length and thereby contribute to arrhythmogenesis in heart failure. 相似文献