全文获取类型
收费全文 | 3197篇 |
免费 | 153篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 30篇 |
妇产科学 | 28篇 |
基础医学 | 415篇 |
口腔科学 | 47篇 |
临床医学 | 185篇 |
内科学 | 898篇 |
皮肤病学 | 39篇 |
神经病学 | 223篇 |
特种医学 | 84篇 |
外科学 | 517篇 |
综合类 | 10篇 |
预防医学 | 118篇 |
眼科学 | 27篇 |
药学 | 156篇 |
中国医学 | 2篇 |
肿瘤学 | 510篇 |
出版年
2023年 | 18篇 |
2022年 | 36篇 |
2021年 | 67篇 |
2020年 | 42篇 |
2019年 | 27篇 |
2018年 | 47篇 |
2017年 | 40篇 |
2016年 | 66篇 |
2015年 | 49篇 |
2014年 | 51篇 |
2013年 | 71篇 |
2012年 | 140篇 |
2011年 | 154篇 |
2010年 | 84篇 |
2009年 | 69篇 |
2008年 | 146篇 |
2007年 | 142篇 |
2006年 | 163篇 |
2005年 | 157篇 |
2004年 | 149篇 |
2003年 | 126篇 |
2002年 | 87篇 |
2001年 | 116篇 |
2000年 | 101篇 |
1999年 | 89篇 |
1998年 | 49篇 |
1997年 | 26篇 |
1996年 | 24篇 |
1995年 | 18篇 |
1993年 | 17篇 |
1992年 | 67篇 |
1991年 | 70篇 |
1990年 | 68篇 |
1989年 | 65篇 |
1988年 | 70篇 |
1987年 | 68篇 |
1986年 | 71篇 |
1985年 | 83篇 |
1984年 | 48篇 |
1983年 | 38篇 |
1982年 | 19篇 |
1979年 | 24篇 |
1978年 | 19篇 |
1977年 | 22篇 |
1975年 | 19篇 |
1973年 | 19篇 |
1971年 | 17篇 |
1969年 | 24篇 |
1968年 | 34篇 |
1967年 | 20篇 |
排序方式: 共有3367条查询结果,搜索用时 406 毫秒
61.
Miyoshi Jun Ozaki Ryo Yonezawa Hiromi Mori Hideaki Kawamura Naohiro Matsuura Minoru Hisamatsu Tadakazu 《Journal of gastroenterology》2022,57(2):82-89
Journal of Gastroenterology - The development of feasible, reliable parameters and criteria for intestinal ultrasound (IUS) to estimate endoscopic remission of ulcerative colitis (UC) is a crucial... 相似文献
62.
Ogawa M Miyoshi K Morito N Kodama S Yahiro E Fujimi K Ohta T Mihara H Yamanouchi Y Urata H Hiroki T Saku K 《International journal of cardiology》2004,93(2-3):343-346
Left ventricular (LV) aneurysm has been recognized to frequently become a substrate of ventricular tachyarrhythmias. We report a case of a 66-year-old woman with symptomatic sustained monomorphic ventricular tachycardia (SMVT) originating from saccular apical LV aneurysm without definite underlying diseases. We performed catheter ablation using electroanatomical and conventional bipolar potential mapping. During SMVT, we found an area of fragmented potential -40 ms preceding the earliest wide QRS complex in the area of the apical LV aneurysm. Radiofrequency applications were delivered to this area. Since then, SMVT was no longer inducible by programmed electrical stimulation. The patient has remained free of VT recurrences during a subsequent 12-month follow-up period. 相似文献
63.
Ohno J Watanabe E Toyama J Kawamura T Ohno M Kodama I 《International journal of cardiology》2004,93(2-3):263-268
BACKGROUND: Recent clinical trials suggest that the mortality in high-risk patients with ischemic heart disease can be significantly reduced with the use of implantable cardioverter-defibrillator (ICD). Given the high cost and invasiveness of the procedure, it is important to apply it to the patients after myocardial infarction (MI) highly susceptible to sudden arrhythmic death. OBJECTIVE: The purpose of this study was to assess clinical predictors of mortality in post-MI patients in Japan. METHODS AND RESULTS: In 495 consecutive MI survivors, 350 (71%) received acute-reperfusion therapy, whereas 145 (29%) did not. Nonsustained ventricular tachycardia (NSVT) was present in 136 patients (28%) in 24-h ambulatory ECGs at 7+/-6 in-hospital days. Left ventricular dysfunction (LVEF< or =35%) was present in 20/347 patients (5.7%) at 13+/-8 days. Forty-eight patients (9.7%) died during the follow-up period (48+/-13 months); 23 from cardiac and 25 from noncardiac causes. Kaplan-Meier survival analyses showed that mortality rates were higher among patients who were > or =70 years old (log-rank test, P<0.0001); had heart failure at admission (Killip scale> or =2, P=0.001); did not receive acute-reperfusion (P=0.004); and had left ventricular dysfunction with LVEF< or =35% (P=0.02). The presence of NSVT was a significant predictor of death (P=0.036) only in the patients who did not receive acute-reperfusion. Multivariate Cox regression analysis revealed that an independent predictor of total mortality was an age> or =70 (odds ratio, 1.06; 95% confidence interval, 1.01-1.11; P<0.00001). CONCLUSIONS: High-risk patients after acute MI can be identified on the basis of age, ventricular dysfunction, heart failure and acute-reperfusion therapy. The presence of NSVT before discharge has a prognostic value only in the patients without acute-reperfusion. 相似文献
64.
We introduced a self-inactivation (SIN) lentivirus vector (LV) into Xenopus laevis cell lines and established a permanent cell line expressing a reporter gene in a 3,5,3'-l-triiodothyronine (T(3)) dependent manner. The SIN LV contained the luciferase gene downstream from the X. laevis T(3)-response elements (TREs) and the SV40 promoter, and the enhanced green fluorescent protein (EGFP) gene downstream from the cytomegalovirus (CMV) promoter. It was integrated into the genome of X. laevis XL58, XTC2, and KR cells. The SIN LV transduced the X. laevis cells as efficiently as mammalian cells; however, the expression of EGFP in the transgene decreased with increasing culture time. A cell clone exhibiting the highest TH-dependent luciferase gene expression (XL58-TRE-Luc clone) was isolated from the EGFP-positive XL58 cell pool and characterized. The minimum effective concentration of T(3) that significantly induced the luciferase gene expression was 10(-11)M in the XL58-TRE-Luc clone. The application of the luciferase gene assay using the permanent XL58-TRE-Luc clone for the screening of thyroid-disrupting chemicals revealed that tetrachlorobisphenol A, at 10(-6)M, had a weak T(3)-agonist activity, whereas trichlorobisphenol A, at 10(-8) - 10(-6)M had a weak T(3)-antagonist activity. Our results indicated that the permanent X. laevis cell line containing a T(3)-response transgene could be used as a bioassay, with small intra-assay variation, for the rapid screening, identification, and characterization of the thyroid-disrupting chemicals. 相似文献
65.
Takeuchi S; Bartram CR; Miller CW; Reiter A; Seriu T; Zimmerann M; Schrappe M; Mori N; Slater J; Miyoshi I; Koeffler HP 《Blood》1996,87(8):3368-3374
Cytogenetic analysis of acute lymphoblastic leukemia (ALL) of childhood identified nonrandom chromosomal abnormalities of the short arm of chromosome 12. The alterations include deletions that are thought to be indicative of the presence of a tumor suppressor gene that is mutated on the remaining allele. To refine further the chromosomal localization of this gene, we analyzed the loss of heterozygosity (LOH) of chromosome 12 in 100 primary ALL samples using 22 polymorphic markers and identified two distinct smallest common deleted regions on chromosome 12p13. One region is flanked by D12S77 and D12S98 and has a size of 4 cM. Twenty-six percent of informative patients showed LOH in this region. This region may contain the TEL gene. The other region is flanked by D12S269 and D12S308 including the KIP1 gene. Forty-four percent of informative patients showed LOH in this second region. Mutational analysis of KIP1 using polymerase chain reaction-single- strand conformation polymorphism analysis and Southern blot analysis showed no homozygous deletions and point mutations suggesting that the altered gene in this second region is not the KIP1. Clinical data showed that LOH of 12p was demonstrated more frequently in precursor-B ALLs (32 of 80; 40%) than in T-ALLs (1 of 20; 5%) (P = .0027). Furthermore, patients with 12p LOH were younger (P = .013), with a lower DNA index (P = .046), but they had the same survival rates at 3 years. In summary, these data suggest that two different tumor suppressor genes are on chromosome arm 12p, which act separately in the development of childhood precursor-B ALLs. One of the tumor suppressor genes is in the region the KIP1 gene, but our data suggest this gene is not abnormal. The other target is in the region of the TEL gene; and this candidate deserves further study. 相似文献
66.
Yamashita K Miyoshi T Arai T Endo N Itoh H Makino K Mizugishi K Uchiyama T Sasada M 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(44):16912-16917
Reactive oxygen species produced by phagocytosing neutrophils are essential for innate host defense against invading microbes. Previous observations revealed that antibody-catalyzed ozone formation by human neutrophils contributed to the killing of bacteria. In this study, we discovered that 4 amino acids themselves were able to catalyze the production of an oxidant with the chemical signature of ozone from singlet oxygen in the water-oxidation pathway, at comparable level to antibodies. The resultant oxidant with the chemical signature of ozone exhibited significant bactericidal activity in our distinct cell-free system and in human neutrophils. The results also suggest that an oxidant with the chemical signature of ozone produced by neutrophils might potentiate a host defense system, when the host is challenged by high doses of infectious agents. Our findings provide biological insights into the killing of bacteria by neutrophils. 相似文献
67.
68.
Kanako Iwasaki Tomoyuki Fujiyama Shinya Nakata Minjeong Park Chika Miyoshi Noriko Hotta-Hirashima Aya Ikkyu Miyo Kakizaki Fumihiro Sugiyama Seiya Mizuno Manabu Abe Kenji Sakimura Satoru Takahashi Hiromasa Funato Masashi Yanagisawa 《The Journal of neuroscience》2021,41(12):2733
Sleep is regulated in a homeostatic manner. Sleep deprivation increases sleep need, which is compensated mainly by increased EEG δ power during non-rapid eye movement sleep (NREMS) and, to a lesser extent, by increased sleep amount. Although genetic factors determine the constitutive level of sleep need and sleep amount in mice and humans, the molecular entity behind sleep need remains unknown. Recently, we found that a gain-of-function Sleepy (Slp) mutation in the salt-inducible kinase 3 (Sik3) gene, which produces the mutant SIK3(SLP) protein, leads to an increase in NREMS EEG δ power and sleep amount. Since Sik3Slp mice express SIK3(SLP) in various types of cells in the brain as well as multiple peripheral tissues from the embryonic stage, the cell type and developmental stage responsible for the sleep phenotype in Sik3Slp mice remain to be elucidated. Here, we generated two mouse lines, synapsin1CreERT2 and Sik3ex13flox mice, which enable inducible Cre-mediated, conditional expression of SIK3(SLP) in neurons on tamoxifen administration. Administration of tamoxifen to synapsin1CreERT2 mice during late infancy resulted in higher recombination efficiency than administration during adolescence. SIK3(SLP) expression after late infancy increased NREMS and NREMS δ power in male synapsin1CreERT2; Sik3ex13flox/+ mice. The expression of SIK3(SLP) after adolescence led to a higher NREMS δ power without a significant change in NREMS amounts. Thus, neuron-specific expression of SIK3(SLP) after late infancy is sufficient to increase sleep.SIGNIFICANCE STATEMENT The propensity to accumulate sleep need during wakefulness and to dissipate it during sleep underlies the homeostatic regulation of sleep. However, little is known about the developmental stage and cell types involved in determining the homeostatic regulation of sleep. Here, we show that Sik3Slp allele induction in mature neurons in late infancy is sufficient to increase non-rapid eye movement sleep amount and non-rapid eye movement sleep δ power. SIK3 signaling in neurons constitutes an intracellular mechanism to increase sleep. 相似文献
69.
Masahiro Miyoshi Rika Komagome Setsuko Ishida Hideki Nagano Kenichi Takahashi Motohiko Okano 《Archives of virology》2013,158(4):775-784
We determined four complete nucleotide sequences of echovirus 6 (E6) isolated from an epidemic of aseptic meningitis (AM) in Hokkaido, Japan, in 2011. Phylogenetic analysis of the genes encoding viral capsid protein 1 revealed that the strains were closely related to E6 strains isolated in China in recent years, but they were distantly related to E6 strains isolated from patients with AM in Osaka Prefecture, Japan, in 2011. The genes encoding the viral protease and RNA-dependent RNA polymerase (3CD) were closely related to those of several non-E6 strains of the species Human enterovirus B isolated in China, South Korea, and Australia from 1999 to 2010, resulting in a novel cluster in the phylogenetic tree. These results suggest that the incidence of AM in Japan in 2011 was caused by at least two lineages of E6 strains, and a lineage of the 3CD gene was interspersed among different serotypic strains isolated in Western Pacific countries. 相似文献
70.
Yukari Okita Ling Zheng Kunio Kawanishi Hirotoshi Miyoshi Kazuyoshi Yanagihara Mitsuyasu Kato 《Genes to cells : devoted to molecular & cellular mechanisms》2021,26(5):336-343
Three-dimensional (3D) culturing mimics the heterogeneous cellular conditions of the in vivo tumor microenvironment compared to 2D monolayer-cultured cells and 3D cultures of established cancer cell lines (sphere culture) or patient-derived cancer cells (organoid culture) are frequently used for cancer research or drug screening and evaluation. To establish more cost and time-efficient 3D culture methods for cancer cell lines, we supplemented sphere culture medium with polyvinyl alcohol (PVA) and found that 3D sphere cultures of breast and pancreatic cancer cell lines were significantly increased. Mechanistically, we found that PVA prevented cell death and promoted cellular proliferation while maintaining levels of stemness-related gene expression. Furthermore, we showed that polyvinyl formal resin (PVF) 3D scaffolds made by cross-linked PVA can function in serum-free, long-term 3D cultures to support maintenance of sphere- or tumor-like cell masses for diverse cancer cell types. Taken together, we demonstrate the effectiveness of PVA and PVF in human cancer cell line culture protocols. 相似文献