全文获取类型
收费全文 | 5066篇 |
免费 | 333篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 132篇 |
妇产科学 | 67篇 |
基础医学 | 787篇 |
口腔科学 | 83篇 |
临床医学 | 354篇 |
内科学 | 1359篇 |
皮肤病学 | 257篇 |
神经病学 | 329篇 |
特种医学 | 129篇 |
外科学 | 456篇 |
综合类 | 17篇 |
一般理论 | 2篇 |
预防医学 | 255篇 |
眼科学 | 151篇 |
药学 | 409篇 |
中国医学 | 14篇 |
肿瘤学 | 587篇 |
出版年
2024年 | 4篇 |
2023年 | 26篇 |
2022年 | 75篇 |
2021年 | 158篇 |
2020年 | 105篇 |
2019年 | 100篇 |
2018年 | 167篇 |
2017年 | 124篇 |
2016年 | 150篇 |
2015年 | 119篇 |
2014年 | 169篇 |
2013年 | 251篇 |
2012年 | 355篇 |
2011年 | 373篇 |
2010年 | 208篇 |
2009年 | 203篇 |
2008年 | 357篇 |
2007年 | 367篇 |
2006年 | 346篇 |
2005年 | 319篇 |
2004年 | 323篇 |
2003年 | 290篇 |
2002年 | 284篇 |
2001年 | 47篇 |
2000年 | 40篇 |
1999年 | 47篇 |
1998年 | 55篇 |
1997年 | 51篇 |
1996年 | 32篇 |
1995年 | 26篇 |
1994年 | 20篇 |
1993年 | 27篇 |
1992年 | 22篇 |
1991年 | 14篇 |
1990年 | 13篇 |
1989年 | 24篇 |
1988年 | 14篇 |
1987年 | 12篇 |
1986年 | 8篇 |
1985年 | 11篇 |
1984年 | 12篇 |
1983年 | 7篇 |
1982年 | 9篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 10篇 |
1978年 | 4篇 |
1973年 | 15篇 |
1972年 | 4篇 |
1968年 | 4篇 |
排序方式: 共有5425条查询结果,搜索用时 15 毫秒
61.
In this cross-sectional study, the relationships of the physiological levels of estradiol (E2) and dehydroepiandrosterone-sulfate (DHEA-S) to the lipid and lipoprotein profiles were investigated in 212 apparently healthy men aged from 18 to 59 years old. These subjects were divided into tertiles according to the levels of E2 and DHEA-S, respectively. We performed one-way analysis of variance and analysis of co-variance controlling for age, body mass index, percent body fat, waist to hip ratio, maximal oxygen uptake, alcohol and cigarette consumptions as confounding factors.A lower E2 level was associated with higher concentrations of total cholesterol (TC) and low density lipoprotein cholesterol. A lower DHEA-S level was associated with a lower concentration of high density lipoprotein cholesterol (HDLC) and a higher ratio of TC / HDLC. These correlations remained significant after adjusting for the above confounding factors. Neither free testosterone nor sex hormone-binding globulin was associated with the lipids and lipoproteins. These results suggest that higher levels of E2 and DHEA-S, at least in physiological concentrations, are related to the favorable lipid and lipoprotein levels in men. 相似文献
62.
In vitro drug-drug interactions with perospirone and concomitantly administered drugs in human liver microsomes. 总被引:3,自引:0,他引:3
Jin Shimakura Naoko Tani Yoshiko Mizuno Setsuko Komuro Hiroshi Kanamaru 《European journal of drug metabolism and pharmacokinetics》2003,28(1):67-72
In vitro metabolism studies were conducted to assess drug-drug interactions between perospirone, an antipsychotic agent, and concomitantly administered drugs--biperiden, flunitrazepam, haloperidol, and diazepam--using human liver microsomes. The metabolism of perospirone in the presence of 100 microg/ml drugs was decreased to 45-73% of that in their absence, whereas no effects were observed with any of the drugs at 1 microg/ml or lower. The effects of perospirone on the metabolism of concomitantly administered drugs were also assessed, and no inhibitory effect was observed. Thus, the metabolism of perospirone and concomitantly administered drugs did not demonstrate any marked mutual inhibition in the human liver microsomes. On the other hand, the perospirone metabolism was markedly reduced by ketoconazole indicating a major role for CYP 3A4. Based on the inhibition constant (Ki) for perospirone metabolism and the plasma unbound concentration of ketoconazole, in vivo perospirone clearance was estimated to be reduced to 64-90% of the control level. Thus careful attention should be paid to the possibility of increase in unchanged perospirone concentration when perospirone is co-administered with drugs that are known as CYP3A4 inhibitors, including macrolide antibiotics and other imidazole antifungals. 相似文献
63.
Taro Semba Yasuhiro Funahashi Naoto Ono Yuji Yamamoto Naoko Hata Sugi Makoto Asada Kentaro Yoshimatsu Toshiaki Wakabayashi 《Clinical cancer research》2004,10(4):1430-1438
We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin alpha2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin alpha2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin alpha2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin alpha2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin alpha2 on platelets might serve as a biological marker for the antitumor efficacy of E7820. 相似文献
64.
Minoru Hojo Naoko Momotani Noriko Ikeda Akihiko Ueda Kuniko Uno Takashi Ishikita Akira Ishiguro Toshikazu Shimbo 《Pediatrics international》1998,40(5):483-485
Abstract We report here a case of neonatal hyperthyroidism born to a mother, whose pregnancy was complicated by poorly controlled Graves' disease. The patient demonstrated exophthalmos and marked goiter at birth, indicating the existence of thyrotoxicosis in utero. The mother's Graves' disease was well controlled in the third trimester, resulting in a slightly lower level of free thyroxine (FT4 ) in the umbilical cord blood serum; however, thyroid-stimulating hormone (TSH) was undetectable. Thyroid-stimulating hormone remained undetectable for 2 months, while FT4 levels varied in the course. This case suggests that severe and prolonged thyrotoxicosis in utero, due to poor control of pregnancy with Graves' disease, might induce unresponsiveness of the hypothalamo-pituitary system in the newborn. 相似文献
65.
Shin-ichi Fukumoto Naoko Yamauchi Hisashi Moriguchi Yoshitaka Hippo Akira Watanabe Junji Shibahara Hirokazu Taniguchi Shumpei Ishikawa Hirotaka Ito Shogo Yamamoto Hiroko Iwanari Mitsugu Hironaka Yuichi Ishikawa Toshiro Niki Yasunori Sohara Tatsuhiko Kodama Masaharu Nishimura Masashi Fukayama Hirotoshi Dosaka-Akita Hiroyuki Aburatani 《Clinical cancer research》2005,11(5):1776-1785
PURPOSE: Squamous cell carcinoma (SCC) and adenocarcinoma of the lung are currently subject to similar treatment regimens despite distinct differences in histology and epidemiology. The aim of this study is to identify a molecular target with diagnostic and therapeutic values for SCC. EXPERIMENTAL DESIGN: Genes specifically up-regulated in SCC were explored through microarray analysis of 5 SCCs, 5 adenocarcinomas, 10 small cell lung carcinomas, 27 normal tissues, and 40 cancer cell lines. Clinical usefulness of these genes was subsequently examined mainly by immunohistochemical analysis. RESULTS: Seven genes, including aldo-keto reductase family 1, member B10 (AKR1B10), were identified as SCC-specific genes. AKR1B10 was further examined by immunohistochemical analysis of 101 non-small cell lung carcinomas (NSCLC) and its overexpression was observed in 27 of 32 (84.4%) SCCs and 19 of 65 (29.2%) adenocarcinomas. Multiple regression analysis showed that smoking was an independent variable responsible for AKR1B10 overexpression in NSCLCs (P < 0.01) and adenocarcinomas (P < 0.01). AKR1B10 staining was occasionally observed even in squamous metaplasia, a precancerous lesion of SCC. CONCLUSION: AKR1B10 was overexpressed in most cases with SCC, which is closely associated with smoking, and many adenocarcinoma cases of smokers. These results suggest that AKR1B10 is a potential diagnostic marker specific to smokers' NSCLCs and might be involved in tobacco-related carcinogenesis. 相似文献
66.
67.
68.
Joseph H. Liao MD Hernan Jara PhD Rohini Nadgir MD Elliott Elias MD Nekou Nowrouzi Naoko Saito MD Martin H. Steinberg MD Osamu Sakai MD PhD 《Journal of magnetic resonance imaging : JMRI》2013,37(5):1182-1188
Purpose:
To identify and characterize sickle cell disease (SCD)‐related changes in the composition of mandibular bone marrow using qMRI relaxometry histograms.Materials and Methods:
Thirteen SCD patients and 17 controls underwent brain MR imaging with the mixed turbo spin‐echo (TSE) pulse sequence at 1.5T. The mandible was manually segmented and divided into body, angle, ramus, and condyle. T1 and T2 histograms of each mandible were modeled with Gaussian functions. The relaxation time histogram peaks were calculated, and the number of monomodal versus bimodal curves was compared.Results:
SCD patients exhibited monomodal distributions on both T1 and T2 histograms, consistent with a composition of predominantly red hematopoietic marrow. Eighty‐eight percent of mandibles in control subjects exhibited a bimodal distribution in T1 and all showed a bimodal distribution in T2, indicating mixed but predominantly yellow marrow composition. The second peak in control subjects was shorter in T1 and longer in T2, consistent with yellow marrow composition.Conclusion:
Instead of physiological fatty replacement, SCD patients exhibit red marrow persistence in the mandible, likely due to the increased demand for hematopoiesis. This phenomenon can be manifested by a monomodal curve in both T1 and T2 relaxometric histograms. J. Magn. Reson. Imaging 2013;37:1182–1188. © 2012 Wiley Periodicals, Inc. 相似文献69.
Tetsushi Iida Naoko Iida Jun Sese Takehiko Kobayashi 《Genes to cells : devoted to molecular & cellular mechanisms》2021,26(8):555-569
Ribonucleotides incorporated in the genome are a source of endogenous DNA damage and also serve as signals for repair. Although recent advances of ribonucleotide detection by sequencing, the balance between incorporation and repair of ribonucleotides has not been elucidated. Here, we describe a competitive sequencing method, Ribonucleotide Scanning Quantification sequencing (RiSQ-seq), which enables absolute quantification of misincorporated ribonucleotides throughout the genome by background normalization and standard adjustment within a single sample. RiSQ-seq analysis of cells harboring wild-type DNA polymerases revealed that ribonucleotides were incorporated nonuniformly in the genome with a 3′-shifted distribution and preference for GC sequences. Although ribonucleotide profiles in wild-type and repair-deficient mutant strains showed a similar pattern, direct comparison of distinct ribonucleotide levels in the strains by RiSQ-seq enabled evaluation of ribonucleotide excision repair activity at base resolution and revealed the strand bias of repair. The distinct preferences of ribonucleotide incorporation and repair create vulnerable regions associated with indel hotspots, suggesting that repair at sites of ribonucleotide misincorporation serves to maintain genome integrity and that RiSQ-seq can provide an estimate of indel risk. 相似文献
70.