全文获取类型
收费全文 | 3032篇 |
免费 | 211篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 45篇 |
妇产科学 | 38篇 |
基础医学 | 426篇 |
口腔科学 | 100篇 |
临床医学 | 244篇 |
内科学 | 792篇 |
皮肤病学 | 186篇 |
神经病学 | 209篇 |
特种医学 | 84篇 |
外科学 | 447篇 |
综合类 | 16篇 |
预防医学 | 96篇 |
眼科学 | 41篇 |
药学 | 233篇 |
中国医学 | 15篇 |
肿瘤学 | 263篇 |
出版年
2023年 | 19篇 |
2022年 | 24篇 |
2021年 | 66篇 |
2020年 | 52篇 |
2019年 | 68篇 |
2018年 | 77篇 |
2017年 | 59篇 |
2016年 | 45篇 |
2015年 | 73篇 |
2014年 | 84篇 |
2013年 | 113篇 |
2012年 | 177篇 |
2011年 | 185篇 |
2010年 | 75篇 |
2009年 | 90篇 |
2008年 | 143篇 |
2007年 | 130篇 |
2006年 | 154篇 |
2005年 | 158篇 |
2004年 | 169篇 |
2003年 | 135篇 |
2002年 | 136篇 |
2001年 | 62篇 |
2000年 | 81篇 |
1999年 | 73篇 |
1998年 | 51篇 |
1997年 | 41篇 |
1996年 | 30篇 |
1995年 | 28篇 |
1994年 | 23篇 |
1993年 | 27篇 |
1992年 | 64篇 |
1991年 | 46篇 |
1990年 | 53篇 |
1989年 | 50篇 |
1988年 | 37篇 |
1987年 | 43篇 |
1986年 | 38篇 |
1985年 | 43篇 |
1984年 | 29篇 |
1983年 | 20篇 |
1982年 | 13篇 |
1981年 | 13篇 |
1979年 | 19篇 |
1978年 | 17篇 |
1977年 | 12篇 |
1974年 | 9篇 |
1973年 | 12篇 |
1971年 | 16篇 |
1970年 | 19篇 |
排序方式: 共有3255条查询结果,搜索用时 781 毫秒
1.
2.
Rebecca L. King Albert C. Yan Debora R. Sekiguchi John K. Choi 《Journal of cutaneous pathology》2015,42(12):1012-1017
Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin. 相似文献
3.
High incidence of nitrosamine-induced tumorigenesis in mice lacking DNA repair methyltransferase 总被引:12,自引:4,他引:8
Iwakuma T; Sakumi K; Nakatsuru Y; Kawate H; Igarashi H; Shiraishi A; Tsuzuki T; Ishikawa T; Sekiguchi M 《Carcinogenesis》1997,18(8):1631-1635
The enzyme O6-methylguanine-DNA methyltransferase repairs alkylation-
induced DNA damage, O6-methylguanine and O4-methylthymine, the former being
formed more frequently. Previously, by means of gene targeting, we
generated mice in which alleles for methyltransferase were disrupted. We
now use these mouse lines, which are totally deficient in methyltransferase
activity, to examine protective effects of the enzyme against tumor
formation. In gene-targeted female mice given an i.p. injection of 5 mg/kg
of dimethylnitrosamine, a larger number of liver and lung tumors occurred,
as compared with normal female mice treated in the same manner. In male
mice given a lower dose of carcinogen, the difference between normal and
gene-targeted mice was statistically insignificant although more tumors did
form in the gene-targeted mice. Methyltransferase apparently afforded
protection from nitrosamine- induced tumorigenesis.
相似文献
4.
5.
6.
Yasuhiro Sano Shigeharu Yamashiro Asuka Komano Hisashi Maruko Hiroshi Sekiguchi Yasuo Takayama Ryoji Sekioka Kouichiro Tsuge Isaac Ohsawa Mieko Kanamori-Kataoka Yasuo Seto Akiyoshi Satoh 《Forensic Toxicology》2007,25(2):76-79
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal
enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored
matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins
could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected
after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals
usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the
detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for
SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively.
The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations. 相似文献
7.
Hiroomi Murayama Masanobu Meda Ken Miyahara Yoshimasa Sakai Hajime Sakurai Hiroki Hasegawa Akemi Kawamura 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(3):91-97
Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery.
Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group
2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in
both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous
blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4
mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum
hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative
value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement
was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves,
and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing
important options in comprehensive blood conservation programs in current pediatric open-heart surgery. 相似文献
8.
9.
Ryoji Tsuboi Charles N Okeke Akemi Inoue Masashi Yamazaki Masataro Hiruma Hideoki Ogawa 《Nippon Ishinkin Gakkai Zasshi》2002,43(2):91-93
The diagnosis and choice of treatment for dermatophytoses are usually based on the result of microscopic observation of hyphal elements and culture. However, false negative cultures have sometimes been encountered and appropriate timing of discontinuation of treatment has not been formulated. In this study, we attempted the identification and viability assessment of dermatophytes based on the quantitative measurement of dermatophyte actin (ACT) mRNA. An internal fragment of the ACT, 725 to 762 bp, was isolated by PCR from the genomic DNA of dermatophytes and sequenced. ACT intron-based primers were dermatophyte species-specific and primer pairs crossing the intron were dermatophyte genus-specific. The LightCycler (LC) instrument, employing the two-step RT-PCR/fluorescent hybridization system, was used to quantify the actin mRNA (ACT) of dermatophytes. A 669 bp ACT cDNA fragment was used as a quantification standard. Several mg of samples were collected from skin scales or nail plates before and after the treatment using oral terbinafine. The results indicated that quantification of ACT mRNA correlated with the results of culture and KOH examination and that copy numbers of dermatophyte ACT mRNA per mg sample decreased with progression of the therapy. This method comprises a sensitive (1 fg), specific, rapid (< 4 h) and quantitative assessment of the viability and identification of dermatophytes in skin tissue. 相似文献
10.