全文获取类型
收费全文 | 25444篇 |
免费 | 1237篇 |
国内免费 | 156篇 |
专业分类
耳鼻咽喉 | 201篇 |
儿科学 | 375篇 |
妇产科学 | 247篇 |
基础医学 | 2956篇 |
口腔科学 | 514篇 |
临床医学 | 1492篇 |
内科学 | 6274篇 |
皮肤病学 | 1296篇 |
神经病学 | 2240篇 |
特种医学 | 967篇 |
外科学 | 4817篇 |
综合类 | 159篇 |
预防医学 | 596篇 |
眼科学 | 246篇 |
药学 | 1925篇 |
中国医学 | 61篇 |
肿瘤学 | 2471篇 |
出版年
2023年 | 141篇 |
2022年 | 282篇 |
2021年 | 514篇 |
2020年 | 248篇 |
2019年 | 364篇 |
2018年 | 465篇 |
2017年 | 387篇 |
2016年 | 501篇 |
2015年 | 529篇 |
2014年 | 712篇 |
2013年 | 776篇 |
2012年 | 1333篇 |
2011年 | 1364篇 |
2010年 | 756篇 |
2009年 | 678篇 |
2008年 | 1239篇 |
2007年 | 1341篇 |
2006年 | 1346篇 |
2005年 | 1298篇 |
2004年 | 1352篇 |
2003年 | 1306篇 |
2002年 | 1275篇 |
2001年 | 686篇 |
2000年 | 724篇 |
1999年 | 743篇 |
1998年 | 373篇 |
1997年 | 262篇 |
1996年 | 256篇 |
1995年 | 215篇 |
1994年 | 190篇 |
1993年 | 187篇 |
1992年 | 474篇 |
1991年 | 426篇 |
1990年 | 432篇 |
1989年 | 451篇 |
1988年 | 420篇 |
1987年 | 389篇 |
1986年 | 343篇 |
1985年 | 296篇 |
1984年 | 182篇 |
1983年 | 159篇 |
1982年 | 94篇 |
1981年 | 74篇 |
1979年 | 172篇 |
1978年 | 90篇 |
1977年 | 91篇 |
1974年 | 74篇 |
1973年 | 82篇 |
1972年 | 87篇 |
1970年 | 75篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
The structure-acute toxicity relationship of aromatic hydrocarbons was examined in mice. In all test compounds, the acute toxicity was determined under 2 conditions: control LD50 (LD50-cont) and carbon tetrachloride (CCl4)-pretreated LD50 (LD50-CCl4). The CCl4-pretreatment was done in order to evaluate the toxic potency of compound itself without the influence of metabolism. Both log (1/LD50-cont) and log (1/LD50-CCl4) were functions of the log P, n-octanol/water partition coefficient, i.e., log (1/LD50-cont) = 0.080 log P − 1.532 and log (1/LD50-CCl4) = −0.040(log P)2 + 0.157 log P − 1.373. Both equations were statistically significant (P < 0.01). The ratio of LD50-cont/LD50-CCl4 indicated that metabolic activation is more evident in hydrophobic compounds than in hydrophilic compounds. The results suggest that hydrophobicity of the aromatic hydrocarbons plays an important role in determining their acute toxicity. 相似文献
62.
Akihiko Usui Fumihiko Murakami Hideki Ooshima Yasuhiro Tomita Katsuhiko Yoshida Michiaki Hibi Mitsuo Kawamura Mitsuya Muras 《Artificial organs》1997,21(7):772-778
Abstract: Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty-two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL-6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than -5, blood glutamic-oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin-coated system (CB Maxima or AL-6000 with CB BP-80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than -5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188). 相似文献
63.
Masanori Hisaoka Takatoshi Aoki Hiromi Kouho Hirofumi Chosa Hiroshi Hashimoto 《Skeletal radiology》1997,26(3):191-194
The case of a 49-year-old man with Maffucci’s syndrome, who developed multiple spindle cell hemangioendotheliomas, is presented.
The case provides support for recent reports suggesting an association between this peculiar vascular lesion and skeletal
enchondromatosis. 相似文献
64.
We have successfully applied a reverse flow island flap of extensor digitorum brevis muscle for coverage of tissue defects in the distal portion of the foot dorsum in 2 patients. This flap covered the metatarsophalangeal area well with cadaver limb dissection and seems useful to cover the defect in the distal foot dorsum. 相似文献
65.
66.
Seietsu Nyui Hiroyuki Osanai Hideji Masuoka Shigeri Ohba Toshiaki Ebata Yukinari Yoshida Hideki Hoshi Yoshifumi Shinohara 《Surgery today》1997,27(4):349-352
Primary extranodal malignant lymphoma frequently occurs in the gastrointestinal tract; however, it is rarely encountered in the rectum. We report herein the case of an 85-year-old man who underwent abdominoperineal resection for primary malignant lymphoma of the rectum, and 1 year later, developed hematemesis caused by gastric metastasis. To our knowledge this is the first case report of such distant metastasis developing from malignant lymphoma of the rectum. 相似文献
67.
Takao Hashimoto Osamu Sasaki Kunihiro Yoshida Yo-ichi Takei Shu-ichi Ikeda 《Movement disorders》2003,18(10):1201-1204
We report on a family with ataxia type 6 (SCA6) showing peculiar oculomotor symptoms. The proband presented with periodic alternating nystagmus (PAN), and her 2 brothers had rebound nystagmus and gaze-evoked nystagmus. They carried the identical mutation (the number of expanded CAG repeat, 24) in the CACNA1A gene. The intrafamilial variability of oculomotor symptoms may be ascribed to factors other than CAG repeat expansion size in SCA6. 相似文献
68.
Sadahisa Okamoto Yuichiro Inatomi Toshiro Yonehara Yoichiro Hashimoto Teruyuki Hirano Makoto Uchino 《Clinical neurology》2006,46(5):307-311
In order to determine predictive factors of early seizures (ES) after acute stroke and to estimate prognosis, we retrospectively examined clinical data of 1,743 consecutive patients with acute ischemic stroke. The subjects were divided into two groups; an ES group (19 patients) and a non-ES group (1,724 patients). Multivariate statistical analysis revealed that the NIH-Stroke Scale score on admission (/10, OR, 1.1: 95% CI 1.04 to 1.13) and positive past history of cerebrovascular disease or brain injury (OR, 3.85: 95% CI 1.49 to 9.95) are significant factors to predict ES. There was no significant difference in the outcome between the two groups. A recurrence of seizures, after follow up for 4 to 40 months, was observed only in one patient with a history of ES. 相似文献
69.
Kazuhiro Masada Masataka Yasuda Eiji Takeuchi Hideo Hashimoto 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2003,37(3):155-158
We did 18 arthrodeses of the wrist in 16 patients with rheumatoid arthritis using an intramedullary fixation technique. There were 15 women and one man, whose ages at operation ranged from 47 to 71 years (mean 58). Follow up ranged from 13 to 68 months (mean 27). The operative technique consists of a combination of intramedullary placement of two Kirschner (K)-wires and an autogenous bone graft. At follow up bony union was apparent in all cases. K-wires came out of the metacarpal joints in two cases. Paraesthesiae in the median nerve distribution occurred in two cases which both recovered within three months. 相似文献
70.
Akihiko Hashi Tsutomu Yuminamochi Shin-Ichi Murata Hideki Iwamoto Tsuyoshi Honda Kazuhiko Hoshi 《International journal of gynecological pathology》2003,22(4):374-377
Wilms tumor gene (WT-1) expression has been reported in many human cancers, including most ovarian and peritoneal serous carcinomas, but has not been studied in carcinomas of the fallopian tube. In this study, the authors evaluated the immunohistochemical expression of WT-1 in serous carcinomas of the fallopian tube and compared their reactivity with that of ovarian, peritoneal, and endometrial serous carcinomas. All primary serous carcinomas of the fallopian tube (13 cases), ovaries (25 cases), and peritoneum (3 cases) were reactive with the WT-1 antibody, whereas all five primary endometrial serous carcinomas were nonreactive. WT-1 reactivity in an unknown primary serous carcinoma is therefore suggestive of an extrauterine site. The marked difference in WT-1 staining raises the possibility of genetic differences between serous carcinomas arising in the endometrium compared with those arising in the ovaries, fallopian tubes, and peritoneum. 相似文献