全文获取类型
收费全文 | 4206篇 |
免费 | 177篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 65篇 |
妇产科学 | 64篇 |
基础医学 | 517篇 |
口腔科学 | 100篇 |
临床医学 | 307篇 |
内科学 | 876篇 |
皮肤病学 | 30篇 |
神经病学 | 380篇 |
特种医学 | 264篇 |
外科学 | 815篇 |
综合类 | 28篇 |
预防医学 | 156篇 |
眼科学 | 30篇 |
药学 | 313篇 |
中国医学 | 6篇 |
肿瘤学 | 451篇 |
出版年
2023年 | 16篇 |
2022年 | 48篇 |
2021年 | 68篇 |
2020年 | 52篇 |
2019年 | 47篇 |
2018年 | 63篇 |
2017年 | 41篇 |
2016年 | 78篇 |
2015年 | 72篇 |
2014年 | 88篇 |
2013年 | 136篇 |
2012年 | 231篇 |
2011年 | 231篇 |
2010年 | 124篇 |
2009年 | 123篇 |
2008年 | 197篇 |
2007年 | 237篇 |
2006年 | 225篇 |
2005年 | 229篇 |
2004年 | 231篇 |
2003年 | 222篇 |
2002年 | 227篇 |
2001年 | 119篇 |
2000年 | 125篇 |
1999年 | 124篇 |
1998年 | 60篇 |
1997年 | 59篇 |
1996年 | 56篇 |
1995年 | 36篇 |
1994年 | 49篇 |
1993年 | 27篇 |
1992年 | 80篇 |
1991年 | 65篇 |
1990年 | 67篇 |
1989年 | 58篇 |
1988年 | 65篇 |
1987年 | 60篇 |
1986年 | 53篇 |
1985年 | 55篇 |
1984年 | 49篇 |
1983年 | 37篇 |
1982年 | 15篇 |
1981年 | 10篇 |
1980年 | 15篇 |
1979年 | 21篇 |
1977年 | 19篇 |
1973年 | 12篇 |
1972年 | 12篇 |
1971年 | 13篇 |
1969年 | 10篇 |
排序方式: 共有4430条查询结果,搜索用时 15 毫秒
1.
Yukako Sato Masahiko Aoyama Tomoko Soeda Akihiko Hoshi Mari Honma Teiji Yamamoto 《Clinical neurology》2004,44(8):527-530
A 65-year-old woman with diabetes mellitus and chronic otitis media developed headache, fever, and hoarseness, all of which did not responded to the oral antibiotics. As stiff neck and lower cranial nerve palsies appeared, bacterial meningitis was suspected. Neurological examination revealed the right hearing disturbance, right recurrent laryngeal nerve palsy, left sternocleidomastoid muscle atrophy and bilateral tongue atrophy. The CSF examination revealed mild pleocytosis and elevated protein, but no bacterial organism was cultured from the CSF. CT scans showed bilateral mastoiditis, and the right mastoid process and a posterior part of the petrous bone were eroded, indicating the exposed bony structures to the posterior fossa. MRI scans demonstrated the thickening of the dura mater of the posterior fossa and the right cerebellar tentorium. This is a rare example of bacterial pachymeningitis of the posterior fossa, the clinical symptoms and MRI findings of which resolved solely by antimicrobial agents without corticosteroid. 相似文献
2.
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
3.
4.
Steady-state net flux of Mg2+ was measured in everted preparations of guinea pig jejunum and ileum, and effects of anoxia, Na+ and Ca2+ concentration, ouabain, and Ca2+ channel blockers were examined. Uphill Mg2+ flux in the mucosal-to-serosal direction was seen in both intestinal segments, with the flux value being 1.5 times greater in the ileum than in the jejenum. The Mg2+ flux was 1.7 times greater than the net Ca2+ flux under the same experimental conditions. The Mg2+ flux was strongly dependent on oxygen and the presence of Na+ in the medium; both anoxia and total replacement of Na+ inhibited the flux by 90-100%. Also, ouabain added to the serosal side, and verapamil or D600 added to the mucosal side, inhibited the flux by about 90%. Inhibitory effects of both ouabain and Na(+)-free conditions were much greater for the Mg2+ flux than for the Ca2+ flux. A stepwise increase in Mg2+ concentration in a Na(+)-free mucosal solution caused a stepwise elevation of the mucosal negativity. The relative elevation of the evoked potential in response to Mg2+ concentration possessed saturable and linearly increasing components. Only the saturable component was found to be dependent on oxygen and sensitive to ouabain. Under the influence of ouabain and verapamil, the generation of the Mg(2+)-evoked potential was greatly inhibited. These findings suggest that Mg2+ is actively absorbed by the jejunum and ileum of the guinea pig, and that active transcellular transport involves a verapamil-sensitive entry step and Na(+)-dependent or ouabain-sensitive exit process which differs from Ca2+ extrusion mechanisms. 相似文献
5.
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
6.
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
7.
Haruo Nagayama Kounosuke Tsuchiyama Kenji Yamada Jotaro Akiyoshi 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):735-744
1. In our series of experiments the role of serotonin in human depression was studied by using animal models of depression.
2. The results of these studies support the hypothesis that some types of human depression may be primarily due to an excessive transmission of serotonin at the synapse. 相似文献
8.
Various kinds of chemical mediators have been implicated in the pathogenesis of bronchial asthma. PGD2 is a cyclooxygenase product which has various physiological effects. In this experimental study, we investigated the role of PGD2 in the pathogenesis of bronchial asthma. In a bioassay system, PGD2 caused dose-dependent contractile responses in non-sensitized guinea pig trachea and lung tissue strips. The subthreshold concentration of PGD2 in both strips was 25 ng/ml. Acetylcholine-induced contractile responses in both strips were significantly increased by continuous infusion of PGD2. In the experimental model of bronchial asthma, the levels of PGD2 were significantly increased in serum, bronchoalveolar lavage fluid (BALF) and lung tissue of sensitized guinea pigs after antigen challenge. We have also reported that the levels of PGD2 in BALF were elevated in patients with stable state bronchial asthma. These results suggest that PGD2 may be a key substance that increases airway responsiveness and induces asthmatic attacks. 相似文献
9.
Hiroaki Hoshi Seishi Jinnouchi Kuniko Harada Katsushi Watanabe 《European journal of nuclear medicine and molecular imaging》1988,14(4):177-179
Gallium scintigraphy was evaluated in 25 patients with adult T-cell leukemia lymphoma (ATLL). Anterior and posterior images were obtained at 72 h after administration of 3 mCi 67Ga-citrate using a gamma camera (Maxi-Camera 400T, General Electric Co.) with a medium energy standard parallel hole collimator. Abnormally high accumulations were observed in 17 out of 25 cases (superficial lymph node, 8; hilar and mediastinal lymph node, 7; paraaortic lymph node, 2; lung, 9; liver, 1; bone, 1). There were 10 malignant lesions detected by 67Ga scintigraphy in 9 out of 17 cases (superficial lymph node, 1; hilar and mediastinal lymph node, 6; paraaortic lymph node, 1; liver, 1; bone, 1). White blood cell count and serum LDH levels were raised in patients with abnormally high accumulations of 67Ga. In conclusion, 67Ga scintigraphy seemed to be a useful examination to detect malignant lesions in patients with ATLL. 相似文献
10.