全文获取类型
收费全文 | 1436篇 |
免费 | 63篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 41篇 |
妇产科学 | 15篇 |
基础医学 | 209篇 |
口腔科学 | 19篇 |
临床医学 | 62篇 |
内科学 | 375篇 |
皮肤病学 | 107篇 |
神经病学 | 110篇 |
特种医学 | 49篇 |
外科学 | 177篇 |
预防医学 | 10篇 |
眼科学 | 3篇 |
药学 | 93篇 |
中国医学 | 15篇 |
肿瘤学 | 194篇 |
出版年
2023年 | 6篇 |
2022年 | 12篇 |
2021年 | 21篇 |
2020年 | 21篇 |
2019年 | 11篇 |
2018年 | 22篇 |
2017年 | 24篇 |
2016年 | 27篇 |
2015年 | 26篇 |
2014年 | 41篇 |
2013年 | 44篇 |
2012年 | 50篇 |
2011年 | 69篇 |
2010年 | 41篇 |
2009年 | 43篇 |
2008年 | 59篇 |
2007年 | 106篇 |
2006年 | 101篇 |
2005年 | 106篇 |
2004年 | 76篇 |
2003年 | 102篇 |
2002年 | 109篇 |
2001年 | 14篇 |
2000年 | 9篇 |
1999年 | 25篇 |
1998年 | 24篇 |
1997年 | 24篇 |
1996年 | 28篇 |
1995年 | 29篇 |
1994年 | 21篇 |
1993年 | 26篇 |
1992年 | 13篇 |
1991年 | 15篇 |
1990年 | 16篇 |
1989年 | 16篇 |
1988年 | 19篇 |
1987年 | 10篇 |
1986年 | 14篇 |
1985年 | 6篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1974年 | 4篇 |
1973年 | 3篇 |
1967年 | 3篇 |
1924年 | 3篇 |
排序方式: 共有1513条查询结果,搜索用时 15 毫秒
1.
2.
Hiroki Sato Atsushi Watanabe Tamotsu Yamaguchi Nobuhiro Harada Akihiko Yamauchi Satomi Inoue Tomio Abe 《Annals of thoracic and cardiovascular surgery》2005,11(1):41-43
Intralobar pulmonary sequestration associated with asymptomatic aspergillosis is a rare case. We describe the case of a 65-year-old woman with intrapulmonary sequestration, anomalous systemic arterial supply to the left lower lobe and aspergillosis who underwent left lower lobectomy and ligation of an anomalous artery by Video-Assisted Thoracoscopic surgery (VATS). Pathological examination showed the parenchymal distortion and chronic inflammation. Aspergillus were found in the cyst. VATS lobectomy for intralobar pulmonary sequestration is a safe and valid procedure. 相似文献
3.
4.
Hiroshi Uno Yoshihiro Izawa Kiyoshi Sagara Tamotsu Koyama Tokutaro Makita Chia-Yuan Hsu-Chang Mitsugi Sugiyama 《Journal of bone and mineral metabolism》1990,8(1):10-16
The effect of 1α-hydroxyvitamin D3 (1α(OH)D3) on the metabolic bone disorders developed in gastrectomized rats were investigated biochemically and histomorphologically.
1α(OH)D3 was suspended in 0.2 % Triton-X-100 aqueous solution after dissolving in a very small amount of ethanol, was given orally
to the rats for 10 weeks. The sham operated animals and the gastrectomy control animals received the vehicle alone. Gastrectomy
was followed by the development of the metabolic bone disorders after 10 weeks of observation. This was characterized by reduction
in ash content of the femur and histologically by a disappearance of the trabecular bone in tibial metaphysis. Decrease Ca
absorption from the intestines was demonstrated by a radiotracer technique. Biochemical studies showed significant decreases
in serum 25(OH)D concentration in gastrectomized rats. These findings suggest that gastrectomy partially impairs intestinal
absorption of calcium and results in a negative calcium balance, which may contribute to the development of bone metabolic
disorders in rats. The administration of 1α(OH)D3 increased dose-dependently serum calcium and Ca absorption from the intestine and prevented the development of bone metabolic
disorders histomorphologically. 相似文献
5.
To examine whether prostacyclin has an attenuating effect on nonspecific bronchial responsiveness in asthma, we measured provocative concentration of methacholine producing a 20% fall in forced expiratory volume in 1 second (PC20-FEV1) before and after oral administration of a chemically stable prostacyclin analog (OP-41483) (200 μg 4 times a day for 4 days) in 8 patients with stable asthma. Neither baseline pulmonary function nor PC20-FEV1 significantly improved after the treatment. These results suggest that prostacyclin may have no direct effect on bronchial responsiveness in asthmatics. Further studies using more potent and long-lasting prostacyclin mimetic will be needed to confirm the conclusion. 相似文献
6.
7.
Emiri Tejima Bing-Qiao Zhao Kiyoshi Tsuji Anna Rosell Klaus van Leyen R Gilberto Gonzalez Joan Montaner Xiaoying Wang Eng H Lo 《Journal of cerebral blood flow and metabolism》2007,27(3):460-468
We tested the hypothesis that astrocytic matrix metalloproteinase-9 (MMP-9) mediates hemorrhagic brain edema. In a clinical case of hemorrhagic stroke, MMP-9 co-localized with astrocytes and neurons in peri-hematoma areas. In a mouse model where blood was injected into striatum, MMP-9 was colocalized with astrocytes surrounding the hemorrhagic lesion. Because MMP-9 is present in blood as well as brain, we compared four groups of wild type (WT) and MMP-9 knockout (KO) mice: WT blood injected into WT brain, KO blood into KO brain, WT blood into KO brain, and KO blood into WT brain. Gel zymography showed that MMP-9 was elevated in WT hemorrhagic brain tissue but absent from KO hemorrhagic brain tissue. Edematous water content was elevated when WT blood was injected into WT brain. However, edema was ameliorated when MMP-9 was absent in either blood or brain or both. To further assess the mechanisms involved in astrocytic induction of MMP-9, we next examined primary mouse astrocyte cultures. Exposure to hemoglobin rapidly upregulated MMP-9 in conditioned media within 1 to 24 h. Hemoglobin-induced MMP-9 was reduced by the free radical scavenger U83836E. Taken together, these data suggest that although there are large amounts of MMP-9 in blood, hemoglobin-induced oxidative stress can trigger MMP-9 in astrocytes and these parenchymal sources of matrix degradation may also be an important factor in the pathogenesis of hemorrhagic brain edema. 相似文献
8.
Haruhiko Ogawa Masaki Fujimura Motoyasu Saito Tamotsu Matsuda Nobuaki Akao Kaoru Kondo 《Clinical autonomic research》1994,4(1-2):19-28
Eosinophilic bronchitis without asthma can cause a persistent non-productive cough which is resistant to bronchodilator therapy. To understand the mechanism of the cough in this disorder, an animal model of eosinophilic bronchitis was developed. Guinea-pigs were treated with transnasal administration of polymyxin B or saline twice a week for 3 weeks. The number of eosinophils in bronchoalveolar lavage fluid increased in polymyxin B-treated animals when compared with those treated with saline. In addition, histological examination showed that the number of eosinophils infiltrated into the tracheal epithelium increased; injury to the tracheal epithelium was greater in polymyxin B-treated animals. The numbers of coughs induced by saline and each concentration of capsaicin (10–18, 10–16, 10–14M) were greater in the polymyxin B-treated animals. FK-224 (a neurokinin receptor antagonist) decreased the heightened cough reflex in this animal model of eosinophilic bronchitis. These findings suggest that neuropeptides, and particularly neurokinins, are involved in the heightened cough receptor sensitivity in eosinophilic bronchitis without asthma. This has implications for better understanding of this disorder and its treatment. 相似文献
9.
Ryozo Oishi Yoshinori Itoh Tamotsu Fukuda Yasunori Araki Kiyomi Saeki 《Journal of neural transmission (Vienna, Austria : 1996)》1988,73(1):65-69
Summary The size of the neuronal and non-neuronal histamine pools in the brain of three different strains of rats was measured by assuming that the -fluoromethylhistidine-induced maximal decrement of histamine represents the size of the neuronal pool. Although the total histamine levels in the brain showed a considerable interstrain variation, no significant interstrain difference was observed in the neuronal histamine level. These results suggest that the size of the neuronal histamine pool in the brain is relatively stable, whereas the size of the non-neuronal histamine pool is variable. 相似文献
10.
Ryozo Oishi Masahiro Nishibori Yoshinori Itoh Kiyomi Saeki Tamotsu Fukuda Yasunori Araki 《Naunyn-Schmiedeberg's archives of pharmacology》1988,337(1):58-63
Summary The turnover of brain histamine was examined in mice implanted subcutaneously with a morphine pellet (50 mg free base). The numbers of naloxone-precipitated jumpings and body shakes were maximum 2 and 3 days after implantation, respectively. The brain tele-methylhistamine level significantly increased (50% to 115%) during 12 h3 days after implantation of a morphine pellet, whereas the histamine level remained unchanged. The accumulation of tele-methylhistamine by pargyline treatment was significantly enhanced when pargyline was administered 12 h after implantation, suggesting an enhancement of histamine turnover. However, a similar degree of the tele-methylhistamine accumulation was induced by pargyline during 1–5 days after implantation, as compared with the accumulation in the control mice implanted with a placebo pellet. In mice undergoing morphine withdrawal by either the removal of morphine pellet or the treatment with naloxone 3 days after implantation, the degree of the pargyline-induced telemethylhistamine accumulation or the (S)--fluoromethylhistidine (-FMH)-induced histamine decrease was similar to that observed in the placebo pellet-control mice. The numbers of naloxone-precipitated jumpings and body shakes occurring in mice 3 days after implantation were not significantly affected by any of l-histidine, -FMH or metoprine. These results suggest that turnover of histamine in the brain is enhanced by acute morphine treatment and returns to the normal rate in the stage of chronic treatment and remains unchanged during the state of withdrawal.
Send offprint requests to K. Saeki 相似文献