全文获取类型
收费全文 | 10848篇 |
免费 | 563篇 |
国内免费 | 105篇 |
专业分类
耳鼻咽喉 | 112篇 |
儿科学 | 198篇 |
妇产科学 | 129篇 |
基础医学 | 1226篇 |
口腔科学 | 144篇 |
临床医学 | 743篇 |
内科学 | 3133篇 |
皮肤病学 | 192篇 |
神经病学 | 726篇 |
特种医学 | 333篇 |
外科学 | 2078篇 |
综合类 | 64篇 |
预防医学 | 295篇 |
眼科学 | 131篇 |
药学 | 683篇 |
中国医学 | 34篇 |
肿瘤学 | 1295篇 |
出版年
2024年 | 8篇 |
2023年 | 109篇 |
2022年 | 214篇 |
2021年 | 352篇 |
2020年 | 198篇 |
2019年 | 270篇 |
2018年 | 356篇 |
2017年 | 212篇 |
2016年 | 335篇 |
2015年 | 340篇 |
2014年 | 418篇 |
2013年 | 466篇 |
2012年 | 841篇 |
2011年 | 878篇 |
2010年 | 463篇 |
2009年 | 380篇 |
2008年 | 694篇 |
2007年 | 741篇 |
2006年 | 676篇 |
2005年 | 697篇 |
2004年 | 626篇 |
2003年 | 523篇 |
2002年 | 591篇 |
2001年 | 99篇 |
2000年 | 86篇 |
1999年 | 93篇 |
1998年 | 107篇 |
1997年 | 100篇 |
1996年 | 74篇 |
1995年 | 68篇 |
1994年 | 74篇 |
1993年 | 60篇 |
1992年 | 38篇 |
1991年 | 35篇 |
1990年 | 26篇 |
1989年 | 26篇 |
1988年 | 33篇 |
1987年 | 24篇 |
1986年 | 17篇 |
1985年 | 22篇 |
1984年 | 27篇 |
1983年 | 23篇 |
1982年 | 10篇 |
1981年 | 21篇 |
1980年 | 15篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 10篇 |
1975年 | 5篇 |
1974年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Shin-ichi Hirano Naoki Agata Yutaka Hara Hiroshi Iguchi Masataka Shirai Hiroshi Tone Norimoto Urakawa 《Cancer chemotherapy and pharmacology》1991,28(4):266-272
Summary In the present study we examined the effects of pirarubicin [(2R)-4-0-tetrahydropyranyladriamycin, THP] on a cardiovascular system. An injection of THP (0.39–3.13 mg/kg, i. v.) reduced the mean blood pressure and caused an increase in the respiratory air rate in anesthetized rats. At 1.5×10–6–1.5×10–5
m, THP markedly relaxed a contraction induced by 10–7
m norepinephrine in rat aorta with endothelium but not in that without endothelium. At a dose of 0.02–0.5 mg, THP produced an increase in the contractile force and the perfusion flow of isolated perfused guinea pig hearts. At a higher concentration (4.5×10–5–1.5×10–4
m), it produced a slight increase in the contractile force of the left atria in guinea pigs. This positive inotropic action of THP was inhibited by diphenhydramine (10–6–5×10–5
m), chlorpheniramine (3×10–7–3×10–5
m), and tripelennamine (3×10–7–3×10–5
m) but not by propranolol (10–6
m), cimetidine (10–5
m), diltiazem (10–6
m), or ryanodine (10–8
m). THP given i. v. at 2.5 mg/kg elevated the plasma histamine level in anesthetized dogs. From these data, we conclude that THP mainly relaxed the rat aorta in the presence of endothelium and that at higher concentrations, it increased the contractile force in the cardiac muscle, probably mediated through the release of histamine. 相似文献
92.
Naoki Matsushiro Takashi Sato Takako Iwaki Katsumi Doi Takeshi Kubo 《Nihon Jibiinkoka Gakkai kaiho》2003,106(3):211-219
Six cochlear implant recipients with hearing aids in the opposite ear were studied to survey binaural advantage. They were examined in separate tests by using a hearing aid alone, cochlear implant alone, and by using both devices (bimodal condition). Test items used were the Japanese monosyllable word list 67--S and Japanese HINT. Statistically significantly results were obtained in the bimodal condition, three out of six subjects were successful in the monosyllable word test and all successful in the Japanese HINT. We conclude that all subjects enjoyed binaural advantage in speech perception in bimodal condition with no conflict at the recognition level; even when different sounds from cochlear implant and contralateral hearing aid were received. The plasticity of the brain is thought to be of importance in the bimodal condition. 相似文献
93.
94.
95.
Makoto Okada Junzo Kigawa Yukihisa Minagawa Yasunobu Kanamori Hiroaki Itamochi Xiusi Cheng Tetsuro Ohishi Naoki Terakawa 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(4):240-246
Background A role for theTP53 (alias p53) tumor-suppressor gene in chemoresistance has recently been discussed, but little is known about the clinical
relevance of theTP53 gene to chemoresistance. To elucidate the relevance ofTP53 status to chemoresistance, we investigated theTP53 gene and TP53 protein expression in tumors from the same patients, before and after chemotherapy.
Methods Twenty-one patients with ovarian cancer, who had residual disease after primary surgery, were studied. These patients received
chemotherapy consisting of cisplatin, doxorubicin, and cyclophosphamide, and then underwent a second surgery. Polymerase chain
reaction-single strand conformation polymorphism analysis and cycle sequencing were performed to determineTP53 mutation. TP53 protein was detected by Western blot analysis.
Results Of the 21 patients studied, 9 responded to chemotherapy. Mutation of theTP53 gene was seen in 7 patients (2 responders and 5 nonresponders) before chemotherapy. After chemotherapy, another mutation
of the gene was observed in 5 patients, all of whom were nonresponders. TP53 protein was detected in 10 patients (3 responders
and 7 nonresponders) before chemotherapy. After chemotherapy, the expression of TP53 protein increased in these 3 nonresponders,
and became positive in 2 other nonresponders.
Conclusions This study showed for the first time in clinical investigation that alterations toTP53 could develop in association with chemotherapy, and thatTP53 status may relate to the mechanisms of chemoresistance in patients with epithelial ovarian cancer. 相似文献
96.
97.
Takeo Shimo Naoki Ashizawa Koji Matsumoto Takashi Nakazawa Osamu Nagata 《Toxicological sciences》2005,87(1):267-276
The possible mechanism of the underlying nephropathy found in the rat toxicity study of FYX-051, a xanthine oxidoreductase inhibitor, was investigated. Rats received oral treatment of either 1 or 3 mg/kg of FYX-051, with and without citrate for four weeks to elucidate whether nephropathy could be caused by materials deposited in the kidney. Furthermore, analysis of the renal deposits in rats was also performed. Consequently, interstitial nephritis comprising interstitial inflammatory cell infiltration, dilatation, basophilia and epithelial necrosis of renal tubules and collecting ducts, deposits in renal tubules and collecting ducts, and so forth was seen in six of the eight rats and in all eight rats in the 1 and 3 mg/kg FYX-051 alone groups, respectively, with the intensity in the 3 mg/kg group being moderate to severe. In the simultaneous treatment with citrate group, however, no alterations were observed in the kidney, except for minimal interstitial nephritis in one instance in the 3 mg/kg FYX-051 + citrate group along with an increased urinary pH, leading to an increase in xanthine solubility. Analysis of intrarenal deposits showed that the entity would be composed of xanthine crystals. The present study, therefore, showed that nephropathy in rats occurring after the administration of FYX-051 was a secondary change caused by xanthine crystals being deposited in the kidney, and no other causes could be implicated in this kidney lesion. 相似文献
98.
Carbonic anhydrase II is a tumor vessel endothelium-associated antigen targeted by dendritic cell therapy. 总被引:3,自引:0,他引:3
Kenta Yoshiura Takashi Nakaoka Toshihide Nishishita Katsuaki Sato Akifumi Yamamoto Shinji Shimada Toshiaki Saida Yutaka Kawakami Tsuneo A Takahashi Hiroyuki Fukuda Shinobu Imajoh-Ohmi Naoki Oyaizu Naohide Yamashita 《Clinical cancer research》2005,11(22):8201-8207
Tumor-associated antigens are promising candidates as target molecules for immunotherapy and a wide variety of tumor-associated antigens have been discovered through the presence of serum antibodies in cancer patients. We previously conducted dendritic cell therapy on 10 malignant melanoma patients and shrinkage or disappearance of metastatic tumors with massive necrosis occurred in two patients. In this study, we found a 29-kDa protein against which antibody was elicited by dendritic cell therapy in one of the two patients. Matrix-assisted laser desorption ionization-time of flight/mass spectrometry analysis of the protein isolated by two-dimensional electrophoresis combined with Western blots revealed that the 29-kDa protein was carbonic anhydrase II (CA-II). Immunohistochemistry of the tumors and normal tissues showed that CA-II was expressed in the tumor vessel but not in normal vessel endothelium. CA-II expression in tumor endothelium was observed as well in other cancers including esophageal, renal, and lung cancers. In an in vitro angiogenesis model, CA-II expression of normal human vein endothelial cells was significantly up-regulated when cells were cultured in the acidic and hypoxic conditions indicative of a tumor environment. These findings suggest that CA-II is a tumor vessel endothelium-associated antigen in melanoma and other cancers, and elicitation of serum anti-CA-II antibody by dendritic cell therapy may be associated with good clinical outcome including tumor reduction. 相似文献
99.
Naoki Ishiguro Takashi Nozawa Akiko Tsujihata Asami Saito Wataru Kishimoto Kazutoshi Yokoyama Takafumi Yotsumoto Kenji Sakai Takashi Igarashi Ikumi Tamai 《Drug metabolism and disposition》2004,32(5):519-524
We investigated influx and efflux transporters involved in blood-brain barrier transport of the nonsedative H1-antagonist epinastine. The basal-to-apical transport of [14C]epinastine was markedly higher than that in the opposite direction in LLC-GA5-COL150 cells stably transfected with human multidrug resistance (MDR)1 gene. The brain-to-plasma concentration ratio of [14C]epinastine in mdr1a/b(-/-) mice was 3.2 times higher than that in wild-type mice. The uptake of both [3H]mepyramine and [14C]epinastine into immortalized rat brain capillary endothelial cells (RBEC)1 showed temperature and concentration dependence. The kinetic parameters, K(m), V(max), and uptake clearance (V(max)/K(m)), of the initial uptake of [3H]mepyramine and [14C]epinastine by RBEC1 were 150 microM, 41.8 nmol/min/mg protein, and 279 microl/min/mg protein for mepyramine and 10.0 mM, 339 nmol/min/mg protein, and 33.9 microl/min/mg protein for epinastine, respectively. The uptake of [3H]mepyramine and [14C]epinastine by RBEC1 was inhibited by organic cations such as quinidine, amantadine, and verapamil, but not by other organic cations, tetraethyl ammonium, guanidine, and carnitine. Organic anions such as benzoic acid, estrone-3-sulfate, taurocholate, and neutral digoxin were not inhibitory. Furthermore, some cationic H1 antagonists (chlorpheniramine, cyproheptadine, ketotifen, and desloratadine) inhibited the [3H]mepyramine and [14C]epinastine uptake into RBEC1. In conclusion, the present study demonstrated that the combination of efficient efflux transport by P-glycoprotein and poor uptake by the influx transporter, which is identical with that responsible for the uptake of mepyramine, account for the low brain distribution of epinastine. 相似文献
100.