全文获取类型
收费全文 | 588篇 |
免费 | 23篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 59篇 |
妇产科学 | 6篇 |
基础医学 | 55篇 |
口腔科学 | 4篇 |
临床医学 | 63篇 |
内科学 | 137篇 |
皮肤病学 | 44篇 |
神经病学 | 63篇 |
特种医学 | 2篇 |
外科学 | 90篇 |
综合类 | 4篇 |
预防医学 | 12篇 |
眼科学 | 2篇 |
药学 | 39篇 |
肿瘤学 | 29篇 |
出版年
2022年 | 5篇 |
2021年 | 10篇 |
2017年 | 7篇 |
2016年 | 10篇 |
2015年 | 11篇 |
2014年 | 13篇 |
2013年 | 11篇 |
2012年 | 13篇 |
2011年 | 3篇 |
2010年 | 14篇 |
2009年 | 15篇 |
2008年 | 10篇 |
2007年 | 15篇 |
2006年 | 49篇 |
2005年 | 18篇 |
2004年 | 8篇 |
2003年 | 13篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 10篇 |
1998年 | 37篇 |
1997年 | 44篇 |
1996年 | 37篇 |
1995年 | 32篇 |
1994年 | 22篇 |
1993年 | 18篇 |
1992年 | 16篇 |
1991年 | 16篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 9篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1972年 | 2篇 |
1970年 | 4篇 |
1968年 | 2篇 |
1959年 | 4篇 |
1958年 | 5篇 |
1957年 | 13篇 |
1956年 | 15篇 |
1955年 | 13篇 |
1954年 | 11篇 |
排序方式: 共有611条查询结果,搜索用时 46 毫秒
11.
TETSUYA TAKAHASHI HIROSHI YAMASHITA YU-XIANG ZHANG SHIGENOBU NAKAMURA 《Brain research bulletin》1996,41(6):363-367
In the present study, we examined the effect of amantadine on extracellular dopamine levels in the rat striatum using an in vivo microdialysis. Perfusion of amantadine (0.1–1 mM) through the microdialysis probe caused an increase both in extracellular dopamine and glutamate levels in rat striatum. Amantadine was found to increase extracellular dopamine concentration in Ca2+-dependent manner, but the effect was not abolished by ω-conotoxin. Although intraperitoneal administration of MK-801 [(+)-5-methyl-10,11-dihydroxy-5H-dibenzo(a,d)cyclohepten-5,10-imine] alone could not significantly alter the concentration of dopamine, it attenuated amantadine-induced increase in dopamine level. These findings suggest that an interaction between dopaminergic and glutamatergic neurotransmission is an important component in the regulation of striatal dopamine levels. Copyright © 1996 Elsevier Science Inc. 相似文献
12.
Matsumoto Y Hayashi T Inagaki N Takahashi M Hiroi S Nakamura T Arimura T Nakamura K Ashizawa N Yasunami M Ohe T Yano K Kimura A 《Journal of muscle research and cell motility》2005,26(6-8):367-374
Hypertrophic cardiomyopathy and dilated cardiomyopathy are two major clinical phenotypes of “idiopathic” cardiomyopathy. Recent molecular genetic analyses have now revealed that “idiopathic” cardiomyopathy is caused by mutations in genes for sarcomere components. We have recently reported several mutations in titin/connectin gene found in patients with hypertrophic cardiomyopathy or dilated cardiomyopathy. A hypertrophic cardiomyopathy-associated titin/connectin mutation (Arg740Leu) was found to increase the binding to actinin, while other dilated cardiomyopathy-associated titin/connectin mutations (Ala743Val and Val54Met) decreased the binding to actinin and Tcap/telethonin, respectively. We also reported several other mutations in the N2-B region of titin/connectin found in hypertrophic cardiomyopathy and dilated cardiomyopathy. Since the N2-B region expresses only in the heart, it was speculated that functional alterations due to the mutations cause cardiomyopathies. In this study, we investigated the functional changes caused by the N2-B region mutations by using yeast-two-hybrid assays. It was revealed that a hypertrophic cardiomyopathy-associated mutation (Ser3799Tyr) increased the binding to FHL2 protein, whereas a dilated cardiomyopathy-associated mutation (Gln4053ter) decreased the binding. In addition, another TTN mutation (Arg25618Gln) at the is2 region was found in familial DCM. Because FHL2 protein is known to tether metabolic enzymes to N2-B and is2 regions of titin/connectin, these observations suggest that altered recruitment of metabolic enzymes to the sarcomere may play a role in the pathogenesis of cardiomyopathies. 相似文献
13.
IKURO KIMURA YOSHIRO TANIZAKI KATSUYOSHI SAITO KIYOSHI TAKAHASHI NOBUO UEDA SHUICHI SATO 《Clinical and experimental allergy》1975,5(1):95-98
A total of 108 samples of sputum obtained from twenty patients with bronchial asthma were examined for appearance of basophils and eosinophils. Both cell types are present in sputum during an asthmatic attack and disappear at the conclusion of the attack. Their presence correlates with the severity of the disease. It has previously been demonstrated that the blood basophils count falls during attacks of bronchial asthma, and the present study suggests that basophils move from the blood stream into bronchial tissue during the acute phase of an asthmatic attack. 相似文献
14.
SHINZO NISHI YOSHIHIDE FUJIYAMA HIDEMATSU HIRAI 《Scandinavian journal of immunology》1978,8(S8):305-308
A simple and sensitive determination method of α-fetoprotein was developed by introducing α-fetoprotein horseradish peroxidase conjugate into electroimmunodiffusion.
The precipitin line formed was directly visualized by staining for peroxidase activities. The sensitivity was 32 ng/ml. Electrophoretic activities of AFP were analyzed by two dimensional electrophoresis applying the present method to the second electrophoresis.
AFP from normal adults and several patients was confirmed to migrate as an α-globulin as AFP of hepatoma, yolk sac tumor and fetuses did.
AFP-like activities were detected in β-γ-globulin region in some samples but these were not due to AFP-anti-AFP interactions. 相似文献
The precipitin line formed was directly visualized by staining for peroxidase activities. The sensitivity was 32 ng/ml. Electrophoretic activities of AFP were analyzed by two dimensional electrophoresis applying the present method to the second electrophoresis.
AFP from normal adults and several patients was confirmed to migrate as an α-globulin as AFP of hepatoma, yolk sac tumor and fetuses did.
AFP-like activities were detected in β-γ-globulin region in some samples but these were not due to AFP-anti-AFP interactions. 相似文献
15.
Ion Channels and Early Development of Neural Cells 总被引:4,自引:0,他引:4
16.
17.
Ryo KANEMATSU Junya HANAKITA Toshiyuki TAKAHASHI Manabu MINAMI Tomoo INOUE Fumiaki HONDA 《Neurologia medico-chirurgica》2021,61(1):40
Posterior stabilization is a common surgical procedure, which aims for rigid stabilization by facet fusion. Facet non-union has a potential risk of the screw loosening and malalignment. Although some authors have reported the influencing factors about screw loosening in the lumbar spine, there are few reports about the risk factor contributing to the facet non-union in the cervical spine. In all, 22 patients (78 facets and 122 screws) with degenerative cervical kyphosis or spondylolisthesis who underwent decompression and lateral mass screw (LMS) fixation were analyzed. Age, gender, smoking, bone mineral density (BMD), the degree of facet decortication with bone packing, and screw loosening were investigated as risk factors contributing to the facet non-union at each segmental fused level. Facet fusion rate was 85.9% (67/78 facets) and the incidence of loosening was 4.9% (6/122 screws, 4 patients). Insufficient facet decortication with bone packing is a significant risk factor of facet non-union (p <0.05, odds ratio: 26.5). All six loosened screws were associated with bony non-union of the facet and were located in the uppermost or lowermost vertebrae. Comparing loosened screws and stable screws, the average maximal insertional screw torque (MIT) was 9.8 cNm and 39.5 cNm, respectively (p <0.05). Additionally, the length of the stable screws was significantly longer versus the loosened screws (p <0.05). Lower MIT and shorter screw length located near the ends of the lateral mass may predict loosening, which can lead to facet non-union. Sufficient facet decortication with bone packing is one of the important factors contributing to the facet fusion. 相似文献
18.
Differences in the Mode of Lethality Produced through Intravenous and Oral Administration of Organophosphorus Insecticides in Rats 总被引:2,自引:0,他引:2
TAKAHASHI HIROAKI; KOJIMA TAKESHI; IKEDA TAKANORI; TSUDA SHUJI; SHIRASU YASUHIKO 《Toxicological sciences》1991,16(3):459-468
Differences in the Mode of Lethality Produced through Intravenousand Oral Administration of Organophosphorus Insecticides inRats. TAKAHASHI, H., KOJIMA, T., IKEDA, T., TSUDA, S. and SHIRASU,Y. (1991). Fundam. Appl. Toxicol. 16, 459468. This studywas undertaken to investigate the possibility that mechanismsother than cholinesterase (ChE) inhibition account for the acutetoxicity of organophosphorus insecticide. Both the PO type insecticide(direct ChE inhibitors: chlorfenvinphos and dichlorvos) andthe PS type insecticide (indirect ChE inhibitors: diazinon andfenthion) were employed. Rats treated with lethal doses of intravenousand oral PO type insecticides and oral PS type insecticidesexhibited typical signs of anti-ChE poisoning along with markedinhibition of brain and erythrocyte ChE activity. In contrast,rats given lethal doses of intravenous PS type insecticidesexhibited tonic convulsions and opisthotonos, with only slightinhibition of ChE activities. When PO type insecticides wereintravenously administered to anesthetized and conscious rats,animals exhibited typical anti-ChE poisoning signs in cardiorespiration:hypertension and apnea which were antagonized by atropine. Afteradministration of lethal doses of PO type insecticides, breathingdisappeared before the cessation of heart beats. Rats receivinglethal doses of intravenous PS type insecticides did not showhypertension, but exhibited transient cessation of breathingand heart beats. Breathing was observed after the disappearanceof heart beats. The electroencephalogram (EEG) was characterizedby spike and wave complexes. The EEG and cardiorespiratory changeswere not antagonized by atropine. It was concluded that lethalityfollowing intravenous PS type insecticides may be independentof ChE inhibition. 相似文献
19.
Combined Repeat Dose and Reproductive/Developmental Toxicity Screening Test (OECD): Familiarization Using Cyclophosphamide 总被引:1,自引:0,他引:1
TANAKA SATORU; KAWASHIMA KUNIO; NAITO KATSUSHI; USAMI MAKOTO; NAKADATE MASAHIRO; IMAIDA KATSUMI; TAKAHASHI MICHIHITO; HAYASHI YUZO; KUROKAWA YUJI; TOBE MASUO 《Toxicological sciences》1992,18(1):89-95
Combined Repeat Dose and Reproductive/Developmental ToxicityScreening Test (OECD): Familiarization Using Cyclophosphamide.TANAKA, S., KAWASHIMA, K., NAITO, K., USAMI, M., NAKADATE, M.,IMAIDA, K., TAKAHASHI, M., HAYASHI, Y., KUROKAWA, Y., AND TOBE,M. (1992A, Y., AND TOBE, M. (1992). Fundam. Appl. Toxicol. 18,8995. A familiarization study was conducted on the "Combined RepeatDose and Reproductive/Developmental Toxicity Screening Test(ReproTox)" proposed by the OECD. Cyclophosphamide (CP) at dosesof 6.7, 4.5, 3, 2, and 0 mg/kg body wt was given daily by gavageto groups of 12 male and 12 female Sprague-Dawley rats. As aresult, anemia and leukopenia were evident in treated males.The absolute and relative thymus and spleen weights were decreasedin treated rats. Histopathologically, atrophy of the thymus,spleen, and bone marrow was observed. With respect to the reproductive/developmentaltoxicity, dose-dependent increases in postimplantation lossof fetuses and postnatal death were found in dams given CP.The body weight of pups treated with CP was significantly loweredin a dose-related manner. Thus the results demonstrated mostof the known toxicological properties of CP, except the adverseeffects on spermatogenesis and fertility. Therefore ReproToxcan be considered as a useful screening test for assessing repeatdose and reproductive/developmental toxicity of existing chemicalsof high production volume. 相似文献
20.