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11.
The cellular and regional distribution of glutathione (GSH) and GSH-related enzyme systems involved in cellular defense against reactive oxygen species and electrophilic xenobiotics in the nervous system has been extensively studied. However, little is known about the subcellular distribution of GSH systems in brain tissue and cultured neural cells. The present study investigates the distribution of mitochondrial and cytosolic GSH and GSH-related enzymes in cultured cerebellar astrocytes and granule cells, and compares them with levels in the adult rat cerebellum. Cytosolic GSH levels and cytosolic activities of glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) in astrocytes were 57, 153, 245, and 92% higher than those found in granule cells, respectively. In contrast, granule cells contained significantly higher mitochondrial GSH levels than astrocytes. Granule cells also demonstrated comparable mitochondria/cytosolic concentrations of GSH and GR, GPX and GST activities to those observed in the cerebellar tissue, whereas ratios in astrocytes were markedly lower. Although in vitro treatments with 100 μM ethacrynic acid depleted both cytosolic and mitochondrial GSH in cultured astrocytes and granule cells in a time-dependent fashion, cellular GSH in granule cells was more resistant to the GSH-depleting agent than astrocytes. These results suggest that although GSH and GSH-related enzymes are abundant in cytosolic compartments of astrocytes, mitochondrial pools are relatively small. Since brain mitochondria are sites of significant hydrogen peroxide generation, the mitochondrial localization of GSH and its associated enzymes in neural cells provide important defenses against toxic oxygen species in the nervous system. Differences in subcellular distribution of GSH systems in individual neural cell types may provide a basis for selective cellular and/or subcellular expression of neurotoxicity. 相似文献
12.
用体外培养的人的伪表皮作为模型,进行药物毒理学作用的研究,观察了二甲亚砜(DMSO)在不同浓度和不同接触时间条件下,对人的伪表皮细胞脱氧核糖核酸(DNA)、核糖核酸(RNA)和蛋白质合成的影响:随着接触时间的延长,DNA、RNA和蛋白质合成均受抑制。低浓度条件下(1%),DNA、RNA和蛋白质合成增加;在15~50%浓度下,DNA和蛋白质合成抑制,而RNA合成仍增加;在高浓度条件下(70%~100%),DNA、RNA和蛋白质合成均明显抑制。 相似文献
13.
Kyung Bok Lee Jong Sig Kim Sang Tae Kwak Wonbo Sim Jong Hwan Kwak Yeong Shik Kim 《Archives of pharmacal research》1998,21(5):555-558
Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated
chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action
of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion
of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation
assay and these results suggest that it might be a immunosuppressant. 相似文献
14.
Morphologic characterization of osteoblast-like cell cultures isolated from newborn rat calvaria 总被引:4,自引:0,他引:4
Dominique Masquelier Béatrice Herbert Nadine Hauser Pascal Mermillod Edgard Schonne Claude Remacle Ph.D. 《Calcified tissue international》1990,47(2):92-104
Summary Two methods for harvesting osteoblast-like cell populations from newborn (10 days) rat calvaria were compared. The first one
consisted in culturing the periosteum-free bones and then trypsinizing the cells on the bone surface. The second one involved
the migration of the osteoblasts on glass fragments before trypsinization. Since the plating efficiency, the proportion of
alkaline phosphatase-positive cells, the population doubling time, and the calcium deposition were more adequate, the second
method was used to further characterize the behavior of the cultures. During the first week of culture, the cells featured
shapes similar to those observedin vivo on the surface of periosteum-free calvaria. They formed multilayers and, in the presence of ascorbic acid, synthetized an
organic matrix containing exclusively type I collagen. Later, small amounts of type III collagen appeared. The cells were
embedded in the matrix and progressively acquired the morphologic phenotype of osteocyte-like cells. The matrix mineralized
in the presence of β-glycerophosphate. The technique of dropinoculation (high concentration of cells in a small volume of
medium) promoted the multilayer formation and the achievement of large mineralized plates (about 1 cm2) in 3 weeks of culture. 相似文献
15.
细胞内钙信号的变化调节血管平滑肌细胞增殖 总被引:4,自引:0,他引:4
目的探讨细胞内钙信号的变化对大鼠血管平滑肌细胞(VSMC)增殖作用的影响及其对细胞内信号转导机制的变化。方法以培养的大鼠VSMC为模型,用雷尼丁(RY)剌激VSMC内贮Ca2 释放入胞浆,用3H亮氨酸及3H胸腺嘧啶掺入量作为反应VSMC增殖的指标,加入不同的细胞内信号转导阻断剂,观察对RY效应的影响。结果与对照组相比,RY浓度依赖性地促进细胞内游离钙浓度的增高,差异显著(P<0.05或0.01)。RY剌激组蛋白核酸合成速率明显增高,与对照组相比差异显著(P<0.01);尼卡地平(Nicardipine),蛋白激酶C抑制剂(H7),钙调素激酶(CaMPK)抑制剂(W7)和丝裂素活化蛋白激酶(MAPK)抑制剂(PD98059)能明显抑制RY介导的VSMC蛋白核酸合成速率增高,与RY剌激组相比差异显著(P<0.01)。结论细胞内钙信号的变化明显促进VSMC增殖,但其效应可能通过Ca2 、PKC、MAPK来介导。钙离子拮抗剂可抑制血管平滑肌细胞增殖。 相似文献
16.
动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌功能监测 总被引:3,自引:2,他引:1
目的 比较静态和动态旋转系统中构建组织工程化血管模型中血管内皮细胞分泌功能。方法新型可降解材料聚羟基丁酸酯(PHB),用胶原包埋,形成多孔状PHB 胶原管形支架。分离传代、分化人脐静脉内皮细胞,接种于PHB管型支架内腔面,分别在静态、动态旋转系统中培养14 d后,测定血管内皮细胞分泌一氧化氮(NO)、前列环素(PGI2)水平。结果 在动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌NO、PGI2水平显著高于静态系统,在11 d NO分别为(120.52±3.83)μmmol/L、(80.98±5.98)μmmol/L,PGI2分另9为(20.48±1.52)μg/L,(16.59±1.29)μg/L,与静态系统相比,差异有显著性(P<0.05)。结论胶原包埋PHB支架有利于细胞的黏附和生长,可作为组织工程化血管的支架材料。在动态旋转系统构建组织工程化血管模型中血管内皮细胞,具有与正常血管类似的"生理功能"。 相似文献
17.
ABO血型不合的异基因造血干细胞移植--2例报告附文献复习 总被引:2,自引:1,他引:1
探讨ABO血型不合的异基因造血干细胞移植 (Allo -HSCT)的造血问题。方法 :对 2例患者分别进行异基因外周血造血干细胞移植 (Allo -PBSCT)及脐血造血干细胞移植 (CBSCT) ,用血细胞分离机或 6 %羟乙基淀粉去除移植物中的红细胞 ,定期检测受者血型 ,根据情况输注血细胞。结果 :2例患者全部获得造血重建 ,未出现溶血反应。结论 :ABO血型不合可以进行Allo -HSCT ,去除供者移植物中的红细胞能有效地防止急性溶血反应的发生 ,定期检测受者血型 ,及时调整输血方案有重要的临床意义。 相似文献
18.
P L Randall 《Medical hypotheses》1981,7(2):251-260
It has earlier been proposed by the author that the aetiology of schizophrenic symptomatology may be due to the presence of abnormally connected interhemispheric fibres which link specialised functions in the brains of schizophrenics that are not connected in normal subjects, and that the neuroleptic drugs may produce their action through a local anaesthetic-like effect in suppression of conduction in these fibres. This line of thought has been extended here to consider the possible mechanism of action of the neuroleptic drugs in more detail, as well as that of the tricyclic antidepressant drugs which are derivatives of the phenothiazine group. Pharmacological similarities with the local anaesthetics both structurally and functionally have been considered, as well as the effects that these drug groups may have in common with the lithium salts. It has been suggested that these drugs all produce their primary effect on cell membranes, though not necessarily at the synapse, that the time course of their clinical effect may correlate with their incorporation into various cell membranes within the CNS, and that they may thus bring about a fundamental alteration in cell membrane microstructure. The possible role of electroconvulsive therapy has also been considered. The corollary of this argument is that the affective disorders may be genetically determined diseases of cell membrane microstructure. 相似文献
19.
B. Farkas 《European Surgery》1989,2(1):15-17
Zusammenfassung Bericht über ?dintraoperative maschinelle autotransfusion?, kombiniert mit ?pr?operativer plasmapherese?. Mit maschineller
autotransfusion kann intraoperativer blutverlust durch rückführung eigener erythrozyten halbiert werden. In kombination mit
pr?operativer plasmapherese werden weitere fremdblutkonserven eingespart. übertragung von infektionskrankheiten und erzeugung
irregul?rer antikōrper kōnnen verhindert werden. Bei der derzeitigen AIDS-situation wird das infektionsrisiko auf null reduziert.
相似文献
20.
LRIG1下调原代星形细胞瘤细胞增殖的机制 总被引:1,自引:0,他引:1
目的观察LRIGl蛋白表达对表皮生长因子(EGF)促肿瘤细胞增殖作用的影响,探讨LRIGl抑制肿瘤细胞增殖的机制。方法原代培养19例星形细胞瘤细胞,用原位杂交检测LRIGl的表达,用噻唑蓝(MTT)法观察EGF对培养细胞的促增殖作用,并分析培养细胞LRIGl表达和EGF干预后的细胞生长率的关系。结果(75.3±11.6)%的培养细胞表达LRIGl蛋白;EGF促进培养细胞增殖(38.0±14.8)%,EGF促细胞增殖的细胞生长率与LRIGl表达程度呈负相关。结论LRIGl蛋白可能通过抑制EGF—EGFR信号抑制肿瘤细胞的增殖。 相似文献