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排序方式: 共有10000条查询结果,搜索用时 23 毫秒
991.
992.
Iron overload and liver fibrosis 总被引:1,自引:0,他引:1
MJP ARTHUR 《Journal of gastroenterology and hepatology》1996,11(10):1124-1129
993.
994.
建立溴脱氧尿苷(bromodeoxyuridine,BrdU)免疫细胞化学方法显示增殖细咆.按100mg/kg剂量给鸡腹腔注射DNA合成的前体物质BrdU,6h后处死动物,取小肠组织制备石蜡切片,通过免疫细胞化学方法,成功地显示了小肠上皮细胞中的S期增殖细胞,将此法用于观察鸡内耳感觉上皮细胞的生理性再生状态,结果发现鸡前庭感觉上皮中存在着低水平的增殖活动。BrdU免疫细胞化学方法省时,无需特别防护,且定位准确,是显示增殖细胞的理想方法。 相似文献
995.
急速进入高原人员红细胞免疫粘附功能的动态变化研究 总被引:5,自引:0,他引:5
本文观察了40名快速进入海拔3600米地区人员的RCR、RICR水平,及同海拔移居适应者36名和世居者30名的上述指标。结果表明:观察组进入高原第2天RCR急剧下降,RICR急剧升高,以后逐渐降低或升高,至第30天时与移、世居两组接近(P>0.05);高原反应越重RCR及RICR降低或升高越明显(P<0.05或P<0.01)。 相似文献
996.
Observations on two members of the Swedish family with congenital dyserythropoietic anaemia,type III
S. N. Wickramasinghe A. Wahlin D. Anstee S. F. Parsons G. Stopps I. Bergstrom M. Eriksson H. Sandstrom S. Shiels 《European journal of haematology》1993,50(4):213-221
Abstract: Two affected individuals of the Swedish family with CDA, type III, in which the disease is transmitted as an autosomal dominant character, were studied. Both cases displayed features hitherto undescribed in this family but described in patients with CDA, type III, in whom the inheritance may have been as an autosomal recessive character. Such features were: (a) haemosiderinuria, (b) grossly disorganised erythroblast nuclei, (c) differences in the ultrastructural appearances of individual nuclei within the same multinucleate erythroblast and (d) intraerythroblastic inclusions resembling precipitated globin chains. In both cases the giant mononucleate erythroblasts and the multinucleate erythroblasts had total DNA contents up to 28c (1c = haploid DNA content) and 48c respectively, and some DNA synthesising bi- and multinucleate erythroblasts contained one or more nuclei which were unlabelled with 3H-thymidine. These findings are similar to those in patients with the autosomal recessive type of disease. Thus no major phenotypic differences are yet apparent between cases of CDA, type III, with different patterns of inheritance. Analysis of the surface erythrocyte proteins of the 2 Swedish CDA, type III, patients with monoclonal antibodies recognising Band 3, glycophorins A, B, C and D, Rh, CD44, CD47, CD55, CD58, CD59, Lutheran, Kell, LW and acetylcholinesterase did not reveal any gross abnormality of expression of these proteins. A slightly altered expression of blood group antigens A and H was revealed by the lectins Dolichos biflorus and Ulex europaeus and the Mr of Band 3 as judged by SDS polyacrylamide gel electrophoresis was also slightly reduced, suggesting that there may be minor alterations in the degree of N-glycosylation of some red cell membrane constituents. 相似文献
997.
Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established
model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with
regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders
like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin
cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors.
One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The
experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the
putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed:
(1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic
sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla.
Accepted: 21 August 1996 相似文献
998.
观察上颌窦鳞状细胞癌核仁组成区相关区相关嗜银蛋白的改变,方法:采用胶银染色法对26例上凳窦鳞状细胞癌进行AgNORs检测。 相似文献
999.
High Cell-Density Culture System of Hepatocytes Entrapped in a Three-Dimensional Hollow Fiber Module with Collagen Gel 总被引:2,自引:0,他引:2
Kazuyoshi Takeshita Haruaki Ishibashi Masayuki Suzuki Takumi Yamamoto Toshihiro Akaike Masashi Kodama 《Artificial organs》1995,19(2):191-193
Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 107 cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit. 相似文献
1000.
Fragmentation is frequently observed in animal and human embryosobtained via in-vitro fertilization (IVF), and is known to beassociated with decreased pregnancy rates and poor survivalfollowing cryopreservation. We postulate that embryo fragmentationis a consequence of activated programmed cell death (PCD) andsubsequent apoptosis and discuss evidence of morphological,histological and biochemical features compatible with the occurrenceof PCD in preimplantation embryos. If PCD is an underlying causeof the high incidence of the fragmentation seen in human pre-embryos,it remains to be determined whether this is reflective of thenatural incidence of lethal chromo somes in the human populationor due to the IVF procedure and culture conditions. 相似文献