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81.
The protective effect of affinity purified antigen has been investigated in an experimental model for malaria which shows a well marked recrudescence of parasitaemia, a feature of the disease in man. A monoclonal antibody (MoAb) recognizing an epitope common to two genetically distinct cloned lines of Plasmodium chabaudi (AS and CB), was used to purify a Mr250,000 polymorphic schizont antigen (PSA) from these parasites. The purified preparations were then examined for the presence of specific and cross-reactive epitopes by immunoprecipitation with a panel of MoAb raised against P. chabaudi AS. When tested previously on smears of parasitized blood by immunofluorescence, or against lysates of parasitized erythrocytes by immunoprecipitation, most of these MoAb had been found to be AS specific. When either AS or CB affinity purified Mr250,000 PSA was used as the target, these same MoAb immunoprecipitated both antigens, and in some cases, a number of associated polypeptides (AP) which copurify with the Mr250,000 PSA. Subsequently, mice were immunized with either the purified AS or CB antigens in Freund's complete adjuvant (FCA). Prechallenge sera were compared by indirect immunofluorescence and immunoprecipitation. Sera from mice immunized with AS antigen reacted strongly with AS and cross-reacted with CB parasite preparations. Pre-challenge serum from CB antigen immunized mice reacted well with CB, but only faintly with AS preparations. In mice immunized with the AS antigen and then challenged with either AS or CB parasites, the initial parasitaemias were delayed in appearance and the height of the peak parasitaemia reduced, an effect which was most pronounced after challenge with homologous parasites. Only homologous challenge of the mice immunized with CB antigen produced statistically significant modification of the initial parasitaemia. In the immunized mice challenged with homologous parasites, the delayed appearance and slightly reduced peak of the primary parasitaemia was associated with delayed resolution of the patent parasitaemia and significant enhancement of the recrudescence. 相似文献
82.
Monoclonal antibodies to intermediate filament proteins: Diagnostic specificity in orbital pathology
Thomas D. Lindquist M.D. Ph.D. James C. Orcutt M.D. Ph.D. Allen M. Gown M.D. 《Survey of ophthalmology》1988,32(6):421-426
Intermediate filaments derived from different cell types are antigenically distinct. Monoclonal antibodies to human intermediate filament proteins can, therefore, be used as tissue-specific reagents capable of distinguishing cell type in poorly differentiated neoplasms. We report a case demonstrating the specificity of antiintermediate filament protein antibodies in establishing a difficult orbital diagnosis of esthesioneuroblastoma. 相似文献
83.
M. STEWARD R. BISHOP N.H. PIGGOTT I.D. MILTON B. ANGUS C.H.W. HORNE 《Histopathology》1997,30(1):16-22
Phenotypic analysis of lymphoproliferative disorders is now considered mandatory for accurate classification which is the basis for optimum patient management. This is presently carried out in most cases using a range of antibodies recognizing B and T-cell antigens effective in paraffin sections, and an antibody to CD3 is currently a key member of such panels, indicating T-cell phenotype. Current antibodies to CD3 are polyclonal with the inherent disadvantages of this type of reagent compared to monoclonal antibodies. In this study, we have used a recombinant fusion protein representing part of the epsilon subunit of the CD3 molecule to generate a novel monoclonal antibody (NCL-CD3-PS1) effective in paraffin sections. The antibody has been characterized biochemically and by immunohistochemistry using a wide range of normal and pathological tissues. Lineage and phenotype specificity have been supported in our study and results from other laboratories are awaited with interest. 相似文献
84.
Yoichi Kushima Tomonori Fujiwara Masumi Sanada Kimio Akagawa 《Journal of molecular neuroscience : MN》1997,8(1):19-27
We raised polyclonal and monoclonal antibodies against rat recombinant HPC-1/syntaxin 1A lacking a transmembrane domain. The
polyclonal antibody recognized two major bands at 35 and 40 kDa from rat brain membranes. A hybridoma clone designated 14D8,
however, recognized only one band at 35 kDa. A polyclonal antibody detected recombinant syntaxin 1B, as well as HPC-1/syntaxin
1A on an immunoblot, whereas 14D8 recognized recombinant HPC-1/syntaxin 1A, but not syntaxin 1B. Therefore, 14D8 is specific
for HPC-1/syntaxin 1A. Using this monoclonal antibody, we investigated the expression of HPC-1/syntaxin 1A in the rat hippocampal
membranes.
HPC-1/syntaxin 1A was present even in the embryonic d 19 (E19) hippocampal membranes, and it increased during the next two
postnatal wk. Pyramidal cell axons were intensely stained with the 14D8 monoclonal antibody, suggesting that HPC-1/syntaxin
1A was not restricted to the presynaptic terminal. Furthermore, we investigated the phosphorylation of HPC-1/syntaxin 1A in
the rat brain membranes. HPC-1/syntaxin 1A affinity-purified on a 14D8 IgG-coupled column was recognized by antiphophoserine
antibody, but not by antiphosphotyrosine and phosphothreonine antibodies. 相似文献
85.
目的 将人乳头瘤病毒16型(Human papillomavirus type 16,HPV-16)的晚期表达蛋白E7上的抗原24肽(从第38位氨基酸到第61位氨基6病毒感染防治酸)与人免疫球蛋白G的重链恒定区融合表达,并以此融合蛋白作为抗原,可能为HPV-1提供免疫治疗方法。方法 利用PCR方法分别扩增HPV-16 E7(38-61)24肽的DNA片段和人免疫球蛋白G的重链恒定区DNA片段,并构建到pEV21a表达载体上,转化入E.coli中表达,利用SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)和蛋白质免疫印迹(Western-blotting)的方法对表达结果进行鉴定。结果 构建的表达载体HPV16E7e/hIgGHCCR-pET21a经酶切鉴定和测序显示序列正确;通过SDS-PAGE和Western-blotting的鉴定,重组融合蛋白Mr约40000,表达量可占菌体蛋白的20%左右。结论 成功构建HPV16-E7的抗原多肽片段和人免疫球蛋白G的重链恒定区的融合蛋白,并可在E.coli中高效表达。 相似文献
86.
胰岛素样生长因子Ⅰ型受体单克隆抗体对结肠癌细胞生长的影响 总被引:2,自引:0,他引:2
目的探讨胰岛素样生长因子Ⅰ型受体(insulin-like growth factorⅠ receptor,IGF-ⅠR)在人结肠癌细胞株HT-29上的表达,以及两种胰岛素样生长因子Ⅰ型受体单克隆抗体(IGF-ⅠRMcAb)对HT-29细胞增殖的影响.方法免疫组织化学法检测HT-29的IGF-ⅠR表达,MTT法检测两种IGF-ⅠR McAb对HT-29的抑制增殖作用及诱导凋亡情况.结果人结肠癌细胞株HT-29细胞膜高表达IGF-ⅠR.IGF-ⅠR McAb能抑制HT-29细胞增殖,McAb对HT-29细胞的抑制作用随抗体浓度增大而增大.IGF-ⅠR McAb诱导HT-29凋亡,与对照组相比差异有统计学意义(P<0.01).结论IGF-ⅠR McAb通过阻断IGF-ⅠR抑制结肠癌细胞增殖、诱导细胞凋亡. 相似文献
87.
V. JNSSON H. D. SCHRDER W. TROJABORG T. STAEHELIN JENSEN E. HIPPE M. MRK HANSEN 《Journal of internal medicine》1992,232(2):185-191
A study of 17 patients with autoimmune axonal or demyelinating peripheral neuropathy in combination with M-component is described. The M-component was associated with MGUS (monoclonal gammopathy of undetermined significance) in 12 patients, CLL in one patient, WaldenstrÖm's disease in one patient, and myeloma in three patients. Immunohistological examination with direct and indirect fluorescence showed binding of antibodies to nerve structures of the same class and light chain as seen in the M-component. In five cases of IgM M-component, the demyelinating neuropathy was caused by binding of the IgM M-protein and complement C3b to myelin-associated glycoproteins (MAG). In 12 cases with axonal neuropathy, binding of IgG to the connective tissue of the peri- and endoneurium was found in 50% of cases, IgM in five cases, and IgD in one case. None of the patients had central nervous system (CNS) symptoms. The clinical and therapeutic difficulties are discussed; only two patients with an acute course responded to immunosuppression. A marked co-expression of other autoimmune phenomena is interpreted in the light of cross-reactions between the autoantibody and similar tissue autoantigens. 相似文献
88.
89.
从蝮蛇毒中提取磷酸二酯酶,用此酶免疫BALB/c小鼠,取其脾细胞与小鼠骨髓瘤细胞Fo融合,以间接ELISA检测杂交瘤细胞培养上清液和小鼠腹水中的特异性抗体,其效价分别为1∶128和1∶51 200.抗原阻断试验结果表明,此抗体对蛇毒磷酸二酯酶具有特异性.该杂交瘤细胞株定为G_8,该株单抗属鼠IgG_(2a)亚型,经体外持续培养6个月,其分泌抗体性能稳定. 相似文献
90.
胃癌单克隆抗体-丝裂霉素C结合物的制备及其细胞毒特征 总被引:1,自引:1,他引:0
作者报道胃癌单克隆抗体MG11-丝裂霉素C(MMC)结合物的制备及其对肿瘤细胞的杀伤作用。首先用戊二酐处理MMC,于MMC上引入羧基,MMC衍生物与N羟基琥珀酰亚胺及2,2′-二环已基碳二亚胺反应,得到MMC活性酯,后者与抗体反应将MMC引入抗体中。经测定,每克分子抗体中引入约6~7克分子药物,结合物对人胃癌细胞KATⅢ具有较强的选择性杀伤作用,在0.56μg/ml水平(药物浓度)对肿瘤细胞杀伤牢达60%,优于游离药物(51%)及无关抗体结合物(9.3%),提示选用的胃癌单抗对MMC具有较好的导向作用。 相似文献