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51.
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   
52.
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   
53.
以四川地区1例无症状携带丁型肝炎病毒(HDV)和乙型肝炎病毒(HBV)患者的外周血为标本,采用逆转录-PCR技术,获得了HDV全基因组的cDNA克隆(HDVSZ93株),全长1684bp。与世界其他七个地区株相比,其核酸同源性为81.8%~95.4%;丁肝病毒抗原蛋白编码区核酸同源性为88.9%~96.1%,氨基酸同源性为86,4%~93.0%。另从1例慢性重型肝炎患者血清内克隆了丁肝病毒抗原蛋白(HDAg)编码基因(HDV-SZ92株),与SZ93株相比,亦存在若干变异。对这些不同地区、不同病情HDV株变异的可能意义进行了讨论。  相似文献   
54.
Extracorporeal immune adsorption with staphylococcal protein A (SPA) columns can remove immune complexes and immunoglobulins in the treatment of a variety of diseases. We present the case of an elderly man with neuropathy associated with monoclonal gammopathy, treated by 3 on-line SPA procedures. At the completion of these treatments his neuropathy relapsed, progressing to near-total paralysis. Return to a baseline clinical status required several months. The reason for this severe relapse is not clear. Possible explanations include SPA activation of T-lymphocytes, with release of gamma interferon and increased antigen recognition, or removal of an anti-idiotype control mechanism. We advise caution in the application of immunoadsorption to conditions in which it has not yet been evaluated. © 1992 Wiley-Liss, Inc.  相似文献   
55.
Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed.  相似文献   
56.
报告了应用单克隆抗体对25例淋巴细胞白血病、5例慢性粒细胞白血病及15例急性非淋巴细胞白血病进行免疫分型并与AB分型作比较,结果提示免疫分型可以弥补FAB分型的不足,它有助于白血病临床诊断、鉴别诊断、指导治疗和判断预后。  相似文献   
57.
The murine monoclonal antibody, LH39 was characterized in this study and appeared to bind to a novel basement membrane epitope. This antigen was expressed in the epithelial basement membrane of human tissue derived from all three germ cell layers and in basement membranes surrounding small blood vessels within the stroma of all organs examined. LH39 antigen could be first detected in fetal skin at the dermo-epidermal junction at 7 weeks estimated gestational age but was not present in the dermal vasculature until 16 weeks. When tested against tissue from a range of lower mammalian species, LH39 antigen appeared to be primate-specific. The epithelial basement membrane zone in organotypical cultures, where there is de novo synthesis of basement membrane components, contained abundant LH39 antigen in contrast to other basement membrane components, type IV collagen, laminin, and type VII collagen. Ultrastructural localization of LH39 epitope, using immunogold electron microscopy on unfixed freshly frozen tissue, was to the lamina lucida. No cross-reactivity could be detected between LH39 and laminin, fibronectin, and collagens I, III, IV, and V using the ELISA assay. In vitro studies with a range of proteolytic enzymes suggested that the antigen was non-collagenous in nature. LH39 precipitated a polypeptide with a molecular weight of 185 kD from extracts of metabolically labelled cultured keratinocytes, and polypeptides of 185 and 200 kD from the culture medium. The tissue distribution of LH39 antigen suggested that it may be an epitope within anchoring filaments. Potential applications of this antibody include the study of benign and malignant human vascular disorders, diseases and tumours associated with angiogenesis, epithelial neoplasms, and conditions of tissue regeneration and repair, such as wound healing.  相似文献   
58.
SJL/J mice challenged with myelin basic protein (MBP) in complete Freund's adjuvant (CFA) developed only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence. However, treatment of challenged mice with anti-infeferonγ (IFN-γ) monoclonal antibody (mAb) determined severe disease in all cases. Similarly, in passive EAE, the addition of anti-IFN-γ to the in vitro MBP-activated cells at the time of transfer led to significant disease exacerbation in all recipients. The disease enhancing effect was observed only when the mAb was given at the time of active challenge or of passive transfer, but not at later times. Anti-interleukin-2 (IL-2) antibody had only a marginal effect in the active induction, but drastically reduced the manifestations of passive EAE, even when mixed with a disease-enhancing dose of anti-IFN-γ. These findings support the notion that IL-2 is required for disease induction whereas IFN-γ plays a disease-limiting role early in the development of EAE.  相似文献   
59.
Current concepts on monoclonal gammopathies   总被引:1,自引:0,他引:1  
This is a review of the monoclonal gammopathies, including a discussion of cause. The role of T lymphocytes and B lymphocytes is presented. The recognition of a monoclonal protein in the serum and urine is presented in detail.
The frequency of benign and malignant monoclonal gammopathies is provided. A long-term follow-up of 241 patients with apparently benign monoclonal gammopathy is examined closely. In this series, multiple myeloma, macroglobulinaemia, amyloidosis, or related disorders developed in 22% of the 241 patients with long-term disease. The median duration from the recognition of the monoclonal protein until the development of serious disease was approximately eight to ten years.
The differentiation of benign from malignant monoclonal gammopathics is examinad in detail. The point is made that paticnu must be folld indefinitely because malignancy may develop more than 20 years later. The association of monoclonal gammopathies with other apparently unrelated diseases discussed. (Aust NZ J Med 1992; 22: 291–302.)  相似文献   
60.
目的分离、培养和鉴定正常人肾小球系膜细胞。方法筛网滤过分离正常人肾小球系膜细胞,同时采用免疫荧光技术,利用异硫氰酸荧光素(FITC)间接标记单克隆抗体:抗Ⅷ因子相关抗原抗体、抗结蛋白抗体、抗角蛋白抗体、抗细胞角蛋白抗体、抗Ⅳ型胶原抗体、抗纤维连接蛋白抗体、抗层粘连蛋白抗体对系膜细胞特有的中间微丝进行鉴定。并采用同期培养的同一来源的肾小球内皮细胞作对照。结果抗Ⅷ因子相关抗原、抗角蛋白和抗细胞角蛋白抗体表达均为阴性,而抗结蛋白抗体、抗Ⅳ型胶原抗体、抗纤维连接蛋白抗体、抗层粘连蛋白抗体为阳性,说明培养的细胞为系膜细胞。结论该种方法分离培养的细胞经过免疫荧光染色鉴定为肾小球系膜细胞。  相似文献   
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