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101.
102.
The prevalence of malignant transformation of endometriotic lesions is estimated between 0.3% and 1%. Malignant transformations of endometriosis occur in the colorectum is rarer, accounting for 0.25%. Because the malignant transformation of colorectal endometriosis rarely involves mucosa, it is difficult to obtain abnormal tissue by routine endoscopic biopsy. In this case, we evaluated a patient with a rectal mass by endorectal ultrasound (ERUS) and performed endorectal ultrasound-guided biopsy (EGB). Malignant transformations of endometriosis were confirmed by histological result. For patients with rectal tumors but with negative findings on colonoscopy and biopsy, ERUS and EGB contribute to preoperative diagnosis.  相似文献   
103.
目的探讨骨髓增生异常综合征(myelodysplastic syndromes,MDS)患者ASXL1基因变异的发生情况及其与其他基因变异和部分临床参数之间的相关性。方法采用PCR扩增产物直接测序法检测149例MDS患者ASXU、U2AF1、SF3B1、DNMT3A、TET2、IDH1/2、NPM1、FLT3-ITD.C-KIT等基因的变异情况。结果在149例患者中,ASXU基因变异的检出率为24.8%(37/149),变异率>5%的基因分别是U2AF1(22.8%)、TET2(11.4%)、DNMT3A(9.4%)、NPM1(8.1%).SF3B1(6.0%)。ASXL1变异最常见的共存变异基因为U2AF1(27.0%,10/37)及TET2(18.9%,7/37)。ASXL1变异组与野生组患者在中位年龄、MDS亚型、染色体核型、外周白细胞、血红蛋白、血小板水平及骨髓原始细胞计数等方面的差异均无统计学意义(P>0.05)o对29例ASXL1变异患者进行了有效的随访,其中11例进展为急性髓系白血病(acute myeloid leukemia,AML),白血病转化率为37.9%。在92例野生型患者中,13例进展为AML,白血病转化率为14.1%。ASXL1变异组白血病转化率明显高于野生组,差异有统计学意义(PV 0.01)。结论ASXL1变异在MDS中有较高的发生率,并常与U2AF1及TET2基因变异共存,伴有该变异的患者具有更高的白血病转化率。  相似文献   
104.
The lysosomal cysteine carboxypeptidase cathepsin X (CTSX), localized predominantly in immune cells, has been associated with the development and progression of cancer. To determine its specific role in colorectal carcinoma (CRC), we analyzed CTSX expression in non-malignant mucosa and carcinoma of 177 patients as well as in 111 adenomas and related it with clinicopathological parameters. Further, the role of CTSX in the adhesion and invasion of the colon carcinoma cell lines HT-29 and HCT116 was investigated in an in vitro culture cell system with fibroblasts and monocytes, reflecting the situation at the tumor invasion front.Epithelial CTSX expression significantly increased from normal mucosa to adenoma and carcinoma, with highest expression levels in high grade intraepithelial neoplasia and in early tumor stages. Loss of CTSX occurred with tumor progression, and correlated with advanced local invasion, lymph node and distal metastasis, lymphatic vessel and vein invasion, tumor cell budding and poorer overall survival of patients with CRC. The subcellular distribution of CTSX changed from vesicular paranuclear expression in the tumor center to submembranous expression in cells of the invasion front. Peritumoral macrophages showed highest expression of CTSX. In vitro assays identified CTSX as relevant factor for cell–cell adhesion and tumor cell anchorage to fibroblasts and basal membrane components, whereas inhibition of CTSX caused increased invasiveness of colon carcinoma cells in mono- and co-culture. In conclusion, CTSX is involved in early tumorigenesis and in the stabilization of tumor cell formation in CRC. The results suggest that loss of CTSX may be needed for tumor cell detachment, local invasion and tumor progression. In addition, CTSX in tumor-associated macrophages indicates a role for CTSX in the anti-tumor immune response.  相似文献   
105.
106.
We present a patient with a 33‐year history of poikilodermatous mycosis fungoides (MF) who subsequently developed CD30‐positive large cell transformation. After 6 years of conventional MF treatment, side effects of therapy and/or concomitant diseases prevented the previously applied treatment modalities. The CD30‐directed antibody‐cytotoxic drug conjugate (brentuximab vedotin) was introduced and followed by quick and excellent therapeutic response.  相似文献   
107.
Goal-directed movements involve a series of neural computations that compare the sensory representations of goal location and effector position, and transform these into motor commands. Neurons in posterior parietal cortex (PPC) control several effectors (e.g., eye, hand, foot) and encode goal location in a variety of spatial coordinate systems, including those anchored to gaze direction, and to the positions of the head, shoulder, or hand. However, there is little evidence on whether reference frames depend also on the effector and/or type of motor response. We addressed this issue in macaque PPC area V6A, where previous reports using a fixate-to-reach in depth task, from different starting arm positions, indicated that most units use mixed body/hand-centered coordinates. Here, we applied singular value decomposition and gradient analyses to characterize the reference frames in V6A while the animals, instead of arm reaching, performed a nonspatial motor response (hand lift). We found that most neurons used mixed body/hand coordinates, instead of “pure” body-, or hand-centered coordinates. During the task progress the effect of hand position on activity became stronger compared to target location. Activity consistent with body-centered coding was present only in a subset of neurons active early in the task. Applying the same analyses to a population of V6A neurons recorded during the fixate-to-reach task yielded similar results. These findings suggest that V6A neurons use consistent reference frames between spatial and nonspatial motor responses, a functional property that may allow the integration of spatial awareness and movement control.  相似文献   
108.
Human T-cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus that is the causative infectious agent of adult T-cell leukemia/lymphoma (ATL), an aggressive and fatal CD4+ T-cell malignancy, and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic neurological disease. Disease progression in infected individuals is the result of HTLV-1-driven clonal expansion of CD4+ T-cells and is generally associated with the activities of the viral oncoproteins Tax and Hbz. A closely related virus, HTLV-2, exhibits similar genomic features and the capacity to transform T-cells, but is non-pathogenic. In vitro, HTLV-1 primarily immortalizes or transforms CD4+ T-cells, while HTLV-2 displays a transformation tropism for CD8+ T-cells. This distinct tropism is recapitulated in infected people. Through comparative studies, the genetic determinant for this divergent tropism of HTLV-1/2 has been mapped to the viral envelope (Env). In this review, we explore the emerging roles for Env beyond initial viral entry and examine current perspectives on its contributions to HTLV-1-mediated disease development.  相似文献   
109.
目的探究mCD99L2基因沉默对小鼠B淋巴瘤细胞系A20细胞转化为H/RS样细胞的影响。方法重组SiRNA表达质粒LV-mCD99L2,体外转染内源性mCD99L2表达阳性的A20细胞,筛选出稳定表达LV质粒的细胞株并扩增培养;采用免疫荧光技术和流式细胞仪检测转化前后两组细胞鼠源CD30表达;透射电镜观察转化后细胞超微结构的形态特点;细胞计数方法动态观测培养细胞干扰组A20-LV-mCD99L2和未经干扰组A20细胞的H/RS样细胞(直径≥25μm)转型率,以人霍奇金淋巴瘤细胞系L428作为对照;采用流式细胞仪检测细胞周期变化。结果获得了稳定表达LV质粒的单克隆细胞株A20-LV-mCD99L2;免疫荧光标记显示转化细胞CD30( );流式细胞仪检测A20-LV-mCD99L2细胞CD30阳性率为54.4%;透射电镜观察转化后细胞核增大,可见单核、双核及多核,核仁明显的H/RS样细胞;干扰组H/RS样细胞的转型率明显高于未经干扰组(P<0.01)。两组处于S期的细胞无明显差异,两组细胞均未见凋亡峰。结论mCD99L2基因沉默可诱导小鼠B淋巴瘤细胞系A20细胞转化为H/RS样细胞。  相似文献   
110.
脑梗死后出血性转化的研究进展   总被引:6,自引:1,他引:6  
本文综述了脑梗死后出血性转化的类型和预后以及可能的机制,并讨论了溶栓剂组织型纤溶酶原激活物(t-PA)对脑梗死后出血性转化的影响以及出血性转化的干预措施,为脑梗死的临床治疗和研究提供参考。  相似文献   
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