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151.
近年来 ,脑功能成像技术发展迅速 ,已在脑科学研究中占有重要地位。研究中通常需要将同一被试的多种模式成像结果或同一模式的时间序列结果结合起来分析 ,首先要解决的问题就是几幅图像的严格对齐问题 ,即所谓的图像配准。在模拟退火算法和其它工作的基础之上 ,较好的解决了图像配准中的连续变量全局优化问题 ,通过基于点的配准方法 ,实现了时间序列脑功能图像的高精度配准。 相似文献
152.
Decidualization is a critical step during embryo implantation that is characterized by the differentiation of endometrial stromal cells (ESC) into decidua cells. However, the mechanism of differentiation remains largely unknown. Previously, it has been shown that the null function of homeo box A10 (HOXA10) causes defects in both implantation and decidualization, suggesting that the HOXA10 signalling pathway is likely to be involved in uterine decidualization. In the present study, we determined the expression and subcellular distribution of HOXA10 and its downstream molecule, p57, in ESC during in vitro decidualization induced by a combination of 8-bromo-cAMP and medroxyprogesterone acetate. We demonstrated that the HOXA10 was down-regulated while in contrast, p57 was up-regulated in the process of decidualization. Immunocytochemistry and transient expression of the HOXA10 tagged with green fluorescence protein revealed that there were no differences in the HOXA10 subcellular localization between the induced and non-induced ESC. Our results suggest that the down-regulation of HOXA10 may contribute to increased p57 and that up-regulation of p57 likely plays an important role in ESC differentiation in the process of decidualization. The progesterone receptor pathway may participate in promoting ESC to exit the cell cycle and enter differentiation. 相似文献
153.
An increasing demand for polycistronic vectors that express multiple genes simultaneously has arisen in recent years to obtain an efficient gene therapy. Armed with the knowledge that the expression of transgene in mammalian cells often requires tight control, we constructed in this study a tetracycline-regulated double-gene adeno-associated virus (AAV) vector carrying green and red fluorescent protein genes and expressed it in PC12 cells. When detected by fluorescence microscope and fluorescence-activated cell sorting, gene expression was induced by 44-66-fold and could be reversibly controlled by doxycycline. This double-gene AAV vector may be useful for regulated expression of two genes or a marker to monitor transgene expression. 相似文献
154.
高强度聚焦超声在医学领域中应用的新进展 总被引:1,自引:0,他引:1
本文综述了国内外在高强度聚焦超声(high intensity focused ultrasound,HIFU)技术方面研究与应用的新进展。介绍了HIFU的治疗功能原理,特别给出了焦斑半径的具体计算公式和对相关组织的热效应、空化效应、机械效应,辐照效应等损伤机理,重点研究了热效应随声波频率及声强变化的规律。给出了HIFU的一般试验模型即分层组织模型以及HIFU应用与临床的情况。重点研究了HIFU源,主要讨论了换能器的聚焦方式(1)球面自聚焦换能器,(2)声透镜聚焦换能器,(3)大功率多元超声换能器,(4)电子扫描或相控阵列聚焦换能器,以及频率选择与目标深度和辐照强度的关系,并指出与其匹配的几类聚焦换能器的优缺点,列举了HIFU技术在泌尿科、肿瘤学、神经外科、眼科、妇科、止血以及其他医学领域中的最新应用。最后评价了目前HIFU在治疗方面的优势与某些不足以及可能改进的有效措施.展望了HIFU技术广阔的应用前景. 相似文献
155.
Epithelial-myoepithelial tumor is extremely rare as a pulmonary neoplasm. Only 20 cases have been reported to date, of which 14 were malignant. We report a case of intrabronchial epithelial-myoepithelial carcinoma in a 73-year-old man with a history of heavy smoking. The tumor was well-circumscribed and caused distal airway obstruction. Histologically, the tumor showed glandular and solid architecture. The glands were composed of an inner layer of epithelial cells and an outer layer of myoepithelial cells. The solid areas consisted of spindle-shaped myoepithelial cells. Immunohistochemical staining was positive for p53 and c-Kit (CD117). Focal atypia and increased mitotic activity were present, but no vascular invasion or nodal metastasis was identified. 相似文献
156.
胃癌 (Gastric Cancer,GC) 是全球第五大最常见的恶性肿瘤,也是第四大癌症死亡相关原因。胃癌异质性明显,肿瘤微环境复杂,免疫检查点抑制剂虽然在晚期胃癌中展现出一定抗肿瘤疗效,但获益人群仍在少数。吲哚胺2,3-双加氧酶 1 (Indoleamine 2,3-Dioxygenase 1,IDO1) 是色氨酸沿犬尿氨酸途径代谢中的关键酶,对肿瘤免疫逃逸起到了关键作用。目前已有多项研究表明IDO1在胃癌发生发展及幽门螺杆菌感染和EB病毒感染中发挥重要作用,所以靶向IDO1有望成为胃癌免疫治疗的新策略。本文就IDO1作用机制、IDO1在胃癌及相关疾病中的研究进展及IDO1抑制剂在胃癌中的应用前景进行综述。 相似文献
157.
抗磺胺嘧啶单克隆抗体的制备及其ELISA检测试剂盒的建立 总被引:16,自引:1,他引:16
目的 :制备抗磺胺嘧啶 (SD)的单克隆抗体 (mAb) ,并研制SD快速检测试剂盒。方法 :以SD BSA的偶联物作为抗原免疫BALB/c小鼠 ,采用杂交瘤技术制备抗SD的mAb。并用抗SDmAb和SD HRP酶标抗原 ,建立一种可检测样品中的游离SD分子的竞争法ELISA。结果 :获得 5株可分泌抗SDmAb的杂交瘤细胞 1A1、1B8、1E4、2C1和 3D9。其中 1A1、1B8和 1E4为IgG1,2C1和 3D9为IgG2。试剂盒的半数抑制率 (I5 0 )为 9.3μg/L ,理论最低检出量达到 0 .6μg/L ,对于不同样品中SD的回收率均高于 60 %。除与SD反应以外 ,该试剂盒对其他磺胺类药物检测的交叉反应均小于 3 %。结论 :成功地制备了抗SD的mAb ,并建立了一种可快速检测各种样品中SD的竞争ELISA试剂盒 相似文献
158.
Xia J Deng H Feng Y Zhang H Pan Q Dai H Long Z Tang B Deng H Chen Y Zhang R Zheng D He Y Xia K 《Journal of human genetics》2002,47(12):0635-0640
Hearing impairment is an extremely heterogeneous disorder. A total of 35 loci and 17 related genes for autosomal dominant
nonsyndromic hearing loss have been identified. In a Chinese pedigree characterized by autosomal dominant inheritance with
bilateral, postlingual, progressive, and sensorineural nonsyndromic hearing impairment, the putative disease gene locus was
localized to chromosome 5q31.1-32 by a genome-wide scan. Fine mapping indicated that the disease gene was located within an
8.8-cM region between markers D5S2056 and D5S638, with a maximum two-point logarithm of differences (LOD) score of 6.89 (θ = 0) at D5S2017. By the candidate gene approach, mutation screening of the DIAPH1 and POU4F3 genes at 5q31 was performed. No mutation was found, suggesting that this is a novel deafness locus, which has been named
DFNA42.
Received: May 8, 2002 / Accepted: October 1, 2002 相似文献
159.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
160.
Lin Hui Eun-Seok Shin Eun Jung Jun Youngjune Bhak Scot Garg Tae-Hyun Kim Chang-Bae Sohn Byung Joo Choi Liu Kun Song Lin Yuan Wang Zhi Jiang Hao Shi Zhentao Tang Qiang 《Yonsei medical journal》2020,61(12):1004
PurposeDissection after plain balloon angioplasty is required to achieve adequate luminal area; however, it is associated with a high risk of vascular events. This study aimed to examine the relationship between non-flow limiting coronary dissections and subsequent lumen loss and long-term clinical outcomes following successful drug-coated balloon (DCB) treatment of de novo coronary lesions.Materials and MethodsA total of 227 patients with good distal flow (Thrombolysis in Myocardial Infarction flow grade 3) following DCB treatment were retrospectively enrolled and stratified according to the presence or absence of a non-flow limiting dissection. The primary endpoint was late lumen loss (LLL) at 6-month angiography, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization, and target vessel thrombosis).ResultsThe cohort consisted of 95 patients with and 132 patients without a dissection. There were no between-group differences in LLL (90.8%) returning for angiography at 6 months (0.05±0.19 mm in non-dissection and 0.05±0.30 mm in dissection group, p=0.886) or in TVF (6.8% in non-dissection and 8.4% in dissection group, p=0.799) at a median follow-up of 3.4 years. In a multivariate analysis, the presence of dissection and its severity were not associated with LLL or TVF. Almost dissections (93.9%) were completely healed, and there was no newly developed dissection at 6-month angiography.ConclusionThe presence of a dissection following successful DCB treatment of a de novo coronary lesion may not be associated with an increased risk of LLL or TVF (Impact of Drug-coated Balloon Treatment in de Novo Coronary Lesion; ). NCT04619277相似文献