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191.
人膀胱癌T24细胞及其SCID小鼠移植瘤组织中KDR的表达 总被引:1,自引:1,他引:0
目的 检测KDR在人膀胱癌T24细胞及其SCID小鼠移植瘤组织中的表达。方法 常规培养T24细胞,建立荷人膀胱癌移植瘤SCID小鼠动物模型,使用抗KDR单克隆抗体,通过免疫荧光、免疫组化检测KDR在T24细胞及瘤体组织上的表达;结果 KDR在T24细胞及瘤体组织中均呈阳性表达。结论 本研究结果为进一步研究抗KDR单抗在荷T24细胞移植瘤动物体内分布及对瘤体生长的抑制效应奠定了实验基础。 相似文献
192.
Bacterial components regulate the expression of Toll-like receptor 4 on human mast cells 总被引:3,自引:0,他引:3
Y. Kubo N. Fukuishi M. Yoshioka Y. Kawasoe S. Iriguchi N. Imajo Y. Yasui N. Matsui M. Akagi 《Inflammation research》2007,56(2):70-75
Objectives and design: The aim of this study was to investigate whether the exposure of mast cells (MCs) to bacterial components affects the expression
of Toll-like receptor (TLR) 4, and to elucidate the behavior of MCs during the early response to infection.
Materials: Two human MC lines, HMC-1 and LAD2, were employed. Messenger RNA expression was observed by RT and real-time PCR. TLR4 expression
was determined by Western blotting. TNF-α secretion was analyzed with ELISA. The degranulation ratio was measured with betahexosaminidase
assay.
Results: Although bacterial components increased TLR4 mRNA, only lipopolysaccharide (LPS) augmented the TLR4 protein expression. LAD2
pre-treated with LPS for 8 h resulted in 2-fold increased TNF-α secretion on LPS restimulation.
Conclusion: These results suggest that the exposure of MCs to LPS may reinforce the innate immune system due to up-regulation of MC TLR4,
followed by increased TNF-α release.
Received 20 April 2006; returned for revision 14 July 2006; accepted by G. Wallace 11 August 2006 相似文献
193.
抗肝癌单链双功能抗体在Hut-78细胞系中的表达及体外杀伤活性 总被引:1,自引:0,他引:1
目的 用携带分泌型抗肝癌单链双功能抗体基因(sFv-TNF-α)的重组逆转录病毒感染T细胞淋巴瘤Hut-78细胞,使其表达并分泌针对人肝癌细胞的sFv-TNF-α融合蛋白,观察转导的T细胞对体外培养肝癌细胞的杀伤作用。方法 用感染性重组病毒产生细胞C22(PA317/PST)产生的病毒上清转导入T细胞淋巴瘤Hut-78细胞,采用PCR,RT-PCR,细胞原位杂交及免疫组织化学染色等方法,对转导的Hut-78细胞进行DNA,mRNA及蛋白水平的分析。转导的Hut-78细胞分别与SMMC-7721,HHCC共培养,MTT法检测Hut/PST细胞表达产物对两种肝癌细胞的杀伤作用。结果 PCR,RT-PCR结果显示转导Hut细胞中扩增出外源目的基因对应的电泳条带,neo基因探针原位杂交显示转导细胞质内有较强的紫蓝色阳性反应信号,其阳性率约为95%,鼠抗人TNF-α多克隆抗体免疫组织化学染色,转导细胞质内有明确的棕黄色阳性反应信号,MTT法检测结果,分泌型抗肝癌单链双功能抗体对体外培养的两种肝癌细胞的杀伤率分别为15.4%和26.5%。结论 分泌型抗肝癌单链双功能抗体基因可以在T细胞中整合并稳定表达,其分泌的表达产物对两种肝癌细胞均具有一定的亲合活性,并且具有一定的体外杀伤作用。 相似文献
194.
螺旋藻多糖对人宫颈癌Hela细胞体外生长的影响 总被引:6,自引:1,他引:5
目的:探讨螺旋藻多糖(PSP)对体外培养的Hela细胞生长的影响。方法:采用MTT法测定 PSP的抗肿瘤活性,并观察其对Hela细胞形态学的影响。结果:随PSP浓度的升高,Hela细胞存活率逐渐降低,抑制率逐渐增加;光镜下观察显示,PSP作用24-48h后,细胞出现明显的形态学改变。结论:PSP能抑制Hela细胞增殖。 相似文献
195.
I. HELIN A. WIDELL S. BORULF M. WALDER U. ULMSTEN 《Acta paediatrica (Oslo, Norway : 1992)》1987,76(2):234-238
ABSTRACT. During the late winter of 1983, 16 newborns with vague symptoms of failure to thrive, reluctance to feed and a slight rise in body temperature, were found to have meningitis caused by Coxsackievirus A-14. The cerebrospinal fluid showed pleocytosis with polymorphonuclear cells in excess but was otherwise normal. The clinical course was uneventful in all infants, but two of them demonstrated clinical signs of incipient cerebral oedema during the acute phase of the illness. An electroencephalogram (EEG) during the initial course of the disease and at nine months of age was normal in all. During a follow-up period of 21/2 years they all developed normally and no sequelae were noted. The presentation also demonstrates the usefulness of Vero cells for the propagation of the responsible virus. 相似文献
196.
N. E. McCarthy H. A. Jones N. A. Marks R. J. Shiner P. W. Ind H. O. Al-Hassi N. R. English C. M. Murray J. R. Lambert S. C. Knight A. J. Stagg 《Clinical and experimental allergy》2007,37(1):72-82
Background Dendritic cells (DC) mediate inflammation in rodent models of allergic airway disease, but the role played by human respiratory‐tract DC (hRTDC) in atopic asthma remains poorly defined. Recent data suggest that CD1 antigen presentation by hRTDC may contribute to asthma pathogenesis. Objective To investigate the influence of hRTDC on the balance between atopy and allergic asthma in human subjects and to determine whether CD1 expression by hRTDC is modulated during asthmatic inflammation. Methods Sputum cells were induced from steroid‐naïve, allergen‐challenged and allergen‐naïve subjects (atopic asthmatics, atopic non‐asthmatics and non‐atopic controls). hRTDC were identified using monoclonal antibody labelling and analysis by flow cytometry. Results hRTDC stained HLA‐DR+ (negative for markers of other cell lineages) were predominantly myeloid and comprised ∼0.5% of viable sputum cells. Sputum cells were potent stimulators of allogeneic CD4+ naïve T cells and enrichment/depletion experiments correlated stimulatory potency with DC numbers. Sputum contained cells that exhibited typical dendritic morphology when analysed by electron microscopy. Myeloid hRTDC were endocytically active, but uptake of FITC‐dextran was enhanced in cells from asthmatics (P<0.001). Despite their increased endocytic capacity, asthmatic myeloid hRTDC appeared mature and expressed increased levels of maturation markers (P<0.05–P<0.001), CD1c, CD1d and langerin (P<0.05). CD1c expression by asthmatic myeloid hRTDC was enhanced upon in vivo allergen challenge (three to ninefold within 24 h; P<0.05). CD11c−CD123high hRTDC were only detected in asthmatic sputum and were increased in number following allergen challenge. Conclusion Despite limited cell numbers, it proved possible to analyse human RTDC in induced sputum, providing evidence that increased antigen uptake and enhanced CD1 presentation by activated hRTDC may contribute to allergic airway disease. CD1 presentation by hRTDC in atopic asthma may therefore constitute a novel target for future intervention strategies. 相似文献
197.
Egon Marth 《Archives of toxicology》1987,60(4):293-299
Mice were exposed to very small quantities of Per (0.05 and 0.1 mg Per/kg body weight per day) administered orally for 7 weeks. It was shown that Per was transported through the body by two separate mechanisms and was finally stored in the adipose tissue. On the one hand, Per reaches the interior of the membranes of red blood cells, leading to changes in the entire erythropoietic system. The membranes of the red blood cells are destroyed prematurely and its fragments are increasingly phagocytized in the spleen. The result is a high level of Per stored in the spleen. The increase in haemolysis was also demonstrated by showing an increase in LDH activity and the accumulation of haemosiderin in the macrophages in the spleen. Only 8 weeks following discontinuation of Per, these changes were reversible. On the other hand, Per is also transported with the chylomicrons. Since the lipoprotein lipase is inhibited by Per, these molecules are broken down to a lesser degree. The concentration of triglycerides (the major component of the chylomicrons) in the serum was elevated, and the chylomicrons were increasingly integrated into the adipose tissue, Per also reached this depot fat. It took as long as 16 weeks after discontinuation of Per until these changes were fully reversed and the experimental mice no longer differed from those in the control group.Abbreviations Per
Perchloroethylene (1,1,2,2-tetrachloroethylene)
- SGPT
serum glutamate-pyruvate-transaminase
- TCA
trichloroacetic acid
- TCE
trichloroethanol
- NAD
nicotinamide adenine dinucleotide
- PBS
phosphate buffered saline
- LDH
lactate dehydrogenase
- LDL
low density lipoproteins
- VLDL
very low density lipoproteins 相似文献
198.
Emilie Balasse Gregory Gatouillat Dominique Patigny Marie Christine Andry Claudie Madoulet 《Vaccine》2009
Malignant melanoma causes significant health problems. The identification of tumour-associated antigens has led to novel approaches to increase T cell mediated anti-tumour immune response. Melan-A/MART-1 has been use as target antigen for several T cell based immunotherapeutic treatments. More recently, the critical role of CD4+ T cells in inducing and maintaining anti-tumour immunity has been increasingly recognized. In order to optimize tumour immunotherapy, greater efforts have been concentrated on the identification of tumour antigens presented by MHC class II molecules to CD4+ T cells. In a publication, Tiwari et al. (2004) [1] have identified by a computational approach the 15-mer amino-acid sequence 101–115 (PPAYEKLSAEQSPPP) of the Melan-A/MART-1 as a good target for a vigorous and safe immunotherapy. Therefore, we have investigated the in vivo anti-tumour activity of this peptide in a murine melanoma model. For the prophylactic treatment, 20 μg or 50 μg peptide was subcutaneously injected in mice once a week during 3 weeks before tumour induction. Treatment with 50 μg peptide significantly affected tumour development. Thus, our preliminary data demonstrate potential in vivo prophylactic activity of the 101–115 peptide-based vaccine to control melanoma growth. 相似文献
199.
Acute Cellular Rejection with CD20-Positive Lymphoid Clusters in Kidney Transplant Patients Following Lymphocyte Depletion 总被引:1,自引:0,他引:1
L. K. Kayler F. G. Lakkis C. Morgan A. Basu D. Blisard H. P. Tan J. McCauley C. Wu R. Shapiro P. S. Randhawa 《American journal of transplantation》2007,7(4):949-954
Lymphoid clusters (LC) containing CD20-positive B cells in kidney allografts undergoing acute cellular rejection (ACR) have been identified in small studies as a prognostic factor for glucocorticoid resistance and graft loss. Allograft biopsies obtained during the first episode of ACR in 120 recipients were evaluated for LC, immunostained with CD20 antibody, and correlated with conventional histopathologic criteria, response to treatment and outcome. LC were found in 71 (59%) of the 120 biopsies. All contained CD20 positive B cells that accounted for 5-90% of the LC leukocyte content. The incidence of LC was highest in the patients who had no lymphoid depletion or had been treated with Thymoglobulin preconditioning (79% vs. 75%, respectively) compared to 37% in patients pretreated with Campath (p = 0.0001). Banff 1a/1b ACR were more frequent in the LC-positive than the LC-negative group (96% vs. 80%, respectively; p = 0.0051). With a posttransplant follow-up of 953 +/- 430 days, no significant differences were detected between LC-postitive and LC-negative groups in time to ACR, steroid resistance, serum creatinine and graft loss. CD20+LC did not portend glucocorticoid resistance or worse short to medium term outcomes. CD20+LC may represent a heterogenous collection in which there may be a small still to be fully defined unfavorable subgroup. 相似文献
200.
目的 了解不同组织来源癌细胞株和人体肿瘤组织原代细胞的DNA双链断裂损伤修复的个体差异性,探寻预测癌细胞辐射敏感性的生物指标。方法 60Co γ射线照射诱发DNA损伤,脉冲电场凝胶电泳检测DNA双链断裂损伤修复,细胞克隆形成能力法检测细胞辐射敏感性。结果 8个不同组织来源癌细胞株的辐射敏感性有较大的差异(D0为0.65~2.15 Gy),不同细胞株20 Gy γ射线照射诱发产生的DNA双链断裂原初损伤有一定的差别,但与细胞辐射抗性无相关性。辐射敏感细胞SX-10的DNA双链断裂修复缺陷发生在早期快速修复相,而A2780细胞的修复缺陷是发生在晚期慢速修复相。20 Gy照射修复2 h后DNA双链断裂残留量与细胞辐射敏感性指标D0或SF2值有显著的相关性。不同个体患者脑肿瘤组织原代细胞之间,辐射诱发DNA双链断裂的修复反应存在明显差异,修复2 h后残留损伤的个体差异性分布类似于癌细胞株。结论 DNA双链断裂残留损伤与癌细胞辐射抗性有显著相关性,可作生物指标预测肿瘤组织细胞对放射治疗的反应性。 相似文献