全文获取类型
收费全文 | 13054篇 |
免费 | 1065篇 |
国内免费 | 330篇 |
专业分类
耳鼻咽喉 | 74篇 |
儿科学 | 219篇 |
妇产科学 | 93篇 |
基础医学 | 3105篇 |
口腔科学 | 337篇 |
临床医学 | 1068篇 |
内科学 | 2104篇 |
皮肤病学 | 217篇 |
神经病学 | 1577篇 |
特种医学 | 235篇 |
外国民族医学 | 2篇 |
外科学 | 1012篇 |
综合类 | 1199篇 |
现状与发展 | 4篇 |
预防医学 | 600篇 |
眼科学 | 256篇 |
药学 | 1371篇 |
3篇 | |
中国医学 | 560篇 |
肿瘤学 | 413篇 |
出版年
2024年 | 18篇 |
2023年 | 224篇 |
2022年 | 281篇 |
2021年 | 581篇 |
2020年 | 424篇 |
2019年 | 446篇 |
2018年 | 454篇 |
2017年 | 435篇 |
2016年 | 436篇 |
2015年 | 416篇 |
2014年 | 739篇 |
2013年 | 874篇 |
2012年 | 650篇 |
2011年 | 733篇 |
2010年 | 591篇 |
2009年 | 610篇 |
2008年 | 603篇 |
2007年 | 513篇 |
2006年 | 474篇 |
2005年 | 468篇 |
2004年 | 385篇 |
2003年 | 332篇 |
2002年 | 255篇 |
2001年 | 253篇 |
2000年 | 230篇 |
1999年 | 229篇 |
1998年 | 239篇 |
1997年 | 270篇 |
1996年 | 233篇 |
1995年 | 210篇 |
1994年 | 208篇 |
1993年 | 183篇 |
1992年 | 152篇 |
1991年 | 148篇 |
1990年 | 124篇 |
1989年 | 125篇 |
1988年 | 98篇 |
1987年 | 85篇 |
1986年 | 71篇 |
1985年 | 143篇 |
1984年 | 117篇 |
1983年 | 93篇 |
1982年 | 74篇 |
1981年 | 66篇 |
1980年 | 53篇 |
1979年 | 35篇 |
1978年 | 21篇 |
1977年 | 20篇 |
1976年 | 12篇 |
1973年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Mitochondrial antigens as targets of cellular and humoral auto-immunity in primary biliary cirrhosis 总被引:3,自引:0,他引:3
Ichiki Y Selmi C Shimoda S Ishibashi H Gordon SC Gershwin ME 《Clinical reviews in allergy & immunology》2005,28(2):83-91
Several factors point toward an auto-immune pathogenesis for primary biliary cirrhosis (PBC), mostly based on the presence
of serum auto-antibodies to mitochondrial antigens (AMAs) and autoreactive T cells (both helper and cytotoxic). Interestingly,
epitopes recognized by AMA and T-cell clones are located within overlapping areas of the antigens. Moreover, a role for an
imbalance in cytokine pattern and for natural-killer lymphocytes has also been proposed. Despite several experimental reports,
no clear evidence is available regarding the interaction of these factors leading to bile duct destruction. This article reviews
the current reports regarding the auto-immune reaction against mitochondrial auto-antigens in PBC. 相似文献
102.
目的 观测家猪心脏三尖瓣复合体 ,为家猪心脏研究和心脏移植积累资料。方法 甲醛固定的家猪心脏 35例 ,大体解剖并观测三尖瓣复合体。结果 家猪心脏三尖瓣复合体由瓣环、瓣膜、腱索和乳头肌构成 ,瓣环周长为 70 75± 8 4 5mm ,前瓣、后瓣、隔侧瓣、前隔连合、前后连合、后隔连合的高度分别为 14 5 8±2 6 4、14 16± 2 5 0、12 84± 2 37、6 2 9± 1 97、6 86± 1 0 1、6 5 1± 1 36mm。前隔连合、前后连合、后隔连合的宽度分别为 6 4 0± 1 5 4、6 78± 1 2 3、6 4 3± 1 4 6 ;前乳头肌起始 ,腱索附着于前瓣、后瓣和前后连合的条数分别为 3 0 0± 0 97、3 0 9± 1 0 9、2 4 4± 1 16 ;后乳肌起始 ,腱索附着于后瓣、隔侧瓣和后隔连合的条数分别为 2 6 0± 0 6 9、3 0 9± 1 6 3、1 14± 0 4 3。隔侧乳头肌起始 ,附着于前瓣、隔侧瓣、前隔连合的腱索条数分别为1 71± 0 6 7、2 37± 1 2 6、0 94± 0 4 2。结论 家猪心脏三尖瓣复合体中各结构与人类相似 ,但大小有一定差异。 相似文献
103.
Monique Gromm Richard van der Valk Karen Sliedregt Leen Vernie Rob Liskamp Günter Hmmerling Jens-Oliver Koopmann Frank Momburg Jacques Neefjes 《European journal of immunology》1997,27(4):898-904
The major histocompatibility complex (MHC)-encoded transporter associated with antigen processing (TAP) translocates peptides from the cytosol into the lumen of the endoplasmic reticulum. This step precedes the binding of peptides to MHC class I molecules and is essential for cell surface expression of the MHC class I/peptide complex. TAP has a broad sequence specificity and a preference for peptides of around 9 amino acids. To synthesize inhibitors for TAP, we studied various alterations of the peptide substrate. The results indicate that TAP is stereospecific and that peptide bonds engineered into isosteric structures can improve translocation of the peptide. Furthermore, TAP is able to translocate peptides with large side chains that correspond to a peptide of ~ 21 amino acids in extended conformation. Peptides with longer side chains compete for the peptide binding site of TAP but fail to be translocated. Therefore, they represent the first rationally designed inhibitors of TAP. 相似文献
104.
目的通过对CT抗原(cancer-testis antigen)KM-HN-1进行HLA-A*0201限制性表位预测,并对候选表位肽与HLA-A*0201分子结合亲和力及复合物稳定性进行分析,为探索基于KM-HN-1的免疫治疗奠定基础。方法利用基于蛋白酶体剪切位点特异性的算法PAProc及基于肽MHC-I结合的算法BIMAS和SYFPEITHI对KM-HN-1进行HLA-A*0201限制性表位预测.合成KM-HN-1相关候选表位肽KM-HN-I321-329(KLLPFRETV),KM-HN-I303-211,(FLPTAPPNV),KM-HN-I629-637。(TLLQIIETV),KM-HN-I87-95(ILNKSIIEV),KM-HN-I538-596。(QMMEALDQL)及阳性对照肽HBVcAg18-27(FLPSDFFPSV);对这些合成肽与HIA-A*0201分子结合亲和力及其复合物稳定性根据文献报道的方法进行分析。结果KM-HN-I321-329(KLLPERETV)结合亲和力最低,KM-HN—I203-211(FLPTAPPNV)结合亲和力最高,其余3条肽结合亲和力介于2者之间;稳定性实验(DC50)结果显示:KM-HN-I538—546(QMMEALDQL)DC50小于2h,KM—HN-I321-329(KLLPERETV)的DC50介于2~4h之间,KM-HN-I87-95。(ILNKSIIEV)的DC50介于6~8h之间,KM-HN-I233-211(HLPTAPPNV)及KM-HN-I629—633(TLLQIIETV)的DC50均大于8h。结论基于蛋白酶体剪切位点特异性的算法及基于肽MHC-I结合的算法对KM-HN-1进行HLA-A*0201限制性表位预测,结合候选表位肽与HLA-A*0201分子结合的亲和力与复合物稳定性实验分析,为该抗原HLA-A*0201限制性表位的鉴定奠定了基础。 相似文献
105.
Antonella Coli Giulio Bigotti Soldano Ferrone 《Virchows Archiv : an international journal of pathology》1991,418(4):369-373
Summary This report describes the antigenic profile of the proliferating cells of pulmonary histiocytosis X (HX) in a patient treated with chemotherapy for Hodgkin's lymphoma; the association of pulmonary HX and Hodgkin's disease has rarely been described in the literature. The histopathological diagnosis of HX was confirmed with the aid of monoclonal antibodies (mAbs) to CD4, CD1a, and polyclonal serum anti S-100 protein. The phenotype of HX cells has been analysed using a panel of mAbs against HLA class I A, B, C monomorphic determinants, locus A and B,2-microglobulin, HLA class II distinct monomorphic determinants, DP, DQ, DR, intercellular adhesion molecule-1 (ICAM-1) and vitronectin receptors. Our results indicate that HX cells express HLA class I and II, including locus A, locus B and DP, DQ, DR, like their normal counterpart (represented by Langerhans cells) and detectable levels of ICAM-1 but not vitronectin receptors. We would like to stress the possibility of the association of HX and Hodgkin's lymphoma extending the immunophenotypic profile of HX cells. 相似文献
106.
107.
Miettinen R Riedel A Kalesnykas G Kettunen HP Puoliväli J Soininen H Arendt T 《Journal of chemical neuroanatomy》2005,30(2-3):105-118
Reelin, an extracellular matrix protein has an important role in the migration, correct positioning and maturation of neurons during development. Though it is generally down-regulated in the postnatal period, expression of this large glycoprotein continues in the adult brain in some cell populations. In the present study, we examined the distribution of reelin-immunoreactivity (-ir) in the hippocampal formation of 9-month-old wildtype mice (WT). Then, reelin-ir in normal mice was compared to that of transgenic mice (APP/PS1) carrying mutated human APP and PS1 genes, which are linked to the familial form of Alzheimer's disease (AD). The APP/PS1 mice were additionally burdened with a second risk factor for AD, namely depletion of circulating gonadal hormones by ovariectomy (APP/PS1 + OVX). The analyses revealed that in adult WT reelin-ir is expressed by Cajal-Retzius cells and a subgroup of interneurons throughout the hippocampal formation. In addition, layer II projection neurons in the lateral entorhinal subfields are reelin-ir. Interestingly, ovariectomy decreases the number of reelin-ir cells in the hilus in WT mice, whereas AD-related genotype alone induces only a non-significant reduction. Unexpectedly, additional stress, e.g., depletion of gonadal hormones, does not aggravate the slight reduction in the reelin cell number in the APP/PS1 mice. We propose that the changes in normal reelin-ir are linked to disturbances in repair mechanisms in which APP/PS1 and gonadal hormones are involved and which are perturbed in neurodegenerative conditions, namely AD. 相似文献
108.
L. Deecke D. W. F. Schwarz J. M. Fredrickson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,30(2-3):219-232
Summary The vestibular thalamic relay in the Rhesus ventrobasal complex, identified in a previous field potential study (part I, Deecke et al., 1974), has now been investigated with neuronal recordings in the thalamus in order to clarify its functional role. In part I, short latency responses (2.5 msec) were found in the corner between VPL, VPM and VPI nuclei, largely including dorsal portions of the VPI nucleus. Field potentials of somewhat longer latency (4–5 msec) were recorded in VPL and in other thalamic nuclei, including the posterior nuclear group.Neuronal responses were recorded in thalamic nuclei of awake flaxedilized Rhesus monkeys. Cells not responding to vestibular stimulation (round window polarisation of either labyrinth) were ignored. The great majority (80%) of those neurons responding to labyrinth polarisation showed convergence with deep somatic (proprioceptive) input from joints and muscles of vertebral column and limbs. 60% of these bimodal neurons responded to movement of cervical joints. Very few vestibularly responsive cells received cutaneous (6.6%), non-optokinetic visual or auditory (2.6% each) input. Proprioceptive fields tended to be large, frequently involving more than one joint, and could be even bilateral. For a few cells the pattern of vestibulo-proprioceptive convergence could be fitted to a coordinated body position that might occur during normal locomotion. 78% of the cells responded to polarisation of both labyrinths, indicating strong bilateral projection. 相似文献
109.
Mononuclear cells in glomeruli and cytokines in urine reflect the severity of experimental proliferative immune complex glomerulonephritis. 总被引:3,自引:3,他引:3 下载免费PDF全文
B Noble K Ren J Taverne J Dipirro J Van Liew C Dijkstra G Janossy L W Poulter 《Clinical and experimental immunology》1990,80(2):281-287
Immunohistochemical methods were used to investigate the role of macrophages in the progression of proliferative immune complex glomerulonephritis. The mononuclear cell component of glomerular inflammation was analysed in three different stages of chronic serum sickness, each of which was clearly distinguished by criteria of kidney function. Urinary excretion of the macrophage secretory products interleukin-1 and tumour necrosis factor was also evaluated in relation to the functional severity of kidney disease. T lymphocytes and macrophages began to accumulate in glomeruli at the onset of proteinuria, but not before. Urinary excretion of interleukin-1 also began with proteinuria. Proteinuria increased in direct correlation with increases in the number of glomerular macrophages. Development of the most severe stage of glomerulonephritis, characterized by cachexia, declining kidney function, and necrotizing glomerular pathology, was accompanied by the disappearance of T cells from glomeruli and the expression of highly abnormal phenotypes by most macrophages. In addition, there was a switch from urinary excretion of interleukin-1 to excretion of tumour necrosis factor. The progression of proliferative immune complex glomerulonephritis was associated with qualitative as well as quantitative changes in glomerular macrophage populations. Differentiation and/or activation of those glomerular macrophages may have resulted from local T cell-mediated immunoregulation. Measurements of urinary cytokine excretion provided a reliable means of monitoring disease progression. The local action of tumour necrosis factor probably contributed to declining kidney function in the most severe stage of disease. 相似文献
110.