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21.
从人肝癌组织中提取总RNA,RT—PCR合成hTIMP-1的全长cDNA,克隆到腺病毒载体AdEasy系统的穿梭质粒pAdTraek—CMV上,与骨架质粒pAdEasy-1在BJ5183受体菌中进行同源重组,成功构建含hTIMP-1全长eDNA的重组腺病毒载体,经293细胞的包装、扩增,生成含hTIMP-1基因的重组腺病毒AdhTIMP-1并实现体外表达,为进一步研究肝癌浸润和转移机理以及肝癌的基因治疗提供实验基础。  相似文献   
22.
Stroke is a common cause of death and disability in our society. Stroke is associated with changes in immune responses within the central nervous system as well as systemically. The cells contributing to such changes as well as the factors contributing to formation of the inflammatory infiltrate observed in stroke remain to be clarified. In this study, blood monocytes and corresponding mononuclear cells (MNC) were separated and examined in parallel within 4 days and 1–3 months after onset of ischemic stroke. Numbers of TNF--, IL-12-, IL-6-, and IL-10-secreting cells and of cells expressing mRNA for matrix metalloproteinase (MMP)-1, -2, -7, -9 and tissue inhibitor of MMP (TIMP)-1 were studied. The TNF--, IL-12-, and IL-6-secreting monocytes and MNC were elevated during the acute phase compared to healthy controls. Such differences were not observed when stroke patients were examined during convalescence. The IL-10-secreting monocytes did not change over the course of stroke. Levels of monocytes expressing MMP-1, MMP-7 and TIMP-1 mRNA were elevated in the acute phase of stroke patients compared to convalescence and healthy controls, as were levels of MMP-1, -2, -7, -9 and TIMP-1 mRNA expressing blood MNC. The MMP-2 and -9 activity as measured by zymography also was higher in MNC supernatants in the acute phase of stroke compared to convalescence. The high levels of proinflammatory cytokines and MMPs in blood monocytes and MNC further demonstrate the presence of systemic aberrations in the acute phase of stroke. Such changes may contribute to the influx of blood-borne cells into the ischemic lesions during the acute phase of stroke.  相似文献   
23.
Two unrelated adult sibling cases (36- and 32-year-old females) of Juvenile hyaline fibromatosis are presented. The parents of one of these patients were non-consanguineous but natives of a small Island, and one elder sister among four siblings was affected with the same disease. The parents of the other patient were consanguineous, and one other sibling suffered from the identical disease. Both patients presented with multiple subcutaneous nodules, which they had had since infancy, and had undergone numerous surgical excisions. Light microscopy examination of skin lesions from both patients showed identical histology; an abundance of a homogenous, amorphous, eosinophlllc extracellular matrix in which spindle-shaped cells were embedded. Electron microscopically, the spindle-shaped cells had hypertrophic Golgi apparatus and dilated, rough endoplasmlc reticulum. Fine flbrillar and granular material-filled structures, the contents of which were occasionally released into the extracellular matrix, were also seen, immunohistochemically, the spindle-shaped cells were vlmentin-positive but negative for α-smooth muscle actln and S-100 protein, and the hyaline ground substance was positive for type I and type III collagen but negative for type II and type IV collagen and tenascin. Matrix metalloprotelnase-1, -2, and -9, and tissue inhibitor of matrix metalloproteinase (TlMP)-2 was positive but TIMP-1 was negative. A review of 39 cases of juvenile hyaline fibromatosis In the literature is also presented. In summary, skin lesions may be the most outstanding symptoms of juvenile hyaline fibromatosis, but joint contracture and gingival hypertrophy precede the skin manifestation.  相似文献   
24.
目的筛选与涎腺腺样囊性癌转移相关的候选基因,并对其中的候选基因进行初步的验证。方法用限制片段差异显示PCR技术(restriction fragments differential display PCR, RFDD-PCR)建立涎腺腺样囊性癌高、低转移细胞株(ACC-M、ACC-2)的表达谱。对两个表达谱的片段进行比较,通过生物信息学的分析,初步筛选出候选基因。用半定量逆转录PCR技术对筛选出的基因进行初步验证。结果RFDD-PCR方法共获得5420个基因片段,其中包含12个基质金属蛋白酶(matrix metalloproteinase,MMP)基因。半定量逆转录PCR方法发现MMP2、MMP7、MMP9、MMP14、MMP15、MMP24在ACC-M和ACC-2中的表达存在明显差异。结论构建了ACC-M和ACC-2细胞株的表达谱,为寻找目的基因奠定了基础。发现MMP2、MMP7、MMP9和MMP15与涎腺腺样囊性癌的发生、发展、转移有关,不同肿瘤细胞的转移能力可能与不同的MMPs家族基因相关。  相似文献   
25.
Several growth factor ligand and receptor gene products havebeen shown to play roles during preimplantation mammalian development.Genes for insulin-like growth factors (IGFs), transforming growthfactors (TGFs), fibroblast growth factor (FGF), platelet-derivedgrowth factor (PDGF) and receptors for insulin, IGF, PDGF, TGFand epidermal growth factor (EGF) are expressed by early embryosof several species including mouse, rat, cow and sheep. Rolesof growth factors during early development have been demonstratedby addition of purified growth factors to culture medium orby molecular genetic techniques that interfere with gene expression.In this way, it has been shown that successful development ofthe blastocyst is dependent on the action of epidermal growthfactor (EGF) and leukaemia inhibitory factor (LIF). Recent experimentsshow that both LIF and EGF stimulate secretion of urokinase-typeplasminogen activator (uPA) and gelatinase B/ matrix metalloproteinase-9(MMP-9) in day 7 mouse blastocyst outgrowths. At the same time,tissue inhibitors of MMPs (TIMPs) are also expressed by embryonic,decidual and uterine tissues during the implantation process.It appears that LIF may act directly or indirectly, by inducingthe expression of other cytokines, to regulate the temporaland spatial production and activity of proteases and proteaseinhibitors to create a favourable environment for implantation.  相似文献   
26.
Leflunomide, an isoxazol derivative structurally unrelated to other immunomodulatory drugs, has proven to be efficacious in the treatment of rheumatoid arthritis (RA). This study was conducted to elucidate the mechanism by which leflunomide mediated antirheumatic effects. We investigated the effects of A77 1726, leflunomide's active metabolite, on mitogen-activated protein kinase (MAPK) activation in IL-1beta-stimulated rheumatoid synovial fibroblasts. The effects of A77 1726 on the secretion of matrix metalloproteinases (MMPs) from rheumatoid synovial fibroblasts were also examined. A77 1726 partially suppressed IL-1beta-induced ERK1/2 and p38 kinase activation. In contrast, A77 1726 efficiently suppressed IL-1beta-stimulated JNK1/2 kinase activation. Although no suppressive effect was demonstrated on MMP-2, A77 1726 markedly inhibited MMP-1, 3, and 13 secretions from IL-1beta-stimulated rheumatoid synovial fibroblasts. Tissue inhibitor of metalloproteinases-1 (TIMP-1) was constitutively produced from rheumatoid synovial fibroblasts and the suppressive effects of A77 1726 on TIMP-1 production were minimal. Our results suggest that the suppression of the MAPK signalling pathway and MMP synthesis in rheumatoid synovial fibroblasts is a possible mechanism for the inhibitory activity of leflunomide against rheumatoid arthritis.  相似文献   
27.
The studies described here examine the involvement of the fibrinolytic cascade and its endogenous inhibitors in the regulation of activity of matrix metalloproteinases and cartilage degradation related to non-inflammatory joint disease, like osteoarthritis. An interleukin-1-induced model of degradation using [35S]-labeled bovine and human articular cartilage explants was utilized. One goal of these studies was to compare the responses of bovine and human articular cartilage. Degradation was not inhibited by 1-PI, PAI-1, 2-macroglobulin, 2-antiplasmin or TIMP-2, when IL-1 alone was added. Addition of human plasminogen to bovine explants, at concentrations found in human synovial fluid, increased degradation by three to fourfold. Under these conditions, the degradation was inhibited effectively by all of the endogenous inhibitors tested, indicating the presence of a cascade where activated chondrocytes are a source of u-PA. Plasminogen activated by u-PA gives plasmin, which is known to further activate pro-stromelysin. Stromelysin is essential for activation of collegenase. Not only TIMP, but also inhibitors at earlier steps of activation like PAI-1, 2-antiplasmin, 1-PI and 2-macroglobulin inhibited degradation, and could provide cartilage protection in vivo. An experiment with human articular cartilage explants showed that very little or no degradation occurred when human articular cartilage explants were stimulated with interleukin-1 alone. Addition of human plasminogen (at physiologically relevant concentrations) resulted in significant degradation, which was inhibited in the same manner as in bovine explants, by inhibitors of the fibrinolytic cascade and TIMP. TIMP is much more efficient in human explants, indicating the limited participation of human plasmin in the degradation of human cartilage. Although speculative, it is possible that in vivo, cartilage degradation could be promoted not only by TIMP/MMP imbalance, but also accelerated by decreased levels of certain serpins in synovial fluid (e.g. PAIs, 2-antiplasmin and 1-PI).accepted by W. B. van den BergWork supported by OsteoArthritis Science Inc., One Kendall Square, Bldg. 200, Cambridge, MA 01139, USA.  相似文献   
28.
张萍  钟梅 《南方医科大学学报》2001,21(12):929-931,934
目的研究基质金属蛋白酶2(MMP-2)、基质金属蛋白酶抑制剂1(TIMP-1)在离体成骨细胞上的表达特点及雌、孕激素对MMP-2、TIMP-1的影响,初步探讨MMP-2、TIMP-1在骨吸收中的作用。方法采用免疫组化方法对成骨细胞中MMP-2蛋白的表达进行检测。采用逆转录定量PCR检测雌、孕激素对成骨细胞分泌MMP-2、TIMP-1mRNA的影响。结果MMP-2蛋白在成骨细胞上表达阳性,雌激素对MMP-2蛋白的表达有抑制作用,成骨细胞分泌的MMP-2在雌、孕激素作用下呈剂量依赖性下降。成骨细胞分泌的TIMP-1在雌、孕激素作用下变化不显著。结论雌、孕激素可通过对成骨细胞MMP-2的抑制作用促进骨形成、减缓骨吸收和骨基质降解。孕激素治疗绝经后骨质疏松症与雌激素同样具有重要意义。  相似文献   
29.
BackgroundIncisional hernias (IH) following a laparotomy, on average, occur in 10–20% of patients, however, little is known about its molecular basis. Thus, a better understanding of the molecular mechanisms could lead to the identification of key target(s) to intervene pre-and post-operatively.MethodsWe examined the current literature describing the molecular mechanisms of IH and overlap these factors with smoking, abdominal aortic aneurysm, obesity, diabetes mellitus, and diverticulitis.ResultsThe expression levels of collagen I and III, matrix metalloproteinases, and tissue inhibitors of metalloproteases are abnormal in the extracellular matrix (ECM) of IH patients and ECM disorganization has an overlap with these comorbid conditions.ConclusionUnderstanding the pathophysiology of IH development and associated risk factors will allow physicians to identify patients that may be at increased risk for IH and to possibly act preemptively to decrease the incidence of IH.  相似文献   
30.
目的:分析抗结核药物导致的肝损伤(anti-tuberculosis drug-induced liver injury,ATB-DILI)患者基质金属蛋白酶类(matrix metalloproteinases,MMP)水平及其相关性。方法:采用回顾性研究方法,收集2019年6月至2020年6月昆明市第三人民医院收治的肺结核患者中发生ATB-DILI的98例患者作为病例组;选取同期门诊健康体检者30名作为对照组。采集研究对象晨起空腹静脉血6 ml,采用双抗体夹心法检测其MMP-1、MMP-2、MMP-7、MMP-9、MMP-13、MMP-14浓度。病例组研究对象根据ATB-DILI临床分型分为肝细胞损伤型(A组)、胆汁淤积型(B组)、肝血管损伤型(C组)、混合型(D组);根据ATB-DILI严重程度分为0级(无肝损伤)、1级(轻度肝损伤)、2级(中度肝损伤)、3级(重度肝损伤)、4级(急性肝功能衰竭)、5级(致命)。比较不同临床分型组及对照组研究对象MMP水平;分析MMP水平与ATB-DILI严重程度分级相关性。结果:按照ATB-DILI临床分型,病例组中A组有51例,B组有12例,C组有15例,D组有20例;根据ATB-DILI严重程度分级,病例组中1级有33例,2级有27例,3级有22例,4级有14例,5级有2例。A、B、C、D组及对照组MMP-1浓度分别为:(89.1±11.2)ng/ml、(32.3±6.3)ng/ml、(47.5±9.1)ng/ml、(55.2±11.1)ng/ml、(27.5±8.2)ng/ml;MMP-2浓度分别为:(8.2±2.1)ng/ml、(6.2±2.3)ng/ml、(15.5±1.8)ng/ml、(7.2±1.6)ng/ml、(3.2±1.3)ng/ml;MMP-9浓度分别为:36.1(25.9,47.3)ng/ml、11.3(5.1,20.6)ng/ml、14.1(6.1,21.3)ng/ml、15.3(3.8,28.1)ng/ml、6.4(2.8,8.6)ng/ml;MMP-14浓度分别为:5.2(2.8,7.5)ng/ml、6.0(3.6,8.9)ng/ml、11.2(5.2,17.4)ng/ml、4.0(1.8,6.2)ng/ml、2.8(1.4,4.3)ng/ml。A组MMP-1和MMP-9浓度明显升高,C组MMP-2和MMP-14浓度明显升高,差异均有统计学意义(F=7.983,P=0.031;H=9.979,P=0.041;F=9.381,P=0.010;H=10.555,P=0.032)。ATB-DILI严重程度1、2、3、4、5级患者MMP-9浓度分别为:16.2(13.2,19.3)ng/ml、21.5(18.4,23.6)ng/ml、24.3(20.6,27.1)ng/ml、30.3(25.1,35.3)ng/ml、38.5(33.9,43.1)ng/ml,与严重程度分级呈正相关(r=0.882,P=0.000)。结论:不同临床分型ATB-DILI患者MMP-1、MMP-2、MMP-9、MMP-14浓度有不同程度升高;MMP-9浓度与ATB-DILI严重程度呈正相关;MMP水平可能为ATB-DILI发生的影响因素。  相似文献   
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