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91.
本研究旨在探讨细胞间黏附分子1(ICAM-1,CD54)在初诊儿童肿瘤及急性白血病细胞上的阳性表达率,以了解其分布规律及其临床意义。采用免疫组织化学方法检测46例儿童实体瘤的病理组织切片ICAM-1的阳性率,通过流式细胞仪检测60例儿童急性白血病细胞上ICAM-1的阳性率。儿童实体瘤包括淋巴瘤10例,肝母细胞瘤3例,神经母细胞瘤6例,横纹肌肉瘤2例,尤文氏肉瘤6例,纤维肉瘤2例,原始神经外胚层肿瘤5例,肾母细胞瘤11例,骨肉瘤1例;急性白血病包括急性淋巴细胞白血病(ALL)20例,急性非淋巴细胞白血病(ANLL)40例(M1 6例、M2 7例、M3 7例、M4 15例、M5 5例)。结果表明,儿童肿瘤组中3例肝母细胞瘤ICAM-1全部阳性,而在淋巴瘤、横纹肌肉瘤、神经母细胞瘤及尤文氏肉瘤阳性率不高,纤维肉瘤、肾母细胞瘤及原始神经外胚层肿瘤患儿中未见ICAM-1表达。急性白血病组中ALL的ICAM-1阳性率为55%,ANLL的M1、M2、M3型ICAM-1的阳性率为65%,M4、M5型为50%。结论:ICAM-1在儿童肿瘤、急性白血病细胞上的表达呈一定变异性,其在肝母细胞瘤及ANLL(M1、M2和M3)上阳性率高,而在纤维肉瘤、肾母细胞瘤及原始神经外胚层肿瘤等中不表达。  相似文献   
92.
老年冠心病患者血清脂质与脂质过氧化的关系   总被引:2,自引:0,他引:2  
本文观察了44例老年冠心病者及30例健康老年人血脂水平及丙二醛和超氧化物歧化酶的血清含量。  相似文献   
93.
OBJECTIVES: An in situ model was used to test whether and how multiple occlusions at reperfusion can protect rabbit myocardium. BACKGROUND: Recently it was demonstrated that postconditioning in dogs salvaged ischemic myocardium. METHODS: Control hearts underwent 30-min regional ischemia/3-h reperfusion, whereas in experimental hearts four postconditioning cycles of 30-s occlusion/30-s reperfusion starting 30 s after release of the index coronary occlusion were added in the presence or absence of various cell signaling antagonists. RESULTS: Postconditioning decreased infarction from 35.4 +/- 2.7% of the risk zone in control hearts to 19.8 +/- 1.8% (p < 0.05). Six cycles did not result in greater protection. If postconditioning cycles were begun after 10 min of reperfusion, protection was no longer evident. Either the non-selective K(ATP) channel closer glibenclamide or the putatively selective mitochondrial K(ATP) channel antagonist 5-hydroxydecanoate administered 5 min before reperfusion blocked the protection afforded by postconditioning, indicating involvement of the mitochondrial K(ATP) channel. PD98059, a mitogen-activated protein/extracellular-signal regulated kinase (MEK) 1/2 and therefore extracellular-signal regulated kinase (ERK) inhibitor, and N(omega)-nitro-L-arginine methyl ester, an antagonist of nitric oxide synthase, infused shortly before reperfusion also aborted the protection afforded by postconditioning. Combined ischemic postconditioning and preconditioning resulted in significantly greater protection than either alone. CONCLUSIONS: Multiple, short, regional coronary occlusions immediately after prolonged myocardial ischemia are an effective cardioprotective intervention in the rabbit, and the mechanism of protection involves activation of ERK, production of nitric oxide, and opening of mitochondrial K(ATP) channels. These observations suggest that a similar approach could be applied in the cardiac catheterization laboratory to protect reperfused myocardium after primary angioplasty in patients with acute myocardial infarction.  相似文献   
94.
The composition of atherosclerotic plaques, not just macroscopical lesion size, has been implicated in their susceptibility to rupture and the risk of thrombus formation. By focusing on the quality of lipids, macrophages, apoptosis, collagen, metalloproteinase expression and plaque integrity, we evaluated the possible anti-atherosclerotic effect of the antioxidants alpha-tocopherol and astaxanthin in Watanabe heritable hyperlipidemic (WHHL) rabbits. Thirty-one WHHL rabbits were divided into three groups and were fed a standard diet, as controls (N =10), or a standard diet with the addition of 500 mg alpha-tocopherol per kg feed (N =11) or 100 mg astaxanthin per kg feed (N =10) for 24 weeks. We found that both antioxidants, particularly astaxanthin, significantly decreased macrophage infiltration in the plaques although they did not affect lipid accumulation. All lesions in the astaxanthin-treated rabbits were classified as early plaques according to the distribution of collagen and smooth muscle cells. Both antioxidants also improved plaque stability and significantly diminished apoptosis, which mainly occurred in macrophages, matrix metalloproteinase three expressions and plaque ruptures. Although neither antioxidant altered the positive correlations between the lesion size and lipid accumulation, the lesion size and apoptosis were only positively correlated in the control group. Astaxanthin and alpha-tocopherol may improve plaque stability by decreasing macrophage infiltration and apoptosis in this atherosclerotic setting. Apoptosis reduction by alpha-tocopherol and astaxanthin may be a new anti-atherogenic property of these antioxidants.  相似文献   
95.
As a non-invasive method, low-intensity pulsed ultrasound (LIPUS) can accelerate fracture healing. The mechanisms responsible for the enhanced fracture healing need to be studied further. Activation of YAP/TAZ, key mediators of the Hippo signaling pathway, could promote angiogenesis and vascular remodeling. The purpose of this study was to determine whether LIPUS treatment can activate YAP/TAZ. Human umbilical vein endothelial cells (HUVEC) were used. After LIPUS treatment, Western blot and immunofluorescence staining were used for YAP/TAZ activation. Small interfering RNA (siRNA) of YAP and short hairpin LATS1/2 (shLATS1/2) were used to check whether there is cross-talk with the Hippo pathway. The phosphorylated YAP (p-127 and p-397) protein increased more than 3-fold 0.5 h after LIPUS treatment (p < 0.05). TAZ protein increased 3.0-, 2.0- and 1.5-fold 0.5, 6 and 12 h after LIPUS treatment. We found that LIPUS treatment activates YAP/TAZ, which is translocated into the cell nucleus to activate target genes. This process can be inactivated by siYAP and activated by shLATS1/2. The cross-talk with the Hippo pathway can initiate angiogenesis so as to accelerate fracture healing by LIPUS.  相似文献   
96.
97.
A novel poly(arylene ether) with azo-coupled cobalt phthalocyanine in the side chain (PAE-azo-CoPc) was prepared by 1,2-benzodinitrile, anhydrous cobaltous chloride and a novel azobenzene-containing poly(aryl ether) (PAE-azo-DCN) via a nucleophilic substitution polycondensation based on a novel bisfluoro monomer, 4-[(3,4-cyanophenyl)diazenyl]phenyl-2,6-difluorobenzoate. The obtained polymers were characterized and evaluated by FT-IR, 1H NMR, DSC and TGA. PAE-azo-CoPc exhibited higher glass transition temperature and better thermal stability than PAE-azo-DCN because of the introduction of cobalt phthalocyanine groups. The results of Z-scan measurements demonstrated that PAE-azo-CoPc showed reversible saturable absorption and positive refraction, and PAE-azo-DCN showed saturable absorption and negative refraction. By calculation, PAE-azo-CoPc exhibited larger third-order nonlinear optical susceptibilities than that of PAE-azo-DCN. The results of optical limiting measurements demonstrated that the PAE-azo-CoPc exhibited an excellent optical limiting response.

A novel poly(arylene ether) with azo-coupled cobalt phthalocyanine in the side chain was prepared by 1,2-benzodinitrile, anhydrous cobaltous chloride and a novel azobenzene-containing poly(aryl ether).  相似文献   
98.
事务处理是现代应用系统的基础支撑部件,也是Web服务能否成功支持商务应用的关键技术.但由于环境的高度分布与自治性,传统的可串行化理论已不能再作为Web事务的正确性标准.本文放松了事务的原子性规定,将事务看作由若干原子单元组成的偏序集,并将可串行性扩展为事务的弱可串行性,作为事务的正确性标准.文章最后给出了一个完全分布式的事务并发控制算法,用以实现弱串行性的判定.  相似文献   
99.
利用自制的人胎脑提取液观察其对小鼠宫颈癌肺转移倾向亚株(U_(14)AP_(11))、淋巴结转移倾向亚株(U_(14)AL_(10))动物模型的影响.发现该提取液能够改善荷瘤动物的一般状态;提高腹腔巨噬细胞的功能活动;提高血中辅助性T细胞,单核细胞的比例;并调整二者间比例;减少死亡数;将肺转移率由100%降至44%,淋巴结转移率由93%降至46.67%.提示该提取液有极佳的临床应用前景.  相似文献   
100.
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