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目的 :了解新生儿缺氧缺血性脑病 (HIE)时血浆和脑脊液 (CSF)中 NO水平的动态变化。方法 :采用硝酸根还原酶法 ,对 35例 HIE患儿 (轻度 10例、中度 13例、重度 12例 )分别于急性期、恢复期进行了血浆和 CSF NO水平测定。结果 :HIE急性期血浆 NO水平除轻度组外 ,中、重度组明显高于对照组 ,重度组又明显高于轻、中度组 ;恢复期轻、中、重度组血浆 NO水平均降至正常 ,与对照组比较差异无显著性。CSF中 NO水平增加的幅度与血浆成正比。结论 :血浆和 CSF中 NO水平与 HIE的脑损伤程度密切相关 相似文献
84.
- Modulation of presynaptic voltage-dependent calcium channels (VDCCs) by muscarinic receptors at the CA3–CA1 synapse of rat hippocampal slices was investigated by using the calcium indicator fura-2. Stimulation-evoked presynaptic calcium transients ([Capre]t) and field excitatory postsynaptic potentials (fe.p.s.ps) were simultaneously recorded. The relationship between presynaptic calcium influx and synaptic transmission was studied.
- Activation of muscarinic receptors inhibited [Capre]t, thereby reducing synaptic transmission. Carbachol (CCh, 10 μM) inhibited [Capre]t by 35% and reduced fe.p.s.p. by 85%. The inhibition was completely antagonized by 1 μM atropine. An approximate 4th power relationship was found between presynaptic calcium influx and postsynaptic responses.
- Application of the N-type VDCC-blocking peptide toxin ω-conotoxin GVIA (ω-CTx GVIA, 1 μM) inhibited [Capre]t and fe.p.s.ps by 21% and 49%, respectively, while the P/Q-type VDCC blocker ω-agatoxin IVA (ω-Aga IVA, 1 μM) reduced [Capre]t and fe.p.s.ps by 35% and 85%, respectively.
- Muscarinic receptor activation differentially inhibited distinct presynaptic VDCCs. ω-CTx GVIA-sensitive calcium channels were inhibited by muscarinic receptors, while ω-Aga IVA-sensitive channels were not. The percentage inhibition of ω-CTx GVIA-sensitive [Capre]t was about 63%.
- Muscarinic receptors inhibited presynaptic VDCCs in a way similar to adenosine (Ad) receptors. The percentage inhibition of ω-CTx GVIA-sensitive [Capre]t by Ad (100 μM) was about 59%. There was no significant inhibition of ω-Aga IVA-sensitive channels by Ad. The inhibitions of [Capre]t by CCh and Ad were mutually occlusive.
- These results indicate that inhibition of synaptic transmission by muscarinic receptors is mainly the consequence of a reduction of the [Capre]t due to inhibition of presynaptic VDCCs.
85.
采用原子吸收分光光度法,测定了78 例肾小球疾病患儿血清铜、锌、铁、镁4 种元素。结果显示,单纯性肾病组、肾炎性肾病组、紫癜性肾病组及肾炎组血清锌均显著低于正常组( P< 005),血清铁、镁与正常组比较无显著差异。单纯性肾病组,肾炎性肾病组血清铜显著低于正常组( P< 005)。提示血清铜、锌、铁、镁含量的变化与疾病发生和疾病状态有关。 相似文献
86.
以对氨基苯磺酸修饰聚乙二醇端头,制备兼具刚性与极性端头的聚合物,考察其制备LB膜与自组装膜的条件,用原子力/摩擦力显微镜表征自组装膜的表面形貌,对其微摩擦性能进行初步的探讨。 相似文献
87.
目的:根据各种蛋白质在一定的泳动条件下,都有一定的相对迁移率不同的特点,分析615 纯系小鼠血清中的蛋白质在聚丙烯酰胺凝胶上的分布,进行了定位分析。方法:采用高pH 不连续性聚丙烯酰胺凝胶电泳及蛋白质特殊染色法。结果:615 鼠血清蛋白质在聚丙烯酰胺凝胶上可分离出13 ~15 条区带,脂蛋白3 条、白蛋白2 条、糖蛋白5 条、铜蓝蛋白1 条、血红蛋白1 条、结合珠蛋白3 条。根据每种蛋白质的Rm 值定位顺序从阳极到阴极依次为1 .糖蛋白、2.脂蛋白、3 .白蛋白、4.脂蛋白、5 .糖蛋白、6 .巨球蛋白( 根据其它资料) 、7 .铜蓝蛋白、8 .结合珠蛋白、9 .Hb、10 .运铁蛋白( 根据其它资料)、11 .脂蛋白、12 ~14 .均为糖蛋白。光密度扫描615 鼠血清蛋白质相对面积比分别为白蛋白为48-4、α1 球蛋白为6-9、α2 球蛋白23-8 、β球蛋白为5-0 、γ球蛋白为13-8 。结论:615 鼠血清蛋白质的定位分析对于615 鼠可移植性淋巴细胞型白血病鼠的蛋白质研究具有一定的实际意义,利用Rm 值来作蛋白质定位分析简单易行,关键在于掌握实验条件的恒定。 相似文献
88.
α1-抗糜蛋白酶基因、早老素1基因
与阿尔茨海默病的相关分析 总被引:1,自引:0,他引:1
目的探讨中国汉族人中α1抗糜蛋白酶(AACT)基因、早老素1(PS1)基因多态性与阿尔茨海默病(Alzheimersdisease,AD)的相关情况。方法应用PCRRFLP方法,在123例患者和140例正常人中观察AACT信号肽和PS1基因多态性的分布,进行关联分析。结果1AD患者与PS1基因等位基因1正关联,与等位基因2和基因型2/2负关联,但与1/1基因型无关;2AACT信号肽基因多态性与AD无关联;3在三种PS1基因型中,AACT信号肽基因多态性与AD均无关;4在AACT基因AA、TT基因型中,PS1基因多态性与AD负关联,而TA型中PS1基因与AD无显著相关。结论中国人群中,AD与PS1基因2/2型负关联,而与AACT信号肽基因多态性无关;AACT信号肽和PS1基因多态性之间也无明显的相互影响。 相似文献
89.
Lorber MI Wilson JH Robert ME Schechner JS Kirkiles N Qian HY Askenase PW Tellides G Pober JS 《Transplantation》1999,67(6):897-903
BACKGROUND: Interspecies differences create important shortcomings in existing animal models used to describe in vivo events responsible for allograft rejection. Alloimmune destruction of human dermal microvessels, histologically consistent with rejection, has been demonstrated in human skin-grafted severe combined immunodeficient (SCID) mice receiving allogeneic human peripheral blood mononuclear cells (PBMC). We have now documented human alloimmune injury in a vascularized, SCID-human arterial transplantation model. METHODS: Fresh human artery was used to replace the CB.17 SCID/beige mouse infrarenal aorta. Seven days later, 3x10(8) human PBMC were administered intraperitoneally, and lymphocyte engraftment was considered successful when circulating human CD3+ cells were later identified in peripheral blood. RESULTS: Forty-six of 49 (94%) mice undergoing transplantation survived, including 14 controls with arterial grafts receiving no PBMC. Twenty-eight of 32 mice demonstrated circulating human CD3+ cells, 14 days after PBMC administration. Animals were killed at 14, 21, or 28 days after receiving allogeneic PBMC, and arteries were recovered for histology and immunohistology. All 14 control mice had patent transplanted grafts with normal vascular histology and no lymphoid infiltration. Damage to transplanted arteries among lymphocyte-engrafted mice was apparent by 14 and 21 days in some animals, whereas 16 of 22 exhibited moderate to severe intimal, medial, and/or adventitial lymphocytic infiltration with intimal expansion by day 28. The infiltrate consisted of HLA-A, -B, -C+, and -DR+, human CD3+ cells, approximately equally distributed as CD4+ and CD8+ subsets. Some infiltrating lymphocytes were cytolytic cells as demonstrated by perforin staining. The endothelium of transplanted human arteries exhibited endothelialitis, and the endothelial cells stained intensely with anti-HLA-A, -B, -C and anti-HLA-DR antibodies. The expanded intima was predominantly smooth muscle cells, staining positively for smooth muscle alpha-actin, HLA-A, -B, -C and HLA-DR. Medial necrosis was not observed. CONCLUSION: The results provide evidence of alloimmune-mediated vascular rejection in this human arterial transplantation model. 相似文献
90.