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91.
92.
研究了欧芹素乙(Imperatorin,Imp)和异欧芹素乙(Iso-imperatorin,Isi)及对照药物维拉帕米(Verapamil,Ver)对小鼠腹腔巨噬细胞体外释放肿瘤坏死因子(Tumornecrosisfactor,TNF)的影响。结果表明:Imp、Isi及Ver对小鼠腹腔巨噬细胞体外释放TNF具有显著的抑制作用。药物浓度在10-6~10-4mol/L范围内,该抑制作用呈剂量依赖性:药物浓度达10-4mol/L时,则可完全抑制TNF的释放。 相似文献
93.
94.
活血化瘀中药联合血管内皮生长因子基因转移促进股骨头坏死处新生血管形成的实验研究 总被引:5,自引:4,他引:1
目的:观察活血化瘀中药联合血管内皮生长因子(VEGF)基因转移对促进股骨头缺血坏死处新生血管形成情况。方法:日本大耳兔40只,随机分为对照组、模型组、中药组、基因组和综合组。治疗8周后采用免疫组织化学方法观察股骨头滑膜VEGF阳性细胞率及数字减影血管造影股骨头血管数目改变情况。结果:模型组VEGF阳性细胞表达率减低,与对照组、基因组、综合组比较,差异有显著性意义(P<0.01),与中药组比较,有统计学差异(P<0.05),综合组VEGF阳性细胞表达率较高,与中药组及基因组比较,有统计学差异(P<0.05)。血管数目:在A区,各组与模型组比较,均无统计学差异;在B区,各组较模型组血管数目均有增加,对照组、基因组、综合组与模型组比较,有统计学差异(P<0.05)。综合组与基因组比较有统计学差异(P<0.05),中药组虽然血管数目较模型组多,但是无统计学意义。结论:活血化瘀中药及VEGF基因转移均可促进股骨头缺血坏死处局部新生血管形成和侧支循环的建立,尤以活血化瘀中药联合基因疗法效果为好,为临床应用活血化瘀中药联合基因疗法治疗股骨头缺血性坏死提供实验依据。 相似文献
95.
2型糖尿病肾病患者血清中TNF-α、NO与ET的水平变化及其临床意义 总被引:1,自引:0,他引:1
目的:探讨2型糖尿病肾病患者血清肿瘤坏死因子仅(TNF-α)、一氧化氮(NO)和内皮素(ET)的水平变化及其临床意义。方法:用ELISA法检测91例2型糖尿病患者血清TNF-α水平,NO与ET的水平分别用硝酸还原酶法和放射免疫法测定。结果:2型糖尿病肾病各组患者TNF-α和ET水平较对照组明显升高,其中ODN组最高(P〈0.01)。而2型糖尿病肾病各组患者血清NO水平较对照组明显减少(P〈0.01)。显性糖尿病肾病患者血清TNF-α和ET呈正相关;血清TNF-α和NO、ET和NO均成负相关。结论:TNF-α、NO与ET可能参与2型糖尿病肾病的发病及病程变化过程,检测患者TNF-α、NO与ET水平可作为判断预后、指导治疗的指标。 相似文献
96.
股骨头骨骺缺血再灌注模型的建立 总被引:9,自引:1,他引:8
目的:建立缺血再灌注引起幼年兔股骨头骨骺细胞损伤的模型。方法:取12只1kg左右幼年新西兰兔,月龄,性别不限。切开兔髋关节囊,切断圆韧带,显露股骨颈,取皮筋对股骨颈进行加压,皮筋拉力约0.5kg,阻断股骨头骺动静脉血供6h、24h。松开皮筋分别恢复血供6h、24h、168h后取兔股骨头标本。结果:在取标本前进行同位素骨扫描及腹主动脉造影,证实缺血及再灌注有效。常规HE染色及胶原染色病理切片显示:单纯股骨头骨骺缺血6h骨骺骨细胞变性不明显,缺血24h组骨骺骨细胞变性;缺血24h股骨头再灌注168h后骨细胞明显坏死。结论:缺血再灌注可加重幼年兔股骨头骨骺骨细胞损伤。 相似文献
97.
Lester M. Arguelles Xiaobin Wang Binyan Wang Hakan Demirtas Jianhua Yang Zhiping Li Liuliu Wang Xue Liu Genfu Tang Houxun Xing Xiping Xu 《Archives of osteoporosis》2007,2(1-2):7-20
Introduction This report examines the relationship of body mass index (BMI), percent body fat (%BF), and bone mass in a cohort of male
and female twins recruited from Anhui province, China, ages 6–18 years—577 male pairs (mean age = 11.4) and 478 female pairs
(mean age = 11.6).
Methods Whole body bone mineral content (WBMC) in (g), whole body bone area (WBA) in (cm2), and %BF were measured using DEXA (Lunar Prodigy, USA). Regression analysis of within-pair differences was used to assess
the strength of the association, and the analysis was stratified by gender and age group, where age cut-offs were based on
ages at spermarche or menarche estimated from large population based studies in China. Males were stratified at ages before
14 and age 14–18, and females at ages prior to 12 and age 12–18.
Results Univariately, BMI and %BF were associated with WBMC and WBA in the younger males and females, and in older males; %BF was
significant only in older females. Multivariate models included both BMI and %BF. Among the younger males, age < 14, BMI and
%BF were significantly associated with WBMC and WBA. In the younger females, age < 12, %BF was only significant to WBA. In
the older age group, only BMI was significant to WBMC and WBA in females, but in males, BMI was positively associated, and
%BF was negatively associated with both bone measures.
Discussion These findings show that association between BMI and %BF and bone mass differ across gender and developmental stages, and
%BF appears to be beneficial at younger ages, but detrimental or non-beneficial at older ages of development. 相似文献
98.
目的探讨肌肉、脂肪含量与围绝经期骨质疏松妇女骨密度之间的关系。方法利用双能X线骨密度测量仪(美国,Hologic DiscoveryA型)测量门诊围绝经期妇女(90例,年龄:45~52岁(47.3±8.2))骨密度与体脂含量;同时测量登记受试者的年龄、身高、体重。结果结果显示,21%受试者腰椎和股骨骨量降低,全身脂肪含量(20675.129±5080.44)g与腰椎骨密度(0.91±0.177)g/cm2(P>0.05,r=-0.17)和髋部骨密度(0.99±0.102)g/cm2(P>0.05,r=0.158)没有相关性,肌肉含量(39790.80±6551.54)g与腰椎骨密度没有相关性(P>0.05,r=0.078),但是与髋部骨密度高度正相关(P<0.05,r=0.216)。体重(63.01±9.39)kg和腰椎(P<0.05,r=0.217)和髋部(P<0.05,r=0.305)骨密度高度正相关;BMI指数(24.6751±3.45637)与腰椎(P<0.05,r=0.244)和髋部(P<0.01,r=0.339)骨密度高度正相关。结论研究结果表明BMI指数和肌肉含量与围绝经期妇女髋部骨密度高度相关。 相似文献
99.
Objective: To investigate the anti-inflammatory effect of erythropoietin (EPO) pretreatment on cardiomyocytes exposed to hypoxialreoxygenation injury (H/R) and explore the possible mechanism.
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
100.
目的:探讨载脂蛋白A1、B基因多态性对非刨伤性股骨头坏死(avascular necrosis of the femoral head,ANFH)发生的影响.方法:应用聚合酶链反应对中国北方汉族143例ANFH患者和92例正常人分别扩增含Apo AI基因启动子-75 bp和第一内舍子 83 bp及Apo B基因Eco RI、XbaI和3-VNTR的DNA片段,限制性内切酶酶切扩增产物,琼脂糖凝胶电泳分离基因多态性.结果:Apo A1基因启动子-75 bp处,ANFH患者中A/A基因型频率明显高于正常组(P<0.01),而G/A基因型频率明显低于正常组(P<0.01).Apo AI内舍子 83 bp位点,Apo B基因Eco RI、Xba I位点和3-VNTR区域ANFH患者组和正常组基因型及等位基因频率分布无统计学差异.结论:Apo A1基因启动子区域-75bp位点A/A型可能是非创伤性股骨头坏死易感基因之一,但未能发现Apo A1第一内舍子 83 bp位点及Apo B基因Eco RI、XbaI和3-VNTR位点多态性与非创伤性股骨头坏死发生有明显的关系. 相似文献