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21.
目的 探讨人参Panx ginseng来源的细胞外囊泡(ginseng-derived nanoparticles,GDNPs)在调控肿瘤相关巨噬细胞表型及抑制黑色素瘤生长方面的潜在物质基础。方法 采用纳米颗粒跟踪分析仪、透射电镜测试及紫外-可见分光光度法全面表征GDNPs及其主要成分(蛋白质、多糖和皂苷)的含量;通过qRT-PCR和流式细胞术检测GDNPs与其含有的多糖、皂苷成分对骨髓来源巨噬细胞(bone marrow-derived macrophage,BMDM)表型的调控影响。收集不同极化程度的BMDM条件培养基(conditional medium,CM)孵育小鼠皮肤黑色素瘤B16F10细胞,CCK-8法测定不同CM处理后B16F10细胞活力,验证活性成分对肿瘤免疫微环境的调控作用;通过PMP柱前衍生法定量分析GDNPs活性成分组成。结果 透射电镜下观察GDNPs形态结构良好,含量测定结果为2.46×1011颗粒的GDNPs含有4.31 mg蛋白质、4.46 mg多糖、1.22 mg皂苷。qRT-PCR和流式细胞术实验结果显示GDNPs多糖可以逆转M2型巨噬细胞表型,向M1方向极化。GDNPs多糖诱导巨噬细胞极化后的CM显著抑制了B16F10细胞活力。PMP柱前衍生法分析GDNPs多糖成分由葡萄糖、半乳糖、阿拉伯糖组成,其物质的量比为4.72∶1.07∶2.15。结论 揭示了GDNPs中多糖成分在调控肿瘤免疫微环境的关键作用,为进一步的机制研究和临床应用提供了实验依据。  相似文献   
22.
Metformin (Met) has been shown to have pleiotropic effects such as neuroprotective, antioxidant, and anti‐inflammatory properties making that a potential candidate for the treatment of central nervous system (CNS) disorders. This study was designed to investigate the possible effect of Met on the d ‐galactose (d ‐gal)‐induced aging in ovariectomized mice. The female mice underwent bilateral ovariectomy. d ‐gal was administered orally at a dose of 500 mg/kg, and Met was administrated orally at doses of 1 and 10 mg/kg for 6 weeks. Anxiety‐like behavior was evaluated by the elevated plus‐maze. Physical power was assessed by vertical grid holding test and forced swimming capacity test. The brains were assessed for the level of superoxide dismutase (SOD) and brain‐derived neurotrophic factor (BDNF). Ovariectomy caused anxiety and declined the physical power as well as BDNF and SOD levels. d ‐gal administration in ovariectomized mice exacerbated these deleterious effects. Met hampered the anxiety‐like behavior and strengthened the physical power of d ‐gal‐treated ovariectomized mice. Met also increased the SOD and BDNF levels in the brains of d ‐gal‐treated ovariectomized animals. Based on the obtained results, we suggest Met administration as a novel therapeutic approach for the treatment of age‐related conditions in the absence of female sex hormones.  相似文献   
23.
刘峰  丁浩然  王梦月  李晓波 《中草药》2022,53(19):5991-6000
目的 研究急支糖浆多糖组分的化学成分组成、重均相对分子质量以及单糖组成,并比较不同批次急支糖浆多糖组分,为其质量控制提供依据。方法 采用比色法、高效凝胶色谱法(high performance gel permeation chromatography,HPGPC)和高效阴离子交换色谱法(high performance anion exchange chromatography,HPAEC)测定急支糖浆多糖的基本化学组成、重均相对分子质量及分散系数、单糖组成。结果 15批急支糖浆多糖的中性多糖、糖醛酸和蛋白质的平均质量分数分别为47.60%、33.38%、9.30%;重均相对分子质量及分散系数分别为11 757~26 367和1.89~2.65。15批急支糖浆多糖中均含有岩藻糖、鼠李糖、阿拉伯糖、半乳糖、葡萄糖、甘露糖、木糖、半乳糖醛酸及葡萄糖醛酸,平均质量分数分别为1.94、20.13、115.54、99.25、117.45、13.62、6.03、215.23、9.61 µg/mg,物质的量比结果为1.5:14.4:100.0:71.6:84.7:9.8:5.2:144.1:6.4。将急支糖浆与川贝枇杷糖浆、杏苏止咳糖浆、小儿热速清糖浆和小儿肺热咳喘口服液进行比较,结果发现单糖组成物质的量比结合HPAEC指纹图谱可用于急支糖浆多糖的质量控制。结论 15批急支糖浆多糖的化学组成、重均相对分子质量及单糖组成具有较高的一致性,HPAEC指纹图谱具有特异性,可用作急支糖浆多糖的质控指标。  相似文献   
24.
目的:观察补青颗粒对大鼠半乳糖性白内障的防治作用.方法:用SD大鼠复制半乳糖白内障模型.实验分为6组:空白对照组无特殊处理;模型对照组每日ip注射50% D-半乳糖溶液(10g·kg-1),连续15d,制成白内障动物模型;阳性对照组同模型组处理的同时每天给予障眼明片混悬液0.02g·kg-1 ig至实验结束;补青颗粒高、中、低剂量组处理同模型组且每天分别给予0.8,0.4,0.2 g·kg-1的剂量ig至实验结束.分别记录实验前及造模起第3,7,14天晶状体的混浊程度,实验结束时检测各组晶体超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量.结果:对照组晶状体始终透明,模型组第3天晶体开始发生混浊,补青颗粒3个剂量组晶体混浊的速度及程度在3,7,14天均明显低于模型组(P<0.05),SOD活性显著高于模型组(P<0.05),MDA含量显著低于模型组(P<0.05).结论:补青颗粒具有较好的防治大鼠半乳糖性白内障的作用.  相似文献   
25.
朱卫丰  赵加茜  刘小林  管咏梅  金晨  杨明  陈丽华 《中草药》2017,48(16):3322-3326
目的建立金水宝胶囊发酵虫草菌粉多糖的指纹图谱。方法沸水回流提取金水宝胶囊中的发酵虫草菌粉多糖,经酸水解和1-苯基-3-甲基-5-吡唑啉酮(PMP)衍生化后采用HPLC法分析,色谱条件为Phenomenex OOG-4252-EO C18色谱柱(250 mm×4.6 mm,5μm),以乙腈-0.05 mol/L磷酸盐缓冲液梯度洗脱,体积流量1 m L/min,进样量20μL,检测波长250 nm,柱温30℃。结果对组成发酵虫草菌粉多糖的11种单糖成分进行鉴别,并建立了发酵虫草菌粉多糖指纹图谱。通过指纹图谱分析10批金水宝胶囊中各单糖成分,相似度均大于0.999,无显著性差异。结论建立的发酵虫草菌粉多糖指纹图谱操作简单,专属性强,重复性好,能够客观评价金水宝胶囊的质量。  相似文献   
26.
Carbohydrates are mostly digested to glucose, fructose and galactose before absorption by the small intestine. Absorption across the brush border and basolateral membranes of enterocytes is mediated by sodium-dependent and -independent membrane proteins. Glucose and galactose transport across the brush border occurs by a Na(+)/glucose (galactose) co-transporter (SGLT1), whereas passive fructose transport is mediated by a uniporter (GLUT5). The passive exit of all three sugars out of the cell across the basolateral membrane occurs through two uniporters (GLUT2 and GLUT5). Mutations in SGLT1 cause a major defect in glucose and galactose absorption (glucose-galactose Malabsorption), but mutations in GLUT2 do not appear to disrupt glucose and galactose absorption. Studies on GLUT1 null mice and Fanconi-Bickel patients suggest that there is another exit pathway for glucose and galactose that may involve exocytosis. There are no known defects of fructose absorption.  相似文献   
27.
Xenotransplantation offers a potential solution to the shortfall in donor organs for human transplantation. This review describes the barriers to xenotransplantation and the progress that has been made towards making it a clinical reality. Data from preclinical pig-to-primate cardiac and pulmonary xenografts are highlighted.  相似文献   
28.
The anti-galactose-alpha1,3-galactose (Gal) antibody (Ab) response following pig-to-human transplantation is vigorous and largely resistant to currently available immunosuppression. The recent generation of GT-Ko mice provides a unique opportunity to study the immunological basis of xenograft-elicited anti-Gal Ab response in vivo, and to test the efficacy of various strategies at controlling this Ab response [1]. In this study, we compared the ability of non-depleting anti-CD4 and anti-CD8 to control rejection and antibody production in GT-Ko mice following xenograft and allograft transplantation. Hearts from baby Lewis rat or C3H mice were transplanted heterotopically into GT-Ko. Non-depleting anti-CD4 (YTS177) and anti-CD8 (YTS105) Abs were used at 1 mg/mouse, and given as four doses daily from day -2 to 1 then q.o.d. till day 21. Xenograft rejection occurred at 3 to 5 days post-transplantation in untreated GT-Ko recipients, and was histologically characterized as vascular rejection. Anti-CD4, but not anti-CD8, Ab treatment prolonged xenograft survival to 68 to 74 days and inhibited anti-Gal Ab as well as xeno-Ab production. In four of the five hearts from anti-CD4 mAbs-treated GT-Ko mice, we observed classic signs of chronic rejection, namely, thickened intima in the lumen of vessels, significant IgM deposition, fibrosis and modest mononuclear cell infiltrate of Mac-1+ macrophages and scattered T cells (CD8>CD4). Xenograft rejection in untreated, as well as anti-CD4- and anti-CD8-treated, recipients was associated with increased intragraft IL-6, IFN-gamma and IL-10 mRNA. C3H allografts were rejected in 7 to 9 days by untreated GT-Ko mice and were histologically characterized as cellular rejection. Treatment with anti-CD4 and anti-CD8 mAb resulted in graft survivals of >94.8 and 11.8 days, respectively. Anti-CD4 mAb treatment resulted in a transient inhibition of alloreactive and anti-Gal Ab production. The presence of circulating alloreactive and anti-Gal Abs at >50 days post-transplant was associated with significant IgM and IgG deposition in the graft. Yet, in the anti-CD4 mAb-treated group, the allografts showed no signs of rejection at the time of sacrifice (>100 days post-transplantation). All rejected allografts had elevated levels of intragraft IL-6, IFN-gamma and IL-10 mRNA, while the long-surviving anti-CD4-treated allografts had reduced mRNA levels of these cytokines. Collectively, our studies suggest that the elicited xeno-antibody production and anti-Gal Ab production in GT-Ko mice are CD4+ T-cell dependent. The majority of xenografts succumbed to chronic rejection, while allografts survived with minimal histological change, despite elevated levels of circulating alloAbs. Thus, immunosuppression with anti-CD4 mAb therapy induces long-term survival of allografts more effectively than to xenografts.  相似文献   
29.
D-半乳糖在小鼠上诱导的拟脑老化效应   总被引:74,自引:0,他引:74  
小鼠scD-半乳糖50和500mg·kg-1·d-1×6wk,游泳迷宫作业训练成绩降低:皮层和海马神经元C-fos,H-ras原癌基因杂交效率和核仁组织区染色能力下降,神经元核浆面积比值,细胞密度,总蛋白和核酸含量下降。上述结果与老龄小鼠所见吻合,提示在D-半乳糖诱导下产生了拟脑老化效应。  相似文献   
30.
Summary. The present study was undertaken in order to measure the effect of hyperosmotic solutions on portal and hepatic blood flow. In five anaesthetized pigs without arterial blood supply to the liver, portal blood flow rate was measured (electromagnetic flowmeter) during 5 min lasting intravenous infusions of hyperosmotic galactose (50%, 84–100 ml) and mannitol (25%, 100 ml), with physiological saline (100 ml) as control. Portal blood flow increased to a peak value of (39% [P= 0–06] galactose and 37%, [P= 0–06], mannitol) soon after stop of the hyperosmotic infusion. For galactose the change ended somewhat earlier than for mannitol. Saline induced a minor increase (15%). Similarly, increments of, on average, 144% of the hepatic blood flow rate was seen in six patients with cirrhosis, following infusion of hyperosmotic galactose, the increase being more pronounced than in the pigs. The causes for these osmotic effects are not known, but they have to be taken into consideration in studies of the portal and hepatic blood flow.  相似文献   
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