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1.
目的 通过观察黄芩苷对乳腺癌组织毛细血管通透性(Capillary Vessel Permeability,CVP)、赖氨酰氧化酶(Lysyl Oxidase,LOX)及血清丙二醛(Malondialdehyde,MDA)等相关指标的影响,探讨黄芩苷可能的抗乳腺癌作用机制。方法 通过在裸鼠皮下接种MDA-MB-231乳腺癌细胞株建立乳腺癌移植瘤模型;实验分为模型组、黄芩苷组、阿霉素组、黄芩苷+阿霉素组。于接种第7日开始:黄芩苷组每天灌胃黄芩苷水溶液(100 mg·kg-1),连续14天;阿霉素组每3天腹腔注射一次阿霉素(5mg·kg-1),共用药5次;模型组每天灌胃生理盐水(10 mL·kg-1),连续14天;黄芩苷+阿霉素组每天灌胃黄芩苷水溶液(100 mg·kg-1),连续14天,并每3天腹腔注射一次阿霉素5 mg·kg-1,共5次。给药期间监测移植瘤体积;紫外可见分光光度计620 nm下测OD值来反映黄芩苷对肿瘤毛细血管通透性的影响;硫代巴比妥酸(Thiobarbituric acid,TBA)比色法检测黄芩苷对裸鼠血清中丙二醛(MDA)的影响;免疫组化染色法检测乳腺癌组织中赖氨酰氧化酶(LOX)的表达情况。结果 ①与模型组比较,黄芩苷组、阿霉素组、黄芩苷+阿霉素组瘤体重量均明显减轻(P<0.05);黄芩苷+阿霉素组瘤体重量较阿霉素组明显减轻(P<0.05)。②与模型组比较,黄芩苷组降低乳腺癌组织毛细血管的通透性,而阿霉素组则增加肿瘤组织中毛细血管的通透性,差异均具有统计学意义(P<0.05)。③黄芩苷组能够明显抑制荷瘤裸鼠血清MDA的表达,与模型组比较差异有显著统计学意义(P<0.01);阿霉素组促进MDA的表达,与模型组比较差异有统计学意义;黄芩苷+阿霉素组促进MDA的表达,与模型组比较差异无统计学意义。④与模型组比较,黄芩苷组裸鼠乳腺癌组织LOX的表达显著下调(P<0.01),阿霉素组肿瘤组织中LOX表达增加(P<0.05);黄芩苷+阿霉素组能下调裸鼠乳腺癌组织LOX的表达,与模型组比较差异无统计学意义。结论 黄芩苷能够明显抑制乳腺癌移植瘤的生长,其机制可能与黄芩苷降低肿瘤组织毛细血管的通透性,抑制裸鼠血清中丙二醛、乳腺癌组织中赖氨酰氧化酶的表达,从而改变肿瘤缺氧微环境有关。  相似文献   
2.
Background & objectiveTo date, cinnamon supplementation has been investigated due to its antioxidant and anti-inflammatory properties. Several studies have confirmed the effects of cinnamon supplementation on several markers of cardiometabolic health. However, the effects of cinnamon supplementation on inflammation and oxidative stress levels warrant further investigation. Hence, the current meta-analysis was conducted to elucidate the impact of cinnamon supplementation on biomarkers of inflammation and oxidative stress.MethodsTo perform this systematic review and meta-analysis, we employed the Preferred Reporting Items of Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The systematic search of available clinical trials was performed using the following databases: PubMed/MEDLINE, Scopus, Cochrane Library, Web of Science, Embase, and Google Scholar, up to January 2020.ResultsAfter removing the duplicates, 1145 studies were eligible for analysis and 12 of them were included in the meta-analysis. The dose of cinnamon powder investigated in the included trials ranged from 1.5 to 4 g/day. Cinnamon supplementation resulted in a significant reduction of C-reactive protein (CRP) (weight mean difference (WMD): −2.22 mg/L, 95 % CI: −3.74, −0.69, P = 0.004) and malondialdehyde (MDA) (WMD: −0.79 mmol/L, 95 % CI: −1.28, −0.29, P = 0.002), and marginally statistical significant decrease in interleukin-6 (IL-6) (WMD: −1.48 pg/mL, 95 % CI: −2.96, −0.01, P = 0.049). Moreover, it was associated with an increase in the total antioxidant capacity (TAC) (WMD: 0.34 mmol/L, 95 % CI: 0.04, 0.64, P = 0.026). However, the levels of intercellular adhesion molecule-1 (ICAM-1) (WMD: 1.53 ng/mL, 95 % CI: −12.03, 15.10, P = 0.82) did not change significantly following cinnamon supplementation.ConclusionsCinnamon supplementation may be an adjuvant for reducing inflammation and oxidative stress levels in humans.  相似文献   
3.
Objective: Irisin, mostly known as an exercise-induced fat browning myokine, has been recently detected in several cancer cells, and its potential for being utilized as a biomarker for early diagnosis of some cancers, such as Gastric cancer (GC), is the subject of speculation. The present study aims to compare serum irisin levels in GC patients and healthy controls and assess the interrelation between irisin and oxidative stress markers. Methods: In this case-control study, 22 newly diagnosed GC patients and 29 healthy controls were recruited based on the inclusion criteria. Serum levels of irisin were quantified in duplicates by ELISA. Oxidative stress indices, including total antioxidant power in sera, thiol group, malondialdehyde, and superoxide dismutase concentrations, were also measured in both groups. An independent-sample t-test was used to compare the means between the two studied groups. Results: Serum levels of irisin were significantly higher in the GC group compared with those of their healthy counterparts (p =0.032). No significant differences were observed between the two groups in terms of the serum total antioxidant power or the oxidative stress marker, including MDA, thiol groups, and SOD concentration in sera. Furthermore, there was no significant association between irisin, FRAP, the Thiol group, and the SOD activity. Conclusion: According to the finding, the increased serum levels of irisin in GC patients can play a potential role in the early diagnosis of the GC patients; hence, this peptide can be employed as a new diagnostic indicator of GC.  相似文献   
4.
【摘要】 目的 探讨外源性胆绿素对中波紫外线(UVB)照射的HaCaT细胞光损伤的保护作用。方法 将HaCaT细胞分为加入0、0.1、1、10 μmol/L胆绿素并照射UVB的UVB组、0.1 μmol/L UVB组、1 μmol/L UVB组、10 μmol/L UVB组及不做处理的对照组。UVB照射剂量为30 mJ/cm2,照射后继续培养24 h,分别检测细胞活性氧(ROS)水平、超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量,ELISA法检测各组细胞的炎症因子白细胞介素6(IL-6)、IL-8水平。多组间均数比较采用单因素方差分析,组间两两比较采用LSD-t检验。结果 UVB组、0.1 μmol/L UVB 组、1 μmol/L UVB组、10 μmol/L UVB组、对照组细胞ROS水平(3 613.33 ± 206.61、2 958.67 ± 193.87、2 678.33 ± 178.24、2 274.67 ± 118.81、1 905.67 ± 250.25)、SOD活力(24.41 ± 1.78、28.96 ± 2.21、29.75 ± 1.75、30.19 ± 2.29、37.52 ± 2.31)、MDA含量(5.61 ± 0.32、5.46 ± 0.55、4.65 ± 0.22、2.55 ± 0.93、1.31 ± 0.05)、IL-6水平、IL-8水平差异均有统计学意义(F值分别为 34.02、57.36、214.09、29.73、11.40,均P < 0.05),UVB组ROS水平、MDA含量及IL-6、IL-8水平均高于另4组(均P < 0.05),SOD活力均低于另4组(均P < 0.05)。结论 外源性胆绿素减轻UVB引起的HaCaT细胞的氧化损伤、减轻炎症反应和抑制脂质过氧化作用,对细胞光损伤有一定的保护作用。  相似文献   
5.
The effects of a high-cholesterol diet in the presence and absence of defibrotide, a single-stranded polydeoxyribonucleotide compound, on the lipid peroxidation product malondialdehyde, endogenous antioxidant enzymes catalase, glutathione peroxidase, and the antioxidant thiol compound GSH were investigated. Forty male New Zeland white rabbits were divided into four groups each consisting of 10 rabbits. Group I received a regular rabbit chow diet and group II 1% cholesterol plus regular chow, group III was given defibrotide (60 mg/kg per day p.o. in water) and was fed with regular chow, and group IV received defibrotide plus 1% cholesterol for 9 weeks. Blood cholesterol and malondialdehyde, catalase, glutathione peroxidase, and GSH were determined before starting the experimental diet regimen (basal). After 9 weeks, the same parameters were determined in blood, aorta, and brain tissues (end -experiment). Aortic tissue was examined under a light microscope for morphological alterations indicative of atherosclerosis. The increase in serum total cholesterol was greater in group II than group IV. Plasma malondialdehyde in group II was higher than in group III. Brain malondialdehyde in group II was higher than all other groups, and aortic malondialdehyde in this group was higher than group I and III. Serum catalase activity decreased in group II and increased in group III, compared with basal values. Brain catalase activity in group I was higher than group II, and aorta catalase in group IV was higher than in group I and III. Blood glutathione peroxidase activity in group III and IV was higher than basal. GSH concentrations decreased significantly in the cholesterol-fed groups (group II and IV). Histological alterations in the cholesterol-fed groups were more pronounced in group II. The increased levels of malondialdehyde in plasma, aorta, and brain tissue of group II suggest a role of oxygen free radicals in the pathogenesis of cholesterol-induced atherosclerosis. The higher malondialdehyde values in the brain tissues of animals in group II compared with group IV suggest a protective role of defibrotide in the brain against lipid peroxidation in the oxidant stress of cholesterol-induced atherosclerosis. Increased catalase activities in the blood and aortic tissues and increased glutathione peroxidase activities in the blood of rabbits receiving defibrotide suggest an induction of these antioxidant enzyme activities by defibrotide. These results imply that anti-atherosclerotic, anti-ischemic effects of this drug may be due to the beneficial effects on the oxidant-antioxidant balance of various tissues.  相似文献   
6.
目的:观察8Hz,130dB次声作用于大鼠不同时间后,大脑皮层脂质过氧化相关指标的变化,以探讨次声引起脑损伤的机理。方法:将35只Ⅱ级、雄性、SD大鼠随机分为对照组和次声作用7d,14d,21d,28d组五组,用8Hz,130dB次声作用,每天1次,每次2h,各组于最后一次作用结束后0.5-1h内取大脑皮层,制成10%的组织匀浆测定GSH-Px活性,MDA含量和SOD活性的变化。结果:与对照组相比,大鼠大脑皮层GSH-Px活性在7d组无显著性变化(P>0.05),在14d组、21d组、28d组和显著性升高(P<0.05);MDA含量在7d组、14d组有显著怀升高(P<0.05),21d组、28d组恢复至对照组水平(P>0.05);SOD活性有下降的趋势,但无显著性意义(P>0.05)。结论:次声作用后,引发大鼠大脑皮层组织的脂质过氧化-抗氧化反应,造成脑组织的损伤。  相似文献   
7.
目的:通过检测高原地区部队官兵腰椎间盘突出症(lumbar disc herniation,LDH)患者血清中超氧化物歧化酶(SOD)的活力值及丙二醛(MDA)含量,探讨低氧环境下氧自由基对腰椎间盘突出症发病的影响。方法:采集腰椎间盘突出症患者血清标本作为患病组,共27例,随机抽取高原驻军健康机体血清标本27例为对照组,服役年限均为2~5年。取入伍1周的新兵血清标本27例为标准组进行比较。结果:27例腰椎间盘突出症患者血清中SOD活力值低于对照组高于标准组(P<0.05)。患病组血清中MDA高于对照组及标准组(P<0.05)。结论:高原地区部队官兵腰椎间盘突出症患者存在着不同程度的氧自由基代谢失衡,主要表现为清除超氧阴离子自由基的SOD活性下降,氧自由基含量的升高。氧自由基是加速椎间盘退变和致痛的重要因素。  相似文献   
8.
目的 检测模拟高原潜水实验中潜水员血清氧化损伤产物含量以及促红细胞生成素和抗氧化酶系活性变化,探讨高海拔潜水对人体氧化损伤的影响.方法 模拟高原潜水实验人员进舱前、潜水停留过程中、潜水结束后及出舱后采静脉血,检测血清丙二醛(MDA)含量、促红细胞生成素(EPO)水平、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性以及总抗氧化活性(TAOC).结果 实验前、中、后MDA含量在[(3.31±1.35)~(6.98±3.52)]μmol/L范围内波动,各种抗氧化酶活性水平基本在正常范围内.血清MDA含量、GSH-Px活性与环境氧分压及暴露时间存在相关性,在高氧-低氧交替变化的环境中血清EPO水平与SOD和CAT呈反向相关趋势.结论 本次实验条件下低-高氧环境的反复变化未对4名潜水员造成可检测到的氧化损害.  相似文献   
9.
目的 通过观察高压氧(HBO)对局灶性脑缺血再灌注(CI/R)所致脑组织细胞线粒体过氧化损伤及凋亡的影响,探讨HBO对抗CI/R损伤的作用及其机制.方法 将80只SD大鼠按随机数字表法分为4组:假手术对照组(假手术组)8只,CI/R组、CI/R后常压吸氧(CI/R+N)组、CI/R后HBO治疗(CI/R+HBO)组,每组24只.采用大脑中动脉内线栓阻断法(MCAO)制备大鼠局灶性CI/R模型.(假手术组)操作步骤相同,但仅将线栓插入大脑中动脉10 mm后退出.假手术组、CI/R组术后不予任何处理,CI/R+N组术后30 min常压下吸纯氧,CI/R+HBO组术后30 min行常规HBO处理,均为60 min/次,1次/12 h.每组于CI/R术后12、24、48 h各处死8只大鼠,取CI/R损伤灶脑组织,采用比色法检测脑组织内线粒体超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量,流式细胞技术检测脑细胞凋亡率.结果 CI/R组术后12、24、48 h SOD活性持续下降,显著低于假手术组[(139.21±11.52与(214.13±13.76)、(127.41±12.36)与(214.13±13.76)、(112.33±11.69)与(214.33±13.76)×10-6U/g)](均P<0.01);CI/R+N组12、24、48 h SOD活性[(157.16±8.91)、(146.33±9.93)、(133.49±10.21)×10-6 U/g)]明显高于CI/R组(均P<0.05),CI/R+HBO组12、24、48 h SOD活性[(176.80±12.35)、(169.43±12.41)、(161.56±13.81)×10-6 U/g)]显著高于CI/R组和CI/R+N组(均P<0.05),显示CI/R后HBO治疗能有效地保护线粒体SOD的活性.CI/R组MDA含量术后持续增高,12、24、48 h显著高于假手术组(均P<0.01).CI/R+N组MDA含量术后12、24、48 h时均低于CI/R组,但差异均无统计学意义(均P>0.05);CI/R+HBO组MDA含量术后24、48 h时均显著低于CI/R组(均为P<0.01)和CI/R+N48 h组(均P<0.05),显示HBO治疗可有效抑制MDA的产生.CI/R组术后12、24、48 h脑细胞凋亡率持续增高,均显著高于假手术组(均P<0.01);CI/R+N组术后24、48 h组脑细胞凋亡率均低于CI/R组,但差异无统计学意义(均P>0.05);CI/R+HBO组术后24、48 h脑细胞凋亡率均显著低于CI/R组(均P<0.05)和CUR+N 48 h组时(均P<0.05);显示HBO治疗能有效降低CI/R后脑细胞凋亡率.结论 HBO治疗可明显增强细胞线粒体的稳定性,有效保护CI/R后脑组织线粒体SOD的活性,减轻大鼠CI/R所致线粒体过氧化损伤及脑细胞凋亡,较常压吸氧具有更显著的脑保护作用.  相似文献   
10.
目的 探讨胺碘酮联合磷酸肌酸钠对窒息兔心肺复苏( cardiopulmonary resuscitation,CPR)后心肌形态学、丙二醛( malondialdehyde,MDA)含量及超氧化物歧化酶(superoxide dismutase,SOD)活性的影响.方法 采用窒息法制作CPR模型.选取健康日本长耳大白兔40只,完全随机分为A组(假手术组)、B组(生理盐水组)、C组(胺碘酮5 mg/kg组)、D组(磷酸肌酸钠100 mg/kg组)、E组(胺碘酮5 mg/kg联合磷酸肌酸钠100 mg/kg组),每组8只.CPR后6h处死兔,光镜及电镜下观察心肌形态学变化,检测心肌MDA含量、SOD活性.结果 光镜下心肌组织病理改变显示:E组心肌损伤轻于C组和D组,C组和D组又轻于B组.电镜下心肌超微结构显示:A组兔的心肌线粒体完整,肌丝排列整齐,明暗带清晰;B组兔的心肌线粒体部分水肿、空泡化,线粒体嵴断裂,肌丝排列紊乱,明暗带分界不清;C组兔心肌少数线粒体空泡化、嵴断裂,肌丝排列尚整齐,明暗带显示不清;D组兔心肌少数线粒体空泡化、嵴断裂,明暗带清晰;E组兔心肌线粒体完整,个别线粒体水肿、嵴断裂,明暗带清晰可见.B组、C组、D组兔心肌MDA含量(2.45±0.41,1.65±0.18,1.71±0.17)较A组(0.98±0.22)升高,差异有统计学意义(P<0.05);B组兔心肌MDA含量显著高于C组和D组,C组和D组又高于E组,差异有统计学意义(P<0.05);E组(1.21±0.55)与A组比较差异无统计学意义.B组、C组、D组和E组兔心肌SOD活性(16.2±0.9,17.9±1.0,18.2±0.6,19.8±1.4)较A组(21.4±2.1)减低,差异有统计学意义(P<0.05);B组心肌SOD活性低于C组和D组,C组和D组又低于E组,差异有统计学意义(P<0.05).结论 胺碘酮联合磷酸肌酸钠能减轻CPR后心肌损伤;部分抑制CPR后的过氧化反应,减轻脂质过氧化损伤,可能是胺碘酮联合磷酸肌酸钠心肌保护作用的主要机制之一.  相似文献   
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