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21.
亚硒酸钠和硒蛋氨酸的毒性比较   总被引:3,自引:0,他引:3  
目的 比较亚硒酸钠和硒蛋氨酸毒性差异以及探讨硒中毒的指标。方法 将断乳Wistar大鼠随机分为 7组 ,每组 14只 ,雌雄各半。其中一组为对照组 ,另外六组分别给予含硒 3、6、10mg kg的亚硒酸钠或硒蛋氨酸饲料 ,于第 12周将其处死。结果 当饲料硒水平达到 3mg kg时 ,动物肝脏出现病理变化 ,在Se6mg kg时 ,体重才出现下降。饲料硒水平为 6、10mg kg时 ,同一饲料硒水平的亚硒酸钠组大鼠体重小于硒蛋氨酸组。饲料硒水平为 3、6mg kg时 ,硒蛋氨酸组大鼠的肝脏病理改变轻于亚硒酸钠组 ,雄性大鼠轻于雌性。亚硒酸钠组较硒蛋氨酸组或雌性大鼠较雄性大鼠在肝脏体重比方面变化更为明显。除雌性大鼠肝脏谷胱甘肽过氧化物酶 (GPX)活性随硒水平升高而降低外 ,其它补硒各组肝、红细胞、血浆GPX活性具有随硒水平的升高而升高的趋势。结论 大鼠硒中毒的剂量为Se 3mg kg,硒蛋氨酸的毒性小于亚硒酸钠 ,雌性大鼠对硒毒性更为敏感  相似文献   
22.
Xa21转基因大米对大鼠致畸作用的实验研究   总被引:6,自引:0,他引:6  
目的 观察Xa2 1转基因大米对大鼠胚胎生长、发育的影响。方法 将初断乳Wistar大鼠按雌雄分别随机分为 4组 :转基因大米组、非转基因大米组、AIN93G对照组和敌枯双阳性对照组。单笼喂养 ,饲相应鼠料 ,喂满 90天 ,雌雄合笼。观察母鼠和胎鼠的生长发育情况。结果 转基因大米组孕鼠增重、活胎体重、身长、尾长均显著高于阳性对照组 ,而死胎数、吸收胎数、畸形率 (外观、内脏、骨骼 )均显著低于阳性对照组。转基因大米组与非转基因大米组、AIN93G对照组相比 ,所有观察指标均无统计学差异。结论 转Xa2 1基因大米与非转基因大米相比 ,对大鼠受孕率、胚胎生长发育无显著性差异。  相似文献   
23.
鹿茸口服液对抗氧化酶的影响   总被引:1,自引:0,他引:1  
目的:研究鹿茸口服液对青年及老年小鼠的抗氧化作用.方法:灌服鹿茸口服液后,测定小鼠SOD、CAT和GSHpx活性及MDA含量.结果:鹿茸口服液对老年小鼠SOD活性增强和MDA含量降低作用均明显强于对青年小鼠,并能增强老年小鼠肝CAT和GSHpx活性.结论:鹿茸口服液对老年小鼠具有抗氧化作用.  相似文献   
24.
To develop a hyaluronic microsphere with the improved oral bioavailability of poorly water-soluble cyclosporin A (CsA), the microspheres were prepared with varying ratios of sodium hyaluronate (HA)/sodium lauryl sulfate (SLS)/CsA using a spray-drying technique. The effects of HA and SLS on the dissolution and solubility of CsA in microspheres were investigated. The CsA-microsphere prepared with HA/SLS/CsA at the ratio of 4/2/1 gave the highest solubility and dissolution rate of CsA among those formulae tested. As solubility and dissolution rate of CsA were increased about 17- and 2-fold compared to CsA powder, respectively, this CsA-microsphere was selected as an optimal formula for oral delivery in rats. The CsA-microsphere and Sandimmun neoral sol gave significantly higher blood levels compared with CsA powder alone. Moreover, the AUC, T(max) and C(max) values of CsA in CsA-microsphere were not significantly different from those in Sandimmun neoral sol in rats, indicating that CsA-microsphere was bioequivalent to the commercial product in rats. Our results demonstrated that the CsA-microsphere prepared with HA and SLS, with improved bioavailability of CsA, might have been useful to deliver a poorly water-soluble CsA.  相似文献   
25.
BackgroundEndometrial stromal tumours are uncommon tumours of the uterus. They mainly occur in perimenopausal women. Tumours with typical clinicopathological features do not usually pose diagnostic problems. However, rare clinicopathological features can occur, and clinicians without significant experience may have difficulty diagnosing these tumours and managing these patients.MethodsHerein, we report a case of endometrial stromal sarcoma that occurred in a 25‐year‐old woman. The pathological features, immunophenotype, treatment and prognosis were discussed.ResultsThe tumour revealed morphological heterogeneity, and there were similar proliferative‐type endometrial stromal cells, an extensive amount of mature adipose tissue, and prominent rhabdomyoblastic and smooth muscle cells. Histopathological and immunohistochemical studies confirmed low‐grade endometrial stromal sarcoma with smooth muscle, adipocytic and rhabdomyoblastic differentiation (approximately 60% were differentiated tissues). The final treatment of the tumour was total abdominal hysterectomy with bilateral salpingo‐oophorectomy. There was no evidence of recurrence for 109 months postoperatively.ConclusionsWe found that low‐grade endometrial stromal tumours with extensive adipocytic and prominent rhabdomyoblastic differentiation are misdiagnosed because they are infrequent. They must be differentiated from rhabdomyosarcoma with accurate identification of adipocytes, and long‐term follow‐up is needed.  相似文献   
26.
目的:研究基质金属蛋白酶14(mmp-14)与CD34在≤35岁乳腺癌、乳腺良性肿瘤、乳腺增生症及乳腺癌旁组织患者中的表达及临床意义。方法采用免疫组织化学方法对30例乳腺癌、30例乳腺良性肿瘤、30例乳腺增生症及30例癌旁组织中乳腺终末导管及腺泡上皮细胞患者的mmp-14表达情况及CD34标记的间质血管数目进行检测。结果 mmp-14在4组导管及腺泡上皮细胞中的表达情况:乳腺癌组mmp-14高表达,与其他3组两两比较差异具统计学意义(P<0.05)。CD34在4组中标记间质血管数目的情况:乳腺增生症组和乳腺癌组血管增生数目均高于良性肿瘤组,差异有统计学意义(P<0.05)。结论乳腺终末导管及腺泡上皮细胞mmp-14的高表达和CD34标记的间质血管数目增加与青年乳腺癌的演变过程密切相关,有望成为青年乳腺癌早期诊断和治疗可靠的临床指标。  相似文献   
27.
The objectives of this study were to investigate the radical-scavenging activity and protective potential of Sophora flavescens from oxidative damage by the radical generator 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) in renal epithelial LLC-PK(1) cells and to identify the active components using the bioassay-linked fractionation method. The MeOH extract and fractions of CH(2)Cl(2), BuOH, and H(2)O from S. flavescens showed 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging effects in a dose-dependent manner (p<0.01),whereas only the BuOH and CH(2)Cl(2) fractions showed protective effects against LLC-PK(1) cellular damage induced by AAPH in a dose-dependent manner (p<0.01). In particular, the BuOH fraction had the most effective (p<0.05) antioxidative capacity. Employing a bioassay-linked HPLC/MS method, the active constituents from the BuOH fraction of S. flavescens were isolated and characterized as sophoraflavanone G and kurarinone with potent antioxidant effects against the DPPH radical, with IC(50) values of 5.26 and 7.73 microg/ml, respectively. Moreover, the compounds dose dependently recovered cell viability decreased by AAPH treatment (p<0.01), suggesting their protective roles against cellular oxidative damage. The results of this study suggest that S. flavescens has excellent antioxidative and kidney-protective potential and that flavonoids from S. flavescens, i.e., sophoraflavanone G and kurarinone, are the active constituents.  相似文献   
28.
目的:观察卵磷脂络合碘与复方血栓通胶囊在治疗不同病程玻璃体混浊时的疗效及其对比。方法:发病时间不等的玻璃体混浊患者随机分配接受卵磷脂络合碘或复方血栓通胶囊治疗。治疗前及治疗30,60d后分别行裂隙灯、眼底镜等检查,观察玻璃体混浊情况和视力变化,并评定混浊等级。结果:治疗30d后,新发组和短期组血栓通胶囊治疗有效率均显著低于卵磷脂络合碘治疗组(P<0.05);治疗60d后,陈旧组经血栓通治疗有效率显著高于卵磷脂络合碘治疗组(P<0.05),且各组总有效率均显著高于治疗30d的有效率(P<0.05)。长期组、陈旧组与新发组相比,经两种药物治疗后的总有效率均明显降低(P<0.01)。结论:卵磷脂络合碘对发病时间较短的玻璃体混浊治疗效果优于复方血栓通胶囊,而复方血栓通胶囊治疗慢性陈旧性玻璃体混浊效果理想。对玻璃体混浊一经诊断尽早施治,并适当延长治疗时间,有助于提高治疗效果。  相似文献   
29.
Cornuside is an iridoid glycoside from Cornus officinalis, with the activities of anti-inflammatory, antioxidant, anti-mitochondrial dysfunction, and neuroprotection. In the present research, a triple-transgenic mice model of AD (3 × Tg-AD) was used to explore the beneficial actions and potential mechanism of cornuside on the memory deficits. We found that cornuside prominently alleviated neuronal injuries, reduced amyloid plaque pathology, inhibited Tau phosphorylation, and repaired synaptic damage. Additionally, cornuside lowered the release of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nitric oxide (NO), lowered the level of malondialdehyde (MDA), and increased the activity of superoxide dismutase (SOD) and the level of glutathione peroxidase (GSH-Px). Cornuside also significantly reduced the activation of astrocytes and modulated A1/A2 phenotypes by the AKT/Nrf2/NF-κB signaling pathway. We further confirmed that LY294002 and Nrf2 silencing could block the cornuside-mediated phenotypic switch of C6 cells induced by microglia conditioned medium (MCM) in response to lipopolysaccharide (LPS), which indicated that the effects of cornuside in astrocyte activation are dependent on AKT/Nrf2/NF-κB signaling. In conclusion, cornuside may regulate the phenotypic conversion of astrocytes, inhibit neuroinflammation and oxidative stress, improve synaptic plasticity, and alleviate cognitive impairment in mice through the AKT/Nrf2/NF-κB axis. Our present work provides an experimental foundation for further research and development of cornuside as a candidate drug for AD management.  相似文献   
30.
目的:探讨白藜芦醇对脂多糖(LPS)诱导的小胶质细胞激活时所分泌的一氧化氮(NO)和肿瘤坏死因子-α(TNF-α)的影响。方法:采用LPS诱导的小胶质细胞活化模型,用ELISA法测定细胞外液中的炎症介质NO和TNF-α的含量。结果:LPS能高度激活小胶质细胞并且能使NO和TNF-α分泌增加,白藜芦醇明显抑制NO和TNF-α的含量。结论:白藜芦醇有抑制炎症介质NO和TNF-α的分泌作用。  相似文献   
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