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排序方式: 共有180条查询结果,搜索用时 15 毫秒
1.
目的观察甜菜碱对复合致病因素诱导肝纤维化大鼠的保护作用。方法复合致病因素法诱导制备肝纤维化大鼠模型,观察灌服甜菜碱对肝纤维化大鼠血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、内毒素(ET)、同型半胱氨酸(Hcy)、透明质酸(HA)、层粘连蛋白(LN)、IV胶原蛋白(IV-C)、Ⅲ型前胶原蛋白(PC-Ⅲ)及肝组织肿瘤坏死因子α(TNF-α)、一氧化氮(NO)、过氧亚硝酸盐阴离子(ONOO-)、丙二醛(MDA)的变化,并采用HE和VG染色分别观察肝损伤和肝纤维化情况。结果大鼠肝纤维化模型复制成功。给与三个剂量的甜菜碱后,肝组织病理损伤改善。反映大鼠肝功能(ALT、AST)及肝纤维化指标(HA、LN、IV-C)的水平不同程度降低。血清内毒素、肝组织NO、MDA水平亦明显降低。同时Hcy及ONOO-在中、高剂量组明显降低,而TNF-α的降低在高剂量组中也具有明显的统计学差异。结论甜菜碱可抑制复合因素诱导的大鼠肝纤维化,其作用可能是通过降低大鼠体内高同型半胱氨酸、调节炎性细胞因子和氧化应激实现的。  相似文献   
2.
Oxidative stress, apoptosis, and fibrosis may play a major role in the development of radiation‐induced liver damage. Betaine, a native compound widely present in beetroot, was reported to possess hepato‐protective properties. The objective of this study was to investigate the influence of betaine on radiation‐induced liver damage. Animals were exposed to 9 Gy applied in 3 doses of 3 Gy/wk. Betaine (400 mg/kg/d), was orally supplemented to rats after the first radiation dose, and daily during the irradiation period. Animals were sacrificed 1 day after the last dose of radiation. The results showed that irradiation has induced oxidative stress in the liver denoted by a significant elevation in malondialdehyde, protein carbonyl, and 8‐hydroxy‐2‐deoxyguanosine with a significant reduction in catalase activity and glutathione (GSH) content. The activity of the detoxification enzyme cytochrome P450 (CYP450) increased while GSH transferase (GSH‐T) decreased. The activity of the apoptotic marker caspase‐3 increased concomitant with increased hyaluronic acid, hydroxyproline, laminin (LN), and collagen IV. These alterations were associated with a significant increase of gamma‐glutamyl transferase, alkaline phosphatase and alanine and aspartate aminotransferase markers of liver dysfunction. Betaine treatment has significantly attenuated oxidative stress, decreased the activity of CYP450, enhanced GSH‐T, reduced the activity of caspase‐3, and the level of fibrotic markers concomitant with a significant improvement of liver function. In conclusion, betaine through its antioxidant activity and by enhancing liver detoxification and reducing apoptosis may alleviate the progression of liver fibrosis and exert a beneficial impact on radiation‐induced liver damage.  相似文献   
3.
目的 观察地骨皮中有效成分对高糖刺激的肾小球系膜细胞的增殖以及细胞外基质分泌的影响,研究其对糖尿病肾病的保护机制。方法 体外培养肾小球系膜细胞,分为高糖模型组(葡萄糖浓度为30mmol/L),空白对照组(葡萄糖浓度为5.5mmol/L),甜菜碱、山奈酚5个浓度剂量组(0.01、0.1、1、10、100μmol/L),用MTT法观察系膜细胞增殖情况,ELISA法观察细胞外基质分泌情况。结果 与高糖模型组比较,不同剂量甜菜碱组和山奈酚组,对高糖致肾小球系膜细胞增殖有不同程度的抑制。甜菜碱、山奈酚均能抑制细胞外基质的分泌,与高糖模型组比较有显著性差异(P<0.05~0.01)。结论 地骨皮中有效成分甜菜碱和山奈酚均具有抑制高糖刺激下系膜细胞增殖以及细胞外基质分泌的作用,推测地骨皮中有效成分具有治疗糖尿病肾病的作用。  相似文献   
4.
Moderate regular consumption of alcoholic beverages is believed to protect against atherosclerosis but can also increase homocysteine or dimethylglycine, which are putative risk factors for atherosclerosis. We aimed (1) to investigate the effect of alcohol consumption on vitamins and several metabolites involved in one-carbon metabolism; and (2) to find the most effective way of decreasing homocysteine during moderate alcohol consumption. Methods: Male volunteers (n = 117) were randomly divided into five groups: the wine-only group (control, 375 mL of white wine daily for one month) and four groups combining wine consumption with one of the supplemented substances (folic acid, betaine, and vitamins B12 or B6). Significant lowering of homocysteine concentration after the drinking period was found in subjects with concurrent folate and betaine supplementation. Vitamin B12 and vitamin B6 supplementation did not lead to a statistically significant change in homocysteine. According to a multiple linear regression model, the homocysteine change in the wine-only group was mainly determined by the interaction between the higher baseline homocysteine concentration and the change in dimethylglycine levels. Folate and betaine can attenuate possible adverse effects of moderate alcohol consumption. Dimethylglycine should be interpreted together with data on alcohol consumption and homocysteine concentration.  相似文献   
5.
目的:建立测定心脑欣片中甜菜碱含量的方法。方法采用液相色谱-串联质谱联用(LC - MS / MS)法测定甜菜碱的含量,以电喷雾离子源(ESI)正离子模式将样品离子化,多反应监测(MRM)模式下对甜菜碱( m / z 118.20→57.92和118.20→59.00)进行测定。色谱柱为 Venusil HILIC 柱(100 mm×2.1 mm,3μm),流动相为乙腈-水(80:20),流速为0.3 mL / min。结果甜菜碱进样质量浓度在4.44-177.6 ng / mL 范围内与峰面积积分值线性关系良好( r =0.9999),平均回收率为99.45%,RSD 为1.43%( n =6)。结论该方法简便、可靠、准确,可作为测定心脑欣片中甜菜碱含量的方法。  相似文献   
6.
目的研究金黄色葡萄球菌生物膜形成及甜菜碱对其抑制与分散的作用。方法采用结晶紫染色法分别测定终浓度为1.0 g/L的甜菜碱对20株金黄色葡萄球菌生物膜形成的抑制能力和甜菜碱对金黄色葡萄球菌生物膜的分散能力。结果 20株金黄色葡萄球菌均能形成生物膜,其中甲氧西林敏感的金黄色葡萄球菌(MSSA)培养24 h时形成生物膜吸光度值(A_(590 nm))达峰值,为1.99±0.53;耐甲氧西林金黄色葡萄球菌(MRSA)培养48 h时形成生物膜A_(590 nm)达峰值,为1.13±0.47。加入甜菜碱共培养后,MSSA培养24 h后生物膜A_(590 nm)为1.74±0.61,MRSA培养48 h后生物膜A_(590 nm)为0.40±0.12,与对照组相比差异均有统计学意义(t值分别为2.43和5.84,P均0.05)。当生物膜形成后加入甜菜碱,与对照组相比,MSSA和MRSA的生物膜A_(590 nm)差异无统计学意义(P0.05)。结论 1.0 g/L甜菜碱对金黄色葡萄球菌生物膜的形成具有良好的抑制作用,但不能分散已经形成的生物膜。  相似文献   
7.
8.
High‐resolution magic angle spinning (HR MAS) nuclear magnetic resonance (NMR) spectroscopy is increasingly being used to study metabolite levels in human breast cancer tissue, assessing, for instance, correlations with prognostic factors, survival outcome or therapeutic response. However, the impact of intratumoral heterogeneity on metabolite levels in breast tumor tissue has not been studied comprehensively. More specifically, when biopsy material is analyzed, it remains questionable whether one biopsy is representative of the entire tumor. Therefore, multi‐core sampling (n = 6) of tumor tissue from three patients with breast cancer, followed by lipid (0.9‐ and 1.3‐ppm signals) and metabolite quantification using HR MAS 1H NMR, was performed, resulting in the quantification of 32 metabolites. The mean relative standard deviation across all metabolites for the six tumor cores sampled from each of the three tumors ranged from 0.48 to 0.74. This was considerably higher when compared with a morphologically more homogeneous tissue type, here represented by murine liver (0.16–0.20). Despite the seemingly high variability observed within the tumor tissue, a random forest classifier trained on the original sample set (training set) was, with one exception, able to correctly predict the tumor identity of an independent series of cores (test set) that were additionally sampled from the same three tumors and analyzed blindly. Moreover, significant differences between the tumors were identified using one‐way analysis of variance (ANOVA), indicating that the intertumoral differences for many metabolites were larger than the intratumoral differences for these three tumors. That intertumoral differences, on average, were larger than intratumoral differences was further supported by the analysis of duplicate tissue cores from 15 additional breast tumors. In summary, despite the observed intratumoral variability, the results of the present study suggest that the analysis of one, or a few, replicates per tumor may be acceptable, and supports the feasibility of performing reliable analyses of patient tissue.  相似文献   
9.
10.
目的 筛选溶剂蒸发法制备九节龙皂苷I聚乳酸微球(ADS-I-PLA-MS)最佳工艺。方法 采用HPLC-ELSD测定方法,以包封率和载药量为评价指标,W/O/W溶剂蒸发法制备微球;通过单因素和正交试验设计,考察内水相九节龙皂苷I(ADS-I)甲醇溶液的质量浓度、ADS-I甲醇溶液与聚乳酸(PLA)二氯甲烷溶液体积比、PLA二氯甲烷溶液质量浓度和聚乙烯醇(PVA)体积等因素对ADS-I-PLA-MS包封率及载药量的影响。结果 溶剂蒸发法制备ADS-I-PLA-MS的最佳工艺条件为ADS-I甲醇溶液质量浓度为8 mg/mL、ADS-I甲醇溶液与PLA二氯甲烷溶液体积比为1∶13、PLA二氯甲烷溶液质量浓度为90 mg/mL、PVA体积为500 mL。结论 优选出的ADS-I-PLA-MS制备工艺合理可行。  相似文献   
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