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221.
目的 观察镁离子对培养乳鼠心肌细胞羟自由基损伤的保护作用。方法 本实验利用FeSO4/ H2O2 自由基产生体系,观察羟自由基作用于培养乳鼠心肌细胞,其上清液中乳酸脱氢酶(LDH) 和丙二醛( MDA) 含量的变化,以及镁离子对这种作用的影响。结果 (1) 羟自由基作用于培养乳鼠心肌细胞,其上清液中LDH 和MDA 的含量增加。(2) 镁离子能减少羟自由基引起的LDH 和MDA 含量的增加,且呈一定浓度、时间依赖关系。结论 羟自由基使培养乳鼠心肌细胞LDH 漏出增加及脂质过氧化终产物MDA 含量增加,镁离子对这一损伤有保护作用 相似文献
222.
丹参素对血小板聚集性及血小板膜流动性的影响 总被引:1,自引:0,他引:1
丹参素具有明显抑制由凝血酶或ADP诱导的血小板聚集作用。为进一步探索丹参素仰制血小板聚集的分子机制,本文用荧光探剂DPH标记血小板膜脂,借助荧光偏振技术,监测丹参素对血小板膜脂质流动性的影响。实验结果表明:抑制血小板聚集剂量的丹参素,能明显升高血小板膜的流动性。提示丹参素治疗冠心病有效,可能与纠正冠心病患者血小板膜的分子缺陷,增加血小板膜的流动性有关。 相似文献
223.
不同厂家的银杏叶制剂对冷水负重游泳模型小鼠保护作用的比较研究 总被引:5,自引:1,他引:5
目的观察不同厂家银杏叶制剂(天保宁片和金纳多片)对冷水负重游泳模型小鼠的保护作用.方法小鼠8℃冷水负重游泳5min,测定模型小鼠的断头喘气持续时间,并采用分光光度法测定其脑组织生化代谢的改变.结果与空白对照组相比,模型小鼠脑组织乳酸(LA)含量明显增加,乳酸脱氢酶(LDH)、Na -K -ATP酶、Ca2 -Mg2 -ATP酶活力明显降低(P<0.01);而2个EGB组均可以明显逆转模型小鼠上述生化指标的改变(P<0.05,P<0.01).结论不同厂家生产的EGB制剂均对冷水负重游泳模型动物具有保护作用,且在对模型小鼠脑组织生化代谢的影响上未显示出明显差异,故均可以作为耐缺氧研究的阳性药物. 相似文献
224.
SARS患者白细胞、淋巴细胞和乳酸脱氢酶水平分析 总被引:1,自引:0,他引:1
目的:研究严重急性呼吸综合征(SARS)患者白细胞、淋巴细胞和乳酸脱氢酶变化,探讨其与肺损伤的关系。方法:测定SARS患者激素治疗前后白细胞、淋巴细胞和血清乳酸脱氢酶含量并与健康正常人(对照组)进行比较;将SARS患者依据临床重症诊断标准分为重症组和普通组进行以上指标的比较。结果:SARS患者的白细胞、淋巴细胞绝对值均比对照组显著减少,乳酸脱氢酶明显高于对照组;经过7~10d激素治疗后的SARS患者白细胞、乳酸脱氢酶数量显著提高,淋巴细胞绝对值无显著变化。以上3项指标重症组明显高于普通组。结论:SARS患者白细胞数量、淋巴细胞绝对值显著降低,但可恢复正常;糖皮质激素治疗仅能使白细胞数量增多,而淋巴细胞绝对值未见明显改善。SARS患者的血乳酸脱氢酶升高,其水平与肺损伤的活动性相关。 相似文献
225.
Cardioprotective effect of water and ethanol extract of Salvia miltiorrhiza in an experimental model of myocardial infarction 总被引:1,自引:0,他引:1
Ethnopharmacological relevance
Salvia miltiorrhiza has long been used in the traditional Chinese formulations for the treatment of heart ischemic diseases.Aim of the study
We investigated the cardioprotective effect of purified Salvia miltiorrhiza extract (SME) in an experimental model of acute myocardial infarction.Materials and methods
Following induction of acute myocardial infarction in rats by adminstration of isoproterenol, hemodynamic and electrocardiographic parameters were monitored and recorded continuously, cardiac enzymes and parameters of oxidative stress were measured, and histopathological examination of heart tissue was performed. Experiments were performed in rats treated with SME or vehicle, as well as in those treated with Fufang Danshen Tablet (FDT) as a positive control which has previously been shown to prevent myocardial ischemia.Results
Isoproterenol-treated rats showed reductions in left ventricular systolic pressure as well as in maximum and minimum rate of developed left ventricular pressure, together with an increase in left ventricular end-diastolic pressure. They also demonstrated ST-segment elevation, together with increases in serum levels of lactate dehydrogenase, glutamic oxalacetic transaminase, creatine kinase and malondialdehyde, as well as decreases in serum activities of glutathione peroxidase and superoxide dismutase. Oral administration of SME (29.76 or 59.52 mg/kg) blunted all of the hemodynamic and biochemical changes induced by isoproterenol, as did FDT (1210 mg/kg). The protective effect of SME on isoproterenol-induced myocardial damage was further confirmed by histopathological examination.Conclusions
Our results suggest that SME affords protection against isoproterenol-induced myocardial infarction. 相似文献226.
Chiodini PL Bowers K Jorgensen P Barnwell JW Grady KK Luchavez J Moody AH Cenizal A Bell D 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2007,101(4):331-337
Malaria rapid diagnostic tests (RDTs) have performed well in a variety of studies, but recent reports have described sensitivity for Plasmodium falciparum as significantly lower than that required for operational deployment. Exposure to high temperature has been suggested as an explanation. This study assessed the temperature stability of two different Plasmodium lactate dehydrogenase (pLDH)- and three histidine-rich protein 2 (HRP2)-detecting RDTs. One HRP2 test proved insufficiently sensitive for assessment. After incubation at 35, 45 and 60 degrees C, two RDTs detecting pLDH showed a substantial fall in percentage test line positivity over time, which was not seen with the remaining two HRP-2-based RDTs. For the particular products studied, variability was high, with the pLDH-based RDTs being less sensitive than HRP2-based RDTs against the sample of P. falciparum used and more susceptible to heat-induced damage, but the reasons for this are unclear. The performance of malaria RDTs can be adversely affected at the temperatures to which they will be exposed when transported to, and used in, the rural tropics. 相似文献
227.
Antioxidant and pro-oxidant properties of pyrroloquinoline quinone (PQQ): implications for its function in biological systems 总被引:4,自引:0,他引:4
Pyrroloquinoline quinone (PQQ) is a novel redox cofactor recently found in human milk. It has been reported to function as an essential nutrient, antioxidant and redox modulator in cell culture experiments and in animal models of human diseases. As mitochondria are particularly susceptible to oxidative damage we studied the antioxidant properties of PQQ in isolated rat liver mitochondria. PQQ was an effective antioxidant protecting mitochondria against oxidative stress-induced lipid peroxidation, protein carbonyl formation and inactivation of the mitochondrial respiratory chain. In contrast, PQQ caused extensive cell death to cells in culture. This surprising effect was inhibited by catalase, and was shown to be due to the generation of hydrogen peroxide during the autoxidation of PQQ in culture medium. We conclude that the reactivities of PQQ are dependent on its environment and that it can act as an antioxidant or a pro-oxidant in different biological systems. 相似文献
228.
目的:探讨血清SCC-Ag、CYFRA21-1、LDH联合检测对肺鳞癌与肺部感染鉴别诊断的价值。方法:回顾性分析2017年1月至2018年3月北京市和平里医院消化科及呼吸科住院或门诊就诊的110例患者,其中肺鳞癌患者55例,肺部感染患者55例,使用化学发光法和速率法分别检测血清CYFRA21-1、SCC-Ag、LDH表达水平,以及肺鳞癌患者Ⅰ-Ⅳ期CYFRA21-1、SCC-Ag表达水平,经统计学处理后对比分析。结果:肺鳞癌组患者血清CYFRA21-1高于肺部感染组患者,差异有统计学意义(P<0.05);同时肺部感染组患者血清SCC-Ag表达高于肺鳞癌组,有统计学差异(P<0.05);Ⅰ期、Ⅱ期肺鳞癌组患者血清CYFRA21-1较Ⅳ期患者相比差异显著,随着肿瘤的进展,血清CYFRA21-1、SCC-Ag均有上升的趋势;肺鳞癌组患者血清LDH表达水平显著高于肺部感染组患者(P<0.01)。结论:独立的每个肿瘤标志物因其自身的特异性和敏感性,可能导致诊断的局限性,血清CYFRA21-1、SCC-Ag、LDH联合检测对肺鳞癌与肺部感染辅助鉴别诊断可能具有一定临床价值。 相似文献
229.
Xun Song Chen-yang Li Yong Zeng Hai-qiang Wu Zhong Huang Jian Zhang Rui-sha Hong Xian-xiong Chen Li-yan Wang Xiao-peng Hu Wei-wei Su Yan Li Zhen-dan He 《Journal of ethnopharmacology》2012
Ethnopharmacological relevance
Ligustrum purpurascens, named as “Ku ding cha”, has been used as a kind of functional tea in southern China for about two thousand years, which has the effects on diuresis, anti-hypertension, weight-loss and anti-inflammation.The aim of the study
This study was aimed to investigate the immune enhancement effects of the crude phenylethanoid glycosides (CPGs) from Ligustrum. Purpurascens on mice and analyze the chemical profiles of phenylethanoid glycosides in the CPGs.Materials and methods
The immune functions enhancing potential of CPGs was determined using serum hemolysin antibody, phagocytosis, splenocyte antibody production, and NK cells activity assays. The contents of five major constituents in the crude glycosides of Ligustrum purpurascens were determined by using liquid chromatography, other five glycosides were deduced according to their UV and MS spectra compared with the literature as well.Results
In the immunizing experiment, mice treated with different doses of CPGs showed an increase (p<0.01) in the haemagglutination titre compared with the control group. The increases (p<0.05) were found to be significant at doses of 440 mg/kg and 1.32 g/kg in the experiments of antibody production of spleen cells, MΦ phagocytosis of chicken RBCs and NK cell activity. Further chemical characterization yielded 10 constituents from CPGs, five glycosides were quantified by HPLC and the structures of other five compounds were speculated according to their UV and MS spectra.Conclusion
The results suggested that phenylethanoid glycosides from Ligustrum purpurascens have immunomodulatory effects on mice. 相似文献230.
SVERKER LJUNGHALL HENRIK JOBORN JONAS RASTAD G
RAN KERSTR
M 《Journal of internal medicine》1987,221(1):83-93
ABSTRACT. Ljunghall S, Joborn H, Rastad J, Åkerström G (Departments of Internal Medicine, and Surgery, University Hospital, Uppsala, Sweden). Plasma potassium and phosphate concentrations—influence by adrenaline infusion, β-blockade and physical exercise. Acta Med Scand 1987; 221:83–93. Infusion of adrenaline into healthy male subjects reduced the plasma concentrations of both potassium and phosphate to a similar extent, in a dose-dependent manner, an effect which was prevented by the administration of propranolol. Ergometer bicycling until exhaustion, which caused marked accumulation of lactic acid in the blood and reduction of pH, induced great elevations of both plasma potassium and phosphate with close relationships between the raised plasma concentrations and the reduction in pH, also during β-blockade. However, longer-term aerobic exercise, without acidosis, also caused some rise of the potassium and phosphate concentrations. During recovery from anaerobic, but not from aerobic, exercise there was a rapid decrease of the plasma potassium levels while the phosphate values normalized gradually together with pH. From measurements of the ion concentrations both in the femoral effluent of one leg, which carried out maximal isokinetic work, and in the opposite antecubital vein it could be calculated that there was for potassium, but not for phosphate, a post-exercise uptake both in the exercised muscle and in the entire organism, indicating the participation of systemic factors. 相似文献