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81.
摘要:目的 对一株南海深海来源真菌(Aspergillus sp .SCSIOW3)的抗Aβ聚集活性成分进行了分离、鉴定。方法 利用ThT荧光模型活性追踪分离 Aspergillus sp .SCSIOW3发酵产物中抗Aβ42多肽聚集活性物质,结合理化性质、波谱数据并参阅文献确定活性化合物的结构。结果 从Aspergillus sp .SCSIOW3中分离鉴定了2个具有抗Aβ42多肽聚集活性的桔霉素类衍生物:phenol A acid(1)和Penicitrinone A(2),其中化合物2在100 uM表现出与阳性对照EGCG同等程度的活性。结论 phenol A acid(1)和Penicitrinone A(2)为橘霉素衍生物,这是首次报导该类化合物的抗Aβ多肽聚集活性,具有潜在的理论和实际应用研究价值。 相似文献
82.
Karolina Gromadzka Jakub Pankiewicz Monika Beszterda Magdalena Paczkowska Beata Nowakowska Rafa Kocyowski 《Toxins》2021,13(6)
Mycotoxin exposure assessments through biomonitoring studies, based on the analysis of amniotic fluid, provides useful information about potential exposure of mothers and fetuses to ubiquitous toxic metabolites that are routinely found in food and the environment. In this study, amniotic fluid samples (n = 86) were collected via abdominal amniocentesis at 15–22 weeks of gestation from pregnant women with a high risk of chromosomal anomalies or genetic fetal defects detected during 1st trimester prenatal screening. These samples were analyzed for the presence of the most typical Aspergillus, Penicillium and Fusarium mycotoxins, with a focus on aflatoxins, ochratoxins and trichothecenes, using the LC-FLD/DAD method. The results showed that the toxin was present in over 75% of all the tested samples and in 73% of amniotic fluid samples from fetuses with genetic defects. The most frequently identified toxins were nivalenol (33.7%) ranging from <LOQ to 4037.6 ng/mL, and aflatoxins (31.4%), including aflatoxin G1, ranging from <LOQ to 0.4 ng/mL. Ochratoxin A and deoxynivalenol were identified in 26.7% and 27.9% of samples, respectively. Bearing in mind the above, the detection of mycotoxin levels in amniotic fluid is useful for the estimation of overall risk characterization with an attempt to link the occurrence of fetal abnormalities with exposure to mycotoxins in utero. 相似文献
83.
Aspergillus flavus poses a threat to society economy and public health due to aflatoxin production. aflN is a gene located in the aflatoxin gene cluster, but the function of AflN is undefined in Aspergillus flavus. In this study, aflN is knocked out and overexpressed to study the function of AflN. The results indicated that the loss of AflN leads to the defect of aflatoxin biosynthesis. AflN is also found to play a role in conidiation but not hyphal growth and sclerotia development. Moreover, AlfN is related to the response to environmental oxidative stress and intracellular levels of reactive oxygen species. At last, AflN is involved in the pathogenicity of Aspergillus flavus to host. These results suggested that AflN played important roles in aflatoxin biosynthesis, conidiation and reactive oxygen species generation in Aspergillus flavus, which will be helpful for the understanding of aflN function, and will be beneficial to the prevention and control of Aspergillus flavus and aflatoxins contamination. 相似文献
84.
Amani S. Awaad Al‐Jaber A. Nabilah Mohamed E. Zain 《Phytotherapy research : PTR》2012,26(12):1872-1877
Two new butyrolactone I derivatives: 3‐[3‐hydroxy‐4‐(3‐methyl‐but‐2‐enyl)‐phenyl]‐5‐(?4‐hydroxybenzyl)‐4‐methyl‐dihydrofuran‐2(3H)‐one (1) and (Z)‐3‐[3‐hydroxy‐4‐(3‐methyl‐but‐2‐enyl)‐phenyl]‐5‐(?4‐hydroxybenzylidene)‐4‐methyl‐dihydrofuran‐2(3H)‐one (2), in addition to the previously described (S)‐methyl‐4‐hydroxy‐2‐[4‐hydroxy‐3‐(3‐methyl‐but‐2‐enyl)‐benzyl]‐3‐(4‐hydroxy‐phenyl)‐5‐oxo‐2,5‐dihydro‐furan‐2‐carboxylic acid methyl ester (3), were identified from a strain of Aspergillus terreus Thom (Trichocomaceae) isolated from desert soil. The antifungal activities of both intra‐ and extracellular metabolites of A. terreus grown on yeast extract sucrose and malt extract media were determined. Only the secondary metabolites of A. terreus grown on yeast extract sucrose medium were active against Aspergillus fumigatus RCMB 002008. The antifungal activity of A. terreus was attributed to the presence of the compounds (1) and (2), whose minimum inhibitory concentrations (MIC) against A. fumigatus were found to be 32.00 and 16.00 µg/mL respectively. Structure elucidation was carried out using UV spectrometry, electrospray ionization mass spectrometry (ESIMS), high resolution electron impact (HREIMS) spectrometry, 1H‐ and 13 C‐NMR, proton–proton correlation spectroscopy (1H–1H Cosy), distortionless enhancement by polarization transfer (DEPT), heteronuclear single quantum coherence (HSQC) and heteronuclear multiple bond correlations (HMBC) spectroscopy. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
85.
PURPOSE: The purpose of this study was to assess the antifungal activity and renal and hepatic toxicity of amphotericin B (AmpB) following administration of Fungizone (FZ) and a heat-treated form of FZ (HFZ) to rats infected with Aspergillus fumigatus. METHODS: Infected rats were administered FZ and HFZ at a dosing regimen of 1 mg/kg i.v. once daily for 4 consecutive days. Following administration the number of colony forming units (CFUs) of Aspergillus fumigatus in different organs and serum creatinine concentrations were determined. RESULTS: FZ and HFZ had similar overall effectiveness in decreasing the total number of Aspergillus fumigatus CFUs found in all organs analyzed compared to controls. Except for the serum creatinine concentrations reported in the nontreated infected control rats, none of the treatment groups tested displayed a greater than 50% increase in serum creatinine. CONCLUSIONS: Taken together, these findings suggest that HFZ at 1 mg/kg once daily x 4 days appears to be as effective as FZ as an antifungal agent without renal toxicity. 相似文献
86.
Amhezole,A Novel Fungal Secondary Metabolite from Aspergillus terreus for Treatment of Microbial Mouth Infection 下载免费PDF全文
Amani S. Awaad Hind A. AL‐Mudhayyif Monerah R. Al‐Othman Mohamed E. Zain Reham M. El‐Meligy 《Phytotherapy research : PTR》2017,31(3):395-402
Bio‐guided fractionation of Aspergillus terreus extract leads to isolation of a novel terpenoidal secondary metabolite. The isolated compound and the total alcoholic extract of Aspergillus terreus showed a remarkable activity against microbial mouth infections; namely, Candida albicans, Lactobacillus acidophilus, Streptococcus gordonii, and S. mutan. Moreover, the Minimum Inhibitory Concentration of the isolated compound was determined and showed low values. The combination of each of the alcoholic extract of A. terreus and the isolated compound Coe‐Comfort tissue conditioner inhibited the growth of Candida albicans at concentrations of 500 and 7.81 µg/mL, respectively, Lactobacillus acidophilus at concentrations of 250 and 7.81 µg/mL, respectively, Streptococcus gordonii at concentrations of 1000 and 62.50 µg/mL, respectively, and S. mutans at concentrations of 1000 and 125 µg/mL, respectively. The oral dosing of the extract and the isolated compound did not show any significant effect on the activity of alanine aminotransferase, aspirate aminotransferase, and the levels of blood urea and serum creatinine. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
87.
1976~1991年我院收治慢性重症病毒性肝炎并发曲霉菌感染15例,感染于住院后3~112天,<30天9例。以血性痰液、胸水、腹水、脑脊液为特点。多数周围血象白细胞不增高,中性粒细胞增高,IgG增高,曲霉菌( );感染后2~10天均死亡。感染前咽部检出白色念珠菌6例,滥用抗生素者占80%。 相似文献
88.
目的 探讨肺曲霉菌病的临床特点与外科治疗原则.方法 回顾性分析医院2000年1月一2011年9月31例肺曲霉菌病的临床资料及手术治疗结果.结果 31例肺曲霉菌病患者均行手术治疗,无手术相关死亡病例,术后发生并发症7例,发生率为22.6%,其中3例出血,2例肺漏气时间延长(>7 d),2例肺不张伴肺炎;术后随访28例,随访时间为3~141个月,除1例术后考虑肺曲霉菌病复发可能,其余患者无咯血或咳血痰.结论 外科手术是肺曲霉菌病最有效的治疗方法,应根据病灶具体情况选择不同手术方式. 相似文献
89.
黄芩经侧耳菌和黑曲霉发酵后黄酮类成分的变化 总被引:1,自引:2,他引:1
目的:考察中药黄芩经侧耳菌和黑曲霉发酵后黄酮类成分变化。方法:以侧耳菌和黑曲霉发酵黄芩,应用高效液相色谱法对其黄酮类成分进行对比研究。结果:高效液相结果显示,黄芩经侧耳菌发酵后大部分黄酮类成分消失;而经黑曲霉发酵后,黄芩苷含量减少,黄芩素和汉黄芩素的含量分别是黄芩药材的2.73,5.77倍。结论:黄芩经侧耳菌和黑曲霉发酵后,苷类成分被转化为苷元或其他物质,有利于提高黄芩的生物利用度及药理活性。 相似文献
90.
目的:检测北京市零售药店僵蚕饮片表面所含真菌的种类,为临床安全用药提供参考依据。方法:培养僵蚕表面真菌,进行纯化,获得单一菌株。结合真菌菌落形态、显微结构特征、DNA条形码三种方法鉴 定僵蚕表面真菌。结果:从僵蚕饮片表面共获得真菌227株,共计10种。其中的8种真菌得到准确鉴定结果,2 种真菌为未知菌株。结论:初步了解北京市零售药店僵蚕表面真菌情况,为临床安全用药提供参考依据。 相似文献