首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   415篇
  免费   17篇
  国内免费   12篇
耳鼻咽喉   1篇
儿科学   6篇
基础医学   84篇
口腔科学   1篇
临床医学   16篇
内科学   41篇
皮肤病学   37篇
神经病学   1篇
特种医学   2篇
外科学   10篇
综合类   57篇
预防医学   34篇
药学   123篇
中国医学   17篇
肿瘤学   14篇
  2024年   4篇
  2023年   6篇
  2022年   8篇
  2021年   14篇
  2020年   6篇
  2019年   5篇
  2018年   11篇
  2017年   11篇
  2016年   14篇
  2015年   9篇
  2014年   13篇
  2013年   31篇
  2012年   28篇
  2011年   24篇
  2010年   26篇
  2009年   19篇
  2008年   21篇
  2007年   27篇
  2006年   27篇
  2005年   18篇
  2004年   13篇
  2003年   8篇
  2002年   13篇
  2001年   8篇
  2000年   11篇
  1999年   9篇
  1998年   7篇
  1997年   5篇
  1996年   4篇
  1995年   8篇
  1994年   5篇
  1993年   6篇
  1992年   7篇
  1991年   2篇
  1990年   5篇
  1989年   2篇
  1988年   3篇
  1987年   4篇
  1985年   1篇
  1981年   1篇
排序方式: 共有444条查询结果,搜索用时 15 毫秒
1.
Objective To investigate the clinical characteristics and imaging manifestations of AIDS complicated with disseminated Penicillium marneffei (PM) infection. Methods A total of 12 patients with AIDS complicated with disseminated PM infection were collected and the symptoms, signs, laboratory examination results and image manifestations of these patients were analyzed retrospectively. Results (1) The diagnosis of PM infection in all the 12 cases were confirmed by peripheral blood culture. All the 12 cases (100%) had irregular fever (38-41℃) and enlarged lymph nodes, 8 cases (66%) had skin rashes; 8 cases (66%) had hepatomegaly; 9 cases (75%) had splenomegaly while 8 cases (66%) had anemia. (2) Imaging manifestation: Five cases manifested bilateral pulmonary disseminated miliary nodular shadows or lattice signs; 1 case showed enlarged hilar lymph node and 2 cases showed patchy shadow with pleuritis. One case presented sub-pleural curve line shadow at the posterior part of the right lower lung, and adhesion between the intestinal wall and intestinal mesentery in mass form in the abdomen by CT examination. Conclusion Patients suffering from AIDS (CD4 T lymphocytes 〈50/μ L) with impaired immunity might be susceptible to complication of disseminated PM infection, which presents mainly damage of multiple organs and symptoms such as fever; enlargement of liver, spleen and lymph nodes, as well as specific skin maculopapular rashes. Imaging manifestations in the lungs were revealed as miliary nodular shadows and lattice-like shadows. Intensified abdominal CT might reveal presence of several enlarged postperitoneal lymph nodes and intestinal adhesion in shape of "cakes".  相似文献   
2.
Summary The Aspergillus nidulans acetamidase gene (amdS) has been used to transform Penicillium chrysogenum at low frequency. Several transformants were tested and shown to be mitotically stable. Southern blot analysis indicated that transforming DNA had integrated into the chromosomal DNA, possibly at multiple sites.  相似文献   
3.
A high frequency transformation system has been developed for Penicillium paxilli using pAN7-1. Up to 44% of the primary transformants were heterokaryons. Loss of hygromycin resistance was observed in primary transformants that were sub-cultured on non-selective media, but single spores of these primary transformants were mitotically stable on both selective and non-selective media. A molecular analysis of the transformants generated showed that 78% had single-site integrations, with half of these containing a single copy of pAN7-1. CHEF-gel electrophoresis showed that P. paxilli has at least six chromosomes with a total genome size of about 23.4 Mb.  相似文献   
4.
Random amplified polymorphic DNAs (RAPDs) were used as a genetic marker system to characterize recombinant strains following the parasexual cycle of Penicillium roqueforti. After protoplast fusion and haploidization of diploid hybrids, segregants characterized by a reassortment of the parental genetic markers displayed specific RAPD fingerprints. The appearance or the loss of RAPD fragments demonstrate that these markers provide an efficient method to analyze recombination and to characterize somatic hybrids.  相似文献   
5.
竹鼠马尔尼菲青霉菌感染的病理学研究   总被引:1,自引:0,他引:1  
目的 研究马尔尼菲青霉菌感染竹鼠的组织病理学方法。方法 应用HE,Grocotte,免疫组化染色及电镜观察。结果 马尔尼菲青霉菌引起竹鼠各脏器的组织病理学改变为化脓性病变及肉芽肿性病变,病变轻微。结论 竹鼠为马尔尼菲青霉菌的天然储库,主要侵犯竹鼠的肺和单核巨噬细胞系统。  相似文献   
6.
A 19-year-old female on chronic peritoneal dialysis developed acute peritonitis; multiple peritoneal fluid and catheter tip cultures yielded Penicillium species. She promptly responded to catheter removal and intravenous amphotericin B, followed by oral fluconazole, without further recurrences 1 year later. This is the first reported case of Penicillium peritonitis in the pediatric population. We review the microbiology and clinical spectrum of this disease, as well as the few previous reported cases in adults. Received: 2 November 1998 / Revised: 1 February 1999 / Accepted: 4 February 1999  相似文献   
7.
叶黄素酯的生物转化研究   总被引:3,自引:0,他引:3  
陈龙胜  忻旸  周斌 《中草药》2005,36(10):1486-1488
目的对叶黄素酯进行微生物降解,以获得游离态叶黄素。方法采用青霉菌摇瓶发酵转化法,并考察了pH、发酵时间、接种量对转化结果的影响。结果青霉菌在pH值为6.0,接种量为2菌塞,发酵24 h叶黄素酯转化彻底,所得叶黄素纯度为91.6%,延长转化时间使叶黄素纯度增加,但是叶黄素质量浓度降低。结论青霉菌在发酵过程中会产生能转化叶黄素酯为游离态叶黄素的酶,发现制备叶黄素的一种新方法。  相似文献   
8.
目的研究角果木内生真菌Penicillium.sp FJ-1发酵液的化学成分。方法用多种柱色谱技术对该菌发酵液化学成分进行分离纯化,根据波谱数据和理化性质鉴定化合物的结构。结果分离得到5个化合物,经波谱分析鉴定其结构分别为24R-ergosta-7,22-diene-3,5,6-triol(1)、互隔交链孢霉素(2)、5-羟基互隔交链孢霉素(3)、5’-epialtenuene(4)、篮毒菌素黄酮(5)。结论以上5个化合物均为首次从该菌中分离得到,并首次报道了化合物3的核磁数据。  相似文献   
9.
目的提高儿童马内菲青霉菌病的临床诊断水平。方法回顾分析1例原发性免疫缺陷病合并马内菲青霉菌病患儿的临床资料并进行相关文献复习。结果反复发热、"肺炎"、肝脾进行性肿大、皮疹、免疫功能低下等为马内菲青霉菌病的基本特征,骨髓细胞形态学检查见马内菲青霉菌及血液真菌培养发现马内菲青霉菌生长是确诊依据。结论认识马内菲青霉菌病的临床特征,避免漏诊、误诊。  相似文献   
10.
BackgroundPenicillium produces a wide range of structurally diverse metabolites with significant pharmacological impacts in medicine and agriculture. For the first time, a complete metabolome of Penicillium claviforme (P. claviforme) (FBP-DNA-1205) was studied alongside pharmacological research in this study.MethodsThe metabolic profile of P. claviforme fermented on Potato Dextrose Broth (PDB) was investigated in this work. The complete metabolomics studies of fungus were performed using GC-MS and LC-MS-QTOF techniques. An in vitro model was utilised to study the cytotoxic and antioxidant activities, while an in vivo model was employed to investigate the antinociceptive and acute toxicity activities. Molecular Operating Environment (MOE) software was used for molecular docking analysis.ResultsGC-MS study showed the presence of alkanes, fatty acids, esters, azo and alcoholic compounds. Maculosin, obtain, phalluside, quinoline, 4,4’-diaminostilbene, funaltrexamine, amobarbital, and fraxetin were among the secondary metabolites identified using the LC-MS-QTOF technique. The n-hexane fraction of P. claviforme displayed significant cytotoxic activity in vitro, with an LD50 value of 92.22 µgml−1. The antinociceptive effects in vivo were dose-dependent significantly (p < .001). Interestingly, during the 72 h of investigation, no acute toxicity was demonstrated. In addition, a docking study of tentatively identified metabolites against the inflammatory enzyme (COX-2) supported the antinociceptive effect in an in silico model.ConclusionMetabolic profile of P. claviforme shows the presence of biologically relevant compounds in ethyl acetate extract. In addition, P. claviforme exhibits substantial antioxidant and cytotoxic activities in an in vitro model as well as antinociceptive activity in an in vivo model. The antinociceptive action is also supported by a molecular docking study. This research has opened up new possibilities in the disciplines of mycology, agriculture, and pharmaceutics.

Key messages

  • The first time explored complete metabolome through GC-MS and LC-MS-QTOF.
  • Both in vivo & in vitro pharmacological investigation of P. claviforme.
  • In silico molecular docking of LC-MS-QTOF metabolites.
  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号