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71.

Background  

Human multipotent stromal (skeletal, mesenchymal) stem cells (hMSC) are employed in an increasing number of clinical trials for tissue regeneration of age-related degenerative diseases. However, routine use of fetal bovine sera (FBS) for their in vitro expansion is not optimal and may pose a health risk for patients.  相似文献   
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This report describes the utility of antigens prepared from different coccoid and spiral forms of Helicobacter pylori in a serological method. The presence of IgM antibody to H. pylori was determined in 22 human sera on antigens prepared from 24 strains of H. pylori. Antigens prepared from spiral form of certain strains of H. pylori detected IgM in all confirmed positive sera. Antigens obtained from the coccoid cells of the same strains could not completely detect IgM in the same sera. Testing sera on boosted antigens of the coccoid cells showed reduction in the number of false negative, indicating that the coccoid cells do not have one or more antigenic fractions essential for accurate detection of antibody. Our data suggest that H. pylori may lose CagA during the coccoid conversion process and regain it in the spiral form. In conclusion, we suggest that the antigen used for the detection of antibodies to H. pylori in serological methods should contain a broad spectrum of antigenic fractions and should be prepared from certain strains and culturable cells of H. pylori.  相似文献   
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AIM:To assess hepatitis C virus(HCV)genotype patterns among high-risk Iranian groups,using real-time RT-PCR.METHODS:In this study,we evaluated the distribution of different HCV genotypes among injection drug users and other high-risk groups over a 4-year period(from 2009 to 2012)using real-time polymerase chain reaction(PCR).Sera from 888 HCV-infected patients residing in southern and southwest Iran were genotyped using real-time PCR with common primers and specific probes.These patients were grouped into distinct exposure categories.Illicit drug users constituted the primary group and were further evaluated for HCV genotype distribution and parameters such as age range.RESULTS:Of the examined HCV-infected patients,62%were substance abusers,although the route of transmission could not be determined in approximately 30%of these patients.HCV genotyping revealed that Gt1 was the most prevalent genotype among the drug users as well as among patients with thalassemia,hemophilia,solid organ recipients and those on hemodialysis.Mixed infections were only seen in addict groups,where Gt2 genotype was also found.The highest frequencies in HCV-positive addict patients were observed in the 31-40 age group.Our research also showed that the addiction age has increased,whereas the addiction rate has dropped in this region.Most illicit drug users had more than one risk factor such as tattoo and/or a history of imprisonment.CONCLUSION:This study revealed that the most common HCV-infection route and HCV-genotype in southern and southwest Iran was illicit drug abuse and Gt1,respectively.  相似文献   
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目的 应用一种小型分光光度计对上前牙区种植支持式氧化锆全瓷修复与贵金属金瓷修复的牙冠颜色进行比较,为临床选择修复材料提供参考依据。方法 纳入 18例(男 7例,女 11例)行口腔种植修复后复查患者的上前牙区种植支持式单冠 29颗进行研究,其中氧化锆全瓷修复单冠 11颗,贵金属金瓷修复单冠 18颗。采用小型反射型分光光度计型比色仪 SpectroShadeTM采集图片并输入计算机,应用相关软件测量每个种植牙冠体 1/3与对照天然牙的CIE L﹡a﹡b﹡颜色差异。应用统计学软件 SPSS 17.0进行统计分析。结果 氧化锆全瓷修复和贵金属金瓷修复的牙冠明度均高于天然牙,全瓷修复引起的明度差异( 4.5±3.2)大于金瓷修复引起的明度差异( 1.0±2.6),具有统计学意义( P=0.004);色相差异和饱和度差异均无统计学意义。全瓷修复和金瓷修复与天然牙的颜色差异( 7.0±2.8和4.0±1.9)均高于人眼的分辨阈值( 3.7),且前者差异大于后者,具有统计学意义( P=0.002)。氧化锆全瓷和贵金属金瓷两种修复方式的临床主观评分无统计学差异( P=0.977)。上前牙天然牙色由前向后明度渐低,色相变红黄。结论 就本试验所选用的修复材料而言,分光光度计测量显示氧化锆全瓷修复与天然牙的牙冠颜色差异大于贵金属金瓷修复与天然牙的颜色差异,但两种修复方式的临床效果无明显区别。  相似文献   
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Mupirocin is a topical antibiotic for methicillin-resistant Staphylococcus aureus (MRSA) decolonization in hospital settings and nursing homes and is used as a highly effective antibiotic against MRSA. In this study, we aimed to evaluate the frequency of high-level mupirocin-resistant (HLMR) strains among the MRSA subtypes. A total of 188 clinical MRSA isolates were collected from 2011 to 2014, and their susceptibility to antimicrobial agents and vancomycin resistance was evaluated using disc diffusion method and micro-dilution method, respectively. Furthermore, the presence of mecA, SSCmec, mupA and mupB was assessed by PCR. All isolates were multi-drug resistant (MDR) but 2 strains (1.06%) were resistant to mupirocin. Minimum inhibitory concentration (MIC) of vancomycin for 8 strains (4.7%) was higher than 2 μg/ml. Of 188 isolates, 188 (100%), 64 (34.04%), 8 (4.3%), 150 (79.8%), 26 (13.8%), 2 (1.06) and 2 (1.06%) isolates possessed mecA, SCCmec types I, II, III, IV, mupA and mupB genes, respectively. Our data showed that despite infection control policy enforced by health care committee, the rate of mupirocin resistance among MRSA strains is continuously rising.  相似文献   
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Helicobacter pylori-associated infections are extremely common in Iran, but few data about antibiotic sensitivity of H. pylori are available for this region. The purpose of this study was to investigate the prevalence of resistance in isolates against commonly used antibiotics in Eastern Azerbaijan, Iran, and the dependence of prevalence on the sex and age of patients. H. pylori isolates were collected by culture from gastric biopsies. Antibiotic susceptibility of isolates was determined by use of the disk agar diffusion test, and the minimum inhibitory concentration of clarithromycin was established by use of the Etest. A total 395 of biopsy specimens were studied; 112 samples of H. pylori were isolated (28.3 %), 55 (49 %) from males and 57 (51 %) from females. The prevalence of resistance to clarithromycin, metronidazole, erythromycin, amoxicillin, ciprofloxacin, rifampin, nitrofurantoin, and tetracycline were 16 (14.3 %), 86 (76.8 %), 29 (26.0 %), 32 (28.6 %), 37 (33.0 %), 32 (28.6 %), 13 (11.6 %), and 21 (18.7 %), respectively. Antimicrobial resistance was not statistically significantly associated with sex or age. Furthermore, the prevalence of resistance to metronidazole was high and that to clarithromycin was reasonable, consistent with reported low success in H. pylori treatment in this area. Therefore, continuous surveillance of antibiotic resistance of H. pylori is essential.  相似文献   
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