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71.
Salmonellosis is become an increasing public health problem in many countries. Serotyping and assessment of antibiotic resistance are useful tools, which assist in understanding the epidemiology of Salmonella infections. In this respect, the Centre of Enterobacteriaceae of Southern Italy provides helpful information on the changing pattern of Salmonella serovars in this geographic area.This paper reports the distribution of serovars and their antibiotic susceptibility in the years 1983–1987. In particular, because of their peculiar trends during this 5-year period, epidemiological features of Mbandaka, Corvallis, Dublin, Infantis and Wien serovars are described.  相似文献   
72.
Facially amphiphilic polymers carrying cationic and hydrophobic groups on the same repeat unit have shown promising antimicrobial activity and biocompatibility, yet they are prone to suffer from protein adhesion which may induce biofilm formation. To overcome this problem, poly(diitaconate)-based copolymers with cationic/hydrophobic and protein-repellent/charge-neutral repeat units are synthesized. The bioactivity profile of surface-attached polymer networks made from these copolymers depends on the ratio of the cationic and charge-neutral repeat units. In all cases, the protein adhesion is substantially reduced compared to purely cationic polymers. At a 50:50 ratio, the polymer coatings are partially protein-repellent and antimicrobial, yet slightly cell toxic. At an intermediate composition of 30:70, they are still antimicrobial and the cell compatibility is substantially improved. The long-term stability of these materials still has to be determined to judge their suitability for medical applications.  相似文献   
73.
Dengue illness can range from mild illness to life-threatening haemorrhage. It is an Aedes-borne infectious disease caused by the dengue virus, which has four serotypes. Each serotype acts as an independent infectious agent. The antibodies against one serotype confer homotypic immunity but temporary protection against heterotypic infection. Dengue has become a growing health concern for up to one third of the world's population. Currently, there is no potent anti-dengue medicine, and treatment for severe dengue relies on intravenous fluid management and pain medications. The burden of dengue dramatically increases despite advances in vector control measures. These factors underscore the need for a vaccine. Various dengue vaccine strategies have been demonstrated, that is, live attenuated vaccine, inactivated vaccine, DNA vaccine, subunit vaccine, and viral-vector vaccines, some of which are at the stage of clinical testing. Unfortunately, the forefront candidate vaccine is less than satisfactory, and its performance depends on serostatus and age factors. The lessons from clinical studies depicted ambiguity concerning the efficacy of dengue vaccine. Our study highlighted that viral structural heterogeneity, epitope accessibility, autoimmune complications, genetic variants, genetic diversities, antigen competition, virulence variation, host-pathogen specific interaction, antibody-dependent enhancement, cross-reactive immunity among Flaviviruses, and host-susceptibility determinants not only influence infection outcomes but also hampered successful vaccine development. This review integrates dengue determinants allocated necessities and challenges, which would provide insight for universal dengue vaccine development.  相似文献   
74.
Background/PurposeNocardiosis is an uncommon infectious disease. This study aimed to assess the clinical outcome of patients with nocardiosis and examine the antimicrobial susceptibility profiles of Nocardia spp. isolated.MethodsWe retrospectively reviewed the medical records of all inpatients diagnosed with nocardiosis between 2011 and 2021. The identification of Nocardia spp. at the species level was performed with the use of MALDI-TOF and 16S rRNA assays. The antimicrobial susceptibility of Nocardia spp. was performed using the microbroth dilution method. Factors associated with 90-day all-cause mortality were identified in multivariate logistic regression analysis.ResultsOf 60 patients with nocardiosis in the 11-year study period, the lungs (55.0%) were the most common site of involvement, followed by the skin and soft tissue (45.0%). Twenty-two patients (36.7%) died within 90 days following the diagnosis. All of the Nocardia isolates were susceptible to trimethoprim-sulfamethoxazole, linezolid, and amikacin, whereas more than 70% of the isolates were not susceptible to ciprofloxacin, imipenem-cilastatin, moxifloxacin, cefepime, and clarithromycin. Nocardiosis involving the lungs (relative risk [RR], 9.99; 95% confidence interval [CI], 1.52–65.50; p = 0.02), nocardiosis involving the skin and soft tissue (RR, 0.15; 95% CI, 0.02–0.92; p = 0.04), and treatment with trimethoprim-sulfamethoxazole (RR, 0.14; 95% CI, 0.03–0.67; p = 0.01) were independently associated with 90-day all-cause mortality.ConclusionsNocardia spp. identified between 2011 and 2021 remained fully susceptible to trimethoprim-sulfamethoxazole, linezolid, and amikacin. Nocardiosis of the lungs, skin and soft tissue infection, and treatment with trimethoprim-sulfamethoxazole were independently associated with 90-day all-cause mortality.  相似文献   
75.
Many Environmental Laws create the unrealistic expectation that science can be used to determine ‘safety'. The many uncertainties surrounding environmental risks, as well as individual, group and societal differences about what is considered ‘safe', make it inevitable that policy decisions must be made. It is appropriate that such decisions be shaped by politics and social issues, as well as be informed by science and economics, but care should be taken to distinguish between policy and fact. Not much is known about the nature and magnitude of environmental susceptibilities. Credible environmental decisions require that scientists, risk assessors and decision-makers acknowledge this, and that they take care to distinguish policy calls from scientific fact.  相似文献   
76.
HBV无症状携带者与ABO血型关系的探讨   总被引:1,自引:0,他引:1  
目的:探讨HBV无症状携带者与ABO血型间关系。方法:采用Woolf统计方法与卡方(x^2)检验方法对174例HBV无症状携带者的ABO血型分布以及男女性别的关系进行系统分析。结果:男性携带者血型呈B〉O〉A〉AB型分布,女性携带者呈B〉A〉O〉AB型分布。A、B、O和AB血型人相对危险率分别是0.4870、2.0414、0.9668和1.7950。结论:HBV无症状携带者与ABO血型间存在一定关  相似文献   
77.
The antimicrobial susceptibility and serogroups of 153 Salmonella strains isolated during a period of 22 months from both children and adults at a major teaching hospital in Riyadh, Saudi Arabia were studied. Antimicrobial susceptibility testing by comparative disc method and MIC determination by E-test method were performed on selected antimicrobial agents. For nalidixic acid and trimethoprim only the comparative disc method was used. Discrepancy between the two methods were noticed only in 1.3% of isolates. The majority of isolates from children (41%) were serogroup B, while those from adults (43%) were serogroup C1. The overall resistance was 16% to ampicillin and ampicillin/sulbactam, 13% to nalidixic acid, and 11% to chloramphenicol and trimethoprim/sulphamethoxazole. The resistance of Salmonella isolates to the so-called first line anti-Salmonella agents, i.e. ampicillin, chloramphenicol and trimethoprim/sulphamethoxazole, has increased compared to that reported 4 years ago from this Institution. Almost all isolates were susceptible to the second, and third generation cephalosporins, fluoroquinolones, aztreonam, mecillinam and gentamicin. Multiple drug resistance to two or more drugs was noticed in 16% of isolates, most of which were serogroup B. The majority of these multiple drug resistant isolates (96%) were ampicillin resistant and β-lactamase producers. Although these isolates showed reduced MICs to ampicillin/sulbactam, their MICs were still higher than the susceptibility breakpoint for this combination. The nalidixic acid-resistant isolates showed higher MICs to the fluoroquinolones compared to the nalidixic acid-sensitive isolates. Isolates from children showed higher resistance to some of the antimicrobial agents compared to those from adults.  相似文献   
78.
围手术期抗菌药物应用的调查分析   总被引:4,自引:0,他引:4  
目的:了解苏州第四人民医院外科手术病人抗菌药物应用的现状及合理性。方法:根据事先设计好的调查表,按统一方法、统一标准和统一内容对10个科室的575例手术病人的出院病历作回顾性调查。结果:外科出院手术病人抗菌药物总使用率92.52%,预防性应用率56.77%。头孢菌素类药物使用频率最高,其次为氟喹诺酮类、硝咪唑类,三共占71.69%。结论:加强抗菌药物应用的管理,执行规范的围手术期抗菌药物的使用原则非常重要。  相似文献   
79.
药敏纸片的质量控制研究   总被引:1,自引:0,他引:1  
目的:探讨和研究药敏纸片质量控制的方法。方法:以克拉霉素药敏纸片为例,参照美国临床实验室标准化委员会(NCCLS)和联邦法规全书(CFR)的方法,建立一套药敏纸片质量控制的指标,包括鉴别、检查及含量测定。结果:采用专属性较强、灵敏度较高的TLC法进行鉴别,最低检出量为50μg;制订纸片的的直径、重量差异、含量均匀性及干燥失重作为检查项,采用短小芽孢杆菌(Bacillus pumilus)[CMCC(B)63202]作为检定菌,进行含量测定。结论:建立的克拉霉素药敏纸片质量标准能够控制其质量,可作为其他抗生素药敏纸片建立质量标准的参考。  相似文献   
80.
阳离子抗菌肽研究进展   总被引:8,自引:0,他引:8  
阳离子抗菌肽广泛分布于多种生物 ,越来越多的证据表明它们在机体天然免疫中有着重要的作用。广谱抗菌、抗病毒、抗肿瘤细胞及其它特性也使得其具有潜在的医药价值。对抗菌肽的研究正不断深入。该文从一般性质、作用机制、构效关系、重组表达、应用价值、存在的问题与发展方向等方面 ,对阳离子抗菌肽的最新研究进展进行综述  相似文献   
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