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101.
The Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) defective bacteriophage ST64B has a putative immunity (immC) region consisting of cI, cro and cII-like genes. Since ST64B is widespread in S. Typhimurium, studies were undertaken to determine whether this region might be functional and influence phage typing results. Cloning of ST64B immC-like genes and their subsequent expression in S. Typhimurium DTs showed that this region is able to mediate phage-type conversion in DTs 41 and 44. This confirms the functionality of the immC region and the patterns of lysis produced by phage typing are consistent with the predicted mechanism of action of the encoded protein products. 相似文献
102.
Cost-effectiveness of psychological and pharmacological interventions for generalized anxiety disorder and panic disorder 总被引:3,自引:0,他引:3
Heuzenroeder L Donnelly M Haby MM Mihalopoulos C Rossell R Carter R Andrews G Vos T 《The Australian and New Zealand journal of psychiatry》2004,38(8):602-612
OBJECTIVE: To assess from a health sector perspective the incremental cost-effectiveness of interventions for generalized anxiety disorder (cognitive behavioural therapy [CBT] and serotonin and noradrenaline reuptake inhibitors [SNRIs]) and panic disorder (CBT, selective serotonin reuptake inhibitors [SSRIs] and tricyclic antidepressants [TCAs]). METHOD: The health benefit is measured as a reduction in disability-adjusted life years (DALYs), based on effect size calculations from meta-analyses of randomised controlled trials. An assessment on second stage filter criteria ("equity", "strength of evidence", "feasibility" and "acceptability to stakeholders") is also undertaken to incorporate additional factors that impact on resource allocation decisions. Costs and benefits are calculated for a period of one year for the eligible population (prevalent cases of generalized anxiety disorder/panic disorder identified in the National Survey of Mental Health and Wellbeing, extrapolated to the Australian population in the year 2000 for those aged 18 years and older). Simulation modelling techniques are used to present 95% uncertainty intervals (UI) around the incremental cost-effectiveness ratios (ICERs). RESULTS: Compared to current practice, CBT by a psychologist on a public salary is the most cost-effective intervention for both generalized anxiety disorder (A$6900/DALY saved; 95% UI A$4000 to A$12 000) and panic disorder (A$6800/DALY saved; 95% UI A$2900 to A$15 000). Cognitive behavioural therapy results in a greater total health benefit than the drug interventions for both anxiety disorders, although equity and feasibility concerns for CBT interventions are also greater. CONCLUSIONS: Cognitive behavioural therapy is the most effective and cost-effective intervention for generalized anxiety disorder and panic disorder. However, its implementation would require policy change to enable more widespread access to a sufficient number of trained therapists for the treatment of anxiety disorders. 相似文献
103.
P-31 MR spectroscopy of normal human brain and brain tumors 总被引:2,自引:0,他引:2
Hubesch B; Sappey-Marinier D; Roth K; Meyerhoff DJ; Matson GB; Weiner MW 《Radiology》1990,174(2):401-409
Image-guided phosphorus-31 magnetic resonance (MR)-localized image-selected in vivo spectroscopy was performed on normal human brain and brain tumors. Peak area ratios, absolute molar concentrations of metabolites, and pH were determined. T1 values in normal brain were measured. The most important finding was that the metabolite concentrations detectable with MR spectroscopy in brain tumors were reduced from 20% to 70%. Phosphomonoesters, phosphodiesters, and phosphocreatine (PCr) showed the greatest decreases, while inorganic phosphate (Pi) showed the least change. The PCr-Pi ratio was significantly reduced in tumors. The pH of brain tumors (7.12 +/- 0.03) was more alkaline than that of normal brain (6.99 +/- 0.01). The authors conclude that the metabolite concentrations and pH in human brain tumors differ significantly from those in normal brain. These differences may be ultimately useful in characterizing tumors in man. 相似文献
104.
105.
Comparison of virulence of Legionella longbeachae strains in guinea pigs and U937 macrophage-like cells 下载免费PDF全文
Doyle RM Cianciotto NP Banvi S Manning PA Heuzenroeder MW 《Infection and immunity》2001,69(9):5335-5344
A guinea pig model of experimental legionellosis was established for assessment of virulence of isolates of Legionella longbeachae. The results showed that there were distinct virulence groupings of L. longbeachae serogroup 1 strains based on the severity of disease produced in this model. Statistical analysis of the animal model data suggests that Australian isolates of L. longbeachae may be inherently more virulent than non-Australian strains. Infection studies performed with U937 cells were consistent with the animal model studies and showed that isolates of this species were capable of multiplying within these phagocytic cells. Electron microscopy studies of infected lung tissue were also undertaken to determine the intracellular nature of L. longbeachae serogroup 1 infection. The data showed that phagosomes containing virulent L. longbeachae serogroup 1 appeared bloated, contained cellular debris and had an apparent rim of ribosomes while those containing avirulent L. longbeachae serogroup 1 were compact, clear and smooth. 相似文献
106.
Renate RJ de Groot-Besseling Theo JM Ruers Iris L Lamers-Elemans Cathy N Maass Robert MW de Waal Johan R Westphal 《BMC cancer》2006,6(1):149
Background
Upregulation of endogenous angiostatin levels may constitute a novel anti-angiogenic, and therefore anti-tumor therapy. In vitro, angiostatin generation is a two-step process, starting with the conversion of plasminogen to plasmin by plasminogen activators (PAs). Next, plasmin excises angiostatin from other plasmin molecules, a process requiring a donor of a free sulfhydryl group. In previous studies, it has been demonstrated that administration of PA in combination with the free sulfhydryl donor (FSD) agents captopril or N-acetyl cysteine, resulted in angiostatin generation, and anti-angiogenic and anti-tumour activity in murine models. 相似文献107.
Simonne Cohen Russell Conduit Steven W Lockley Shantha MW Rajaratnam Kim M Cornish 《Journal of Neurodevelopmental Disorders》2014,6(1)
Although there is evidence that significant sleep problems are common in children with autism spectrum disorder (ASD) and that poor sleep exacerbates problematic daytime behavior, such relationships have received very little attention in both research and clinical practice. Treatment guidelines to help manage challenging behaviors in ASD fail to mention sleep at all, or they present a very limited account. Moreover, limited attention is given to children with low-functioning autism, those individuals who often experience the most severe sleep disruption and behavioral problems. This paper describes the nature of sleep difficulties in ASD and highlights the complexities of sleep disruption in individuals with low-functioning autism. It is proposed that profiling ASD children based on the nature of their sleep disruption might help to understand symptom and behavioral profiles (or vice versa) and therefore lead to better-targeted interventions. This paper concludes with a discussion of the limitations of current knowledge and proposes areas that are important for future research. Treating disordered sleep in ASD has great potential to improve daytime behavior and family functioning in this vulnerable population. 相似文献
108.
矽宁对肺泡巨噬细胞功能的影响 总被引:1,自引:0,他引:1
矽宁、梯络龙等药物具有明显降低由Zymosan刺激的大鼠肺泡巨噬细胞的耗氧量,抑制其释放超氧离子、过氧化氢及化学发光量。矽宁具有较强的亲合肺巨噬细胞的能力,并有剂量-效应关系。 相似文献
109.
A 2-month-old, former 28-week premature infant with brochopulmonary dysplasia infected with respiratory syncytial virus was treated with nitric oxide and high frequency oscillatory ventilation after conventional therapy failed. Nitric oxide and high frequency oscillatory ventilation rapidly improved oxygenation allowing recovery without the need for extracorporeal membrane oxygenation. This treatment regimen should be considered as an option in high-risk infants with respiratory syncytial virus infection who meet extracorporeal membrane oxygenation criteria. 相似文献
110.
Fifty-one children with a bacteriologically proven urinary tract infection had both an intravenous urogram (IVU) and a micturating cystogram. The IVU was normal in 35. Only 6 of these children showed reflux in the cystogram, affecting 7 of the 70 ureters at risk. Since reflux on its own does not cause renal damage, which occurs only with super-added infection, detection of reflux is not important providing the urine is kept sterile. We suggest that cystography be deferred providing the IVU is normal until recurrent infections occur while under hospital care, and, with this policy this unpleasant and sometimes hazardous investigation could be avoided in many children with a single urinary tract infection. 相似文献