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81.
Motorcyclists constitute a large proportion of total road casualties in Asian countries Unfortunately, studies conducted for the purpose of evaluating the cost of traffic crashes, and cost-benefit analyses of safety interventions, are almost nonexistent in these countries. The loss-of-output approach to valuing life has been used for many years, yet this method has also long been criticised as it results in significant resource misallocation. This study attempts to overcome this problem by estimating the value of a statistical life among motorcyclists using the willingness-to-pay method that is commonly used in developed countries. The study recommends adopting a value of MYR1.1 million (almost five times the previous estimate) per statistical life for public policy analysis involving motorcycle safety.  相似文献   
82.
83.
Polybrominated diphenyl ethers in Swedish human liver and adipose tissue   总被引:9,自引:0,他引:9  
Paired samples of human liver and adipose tissue were analyzed for polybrominated diphenyl ethers (PBDEs) containing 3–6 bromine atoms. The samples were obtained at autopsy from one woman and four men at the age of 47 and 66–83 years, respectively. PBDEs were found in all samples. The sum of nine PBDE congeners ranged 5–18 ng/g lipids and 4–8 ng/g lipids in liver and adipose tissue, respectively. In three paired samples the concentrations were similar in liver and adipose tissue, while in two of the pairs the concentrations were higher in liver than in adipose tissue. The PBDE congeners 2,2′,4,4′-tetraBDE (BDE-47), 2,2′,4,4′,5-pentaBDE (BDE-99), and 2,2′,4,4′,5,5′-hexaBDE (BDE-153) occurred at highest levels and constituted together 87–96% and 84–94% of the total sum of PBDEs in liver and adipose tissue, respectively. The levels of PBDEs were compared to those of polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), 1,1-bis(4-chlorophenyl)-2,2-dichloroethene (p,p′-DDE), and hexachlorobenzene (HCB). Received: 13 June 2000/Accepted: 1 October 2000  相似文献   
84.
Nine cases of acoustic neurinoma were treated by stereotactic radiosurgery between 1969 and 1974. The follow-up period can now be regarded as sufficiently long for a preliminary evaluation of the results. An arrest of growth or shrinkage of the tumour was observed in 8 of the 9 cases. In one case open surgery was performed 2 years after irradiation and histological examination showed regressive changes of the type expected after irradiation. Audiological examination revealed that in the majority of cases radiosurgery could be performed without causing serious damage to the hearing function. The average hearing loss present before treatment increased on average only 20.0 dB in the most successful 7 cases. None of the patients suffered facial nerve involvement. In small and medium-sized acoustic tumours this method offers a satisfactory therapeutic alternative worthy of consideration.  相似文献   
85.

Background  

Methadone is a synthetic opiate mu receptor agonist that is widely used to substitute for illicit opiates in the management of opiate dependence. It helps prevent opiate users from injecting and sharing needles which are vehicles for the spread of HIV and other blood borne viruses. This study has the objective of determining the utility of daily methadone dose to predict retention rates and re-injecting behaviour among opiate dependents.  相似文献   
86.
2-Oxoglutarate plays a central role as a signal in the regulation of nitrogen metabolism in the phototrophic diazotroph Rhodospirillum rubrum. In order to further study the role of this metabolite, we have constructed an R. rubrum strain that has the capacity to grow on 2-oxoglutarate as sole carbon source, in contrast to wild-type R. rubrum. This strain has the same growth characteristics as wild-type with malate as carbon source, but showed clear metabolic differences when 2-oxoglutarate was used. Among other things, the regulation of nitrogen metabolism is altered, which can be related to different modification profiles of the regulatory PII proteins.  相似文献   
87.
By use of an immunoblotting technique we have investigated the specificity of circulating IgG antibodies with respect to reactions with the alpha-, beta-, gamma- and omega-fractions of gliadin in patients with coeliac disease and in patients with diarrhoea of other causes. Untreated coeliac patients show a characteristic reactivity against polypeptides in the gamma-fraction, with an Mr of 35 and 45 kilodaltons, but only minor reactivity against the other fractions. One coeliac patient exclusively had antibodies to a 80 kilodalton component. Such a reaction pattern was not observed in other groups of patients with diarrhoea, as they had only weak reactions against the gamma-fraction but a stronger reaction against the other fractions. This might indicate that enterocytes of coeliac patients specifically take up distinct polypeptides of gamma-gliadin and by transcellular transport present them to immunocompetent cells. The results also suggest that there are distinct components of gliadin that provoke symptoms in different coeliac patients, indicating a heterogenecity of the disease. The study might lead to new diagnostic methods and to elucidation of the pathogenetic mechanisms behind coeliac disease.  相似文献   
88.
Ribosome and free amino acid content in muscle during hemodialysis   总被引:1,自引:0,他引:1  
Patients (N = 8) with chronic renal failure and uremia treated with hospital hemodialysis were in a pilot study investigated before and after a single hemodialysis session. The extracorporeal dialysis circuit was flushed regularly with saline to avoid clotting and the use of heparin. Percutaneous skeletal muscle biopsies were taken before and after the dialysis to determine the content of free amino acids together with the concentration and size distribution of ribosomes before and after dialysis. After dialysis the alanine concentration in muscle decreased by 20% (P less than 0.05), while all other amino acids were unaffected. The total ribosome concentration per mg of DNA decreased by 31% (P less than 0.01) and the relative proportion of polyribosomes by 7% (P less than 0.05) after the dialysis compared to predialytic values. All individual plasma amino acids decreased during the dialysis procedure except for threonine and arginine, which were unaltered, and leucine and isoleucine, which increased. The decline in ribosome and polyribosome content together with the changes in amino acid levels indicate a low capacity for protein synthesis and increased catabolism in muscle of hemodialyzed patients.  相似文献   
89.
Benzene is classified as carcinogenic compound which is emitted mainly from cars. In this study, benzene was measured at various sites in Nibong Tebal (urban, suburban, town, and rural) of different traffic volume, and traffic counts were performed simultaneously. Monitoring was carried out during the morning and afternoon traffic peaks. The aim of this study is to monitor benzene concentration at several development sites with different traffic flow. The monitoring was done by using indoor air quality meter. The results obtained from monitoring show that the mean concentrations of benzene ranged from 54.7 ppb in the suburban area to 115.1 ppb in the town area. Multiple linear regression analysis correlated the benzene concentrations with traffic volume, temperature, humidity, and time of monitoring as predictors. The results show that R 2 of the model was 0.97 in Taman Cowin site, and it was 0.47 in Taman Nibong Tebal Jaya site. Negative correlation was found between benzene concentration and temperature while there was positive correlation with humidity being found through the study. Pearson’s correlation indicates that gasoline vehicular exhaust could be the major source of benzene. The UK Air Quality Standards stipulated that the annual mean of ambient benzene should not exceed 5 ppb or 16.25 μg/m3. The results show that the current concentrations of benzene exceeded the permissible limits set by the UK standards.  相似文献   
90.
The etiologies of dental fear and dental behavior management problems in children were investigated in a database of information on 2,257 Swedish children 4-6 and 9-11 years old. The analyses were performed using computerized inductive techniques within the field of artificial intelligence. The database held information regarding dental fear levels and behavior management problems, which were defined as outcomes, i.e. dependent variables. The attributes, i.e. independent variables, included data on dental health and dental treatments, information about parental dental fear, general anxiety, socioeconomic variables, etc. The data contained both numerical and discrete variables. The analyses were performed using an inductive analysis program (XpertRule Analyser, Attar Software Ltd, Lancashire, UK) that presents the results in a hierarchic diagram called a knowledge tree. The importance of the different attributes is represented by their position in this diagram. The results show that inductive methods are well suited for analyzing multifactorial and complex relationships in large data sets, and are thus a useful complement to multivariate statistical techniques. The knowledge trees for the two outcomes, dental fear and behavior management problems, were very different from each other, suggesting that the two phenomena are not equivalent. Dental fear was found to be more related to non-dental variables, whereas dental behavior management problems seemed connected to dental variables.  相似文献   
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