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991.
992.
993.
We report the case of an 8-year-old child, presenting a rhabdoid tumor of the liver with spontaneous rupture, revealed by an intra-abdominal bleeding with rapidly fatal course. This clinical and pathological report raises the problem of the differential diagnosis of primary malignant hepatic tumors of the child with no alpha-foetoprotein increase.  相似文献   
994.
Many African countries have begun implementation of national programs to eliminate measles by the year 2015. However, measles continues to be endemic in Africa. This study describes the first molecular epidemiological study of measles virus circulating in Central African Republic. Two hundred and ten blood samples were tested for measles IgM. Sixty-seven urine samples were collected during measles outbreak in Bangui in 2000 and 2004 and used for genotyping studies. Two different methods were used to determine measles virus genotypes; the recently described real-time PCR-based method and the nucleotide sequencing and phylogenetic analysis methods. These tests revealed the cocirculation of two distinct viruses in Bangui. The proposed subgroup of the B3 genotype, B3.1 was found in 14 samples. This virus has been found in other neighboring countries. More surprising, genotype B2 was found in samples from four patients. The first measles genotype B2 viruses were isolated in Gabon in 1984, but have not been detected until recently when they were identified during a measles outbreak in 2003 in South Africa. This suggests that the circulation of measles genotype B2 has continued in Central Africa during the last 20 years. This study provides the baseline for genetic surveillance of measles virus in Central African Republic. Knowledge of currently circulating measles virus genotype in Central African Republic will help in monitoring the success of measles elimination program.  相似文献   
995.
Acinetobacter species are defined on the basis of several phenotypic characters, results of DNA-DNA homology, and more recently, similarities or dissimilarities in 16S rRNA gene sequences. However, the 16S rRNA gene is not polymorphic enough to clearly distinguish all Acinetobacter species. We used an RNA polymerase beta-subunit gene (rpoB)-based identification scheme for the delineation of species within the genus Acinetobacter, and towards that end, we determined the complete rpoB gene and flanking spacer (rplL-rpoB and rpoB-rpoC) sequences of the 17 reference strains of Acinetobacter species and 7 unnamed genomospecies. By using complete gene sequences (4,089 bp), we clearly separated all species and grouped them into different clusters. A phylogenetic tree constructed using these sequences was supported by bootstrap values higher than those obtained with 16S rRNA or the gyrB or recA gene. Four pairs of primers enabled us to amplify and sequence two highly polymorphic partial sequences (350 and 450 bp) of the rpoB gene. These and flanking spacers were designed and tested for rapid identification of the 17 reference strains of Acinetobacter species and 7 unnamed genomospecies. Each of these four variable sequences enabled us to delineate most species. Sequences of at least two polymorphic sequences should be used to distinguish Acinetobacter grimontii, Acinetobacter junii, Acinetobacter baylyi, and genomic species 9 from one another. Finally, 21 clinical isolates of Acinetobacter baumannii were tested for intraspecies relationships and assigned correctly to the same species by comparing the partial sequences of the rpoB gene and its flanking spacers.  相似文献   
996.
A fastidious, gram-negative bacterium was isolated from the blood of a 51-year-old man who had acute infectious endocarditis (IE). Characterization of the organism through phenotypic and genotypic analyses revealed the causative role of Cardiobacterium valvarum. This is the third reported case of IE caused by C. valvarum.  相似文献   
997.
We report the first documented case of endocarditis in a man infected with Bartonella alsatica, which causes bacteremia in healthy wild rabbits. B. alsatica was identified by serology and culture and by PCR of an aortic valve specimen. B. alsatica should be added to the list of zoonotic agents of blood culture-negative endocarditis.  相似文献   
998.
Honey bees undergo an age-related, socially regulated transition from working in the hive to foraging that has been previously associated with changes in the expression of thousands of genes in the brain. To understand the meaning of these changes, we conducted microarray analyses to examine the following: (i) the ontogeny of gene expression preceding the onset of foraging, (ii) the effects of physiological and genetic factors that influence this behavioral transition, and (iii) the effects of foraging experience. Although >85% of approximately 5,500 genes showed brain differences, principal component analysis revealed discrete influences of age, behavior, genotype, environment, and experience. Young bees not yet competent to forage showed extensive, age-related expression changes, essentially complete by 8 days of age, coinciding with previously described structural brain changes. Subsequent changes were not age-related but were largely related to effects of juvenile hormone (JH), suggesting that the increase in JH that influences the hive bee-forager transition may cause many of these changes. Other treatments that also influence the onset age of foraging induced many changes but with little overlap, suggesting that multiple pathways affect behavioral maturation. Subspecies differences in onset age of foraging were correlated with differences in JH and JH-target gene expression, suggesting that this endocrine system mediates the genetic differences. We also used this multifactorial approach to identify candidate genes for behavioral maturation. This successful dissection of gene expression indicates that, for social behavior, gene expression in the brain can provide a robust indicator of the interaction between hereditary and environmental information.  相似文献   
999.
African tick bite fever (ATBF) caused by Rickettsia africae is an emerging health problem in travellers to sub-Saharan Africa. We here present 6 patients with evidence of long-lasting sub-acute neuropathy following ATBF contracted during safari trips to southern Africa. Three patients developed radiating pain, paresthaesia and/or motor weakness of extremities, 2 had hemi-facial pain and paresthaesia, and 1 developed unilateral sensorineural hearing loss. When evaluated 3-26 months after symptom onset, cerebrospinal fluid samples from 5 patients were negative for R. africae PCR and serology, but revealed elevated protein content in 3 and mild pleocytosis in 1 case. Despite extensive investigations, no plausible alternative causes of neuropathy could be identified. Treatment with doxycycline in 2 patients had no clinical effect. Given the current increase of international safari tourism to sub-Saharan Africa, more cases of sub-acute neuropathy following ATBF may well be encountered in Europe and elsewhere in the y to come.  相似文献   
1000.
BACKGROUND/AIMS: In France, geographic access to medical care may affect the diagnosis of hepatitis C. The aims of this study were to compare the detection rates of hepatitis C in urban and rural areas after adjusting for distance to medical care, and evaluating the impact of the place of residence on patients' clinical characteristics. METHODS: Between 1994 and 2001, 1938 newly detected cases were recorded in a French population of 1,005,817 inhabitants. Age and sex-adjusted detection rates for 10(5) inhabitants were estimated for urban and rural areas and for classes of distance to the nearest practitioner. RESULTS: Detection rates were lower in rural than in urban areas [14.1, (95CI: 12.5-15.7) versus 24.7, (95CI: 23.5-26.0)] and decreased as the distance to the general practitioner increased [27.0, (95CI: 25.5-28.4) versus 13.7, (95CI: 12.1-15.3) for a cutoff value of 1.5 km]. In multivariate analyses, detection rates were only influenced by the distance to general practitioner. Hepatocellular carcinoma at diagnosis was more frequent among rural than among urban patients (adjusted OR = 2.28, 95CI: 0.97-5.39, P = 0.059). CONCLUSIONS: A poorer geographic access to care explained the lower detection of hepatitis C in rural areas. Hepatocellular carcinoma was more frequent in rural patients. It may result from later detection and/or involvement of environmental factors on hepatocarcinogenesis.  相似文献   
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