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61.
PCR amplification and comparison of nucleotide sequences from the groESL heat shock operon of Ehrlichia species. 总被引:2,自引:1,他引:2
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Degenerate PCR primers derived from conserved regions of the eubacterial groESL heat shock operon were used to amplify groESL sequences of Ehrlichia equi, Ehrlichia phagocytophila, the agent of human granulocytic ehrlichiosis (HGE), Ehrlichia canis, Bartonella henselae, and Rickettsia rickettsii. The groESL nucleotide sequences were less conserved than the previously determined 16S rRNA gene sequences of these bacteria. A phylogenetic tree derived from deduced GroEL amino acid sequences was similar to trees based on 16S rRNA gene sequences. Nucleotide sequences obtained from clinical samples containing E. equi, E. phagocytophila, or the HGE agent were very similar (99.9 to 99.0% identity), and the deduced amino acid sequences were identical. Some divergence was evident between nucleotide sequences amplified from samples originating from the United States (E. equi and the HGE agent) and sequences from the European species, E. phagocytophila. A single pair of PCR primers derived from these sequences was used to detect E. chaffeensis and HGE agent DNA in blood samples from human patients with ehrlichiosis. 相似文献
62.
Campylobacter butzleri sp. nov. isolated from humans and animals with diarrheal illness. 总被引:6,自引:3,他引:6
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J A Kiehlbauch D J Brenner M A Nicholson C N Baker C M Patton A G Steigerwalt I K Wachsmuth 《Journal of clinical microbiology》1991,29(2):376-385
Seventy-eight aerotolerant Campylobacter isolates were characterized phenotypically and by DNA hybridization (hydroxyapatite method at 50 and 65 degrees C). Two DNA relatedness groups were found. (i) Sixty-four strains belonged to aerotolerant Campylobacter DNA hybridization group 2. These organisms were isolated from humans, primarily with diarrheal illness, and animals on several continents. Strains were aerotolerant at 30 and 36 degrees C and catalase negative or weakly catalase positive, grew in media containing glycine and on MacConkey agar, were susceptible to nalidixic acid, and were resistant to cephalothin. The name Campylobacter butzleri sp. nov. is proposed for this group. (ii) DNA hybridization group 1 consisted of the type strain of Campylobacter cryaerophila and 13 additional strains isolated from 10 animals outside the United States and from three humans within the United States. This group was genetically diverse; five strains were closely related to the type strain of C. cryaerophila (DNA hybridization group 1A), and eight strains were more closely related to one another (DNA hybridization group 1B). Strains in DNA hybridization group 1B were phenotypically diverse, with two of eight strains resembling C. cryaerophila. The seven strains from DNA hybridization groups 1A and 1B which resembled C. cryaerophila and the C. cryaerophila type strain were aerotolerant only at 30 degrees C and catalase positive, did not grow in glycine or on MacConkey agar, were generally susceptible to nalidixic acid, and were resistant to cephalothin. The remaining six strains of DNA hybridization group 1B phenotypically resembled C. butzleri; however, they were generally catalase positive and susceptible to nalidixic acid and cephalothin. DNA hybridization group 1B is not designated as a separate species at this time since it cannot, with certainty, be separated genetically from C. cryaerophila or phenotypically from C. butzleri. 相似文献
63.
CD2 and other surface molecules in the regulation of non-MHC-restricted cytolytic function.
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The effect of anti-CD2 and Fc receptor binding molecules on the cytolytic function of a highly enriched population of CD3- large granular lymphocytes (LGL) was studied. These cells could mediate natural killer (NK) activity, antibody-dependent cellular cytotoxicity (ADCC) and lectin-dependent cellular cytotoxicity (LDCC). Both ADCC and LDCC were enhanced by anti-CD2. The enhanced LDCC could also be observed with IL-2-activated LGL. However, NK cell activity was usually slightly diminished or unaffected by anti-CD2 binding. Immune complex and aggregated human IgG had no effect on ADCC but an anti-CD16 showed a dose-dependent inhibition of ADCC, reversible by anti-HLA-ABC and anti-CD2. Cross-linking of LGL surface-bound anti-CD2 caused an almost complete inhibition of LDCC and ADCC but had much less effect on NK activity. These experiments show that ADCC and LDCC mediated by CD3- LGL can be influenced by perturbing the CD2 molecule. NK activity was, however, affected differently, suggesting some basic differences in the pathway of ADCC and NK function. 相似文献
64.
Quantitative Analysis of Mycobacterial and Propionibacterial DNA in Lymph Nodes of Japanese and European Patients with Sarcoidosis 总被引:10,自引:0,他引:10
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Yoshinobu Eishi Moritaka Suga Ikuo Ishige Daisuke Kobayashi Tetsuo Yamada Tamiko Takemura Touichiro Takizawa Morio Koike Shoji Kudoh Ulrich Costabel Josune Guzman Gianfranco Rizzato Marcello Gambacorta Ronald du Bois Andrew G. Nicholson Om P. Sharma Masayuki Ando 《Journal of clinical microbiology》2002,40(1):198-204
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis. 相似文献
65.
66.
Assessment of fetal-maternal haemorrhage in mothers with hereditary persistence of fetal haemoglobin.
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W N Patton G S Nicholson A H Sawers I M Franklin F A Ala A W Simpson 《Journal of clinical pathology》1990,43(9):728-731
Kleihauer examination of peripheral blood cannot be used reliably to detect transplacental fetal-maternal haemorrhage in mothers with hereditary persistence of fetal haemoglobin (HPFH). In Rh(D) negative pregnancies diagnostic confusion with a large fetal-maternal haemorrhage could result in the administration of inappropriately excessive amounts of anti-D immunoglobulin, and the inability to diagnose and quantify transplacental haemorrhage in maternal HPFH by current methods could result in insufficient anti-D administration and subsequent Rh(D) sensitisation. Accordingly, a method to detect and quantify fetal-Rh(D) positive maternal haemorrhage using erythrocyte fluorescent immunocytometry was developed. An indirect immunofluorescence method with IgG anti-D immunoglobulin as the primary antibody was used, combined with quantitative analysis on a fluorescence activated cell sorter. The method was accurate, specific, and sensitive and could detect a contaminating population of 0.1% Rh(D) positive cells in Rh(D) negative blood--a level of fetal-maternal haemorrhage well covered by a single dose of 500 IU of anti-D immunoglobulin. 相似文献
67.
Perry JD Butterworth LA Nicholson A Appleby MR Orr KE 《Journal of clinical pathology》2003,56(7):528-531
AIMS: To compare the performance of a new chromogenic medium, Uriselect 4, with cystine lactose electrolyte deficient (CLED) agar and an established chromogenic agar, CPS ID 2 medium, for detection of urinary tract pathogens. METHODS: Using a semiquantitative culture method, 777 samples were inoculated on to the three test media in duplicate. All bacterial strains that yielded a potentially significant growth were observed for colony colour and identified using standard methods. RESULTS: Of the 777 samples tested, 589 urine samples yielded potentially significant growth of at least one strain. A total of 811 strains were isolated on at least one of the three media. A total of 168 urine samples yielded a mixture of at least two strains. Uriselect 4 medium showed the best sensitivity of the three media and only failed to recover 14 strains (1.7%). CPS ID 2 medium failed to recover 22 strains (2.7%). CLED medium showed the worst recovery and failed to recover 74 strains (9.1%). Both chromogenic media allowed for identification of Escherichia coli with a high degree of specificity (98% for Uriselect 4, 99.7% for CPS ID 2). Inclusion of a spot indole test increased the specificity of both chromogenic media to 100% for E coli. CONCLUSIONS: Uriselect 4 and CPS ID 2 were superior to CLED medium for the isolation of urinary tract pathogens mainly because of their ability to discriminate mixed cultures. Both chromogenic media were also useful for the preliminary identification of the most common urinary tract pathogens. 相似文献
68.
Immunoblot analysis of immunoglobulin G response to the Lyme disease agent (Borrelia burgdorferi) in experimentally and naturally exposed dogs. 总被引:10,自引:8,他引:10
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R T Greene R L Walker W L Nicholson H W Heidner J F Levine E C Burgess M Wyand E B Breitschwerdt H A Berkhoff 《Journal of clinical microbiology》1988,26(4):648-653
Immunoblots were used to study the immunoglobulin G response to Borrelia burgdorferi in experimentally and naturally exposed dogs. Adsorption studies confirmed that the antibodies were specific for B. burgdorferi. Experimentally exposed dogs were asymptomatic. Naturally exposed dogs included both asymptomatic animals and animals showing signs compatible with Lyme disease. Naturally exposed dogs were from four geographic regions of the country. No differences were detected between immunoblot patterns of naturally exposed symptomatic or asymptomatic dogs from different areas of the country. The immunoblot patterns obtained with sera from experimentally exposed dogs were different from those obtained with sera from naturally exposed dogs and were characterized by reactivity to fewer and different protein bands. Immunoblot analysis using an OspA-protein-producing Escherichia coli recombinant showed that experimentally exposed dogs produced antibodies to OspA, whereas naturally exposed dogs did not. Modifications of the immune response over time, different routes of antigen presentation, and strain variation are factors postulated to account for the observed differences. 相似文献
69.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
70.
doublecortin is the major gene causing X-linked subcortical laminar heterotopia (SCLH) 总被引:12,自引:0,他引:12
des Portes V; Francis F; Pinard JM; Desguerre I; Moutard ML; Snoeck I; Meiners LC; Capron F; Cusmai R; Ricci S; Motte J; Echenne B; Ponsot G; Dulac O; Chelly J; Beldjord C 《Human molecular genetics》1998,7(7):1063-1070
Subcortical laminar heterotopia (SCLH), or 'double cortex', is a cortical
dysgenesis disorder associated with a defect in neuronal migration.
Clinical manifestations are epilepsy and mental retardation. This disorder,
which mainly affects females, can be inherited in a single pedigree with
lissencephaly, a more severe disease which affects the male individuals.
This clinical entity has been described as X- SCLH/LIS syndrome. Recently
we have demonstrated that the doublecortin gene, which is localized on the
X chromosome, is implicated in this disorder. We have now performed a
systematic mutation analysis of doublecortin in 11 unrelated females with
SCLH (one familial and 10 sporadic cases) and have identified mutations in
10/11 cases. The sequence differences include nonsense, splice site and
missense mutations and these were found throughout the gene. These results
provide strong evidence that loss of function of doublecortin is the major
cause of SCLH. The absence of phenotype-genotype correlations suggests that
X-inactivation patterns of neuronal precursor cells are likely to
contribute to the variable clinical severity of this disorder in females.
相似文献