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排序方式: 共有7150条查询结果,搜索用时 15 毫秒
61.
Molecular detection of Histoplasma capsulatum var. capsulatum in human clinical samples 总被引:2,自引:0,他引:2
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Bracca A Tosello ME Girardini JE Amigot SL Gomez C Serra E 《Journal of clinical microbiology》2003,41(4):1753-1755
We developed a seminested PCR for the diagnosis of histoplasmosis that amplifies a portion of the Histoplasma capsulatum H antigen gene. This assay is highly sensitive and specific, being able to detect genomic material corresponding to less than 10 yeast cells without cross-reaction against other bacterial or fungal pathogens. 相似文献
62.
Sharma R Bhatti S Gomez M Clark RM Murray C Ashizawa T Bidichandani SI 《Human molecular genetics》2002,11(18):2175-2187
Friedreich ataxia is commonly caused by large expansions of a GAA triplet-repeat (GAA-TR) sequence in the first intron of the FRDA gene. We used small-pool PCR to analyze somatic variability among 7190 individual FRDA molecules from peripheral blood DNA of subjects carrying 12 different expanded alleles, ranging in size from 241 to 1105 triplets. Expanded alleles showed a length-dependent increase in somatic variability, with mutation loads ranging from 47% to 78%. We noted a strong contraction bias among long alleles (>500 triplets), which showed a 4-fold higher frequency of large contractions versus expansions. Some contractions were very large; of all somatic mutations scored, approximately 5% involved contractions of >50% of the original allele length, and 0.29% involved complete reversion to the normal/premutation length (< or =60 triplets). These observations contrast sharply with the strong expansion bias seen in expanded CTG triplet repeats in myotonic dystrophy. No somatic variability was detected in >6000 individual FRDA molecules analyzed from 15 normal alleles (8-25 triplets). A premutation allele with 44 uninterrupted GAA repeats was found to be unstable, ranging in size from 6 to 113 triplets, thus establishing the threshold for somatic instability between 26 and 44 GAA triplets. Analysis of an additional 7850 FRDA molecules from serially passaged lymphoblastoid cell lines carrying nine expanded alleles (132-933 triplets) showed very low mutation loads, ranging from 0% to 6.2%. Our data indicate that expanded GAA-TR alleles in Friedreich ataxia are highly mutable and have a natural tendency to contract in vivo, and that these properties depend on multiple factors, including DNA sequence, triplet-repeat length and unknown cell-type-specific factors. 相似文献
63.
Giulia Barcia Marlne Rio Zahra Assouline Coralie Zangarelli Charles-Joris Roux Pascale de Lonlay Julie Steffann Isabelle Desguerre Arnold Munnich Jean-Paul Bonnefont Nathalie Boddaert Agns Rtig Metodi D. Metodiev Benedetta Ruzzenente 《European journal of human genetics : EJHG》2021,29(3):533
Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Hypomorphic and loss-of-function variants in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Compound heterozygous or homozygous missense and frameshift variants in the FARS2 gene, that encodes the mitochondrial phenylalanyl-tRNA synthetase, are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.Subject terms: Metabolic disorders, Mutation 相似文献
64.
Cryptosporidium parvum-specific CD4 Th1 cells from sensitized donors responding to both fractionated and recombinant antigenic proteins 总被引:1,自引:0,他引:1
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Gomez Morales MA Mele R Ludovisi A Bruschi F Tosini F Riganò R Pozio E 《Infection and immunity》2004,72(3):1306-1310
T-cell-mediated immunity plays a central role in the host response to Cryptosporidium parvum. Human T-cell clones (TCC) were isolated from peripheral blood mononuclear cells of five healthy donors with prior cryptosporidiosis by use of a C. parvum crude extract, two antigen fractions obtained by ion-exchange chromatography (IEC1 and IEC2), and two recombinant peptides (SA35 and SA40) from C. parvum sporozoites. The T-cell lines derived from the one recently infected donor had a higher proportion (26 to 38%) of T cells exhibiting the gamma/delta T-cell receptor (gamma/delta-TCR) than those from donors who had recovered from cryptosporidiosis several years earlier, suggesting that the gamma/delta T-cell population is involved in the early stage of the infection. The specific TCC had the alpha/beta-TCR, had the phenotype CD45RO(+) CD4(+) CD8(-), and were characterized by either hyperproduction of gamma interferon (IFN-gamma) alone, with a Th1 profile, or IFN-gamma hyperproduction together with interleukin-4 (IL-4) or IL-5 production, with a Th0 profile. SA35, SA40, IEC1, and IEC2 may be considered good targets of the cellular response against C. parvum and may play a role in maintaining the T-cell-mediated memory response to this parasite. Furthermore, the SA35 and SA40 peptides may be regarded as immunodominant antigens involved in the maintenance of the T-cell response in healthy C. parvum-sensitized persons. 相似文献
65.
66.
Baujat G Rio M Rossignol S Sanlaville D Lyonnet S Le Merrer M Munnich A Gicquel C Colleaux L Cormier-Daire V 《American journal of medical genetics. Part C, Seminars in medical genetics》2005,(1):4-11
Here, we report the clinical and molecular analysis of 75 patients with overgrowth and mental retardation, including 45 previously reported cases [Rio et al., 2003; Baujat et al., 2004]. Two groups are distinguished: group I corresponding to patients with recognizable overgrowth syndromes (Sotos syndrome (SS), Weaver syndrome (WS), Beckwith-Wiedemann syndrome, Simpson-Golabi-Behmel syndrome (SGBS), and del(22)(qter) syndrome) (60 cases) and group II corresponding to unclassified cases (15 patients). We investigated NSD1 and GPC3 deletions or mutations, 11p15 abnormalities, and 22qter deletions. Surprisingly, in Group I, two SS patients had 11p15 abnormalities and two patients with Beckwith-Wiedemann syndrome had NSD1 aberrations. In group II, two cases of del(22)(qter) were identified but neither NSD1, 11p15, nor GPC3 abnormalities were detected. These results emphasize the clinical and molecular overlap in overgrowth conditions. 相似文献
67.
Loubinoux J Rio B Mihaila L Foïs E Le Fleche A Grimont PA Marie JP Bouvet A 《Journal of clinical microbiology》2005,43(7):3564-3566
A yellow-pigmented rod- to coccoid-shaped coryneform microorganism was isolated from the blood of a patient with acute myeloid leukemia. It was identified by 16S rRNA gene sequencing as a previously undescribed species of Janibacter. The isolate was susceptible to penicillins, aminoglycosides, fluoroquinolones, and glycopeptides. 相似文献
68.
Nielsen M Franken PF Reinards TH Weiss MM Wagner A van der Klift H Kloosterman S Houwing-Duistermaat JJ Aalfs CM Ausems MG Bröcker-Vriends AH Gomez Garcia EB Hoogerbrugge N Menko FH Sijmons RH Verhoef S Kuipers EJ Morreau H Breuning MH Tops CM Wijnen JT Vasen HF Fodde R Hes FJ 《Journal of medical genetics》2005,42(9):e54
Objective: To investigate the contribution of MYH associated polyposis coli (MAP) among polyposis families in the Netherlands, and the prevalence of colonic and extracolonic manifestations in MAP patients. Methods: 170 patients with polyposis coli, who previously tested negative for APC mutations, were screened by denaturing gradient gel electrophoresis and direct sequencing to identify MYH germline mutations. Results: Homozygous and compound heterozygous MYH mutations were identified in 40 patients (24%). No difference was found in the percentage of biallelic mutation carriers between patients with 10–99 polyps or 100–1000 polyps (29% in both groups). Colorectal cancer was found in 26 of the 40 patients with MAP (65%) within the age range 21 to 67 years (median 45). Complete endoscopic reports were available for 16 MAP patients and revealed five cases with gastro-duodenal polyps (31%), one of whom also presented with a duodenal carcinoma. Breast cancer occurred in 18% of female MAP patients, significantly more than expected from national statistics (standardised morbidity ratio = 3.75). Conclusions: Polyp numbers in MAP patients were equally associated with the attenuated and classical polyposis coli phenotypes. Two thirds of the MAP patients had colorectal cancer, 95% of whom were older than 35 years, and one third of a subset of patients had upper gastrointestinal lesions. Endoscopic screening of the whole intestine should be carried out every two years for all MAP patients, starting from age 25–30 years. The frequent occurrence of additional extraintestinal manifestations, such as breast cancer among female MAP patients, should be thoroughly investigated. 相似文献
69.
Intestinal immune response of volunteers ingesting a strain of enteroadherent (HEp-2 cell-adherent) Escherichia coli. 总被引:1,自引:0,他引:1
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H F Gomez J J Mathewson P C Johnson H L DuPont 《Clinical and Vaccine Immunology : CVI》1995,2(1):10-13
Enteroadherent Escherichia coli (EAEC) strains identified by adherence to HEp-2 tissue culture cells have been incriminated epidemiologically as important etiologic agents of diarrheal disease in both adult travelers and children in developing countries. One strain, JM 221, with no recognized E. coli virulence characteristics other than adherence to HEp-2 cells, caused diarrhea in 5 of 16 volunteers ingesting it. We studied the secretory immunoglobulin A (sIgA) responses to EAEC JM 221 of five volunteers with diarrhea and five volunteers who remained healthy after challenge. sIgA was extracted from stools obtained prechallenge and 7 days postchallenge. Total sIgA was standardized for all specimens. Specific sIgA titers were determined by dot blotting with the following JM 221 antigens: water-extractable surface antigens, whole cells, lipopolysaccharides, and outer membrane proteins. All five subjects who became ill had fourfold or greater rises in titers against each of the four antigens. The five subjects who remained healthy following challenge did not exhibit significant rises in titers to any JM 221 antigens, but their mean titers were significantly higher than the mean prechallenge titers of the volunteers with diarrhea, suggesting that high intestinal sIgA titers may be protective. The significant increases in intestinal antibody against JM 221 in the subjects who became ill is further evidence of the enteropathogenicity of EAEC strains. 相似文献
70.
Adrenergic mechanisms in cerebral circulation of the goat 总被引:1,自引:0,他引:1