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131.
E. V. Kulakovskaya T. V. Kulakovskaya V. I. Golubev A. S. Shashkov A. A. Grachev N. E. Nifantiev 《Russian Journal of Bioorganic Chemistry》2007,33(1):156-160
Cellobiose lipids of yeast fungi Cryptococcus huminola and Pseudozyma fusiformata have similar fungicidal activities against different yeast, including pathogenic Cryptococcus and Candida species. Basidiomycetic yeast reveals maximum sensitivity to these preparations; e.g., cells of cryptococcus Filobasidiella neoformans almost completely die after 30-min incubation in a glycolipid solution at a concentration of 0.02 mg/ml. The same effect toward ascomycetous yeast, including pathogenic Candida species, is achieved only at five to eight times higher concentrations of glycolipids. The cellobiose lipid from P. fusiformata, which, unlike glycolipid from Cr. humicola, has hydroxycaproic acid residue as O-subtituent of cellobiose and additional 15-hydroxy group in aglycone, inhibits the growth of the studied mycelial fungi more efficiently than the cellobiose lipid from Cr. humicola. 相似文献
132.
Yoo JY Kim HC Zhu W Kim SM Sabet M Handfield M Hillman J Progulske-Fox A Lee SW 《FEMS microbiology letters》2007,275(2):344-352
Molecular pathogenesis of Tannerella forsythia, a putative periodontal pathogen, has not yet been adequately elucidated due to limited information on its virulence factors. Here, identification of in vivo expressed antigens of T. forsythia is reported using in vivo-induced antigen technology (IVIAT). Among 13 000 recombinant clones screened, 16 positive clones were identified that reacted reproducibly with sera obtained from patients with periodontal disease. DNA sequences from 12 of these in vivo-induced genes were determined. IVIAT-identified protein antigens of T. forsythia include: BspA, a well-defined virulence factor of T. forsythia; enzymes involved in housekeeping functions (tRNA synthetases, glycine hydroxymethyltransferase, and glucoside glucohydrolase); enzymes implicated in tissue destruction (dipeptidyl peptidase IV); a DNA mismatch repair protein; and putative outer membrane proteins of unknown function. The in vivo gene expression of these IVIAT-identified antigens was confirmed by a quantitative real-time PCR analysis. This is, to the best of the authors' knowledge, the first report using IVIAT in T. forsythia. It is anticipated that detailed analysis of the in vivo-induced genes identified by IVIAT in this study will lead to a better understanding of the molecular mechanisms mediating periodontal infection by T. forsythia. 相似文献
133.
Objectives: This trial studied the effects of interventions on the oral cleanliness of the long‐term hospitalised elderly. Background: Oral cleanliness is mostly poor in long‐term facilities. While many agree on the importance of oral hygiene education for nursing personnel, little information and agreement exists on how to organise this education in geriatric institutions. Materials and methods: This is a longitudinal study with interventions. After a baseline clinical examination, the patient wards were divided into three groups (A, B and C) and the type of intervention was randomly assigned. In group A, dental hygienists provided oral hygiene measures for the subjects once every 3 weeks. In group B, the nursing staff first received hands‐on instructions after which they assumed responsibility for the subjects’ daily oral hygiene. Group C served as a control. Denture hygiene and dental hygiene were recorded at baseline and in the end of the 11‐month study period. In total, 130 subjects completed the interventions; their mean age was 82.9 years. Results: The best outcome in both denture and dental hygiene occurred when nursing staff at the wards took care of hygiene (group B). The increase in the proportion of those with good denture hygiene was the most prominent in group B (from 11% to 56%). The proportion of subjects with poor overall dental hygiene decreased from 61% at baseline to 57% in the end, for group B from 80% to 48%. Conclusions: Organised oral health education of the nursing staff should receive more attention. 相似文献
134.
Therapeutic effectiveness of orally administered transgenic low-alkaloid tobacco expressing human interleukin-10 in a mouse model of colitis 总被引:3,自引:0,他引:3
Menassa R Du C Yin ZQ Ma S Poussier P Brandle J Jevnikar AM 《Plant biotechnology journal》2007,5(1):50-59
Inflammatory bowel disease (IBD) represents a spectrum of diseases in which inflammation leads to acute and chronic gut injury. It is a growing health issue for which no cure exists. The pathogenesis is multifactorial with links to infectious and environmental events that trigger disease in genetically predisposed individuals. Treatment of the two major forms of IBD, Crohn's disease and ulcerative colitis, involves the reduction of inflammation with toxic immunosuppressive drugs or blocking of the pro-inflammatory effects of tumour necrosis factor-α (TNF-α) with antibodies. Here, we show that the oral administration of transgenic low-alkaloid tobacco expressing the contra-inflammatory cytokine human interleukin-10 (hIL-10) reduces the severity of colitis by down-regulating TNF-α expression directly at the sites of inflammation in IBD-susceptible IL-10−/– mice. hIL-10 expressed in plants is biologically active and displays resistance to gastrointestinal degradation. Dietary supplementation with plant tissue delivering up to 9 µg of hIL-10 daily for 4 weeks was well tolerated by treated mice. Gut histology was significantly improved relative to controls ( P = 0.002), and was correlated with a decrease in small bowel TNF-α mRNA levels and an increase in IL-2 and IL-1β mRNA levels. Transgenic plants expressing IL-10 to directly attenuate TNF-α expression at sites of inflammation in the gut may become a useful new approach in the luminal therapy of IBD. 相似文献
135.
Saliva diagnostics utilizing nanotechnology and molecular technologies to detect oral squamous cell carcinoma (OSCC) has become an attractive field of study. However, no specific methods have been established. To refine the diagnostic power of saliva peptide fingerprints for the early detection of OSCC, we screened the expression spectrum of salivary peptides in 40 T1 stage OSCC patients (and healthy controls) using MALDI-TOF-MS combined with magnetic beads. Fifty proteins showed significantly different expression levels in the OSCC samples (P<0.05). Potential biomarkers were also predicted. The novel diagnostic proteomic model with m/z peaks of 1285.6 Da and 1432.2 Da are of certain value for early diagnosis of OSCC. 相似文献
136.
Periela da Silva Sousa-Vasconcelos Wellington da Silva Seguins Eduardo de Souza Luz Rosa Teixeira de Pinho 《Memórias do Instituto Oswaldo Cruz》2015,110(6):809-813
Tuberculosis has great public health impact with high rates of mortality and the only
prophylactic measure for it is the Mycobacterium bovisbacillus
Calmette-Guérin (BCG) vaccine. The present study evaluated the release of cytokines
[interleukin (IL)-1, tumour necrosis factor and IL-6] and chemokines [macrophage
inflammatory protein (MIP)-1α and MIP-1β] by THP-1 derived
macrophages infected with BCG vaccine obtained by growing mycobacteria in Viscondessa
de Moraes Institute medium medium (oral) or Sauton medium (intradermic) to compare
the effects of live and heat-killed (HK) mycobacteria. Because BCG has been reported
to lose viability during the lyophilisation process and during storage, we examined
whether exposing BCG to different temperatures also triggers differences in the
expression of some important cytokines and chemokines of the immune response.
Interestingly, we observed that HK mycobacteria stimulated cytokine and chemokine
production in a different pattern from that observed with live mycobacteria. 相似文献
137.
Masaaki Okamoto Susumu Imai Mayu Miyanohara Wataru Saito Yasuko Momoi Yoshiaki Nomura Tomoko Ikawa Takumi Ogawa Takako Miyabe‐Nishiwaki Akihisa Kaneko Akino Watanabe Shohei Watanabe Misato Hayashi Masaki Tomonaga Nobuhiro Hanada 《Microbiology and immunology》2015,59(9):526-532
Three strains TKU9, TKU49 and TKU50T, were isolated from the oral cavities of chimpanzees (Pan troglodytes). The isolates were all gram‐positive, facultative anaerobic cocci that lacked catalase activity. Analysis of partial 16S rRNA gene sequences showed that the most closely related species was Streptococcus infantis (96.7%). The next most closely related species to the isolates were S. rubneri, S. mitis, S. peroris and S. australis (96.6 to 96.4%). Based on the rpoB and gyrB gene sequences, TKU50T was clustered with other member of the mitis group. Enzyme activity and sugar fermentation patterns differentiated this novel bacterium from other members of the mitis group streptococci. The DNA G + C content of strain TKU50T was 46.7 mol%, which is the highest reported value for members of the mitis group (40–46 mol%). On the basis of the phenotypic characterization, partial 16S rRNA gene and sequences data for two housekeeping gene (gyrB and rpoB), we propose a novel taxa, S. panodentis for TKU 50T (type strain = CM 30579T = DSM 29921T), for these newly described isolates. 相似文献
138.
139.
140.
N. Mollaoglu, P. Metzler, J. Zenk, E. Nkenke, F. W. Neukam and J. Ries Prediction of recurrence using exfoliative cytology and melanoma‐associated antigen‐A mRNA analysis following wide excision of oral squamous cell carcinoma: short report Background: Oral squamous cell carcinoma (OSCC) is the sixth most common cancer. The local recurrence of OSSC might result from the existence of occult cancer cells around tumour margins. Exfoliative cytology has lately gained great importance as a method for obtaining RNA samples from suspicious oral mucosal lesions in order to carry out molecular diagnosis. In addition, melanoma associated‐A antigens (MAGE‐A) are expressed in various tumours and their detection is a highly accurate sign that cancer cells are present. Objective: The prediction of a recurrence using MAGE‐A mRNA expression analysis to follow‐up OSCC cases using a newly established molecular diagnostic technique applied to cytological materials. Methods: RNA was extracted from three recurrent OSCC cases and from 20 healthy volunteers as a control group using a cytobrush. The expression of MAGE‐A3, A4, A6, A10 and A12 was investigated in these specimens using quantitative real‐time (RT‐PCR). Results: There was no expression of MAGE‐A in the specimens of normal oral mucosa. However, the expression analysis of five different MAGE‐A genes indicated a high potential for malignant change in biopsy‐proven recurrent OSCC cases. Except for MAGE‐A10, the rest of the genes were expressed in different ratios by the three recurrent cases, which had been determined on histopathology to be OSCC or carcinoma in situ. Conclusion: It is suggested that analysis of MAGE‐A expression may be used as a risk prediction method in the diagnosis of recurrence after wide excision of OSCC to enhance the accuracy of exfoliative cytology, which has limitations due to false negative and false positive results. 相似文献