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121.
Identification of a novel coronavirus in patients with severe acute respiratory syndrome 总被引:1,自引:0,他引:1
Drosten C Günther S Preiser W van der Werf S Brodt HR Becker S Rabenau H Panning M Kolesnikova L Fouchier RA Berger A Burguière AM Cinatl J Eickmann M Escriou N Grywna K Kramme S Manuguerra JC Müller S Rickerts V Stürmer M Vieth S Klenk HD Osterhaus AD Schmitz H Doerr HW 《The New England journal of medicine》2003,348(20):1967-1976
122.
A direct agglutination test was evaluated for the detection and quantitation of IgG antibodies to Neospora caninum in both experimental and natural infections in various animal species. As compared with results obtained by the indirect
fluorescent antibody test, the direct agglutination test appeared reliable for the serologic diagnosis of neosporosis in a
variety of animal species. The direct agglutination test should provide easily available and inexpensive tools for serologic
testing for antibodies to N. caninum in many host species.
Received: 26 June 1997 / Accepted: 5 August 1997 相似文献
123.
Prof. Dr. R. Knüchel A. Hartmann R. Stöhr R. Baumgartner D. Zaak R. C. Krieg 《Der Pathologe》2003,24(6):473-480
Zusammenfassung In der Fluoreszenzdiagnostik [Lichtanregung nach Gabe des physiologischen Hämmetaboliten 5-Aminolävulinsäure (ALA)] erscheinen Präneoplasien und Neoplasien rot fluoreszierend, was wahrscheinlich auf eine tumorzellselektive Anreicherung des intrazellulär aus ALA gebildeten Metaboliten Protoporphyrin IX zurückzuführen ist. Die mit dieser Methode mögliche frühe Detektion von Tumoren und Präneoplasien erlaubt deren genetische Analyse und damit Vergleiche von Aussagen der Fluoreszenz-in-situ-Hybridisierung und Loss-of-heterozygosity-Analyse hinsichtlich Deletionsnachweis und Gensequenzierung. Neue Daten zu Deletionen und Chromosomenaberrationen sowie eine etwa 30%ige Oligoklonalität von Tumoren werden dargestellt. Die tumorselektive Fluoreszenz scheint biochemisch durch Unterschiede im Hämmetabolismus bedingt zu sein. Durch Gen- und Proteinexpressionsanalysen können evtl. weitere, mit dem Hämmetabolismus assoziierte, tumorspezifische Moleküle identifiziert werden.Die geschilderten Arbeiten erfolgten im Rahmen von Unterstützungen durch die Deutsche Krebshilfe 10-1096-Ha und 70.2200-Ba sowie Industriekooperationen von Medac GmbH und metaGen Pharmaceuticals. 相似文献
124.
Thuillier L Rostane H Droin V Demaugre F Brivet M Kadhom N Prip-Buus C Gobin S Saudubray JM Bonnefont JP 《Human mutation》2003,21(5):493-501
Carnitine palmitoyltransferase 2 (CPT2) deficiency, the most common inherited disease of the mitochondrial long-chain fatty acid (LCFA) oxidation, may result in distinct clinical phenotypes, namely a mild adult muscular form and a severe hepatocardiomuscular disease with an onset in the neonatal period or in infancy. In order to understand the mechanisms underlying the difference in severity between these phenotypes, we analyzed a cohort of 20 CPT2-deficient patients being affected either with the infantile (seven patients) or the adult onset form of the disease (13 patients). Using a combination of direct sequencing and denaturing gradient gel electrophoresis, 13 CPT2 mutations were identified, including five novel ones, namely: 371G>A (R124Q), 437A>C (N146T), 481C>T (R161W), 983A>G (D328G), and 1823G>C (D608H). After updating the spectrum of CPT2 mutations (n=39) and genotypes (n=38) as well as their consequences on CPT2 activity and LCFA oxidation, it appears that both the type and location of CPT2 mutations and one or several additional genetic factors to be identified would modulate the LCFA flux and therefore the severity of the disease. 相似文献
125.
Immunohistochemical characterization of an anti-epithelial monoclonal antibody (mAB lu-5) 总被引:7,自引:0,他引:7
J. von Overbeck C. Stähli F. Gudat H. Carmann C. Lautenschlager U. Dürmüller B. Takacs V. Miggiano Th. Staehelin Ph. U. Heitz 《Virchows Archiv : an international journal of pathology》1985,407(1):1-12
Summary A mouse monoclonal antibody (mAB lu-5) was prepared using a lung cancer cell line as an antigen. The selected clone produces an IgG with a gamma-1 heavy chain and a kappa-light-chain. Immunohistochemical testing of mAB lu-5 on 117 normal tissue biopsies and 474 tumours revealed reactivity with an intracytoplasmic, formaldehyderesistant antigen present in most epithelial and mesothelial cells, but absent in mesenchymal cells. The antibody can therefore be used as a first order, pan-epithelial marker. It proved also useful for fast tumour diagnosis on frozen sections. 相似文献
126.
How to use Chlamydia antibody testing in subfertility patients 总被引:1,自引:9,他引:1
Screening for tubal factor subfertility by means of Chlamydia antibody
testing (CAT) was introduced into the initial work-up of subfertile couples
several years ago. The results reported, however, are heterogeneous, and no
uniformity exists in cut-off levels of titres, or in definitions of tubal
factor subfertility. We performed a prospective cohort study to evaluate
the implications of varying the definitions of tubal pathology and of
modifying the cut-off levels on the clinical impact of CAT in predicting
tubal factor subfertility. In 227 consecutive patients who attended our
fertility clinic, the Chlamydia IgG antibody titre was determined and
related to tuboperitoneal abnormalities at laparoscopy as a reference
standard. According to received operating characteristic (ROC) curve
analysis, a titre of 16 is the optimum cut-off level. Increasing the
cut-off level improves specificity and positive likelihood ratio (LR+), at
the expense of sensitivity and negative LR (LR-). Changing the definition
of tubal factor subfertility from unspecified tuboperitoneal abnormalities
into extensive adhesions and/or bilateral distal tubal occlusion improves
LR+, LR- and kappa significantly. We conclude that CAT is more accurate in
predicting severe distal tubal pathology than unspecified tuboperitoneal
abnormalities. Although from a statistical point of view a titre of 16 is
the optimum cut-off level, from a clinical point of view 32 or 64 may be
preferable, depending on the aim of screening and the inception cohort.
相似文献
127.
Persistence and replication of the human cytomegalovirus genome in lymphoblastoid cells of B and T origin. 总被引:4,自引:0,他引:4
Human lymphoblastoid cells infected in vitro with human cytomegalovirus (CMV) were examined by DNA-DNA reassociation kinetics at various times after virus infection. The results indicate that CMV DNA replicates in two B lymphoblastoid cell lines (Raji and Simpson) and one T-cell line (Molt-4). Multiple copies of the entire CMV genome were found in each cell line. After an initial round of CMV DNA replication, the number of CMV DNA copies per cell gradually decreased with time in Raji and Molt-4 cells. In contrast, Simpson cells maintained a fairly constant number of CMV DNA copies throughout the 15-day experiments. 相似文献
128.
Weber B. H. F. Stöhr H. Siedlaczck I. Longmire J. L. Deaven L. L. Duncan A. M. V. Riess O. 《Chromosome research》1994,2(3):201-207
A cosmid library specific for human chromosome 11 has been constructed from flow-sorted chromosomes. The flow-purified chromosomes were prepared from the hamster/human hybrid line J1 which contains chromosome 11 as the only human chromosome. Individual clones were sampled in 187 microtitre plates, resulting in a total of 17 952 colonies. Hybridization analysis revealed that 83.7% of these clones were of human and 10.4% of hamster origin. The average insert size was estimated at 33.6 kb, and only 2.4% of insert fragments appear to be rearranged. This should result in 494 487 kb of cloned human DNA representing 3.5 chromosome 11 equivalents. We have prepared high-density nylon membranes of the arrayed library containing 1 536 single colonies per filter. We have demonstrated the usefulness of the library in the molecular genetic analysis of human chromosome 11 by testing for the presence of possibly polymorphic simple repeat motifs, by identifying cosmids that contain inserts from the telomeric ends of chromosome 11 and by assessing the potential of the library for rapid chromosome walking. 相似文献
129.
Purification of novel peptide antibiotics from human milk 总被引:5,自引:0,他引:5
Liepke C Zucht HD Forssmann WG Ständker L 《Journal of chromatography. B, Biomedical sciences and applications》2001,752(2):369-377
A strategy was established for the identification of novel antimicrobial peptides from human milk. For the generation of bioactive peptides human milk was acidified and proteolyzed with pepsin simulating the digest in infants stomachs. Separation of proteins and resulting fragments was performed by means of reversed-phase chromatography detecting the antimicrobial activity of each fraction using a sensitive radial diffusion assay. In order to avoid the purification of the known abundant antimicrobial milk protein lysozyme, it was identified in HPLC fractions by its enzymatic activity and by matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS). On condition that lysozyme was not detectable and antibacterial activity of HPLC fractions was caused by a peptide, which was confirmed by proteolytic cleavage leading to a loss of activity, further purification was performed by consecutive chromatographic steps guided by the antibacterial assay. Using this strategy, an as yet unknown casein fragment exhibiting antimicrobial activity was purified in addition to antimicrobial lactoferrin fragments. The new antimicrobial peptide resembles a proteolytic fragment of human casein-K (residues 63-117) and inhibits the growth of gram-positive, gram-negative bacteria, and yeasts. Our results confirm that antimicrobially-active peptides are liberated from human milk proteins during proteolytic hydrolysis and may play an important role in the host defense system of the newborn. 相似文献
130.
Rodgers KE; Girgis W; St Amand K; Campeau J; diZerega GS 《Human reproduction (Oxford, England)》1998,13(9):2443-2451
Adhesion formation is a major source of postoperative morbidity and
mortality. In this study, the ability of a variety of lazaroid formulations
[the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the
non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p.
adhesion formation in three rabbit models was examined. In initial studies,
PNU83836E was administered via Alzet miniosmotic pump to the site of
injury. In the sidewall and double uterine horn models, PNU83,836E was
administered via Alzet miniosmotic pump for the entire postoperative
interval. In the sidewall model, there was a dose- dependent reduction in
the area of the sidewall injury that was involved in adhesions. In the
double uterine horn model, PNU83,836E was administered via Alzet
miniosmotic pump to the area of injury for 1, 2, 3 or 7 days.
Administration for as little as 24 h after surgery significantly reduced
the extent of adhesion formation and the reduction was increased if it was
administered for longer. Further studies were conducted in which various
lazaroid formulations were administered as a bolus at the end of surgery.
In both the sidewall and double uterine horn models, administration of
either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or
lipid emulsion vehicles) at the end of surgery reduced adhesion formation.
Administration of a bolus of PNU74006F 10 min prior to initiation of
surgery with or without additional treatment at the end of surgery further
increased its efficacy in the reduction of adhesion formation.
Administration of a minimum of 1.5 mg before and after surgery (3 mg total)
was required for maximal efficacy. These studies demonstrate that pre- and
postoperative administration of either a steroidal (PNU74006F) or
non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation
and reformation of postoperative adhesions in three animal models.
相似文献