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991.
Malignant lymphoma induced by partially purifiedHerpesvirus saimiri and recovery of infectious virus from tumorous lymph nodes 总被引:3,自引:0,他引:3
Summary Supernatant of OMK cells infected withHerpesvirus saimiri (HVS) and partially purified HVS were shown to induce malignant lymphoma in New World monkeys (Saguinus oedipus). Radioactively labeled HVS was partially purified by velocity sedimentation in sucrose and buoyant density centrifugation in potassium tartrate and inoculated in a monkey. Infectious HVS was isolated from a tumorous lymph node of this animal 2 h after its cultivationin vitro. In contrast to the lymphocytes from fresh peripheral blood cocultivation of the cells obtained from the lymph node was not necessary for the isolation of the virus. The development of comparatively high amounts of neutralizing antibodies against HVS in the sera of the fatally diseased monkeys is an indication for a replication of HVS in the tumor bearing animals.
Zusammenfassung Der Gewebekulturüberstand von mitHerpesvirus saimiri (HVS) infizierten OMK-Zellen und partiell gereinigtes HVS induzierten in Marmoset Affen (Saguinus oedipus) die Entwicklung von malignen Lymphomen. Radioaktiv markiertes HVS wurde durch Sedimentation im Saccharosegradienten und anschließende Dichtezentrifugation im Kaliumtartratgradienten partiell gereinigt und in einen Affen inoculiert. Bei diesem Tier konnte infektiöses HVS von einem tumorösen Lymphknoten 2 Std nach dessen Kultivationin vitro isoliert werden. Im Gegensatz zu den Lymphocyten aus frischem peripheren Blut war eine Kokultivation der Zellen aus dem Lymphknoten für die Isolierung des Virus nicht erforderlich. Die Entwicklung vergleichsweise hoher Titer neutralisierender Antikörper in den Seren der an einem Tumor erkrankten Tiere kann als Hinweis dafür gewertet werden, daß sich das HVS in diesen Affenin vivo vermehrt.相似文献
992.
Theegarten D Mogilevski G Anhenn O Stamatis G Jaeschock R Morgenroth K 《Virchows Archiv : an international journal of pathology》2000,437(2):190-193
Chlamydia pneumoniae has been detected in atherosclerotic plaques by various means. Chlamydiae are able to cause persistent infections. Serologically
elevated antibody titers are found in severe chronic obstructive pulmonary disease. In atherosclerosis and pulmonary emphysema,
inflammatory reactions can be seen by means of light microscopy. Specimens from patients with obliterative arteriosclerosis
undergoing thrombendarteriectomy and with advanced emphysema undergoing lung volume reduction surgery were examined using
scanning (SEM) and transmission (TEM) electron microscopy, and using immunofluorescence with monoclonal antibodies and antiserum
against chlamydiae. SEM shows spherical bodies (SBs) with a diameter from 0.3 μm to 0.6 μm on the surface of the alveoli and
bronchioles, as well as in atherosclerotic plaques. In atherosclerosis and emphysema, SBs reveal a double membrane, adherence
to collagen fibers, tissue destruction, as well as intracellular and interstitial localization in TEM. They show in parts
a densely packed central structure. SBs are seen both in alpha-1-antitrypsin deficiency emphysema and smoker’s emphysema.
Using immunofluorescence microscopy, spots are seen in corresponding distributions to the SBs. Morphological findings are
typical for aberrant chlamydiae seen in persistent infections. Chronic infection and bacterial colonization associated with
progressive disease seems to be relevant not only in atherosclerosis but also in pulmonary emphysema.
Received: 16 December 1999 / Accepted: 21 February 2000 / 相似文献
993.
Rainer Wessely Marc Vorpahl Albert Schmig Karin Klingel 《Cardiovascular pathology》2004,13(6):327-329
Constrictive pericarditis (CP) is a highly relevant disease clinically because pericardiectomy represents the only curative therapeutic approach. Previous cardiac surgery or mediastinal radiation may cause CP, however, infectious agents account for a substantial portion of CP. In this report, we present a patient with previous biopsy-proven myocarditis and positive seroconversion against coxsackievirus B3 without clinical evidence of acute pericardial involvement who developed CP after a prolonged period of time. This suggests that infectious particles primarily infecting the myocardium may lead to chronic inflammatory responses of the pericardium, thus causing CP even at late clinical stages. This case emphasizes the important fact that primary myocarditis may not only cause systolic ventricular impairment but may also induce diastolic dysfunction of the heart, either as restrictive cardiomyopathy or, as in this case, through inflammatory involvement of the pericardium, leading to CP. 相似文献
994.
Clinical implications of Mycobacterium kansasii species heterogeneity: Swiss National Survey 下载免费PDF全文
Taillard C Greub G Weber R Pfyffer GE Bodmer T Zimmerli S Frei R Bassetti S Rohner P Piffaretti JC Bernasconi E Bille J Telenti A Prod'hom G 《Journal of clinical microbiology》2003,41(3):1240-1244
Several subtypes of Mycobacterium kansasii have been described, but their respective pathogenic roles are not clear. This study investigated the distribution of subtypes and the pathogenicity of M. kansasii strains (n = 191) isolated in Switzerland between 1991 and 1997. Demographic, clinical, and microbiological information was recorded from clinical files. Patients were classified as having an infection according to the criteria of the American Thoracic Society. Subtypes were defined by PCR-restriction enzyme analysis of the hsp65 gene. Subtype 1 comprised 67% of the isolates (n = 128), while subtypes 2 and 3 comprised 21% (n = 40) and 8% (n = 15), respectively. Other subtypes (subtypes 4 and 6 and a new subtype, 7) were recovered from only 4% of patients (n = 8). M. kansasii subtype 1 was considered pathogenic in 81% of patients, while M. kansasii subtype 2 was considered pathogenic in 67% of patients and other subtypes were considered pathogenic in 6% of patients. The majority of patients with M. kansasii subtype 2 were immunocompromised due to the use of corticosteroids (21% of patients) or coinfection with HIV (62.5% of patients). Subtyping M. kansasii may improve clinical management by distinguishing pathogenic from nonpathogenic subtypes. 相似文献
995.
Anaemia-dermatitis of broilers: Field observations on its occurrence, transmission and prevention 总被引:2,自引:0,他引:2
Anaemia-dermatitis was first observed in German broiler flocks in 1977. Its frequency has increased in the past six years. Atrophy of thymus, bursa and bone marrow occur and are affected by a severe anaemia and immunosuppression. Secondary bacterial infections of the skin cause gangrenous dermatitis. Systematic investigations of outbreaks in two broiler integrations showed the syndrome to occur only in the offspring of young broiler breeders during the first 3 to 9 weeks of production. Anaemia could be reproduced experimentally in CAA-antibody negative SPF birds by injecting a bacteria-free filtrate of organ homogenates of diseased birds; birds kept in contact with the inoculated chicks remained healthy. It is concluded that anaemia-dermatitis is primarily caused by the chicken anaemia agent (CAA). Vertical transmission via hatching egg predominates with no evidence of horizontal transmission. In order to prevent egg transmission of CAA immunisation during rearing is indicated for breeder stocks. 相似文献
996.
Cutaneous malignant melanoma is a clinically and genetically heterogeneous disorder which is caused by an interaction between hereditary and environmental factors. In Sweden, a small portion of the inherited susceptibility is explained by the presence of germline mutations in the tumor suppressor gene CDKN2A. But still, the genetic background of melanoma susceptibility is largely unknown. Here, we conducted a genome-wide linkage scan on melanoma-prone families using high-density single-nucleotide polymorphisms (SNPs) arrays to identify novel melanoma susceptibility genes. We investigated 35 families of Swedish origin without CDKN2A mutations. Nonparametric and parametric multipoint linkage analyses were performed. After removal of SNPs in strong linkage disequilibrium, the strongest evidence of linkage was detected on chromosome 17p11-12 (logarithm (base 10) of odds (LOD) scores of 2.76) using parametric linkage analysis assuming a dominant trait with full penetrance. Analyses were also performed on a subset of families with low age at diagnosis (mean age ≤ 47 years), to obtain a more homogenous subset. This subgroup analysis based on 22 families yielded suggestive evidence of linkage to the chromosomal regions 11p12-p11 and 18q22 (multipoint LOD scores of 2.10 and 2.02, respectively). Also, the 17p region that was detected in the complete family set showed suggestive linkage in this cohort (multipoint LOD scores of 2.01). Our data suggest that these chromosomal regions, 17p12-p11 in particular as it was present in both analyses, may harbor genes involved in the susceptibility of malignant melanoma in the Swedish population. 相似文献
997.
Mechanism of NaCl secretion in rectal gland tubules of spiny dogfish (Squalus acanthias) 总被引:1,自引:0,他引:1
Rainer Greger Eberhard Schlatter 《Pflügers Archiv : European journal of physiology》1984,402(4):364-375
Rectal gland tubule (RGT) segments of the spiny dogfish (Squalus acanthias) were perfused in vitro. The effects of inhibitors of known mode of action on transepithelial PD (PDte resistance (Rte), the PD across the basolateral membrane (PDbl), the fractional resistance of this membrane (FRbl), and intracellular activities of NA+, Cl-, K+ (apha cell) were examined. Furosemide (5 x 10(-4) mol x 1(-1)) reduced PDte from -12 +/- 0.7 to -2.3 +/- 0.2 mV (n = 63), hyperpolarized PDbl from -71 +/- 1.3 to -79 +/- 0.9 mV (n = 59), FRbl decreased from 0.2 +/- 0.03 to 0.13 +/- 0.01 (n = 21), alpha cell cl- fell from 38 +/- 4 to 11 +/- 2 mmol x 1(-1) (n = 21), alpha cell Na+ fell from 37 +/- 4 to 17 +/- 2 mmol x 1(-1) (n = 12) and alpha cell K+ was constant [113 +/- 14 vs. 117 +/- 15 mmol x 1(-1) (n = 6)]. Furosemide exerted its effects within some 20-40s. Its action was completely reversible. Analysis of the time courses revealed that the furosemide induced initial fall in alpha cell cl- was approximately twice as rapid when compared to that of alpha cell Na+. Ba2+ 0.5 mmol x 1(-1) (bath) reduced PDte from -7.1 +/- 1.2 to -4.1 +/- 0.6 mV (n = 24), increased Rte from 18 +/- 2 to 22 +/- 2.5, omega cm2 (n = 14). PDbl depolarized from -75 +/- 2 to -48 +/- 2 mV (n = 42), FRbl increased from 0.2 +/- 0.02 to 0.34 +/- 0.04 (n = 14) and alpha cell K+ increased from 143 +/-28 to 188 +/- mmol x 1(-1) (n = 4). Ouabain (50 x 10(-6) mol x 1(-1), bath) reduced PDte from -12 +/-2 to -3 +/- 0.5 mV (n = 9), Rte increased from 18 +/- 3 to 21 +/- 3 omega cm2 (n = 5). PDbl depolarized from -67 +/- 4 to -26 + 3 mV (n = 14), FRbl increased from 0.23 +/- 0.04 to 0.45 +/- 0.05 (n = 6), alpha cell K+ fell only slightly from 135 +/- 15 to 112 +/- 30 mmol x 1(-1) (n = 4), but alpha cell cl- increased from 35 +/- 12 to 111 +/- 37 mmol x 1(-1) (n = 3). These effects of ouabain were slow when compared to those exerted by furosemide or Ba2+. The ouabain effects on PDte and PDbl were completely prevented if furosemide was applied first.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
998.
Rainer Kuhn Heinrich Alberts Herbert Bartl 《Macromolecular chemistry and physics.》1974,175(5):1471-1495
From theoretical considerations it is concluded that molecular weights and radii of gyration of the grafted chains in graft copolymers as well as the incompatibility of the grafted chains with the backbone polymer can be determined by light-scattering measurements in solution if the solvent used for these measurements is isorefractive with respect to the backbone polymer and if the weight fraction of the grafted chains is known. The new method for determining the incompatibility from anomalous Zimm-Diagrams is illustrated for mixtures of polystyrene and a chemically homogeneous ethylene/vinyl acetate random copolymer and is applied to fractions of the corresponding graft copolymers. The results of the light scattering measurements are compared with phase separation data from turbidimetric measurements. 相似文献
999.
Blood glucose measurement by infrared spectroscopy 总被引:2,自引:0,他引:2
For the development of an implantable artificial endocrine pancreas, a sensor for blood glucose measurement is needed providing a long-term stability. This goal can be achieved by the application of infrared spectroscopy which, unlike electrochemical sensors, responds directly to the glucose molecule. An investigation under physiological conditions revealed five glucose absorption bands in the near and middle infrared range. These are 1040, 1085, 1109, 1160 and 1365 cm-1. Only the 1040 cm-1 frequency coincides with none of the other infrared-active blood substances like proteins, lipids and urea. Nevertheless, the other absorption bands too, especially the 1109 cm-1 frequency, can be used for blood glucose measurement, if the superimposed absorptions are compensated. Methods for the compensation have been found. Technically feasible embodiments of an infrared glucose sensor are described. 相似文献
1000.
Construction and characterization of a single-chain antibody fragment derived from thymus of a patient with myasthenia gravis 总被引:12,自引:0,他引:12
Pathogenic anti-acetylcholine receptor (AChR) antibodies in myasthenia gravis (MG) and the corresponding animal model, experimental autoimmune myasthenia gravis (EAMG), principally recognize the main immunogenic region (MIR) of the AChR. Bivalent anti-MIR antibodies binding to the alpha-subunits of AChR result in AChR loss by antigenic modulation and complement activation. Monovalent Fab and single-chain variable fragments (scFv) of pathogenic anti-AChR antibodies can interfere with AChR binding of the pathogenic antibodies. In the present study, scFv637 was constructed from its parental Fab637, previously isolated from a thymus-derived phage display library with specificity toward anti-MIR of human AChR (hAChR), by PCR amplification. Bacterial produced scFv637 was able to bind to hAChR in standard precipitation radioimmunoassay (RIA). ScFv637 also bound to monkey AChR in situ on monkey neuromuscular junctions as showed in immunohistochemical staining. Furthermore, scFv637 was capable of inhibiting the binding of its intact IgG637 and anti-MIR mAb35 binding to hAChR up to 32.9 and 73.0%, respectively demonstrated in a competitive ELISA, and of MG patient sera from up to 45.5% in a competitive RIA. Therefore, scFv637, easier for manipulation in improvement of affinity and stability compared with its parental Fab637, may serve as an alternative candidate for specific immunotherapy in MG. 相似文献