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81.
R Karttunnen E J Breese J A Walker-Smith T T MacDonald 《Journal of clinical pathology》1994,47(11):1015-1018
AIMS--To determine the prevalence of cells secreting interleukin-4 (IL-4) in the gut mucosa of children with chronic inflammatory bowel disease. METHODS--Mononuclear cells were isolated from intestinal biopsy specimens from control children (n = 10) and children with active inflammatory bowel disease (Crohn's disease n = 15, ulcerative colitis n = 9, indeterminate colitis n = 3). Spontaneous IL-4 production was then measured by SPOT-enzyme linked immunosorbant assay (ELISA) using a pair of non-competing anti-IL-4 monoclonal antibodies. The percentage of T cells in the isolated cells were also determined and the prevalence of IL-4 secreting cells calculated per 10,000 T cells. RESULTS--In control children the mean number of IL-4 secreting cells was 15.1 per 10,000 T cells. In Crohn's disease and ulcerative colitis the means were 5.3 and 5.2, respectively. In two children with indeterminate colitis numbers were also low. There was no difference in the percentage of T cells in the cell preparations isolated from each patient group. The reduction of IL-4 secreting cells in patients with Crohn's disease was not caused by steroids. CONCLUSIONS--In idiopathic inflammatory bowel disease IL-4 secreting cells are reduced in diseased mucosa. 相似文献
82.
Renal biopsies from 44 patients with steroid sensitive nephrotic syndrome were examined with respect to the content of their intraglomerular platelets and compared with 18 normal control patients and with 51 patients with membranous glomerulonephritis and the nephrotic syndrome. The results suggested that platelet activity was not involved in the pathogenesis of steroid sensitive nephrotic syndrome; in the active phase of the number of platelets in glomeruli is lower than that of normal controls, and this may be associated with increased sensitivity to aggregating agents as part of the nephrotic syndrome. After steroid treatment and disappearance of proteinuria, the number of intraglomerular platelets rises to normal values. 相似文献
83.
Recombinant alpha2(IV)NC1 domain inhibits tumor cell-extracellular matrix interactions, induces cellular senescence, and inhibits tumor growth in vivo
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Roth JM Akalu A Zelmanovich A Policarpio D Ng B MacDonald S Formenti S Liebes L Brooks PC 《The American journal of pathology》2005,166(3):901-911
Cellular interaction with the extracellular matrix is thought to be a critical event in controlling angiogenesis and tumor growth. In our previous studies, genetically distinct noncollagenous (NC) domains of type-IV collagen were shown to interact with integrin receptors expressed on the surface of endothelial cells. Moreover, these NC1 domains were shown to inhibit angiogenesis in vivo. Here, we provide evidence that a recombinant form of the alpha2(IV)NC1 domain of type-IV collagen could bind integrins alpha1beta1 and alphavbeta3 expressed on melanoma cells and inhibit tumor cell adhesion in a ligand-specific manner. Systemic administration of recombinant alpha2(IV)NC1 domain potently inhibited M21 melanoma tumor growth within full thickness human skin and exhibited a dose-dependent inhibition of tumor growth in nude mice. Interestingly, alpha2(IV)NC1 domain enhanced cellular senescence in tumor cells in vitro and in vivo. Taken together, these results suggest that recombinant alpha2(IV)NC1 domain is not only a potent anti-angiogenic reagent, but it also directly impacts tumor cell behavior. Thus, alpha2(IV)NC1 domain represents a potent inhibitor of tumor growth by impacting both endothelial and tumor cell compartments. 相似文献
84.
Staphylococcal toxic shock toxin specifically binds to cultured human epithelial cells and is rapidly internalized. 总被引:2,自引:3,他引:2
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Staphylococcal toxic shock syndrome toxin (TST) was labeled with 125I under mild conditions without apparent destruction of the molecule. [125I]TST bound specifically to human epithelial (Chang) cells in culture; the binding was inhibited by a 100-fold excess of unlabeled toxin. Scatchard analysis of the binding data indicated about 10(4) receptor sites per cell and a dissociation constant (Kd) of 4 X 10(-9) M. When cells pretreated with TST at 4 degrees C were swiftly transferred to 37 degrees C, the amount of surface-bound toxin rapidly declined, as determined by release of noninternalized label from the cell surface. Half-time (t1/2) of internalization was about 1.5 min. Ultrastructural studies showed that toxin labeled with ferritin-conjugated antibodies entered the cytoplasm via coated pits forming coated vesicles in the first 2 min of incubation at 37 degrees C. The coated vesicles coalesced with transport vesicles that are ultrastructurally unlike receptosomes. Thus, the unusual ultrastructural pattern of this internalization suggests that TST is initially internalized by receptor-mediated endocytosis and then enters an alternate pathway involving translocation in special transport vesicles, perhaps to other cells. 相似文献
85.
Cellular adhesion molecules play a central role in leucocyte migration through peripheral blood and tissues. A crucial stage in these events in selectin-mediated adhesion involving E-selectin expressed on activated endothelium interacting with a range of carbohydrate ligands expressed by specific subpopulations of leucocytes. As such mechanisms may be relevant to bone marrow-derived dendritic epidermal Langerhans' cell (LC) migration, expression of these carbohydrate ligands was assessed immunocytochemically in whole skin biopsies and in epidermal cell suspensions obtained from adult humans. Double-labelling experiments revealed that sialyl Lewis x, recognized by the monoclonal antibody CSLEX1, was expressed on epidermal LC (n = 9). Furthermore, expression was enhanced at 24 hr following epicutaneous application of antigen and in the inflammatory disorder psoriasis (n = 10). E-selectin was concomitantly strongly expressed on dermal endothelium in psoriasis and allergic contact dermatitis. Intradermal injection of the T-cell-derived cytokine interferon-gamma (IFN-gamma) led to increased LC expression of sialyl Lewis x. In epidermal cell suspensions, in contrast to keratinocytes, CD1a+ cells expressed sialyl Lewis x, intensity of which was enhanced after 4 days in culture. CSLEX1 staining could be abolished and CD15 (non-sialated Lewis x) expression induced by saponification and treatment with neuraminidase. Expression of other selectin ligands was also examined. While the cutaneous lymphocyte antigen defined by the monoclonal antibody HECA-452 reacted with a small minority of LC, sialyl Lewis a and sulphatide were not expressed under any experimental conditions. These studies indicate that E-selectin-sialyl Lewis x interactions are potentially important in LC migration, both into and out of skin. 相似文献
86.
Rhodri Ceredig H. Robson MacDonald Eric J. Jenkinson 《European journal of immunology》1983,13(3):185-190
The phenotypic properties of lymphoid cells in the developing embryonic thymus were characterized using monoclonal antibodies and flow microfluorometry. CBA/J-T6/T6 thymocytes stained with antibodies directed against Thy-1.2, Lyt-1, Lyt-2 or H-2Kk were simultaneously analyzed for fluorescence intensity and forward light scatter (FLS), a cell size-related parameter. Whereas Thy-1 and Lyt-1 antigens were already present on 15-day fetal thymocytes, Lyt-2 expression was first detectable on day 16 and increased rapidly thereafter to reach adult levels by day 19. Concomitant with these phenotypic changes, rapid changes in FLS occurred during this time period. The FLS distribution of Lyt-2+ cells was initially homogeneously high (day 16) but became biphasic at days 17–18. Thereafter, the lower FLS subpopulation predominated. FLS changes in Lyt-2? cells could be dissociated kinetically from changes in the Lyt-2+ subpopulation. Thus high FLS Lyt-2? cells were the predominant subpopulation throughout the entire fetal period and could still be detected after birth, when a population with lower FLS first appeared. The embryonic thymus developing in vivo was then compared with the 13-day embryonic thymus maintained for 14 days in an in vitro organ culture system. Based on a combination of fluorescence and FLS analysis, the organ-cultured thymus appeared to share certain phenotypic properties with the 18–19 day in vivo developing thymus. 相似文献
87.
Development of automated immunoassays for immune status screening and serodiagnosis of rubella virus infection 总被引:4,自引:0,他引:4
G G Abbott J W Safford R G MacDonald M C Craine R R Applegren 《Journal of virological methods》1990,27(2):227-239
The fully automated IMx immunoassay analyzer was used to develop a system for the detection of IgG and IgM antibodies to rubella virus for immune status screening and diagnosis of primary infections. Reagents and assay protocol software were developed using rubella virus sensitized microparticles as the solid phase to capture specific antibodies from serum samples. Anti-human IgG or IgM antibody coupled to alkaline phosphatase enzyme followed by methylumbelliferyl phosphate substrate was used to detect the presence or absence of antibodies specific to the antigens on the solid phase. To evaluate the efficacy of the IMx rubella IgG assay, immune status screening was performed with a clinical patient population of 501 sera. When compared to an IgG specific enzyme immunoassay and passive hemagglutination assay the agreement was greater than 99%. The IMx rubella IgM assay was utilized to determine the presence of rubella specific IgM antibodies in 462 sera. These results were compared to IgM specific enzyme immunoassay results and also demonstrated greater than 99% agreement. Seroconversion following rubella vaccination of susceptible individuals was demonstrated by IgG and IgM antibody responses as early as two weeks postvaccination. In addition to automation, the IMx system offers rapid assay times and calibration curve storage without sacrificing clinical efficacy. 相似文献
88.
Studies of the association of the A, B and Lewis blood group antigens with carcinoembryonic antigen (CEA) 总被引:1,自引:0,他引:1
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Carcinoembryonic antigen (CEA) was purified from primary tumour or from hepatic metastases obtained from ten cases of carcinoma of the colon. In nine cases the blood group antigens A, B, Lea or Leb were detected in CEA preparations by the binding of 125I-labelled CEA by blood group antibodies. The extent of binding appeared to preclude simple contamination of CEA preparations by blood group glycoprotein. In all cases the blood group antigens detected were consistent with the patients' known blood groups. Blood group I and i activities were not detected.
It is concluded that the determinants of A, B and Lewis antigens and of CEA share the same glycoprotein carrier molecules.
相似文献89.
Body weight and food intake of lean and obese, male and female Osborne-Mendel rats following treadmill exercise were compared. Rats were assigned, separately by sex, to one of three diet groups; Group 1 was fed a low fat (10%) diet throughout the study, Group 2 was fed a high fat (55%) diet for 16 weeks and then switched to the low fat diet 1 week prior to exercise, and Group 3 was fed the high fat diet throughout the study. To control for differences in work output between the leanest and heaviest animals, exercise intensity was adjusted across groups such that all exercised rats had equivalent energy expenditure. After a 3 day training period, the exercise was successively increased over 8 days until a work output of 374.9J was reached. Relative to their respective controls, obese exercised males showed a reduction in body weight but no change in food intake. In contrast, exercised females showed no change in body weight or food intake, regardless of dietary condition. 相似文献
90.