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21.
1. A new histochemical method is described for arylsulfatase activity (ASA)in hemic cells and organ imprints. Some common limitations in histochemicaltechnics have been tested and appear to be minimized in this method.2. With the present method, a wide series of hemic cells may be identified,and their ASA separately graded from 0-4.3. A study has been made of normal ASA values in all series of humanhematopoietic cells and of neutrophilic granulocyte ASA in common laboratory animals. Eosinophils, megakaryocytes, and neutrophils have the highestASA. Increases in ASA occur early during cell maturation in neutrophils andeosinophils.4. Humans have a higher ASA than the laboratory animals tested. Withincertain species, there is some general correlation between neutrophilic granulocyte ASA and ASA of other organs. Under these conditions, leukocyte ASAis a potentially useful general screening method for ASA.5. Some factors which enhance or inhibit leukocyte ASA have been tested. Submitted on August 15, 1960 Accepted on November 5, 1960 相似文献
22.
K. KRISHNAN C.W. ROSS P.L. BOCKENSTEDT P.T. ADAMS 《International journal of laboratory hematology》1997,19(2):105-109
Autoimmune neutropenia (AIN) is characterized by antibody mediated peripheral destruction of neutrophils. Since there is no effective treatment, antibiotics have to be used frequently for recurrent infections. Five selected patients with serologically proven AIN were treated with r-metHuG-CSF at 5–8 μg/kg body weight (300–480 μg) daily; the dose and frequency of r-metHuG-CSF was reduced after neutrophil counts above 1.0×109/l were obtained. R-metHuG-CSF is effective in AIN and causes a sustained rise in ANC which can be maintained on a low dose administered twice or thrice weekly. 相似文献
23.
24.
PETER D. SKILLINGTON DAVID C. McGIFFIN RICHARD KEMP J. H. N. BETT GEOFFREY HOLT ROSS FORGAN-SMITH 《Internal medicine journal》1988,18(7):872-873
A 30 year old veterinary surgeon developed a febrile illness with serological evidence of Brucellosis. He was known to have aortic valve disease and during the course of the illness, the clinical features of endocarditis became evident, with a vegetation visible echocardiographically on the aortic valve. Because of persisting fever despite appropriate antibiotic therapy, aortic valve replacement with a viable cryopreserved allograft aortic valve was undertaken. Organisms consistent with Brucella species were demonstrated in the excised vegetation. The patient received a six week course of antibiotics and his post-operative course was uneventful. 相似文献
25.
RUNJAN CHETTY KAREN PULFORD MARGARET JONES DANIELE MATHIEU-MAHUL PAULINE CLOSE SONAY HUSSEIN GORM PALLESEN ELIZABETH RALFKIAER HARALD STEIN KEVIN GATTER DAVID MASON 《The Journal of pathology》1996,178(3):311-315
Fifty formalin fixed, paraffin-embedded cases of T-acute lymphoblastic leukaemia (T-ALL) from 12 bone marrow trephines and 38 lymph nodes were stained with a new monoclonal antibody, 2TL 242, raised against recombinant TAL1 protein. The antibody recognizes TAL-1 polypeptides of molecular weight 39 and 41 kD (full length). In addition, a variety of other leukaemias and lymphomas were also stained with 2TL 242. Twenty-four of the 50 cases of T-ALL showed nuclear positivity, ranging from 10 to 90 per cent of leukaemic cells. A positive staining reaction was nuclear and stippled in pattern. Nuclear staining was not seen in any other type of leukaemia or lymphoma. Five cases of follicular lymphoma showed diffuse cytoplasmic staining of variable intensity. Although some background staining is obtained with this antibody, positive nuclear staining is easily distinguishable. This monoclonal antibody has a potential role in primary diagnosis and in the detection of minimal residual disease in T-ALL. 相似文献
26.
JEFFREY H. PLOCHOCKI JOSE R. RODRIGUEZ‐SOSA BRENT ADRIAN SAUL A. RUIZ MARGARET I. HALL 《Clinical anatomy (New York, N.Y.)》2016,29(8):1053-1058
Modern anatomical and surgical references illustrate perineal muscles all innervated by branches of the pudendal nerve but still organized into anatomically distinct urogenital and anal triangles with muscles inserting onto a central perineal body. However, these conflict with the anatomy commonly encountered during dissection. We used dissections of 43 human cadavers to characterize the anatomical organization of the human perineum and compare our findings to standard references. We found bulbospongiosus and the superficial portion of the external anal sphincter (EAS) were continuous anatomically with a common innervation in 92.3% of specimens. The superficial transverse perineal muscle inserted anterior and lateral to the midline, interdigitating with bulbospongiosus. The three EAS subdivisions were anatomically discontinuous. Additionally, in 89.2% of our sample the inferior rectal nerve emerged as a branch of S3 and S4 distinct from the pudendal nerve and innervated only the subcutaneous EAS. Branches of the perineal nerve innervated bulbospongiosus and the superficial EAS and nerve to levator ani innervated the deep EAS. In conclusion, we empirically demonstrate important and clinically relevant differences with perineal anatomy commonly described in standard texts. First, independent innervation to the three portions of EAS suggests the potential for functional independence. Second, neuromuscular continuity between bulbospongiosus and superficial EAS suggests the possibility of shared or overlapping function of the urogenital and anal triangles. Clin. Anat. 29:1053–1058, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
27.
Previous studies have shown that an optimal humoral response to a primary protein antigen requires C3 and CR2 (CD21). Sera from non-immunized donors contain natural IgM and IgG antibodies to the primary antigen keyhole limpet haemocyanin (KLH), and these have been previously shown to form immune complexes (IC) that activate the classical pathway of C, fixing iC3b/C3dg onto the KLH antigen. Such KLH IC bind to CR2 on KLH-non-specific B lymphocytes, resulting in antigen processing and MHC class II-dependent presentation to KLH-specific helper T cells. KLH IC also induce B lymphocytes to express the CD80 co-stimulatory molecule via simultaneous CR2 ligation with C3 and FcγRII (CD32) stimulation by IgG natural antibody. The current study demonstrated that KLH IC ligation to either CR2 or FcγRII resulted in activation of a second co-stimulatory molecule, LFA-1 (CD11a, CD18). The possibility of polyclonal B cell stimulation by the presentation of KLH-iC3b/C3dg by antigen-non-specific B cells was excluded by demonstration that in vitro cultivation of peripheral blood mononuclear cells (PBMC) with KLH-iC3b/C3dg elicited only anti-KLH, and did not stimulate synthesis of antibodies to hepatitis C virus (HCV) or tetanus toxoid (TT). Of greatest significance, a specific anti-KLH response was only detectable in cultures stimulated with KLH-iC3b/C3dg and not in cultures stimulated with KLH alone or KLH-IgG. Thus, iC3b/C3dg that was bound to a primary protein antigen enhanced recognition and specific immunoglobulin synthesis by antigen-specific B cells, even though the antigen was taken up and processed via CR2 by both antigen-specific and non-specific B cells. 相似文献
28.
JUAN C. DE LA TORRE MARGARET MALLORY MICHELLE BROT LISA GOLD GEORGE KOOB MICHAEL B. A. OLDSTONE ELIEZER MASLIAH 《Virology》1996,220(2):508
Neurons have a restricted expression of MHC heavy chain molecules which prevents presentation of antigens of infecting viruses. As a result, such infected cells escape immune surveillance and allow the establishment of noncytolytic persistent infection. Here we show that a chronic noncytolytic viral infection bothin vitroandin vivoselectively perturbed the expression of GAP-43, a protein that plays a central role in neuronal plasticity processes accompanying learning and memory. GAP-43 expression was greatly decreased in the hippocampus, an area of heightened viral replication, while synaptic density was preserved. Concurrently, the ability to learn tasks was significantly impaired in these persistently infected mice. Yet, infected neurons remained free from structural injury. 相似文献
29.
V. V
TVIKA M. HANIKÝOV J. V
TVIKOV G. D. ROSS 《Clinical and experimental immunology》1999,115(2):229-235
Phagocyte and NK cell CR3 functions as both an adhesion molecule and an iC3b receptor mediating cytotoxic responses to microorganisms. Cytotoxic activation of iC3b receptor function requires ligation of both a CD11b I-domain site for iC3b and a lectin site located in the C-terminus of CD11b. Because tumours lack the CR3-binding polysaccharides of bacteria and fungi, iC3b-opsonized tumours do not stimulate CR3-dependent cytotoxicity. Previous studies showed that NK cells could be induced to kill iC3b-opsonized tumours with small soluble β-glucans that bound with high affinity to CR3, bypassing the absence of similar polysaccharides on tumour membranes. Because CR3 signalling requires several tyrosine phosphorylation events, it appeared possible that CR3-dependent killing of autologous tumour cells might be suppressed by NK cell inhibitory receptors for MHC class I (KIR and CD94/NKG2) whose action involves recruitment of SHP-1 and SHP-2 tyrosine phosphatases. In the current study, Epstein–Barr virus (EBV)-transformed B cells were used as targets following opsonization with iC3b. Soluble β-glucan primed CR3 for killing of iC3b-coated B cells, but autologous class I-bearing targets were 84% more resistant than class I-deficient Daudi cells. Blockade of target cell class I with a MoAb specific for a domain recognized by both KIR and CD94/NKG2 resulted in comparable killing of class I+ B cells. By contrast, another MoAb to class II had no effect on cytotoxicity. These data suggest that NK cell recognition of class I suppresses CR3/tyrosine kinase-dependent cytotoxicity in the same way as it suppresses cytotoxicity mediated by other tyrosine kinase-linked receptors such as FcγRIIIA (CD16). 相似文献
30.
Herpes simplex virus type 2 (HSV-2) is a sexually transmitted pathogen that infects the genital tract. Efforts to develop vaccines to protect women against this and other sexually transmitted pathogens would be facilitated by a better understanding of the immune mechanisms that protect the female reproductive tract against such infections. Such information would be invaluable in developing vaccine strategies to promote the type and magnitude of immune responses in the genital tract that would effectively protect against infection. This review focuses on recent studies using a progestin-treated adult mouse model to explore mucosal immunity to HSV-2 in the vagina. Evidence indicating a major role for both humoral and T cell immunity is presented. 相似文献