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51.
Al-Maghrabi J Kamel-Reid S Jewett M Gospodarowicz M Wells W Banerjee D 《Archives of pathology & laboratory medicine》2001,125(3):332-336
CONTEXT: Primary lymphoma of the urinary bladder is rare. Only 84 cases have been reported in the English literature to date, and none of these cases has had molecular confirmation of clonal immunoglobulin gene rearrangement. OBJECTIVES: To review all cases with primary urinary bladder lymphoma in our records, to classify them using the REAL classification, to confirm their immunophenotype and genotype, and to determine their outcome. DESIGN: We identified 4 cases of primary urinary bladder lymphoma in our medical records from a 30-year period. Immunohistochemical detection of immunoglobulin light chains and molecular analysis of immunoglobulin heavy-chain genes using the polymerase chain reaction were performed on paraffin-embedded material. RESULTS: All patients were older than 60 years. The male-female ratio was 1:3. All patients had a history of chronic cystitis. Histologic features of mucosa-associated lymphoid tissue lymphoma with centrocyte-like cells, plasmacytoid B cells, or both were observed in all cases. Monoclonality of B cells was demonstrated by immunohistochemistry, polymerase chain reaction, or both methods in every case. All patients presented with stage IAE disease, were treated with radiotherapy alone, and have been in continuous complete remission for 2 to 13 years. CONCLUSIONS: Primary bladder lymphomas are usually of low-grade mucosa-associated lymphoid tissue type. They are more common in females and are associated with a history of chronic cystitis. Lymphoepithelial lesions are seen only in association with areas of cystitis glandularis. B-cell clonality is readily demonstrable by immunohistochemistry and/or polymerase chain reaction analysis. Local radiotherapy appears to confer long-term control. 相似文献
52.
Banerjee M Sanderson JD Spencer J Dunn-Walters DK 《Mechanisms of ageing and development》2000,115(1-2):85-99
It is thought that senescence of the immune system is responsible, at least in part, for many health problems associated with ageing. Previous studies on changes in lymphocyte composition have used flow cytometry to study peripheral blood lymphocytes (PBL's), or cells isolated from rodent tissue, and have yielded conflicting results. We have used immunohistochemistry to determine whether the B and T cells in human tissue from spleen and gut are affected by age. Areas of germinal centre, mantle zone and marginal zone of B cell follicles were measured. In addition, CD4 and CD8 T cells in T cell areas and in B cell follicles were counted. We observed a striking age-related decrease in the proportion of CD8+ T cells in the T cell zones of the spleen. This decrease was not apparent in the T cell population that occupies splenic B cell areas, or in GALT. Further differences, in CD4+ cells, were seen between T cell populations in the T cell zones and those in B cell areas. These findings highlight differences between lymphocyte populations in different lymphoid tissues, and different compartments within each tissue, which may be of importance in future studies of the ageing immune system. 相似文献
53.
54.
A case of primary large cell splenic lymphoma of B lineage exhibiting filiform cell appearance is reported. The patient presented with massive splenomegaly, and following spontaneous splenic rupture, died of adult respiratory distress syndrome. The clinical aspects of the case, notably a lymphoma arising as a primary tumour in the spleen, with spontaneous spleen rupture and rapid fatal outcome, in combination with the filiform appearance of the lymphoma on electron microscopic examination, constitute an unusual combination of features. As far as is known, this B cell neoplasm is only the second primary splenic lymphoma of filiform type to be recorded. 相似文献
55.
Hyaluronan-dependent pericellular matrices or "coats" are expressed by a variety of cell types in culture and modulation of their expression may be important in regulation of cell interactions in vivo during development. Monoclonal antibody IVd4, which recognizes hyaluronan-binding protein with the properties of a hyaluronan receptor, was shown to block formation of these coats by a variety of cells. Using rat fibrosarcoma cells, it was found that the antibody not only blocked initial formation of the coats but also caused their loss when added subsequent to formation. The loss of preformed coats in the presence of antibody occurred at 4 degrees and 37 degrees, implying that the function of hyaluronan-binding protein in coat formation is not in mediating metabolic processes. The antibody also had no significant effect on hyaluronan production by the fibrosarcoma cells. In addition, hyaluronan hexasaccharide, a competitive inhibitor of the interaction between polymeric hyaluronan and its cell surface receptor, was found to inhibit coat formation. Thus it is concluded that a hyaluronan-binding protein with the properties of a hyaluronan receptor is required for pericellular matrix formation. 相似文献
56.
Adenosine decreases post-ischaemic cardiac TNF-alpha production: anti-inflammatory implications for preconditioning and transplantation. 总被引:1,自引:0,他引:1
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D R Meldrum B S Cain J C Cleveland Jr X Meng A Ayala A Banerjee A H Harken 《Immunology》1997,92(4):472-477
Tumour necrosis factor-alpha (TNF-alpha) is an autocrine contributor to myocardial dysfunction and cardiomyocyte death in ischaemia-reperfusion injury (I/R), sepsis, chronic heart failure and cardiac allograft rejection. Cardiac resident macrophages, infiltrating leucocytes, and cardiomyocytes themselves produce TNF-alpha. Although adenosine reduces macrophage TNF-alpha production and protects myocardium against I/R, it remains unknown whether I/R induces an increase in cardiac TNF-alpha in a crystalloid-perfused model (in the absence of blood), and, whether adenosine decreases cardiac TNF-alpha and protects function after I/R. To study this, isolated rat hearts were crystalloid-perfused using the Langendorff method and subjected to I/R, with or without adenosine pretreatment. Post-ischaemic cardiac TNF-alpha (enzyme-linked immunosorbent assay and bioassay) and function were determined (Langendorff). I/R increased cardiac TNF-alpha and impaired myocardial function. Adenosine decreased cardiac TNF-alpha and improved post-ischaemic functional recovery. This study demonstrates that: first, I/R induces an increase in cardiac tissue TNF-alpha in a crystalloid-perfused model: second, adenosine decreases cardiac TNF-alpha and improves post-ischaemic myocardial function; third, decreased cardiac TNF-alpha may represent a mechanism by which adenosine protects myocardium; and fourth, adenosine-induced suppression of cardiac TNF-alpha may provide an anti-inflammatory link to preconditioning and have implications for cardiac allograft preservation. 相似文献
57.
Induction of capacitation in human spermatozoa in vitro by an endometrial sialic acid-binding protein 总被引:2,自引:0,他引:2
A Ca2+-dependent sialic acid-binding protein (SABP) of humanendometrium, which specifically bound to human sperm head plasmamembrane in vitro, was found to increase the percentage motilityand acrosome-reacted pattern of uncapacitated spermatozoa. Theprotein was synthesized in the endometrium and secreted intothe uterine fluid. This intra-uterine factor, which is apparentlyadvantageous in vitro in inducing human sperm capacitation,may play a significant role in promoting the postrelease maturationof ejaculated spermatozoa by enhancing 45Ca uptake into spermatozoaby a pathway which is insensitive to calcium-channel blockers.However, the 45Ca uptake could be enhanced on exposure to thedivalent cation ionophore A23187 and inhibited in the presenceof the calmodulin inhibitor trifluoperazine. The SABP also inducesan increase in intracellular Ca2+ in spermatozoa, as seen byFURA-2 AM studies. Furthermore, overlay studies show human SABPto be a Ca2+-binding protein. The data presented here suggestthat SABP induces invitro sperm capacitation and the subsequentacrosome reaction by increasing intracellular Ca2+ concentration. 相似文献
58.
Estimation of the rate of unrecognized cross-contamination with mycobacterium tuberculosis in London microbiology laboratories 总被引:2,自引:0,他引:2
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Ruddy M McHugh TD Dale JW Banerjee D Maguire H Wilson P Drobniewski F Butcher P Gillespie SH 《Journal of clinical microbiology》2002,40(11):4100-4104
Isolates from patients with confirmed tuberculosis from London were collected over 2.5 years between 1995 and 1997. Restriction fragment length polymorphism (RFLP) analysis was performed by the international standard technique as part of a multicenter epidemiological study. A total of 2,779 samples representing 2,500 individual patients from 56 laboratories were examined. Analysis of these samples revealed a laboratory cross-contamination rate of between 0.54%, when only presumed cases of cross-contamination were considered, and 0.93%, when presumed and possible cases were counted. Previous studies suggest an extremely wide range of laboratory cross-contamination rates of between 0.1 and 65%. These data indicate that laboratory cross-contamination has not been a common problem in routine practice in the London area, but in several incidents patients did receive full courses of therapy that were probably unnecessary. 相似文献
59.
60.
Saha S Mazumdar T Anam K Ravindran R Bairagi B Saha B Goswami R Pramanik N Guha SK Kar S Banerjee D Ali N 《Journal of clinical microbiology》2005,43(3):1269-1277
Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), caused by Leishmania donovani, is difficult, as the dermal lesions are of several types and resemble those caused by other skin diseases, especially leprosy. Since the disease generally appears very late after the clinical cure of kala-azar in India, it is also difficult to correlate PKDL with a previous exposure to L. donovani. Very few attempts have been made so far to diagnose PKDL serologically, and the diagnostic methods vary in their sensitivities and specificities. Diagnosis of PKDL through sophisticated PCR methods, although highly sensitive, has limited practical use. We have developed a serodiagnostic method using an enzyme-linked immunosorbent assay to detect specific immunoglobulin (Ig) isotypes and IgG subclass antibodies in the sera of Indian PKDL patients. Our assay, which uses L. donovani promastigote membrane antigens, was 100% sensitive for the detection of IgG and 96.7% specific for the detection of IgG and IgG1. Optical density values for individual patients, however, demonstrated wide variations. Western blot analysis based on IgG reactivity could differentiate patients with PKDL from control subjects, which included patients with leprosy, patients from areas where kala-azar is endemic, and healthy subjects, by the detection of polypeptides of 67, 72, and 120 kDa. The recognition patterns of the majority of serum samples from patients with PKDL were also distinct from those of the serum samples from patients with visceral leishmaniasis (VL), at least for a 31-kDa polypeptide. To further differentiate patients with PKDL from those with active and cured VL, we analyzed the specific titers of the Ig isotypes and IgG subclasses. High levels of IgG, IgG1, IgG2, and IgG3 antibodies significantly differentiated patients with PKDL from patients cured of VL. The absence of antileishmanial IgE and IgG4 in patients with PKDL differentiated these patients from those with active VL. These results imply intrinsic differences in the antibodies generated in the sera from patients with PKDL and VL. 相似文献