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81.
Transformed T lymphocytes infected by a novel isolate of human T cell leukemia virus type II 总被引:1,自引:0,他引:1
Chorba TL; Brynes R; Kalyanaraman VS; Telfer M; Ramsey R; Mawle A; Palmer EL; Chen AT; Feorino P; Evatt BL 《Blood》1985,66(6):1336-1342
Human T cell leukemia virus type II (HTLV-II) has been isolated from a patient (Mo) with features of leukemic reticuloendotheliosis (LRE) and from a patient with acquired immunodeficiency syndrome (AIDS). We have obtained another isolate of HTLV-II from a patient (CM) with severe hemophilia A, pancytopenia, and a 14-year history of staphylococcal and candidal infections but no evidence of T cell leukemia/lymphoma, AIDS, or LRE. Fresh mononuclear cells and cultured lymphocytes from CM express retroviral antigens indistinguishable by molecular criteria from HTLV-IIMo. Leukocyte cultures from CM yield hyperdiploid (48,XY, +2, +19) continuous lymphoid lines; human fetal cord blood lymphocytes (CBL) are transformed by cocultivation with these CM cell cultures but retain normal cytogenetic constitution. Electron microscopic examination of the CM cultures and transformed CBL reveals budding of extracellular viral particles, intracellular tubuloreticular structures, and viral particles contained within intracellular vesicles. CM cell cultures and the transformed CBL do not require exogenous interleukin 2, have T cell cytochemical features and mature T helper phenotypes, and exhibit minimal T helper and profound T suppressor activity on pokeweed mitogen-stimulated differentiation of normal B cells. These characteristics, which are similar to those observed with the first HTLV-II isolate, may represent properties of all HTLV-II-infected T cells. 相似文献
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A multidetector computed tomography (MDCT) was installed in our department. Referral rates, examination protocols and detection rates of abnormal findings in CT examinations for cervical spine trauma 6 months before and 6 months after MDCT installation were compared to look for changes in practice. Retrospective analysis of all CT cervical spine examinations in patients with multiple trauma over two contiguous 6-month periods: from July 2003 to December 2003 (helical CT) and from January 2004 to June 2004 (MDCT). Variables recorded were number of CT examinations performed, scan plane coverage and traumatic abnormalities detected. Phantom dosimetry measurements for cervical spine examination in both helical CT and MDCT were compared. One hundred and fifty four patients underwent cervical spine CT during these periods. Helical CT period: of 91 patients undergoing CT cervical spine examination for trauma, 65 (71%) were complete cervical examinations and 26 (29%) were level-specific examinations. Eight patients (9%) had cervical spine fracture, six of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 24.76, 1.86 and 0.21 mGy, respectively, for complete cervical spine examinations. MDCT period: of 63 patients who underwent CT cervical spine examination for trauma, 61 (97%) were complete examinations and 2 (3%) were level-specific examinations. Six patients (11%) had cervical spine fracture, three of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 75.8, 9.7 and 0.7 mGy, respectively, for complete cervical spine examinations, which were notably higher than those for helical CT. After installation of MDCT, clinical requests for complete examination of the cervical spine following trauma increased. This changing trend resulted in a significantly higher radiation dose to thyroid, lens and breast. 相似文献
85.
Strain JJ Karim A Caliendo G Alexis JD Lowe RS Fuster V 《General hospital psychiatry》2002,24(5):283-289
This is an update from the report-Cardiac Drug and Psychotropic Drug Interactions: Significance and Recommendations-published in this journal in November-December 1999. As mentioned in that article there has been an explosion of new drugs both in psychiatry and cardiology without a sufficient understanding of their potential interactions. Also there is a need for methods to update drug interactions on an ongoing basis. This report describes: 1) examples of actual adverse interactions from clinical cases that move beyond some of the hypothesized contraindications included in the 2000 millennium publication; 2) confirmation of previous adverse interactions reported if they strengthen the earlier findings; 3) listing of new drugs, e.g., sildenafil (viagra) now commonly prescribed by psychiatrists and cardiologists; 4) reports explaining and/or refining mechanisms of adverse interactions; and 5) cautions and important associated phenomenon of either a cardiac or a psychotropic drug, e.g., valproic acid and cases of life-threatening pancreatitis. Methods of publicizing the new knowledge of cardiac drug-psychotropic drug interactions, e.g., the Internet and web sites are described. 相似文献
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Iwan CC van der Horst Jan Paul Ottervanger Arnoud WJ van 't Hof Stoffer Reiffers Kor Miedema Jan CA Hoorntje Jan-Henk E Dambrink Marcel AT Gosselink Maarten WN Nijsten Harry Suryapranata Menko-Jan de Boer Felix Zijlstra 《BMC medicine》2005,3(1):1-10
Background
Stopping antipsychotic treatment can interrupt improvement and exacerbate the illness. The reasons for discontinuing treatment during controlled clinical trials were analyzed to explore this phenomenon.Methods
A post-hoc, pooled analysis was made of 4 randomized, double-blind clinical trials, 24–28 weeks in duration, involving 1627 patients with schizophrenia or a related disorder. Analyses combined all the atypical antipsychotic treatment groups in the studies.Results
The majority of patients (53%) stopped their treatment at an early stage. Poor psychiatric response along with worsening symptoms was the most frequently given reason for discontinuing the course (36%), which was substantially more common than discontinuation due to poor tolerability of the medication (12%). This phenomenon was corroborated by less improvement in patients who discontinued treatment compared with those who completed, based on the PANSS total scores. Discontinuation due to poor response was, apparently, more predominantly linked to patient perception than to physicians' conclusions alone (80% vs. 20%). Discontinuation due to patient perception of poor response appeared to occur particularly early in the course of treatment. Patients who discontinued due to poor toleration of the medication responded in a more comparable manner with completers.Conclusion
Discontinuing treatment may lead to exacerbation of symptoms, undermining therapeutic progress. In these studies, poor response to treatment and worsening of underlying psychiatric symptoms, and to a lesser extent, intolerability to medication were the primary contributors to treatment being discontinued. Our findings suggest that adherence may be enhanced by effective symptom control, as objectively measured and as subjectively perceived. Such strategies may improve patients' willingness to undertake long-term therapy and increase the likelihood of a better prognosis. 相似文献88.
89.
FMRP is associated to the ribosomes via RNA 总被引:8,自引:8,他引:8
Tamanini F; Meijer N; Verheij C; Willems PJ; Galjaard H; Oostra BA; Hoogeveen AT 《Human molecular genetics》1996,5(6):809-813
90.
Establishment of Unipolar Localization of IcsA in Shigella flexneri 2a Is Not Dependent on Virulence Plasmid Determinants 总被引:2,自引:0,他引:2
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Unipolar localization of IcsA on the surface of Shigella flexneri is required for efficient formation of actin tails and protrusions in infected eucaryotic cells. Lipopolysaccharide (LPS) mutations have been demonstrated to affect either the establishment or the maintenance of IcsA in a unipolar location, although the mechanism is unknown. In order to analyze the contribution of virulence plasmid determinants on the unipolar localization of IcsA, we examined the localization of IcsA expressed from a cloned plasmid copy in two different genetic backgrounds. The localization of IcsA was first examined in a virulence plasmid-cured derivative of the wild-type S. flexneri 2a isolate 2457T. This approach examined the contribution of virulence plasmid-borne factors, including the previously identified virulence plasmid-borne protease that is responsible for cleaving IcsA in the outer membrane and releasing the 95-kDa secreted form from the cell surface. IcsA localization in a related but nonpathogenic Escherichia coli strain expressing LPS of the O8 serotype was also examined. IcsA surface presentation in both of these genetic backgrounds continued to be unipolar, demonstrating that virulence plasmid-borne determinants are not responsible for unipolar localization of IcsA. The unipolar localization of IcsA in the E. coli background suggests that a common pathway that allows IcsA to be spatially restricted to one pole on the bacterial cell surface exists in Shigella and E. coli. 相似文献