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21.
JAK2T875N is a novel activating mutation that results in myeloproliferative disease with features of megakaryoblastic leukemia in a murine bone marrow transplantation model 下载免费PDF全文
Mercher T Wernig G Moore SA Levine RL Gu TL Fröhling S Cullen D Polakiewicz RD Bernard OA Boggon TJ Lee BH Gilliland DG 《Blood》2006,108(8):2770-2779
Acute megakaryoblastic leukemia (AMKL) is a subtype of acute myeloid leukemia associated with a poor prognosis. However, there are relatively few insights into the genetic etiology of AMKL. We developed a screening assay for mutations that cause AMKL, based on the hypothesis that constitutive activation of STAT5 would be a biochemical indicator of mutation in an upstream effector tyrosine kinase. We screened human AMKL cell lines for constitutive STAT5 activation, and then used an approach combining mass spectrometry identification of tyrosine phosphorylated proteins and growth inhibition in the presence of selective small molecule tyrosine kinase inhibitors that would inform DNA sequence analysis of candidate tyrosine kinases. Using this strategy, we identified a new JAK2T875N mutation in the AMKL cell line CHRF-288-11. JAK2T875N is a constitutively activated tyrosine kinase that activates downstream effectors including STAT5 in hematopoietic cells in vitro. In a murine transplant model, JAK2T875N induced a myeloproliferative disease characterized by features of AMKL, including megakaryocytic hyperplasia in the spleen; impaired megakaryocyte polyploidization; and increased reticulin fibrosis of the bone marrow and spleen. These findings provide new insights into pathways and therapeutic targets that contribute to the pathogenesis of AMKL. 相似文献
22.
Sex differences are prominent influences on spatial performance. One of the most common tasks to assess sex differences in spatial navigation in rodents is the Morris water task (MWT). In this task rats swim in a pool of water to locate a hidden platform employing the topographical relationships among the distal visual cues, pool wall, and goal location. Some evidence suggests that male rats display superior performance relative to females in the MWT. It is unknown, however, to what extent the sex difference in rats is task-dependent. This study compared the performance of male and female Long-Evans rats in the wet-land MWT versus the dry-land ziggurat task (ZT). The ZT represents a new dry-land task in which rats explore an arena with 16 ziggurat pyramids to locate food rewards. Several behavioural parameters, including latency, path length, path speed, probe trial performance, errors, and the number of returns were used as indices of spatial learning and memory. While males and females did not display significant differences in the traditional measures of spatial navigation within MWT, they displayed a robust sex difference in all measures of the ZT. These results indicate task-specific sex differences in spatial performance. Our findings suggest that males and females may employ different learning strategies in the MWT and ZT and that the latter task provides a more favourable task for assessing sex differences in rats. 相似文献
23.
Gerlinde R. Van de Walle Eric Cox Hans Nauwynck Herman W. Favoreel 《Reviews in medical virology》2009,19(6):338-358
Dendritic cells (DCs) play a critical role in orchestrating both innate and adaptive components of the immune system and are therefore of pivotal importance in the initiation of immune responses to control and eliminate viral infections. A major focus of this review is to give an overview on the recent findings that point out the importance of DCs in controlling alphaherpesvirus infections, but also indicate that these viruses have evolved several strategies to inhibit and/or exploit DC functions to delay or escape elimination by the immune system. In addition, we point out the common features and interspecies differences between DCs from man and animal, and discuss the potential use of animal alphaherpesvirus homologues to gain further insights into the interaction between alphaherpesviruses and DCs in their natural virus–host environment. Finally, recent knowledge on the potential of alphaherpesviruses as vectors for DC stimulation and their use for immunotherapy is presented. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
24.
Klaus Schmitt Gerald Tulzer Michael Merl Gerlinde Aichhorn Andrea Grillenberger Gabriele Wiesinger Günther Hofstadler 《European journal of pediatrics》1995,154(3):201-204
Doxorubicin and daunorubicin are effective anticancer agents in children, however, their therapeutic value is limited by myocardial cardiotoxicity. In 14 children (median age 5,0 years, range 3–12) prospective studies were performed using pulsed Doppler echocardiography to assess the changes in left ventricular systolic and diastolic filling dynamics. None of these children developed cardiomyopathy. M-mode echocardiographic systolic parameters and Doppler transmitral flow velocities were analysed at baseline, after a cumulative anthracycline dose of 138±26 mg/m2 (second examination) and after 240±15 mg/m2 (third examination). At the second examination the acceleration time/ejection time ratio was significantly reduced (P<0.01), but this was no longer evident at the third examination. There was no significant change of peak velocity over aortic valve, preejection period and change of velocity over time. In contrast, three diastolic parameters changed significantly; the late over early inflow velocity (P<0.05), mitral valve late time velocity integral (P<0.01 at the second andP<0.05 at the third examination) and the ratio A-TVI/TVI (P<0.025 andP<0.01). At the third examination the velocity of the A wave was also significantly increased.Conclusion In anthracyline treated children left ventricular diastolic function deteriorates before systolic function. Diastolic function parameters should be used rather than systolic parameters to monitor these patients. 相似文献
25.
To identify patients at high risk of life-threatening infections, we retrospectively analysed the prevalence of infectious complications in 187 chronic lymphocytic leukaemia patients treated in our institution since 1999 and correlated them with clinical features. A questionnaire with detailed questions regarding infectious complications was mailed to patients and their general practitioners. Major infections (requiring intravenous antibiotics or inpatient treatment) were reported in 37 patients (19.8%) and minor infections (requiring oral antibiotics and outpatient treatment) in 113 patients (60.4%). Univariate analysis identified advanced disease (P = 0.02), gender (P = 0.01), duration of disease (P = 0.007), number of previous chemotherapy regimens (P < 0.001), previous therapy with purine analogues and monoclonal antibodies (P < 0.001; P = 0.019), massive splenomegaly (P = 0.03), low granulocyte count (P < 0.001), low serum immunoglobulin concentration (P = 0.005), low haemoglobin concentration (P < 0.001) and high serum lactate dehydrogenase (LDH) concentration (P < 0.001) as risk factors for major infections. In multivariable logistic regression analysis, only the number of previous chemotherapy regimens (risk ratio [RR] = 1.8; 95% confidence interval [CI] 1.2-8.0) and haemoglobin concentration (RR = 0.6; CI 0.5-0.8) remained significant for major infections. The number of previous chemotherapy regimens was the only independent risk factor for minor (RR = 7.6; CI 2.2-25.7) and varicella-zoster virus infections (RR = 2.1; CI 1.3-3.4). In untreated patients, the only risk factor for major infections was LDH concentration. Patients treated with purine analogues or autologous stem cell transplantation had a higher risk of developing viral infections. In conclusion, disease activity and pretreatment extent have a stronger impact on the risk of severe infectious complications than hypogammaglobulinaemia. Preferably, prophylactic strategies should be evaluated in patients defined by these parameters. 相似文献
26.
BACKGROUND: Cutaneous manifestations of B-cell chronic lymphocytic leukemia (B-CLL) comprise a wide spectrum of clinicopathologic presentations. In some cases, onset of skin lesions is triggered by antigenic stimulation, and specific skin infiltrates at sites of previous herpes simplex or herpes zoster infection have been well documented. Specific skin manifestations of B-CLL can also be observed at sites typical for lymphadenosis benigna cutis (nipple, scrotum, earlobe), a Borrelia burgdorferi-associated cutaneous B-cell pseudolymphoma. METHODS: We studied specific skin manifestations of B-CLL arising at sites typical for B. burgdorferi-induced lymphadenosis benigna cutis, analyzing tissues for presence of B. burgdorferi DNA using the polymerase chain reaction (PCR) technique. Six patients with B-CLL (M : F = 4 : 2; mean age: 67.8) presented with specific skin lesions located on the nipple (four cases) and scrotum (two cases). RESULTS: Clinically there were solitary erythematous plaques or nodules. Histology revealed in all cases a dense, monomorphous infiltrate of small lymphocytes showing an aberrant CD20+/CD43+ phenotype. In all cases monoclonality was demonstrated by PCR analysis of the JH gene rearrangement. PCR analysis showed in four of the six cases the presence of DNA sequences specific for B.burgdorferi. CONCLUSIONS: Our study demonstrates that infection with B. burgdorferi can trigger the development of specific cutaneous infiltrates in patients with B-CLL. 相似文献
27.
Gerlinde Spencer 《Australian Occupational Therapy Journal》1977,24(3):8-15
The following treatment mode was developed as a team effort in the psychiatric unit of Royal North Shore Hospital. We have found this approach so useful that it seems of value to pass it on. Basically it could be described as the use of manual activity and Gestalt techniques in a group setting. 相似文献
28.
Rau T Wohlleben G Wuttke H Thuerauf N Lunkenheimer J Lanczik M Eschenhagen T 《Clinical pharmacology and therapeutics》2004,75(5):386-393
OBJECTIVE: Treatment with antidepressants is frequently associated with adverse effects or insufficient clinical response. Several antidepressants are metabolized by cytochrome P450 (CYP) 2D6. The activity of this enzyme markedly varies among individuals from poor to ultrarapid metabolism on the basis of the polymorphism of the CYP2D6 gene. This association study investigated whether the CYP2D6 genotype distribution differs from that of the German white population either in patients with marked adverse effects or in nonresponders during treatment with antidepressants metabolized by CYP2D6. METHODS: By use of a retrospective, naturalistic approach, outpatient practices and hospitals in southern Germany were asked to report on patients who either had had adverse drug effects or were nonresponsive during treatment with CYP2D6-dependent antidepressants. CYP2D6 genotyping was performed by a panel of polymerase chain reaction techniques. Poor and intermediate metabolizer alleles, as well as allelic duplications of CYP2D6, were detected. RESULTS: Of 28 patients with adverse effects during treatment with a CYP2D6-dependent antidepressant, 8 (29%) had 2 inactive alleles and thus were poor metabolizers. This is a 4-fold increase as compared with the German population (P <.0001). Amplification of fully functional alleles (associated with ultrarapid metabolism) was found in 3 (19%) of the 16 nonresponders (approximately 5.0-fold higher in nonresponders than in the population) (P =.0012). CONCLUSION: The results suggest that the CYP2D6 genotype is associated with the occurrence of adverse effects and clinical nonresponse in psychiatric patients treated with CYP2D6-dependent antidepressants. 相似文献
29.
Effects of verteporfin therapy on central visual field function 总被引:5,自引:0,他引:5
Schmidt-Erfurth UM Elsner H Terai N Benecke A Dahmen G Michels SM 《Ophthalmology》2004,111(5):931-939
PURPOSE: To evaluate the effect of photodynamic therapy with verteporfin on the maintenance of central visual field function. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: Forty-six consecutive patients with subfoveal choroidal neovascularization (CNV) caused by age-related macular degeneration including a classic component were randomly assigned. Thirty-three participants received standard verteporfin therapy, and 13 received placebo and laser treatment. METHODS: The trial was performed as a single-center, double-masked study. Patients were examined before therapy and continuously in 3-month intervals during 2 years of follow-up. A scanning laser ophthalmoscope (SLO) was used to perform macular microperimetry. Absolute and relative scotomas were documented at each visit, and size was measured in square millimeters. MAIN OUTCOME MEASURES: The change in size of central scotoma in the verteporfin group compared with the placebo group. RESULTS: An absolute scotoma was seen in 88%, and a relative scotoma was seen in 100% of eyes before therapy. Absolute defects were associated with the classic CNV component localized angiographically. In the verteporfin group, the absolute scotoma grew from 2.5 mm(2) at baseline to a final size of 7.3 mm(2) at month 24. In the placebo group, the mean lesion size of the absolute scotoma enlarged from an initial size of 2.7 mm(2) to 31.5 mm(2) after 24 months. The relative scotoma increased from 7.9 mm(2) at baseline to 20.8 mm(2) at month 24 in the verteporfin group, whereas a progression from 8.5 mm(2) initially to 48.3 mm(2) at the final presentation was measured in the placebo group. Statistical analysis showed that both the mean absolute and relative scotoma sizes were significantly smaller in the verteporfin group than the placebo group for all intervals from 6 to 24 months (P<0.001). CONCLUSIONS: Documentation of macular function with SLO perimetry demonstrated a significant benefit of verteporfin therapy for the preservation of the central visual field. Absolute and relative scotoma sizes remained smaller after therapy. This may influence reading ability and visual rehabilitation. 相似文献