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991.
992.
BACKGROUND: This 15-month study was designed to compare the effect of skin surface temperature on skin pigmentation following a single intralesional or contact cryosurgical treatment of keloids. PATIENTS/METHODS: Thirty Caucasian patients with 45 keloids present for more than 6 months were included in this study. Twenty-one keloids were treated by the contact method while the remaining 24 scars were managed using an intralesional cryosurgery technique. The skin surface temperature at the keloids was measured and recorded using a Ni/Cd thermocouple. Four variables of the thermal history were evaluated with the contact and the intralesional methods, namely cooling rate, hold time, end temperature and thawing rate. Assessment of the local hypopigmentation was performed 6 months after the treatment using a pigmentation scale. RESULTS: Significantly slower cooling (6.09 +/- 4.56 degrees C/min) and thawing rates (54.52 +/- 32.17 degrees C/min) were recorded with the intralesional cryosurgery method when compared with the cooling rates (13.47 +/- 9.04 degrees C/min) and thawing rates (89.00 +/- 86.42 degrees C/min) of the contact method (P < 0.000001). The end temperature of the contact technique was significantly cooler (-46.77 +/- 14.74 degrees C) when compared with that of the intralesional method (-15.55 +/- 6.77 degrees C) (P < 0.000001). There was a trend for the hold time of intralesional cryosurgery to be longer (82.67 +/- 138.03 s) than that of the contact method (16.86 +/- 23.49 s) (P < 0.059). A significant difference in skin pigmentation was demonstrated between the two cryosurgical methods. In 91.7% of the keloids treated by the contact technique a significant hypopigmentation was noticed, while no marked hypopigmentation was detected in the skin surface of the keloids treated by the intralesional method (P < 0.0001). CONCLUSION: We hypothesize that the thermal history of the skin surface during the intralesional cryosurgery technique provides a better survival environment for the melanocytes than the contact method, thus producing a lower rate of permanent hypopigmentation and disfiguring.  相似文献   
993.
994.
BACKGROUND: Transfusion-related acute lung injury (TRALI) is clinically similar to the adult respiratory distress syndrome (ARDS) and has been linked to the transfusion of leukocyte antibodies in blood components. Animal model have implicated neutrophil (PMN)-priming agents in ARDS; however, two agents were required. Previous studies showed the generation of PMN-priming agents during blood storage. Thus the association of PMN-priming agents with TRALI was examined. STUDY DESIGN AND METHODS: Ten patients with TRALI and 10 with febrile or urticarial reactions (control group) were evaluated. The presence of PMN-priming activity was tested in the patients' pretransfusion and posttransfusion blood samples by incubating PMNs with these samples followed by activation of the respiratory burst. Plasma lipids were separated by normal-phase high-performance liquid chromatography (HPLC), and the priming activity was evaluated. The presence of leukocyte antibodies was determined in the blood donors and patients with TRALI. RESULTS: Significantly more PMN-priming activity was present in the posttransfusion sera (11.4 +/? 1.8 nmol superoxide anion/min, mean +/? SEM; n=10) and plasma of patients with TRALI than in their pretransfusion sera (6.5 +/? 1.5: n=10) or in the pretransfusion and posttransfusion sera (5.1 +/? 1.3, n=10; and 4.5 +/? 1.4, n=10, respectively) and from the controls (p < 0.05). HPLC separation of lipids demonstrated that three active species were present in the posttransfusion plasma samples of TRALI patients. All the patients with TRALI had underlying clinical factors, such as infection, cytokine administration, recent surgery, or massive transfusion, while only 2 of 10 control patients had these clinical conditions. None of the donors had significant titers of HLA or HLA-DR antibodies; however, 50 percent had weak positivity for granulocyte antibodies. CONCLUSION: TRALI is the result of two clinical events, the first being a predisposing clinical condition and the second being the transfusion of biologically active lipids in stored blood.  相似文献   
995.
Objectives. Minocycline is a tetracycline antibiotic increasingly recognized in psychiatry for its pleiotropic anti-inflammatory and neuroprotective potential. While underlying mechanisms are still incompletely understood, several lines of evidence suggest a relevant functional overlap with retinoic acid (RA), a highly potent small molecule exhibiting a great variety of anti-inflammatory and neuroprotective properties in the adult central nervous system (CNS). RA homeostasis in the adult CNS is tightly controlled through local RA synthesis and cytochrome P450 (CYP450)-mediated inactivation of RA. Here, we hypothesized that minocycline may directly affect RA homeostasis in the CNS via altering local RA degradation. Methods. We used in vitro RA metabolism assays with metabolically competent synaptosomal preparations from murine brain and human SH-SY5Y neuronal cells as well as viable human SH-SY5Y neuroblastoma cell cultures. Results. We revealed that minocycline potently blocks RA degradation as measured by reversed-phase high-performance liquid chromatography and in a viable RA reporter cell line, even at low micromolar levels of minocycline. Conclusions. Our findings provide evidence for enhanced RA signalling to be involved in minocycline's pleiotropic mode of action in the CNS. This novel mode of action of minocycline may help in developing more specific and effective strategies in the treatment of neuroinflammatory or neurodegenerative disorders.  相似文献   
996.
  • Endovascular devices to treat stroke will continue to improve
  • Stroke care is suboptimal with IV TPA with such a narrow treatment window
  • Interventional cardiologists should be involved in stroke care with appropriate training.
  相似文献   
997.
  • Over 90% of patients achieve adequate levels of platelet inhibition with both Prasugrel and Ticagrelor.
  • The introduction of Prasugrel was met with some hesitation from physicians because of the significant increase in cost.
  • This pharmaceutically sponsored and authored retrospective study suggests that both agents are effective.
  相似文献   
998.
The Competence Network “Acute and Chronic Leukemias” was founded in 1997 by the consolidation of the leading leukemia study groups in Germany. Key results are the development of new trials and cooperative studies, the setup of patient registries and biobanking facilities, as well as the improvement of study infrastructure. In 2003, the concept of the competence network contributed to the foundation of the European LeukemiaNet (ELN). Synergy with the ELN resulted in cooperation on a European and international level, standardization of diagnostics and treatment, and recommendations for each leukemia and interdisciplinary specialty. The ultimate goal of the network is the cure of leukemia through cooperative research.  相似文献   
999.
Long-term treatment of lupus nephritis with cyclosporin A   总被引:9,自引:0,他引:9  
We evaluated the efficacy and safety of long-term treatment with cyclosporin A (CSA) in type IV lupus nephritis. Seventeen patients with biopsy-proven WHO type IV lupus nephritis were enrolled in a prospective, open study. Twelve of the 17 completed 48 months of treatment with CSA and prednisolone. Three patients required the addition of azathioprine, at 12, 38 and 47 months, respectively, for cutaneous disease flare with refractory rashes. One patient was lost to follow-up at 40 months. The mean +/- SD duration of treatment was 43.2 +/- 10.1 months (range 15.7-48 months). A significant reduction of proteinuria and a significant rise in serum albumin were noted 1 month after initiation of treatment. Improvement was maintained throughout the study except for three patients who relapsed with recurrence of nephrotic syndrome. There were no significant changes in serum creatinine level or creatinine clearances throughout the study. Repeat renal biopsy at 12 months following treatment with CSA showed histological improvement, with WHO type II changes in all 17 patients accompanying significant reduction in activity indices. Patients with baseline haemoglobin (Hgb) levels < 12 g/dl showed significant improvement. Serum C3 and C4 levels were not changed significantly. Corticosteroid-sparing effects were noted. Side-effects included hypertension, gum hypertrophy and mild hirsuitism, but were not serious. Combination therapy using CSA and prednisone is effective and safe for long-term treatment in lupus patients with WHO type IV nephritis.   相似文献   
1000.
Twenty plateletpheresis components were harvested from 11 healthy donors and stored in polyolefin bags on a horizontal flatbed agitator at 22 degrees C. After 24 hours, white cells were reduced in one aliquot by centrifugation while the other aliquot was stored unaltered. Samples were obtained aseptically from each of these platelets at intervals for up to 10 days, and measurements were made of platelet glycoprotein Ib (GPIb) by both flow cytometry and polyacrylamide gel electrophoresis, of ristocetin-induced platelet aggregation by impedance aggregometry, and of plasma and platelet von Willebrand factor (vWF) by enzyme-linked immunosorbent assay. Storage of platelets under these conditions was associated with only minor decreases in surface GPIb, intraplatelet vWF, and ristocetin-induced platelet aggregation, and no differences were observed between the white cell-reduced and nonreduced aliquots. No benefit of white cell reduction in such components before prolonged storage is evident in the vWF-platelet interaction.  相似文献   
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