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71.
Urban Sester Barbara C. Gärtner Heinrike Wilkens Bernhard Schwaab Rolf Wössner Ingrid Kindermann Matthias Girndt reas Meyerhans Nikolaus Mueller-Lantzsch Hans-Joachim Schäfers Gerhard W. Sybrecht Hans Köhler Martina Sester 《American journal of transplantation》2005,5(6):1483-1489
Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation. 相似文献
72.
Results of pulmonary resection for lung cancer in Norway, patients older than 70 years. 总被引:7,自引:0,他引:7
Hans Rostad Anne Naalsund Trond-Eirik Strand Randi Jacobsen Olaug Talleraas Jarle Norstein 《European journal of cardio-thoracic surgery》2005,27(2):325-328
OBJECTIVE: Surgical resection for lung cancer is the mainstay of curative treatment, but studies regarding postoperative results and long term outcome in the elderly have differed. The purpose of the present study was to assess the early and long-term results of surgical resection in patients more than 70 years of age. METHODS: In Norway all clinical and pathologic departments submit reports on cancer patients to the Cancer Registry of Norway. This investigation included all patients more than 70 years of age resected for lung cancer in the time period 1993-2000. For results of long-time follow-up only patients operated on between 1993 and 1998 were included. RESULTS: A total of 763 patients (541 men) were identified aged 71-87 years. Postoperative mortality rate was 9%, highest after bilobectomy and pneumonectomy. The most commonly reported causes of postoperative death were pneumonia and cardiac complications. The majority of patients had tumor categorized as clinical stage (cStage) Ia and Ib. More than 100 in each of these groups proved to have more advanced disease postoperatively (pStage). The 5-year relative survival rate was significantly better in patients with disease in pStage I compared to higher stages. Women had a significantly better 5-year survival rate compared to men, 62.8 and 35.7%, respectively. CONCLUSIONS: Lung cancer surgery appears to be a relatively safe procedure even in the elderly. There is a high postoperative mortality after bilobectomy and pneumonectomy. However, when old people survive the postoperative period the long term prognosis seems favorable. 相似文献
73.
Effect of early and late antibiotic treatment in experimental acute pancreatitis in rats 总被引:1,自引:0,他引:1
Michael Schwarz Bertram Poch Rainer Isenmann Dietrich Kriese Eva Rozdzinski Hans G. Beger Frank Gansauge 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(3):365-370
Background The clinical course in acute necrotizing pancreatitis is mainly determined by bacterial infection of pancreatic and peripancreatic
necrosis. The effect of two antibiotic regimens for early and late treatment was investigated in the taurocholate model of
necrotizing pancreatitis in the rat.
Materials and methods Seventy male Wistar rats were divided into five pancreatitis groups (12 animals each) and a sham-operated group (10 animals).
Pancreatitis was induced by intraductal infusion of 3% taurocholate under sterile conditions. Animals received two different
antibiotic regimes (20 mg/kg imipenem or 20 mg/kg ciprofloxacin plus 20 mg/kg metronidazole) early at 2, 12, 20, and 28 h
after induction of pancreatitis or late at 16 and 24 h after induction of pancreatitis or no antibiotics (control). Animals
were examined after 30 h for pancreatic and extrapancreatic infection.
Results Early and late antibiotic treatment with both regimes could significantly reduce pancreatic infection from 58 to 8–25%. However,
extrapancreatic infection was only reduced by early antibiotic therapy. While quinolones also reduced bacterial counts in
small and large bowel, imipenem did not.
Conclusions In our animal model of necrotizing pancreatitis, early and late treatment with ciprofloxacin/metronidazole and imipenem reduce
bacterial infection of the pancreas. Extrapancreatic infection, however, is reduced significantly only by early antibiotic
treatment. The effectivity of early antibiotic treatment in the clinical setting should be subject to further investigation
with improved study design and sufficient patient numbers. 相似文献
74.
75.
Bauer Thomas R. Jr; Schwartz Barbara R.; Conrad Liles W.; Ochs Hans D.; Hickstein Dennis D. 《Blood》1998,91(5):1520-1526
76.
Hans Knecht Pierre Brousset Edith Bachmann Gorm Pallesen Bernhard F. Odermatt 《Leukemia & lymphoma》1994,15(5):399-403
Two recently discovered genes, the recombination activating genes 1 and 2 (RAG-1 and RAG-2), are necessary to perform variable (V), diversity (D), and joining (J) recombination. They synergistically activate VDJ recombination to generate immunocompetent lymphocytes. Disruption of either gene results in a maturation arrest at a very early B and T cell progenitor stage. Expression and downregulation of RAG's are closely associated with interleukin 7, sIgM and TCR-CD3 complex, respectively. Assessment of RAG mRNA expression is a valuable marker in identifying the genotypic maturation status of leukemias and lymphomas. Persistent RAG expression in otherwise mature lymphoid proliferations may explain puzzling biological and clinical observations such as multiple rearrangements in lymphomas with a mature phenotype. Lack of RAG expression in Hodgkin's disease with abundant Reed-Stern-berg cells is consistent with a mature phenotype of the latter. Availability of a anti-RAG-1 monoclonal antibody in the near future will facilitate RAG analysis of lymphomas. 相似文献
77.
78.
79.
Hans Brunner Thomas C Wetter Birgit Hogl Alexander Yassouridis Claudia Trenkwalder Elisabeth Friess 《Movement disorders》2002,17(5):928-933
We investigated non-rapid eye movement (non-REM) sleep in patients with newly diagnosed Parkinson's disease (PD) who had never previously received dopaminergic medication. There were no significant differences in the conventional sleep parameters between de novo patients with PD and a healthy control group, but the length of stage 1 sleep and the number of awakenings increased significantly upon administration of dopaminergic drugs. Analyzing the quantitative electroencephalogram (EEG), we observed a significant reduction in the low-delta frequency range and a nonsignificant increase in the sigma frequency range in de novo patients with PD. The dopaminergic medication also nonsignificantly reduced the low-delta and sigma frequencies, the latter to the level of the controls. Possible mechanisms that may account for the observed differences are discussed. It is suggested that Parkinson's disease as well as the application of dopaminergic drugs exerts a desynchronizing effect on the sleep EEG that is reflected in a disruption of sleep continuity. 相似文献
80.
Hans Fisher Ph.D. 《Nutrition reviews》1992,50(6):170-171
This study showed that, in chickens, the negative effects of phytate-phosphorus in a low inorganic phosphorus diet could be completely reversed through the additive effects of reduced dietary calcium and increased cholecalciferol. In the future, perhaps greater reliance on more readily available plant phosphorus sources may be instituted in developing countries, where cheap sources of inorganic phosphorus are difficult to obtain. 相似文献