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1.
Jocivania O da Silva Renata S Fernandes Fábio K Ticli Clayton Z Oliveira Maurício V Mazzi Jo?o J Franco Silvana Giuliatti Paulo S Pereira Andreimar M Soares Suely V Sampaio 《Toxicon》2007,50(2):283-291
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies. 相似文献
2.
In order to clarify the physiological role in vivo of H2O2-detoxifying enzymes at low and high levels of O2 tension we studied catalase (CAT), glutathione peroxidases (GP), and in vivo peroxidation (TBA-RS) in the lung and heart of Rana perezi frogs chronically treated with hyperoxia, aminotriazole (AT) -a CAT inhibitor-, or both. Hyperoxia did not change CAT, GP or TBA-RS. Aminotriazole caused an almost complete depletion of CAT, a 30% decrease of GP and a 132% (lung) to 200% (heart) increase of TBA-RS. Changes similar to these were found in the group treated with AT in hyperoxia. No mortality or changes in total or organ weight occurred in the experimental groups. Main conclusions are: (1) The maximal hyperoxia tolerance showed by frogs among vertebrates does not need antioxidant enzyme induction from lung or heart and is probably related to the presence of high constitutive levels of GP in relation to metabolic rate. (2) Even in normoxia the tissues present significant amounts of H2O2, and CAT is needed to avoid oxidative damage. GP does not compensate its absence. The implications of these results in relation to oxygen toxicity in man is discussed. 相似文献
3.
Franco Rilke M. D. F. R. C. Umberto Veronesi M. D. Alberto Luini M. D. Cristina Brambilla M. D. Viviana Galimberti M. D. Stefano Zurrida M. D. Silvana Pilotti M. D. M. I. A. C. Silvana Di Palma M. D. Roberto Zucali M. D. Laura Lozza M. D. 《The breast journal》1996,2(3):176-180
Abstract: Breast conservation surgery is an effective and safe treatment for many breast carcinomas. It may be possible to further limit the extent of resection (or expand the indication for breast conservation) by the application of preoperative chemotherapy and radiotherapy. We explored the feasibility of this in a pilot study.
Seventy-three patients (mean age 48, 63% premenopausal) with confirmed breast cancer, less than 2.5 cm, received chemotherapy (Group A) or chemotherapy plus radiotherapy (Group B) prior to limited resection (tumorectomy). Axillary dissection was always performed. Results: In 6/31 (19%) Group A and 17/42 (40%) Group B patients the tumor was not palpable after preoperative treatment, with complete pathological remission in 1 and 3 cases respectively. Histologic grading, mitosis, cellular alteration, and cellularity evaluations indicated a consistently greater therapeutic effect with chemoradiotherapy than with chemotherapy alone.
In conclusion, radiotherapy appears useful in the preoperative treatment of breast cancer and its use in association with various drug combinations should be further explored. 相似文献
Seventy-three patients (mean age 48, 63% premenopausal) with confirmed breast cancer, less than 2.5 cm, received chemotherapy (Group A) or chemotherapy plus radiotherapy (Group B) prior to limited resection (tumorectomy). Axillary dissection was always performed. Results: In 6/31 (19%) Group A and 17/42 (40%) Group B patients the tumor was not palpable after preoperative treatment, with complete pathological remission in 1 and 3 cases respectively. Histologic grading, mitosis, cellular alteration, and cellularity evaluations indicated a consistently greater therapeutic effect with chemoradiotherapy than with chemotherapy alone.
In conclusion, radiotherapy appears useful in the preoperative treatment of breast cancer and its use in association with various drug combinations should be further explored. 相似文献
4.
Peter M. Ravdin Stephanie Green James H. Doroshow Silvana Martino 《Investigational new drugs》1994,12(4):333-336
Summary Thirty-two eligible patients with advanced metastatic breast cancer who had received no more than 1 prior chemotherapy regimen for metastatic disease (16 had received prior doxorubicin) were treated with piroxantrone at a dose of 120 mg/m2 intravenously every 21 days. In the twenty-seven patients evaluable for response, two partial responses were seen. Toxicities observed were primarily hematologic with grade 3 or greater granulocytopenia occurring in 34% of the patients. One patient developed symptomatic congestive heart failure at a total cumulative dose of 960 mg/m2. We conclude that piroxantrone given at this dose and schedule has minimal activity in patients with metastatic breast cancer. 相似文献
5.
José I. Bilbao Manuel Ruza Jesús M. Longo Francisco Mansilla Antonio Picardi Vanessa de Villa Fernando Pardo Jesús Sola Jorge Quiroga 《Cardiovascular and interventional radiology》1994,17(4):210-213
Posttransplant lymphoproliferative disorders are infrequent tumors related to chronic immunosuppressive therapy. We present a liver transplant recipient who developed such a tumor in the porta hepatis that provoked obstruction of the entire portal triad. Treatment consisted of systemic chemotherapy, percutaneous dilatation, and placement of Wallstent endoprostheses across both biliary and portal vein stenoses. The patient died 3 weeks later of pneumonia and sepsis. At necropsy, the tumor was completely necrosed and the prostheses in both the common bile duct and the portal vein were patent. 相似文献
6.
Mohand Mesbah Ilka Nemere Petros Papagerakis Jean-Raphael Nefussi Silvana Orestes-Cardoso Catherine Nessmann Ariane Berdal 《Journal of bone and mineral research》2002,17(9):1588-1596
The calciotropic hormone 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] has been established to control skeletal tissue formation and biomineralization via the regulation of gene expression. This action involves the well-characterized nuclear 1,25(OH)2D3 receptor. However, it has been recognized that several cellular responses to 1,25(OH)2D3 may not to be related to the exclusive nuclear receptor. Indeed, this secosteroid is able to generate rapid responses that have been proposed to be mediated by interactions of the ligand, which is a putative cell membrane-associated rapid-response steroid (MARRS) binding protein for 1,25(OH)2D3 [1,25D3-MARRS]. The nongenomic pathway of 1,25(OH)2D3 was studied here in detail by immunolocalization of the 1,25D3-MARRS during the specific context of human prenatal development. Western blotting with proteins extracted from 4 week- to 27-week-old embryos was performed, evidencing a 65-kDa molecular species recognized by antibody Ab 099 generated against synthetic peptides corresponding to the N terminus of the 1,25D3-MARRS from chick intestinal basolateral membranes. Based on this biochemical conservation of protein in the human species, the temporospatial expression patterns were established in the craniofacial skeleton at the same ages. Comparative analysis was performed in teeth and bones from early morphogenesis to terminal cell differentiation and extracellular biomineralization. The data show the potential implication of 1,25D3-MARRS in the heterogeneous cell population including ameloblasts, odontoblasts, osteoblasts, and osteoclasts. The epithelial-mesenchymal cascade related to odontogenesis was coincident with a sequence of up- and down-regulation of immunoreactive 1,25D3-MARRS. Biomineralization was associated with a striking up-regulation in the adjoining secretory cells in all tissues. Finally, osteoclasts appeared also to express the 1,25D3-MARRS during these early phases of bone modeling. Previously obtained data of the nuclear vitamin D receptor (VDR) expression and this study on 1,25D3-MARRS suggest the existence of cross-talk between the genomic and nongenomic pathways during human development. 相似文献
7.
Giuseppe Galardi Silvestro Micera Jacopo Carpaneto Silvana Scolari Massimo Gambini Paolo Dario 《Movement disorders》2003,18(11):1358-1367
We developed an automated and objective method to measure posture and voluntary movements in patients with cervical dystonia using Fastrack, an electromagnetic system consisting of a stationary transmitter station and four sensors. The junction lines between the sensors attached to the head produced geometrical figures on which the corresponding aspects of the head were superimposed. The head position in the space was reconstructed and observed from axial, sagittal, and coronal planes. Four patients with cervical dystonia and 6 healthy subjects were studied. Each patient was representative of one of the typical patterns of cervical dystonia. The study allowed the authors to collect quantitative data on posture and range of motion of the head. This pilot study demonstrates the efficacy of the Fastrack system to objectively measure the head position in cervical dystonia patients. 相似文献
8.
9.
Marcos Barbosa-Ferreira Maria Lúcia Zaidan Dagli Paulo César Maiorka Silvana Lima Górniak 《Food and chemical toxicology》2005,43(4):497-503
Senna occidentalis (So) is a weed that grows in pastures along fences and in fields cultivated with cereals such as corn and soybean, and many reports have been showing intoxication with this plant in different animal species. It is also used in many medicinal purposes. The objective of the present study was to better evaluate the toxic effects of prolonged administration of So seeds to rats. Forty male Wistar rats were divided into four groups of 10 animals each, three of them respectively fed rations containing 1%, 2% and 4% So seeds, and the last one (control) fed commercial ration for a period of 2 weeks. Fourteen rats were also used in a pair-feeding (PF) experiment. The rats of the experimental groups showed lethargy, weakness, recumbency, depression and emaciation. Two rats of the 4% group and two of the PF group died during the experiment. Histopathological study showed fiber degenerations in the skeletal (Tibial, pectoral and diaphragm) and cardiac muscles. In the liver parenchyma, was observed vacuolar degeneration and, in the kidney, mild nefrosis in the proximal convoluted tubules. All of these alterations occurred in a dose-dependent fashion. Moderate to severe degeneration and spongiosis in the central nervous system, especially in cerebellum. Electron microscopy revealed mitochondrial lesions in all analyzed tissues. 相似文献