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71.
72.
Mun M Kohno T Miyanaga S Fujimori S 《Kyobu geka. The Japanese journal of thoracic surgery》2005,58(5):392-395
We report 2 cases of thoracoscopic resection for patients with Mycobacterium avium complex (MAC). A 25-year-old female was referred to our hospital because of abnormal shadows in the right lower lung field on chest X-ray. Her chest computed tomography (CT) showed that the lesion was localized in the right lower lobe. She was given a diagnosis of MAC by polymerase chain reaction (PCR) of sputum. Thoracoscopic lobectomy was performed after chemotherapy for 10 months. A 64-year-old female was referred to our hospital because of hemoptysis. Bronchiectasis had been diagnosed in her since the age of 35 years, and then she was given a diagnosis of secondary MAC. Her chest CT showed bronchiectasis, and consolidations were localized in the superior segment of the right lower lobe. Then superior segmentectomy of the right lower lobe under video-assisted thoracoscopic surgery (VATS) was performed. It was reported that surgical intervention is indicated in patients with MAC, when persistent hemoptysis is seen or chemotherapy is ineffective. If the lesion is localized, lung resection under VATS may be a good option in selected patients. 相似文献
73.
BaCKGROUND: Due to the aging general population, deceased donors > or =55 years will form an increasingly larger proportion of the deceased kidney donor pool. METHODS: Using data from the United States Renal Data System, we determined the change in graft survival between 1996 and 2000 among 32,557 recipients of donors aged <55 years and > or =55 years in univariate and multivariate survival analyses. We identified donor risk factors for graft loss that might influence the decision to accept or reject donors <55 and > or =55 years. The initial glomerular filtration rate established 6 months after transplantation (initial GFR), and the stability of GFR in the first post-transplant year (GFR at 12 months post-transplantation-GFR at six months post-transplantation) were compared between recipients of donors <55 and > or =55 years and the association of these factors with graft survival was determined. RESULTS: In 2000, one-year graft survival in donors > or =55 years was 86.7%. Between 1996 and 1999 the projected graft half life improved from 11.4 to 14.5 years for recipients of donors <55 years (P < 0.01); however, there was no improvement for recipients of donors > or =55 years (8.2 to 9.2 year, P= 0.46). Among donor factors studied, only cold ischemic time >24 hours identified recipients of donors > or =55 years at risk for graft loss. Compared to recipients of donors <55 years, recipients of donors > or =55 years established a lower initial GFR (42 vs. 56 mL/min/1.73 m(2), P < 0.0001), and had less stable GFR in the first post-transplant year (-1.5 vs. -0.6 mL/min/1.73 m(2), P <.0001). Recipients from donors > or =55 years with initial GFR > or =50 mL/min/1.73 m(2) and no drop GFR during the first post-transplant year had graft survival that was superior to that of donors <55 years with either initial GFR <50 mL/min/1.73 m(2) or a drop in GFR during the first post-transplant year. CONCLUSION: Donors > or =55 years are a valuable resource. Despite improvements in immunosuppression, rejection, and delayed graft function, the projected increase in long-term graft survival among recipients of donors <55 years was not shared among recipients of donors > or =55 years. Recipients of donors > or =55 years had lower initial GFR, and less stable GFR during the first post-transplant year. Limiting cold ischemic time to <24 hours may improve outcomes among recipients of donors > or =55 years. Future studies to maximize initial GFR and minimize early loss of GFR in recipients of donors > or =55 years may lead to improved outcomes from deceased donors > or =55 years. 相似文献
74.
75.
Nagaraj A Kim H Hamilton AJ Mun JH Smulevitz B Kane BJ Yan LL Roth SI McPherson DD Chandran KB 《Medical engineering & physics》2005,27(2):147-156
OBJECTIVE: A novel methodology has been developed to evaluate regional alterations in arterial wall material properties with induced atheroma in an animal model. METHODS: Atheromatous lesions (fatty, fibro-fatty, and fibrous) were induced in the carotid arteries of a Yucatan miniswine model by endothelial cell denudation and high cholesterol diet. The images at base line and 8 weeks after denudation were obtained using intravascular ultrasound (IVUS) imaging along with hemodynamic data. Finite element analysis (FEA) along with optimization was employed to assess regional alterations in elastic modulus in the presence of atheroma confirmed by histology. RESULTS: In animals with 8 weeks of induced atherosclerosis, the elastic modulus increased-(elastic modulus-all values x 10(4) Pa, mean+/-S.D.) normal elements (9.34+/-0.36) compared to abnormal elements (9.52+/-0.36) (p<0.05 versus normal elements). Wall thickness increased with atheroma formation. These data demonstrate stiffening vascular wall elastic modulus with lesion progression. This is different from the behavior of femoral arteries, where the elastic modulus decreases with early stages of atheroma development followed by an increase as lesions progress. CONCLUSIONS: This methodology permits determination of areas with early atheroma development, follow atheroma progression, and potentially evaluate interventions aimed at decreasing atheroma load and normalizing vascular material properties. 相似文献
76.
Yoshito Andou Mikio Yasutake Jae‐Mun Jeong Haruo Nishida Takeshi Endo 《Macromolecular chemistry and physics.》2005,206(17):1778-1783
Summary: Gas‐phase assisted surface polymerization (GASP) of methyl methacrylate (MMA) and styrene (St) was investigated with Fe‐based radical initiating systems, FeCl2/2,2′‐bipyridine (Bpy)/methyl α‐bromophenylacetate (MBPA), etc. GASP with these initiating systems proceeded to produce corresponding polymers on substrate surfaces. The resulting PMMA had very high PDI values, suggesting an uncontrolled reaction. In an attempt to control the GASP, polymerization with a simple initiating system, Fe(0)/MBPA, was examined on Fe(0)‐metal surfaces, resulting in significant polymerization activity to produce high‐molecular‐weight PMMA. The results of time‐course tests on GASP of MMA and St suggested that a change had taken place to produce physically controlled propagation sites on the Fe(0) powder surfaces.
77.
Inhibition of erythropoietin activity by cyanate 总被引:2,自引:0,他引:2
Park KD Mun KC Chang EJ Park SB Kim HC 《Scandinavian journal of urology and nephrology》2004,38(1):69-72
OBJECTIVE: Increased urea concentration is a measure of advanced renal failure and the adequacy of renal replacement therapy in end-stage renal disease (ESRD). Altered biologic activity due to changes in protein structure occurs when cyanate, formed spontaneously from urea, reacts with proteins. Carbamylation results in impaired erythropoietin (EPO) activity when high concentrations of cyanate react with EPO. In this study, the activity of carbamylated EPO (C-EPO), formed at a cyanate concentration which may occur in vivo, was studied in Sprague-Dawley rats. MATERIAL AND METHODS: The extent of carbamylation, causing loss of free amino groups, was monitored using trinitrobenzenesulfonic acid. Erythrocyte, hemoglobin, hematocrit and leukocyte levels were measured after either EPO, incubated EPO, C-EPO, physiologic saline or cyanate (1.5 microM; 0.2 ml) were injected subcutaneous twice weekly for 3 weeks in rats. RESULTS: In vitro carbamylation of EPO was time- and concentration-dependent. C-EPO concentration increased as the duration of exposure to cyanate increased from 6 to 72 h, or as cyanate concentration increased from 15 nM to 1.5 microM. Injections of EPO caused significant increases in vivo in all erythropoietic measures. In contrast, injections of C-EPO, physiologic saline or 1.5 microM cyanate caused no change from baseline. CONCLUSIONS: These results demonstrated diminished biologic activity in healthy rats by C-EPO formed in vitro at cyanate concentrations that may be found in vivo. C-EPO and high urea-derived cyanate levels may contribute to suboptimal erythropoietic responses to EPO therapy for chronic renal failure and ESRD, and may provide another measurement indicating inadequate dialysis. 相似文献
78.
Effect of artificial cells on hepatic function after ischemia-reperfusion injury in liver 总被引:5,自引:0,他引:5
Chang EJ Lee SH Mun KC Suh SI Bae JH Kim SP Choi HJ Cho KB Hwang JS 《Transplantation proceedings》2004,36(7):1959-1961
BACKGROUND: The liver suffers from ischemia/reperfusion injury during transplantation. Reactive oxygen species generated by xanthine oxidase during reperfusion of the ischemic liver may be partially responsible for the hepatic injury. Oxygen free radicals are removed by antioxidant enzymes such as superoxide dismutase (SOD), catalase, and glutathione peroxidase. Using glutaraldehyde and lysine we constructed crosslinked hemoglobin, containing SOD and catalase, and assessed its ability to protect against ischemia/reperfusion injury during transplantation. METHODS: In contrast to the sham-operated control groups, blood was exchanged using crosslinked hemoglobin (polyHb) a PolyHb-SOD-catalase (PSC) group. After ischemia/reperfusion injury, several parameters of hepatic damage and oxygen free radicals were measured as well as microscopic examination. RESULTS: Alanine aminotransferase, aspartate aminotransferase, superoxide production, hydrogen peroxide, and malondialdehyde levels were higher among the PolyHb group than sham-operated controls. The PolyHb group revealed a few apoptotic bodies, some acute inflammatory infiltrates in the sinusoids, nuclear fragmentations, cell shrinkage, and chromatin clumping with formation of apoptotic bodies in the apoptotic cells under microscopic examination. Alanine aminotransferase, aspartate aminotransferase, superoxide production, and hydrogen peroxide levels were lower in the PSC than the PolyHb group. Hepatic structures were well preserved in the PSC group. CONCLUSIONS: Reactive oxygen species contribute to hepatic dysfunction with morphologic changes. PSC is effective to reduce hepatic damage by lowering oxygen free radical-mediated injury after ischemia/reperfusion in the liver. 相似文献
79.
Effect of epigallocatechin gallate on renal function in cyclosporine-induced nephrotoxicity 总被引:6,自引:0,他引:6
INTRODUCTION: Nephrotoxicity is a clinically important side effect of cyclosporine (CsA). CsA-induced nephrotoxicity results from increased production of free radical species in the kidney. Epigallocatechin gallate (EGCG) acts as an antioxidant, thus, EGCG may have a protective effect on the alteration of renal function resultant from oxygen free radicals. The purpose of the present study was to investigate the protective effect of EGCG in a rodent model. METHODS: Experiments were performed on 3 groups. The normal control group (group 1) received normal saline solution. The CsA-treated group (group 2; 15 mg/kg body weight/d for 14 days) received subcutaneous injections. The EGCG-treated group (group 3) in addition received 25 mg of EGCG/kg body weight by intraperitoneal injection. RESULTS: There were significant increases in levels of blood urea nitrogen (BUN)(42.8 +/- 8.2 mg/dL; P < .001), serum creatinine (1.18 +/- 0.60 mg/dL; P < .05), and serum malondialdehyde (3.09 +/- 0.20 nmol/mL; P < .001), and a significant decrease in CCr(0.07 +/- 0.02 mL/min; P < .001) in group 2 compared with group 1. Levels of BUN (30.2 +/- 0.7 mg/dL; P < .01)and CCr (0.12 +/- 0.08 mL/min) were lower in group 3 than in group 2. Serum creatinine (0.71 +/- 0.04 mg/dL) and serum malondialdehyde level (2.13 +/- 0.15; P < .001 nmol/mL) were lower in group 3 than in group 2. There was no significant difference in CsA levels between group 2 (6.86 +/- 1.48 mug/mL) and group 3 (6.69 +/- 0.62 mug/mL). CONCLUSIONS: EGCG treatment significantly protected renal function and free radical-mediated injury in the kidney from CsA-induced changes. 相似文献
80.
Fine mapping of the 11q22-23 tumor suppressive region and involvement of TSLC1 in nasopharyngeal carcinoma 总被引:4,自引:0,他引:4
Lung HL Cheng Y Kumaran MK Liu ET Murakami Y Chan CY Yau WL Ko JM Stanbridge EJ Lung ML 《International journal of cancer. Journal international du cancer》2004,112(4):628-635
Previous studies transferring an intact chromosome 11 into HONE1 cells demonstrated the functional significance of chromosome regions, 11q13 and 11q22-23, in nasopharyngeal carcinoma (NPC) development. In our study the 11q22-23 region was comprehensively re-investigated by detailed microsatellite and single nucleotide polymorphism genotyping and by fluorescence in situ hybridization to map precisely the regions containing tumor suppressive activity. We observed 3 chromosomal intervals within 11q22-23 that were commonly lost in the tumor segregants derived from HONE1/chromosome 11 hybrids. One critical region of 0.36 Mb was mapped near the marker D11S2000 and a second 0.44 Mb region was located around the markers D11S1300 and D11S1391. In a third region high allelic loss was also observed at marker D11S4484, where a newly cloned tumor suppressor gene, TSLC1 (tumor suppressor in lung cancer 1), is located. The gene expression analysis showed absence or low expression levels of TSLC1 mRNA in 4 highly tumorigenic NPC cell lines. In addition, the methylation study results show that the TSLC1 promoter region was hypermethylated in all 4 NPC cell lines and re-expression of the gene occurs in HONE1 cells after 5-aza-2'-deoxycytidine treatment. Hence, the mode of silencing of this candidate TSG in NPC may be attributed to promoter hypermethylation. We have obtained functional evidence for multiple critical tumor suppressive regions in 11q22-23 by fine deletion mapping and for inactivation of TSLC1 being one of these candidate TSGs in NPC development. 相似文献