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101.
Ayala Espinosa MJ Pérez-Santonja JJ Alió Y Sanz JL Artola Roig A Cardona Ausina C 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(12):835-837
CASE REPORT: We present a case of traumatic displacement of corneal flap in the superior temporal quadrant 13 days after LASIK. The flap was repositioned after gentle irrigation of BSS, cleaned the interface and then drying the flap to verify its stability. In the next day the flap was adhered, clear cornea,smooth and visual acuity without correction was 1.00. DISCUSSION: We should try immediately to reposition the flap after traumatic displacement, as in this case. 相似文献
102.
G Noack P Berggren T Curstedt G Grossmann P Herin W Mortensson R Nilsson B Robertson 《Acta paediatrica Scandinavica》1987,76(5):697-705
Ten newborn infants (795-1680 g) with severe respiratory distress syndrome (RDS) were treated with the isolated phospholipid fraction of bovine or porcine surfactant, which was administered via the airways (dose 200 mg/kg), at a median age of 10.5 h. Before receiving surfactant, all the infants were on artificial ventilation (FiO2 0.6-1.0). Within 2 h after surfactant replacement, the arterial-to-alveolar PO2 ratio increased from 0.1 to 0.35. There was a concomitant improvement in lung aeration on the chest roentgenograms and a significant reduction in the right-to-left shunt. Four patients died of cerebral hemorrhage; two of them also had a patent ductus arteriosus. One surviving infant developed bronchopulmonary dysplasia, and another succumbed 8 months later to the sudden infant death syndrome. No antibodies against surfactant were detected in the sera of the survivors. Since our results show a significant improvement in lung function after replacement therapy, the efficacy of this new surfactant preparation should be further tested in randomized clinical trials. 相似文献
103.
OBJECTIVES: Cavity lining with flowable composites has been proposed to reduce interfacial stress due to its strain-absorbing capacity. The purpose of this in vitro study was to evaluate marginal and internal adaptation of large Class I restorations filled in bulk after cavity lining with flowable composites. METHODS: Forty standardised large Class I cavities with enamel margins not supported by dentin, were randomly assigned to four groups and either restored in bulk after lining with flowable composites or in two oblique layers of high-viscosity composites. Two adhesives and flowable resins were used: Tetric Ceram, Tetric Flow, Excite (Vivadent, Schaan, Liechtenstein) vs. Prodigy Condensable, Revolution, Optibond Solo (Kerr Co., Orange, CA, USA). Immediately after restorative procedure marginal quality and the internal restoration interface of two bucco-oral sections were quantitatively assessed by SEM using replica technique. RESULTS: Marginal gaps were almost not seen in all test groups (<0.001%), whereas marginal enamel fractures frequently occurred (>23%). No differences in marginal adaptation were detected for both application techniques if the same adhesive was used (ANOVA, Tukey, p<0.05). Lining with Revolution resulted in a significantly higher percentage of marginal continuity (MC) and less enamel fractures (EF) compared to Tetric Flow (MC: 73 vs. 45%; EF: 23 vs. 50%). Gaps at the inner interface were rarely observed (<0.05%). CONCLUSIONS: Large Class I restorations without dentin supported cavity margins showed a high amount of marginal enamel fractures directly after placement. Lining with Revolution proved to have the highest potential to initially maintain the marginal integrity. 相似文献
104.
105.
MJ Veness F Foroudi V Gebski I Timms Y Sathiyaseelan B Cakir KW Tiver 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):468-474
Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E1 analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis. 相似文献
106.
GM Thambugala A Mohamed GFA O Neill MJ Fulham 《Journal of Medical Imaging and Radiation Oncology》2006,50(6):604-606
We present the FDG PET‐CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para‐aortic nodes, a PET‐CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET‐CT findings in sarcomatoid renal cell carcinomas. 相似文献
107.
A role for free radicals has been proposed in infectious brain disease, where resident microglia cells upregulate the inducible nitric oxide synthase isoform (iNOS), and thus are capable of producing nitric oxide at enhanced rates. Using the constitutively expressed NADPH oxidase, microglial cells can generate superoxide, which reacts with nitric oxide to form the powerful oxidant peroxynitrite. In a mixed cell culture system of astrocytes and microglial cells, nitrite levels, used as an indicator of nitric oxide production, were elevated after the addition of lipopolysaccharide (LPS) and cytokines. Immunohistochemistry and the NADPH diaphorase technique demonstrated selective localization of the iNOS protein in microglial cells, whereas no iNOS protein or NADPH diaphorase activity was detected in astrocytes. A similar cellular distribution was observed in vivo following injection of LPS and cytokines into the rat striatum. By contrast, LPS and interferon-gamma led to translocation of NF-kappaB in microglia and in astrocytes, demonstrating that both cell types are responsive to the stimulus. Therefore, downstream control in iNOS expression is cell type-specific. 相似文献
108.
Modification of oral mucositis by keratinocyte growth factor: single radiation exposure 总被引:7,自引:0,他引:7
PURPOSE: The aim was to quantify the effect of recombinant human keratinocyte growth factor (rhKGF) on acute oral mucositis induced by a single radiation dose, simulating accidental radiation exposure. MATERIAL AND METHODS: Tongue epithelium of the C3H/Neu mouse was irradiated with graded single doses of 25 kV X-rays to a 3 x 3 mm2 area in the centre of the lower tongue surface. Acute mucosal ulceration, as a clinically relevant reaction, was used as the quantal endpoint for dose response analyses by probit analysis. As a secondary endpoint the time-course, i.e. time to first diagnosis of ulcer (latent time) and individual ulcer duration, was analysed. KGF was applied before, after or in combination before and after radiation exposure. RESULTS: Administration of KGF in all protocols resulted in a significant reduction of the incidence of oral mucosal ulceration, as illustrated by an increase in iso-effective dose from 10.9 to 24.9 Gy; the corresponding dose-modification factors ranged between 1.7 and 2.3. The effect was most pronounced when KGF was applied after irradiation. In all protocols where KGF was given after irradiation, a significant shortening of the latent time to ulceration from 11 to 6-8 days was observed. CONCLUSIONS: The mechanisms underlying the amelioration of the oral mucosal response to single-dose irradiation remain unclear. However, KGF represents a promising approach for the effective management of acute radiation reactions in oral, gastrointestinal and cutaneous epithelia after radiation exposure. 相似文献
109.
Comparison of quality of life in patients undergoing abdominoperineal extirpation or anterior resection for rectal cancer 总被引:18,自引:0,他引:18 下载免费PDF全文
OBJECTIVE: To evaluate the quality of life (QoL) in patients undergoing anterior resection (AR) or abdominoperineal extirpation (APE) for rectal cancer in a sample of patients recruited from a field trial. SUMMARY BACKGROUND DATA: Abdominoperineal resection has been reported to put patients at higher risk of disruption to QoL than sphincter-preserving surgery. METHODS: Fifty patients treated with AR and 23 patients treated with APE were prospectively followed up. All patients were treated in curative attempt and were disease-free throughout the study. QoL was assessed before surgery and 6 to 9 and 12 to 15 months after surgery. RESULTS: Multivariate analysis of variance and subsequent post hoc comparisons revealed a main effect for time (role function, emotional function, body image, future perspective, and micturition-related problems) and group in favor of APE (sleeping problems, constipation, diarrhea), and a time-by-group interaction (role function). No significant results were obtained for the remaining scores, but patients undergoing APE consistently had more favorable QoL scores than those undergoing AR. Multivariate analysis and post hoc comparisons revealed a particularly poor QoL for patients undergoing low AR. They had a significantly lower total QoL, role function, social function, body image, and future perspective, and more gastrointestinal and defecation-related symptoms than patients undergoing high AR. CONCLUSION: Patients undergoing APE do not have a poorer QoL than patients undergoing AR. Patients undergoing low AR have a lower QoL than those undergoing APE. Attention should be paid to QoL concerns expressed by patients undergoing low AR. 相似文献
110.
Does chemomechanical caries removal affect dentine adhesion? 总被引:2,自引:0,他引:2
The purpose of this study was to determine whether shear bond strengths (SBS) to chemomechanically excavated dentine (Carisolv) differed from the SBS after conventional caries removal (bur). The following adhesive systems were used: Dyract AP/NRC/Prime & Bond NT; Dyract AP/Prime & Bond NT; Tetric Ceram/ Syntac SC; Tetric Ceram/Syntac SC (no etch) (TC 2); Definite/Etch & Prime 3.0; Definite/experimental. One-hundred and twenty human molars with occlusal caries were assigned to 12 groups. Sequential caries removal was controlled with laser fluorescence. After water storage, the samples were tested in a single-plane shear test assembly. The results demonstrated differences between the bonding systems, whereas the mode of caries removal had no consistent effect. If total etch technique was neglected, the results of the composite resin (TC 2) indicated a tendency to higher SBS in the Carisolv group (18.6 +/- 4.6 MPa) compared with conventional treatment (14.1 +/- 3.9 MPa). The present data demonstrate that chemomechanical caries removal has no adverse effect on bonding of modern adhesive systems to dentine. Smear layer-dissolving or -modifying bonding systems could potentially benefit from chemomechanical pretreatment. 相似文献