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171.
Effect of allogeneic Schwann cell transplantation on peripheral nerve regeneration 总被引:24,自引:0,他引:24
Transplantation of allogeneic Schwann cells (SC) would make it feasible to reconstruct immediately peripheral nerve defects, compared to using autologous SC; however, this treatment modality has not been adequately evaluated. The aim of this study was to characterize and compare the effects of allogeneic versus syngeneic SC transplantation following peripheral nerve injury. Polyhydroxybutyrate conduits were used to bridge a 10-mm gap in the rat sciatic nerve. The conduits were filled with alginate hydrogel with or without cultured allogeneic or syngeneic genetically labeled SC, without the use of immunosuppressive therapy, and examined after 2, 3, and 6 weeks with 5-bromo-4-chloro-3-indoyl-beta-D-galactosidase chemical staining and immunohistochemistry to quantify SC migration into the conduit, axonal regeneration, the state of SC differentiation, and the expression of major histocompatibility complexes (MHC) I and II, as well as to quantify macrophage and B- and T-lymphocyte infiltration. Allogeneic SC were rejected by 6 weeks, whereas syngeneic SC could still be identified. Allogeneic and syngeneic SC equally enhanced the axonal regeneration distance but the quantity of axons was greater using syngeneic SC. The ingrowth of SC into the conduits containing allogeneic SC was similar to that observed in the presence of syngeneic SC, indicating the absence of deleterious immune response. SC continued to express phenotypic markers of nonmyelination and these were highest in conduits with allogeneic SC. Expression of MHC I and II was higher in the conduits with allogeneic SC at 3 weeks and without significant difference in the number of macrophages and lymphocytes, except at 6 weeks, when there was a larger number of lymphocytes using syngeneic SC. In conclusion, allogeneic SC enhanced axonal regeneration distance and did not induce a deleterious immune response. In a clinical setting the immediate availability of allogeneic SC for transplantation may compensate for the better outcome achieved by the use of autologous SC that require a longer preparation time in culture. 相似文献
172.
Event-related potentials (ERPs) and behavioural measures were used to investigate recognition memory and source-monitoring judgements about previously perceived and imagined pictures. At study, word labels of common objects were presented. Half of these were followed by a corresponding picture and the other half by an empty frame, signalling to the participants to mentally visualise an image. At test, participants in a source-monitoring task made a three-way discrimination between new words and words corresponding to previously perceived and imagined pictures. Participants in an old/new-recognition task indicated whether test words were previously presented or not. In both tasks, correctly identified old items elicited more positive-going ERPs than correctly judged new items. This widely distributed old/new effect was found to have an earlier onset and to be of a greater magnitude for imagined than for perceived items. Task (source versus item-memory) affected the old/new effects over prefrontal areas and the reaction times to remembered old items. The present findings are consistent with the view that a greater amount, or a different type, of information is necessary for accurate source-memory judgements than for correct recognition, and moreover, that different types of source-specifying information revive at different rates. In addition, the results add weight to the view that the late widespread ERP-old/new effect is sensitive to the quality or the amount of information retrieved from memory. 相似文献
173.
174.
Antithrombotic effect of tissue factor inhibition by inactivated factor VIIa: an ex vivo human study
Lev EI Marmur JD Zdravkovic M Osende JI Robbins J Delfin JA Richard M Erhardtsen E Thomsen MS Lincoff AM Badimon JJ 《Arteriosclerosis, thrombosis, and vascular biology》2002,22(6):1036-1041
FFR-rFVIIa is an inactivated recombinant factor VIIa (rFVIIa) that inhibits the binding of factor VIIa to tissue factor (TF). It has been shown to prevent TF-induced thrombosis in animals. The present study is a substudy of the Active Site Inhibited Seven (ASIS) trial and examines the antithrombotic effect of 3 doses of FFR-rFVIIa in 24 patients undergoing percutaneous coronary intervention (PCI). Group 1 (n=9) received 400 microg/kg FFR-rFVIIa and 40 to 50 U/kg heparin, group 2 (n=7) received 200 microg/kg FFR-rFVIIa and 100 U/kg heparin, and group 3 (n=8) received 50 microg/kg FFR-rFVIIa and 100 U/kg heparin. Blood thrombogenicity was assessed as total thrombus area and fibrin deposition on the perfusion chamber at shear rate conditions typical of mild-moderate coronary stenosis. Baseline blood thrombogenicity was evaluated a day before PCI, after heparin administration. A second perfusion chamber study was performed just before PCI, 15 minutes after the administration of heparin and FFR-rFVIIa. Thrombus formation at a high shear rate was markedly reduced in groups 1 and 2 after drug administration, by 79% to 84% and 76% to 87%, respectively (P<0.004 [group 1], P<0.04 [group 2]). In group 3, moderate thrombus reduction of 46% to 48% was achieved (P<0.04). Fibrin deposition in all 3 groups was nearly eliminated after drug administration. Our data demonstrate that FFR-rFVIIa has a potent antithrombotic effect at different shear rates and severe arterial injury conditions. 相似文献
175.
BACKGROUND: Thrombolytic therapy results in reperfusion of the occluded coronary vessel in approximately 75% of treated patients with acute myocardial infarction (AMI). Unsuccessful thrombolysis results in impaired outcome. This study was undertaken to evaluate reperfusion assessments with 12-lead standard static electrocardiography (ECG) and continuous vectorcardiography (VCG) in AMI patients treated with thrombolytic therapy, with particular emphasis on the value of these assessments in relation to long-term outcome. METHODS: ST-recovery analysis 90 and 180 min after the start of thrombolytic therapy was performed by repeated ECG and by VCG in 63 AMI patients. Median follow-up was 255 days. RESULTS: No significant differences in long-term outcome were found between patients with or without obtained reperfusion, as assessed by ECG. For VCG, we found significant elevated relative risks for experiencing death (relative risk = 11.00, confidence interval = 2.70-44.90); P = 0.0008 for the group with ST-vector magnitude recovery of less than 50% at 90 min from start of thrombolytic therapy. CONCLUSION: We demonstrated that early reperfusion assessment with VCG enables the prediction of long-term outcome and is superior to reperfusion assessment with standard static ECG in this regard. We therefore recommend continuous ischemia monitoring of AMI patients treated with thrombolytic therapy as a routine procedure. 相似文献
176.
177.
178.
Probiotic effects on faecal inflammatory markers and on faecal IgA in food allergic atopic eczema/dermatitis syndrome infants 总被引:4,自引:0,他引:4
Mirva Viljanen Mikael Kuitunen Tari Haahtela Kaisu Juntunen-Backman Riitta Korpela Erkki Savilahti 《Pediatric allergy and immunology》2005,16(1):65-71
Probiotic bacteria are proposed to alleviate intestinal inflammation in infants with atopic eczema/dermatitis syndrome (AEDS) and food allergy. In such infants we investigated effects of probiotic bacteria on faecal IgA, and on the intestinal inflammation markers tumour necrosis factor-alpha (TNF-alpha), alpha1-antitrypsin (AT), and eosinophil cationic protein (ECP). A total of 230 infants with AEDS and suspected cow's milk allergy (CMA) received in a randomized double-blinded manner, concomitant with elimination diet, Lactobacillus GG (LGG), a mixture of four probiotic strains (MIX), or placebo for 4 wk. Four weeks after treatment, CMA was diagnosed with a double-blind placebo-controlled milk challenge. Faecal samples of 102 infants, randomly chosen for analysis, were collected before treatment, after 4-wk treatment, and on the first day of milk challenge. After treatment, IgA levels tended to be higher in probiotic groups than in the placebo group (LGG vs. placebo, p=0.064; MIX vs. placebo, p=0.064), and AT decreased in the LGG group, but not in other treatment groups. After challenge in IgE-associated CMA infants, faecal IgA was higher for LGG than for placebo (p=0.014), and TNF-alpha was lower for LGG than for placebo, but non-significantly (p=0.111). In conclusion, 4-wk treatment with LGG may alleviate intestinal inflammation in infants with AEDS and CMA. 相似文献
179.
OBJECTIVE: Primary orthostatic tremor is a rare neurologic condition of unknown origin characterized by a 10- to 20-Hz tremor in the legs while standing. Patients with primary orthostatic tremor usually complain of dizziness and unsteadiness that is relieved if they sit down or start to walk around. These patients might be referred to neurotology clinics. Previously, the only way to make the diagnosis has been by means of surface electromyographic recordings from the lower limbs during standing. The authors wanted to study whether posturography can be used to screen for primary orthostatic tremor. STUDY DESIGN: Retrospective case review. SETTING: Balance clinic at a tertiary referral center. PATIENTS: From September 2000 to August 2002, 701 patients were investigated at the authors' balance clinic. INTERVENTION: Static posturography on a force platform with 50-Hz sampling frequency. Recordings were made during 120 seconds of quiescent stance with open or closed eyes. MAIN OUTCOME MEASURE: Fast-Fourier transformation (FFT) analysis of recorded torque in the fore-to-aft direction to quantify the spectral power distribution in the range of 0 to 25 Hz. Visual inspection of power spectrum plots was performed. RESULTS: Five patients (0.7%) were identified (1 man and 4 women; mean age, 56 yr; age range, 36-73 yr) with narrow peaks at 8.5 to 18 Hz in the power spectra of their posturographic recordings. Surface electromyographic recordings during standing confirmed their diagnosis of primary orthostatic tremor. CONCLUSION: Analysis of power spectra from posturographic recordings is a simple, quick method to screen for primary orthostatic tremor. The condition might be more common than previously assumed. It is important to identify patients with primary orthostatic tremor because they might be misdiagnosed and left without treatment. 相似文献
180.
Background: The Swedish adjustable gastric band (SAGB) was introduced in 1985 and rapidly gained popularity.Today more than
21,000 gastric banding procedures have been performed in Europe. The reported results of gastric banding operations are mainly
good, although the method is not without controversies and risks. We report here our initial experience with the SAGB. Methods:
60 patients (44 women, 16 men) were treated surgically for morbid obesity between the years 1996 and 1999, with SAGB. Median
age of the patients was 44 years (range 21-64) and preoperative median Body Mass Index (BMI, kg/m2) was 45 (range 35-55).
3 patients were operated by an open approach, and the remaining 57 laparoscopically. Results:Operative time was 62-206 minutes
(median 97 minutes). Only one operation was converted to open approach (1.8%), due to extensive adhesions. No intraoperative
complications occurred. At 1 year follow-up, mean weight loss was 30 kg, mean excess weight loss was 50%, and median BMI was
35. 4 patients have been reoperated so far (6.7%) due to slippage of the band (2 patients), infection of the band (1 patient),
and leaking of the filling system (1 patient). Median postoperative hospital stay was 3 days (range 2-53). Mortality was 0%.
Immediate postoperative mor- bidity-rate was 12% (7/60), although serious morbidity occurred in only 1 patient (1.7%). Conclusions:
Laparoscopically placed adjustable gastric band is a good option for the morbidly obese patient. 相似文献