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961.
Nir Ofer Solange Akselrod Meir Nyska Miriam Werner Ernesto Glaser Shay Shabat 《Journal of orthopaedic research》2004,22(6):1296-1302
Degenerative or pre-degenerative processes in the tendon, which could lead to a spontaneous rupture, are well known problems, especially among athletes. Existing non-invasive diagnostic methods are mainly based on subjective analysis of static images of the tendon, but in many cases the degeneration cannot be diagnosed in time. Combining a set of existing image processing techniques, a tool for tracking the in vivo motion of a tendon imaged with dynamic ultrasound was implemented. A group of subjects that had undergone a degenerative rupture of their Achilles tendon, one subject with a traumatic rupture, and a group of control subjects were all tested. Using the motion information that was obtained from both tendons of all subjects, we developed an automatic test that examines the symmetrical properties of the tendon's motion, and defined a negative asymmetry property that could be quantified as a score. This score was found to be significantly more enhanced in the post-operative tendons (18.0 +/- 9.0) than in the contra-lateral healthy tendons of the same subjects (3.9 +/- 4.6). In the single traumatic rupture subject, this effect was not found (0.0). This leads us to believe that the negative asymmetry of tendon motion may be associated with degenerative or pre-degenerative processes in the tendon. Also, the mean degree of negative asymmetry in the healthy tendons of post-operative subjects (3.9 +/- 4.6) was found to be higher than that of healthy tendons of the control group (1.5 +/- 1.8). This finding may be associated with the fact that tendons that are contra-lateral to spontaneously ruptured tendons have a higher risk of developing degenerative processes. The method presented here is objective, low-cost, non-invasive and possibly more sensitive than existing non-invasive techniques. 相似文献
962.
963.
964.
965.
High rates and the risk factors for emergency room visits and hospitalization in Parkinson's disease
Anhar Hassan Samuel S. Wu Peter Schmidt Yunfeng Dai Tanya Simuni Nir Giladi Bastiaan R. Bloem Irene A. Malaty Michael S. Okun 《Parkinsonism & related disorders》2013,19(11):949-954
BackgroundParkinson's disease (PD) patients are hospitalized more frequently than their peers as a result of falls, psychosis, infections and other medical complications. However, patient-specific risk factors for hospitalization are unclear.ObjectiveTo identify rates and risk factors for hospital encounters (Emergency Room [ER] visits or hospitalization) among people with PD.Methods3415 PD participants (mean age 67 ± 10 years, disease duration 9 ± 6 years, H&Y 2 47%, H&Y 3 26%) enrolled in the prospective international multicenter NPF-QII Study. One-year follow-up data was available for 1030 patients. Rates and risk factors for hospital encounters were determined at baseline and after one year follow-up.ResultsOf 3415 PD participants at study entry, 1120 (33%) reported at least one hospital encounter. Associations were: longer timed up-and-go test (OR: 1.33), increased comorbidities (OR: 1.25), motor fluctuations (OR: 1.32), and deep brain stimulation (DBS) (OR: 2.49). Of these 1120 persons, 311 had follow-up data and 158 (51%) had a repeat encounter one year later, associated with higher H&Y stage, fluctuations, and lower health-related quality-of-life. Of 2295 participants without a hospital encounter at baseline, 719 had follow-up data and 178 (25%) had a first hospital encounter one year later. Risk factors were female gender, comorbidities, lower cognition, fluctuations, and DBS.ConclusionsOne-third of people with PD had a hospital encounter each year, and one-half of those had a repeat encounter. These high rates correlated with disease severity, comorbidities and DBS. There is an urgent need to develop programs to reduce PD hospital encounters. 相似文献
966.
Background
In the prelaparoscopy era, macroscopically normal appendices were routinely resected. The aim of this study was to evaluate the accuracy of laparoscopy.Methods
A review of 1,899 patients who underwent appendectomy with multivariate analysis was conducted.Results
Laparoscopic and open approaches had similar false-positive rates, false-negative rates, accuracy, and sensitivity. The study population included 17 false-negative cases (11% of all macroscopically normal appendices). Tumors were found in 1.1% of our study population. Female gender (1.9% vs .5%; odds ratio, 4; 95% confidence interval, 1.5 to 11; P < .005) and appendiceal perforation were independent risk factors for harboring a tumor.Conclusions
It is suggested that laparoscopy has diagnostic quality similar to that of the open approach. Until randomized trials evaluate the fate of patients who receive false-negative diagnoses, routine appendectomy is recommended. Special attention should be paid to female patients and to patients with perforations, who have a 4-fold increased risk for harboring a tumor. 相似文献967.
968.
Eran Hadar Nir Melamed Keren Tzadikevitch-Geffen Yariv Yogev 《Archives of gynecology and obstetrics》2011,283(4):735-741
Objective
To investigate the timing and risk factors of maternal complications of cesarean section (CS). 相似文献969.
Nir Hilzenrat Arie Arish§ Arieh Yaari Emanuel Sikuler 《Journal of gastroenterology and hepatology》2001,16(7):796-800
BACKGROUND AND AIMS: Recently, we found in a portal hypertensive rat model that hemorrhage and volume restitution with Haemaccel, a low viscosity plasma expander, induced an increase in cardiac output and portal venous inflow. The present study was conducted to evaluate whether pretreatment with propranolol will attenuate these hyperdynamic changes. METHODS: Portal hypertension was induced by portal vein constriction. Treatment was initiated 14--21 days later. Propranolol (30 mg/kg per day) or water were administered for 7 days via a gastric gavage. Under ketamine anesthesia, 18 h after the last given dose, blood was withdrawn at a constant rate of 0.3 mL/min for 15 min followed by a 15-min stabilization. Haemaccel was infused at the same rate and volume used for withdrawal. Hemodynamic measurements were performed after volume restitution in both groups by using radioactive microspheres. RESULTS: Eight rats were studied in each group. In the propranolol-treated animals, portal venous inflow was decreased (2.4 +/- 0.8 vs 3.8 +/- 0.7 mL/min per 100 g bodyweight; P < 0.01), while splanchnic arteriolar and porto-collateral resistance were increased (52.8 +/- 21.0 vs 32.8 +/- 13.0 and 6.0 +/- 1.4 vs 4.1 +/- 0.7 mmHg x min x 100 g bodyweight/mL; P < 0.05, respectively). Cardiac output, mean arterial pressure, heart rate, total peripheral resistance and portal pressure were not significantly different between the two groups. CONCLUSION: In this model, pretreatment with propranolol prevented the increase in portal venous inflow, which occurs following hemorrhage and volume restitution with Haemaccel. Although caution should be taken in extrapolating data from animal models to humans, our results suggest that volume replacement during a portal hypertensive-related bleeding episode may be safer in a patient treated with non-selective beta-adrenoreceptor antagonists. 相似文献
970.
Galit Yogev‐Seligmann MscPT Jeffrey M. Hausdorff PhD Nir Giladi MD 《Movement disorders》2008,23(3):329-342
Until recently, gait was generally viewed as a largely automated motor task, requiring minimal higher‐level cognitive input. Increasing evidence, however, links alterations in executive function and attention to gait disturbances. This review discusses the role of executive function and attention in healthy walking and gait disorders while summarizing the relevant, recent literature. We describe the variety of gait disorders that may be associated with different aspects of executive function, and discuss the changes occurring in executive function as a result of aging and disease as well the potential impact of these changes on gait. The attentional demands of gait are often tested using dual tasking methodologies. Relevant studies in healthy adults and patients are presented, as are the possible mechanisms responsible for the deterioration of gait during dual tasking. Lastly, we suggest how assessments of executive function and attention could be applied in the clinical setting as part of the process of identifying and understanding gait disorders and fall risk. © 2007 Movement Disorder Society 相似文献