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61.
This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis. 相似文献
62.
Iman Abou-Gareeb Susan Lewallen Ken Bassett Paul Courtright 《Ophthalmic epidemiology》2013,20(1):39-56
BACKGROUND: Many individual surveys of blindness have reported slightly higher rates of blindness for women. In order to gain a continent-by-continent and global sense of the burden of blindness by sex we conducted a meta-analysis of published, population-based surveys of blindness. METHOD: Published reports were collected using a predetermined search protocol involving commercial electronic databases, hand-searching of references and direct contact with researchers. Studies were included that were population-based, included clinical examination and had a minimum sample size of 1000. The studies were critically appraised to determine methodological rigour. Data were analysed using the Cochrane Collaboration Review Manager. RESULTS: The overall odds ratio (age-adjusted) of blind women to men is 1.43 (95% CI 1.33–1.53), ranging from 1.39 (95% CI 1.20–1.61) in Africa, 1.41 (95% CI 1.29–1.54) in Asia, and 1.63 (95% CI 1.30–2.05) in industrialised countries. There was good homogeneity of findings from Africa, Asia, and the industrialised countries. Globally, women bear excess blindness compared to men. In these surveys, overall, women account for 64.5% of all blind people. The excess of blindness in women was marked among the elderly and not due only to differential life expectancy. CONCLUSION: The excess burden of blindness among women is likely due to a number of factors, which are different in industrialised countries compared to developing countries. Particular attention to gender differences in blindness is needed in the creation of targets for blindness reduction and in the development of interventions. 相似文献
63.
64.
Mark D. Markel Mark A. Wikenheiser Richard L. Morin David G. Lewallen Edmund Y. S. Chao 《Calcified tissue international》1991,48(6):392-399
Summary Dual-energy X-ray absorptiometry (DEXA) and single-photon absorptiometry (SPA) were used to quantitate the structural strength
and local material properties of healing tibial osteotomies in 32 dogs. Dogs were divided into four equal groups, euthanatized
at either 2, 4, 8, or 12 weeks, and imaged with DEXA and SPA. Invasive techniques were used to determine (1) the torsional
properties of the bone, (2) the local stiffness properties and calcium content within the bone, and (3) new bone formation
and porosity by histology. There were no differences between SPA and DEXA in their associations with the torsional properties
of bone. SPA and DEXA had strong correlations with the ultimate torque (R2=0.76, 0.51) and the torsional stiffness (R2=0.68, 0.53) of bone. SPA and DEXA of periosteal callus, endosteal callus, and cortical bone had similar associations with
indentation stiffness, calcium content, new bone formation, and porosity. SPA of gap tissue had significantly stronger associations
with these four parameters than DEXA (P<0.05). Correlation coefficients (R2) with these local material properties ranged as high as 0.82 for SPA with new bone formation in the gap tissue and 0.73 for
DEXA with indentation stiffness of periosteal callus. 相似文献
65.
Spondylometaphyseal dysplasia, corner fracture type: a heritable condition associated with coxa vara
Langer LO Jr; Brill PW; Ozonoff MB; Pauli RM; Wilson WG; Alford BA; Pavlov H; Drake DG 《Radiology》1990,175(3):761-766
The authors present the radiographic features of a previously incompletely delineated bone dysplasia, which they call spondylometaphyseal dysplasia, corner fracture type. This is a dominant heritable condition associated with short stature and developmental coxa vara. The progressive hip deformity usually causes significant disability requiring surgical correction. Developmental coxa vara, simulated corner fractures of long tubular bones, and vertebral body abnormalities result in a diagnostic constellation. Knowledge of these distinctive radiologic features allows accurate diagnosis, which in turn should lead to appropriate genetic counseling and possibly to earlier, more efficacious surgical treatment of the coxa vara. 相似文献
66.
67.
JE Barberie DG Connell PL Munk DL Janzen 《Journal of Medical Imaging and Radiation Oncology》1999,43(3):355-357
Muscle and nerve injuries in the hand may be difficult to detect and diagnose clinically. Two cases are reported in which magnetic resonance imaging showed ulnar nerve injury and intrinsic hand muscle denervation. The clinical, anatomical and radiological features of injury to the deep motor branch of the ulnar nerve and associated muscle denervation are discussed and illustrated. 相似文献
68.
A complete gait analysis was performed on six children with below-knee amputations to determine the kinematics and kinetics of amputee gait in children. A relatively new method of analysis--the inverse dynamic relationship--was used to determine the joint moments in the sagittal plane of the joints in the intact limb and the remaining portion of the amputated limb. The joint moments in the sagittal plane of the intact limb in the child amputee were found to be normal or below normal during level walking. From this study, it was concluded that providing a child amputee has a good prosthetic fit, there will be no increased forces across the joints of the intact or amputated limb and consequently no predisposition to premature degenerative arthritis. 相似文献
69.
The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy. 相似文献
70.