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61.
Children's anticipatory attributional assessment of the source(s) of perceived control is hypothesized to play an important role in the etiology of distress in children undergoing invasive medical procedures. Four perceived control types, based on learned helplessness theory, are specified by a conceptual model that guides this research: Mutual, Powerful Other, Personal, and Unknown. Among 73 children between the ages of 4 and 18 having their blood drawn, it was predicted that children with an attributional analysis of unknown perceived source of control prior to the impending medical procedures would experience a heightened level of anxiety (procedure-related distress). As predicted, children with an anticipatory attributional assessment of unknown perceived control interfered with or extended the medical procedure significantly more (41%) than children who could attribute some perceived source of control (13%). They were also rated by themselves, the parents, and a trained clinical observer as manifesting significantly greater (p < .05) anticipatory procedural distress using both cognitive (subjective) and behavioral (objective) assessment perspectives. These findings were independent of children's age. This paper supports the need for additional theory-driven research and the importance of investigating the role of attributional variables in the etiology of procedure-related distress in children.  相似文献   
62.
We report on 4 generations in a family with 3 living males, 3 males who died in infancy, and 3 females with neurologic impairment and agenesis of the corpus callosum (ACC). Manifestations in the surviving males include severe acquired micrencephaly, mental retardation, limb contractures, scoliosis, tapered digits with hyperconvex nails, a characteristic face with large eyes, prominent supraorbital ridges, synophris, optic atrophy, broad alveolar ridges and seizures. Urologic anomalies include renal dysplasia, cryptorchidism, and hypospadias. Two affected females were less severely impaired and continued to be socially responsive as adults, but had spastic quadriplegia and seizures. One obligate heterozygote was retarded with emotional problems while another obligate carrier female and her daughter were clinically normal. Pedigree analysis suggested X-linked inheritance with variable expression in females. These findings are inconsistent with the well-described X-linked conditions with ACC including FG syndrome and Aicairdi syndrome. ACC has not been described in Coffin-Lowry syndrome, a condition with similar clinical findings, which also demonstrates marked variability of expression in carrier females. In order to assist in carrier determination, brain imaging studies and DNA linkage analysis of the affected relatives was performed. We found a spectrum of agenesis of the corpus callosum with the most severe manifestations in the most severely affected males. DNA analysis using a series of X-linked probes suggests linkage with a LOD score of 1.26 at theta = 0 to a region between p 11.3 and p 21.3.  相似文献   
63.
Aneurysm of the mitral valve in a patient with hypertrophic cardiomyopathy   总被引:2,自引:0,他引:2  
We report a case of mitral valve aneurysm and severe mitral regurgitation complicating infective endocarditis in a patient with hypertrophic cardiomyopathy. 2-dimensional echocardiography revealed a saccular structure in the anterior mitral leaflet that bulged into the left atrium throughout the cardiac cycle. Pathology of the excised valve showed inflammation, early repair and perforation of the aneurysm. Concurrent mitral insufficiency or trauma resulting from septal-anterior mitral leaflet contact may predispose to valvular infection. The repair process of this damaged focus and the loss of the elastic properties of the valve may contribute to aneurysm formation. The aneurysm in this case formed in less than 5 weeks.  相似文献   
64.
We report on two sib fetuses with similar abnormalities detected prenatally by ultrasound. The first fetus had micrognathia, was without cleft palate, and had low-set ears, double outlet right ventricle with a ventricular septal defect, and 46,XY gonadal dysgenesis. The second sib fetus was born with cleft lip and palate, micrognathia, transposition of the great vessels, ventricular septal defect, a right-sided aorta arch, and bilateral cystic kidneys with hypospadias. We were able to identify 11 additional cases in the literature with similar findings. We think this set of defects is a recognizable syndrome that appears to be inherited either as an autosomal recessive or as an X-linked recessive and may overlap with the Smith-Lemli-Opitz syndrome.  相似文献   
65.
66.
Summary Studies have been performed on the afferent fibers innervating the scrotal skin of the rat to test the hypothesis that the generator potential mechanism underlying cold thermosensitivity of these afferent fibers is an electrogenic sodium pump. In these experiments a pudendal nerve-scrotal skin preparation was isolated from the animal and, maintained in oxygenated mammalian Ringer's where composition could be varied and drugs added. Application of ouabain resulted in an increase in the discharge of cold sensitive afferent fibers which was more pronounced at 38–41° C than at temperatures below 30° C. In most of the cases transient accelerations on cooling were reduced, but often a transient response to warming appeared. The effects of ouabain administration were reversible. Removal of extracellular K at 35° C resulted in an increased discharge of cold sensitive afferents. This observation is consistent with the effects of ouabain, since removal of extracellular K also blocks Na transport. The generator potential mechanism underlying cold sensitivity of these afferent fibers appears to be an electrogenic Na pump.  相似文献   
67.
Listener accuracy in identifying voiced and voiceless stops and fricatives in tracheoesophageal (TE) and laryngeal speech were compared. Sixteen TE and ten laryngeal speakers produced ten phonemes embedded in a nonsense word in a carrier phrase. Four experienced listeners phonetically transcribed the experimental phonemes. As expected, perceptual error rates were higher for the TE samples for all comparisons completed. The dominant error for laryngeal samples was a misperception of manner of production. The dominant error for TE samples was a perception of voiced for voiceless phonemes. Such voicing misperceptions occurred more frequently for fricatives than stops. Previous studies have implicated the vibratory characteristics of the pharyngoesophageal (PE) segment for the voicing errors in TE speech. However, PE features would not fully explain why stops were less affected than fricatives and why the expected error was reversed for two TE phonemes (perceptions of voiceless for voiced consonants). LEARNING OUTCOMES: (1) As a result of this activity, the participant will be able to identify the most common listener misperceptions of tracheoesophageal speech. (2) As a result of this activity, the participant will be able to discuss possible reasons for the predominant error that occurs.  相似文献   
68.
There are many steps between drug discovery and prescribing for a patient. Each step has problems. In this issue of ARCHIVES, Klein and colleagues propose changes in clinical trials that would result in more meaningful information for the treating physician. Of particular importance is the gap between what a physician needs to know and what is produced in the clinical trials that leads to approval of a new drug by the US Food and Drug Administration (FDA). Their recommendations for improving clinical trials are cogent, but broad-based implementation depends on an organizational structure and political effectiveness not presently in place. Most important, as the authors note, is an effective work group representing industry, regulatory agencies, and academic and federal science, addressing clinical trials issues with public participation. While improved quality and relevance of data from clinical trials will strengthen the scientific foundation of pharmacotherapy, other problems impede the delivery of objective information to the treating physician. Most hotly debated is the role of money in the creation and dissemination of knowledge.  相似文献   
69.
70.
Splenectomy for hematologic disease   总被引:2,自引:0,他引:2  
One hundred and thirty splenectomies were performed at the University Hospital in Birmingham for hematologic disorders during a 12 year period. There were seven deaths of which four were related to sepsis in patients with malignant growths which probably impaired immune competence. Splenectomy was found to be uniformly satisfactory for hereditary hemolytic anemia, for hypersplenism complicating rheumatoid arthritis and for the rare instance of primary hypersplenism. Splenectomy was usually salutary in didopathic thrombocytopenic purpura and in antoimmune hemolytic anemia. When done for diagnosis, splenectomy was definitive in about 50 per cent of the instances. Individual patients with thrombotic thrombocyeosinophilia syndrome benefited. Splenectomy for hypoplastic or aplastic anemia in an actual circulation offered only questionable benefit and is rarely necessary for hyperplenism secondary to portal hypertension.  相似文献   
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