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排序方式: 共有9305条查询结果,搜索用时 15 毫秒
11.
J W Shore C T Westfall C R Leone R K Newman F W Shagets 《Ophthalmic plastic and reconstructive surgery》1987,3(1):13-15
A 38-year-old man presented with hyperophthalmia, enophthalmos, and upper eyelid retraction 18 months following an osteoplastic flap and frontal sinus obliteration for mucocele. Computerized tomography confirmed the presence of frontal bone absorption in the roof of the orbit with traction and elevation of the orbital contents into the obliterated frontal sinus. A fracture of the orbital roof with penetration of periorbita at the time of original surgery was the suspected precipitating cause of the complication. Surgical management included lysis of the cicatrix between the orbit and frontal sinus and interposition of a silicone sheet between the orbit and sinus, which restored the appropriate anatomic relationships and prevented recurrence. 相似文献
12.
The effect of light intensity on double bond conversion and flexural strength of a model, unfilled dental resin. 总被引:4,自引:0,他引:4
Lale G Lovell Sheldon M Newman Matthew M Donaldson Christopher N Bowman 《Dental materials》2003,19(6):458-465
OBJECTIVE: Two visible light sources (tungsten-quartz-halogen and xenon-arc plasma) with vastly different intensities (200 and 1800 mW/cm(2)) but similar spectral outputs, were used to examine the effects of light intensity on conversion and flexural strength of a model dental resin formulation (75/25wt% bis-GMA/TEGDMA). METHODS: The exact same polymer samples were used to correlate double bond conversion (measured with near-IR spectroscopy) to flexural strength, both immediately after light exposure and after storage. RESULTS: In general, polymers which were irradiated with the high light intensity source exhibited greater double bond conversion. However, increasing the light intensity also increased the maximum temperature reached during polymerization. Therefore, the greater double bond conversion was caused by a combination of both photo and thermal effects. Regardless of the light intensity, a single linear relationship existed between conversion and final flexural strength (measured 4 days after cure) over the conversion range analyzed (50-80%). However, deviations from linearity were noted in several samples that were tested immediately after exposure. SIGNIFICANCE: These findings illustrate that light intensity does not affect the final flexural strength of a dental resin as long as the final conversions are similar. 相似文献
13.
B. Shen MD Z. Younossi MD B. Dolmatch MD J. Newman MD M. Henderson MD J. Ong MD T. Gramlich MD M. Yamani MD 《The American journal of gastroenterology》2000,95(9):2607-2607
14.
Thoracic trauma in children: an indicator of increased mortality 总被引:2,自引:0,他引:2
M H Peclet K D Newman M R Eichelberger C S Gotschall V F Garcia L M Bowman 《Journal of pediatric surgery》1990,25(9):961-5; discussion 965-6
This study was undertaken to assess the significance of thoracic trauma as a marker of morbidity and mortality in children. During a 34-month period, 2,086 children younger than 15 years old were consecutively admitted to a Level I pediatric trauma center with blunt or penetrating trauma. For each child we prospectively recorded Trauma Score (TS), Injury Severity Score, (ISS), medical, and etiologic data. One hundred four children (4.4%) presented with thoracic trauma. The most common mechanisms of injury were pedestrian injury (36%), motor vehicle crashes (32%), and armed assault (12%). The most common injuries were pulmonary contusion (48%), pneumothorax, hemothorax, or pneumohemothorax (39%), and rib fractures (32%). Multisystem injury was present in 82% of the children. The mean TS and ISS were 11 and 27, respectively, significantly worse than scores for children without thoracic injury (15 and 7; P less than .0001). Seventy-one percent of the children were admitted to the intensive care unit, where they stayed an average of 6 days; 20% required surgery. The mortality rate was 26%. Injuries to the heart or great vessels had the highest mortality rate (75%), followed by hemothorax (53%), lung laceration (43%), and rib fracture (42%). Mortality for children with isolated chest injury was 5%, compared with rates of 20% for abdominal and chest trauma, 35% for head and chest trauma, and 39% for trauma to the head, chest, and abdomen. Less than 5% of the admissions to a pediatric trauma center incurred thoracic injury.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
15.
Pantin Hilda Coatsworth J. Douglas Feaster Daniel J. Newman Frederick L. Briones Ervin Prado Guillermo Schwartz Seth J. Szapocznik José 《Prevention science》2003,4(3):189-201
This paper reports a test of the efficacy of Familias Unidas, a Hispanic-specific, ecologically focused, parent-centered preventive intervention, in promoting protection against and reducing risk for adolescent behavior problems. Specifically, the intervention was designed to foster parental investment, reduce adolescent behavior problems, and promote adolescent school bonding/academic achievement, all protective factors against drug abuse and delinquency. One-hundred sixty seven Hispanic families of 6th and 7th grade students from three South Florida public schools were stratified by grade within school and randomly assigned to intervention and no-intervention control conditions. Results indicated that Familias Unidas was efficacious in increasing parental investment and decreasing adolescent behavior problems, but that it did not significantly impact adolescent school bonding/academic achievement. Summer-vacation rates of adolescent behavior problems were six times higher in the control condition than in the intervention condition. Furthermore, change in parental investment during the intervention was predictive of subsequent levels of adolescent behavior problems. The findings suggest that Familias Unidas is efficacious in promoting protection and reducing risk for adolescent problem behaviors in poor immigrant Hispanic families. 相似文献
16.
Summary Meiotic progeny of Chlamydomonas reinhardtii normally receive chloroplast genomes only from the mt
+ parent. However, exceptional zygotes, which transmit the chloroplast genomes of both parents or, more rarely, only those of the mt
- parent, arise at a low frequency. Mutations at the mt
+-linked mat-3 locus were found previously to elevate the transmission of chloroplast genomes from the mt-parent, resulting in a much higher than normal frequency of exceptional zygotes. In this paper we demonstrate that an ultraviolet-sensitive nuclear mutation mapping at the uvsE1 locus, which is unlinked to mating type, also promotes chloroplast genome transmission from the mt
- parent. This mutant, which was previously shown to reduce recombination of nuclear genes in meiosis, acts synergistically which the mat3-3 mutation to produce an extremely high frequency of exceptional zygotes. Through the use of restriction fragment length polymorphisms existing in the chloroplast genomes of C. reinhardtii and the interfertile strain C. smithii, we show that chloroplast DNA fragments from the mt
- parent normally begin to disappear shortly after zygote formation. However, this process appears to be blocked totally in the absence of wild-type uvsE1 and mat-3 gene products. Our findings are consistent with the hypothesis that both gene products contribute to the mechanism responsible for uniparental inheritance of the chloroplast genome from the mt
+ parent. 相似文献
17.
J. T. McCloskey M. C. Newman 《Archives of environmental contamination and toxicology》1995,28(2):195-202
Sediment preference experiments were performed with the asiatic clam (Corbicula fluminea) and viviparid snail (Campeloma decisum) to determine the potential use of clam and snail behavior as a response to low-level metal and metalloid contamination. Three sediment types with varying levels of metal contamination were paired in various combinations. Clams and snails were placed in aquaria along the interface between the sediment types. Daily location and burial status were noted for two weeks. Clams spent significantly more days in the uncontaminated sediment when paired with one of the contaminated sediments. Snails spent more days in contaminated sediments when paired with the uncontaminated sediment, but none of these differences was statistically significant. Clams moved fewer days in tanks with the two most contaminated sediment types. Burrowing of snails was relatively unaffected by sediment treatments. The behavior of clams was more sensitive than the behavior of snails to sediment metal contamination. Consequently, clam behavior appears to be a better behavioral indicator of metal contamination.This work was performed under the auspices of the U.S. Department of Energy. 相似文献
18.
Pathologic features of cytomegalovirus retinopathy after treatment with the antiviral agent ganciclovir 总被引:2,自引:0,他引:2
J S Pepose C Newman M C Bach T C Quinn R F Ambinder G N Holland P S Hodstrom H M Frey R Y Foos 《Ophthalmology》1987,94(4):414-424
Ganciclovir is a new antiviral compound (also called BW B759U, DHPG, BIOLF-62, and 2'NDG) that has been used for the treatment of cytomegalovirus (CMV) retinopathy in immunocompromised patients (bone marrow recipients or acquired immune deficiency syndrome [AIDS] victims). The authors studied the eyes of three AIDS patients with CMV retinopathy who died while receiving ganciclovir chemotherapy. Gross, microscopic, and ultrastructural studies of these cases showed varying degrees of retinal scarring and active CMV lesions at the margins of the scars. CMV antigens were localized in cells at all layers of retina at the border of the lesions and in isolated cells in a perivascular location within histologically normal appearing retina. These areas probably represent sites of recrudescence when the drug is discontinued. In situ hybridization using a cloned complementary DNA (cDNA) probe of human CMV corroborated the immunocytologic localization of the virus. Ultrastructural studies showed megalic syncytial cells containing mostly capsids exclusively in the cell nucleus. The cytoplasmic electron-dense membrane-bound bodies that have characterized untreated cases of CMV retinopathy were absent in the treated cases. An attempt to isolate CMV in tissue culture from the vitreous and retina of one of the cases yielded a negative result. Our results indicate that ganciclovir does not effectively eliminate CMV from the retina nor does it suppress expression of all viral genes. Ganciclovir appears to function by limiting viral DNA synthesis and subsequent packaging of viral DNA into infectious units, thereby acting as a virostatic chemotherapeutic agent. 相似文献
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