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561.
Infection with human immunodeficiency virus (HIV)-1 can lead to neurological complications that range from mild cognitive and motor impairment to HIV-associated dementia (HAD). The mechanism of brain injury and dementia remains poorly understood. Interestingly, post mortem brain specimen from HAD patients and transgenic mice expressing the viral envelope protein gp120 present with similar neuropathological signs. The cytokine erythropoietin (EPO) is clinically used to treat anemia but has also been found to prevent neuronal death due to inflammation or excitotoxicity. Here we show that EPO protects cerebrocortical neurons against apoptosis induced by HIV-1/gp120. 相似文献
562.
The aim of this pilot study was to investigate the secretion rate from minor salivary glands in 16 patients (mean age 62 years) with myeloma, lymphoma or other malignant haematological diseases receiving chemotherapy (study group). An age- and sex-matched control group (n = 16) was recruited. The secretion rate from the minor salivary glands on the inside of the lower lip, measured using the Periotron method, was in mean 2.8 microliters/cm2/min in the study group compared with 4.5 microliters/cm2/min in the control group (p < 0.01). No difference was found in the secretion rate of paraffin-stimulated whole saliva. There were more individuals who experienced dry mouth in the study group (n = 7) than in the control group (n = 2). The conclusion from this pilot study is that the secretion rate from the minor salivary glands might be reduced in cancer patients treated with chemotherapy. 相似文献
563.
Vannier MW; Hildebolt CF; Marsh JL; Pilgram TK; McAlister WH; Shackelford GD; Offutt CJ; Knapp RH 《Radiology》1989,173(3):669-673
Three-dimensional computed tomography (CT) has an important role in determining the presence and extent of congenital and acquired craniofacial deformities. The authors compared the sensitivity and specificity of three-dimensional CT in the detection and characterization of craniosynostosis with that of planar CT and skull radiography. Eighty-two patients with isolated and syndromal synostoses were imaged with CT and three-dimensional CT, and 42 with skull radiography. Three-dimensional CT scan processing was performed by shaded-surface reconstruction, volumetric, and depth-coded methods. Two trained observers read each scan series in a blinded fashion. Diagnostic utility of the images was determined with receiver operating characteristic analysis. The observers ranked three-dimensional shaded images higher than the other types, with three-dimensional volumetric images second and three-dimensional surface images ranked third. Results of this study demonstrate that three-dimensional shaded-surface reconstruction from CT scans is superior to conventional plain radiographs and CT scans in diagnosing craniosynostosis. 相似文献
564.
Jonathan Benjamin RH Belmaker Yuli Berzovsky Arsen Revasov Ora Kofman 《Basic & clinical pharmacology & toxicology》1992,71(Z1):18-25
Lithium powerfully augments the effects of imipramine in resistant depression. We treated four groups of rats for five weeks with (1) saline alone, (2) saline followed by lithium, (3) imipramine alone, and (4) imipramine followed by lithium. There was no augmentation of activity by lithium. Normal human volunteers took imipramine 75 mg daily for three weeks, followed by imipramine 75 mg daily together with lithium 900 mg daily for another ten days. There was no elevation of mood after the addition of lithium. Lithium augmentation of antidepressants apparently requires a pre-existing neurochemical-behavioral disturbance. 相似文献
565.
Birgitta Sundin Lars Granath Dowen Birkhed 《Community dentistry and oral epidemiology》1992,20(2):76-80
The aim of this study was to analyze the relationships between caries incidence and a number of caries-related factors in 15-18-yr-olds, in order to estimate the explanatory value of consumption of sweets under different conditions. Sixty-nine 18-yr-olds were interviewed about consumption of sweets and other sugar-containing products during the past 3 yr. Data on oral hygiene, salivary counts of mutans streptococci and lactobacilli, salivary flow rate and oral sugar clearance time were collected when the individuals were 15 and 18 yr old. Caries incidence for the 3-yr period was expressed as a percentage of the number of caries-free approximal surfaces of premolars and molars at the age of 15. Simple linear correlations between caries incidence and the different variables showed that lactobacilli count ranked first (r = 0.26), sweets second (r = 0.25), and mutans streptococci count third (r = 0.24). The r value for caries incidence and consumption of sweets increased in subgroups with combinations of poor oral hygiene, a high intake of other sugary products and a low salivary flow rate (r = 0.67-0.70). In conclusion, consumption of sweets should still be considered an important caries-related factor and particularly harmful when oral hygiene is poor and consumption of other sugary products is high. 相似文献
566.
Inactivation of mouse alpha-globin gene by homologous recombination: mouse model of hemoglobin H disease 总被引:1,自引:0,他引:1
We have disrupted the 5' locus of the duplicated adult alpha-globin genes by gene targeting in the mouse embryonic stem cells and created mice with alpha-thalassemia syndromes. The heterozygous knockout mice (.alpha/alpha alpha) are asymptomatic like the silent carriers in humans whereas the homozygous knockout mice (.alpha/.alpha) show hemolytic anemia. Mice with three dysfunctional alpha-globin genes generated by breeding the 5' alpha-globin knockouts (.alpha/alpha alpha) and the deletion type alpha-thalassemia mice (../alpha alpha) produce severe hemoglobin H disease and they die in utero. These results indicate that the 5' alpha-globin gene is the predominant locus in mice, and suggest that it is even more dominant than its human homologue. 相似文献
567.
MR imaging of the knee. Part II. Chronic disorders 总被引:1,自引:0,他引:1
Hartzman S; Reicher MA; Bassett LW; Duckwiler GR; Mandelbaum B; Gold RH 《Radiology》1987,162(2):553-557
Sixty patients with symptoms of chronic disease of the knee joint were evaluated with high-resolution, thin-section magnetic resonance (MR) imaging. MR imaging depicted a wide variety of knee joint abnormalities including osteochondritis dissecans, medullary infarcts, epiphyseal osteonecrosis, intraarticular osteochondral fragments, synovial cysts, joint effusions, intraarticular soft-tissue tumors, synovial disease, leukemic infiltration of bone marrow, Osgood-Schlatter disease, and nonossifying fibroma. In two cases MR imaging depicted bone infarcts not seen on both radionuclide bone scans and standard radiographs. The highly detailed depiction of the articular cartilage was of particular importance in predicting arthroscopic findings in cases of osteochondritis dissecans. In two cases, a soft-tissue mass (pigmented villonodular synovitis) and a large osteochondral fragment undetected at arthroscopy were accurately localized with MR imaging. The results indicate that MR imaging is capable of providing information that might otherwise require multiple, sometimes invasive diagnostic procedures. 相似文献
568.
The aim of this investigation was to study the intraoral pH response on tooth surfaces in relation to dental erosion during and after drinking a sugar-free cola-type soft drink. Six different methods of drinking were tested in a randomized order: holding; short-sipping; long-sipping; gulping; nipping; and sucking. Two methods of pH measurement were used in two series of individuals. In the first series, pH was measured by using the microtouch method in 12 healthy adults at three dental erosion-prone sites: 11 palatally; 11 buccally; and at the mesiobuccal cusp tip of 16. In the second series, pH was measured by using the telemetric method in 6 healthy individuals, producing continuous recordings of pH by means of a glass electrode in a specified approximal area. The two series showed similar results, although the telemetric method generally recorded larger pH falls. Holding the drink in the mouth before swallowing led to the most pronounced pH drop, followed by the long-sipping method. Gulping resulted in only a small decrease of pH. No differences among the three intraoral sites were found when analyzed by using the microtouch method. The conclusion from this study is that the drinking method strongly affects tooth-surface pH and thereby the risk for dental erosion. It therefore seems appropriate to include advice on the method of drinking in dietary counseling related to dental erosion. 相似文献
569.
570.